[PATCH v3 0/2] iio:gyro:bmg160 Gyro Sensor driver

[PATCH v3 0/2] iio:gyro:bmg160 Gyro Sensor driver

[Srinivas Pandruvada]

v3
- Suport Only Runtime PM no fallback method. Driver will still work but
chip will be in power on mode.
- Add comment for enable disable trigger/event sequence, how they work
in reverse order using runtime pm calls

v2:
- Add device id in any-motion trigger
- Removed string comparison for trigger name to identify trigger source
- Prevent disabling any motion interrupts when both any motion trigger
and events are on, but any one of them is disabled via sysfs
- Switch on chan->type
- Created new function to raw read axis
- Explanation why need to power on for changing sampling freq and scale

v1:
- Runtime PM: Removed module parameter for delay configuration
Use RTPM autosuspend delay feature. This allows sysfs configuration of
autosuspend time.

- Trigger
As suggested, there are two triggers:
- data_ready : Trigger which will allow all gyro periodic sampled data to
be received by user space
- any-motion: When used, will configure the chipset so that data is
pushed only when there is any motion, allowing system to enter deeper idle
power states

- Events
ROC type events will send direction instead of either.
Also both events and data triggers can be enabled together.

- Addition of unbuffered TEMP read interface

- Misc error message corrections as suggested by Peter Meerwald

TBD: Add sysfs attribute to trigger to configure thresholds.
Currently the triggers don't have feature to add sysfs attributes
unlike IIO device. But this has to be a RFC patch on top. 

v0:
Base version for review

Srinivas Pandruvada (2):
  iio:gyro:bmg160 Gyro Sensor driver
  iio:gyro:bmg160 documentation

 .../ABI/testing/sysfs-bus-iio-gyro-bmg160          |    7 +
 drivers/iio/gyro/Kconfig                           |   11 +
 drivers/iio/gyro/Makefile                          |    1 +
 drivers/iio/gyro/bmg160.c                          | 1211 ++++++++++++++++++++
 4 files changed, 1230 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-gyro-bmg160
 create mode 100644 drivers/iio/gyro/bmg160.c

-- 
1.7.11.7

[PATCH v3 1/2] iio:gyro:bmg160 Gyro Sensor driver

[Srinivas Pandruvada]

This change implements support for BMG160 Gyro sensor. Although chip
has several advanced features, this change implements minimum set
required for using gyro sensor.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/iio/gyro/Kconfig  |   11 +
 drivers/iio/gyro/Makefile |    1 +
 drivers/iio/gyro/bmg160.c | 1211 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 1223 insertions(+)
 create mode 100644 drivers/iio/gyro/bmg160.c

diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
index ac2d69e..d630ae9 100644
--- a/drivers/iio/gyro/Kconfig
+++ b/drivers/iio/gyro/Kconfig
@@ -50,6 +50,17 @@ config ADXRS450
 	  This driver can also be built as a module.  If so, the module
 	  will be called adxrs450.
 
+config BMG160
+	tristate "BOSCH BMG160 Gyro Sensor"
+	depends on I2C
+	select IIO_TRIGGERED_BUFFER if IIO_BUFFER
+	help
+	  Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
+	  driver.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called bmg160.
+
 config HID_SENSOR_GYRO_3D
 	depends on HID_SENSOR_HUB
 	select IIO_BUFFER
diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
index 2f2752a..36a3877 100644
--- a/drivers/iio/gyro/Makefile
+++ b/drivers/iio/gyro/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_ADIS16130) += adis16130.o
 obj-$(CONFIG_ADIS16136) += adis16136.o
 obj-$(CONFIG_ADIS16260) += adis16260.o
 obj-$(CONFIG_ADXRS450) += adxrs450.o
+obj-$(CONFIG_BMG160) += bmg160.o
 
 obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
 
diff --git a/drivers/iio/gyro/bmg160.c b/drivers/iio/gyro/bmg160.c
new file mode 100644
index 0000000..80f92a6
--- /dev/null
+++ b/drivers/iio/gyro/bmg160.c
@@ -0,0 +1,1211 @@
+/*
+ * BMG160 Gyro Sensor driver
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/gpio/consumer.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/events.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define BMG160_DRV_NAME		"bmg160"
+#define BMG160_IRQ_NAME		"bmg160_event"
+#define BMG160_GPIO_NAME		"gpio_int"
+
+#define BMG160_REG_CHIP_ID		0x00
+#define BMG160_CHIP_ID_VAL		0x0F
+
+#define BMG160_REG_PMU_LPW		0x11
+#define BMG160_MODE_NORMAL		0x00
+#define BMG160_MODE_DEEP_SUSPEND	0x20
+#define BMG160_MODE_SUSPEND		0x80
+
+#define BMG160_REG_RANGE		0x0F
+
+#define BMG160_RANGE_2000DPS		0
+#define BMG160_RANGE_1000DPS		1
+#define BMG160_RANGE_500DPS		2
+#define BMG160_RANGE_250DPS		3
+#define BMG160_RANGE_125DPS		4
+
+#define BMG160_REG_PMU_BW		0x10
+#define BMG160_NO_FILTER		0
+#define BMG160_DEF_BW			100
+
+#define BMG160_REG_INT_MAP_0		0x17
+#define BMG160_INT_MAP_0_BIT_ANY	BIT(1)
+
+#define BMG160_REG_INT_MAP_1		0x18
+#define BMG160_INT_MAP_1_BIT_NEW_DATA	BIT(0)
+
+#define BMG160_REG_INT_RST_LATCH	0x21
+#define BMG160_INT_MODE_LATCH_RESET	0x80
+#define BMG160_INT_MODE_LATCH_INT	0x0F
+#define BMG160_INT_MODE_NON_LATCH_INT	0x00
+
+#define BMG160_REG_INT_EN_0		0x15
+#define BMG160_DATA_ENABLE_INT		BIT(7)
+
+#define BMG160_REG_XOUT_L		0x02
+#define BMG160_AXIS_TO_REG(axis)	(BMG160_REG_XOUT_L + (axis * 2))
+
+#define BMG160_REG_SLOPE_THRES		0x1B
+#define BMG160_SLOPE_THRES_MASK	0x0F
+
+#define BMG160_REG_MOTION_INTR		0x1C
+#define BMG160_INT_MOTION_X		BIT(0)
+#define BMG160_INT_MOTION_Y		BIT(1)
+#define BMG160_INT_MOTION_Z		BIT(2)
+#define BMG160_ANY_DUR_MASK		0x30
+#define BMG160_ANY_DUR_SHIFT		4
+
+#define BMG160_REG_INT_STATUS_2	0x0B
+#define BMG160_ANY_MOTION_MASK		0x07
+
+#define BMG160_REG_TEMP		0x08
+#define BMG160_TEMP_CENTER_VAL		23
+
+#define BMG160_MAX_STARTUP_TIME_MS	80
+
+#define BMG160_AUTO_SUSPEND_DELAY_MS	2000
+
+struct bmg160_data {
+	struct i2c_client *client;
+	struct iio_trigger *dready_trig;
+	struct iio_trigger *motion_trig;
+	struct mutex mutex;
+	s16 buffer[8];
+	u8 bw_bits;
+	u32 dps_range;
+	int ev_enable_state;
+	int slope_thres;
+	bool dready_trigger_on;
+	bool motion_trigger_on;
+	int64_t timestamp;
+};
+
+enum bmg160_axis {
+	AXIS_X,
+	AXIS_Y,
+	AXIS_Z,
+};
+
+static const struct {
+	int val;
+	int bw_bits;
+} bmg160_samp_freq_table[] = { {100, 0x07},
+			       {200, 0x06},
+			       {400, 0x03},
+			       {1000, 0x02},
+			       {2000, 0x01} };
+
+static const struct {
+	int scale;
+	int dps_range;
+} bmg160_scale_table[] = { { 1065, BMG160_RANGE_2000DPS},
+			   { 532, BMG160_RANGE_1000DPS},
+			   { 266, BMG160_RANGE_500DPS},
+			   { 133, BMG160_RANGE_250DPS},
+			   { 66, BMG160_RANGE_125DPS} };
+
+static int bmg160_set_mode(struct bmg160_data *data, u8 mode)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_PMU_LPW, mode);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_pmu_lpw\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_convert_freq_to_bit(int val)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
+		if (bmg160_samp_freq_table[i].val == val)
+			return bmg160_samp_freq_table[i].bw_bits;
+	}
+
+	return -EINVAL;
+}
+
+static int bmg160_set_bw(struct bmg160_data *data, int val)
+{
+	int ret;
+	int bw_bits;
+
+	bw_bits = bmg160_convert_freq_to_bit(val);
+	if (bw_bits < 0)
+		return bw_bits;
+
+	ret = i2c_smbus_write_byte_data(data->client, BMG160_REG_PMU_BW,
+					bw_bits);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_pmu_bw\n");
+		return ret;
+	}
+
+	data->bw_bits = bw_bits;
+
+	return 0;
+}
+
+static int bmg160_chip_init(struct bmg160_data *data)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_CHIP_ID);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_chip_id\n");
+		return ret;
+	}
+
+	dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
+	if (ret != BMG160_CHIP_ID_VAL) {
+		dev_err(&data->client->dev, "invalid chip %x\n", ret);
+		return -ENODEV;
+	}
+
+	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
+	if (ret < 0)
+		return ret;
+
+	/* Wait upto 500 ms to be ready after changing mode */
+	usleep_range(500, 1000);
+
+	/* Set Bandwidth */
+	ret = bmg160_set_bw(data, BMG160_DEF_BW);
+	if (ret < 0)
+		return ret;
+
+	/* Set Default Range */
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_RANGE,
+					BMG160_RANGE_500DPS);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_range\n");
+		return ret;
+	}
+	data->dps_range = BMG160_RANGE_500DPS;
+
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_SLOPE_THRES);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_slope_thres\n");
+		return ret;
+	}
+	data->slope_thres = ret;
+
+	/* Set default interrupt mode */
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_INT_RST_LATCH,
+					BMG160_INT_MODE_LATCH_INT |
+					BMG160_INT_MODE_LATCH_RESET);
+	if (ret < 0) {
+		dev_err(&data->client->dev,
+			"Error writing reg_motion_intr\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_set_power_state(struct bmg160_data *data, bool on)
+{
+	int ret;
+
+	if (on)
+		ret = pm_runtime_get_sync(&data->client->dev);
+	else {
+		pm_runtime_mark_last_busy(&data->client->dev);
+		ret = pm_runtime_put_autosuspend(&data->client->dev);
+	}
+
+	if (ret < 0) {
+		dev_err(&data->client->dev,
+			"Failed: bmg160_set_power_state for %d\n", on);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_setup_any_motion_interrupt(struct bmg160_data *data,
+					     bool status)
+{
+	int ret;
+
+	/* Enable/Disable INT_MAP0 mapping */
+	ret = i2c_smbus_read_byte_data(data->client,  BMG160_REG_INT_MAP_0);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_int_map0\n");
+		return ret;
+	}
+	if (status)
+		ret |= BMG160_INT_MAP_0_BIT_ANY;
+	else
+		ret &= ~BMG160_INT_MAP_0_BIT_ANY;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_INT_MAP_0,
+					ret);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_int_map0\n");
+		return ret;
+	}
+
+	/* Enable/Disable slope interrupts */
+	if (status) {
+		/* Update slope thres */
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_SLOPE_THRES,
+						data->slope_thres);
+		if (ret < 0) {
+			dev_err(&data->client->dev,
+				"Error writing reg_slope_thres\n");
+			return ret;
+		}
+
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_MOTION_INTR,
+						BMG160_INT_MOTION_X |
+						BMG160_INT_MOTION_Y |
+						BMG160_INT_MOTION_Z);
+		if (ret < 0) {
+			dev_err(&data->client->dev,
+				"Error writing reg_motion_intr\n");
+			return ret;
+		}
+
+		/*
+		 * New data interrupt is always non-latched,
+		 * which will have higher priority, so no need
+		 * to set latched mode, we will be flooded anyway with INTR
+		 */
+		if (!data->dready_trigger_on) {
+			ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_RST_LATCH,
+						BMG160_INT_MODE_LATCH_INT |
+						BMG160_INT_MODE_LATCH_RESET);
+			if (ret < 0) {
+				dev_err(&data->client->dev,
+					"Error writing reg_rst_latch\n");
+				return ret;
+			}
+		}
+
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_EN_0,
+						BMG160_DATA_ENABLE_INT);
+
+	} else
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_EN_0,
+						0);
+
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_setup_new_data_interrupt(struct bmg160_data *data,
+					   bool status)
+{
+	int ret;
+
+	/* Enable/Disable INT_MAP1 mapping */
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_MAP_1);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_int_map1\n");
+		return ret;
+	}
+
+	if (status)
+		ret |= BMG160_INT_MAP_1_BIT_NEW_DATA;
+	else
+		ret &= ~BMG160_INT_MAP_1_BIT_NEW_DATA;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_INT_MAP_1,
+					ret);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_int_map1\n");
+		return ret;
+	}
+
+	if (status) {
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_RST_LATCH,
+						BMG160_INT_MODE_NON_LATCH_INT |
+						BMG160_INT_MODE_LATCH_RESET);
+		if (ret < 0) {
+			dev_err(&data->client->dev,
+				"Error writing reg_rst_latch\n");
+				return ret;
+		}
+
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_EN_0,
+						BMG160_DATA_ENABLE_INT);
+
+	} else {
+		/* Restore interrupt mode */
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_RST_LATCH,
+						BMG160_INT_MODE_LATCH_INT |
+						BMG160_INT_MODE_LATCH_RESET);
+		if (ret < 0) {
+			dev_err(&data->client->dev,
+				"Error writing reg_rst_latch\n");
+				return ret;
+		}
+
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_EN_0,
+						0);
+	}
+
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_get_bw(struct bmg160_data *data, int *val)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
+		if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
+			*val = bmg160_samp_freq_table[i].val;
+			return IIO_VAL_INT;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int bmg160_set_scale(struct bmg160_data *data, int val)
+{
+	int ret, i;
+
+	for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
+		if (bmg160_scale_table[i].scale == val) {
+			ret = i2c_smbus_write_byte_data(
+					data->client,
+					BMG160_REG_RANGE,
+					bmg160_scale_table[i].dps_range);
+			if (ret < 0) {
+				dev_err(&data->client->dev,
+					"Error writing reg_range\n");
+				return ret;
+			}
+			data->dps_range = bmg160_scale_table[i].dps_range;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int bmg160_get_temp(struct bmg160_data *data, int *val)
+{
+	int ret;
+
+	mutex_lock(&data->mutex);
+	ret = bmg160_set_power_state(data, true);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_TEMP);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_temp\n");
+		bmg160_set_power_state(data, false);
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	*val = sign_extend32(ret, 7);
+	ret = bmg160_set_power_state(data, false);
+	mutex_unlock(&data->mutex);
+	if (ret < 0)
+		return ret;
+
+	return IIO_VAL_INT;
+}
+
+static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
+{
+	int ret;
+
+	mutex_lock(&data->mutex);
+	ret = bmg160_set_power_state(data, true);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	ret = i2c_smbus_read_word_data(data->client, BMG160_AXIS_TO_REG(axis));
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading axis %d\n", axis);
+		bmg160_set_power_state(data, false);
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	*val = sign_extend32(ret, 15);
+	ret = bmg160_set_power_state(data, false);
+	mutex_unlock(&data->mutex);
+	if (ret < 0)
+		return ret;
+
+	return IIO_VAL_INT;
+}
+
+static int bmg160_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->type) {
+		case IIO_TEMP:
+			return bmg160_get_temp(data, val);
+		case IIO_ANGL_VEL:
+			if (iio_buffer_enabled(indio_dev))
+				return -EBUSY;
+			else
+				return bmg160_get_axis(data, chan->scan_index,
+						       val);
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_OFFSET:
+		if (chan->type == IIO_TEMP) {
+			*val = BMG160_TEMP_CENTER_VAL;
+			return IIO_VAL_INT;
+		} else
+			return -EINVAL;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		switch (chan->type) {
+		case IIO_TEMP:
+			*val2 = 500000;
+			return IIO_VAL_INT_PLUS_MICRO;
+		case IIO_ANGL_VEL:
+		{
+			int i;
+
+			for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
+				if (bmg160_scale_table[i].dps_range ==
+							data->dps_range) {
+					*val2 = bmg160_scale_table[i].scale;
+					return IIO_VAL_INT_PLUS_MICRO;
+				}
+			}
+			return -EINVAL;
+		}
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val2 = 0;
+		mutex_lock(&data->mutex);
+		ret = bmg160_get_bw(data, val);
+		mutex_unlock(&data->mutex);
+		return ret;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int bmg160_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		mutex_lock(&data->mutex);
+		/*
+		 * Section 4.2 of spec
+		 * In suspend mode, the only supported operations are reading
+		 * registers as well as writing to the (0x14) softreset
+		 * register. Since we will be in suspend mode by default, change
+		 * mode to power on for other writes.
+		 */
+		ret = bmg160_set_power_state(data, true);
+		if (ret < 0) {
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_bw(data, val);
+		if (ret < 0) {
+			bmg160_set_power_state(data, false);
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_power_state(data, false);
+		mutex_unlock(&data->mutex);
+		return ret;
+	case IIO_CHAN_INFO_SCALE:
+		if (val)
+			return -EINVAL;
+
+		mutex_lock(&data->mutex);
+		/* Refer to comments above for the suspend mode ops */
+		ret = bmg160_set_power_state(data, true);
+		if (ret < 0) {
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_scale(data, val2);
+		if (ret < 0) {
+			bmg160_set_power_state(data, false);
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_power_state(data, false);
+		mutex_unlock(&data->mutex);
+		return ret;
+	default:
+		return -EINVAL;
+	}
+
+	return -EINVAL;
+}
+
+static int bmg160_read_event(struct iio_dev *indio_dev,
+			     const struct iio_chan_spec *chan,
+			     enum iio_event_type type,
+			     enum iio_event_direction dir,
+			     enum iio_event_info info,
+			     int *val, int *val2)
+{
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	*val2 = 0;
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		*val = data->slope_thres & BMG160_SLOPE_THRES_MASK;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return IIO_VAL_INT;
+}
+
+static int bmg160_write_event(struct iio_dev *indio_dev,
+			      const struct iio_chan_spec *chan,
+			      enum iio_event_type type,
+			      enum iio_event_direction dir,
+			      enum iio_event_info info,
+			      int val, int val2)
+{
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		if (data->ev_enable_state)
+			return -EBUSY;
+		data->slope_thres &= ~BMG160_SLOPE_THRES_MASK;
+		data->slope_thres |= (val & BMG160_SLOPE_THRES_MASK);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int bmg160_read_event_config(struct iio_dev *indio_dev,
+				    const struct iio_chan_spec *chan,
+				    enum iio_event_type type,
+				    enum iio_event_direction dir)
+{
+
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	return data->ev_enable_state;
+}
+
+static int bmg160_write_event_config(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir,
+				     int state)
+{
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (state && data->ev_enable_state)
+		return 0;
+
+	mutex_lock(&data->mutex);
+
+	if (!state && data->motion_trigger_on) {
+		data->ev_enable_state = 0;
+		mutex_unlock(&data->mutex);
+		return 0;
+	}
+	/*
+	 * We will expect the enable and disable to do operation in
+	 * in reverse order. This will happen here anyway as our
+	 * resume operation uses sync mode runtime pm calls, the
+	 * suspend operation will be delayed by autosuspend delay
+	 * So the disable operation will still happen in reverse of
+	 * enable operation. When runtime pm is disabled the mode
+	 * is always on so sequence doesn't matter
+	 */
+	ret = bmg160_set_power_state(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	ret =  bmg160_setup_any_motion_interrupt(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	data->ev_enable_state = state;
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+static int bmg160_validate_trigger(struct iio_dev *indio_dev,
+				   struct iio_trigger *trig)
+{
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	if (data->dready_trig != trig && data->motion_trig != trig)
+		return -EINVAL;
+
+	return 0;
+}
+
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 400 1000 2000");
+
+static IIO_CONST_ATTR(in_anglvel_scale_available,
+		      "0.001065 0.000532 0.000266 0.000133 0.000066");
+
+static struct attribute *bmg160_attributes[] = {
+	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
+	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group bmg160_attrs_group = {
+	.attrs = bmg160_attributes,
+};
+
+static const struct iio_event_spec bmg160_event = {
+		.type = IIO_EV_TYPE_ROC,
+		.dir = IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING,
+		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
+				       BIT(IIO_EV_INFO_ENABLE)
+};
+
+#define BMG160_CHANNEL(_axis) {					\
+	.type = IIO_ANGL_VEL,						\
+	.modified = 1,							\
+	.channel2 = IIO_MOD_##_axis,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
+				    BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
+	.scan_index = AXIS_##_axis,					\
+	.scan_type = {							\
+		.sign = 's',						\
+		.realbits = 16,					\
+		.storagebits = 16,					\
+	},								\
+	.event_spec = &bmg160_event,					\
+	.num_event_specs = 1						\
+}
+
+static const struct iio_chan_spec bmg160_channels[] = {
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE) |
+				      BIT(IIO_CHAN_INFO_OFFSET),
+		.scan_index = -1,
+	},
+	BMG160_CHANNEL(X),
+	BMG160_CHANNEL(Y),
+	BMG160_CHANNEL(Z),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+static const struct iio_info bmg160_info = {
+	.attrs			= &bmg160_attrs_group,
+	.read_raw		= bmg160_read_raw,
+	.write_raw		= bmg160_write_raw,
+	.read_event_value	= bmg160_read_event,
+	.write_event_value	= bmg160_write_event,
+	.write_event_config	= bmg160_write_event_config,
+	.read_event_config	= bmg160_read_event_config,
+	.validate_trigger	= bmg160_validate_trigger,
+	.driver_module		= THIS_MODULE,
+};
+
+static irqreturn_t bmg160_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int bit, ret, i = 0;
+
+	mutex_lock(&data->mutex);
+	for_each_set_bit(bit, indio_dev->buffer->scan_mask,
+			 indio_dev->masklength) {
+		ret = i2c_smbus_read_word_data(data->client,
+					       BMG160_AXIS_TO_REG(bit));
+		if (ret < 0) {
+			mutex_unlock(&data->mutex);
+			goto err;
+		}
+		data->buffer[i++] = ret;
+	}
+	mutex_unlock(&data->mutex);
+
+	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+					   data->timestamp);
+err:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int bmg160_trig_try_reen(struct iio_trigger *trig)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int ret;
+
+	/* new data interrupts don't need ack */
+	if (data->dready_trigger_on)
+		return 0;
+
+	/* Set latched mode interrupt and clear any latched interrupt */
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_INT_RST_LATCH,
+					BMG160_INT_MODE_LATCH_INT |
+					BMG160_INT_MODE_LATCH_RESET);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_data_rdy_trigger_set_state(struct iio_trigger *trig,
+					     bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->mutex);
+
+	if (!state && data->ev_enable_state && data->motion_trigger_on) {
+		data->motion_trigger_on = false;
+		mutex_unlock(&data->mutex);
+		return 0;
+	}
+
+	/*
+	 * Refer to comment in bmg160_write_event_config for
+	 * enable/disable operation order
+	 */
+	ret = bmg160_set_power_state(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+	if (data->motion_trig == trig)
+		ret =  bmg160_setup_any_motion_interrupt(data, state);
+	else
+		ret = bmg160_setup_new_data_interrupt(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+	if (data->motion_trig == trig)
+		data->motion_trigger_on = state;
+	else
+		data->dready_trigger_on = state;
+
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+static const struct iio_trigger_ops bmg160_trigger_ops = {
+	.set_trigger_state = bmg160_data_rdy_trigger_set_state,
+	.try_reenable = bmg160_trig_try_reen,
+	.owner = THIS_MODULE,
+};
+
+static irqreturn_t bmg160_event_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int ret;
+	int dir;
+
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_STATUS_2);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_int_status2\n");
+		goto ack_intr_status;
+	}
+
+	if (ret & 0x08)
+		dir = IIO_EV_DIR_RISING;
+	else
+		dir = IIO_EV_DIR_FALLING;
+
+	if (ret & BMG160_ANY_MOTION_MASK)
+		iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
+							0,
+							IIO_MOD_X_OR_Y_OR_Z,
+							IIO_EV_TYPE_ROC,
+							dir),
+							data->timestamp);
+
+ack_intr_status:
+	if (!data->dready_trigger_on) {
+		ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_INT_RST_LATCH,
+					BMG160_INT_MODE_LATCH_INT |
+					BMG160_INT_MODE_LATCH_RESET);
+		if (ret < 0)
+			dev_err(&data->client->dev,
+				"Error writing reg_rst_latch\n");
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t bmg160_data_rdy_trig_poll(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	data->timestamp = iio_get_time_ns();
+
+	if (data->dready_trigger_on)
+		iio_trigger_poll(data->dready_trig);
+	else if (data->motion_trigger_on)
+		iio_trigger_poll(data->motion_trig);
+
+	if (data->ev_enable_state)
+		return IRQ_WAKE_THREAD;
+	else
+		return IRQ_HANDLED;
+
+}
+
+static int bmg160_acpi_gpio_probe(struct i2c_client *client,
+				  struct bmg160_data *data)
+{
+	const struct acpi_device_id *id;
+	struct device *dev;
+	struct gpio_desc *gpio;
+	int ret;
+
+	if (!client)
+		return -EINVAL;
+
+	dev = &client->dev;
+	if (!ACPI_HANDLE(dev))
+		return -ENODEV;
+
+	id = acpi_match_device(dev->driver->acpi_match_table, dev);
+	if (!id)
+		return -ENODEV;
+
+	/* data ready gpio interrupt pin */
+	gpio = devm_gpiod_get_index(dev, BMG160_GPIO_NAME, 0);
+	if (IS_ERR(gpio)) {
+		dev_err(dev, "acpi gpio get index failed\n");
+		return PTR_ERR(gpio);
+	}
+
+	ret = gpiod_direction_input(gpio);
+	if (ret)
+		return ret;
+
+	ret = gpiod_to_irq(gpio);
+
+	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
+
+	return ret;
+}
+
+static int bmg160_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct bmg160_data *data;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->client = client;
+
+	ret = bmg160_chip_init(data);
+	if (ret < 0)
+		return ret;
+
+	mutex_init(&data->mutex);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->channels = bmg160_channels;
+	indio_dev->num_channels = ARRAY_SIZE(bmg160_channels);
+	indio_dev->name = BMG160_DRV_NAME;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &bmg160_info;
+
+	if (client->irq <= 0)
+		client->irq = bmg160_acpi_gpio_probe(client, data);
+
+	if (client->irq > 0) {
+		ret = devm_request_threaded_irq(&client->dev,
+						client->irq,
+						bmg160_data_rdy_trig_poll,
+						bmg160_event_handler,
+						IRQF_TRIGGER_RISING,
+						BMG160_IRQ_NAME,
+						indio_dev);
+		if (ret)
+			return ret;
+
+		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
+							   "%s-dev%d",
+							   indio_dev->name,
+							   indio_dev->id);
+		if (!data->dready_trig)
+			return -ENOMEM;
+
+		data->motion_trig = devm_iio_trigger_alloc(&client->dev,
+							  "%s-any-motion-dev%d",
+							  indio_dev->name,
+							  indio_dev->id);
+		if (!data->motion_trig)
+			return -ENOMEM;
+
+		data->dready_trig->dev.parent = &client->dev;
+		data->dready_trig->ops = &bmg160_trigger_ops;
+		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
+		ret = iio_trigger_register(data->dready_trig);
+		if (ret)
+			return ret;
+
+		data->motion_trig->dev.parent = &client->dev;
+		data->motion_trig->ops = &bmg160_trigger_ops;
+		iio_trigger_set_drvdata(data->motion_trig, indio_dev);
+		ret = iio_trigger_register(data->motion_trig);
+		if (ret) {
+			data->motion_trig = NULL;
+			goto err_trigger_unregister;
+		}
+
+		ret = iio_triggered_buffer_setup(indio_dev,
+						 NULL,
+						 bmg160_trigger_handler,
+						 NULL);
+		if (ret < 0) {
+			dev_err(&client->dev,
+				"iio triggered buffer setup failed\n");
+			goto err_trigger_unregister;
+		}
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&client->dev, "unable to register iio device\n");
+		goto err_buffer_cleanup;
+	}
+
+	ret = pm_runtime_set_active(&client->dev);
+	if (ret)
+		goto err_iio_unregister;
+
+	pm_runtime_enable(&client->dev);
+	pm_runtime_set_autosuspend_delay(&client->dev,
+					 BMG160_AUTO_SUSPEND_DELAY_MS);
+	pm_runtime_use_autosuspend(&client->dev);
+
+	return 0;
+
+err_iio_unregister:
+	iio_device_unregister(indio_dev);
+err_buffer_cleanup:
+	if (data->dready_trig)
+		iio_triggered_buffer_cleanup(indio_dev);
+err_trigger_unregister:
+	if (data->dready_trig)
+		iio_trigger_unregister(data->dready_trig);
+	if (data->motion_trig)
+		iio_trigger_unregister(data->motion_trig);
+
+	return ret;
+}
+
+static int bmg160_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	pm_runtime_disable(&client->dev);
+	pm_runtime_set_suspended(&client->dev);
+	pm_runtime_put_noidle(&client->dev);
+
+	iio_device_unregister(indio_dev);
+
+	if (data->dready_trig) {
+		iio_triggered_buffer_cleanup(indio_dev);
+		iio_trigger_unregister(data->dready_trig);
+		iio_trigger_unregister(data->motion_trig);
+	}
+
+	mutex_lock(&data->mutex);
+	bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int bmg160_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	mutex_lock(&data->mutex);
+	bmg160_set_mode(data, BMG160_MODE_SUSPEND);
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+static int bmg160_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	mutex_lock(&data->mutex);
+	if (data->dready_trigger_on || data->motion_trigger_on ||
+							data->ev_enable_state)
+		bmg160_set_mode(data, BMG160_MODE_NORMAL);
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_PM_RUNTIME
+static int bmg160_runtime_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
+}
+
+static int bmg160_runtime_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct bmg160_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
+	if (ret < 0)
+		return ret;
+
+	msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops bmg160_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(bmg160_suspend, bmg160_resume)
+	SET_RUNTIME_PM_OPS(bmg160_runtime_suspend,
+			   bmg160_runtime_resume, NULL)
+};
+
+static const struct acpi_device_id bmg160_acpi_match[] = {
+	{"BMG0160", 0},
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, bmg160_acpi_match);
+
+static const struct i2c_device_id bmg160_id[] = {
+	{"bmg160", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, bmg160_id);
+
+static struct i2c_driver bmg160_driver = {
+	.driver = {
+		.name	= BMG160_DRV_NAME,
+		.acpi_match_table = ACPI_PTR(bmg160_acpi_match),
+		.pm	= &bmg160_pm_ops,
+	},
+	.probe		= bmg160_probe,
+	.remove		= bmg160_remove,
+	.id_table	= bmg160_id,
+};
+module_i2c_driver(bmg160_driver);
+
+MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("BMG160 Gyro driver");
-- 
1.7.11.7

[PATCH v3 2/2] iio:gyro:bmg160 documentation

[Srinivas Pandruvada]

Added any-motion trigger documentation.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 Documentation/ABI/testing/sysfs-bus-iio-gyro-bmg160 | 7 +++++++
 1 file changed, 7 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-gyro-bmg160

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-gyro-bmg160 b/Documentation/ABI/testing/sysfs-bus-iio-gyro-bmg160
new file mode 100644
index 0000000..e98209c
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-gyro-bmg160
@@ -0,0 +1,7 @@
+What:		/sys/bus/iio/devices/triggerX/name = "bmg160-any-motion-devX"
+KernelVersion:	3.17
+Contact:	linux-iio@vger.kernel.org
+Description:
+		The BMG160 gyro kernel module provides an additional trigger,
+		which sets driver in a mode, where data is pushed to the buffer
+		only when there is any motion.
-- 
1.7.11.7

Re: [PATCH v3 1/2] iio:gyro:bmg160 Gyro Sensor driver

[Jonathan Cameron]

On 05/08/14 22:57, Srinivas Pandruvada wrote:
> This change implements support for BMG160 Gyro sensor. Although chip
> has several advanced features, this change implements minimum set
> required for using gyro sensor.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
One more query.  In the write_raw function you always enable then suspend the
device.  The enable is safe, but if you have a write to the attributes
whilst operating in triggered / buffered mode will it not disable the
device?  It is perfectly permissible to ignore such a write (return -EBUSY)
but I don't think you are doing so.

Otherwise, looks good to me.  Nice explanatory comments as well!
> ---
>  drivers/iio/gyro/Kconfig  |   11 +
>  drivers/iio/gyro/Makefile |    1 +
>  drivers/iio/gyro/bmg160.c | 1211 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 1223 insertions(+)
>  create mode 100644 drivers/iio/gyro/bmg160.c
>
> diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
> index ac2d69e..d630ae9 100644
> --- a/drivers/iio/gyro/Kconfig
> +++ b/drivers/iio/gyro/Kconfig
> @@ -50,6 +50,17 @@ config ADXRS450
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called adxrs450.
>
> +config BMG160
> +	tristate "BOSCH BMG160 Gyro Sensor"
> +	depends on I2C
> +	select IIO_TRIGGERED_BUFFER if IIO_BUFFER
> +	help
> +	  Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
> +	  driver.
> +
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called bmg160.
> +
>  config HID_SENSOR_GYRO_3D
>  	depends on HID_SENSOR_HUB
>  	select IIO_BUFFER
> diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
> index 2f2752a..36a3877 100644
> --- a/drivers/iio/gyro/Makefile
> +++ b/drivers/iio/gyro/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_ADIS16130) += adis16130.o
>  obj-$(CONFIG_ADIS16136) += adis16136.o
>  obj-$(CONFIG_ADIS16260) += adis16260.o
>  obj-$(CONFIG_ADXRS450) += adxrs450.o
> +obj-$(CONFIG_BMG160) += bmg160.o
>
>  obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
>
> diff --git a/drivers/iio/gyro/bmg160.c b/drivers/iio/gyro/bmg160.c
> new file mode 100644
> index 0000000..80f92a6
> --- /dev/null
> +++ b/drivers/iio/gyro/bmg160.c
> @@ -0,0 +1,1211 @@
> +/*
> + * BMG160 Gyro Sensor driver
> + * Copyright (c) 2014, Intel Corporation.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> + * more details.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/delay.h>
> +#include <linux/slab.h>
> +#include <linux/acpi.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/pm.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/events.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> +#define BMG160_DRV_NAME		"bmg160"
> +#define BMG160_IRQ_NAME		"bmg160_event"
> +#define BMG160_GPIO_NAME		"gpio_int"
> +
> +#define BMG160_REG_CHIP_ID		0x00
> +#define BMG160_CHIP_ID_VAL		0x0F
> +
> +#define BMG160_REG_PMU_LPW		0x11
> +#define BMG160_MODE_NORMAL		0x00
> +#define BMG160_MODE_DEEP_SUSPEND	0x20
> +#define BMG160_MODE_SUSPEND		0x80
> +
> +#define BMG160_REG_RANGE		0x0F
> +
> +#define BMG160_RANGE_2000DPS		0
> +#define BMG160_RANGE_1000DPS		1
> +#define BMG160_RANGE_500DPS		2
> +#define BMG160_RANGE_250DPS		3
> +#define BMG160_RANGE_125DPS		4
> +
> +#define BMG160_REG_PMU_BW		0x10
> +#define BMG160_NO_FILTER		0
> +#define BMG160_DEF_BW			100
> +
> +#define BMG160_REG_INT_MAP_0		0x17
> +#define BMG160_INT_MAP_0_BIT_ANY	BIT(1)
> +
> +#define BMG160_REG_INT_MAP_1		0x18
> +#define BMG160_INT_MAP_1_BIT_NEW_DATA	BIT(0)
> +
> +#define BMG160_REG_INT_RST_LATCH	0x21
> +#define BMG160_INT_MODE_LATCH_RESET	0x80
> +#define BMG160_INT_MODE_LATCH_INT	0x0F
> +#define BMG160_INT_MODE_NON_LATCH_INT	0x00
> +
> +#define BMG160_REG_INT_EN_0		0x15
> +#define BMG160_DATA_ENABLE_INT		BIT(7)
> +
> +#define BMG160_REG_XOUT_L		0x02
> +#define BMG160_AXIS_TO_REG(axis)	(BMG160_REG_XOUT_L + (axis * 2))
> +
> +#define BMG160_REG_SLOPE_THRES		0x1B
> +#define BMG160_SLOPE_THRES_MASK	0x0F
> +
> +#define BMG160_REG_MOTION_INTR		0x1C
> +#define BMG160_INT_MOTION_X		BIT(0)
> +#define BMG160_INT_MOTION_Y		BIT(1)
> +#define BMG160_INT_MOTION_Z		BIT(2)
> +#define BMG160_ANY_DUR_MASK		0x30
> +#define BMG160_ANY_DUR_SHIFT		4
> +
> +#define BMG160_REG_INT_STATUS_2	0x0B
> +#define BMG160_ANY_MOTION_MASK		0x07
> +
> +#define BMG160_REG_TEMP		0x08
> +#define BMG160_TEMP_CENTER_VAL		23
> +
> +#define BMG160_MAX_STARTUP_TIME_MS	80
> +
> +#define BMG160_AUTO_SUSPEND_DELAY_MS	2000
> +
> +struct bmg160_data {
> +	struct i2c_client *client;
> +	struct iio_trigger *dready_trig;
> +	struct iio_trigger *motion_trig;
> +	struct mutex mutex;
> +	s16 buffer[8];
> +	u8 bw_bits;
> +	u32 dps_range;
> +	int ev_enable_state;
> +	int slope_thres;
> +	bool dready_trigger_on;
> +	bool motion_trigger_on;
> +	int64_t timestamp;
> +};
> +
> +enum bmg160_axis {
> +	AXIS_X,
> +	AXIS_Y,
> +	AXIS_Z,
> +};
> +
> +static const struct {
> +	int val;
> +	int bw_bits;
> +} bmg160_samp_freq_table[] = { {100, 0x07},
> +			       {200, 0x06},
> +			       {400, 0x03},
> +			       {1000, 0x02},
> +			       {2000, 0x01} };
> +
> +static const struct {
> +	int scale;
> +	int dps_range;
> +} bmg160_scale_table[] = { { 1065, BMG160_RANGE_2000DPS},
> +			   { 532, BMG160_RANGE_1000DPS},
> +			   { 266, BMG160_RANGE_500DPS},
> +			   { 133, BMG160_RANGE_250DPS},
> +			   { 66, BMG160_RANGE_125DPS} };
> +
> +static int bmg160_set_mode(struct bmg160_data *data, u8 mode)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					BMG160_REG_PMU_LPW, mode);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_pmu_lpw\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmg160_convert_freq_to_bit(int val)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
> +		if (bmg160_samp_freq_table[i].val == val)
> +			return bmg160_samp_freq_table[i].bw_bits;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int bmg160_set_bw(struct bmg160_data *data, int val)
> +{
> +	int ret;
> +	int bw_bits;
> +
> +	bw_bits = bmg160_convert_freq_to_bit(val);
> +	if (bw_bits < 0)
> +		return bw_bits;
> +
> +	ret = i2c_smbus_write_byte_data(data->client, BMG160_REG_PMU_BW,
> +					bw_bits);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_pmu_bw\n");
> +		return ret;
> +	}
> +
> +	data->bw_bits = bw_bits;
> +
> +	return 0;
> +}
> +
> +static int bmg160_chip_init(struct bmg160_data *data)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_CHIP_ID);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_chip_id\n");
> +		return ret;
> +	}
> +
> +	dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
> +	if (ret != BMG160_CHIP_ID_VAL) {
> +		dev_err(&data->client->dev, "invalid chip %x\n", ret);
> +		return -ENODEV;
> +	}
> +
> +	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Wait upto 500 ms to be ready after changing mode */
> +	usleep_range(500, 1000);
> +
> +	/* Set Bandwidth */
> +	ret = bmg160_set_bw(data, BMG160_DEF_BW);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Set Default Range */
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					BMG160_REG_RANGE,
> +					BMG160_RANGE_500DPS);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_range\n");
> +		return ret;
> +	}
> +	data->dps_range = BMG160_RANGE_500DPS;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_SLOPE_THRES);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_slope_thres\n");
> +		return ret;
> +	}
> +	data->slope_thres = ret;
> +
> +	/* Set default interrupt mode */
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					BMG160_REG_INT_RST_LATCH,
> +					BMG160_INT_MODE_LATCH_INT |
> +					BMG160_INT_MODE_LATCH_RESET);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev,
> +			"Error writing reg_motion_intr\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmg160_set_power_state(struct bmg160_data *data, bool on)
> +{
> +	int ret;
> +
> +	if (on)
> +		ret = pm_runtime_get_sync(&data->client->dev);
> +	else {
> +		pm_runtime_mark_last_busy(&data->client->dev);
> +		ret = pm_runtime_put_autosuspend(&data->client->dev);
> +	}
> +
> +	if (ret < 0) {
> +		dev_err(&data->client->dev,
> +			"Failed: bmg160_set_power_state for %d\n", on);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmg160_setup_any_motion_interrupt(struct bmg160_data *data,
> +					     bool status)
> +{
> +	int ret;
> +
> +	/* Enable/Disable INT_MAP0 mapping */
> +	ret = i2c_smbus_read_byte_data(data->client,  BMG160_REG_INT_MAP_0);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_int_map0\n");
> +		return ret;
> +	}
> +	if (status)
> +		ret |= BMG160_INT_MAP_0_BIT_ANY;
> +	else
> +		ret &= ~BMG160_INT_MAP_0_BIT_ANY;
> +
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					BMG160_REG_INT_MAP_0,
> +					ret);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_int_map0\n");
> +		return ret;
> +	}
> +
> +	/* Enable/Disable slope interrupts */
> +	if (status) {
> +		/* Update slope thres */
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_SLOPE_THRES,
> +						data->slope_thres);
> +		if (ret < 0) {
> +			dev_err(&data->client->dev,
> +				"Error writing reg_slope_thres\n");
> +			return ret;
> +		}
> +
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_MOTION_INTR,
> +						BMG160_INT_MOTION_X |
> +						BMG160_INT_MOTION_Y |
> +						BMG160_INT_MOTION_Z);
> +		if (ret < 0) {
> +			dev_err(&data->client->dev,
> +				"Error writing reg_motion_intr\n");
> +			return ret;
> +		}
> +
> +		/*
> +		 * New data interrupt is always non-latched,
> +		 * which will have higher priority, so no need
> +		 * to set latched mode, we will be flooded anyway with INTR
> +		 */
> +		if (!data->dready_trigger_on) {
> +			ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_INT_RST_LATCH,
> +						BMG160_INT_MODE_LATCH_INT |
> +						BMG160_INT_MODE_LATCH_RESET);
> +			if (ret < 0) {
> +				dev_err(&data->client->dev,
> +					"Error writing reg_rst_latch\n");
> +				return ret;
> +			}
> +		}
> +
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_INT_EN_0,
> +						BMG160_DATA_ENABLE_INT);
> +
> +	} else
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_INT_EN_0,
> +						0);
> +
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmg160_setup_new_data_interrupt(struct bmg160_data *data,
> +					   bool status)
> +{
> +	int ret;
> +
> +	/* Enable/Disable INT_MAP1 mapping */
> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_MAP_1);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_int_map1\n");
> +		return ret;
> +	}
> +
> +	if (status)
> +		ret |= BMG160_INT_MAP_1_BIT_NEW_DATA;
> +	else
> +		ret &= ~BMG160_INT_MAP_1_BIT_NEW_DATA;
> +
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					BMG160_REG_INT_MAP_1,
> +					ret);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_int_map1\n");
> +		return ret;
> +	}
> +
> +	if (status) {
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_INT_RST_LATCH,
> +						BMG160_INT_MODE_NON_LATCH_INT |
> +						BMG160_INT_MODE_LATCH_RESET);
> +		if (ret < 0) {
> +			dev_err(&data->client->dev,
> +				"Error writing reg_rst_latch\n");
> +				return ret;
> +		}
> +
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_INT_EN_0,
> +						BMG160_DATA_ENABLE_INT);
> +
> +	} else {
> +		/* Restore interrupt mode */
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_INT_RST_LATCH,
> +						BMG160_INT_MODE_LATCH_INT |
> +						BMG160_INT_MODE_LATCH_RESET);
> +		if (ret < 0) {
> +			dev_err(&data->client->dev,
> +				"Error writing reg_rst_latch\n");
> +				return ret;
> +		}
> +
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						BMG160_REG_INT_EN_0,
> +						0);
> +	}
> +
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmg160_get_bw(struct bmg160_data *data, int *val)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
> +		if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
> +			*val = bmg160_samp_freq_table[i].val;
> +			return IIO_VAL_INT;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int bmg160_set_scale(struct bmg160_data *data, int val)
> +{
> +	int ret, i;
> +
> +	for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
> +		if (bmg160_scale_table[i].scale == val) {
> +			ret = i2c_smbus_write_byte_data(
> +					data->client,
> +					BMG160_REG_RANGE,
> +					bmg160_scale_table[i].dps_range);
> +			if (ret < 0) {
> +				dev_err(&data->client->dev,
> +					"Error writing reg_range\n");
> +				return ret;
> +			}
> +			data->dps_range = bmg160_scale_table[i].dps_range;
> +			return 0;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int bmg160_get_temp(struct bmg160_data *data, int *val)
> +{
> +	int ret;
> +
> +	mutex_lock(&data->mutex);
> +	ret = bmg160_set_power_state(data, true);
> +	if (ret < 0) {
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +
> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_TEMP);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_temp\n");
> +		bmg160_set_power_state(data, false);
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +
> +	*val = sign_extend32(ret, 7);
> +	ret = bmg160_set_power_state(data, false);
> +	mutex_unlock(&data->mutex);
> +	if (ret < 0)
> +		return ret;
> +
> +	return IIO_VAL_INT;
> +}
> +
> +static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
> +{
> +	int ret;
> +
> +	mutex_lock(&data->mutex);
> +	ret = bmg160_set_power_state(data, true);
> +	if (ret < 0) {
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +
> +	ret = i2c_smbus_read_word_data(data->client, BMG160_AXIS_TO_REG(axis));
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading axis %d\n", axis);
> +		bmg160_set_power_state(data, false);
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +
> +	*val = sign_extend32(ret, 15);
> +	ret = bmg160_set_power_state(data, false);
> +	mutex_unlock(&data->mutex);
> +	if (ret < 0)
> +		return ret;
> +
> +	return IIO_VAL_INT;
> +}
> +
> +static int bmg160_read_raw(struct iio_dev *indio_dev,
> +			   struct iio_chan_spec const *chan,
> +			   int *val, int *val2, long mask)
> +{
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_TEMP:
> +			return bmg160_get_temp(data, val);
> +		case IIO_ANGL_VEL:
> +			if (iio_buffer_enabled(indio_dev))
> +				return -EBUSY;
> +			else
> +				return bmg160_get_axis(data, chan->scan_index,
> +						       val);
> +		default:
> +			return -EINVAL;
> +		}
> +	case IIO_CHAN_INFO_OFFSET:
> +		if (chan->type == IIO_TEMP) {
> +			*val = BMG160_TEMP_CENTER_VAL;
> +			return IIO_VAL_INT;
> +		} else
> +			return -EINVAL;
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = 0;
> +		switch (chan->type) {
> +		case IIO_TEMP:
> +			*val2 = 500000;
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		case IIO_ANGL_VEL:
> +		{
> +			int i;
> +
> +			for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
> +				if (bmg160_scale_table[i].dps_range ==
> +							data->dps_range) {
> +					*val2 = bmg160_scale_table[i].scale;
> +					return IIO_VAL_INT_PLUS_MICRO;
> +				}
> +			}
> +			return -EINVAL;
> +		}
> +		default:
> +			return -EINVAL;
> +		}
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		*val2 = 0;
> +		mutex_lock(&data->mutex);
> +		ret = bmg160_get_bw(data, val);
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int bmg160_write_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan,
> +			    int val, int val2, long mask)
> +{
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		mutex_lock(&data->mutex);
> +		/*
> +		 * Section 4.2 of spec
> +		 * In suspend mode, the only supported operations are reading
> +		 * registers as well as writing to the (0x14) softreset
> +		 * register. Since we will be in suspend mode by default, change
> +		 * mode to power on for other writes.
> +		 */
> +		ret = bmg160_set_power_state(data, true);
> +		if (ret < 0) {
> +			mutex_unlock(&data->mutex);
> +			return ret;
> +		}
> +		ret = bmg160_set_bw(data, val);
> +		if (ret < 0) {
> +			bmg160_set_power_state(data, false);
> +			mutex_unlock(&data->mutex);
> +			return ret;
> +		}
> +		ret = bmg160_set_power_state(data, false);
Could this end up disabling the part when in triggered mode?
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	case IIO_CHAN_INFO_SCALE:
> +		if (val)
> +			return -EINVAL;
> +
> +		mutex_lock(&data->mutex);
> +		/* Refer to comments above for the suspend mode ops */
> +		ret = bmg160_set_power_state(data, true);
> +		if (ret < 0) {
> +			mutex_unlock(&data->mutex);
> +			return ret;
> +		}
> +		ret = bmg160_set_scale(data, val2);
> +		if (ret < 0) {
> +			bmg160_set_power_state(data, false);
> +			mutex_unlock(&data->mutex);
> +			return ret;
> +		}
> +		ret = bmg160_set_power_state(data, false);
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int bmg160_read_event(struct iio_dev *indio_dev,
> +			     const struct iio_chan_spec *chan,
> +			     enum iio_event_type type,
> +			     enum iio_event_direction dir,
> +			     enum iio_event_info info,
> +			     int *val, int *val2)
> +{
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	*val2 = 0;
> +	switch (info) {
> +	case IIO_EV_INFO_VALUE:
> +		*val = data->slope_thres & BMG160_SLOPE_THRES_MASK;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return IIO_VAL_INT;
> +}
> +
> +static int bmg160_write_event(struct iio_dev *indio_dev,
> +			      const struct iio_chan_spec *chan,
> +			      enum iio_event_type type,
> +			      enum iio_event_direction dir,
> +			      enum iio_event_info info,
> +			      int val, int val2)
> +{
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	switch (info) {
> +	case IIO_EV_INFO_VALUE:
> +		if (data->ev_enable_state)
> +			return -EBUSY;
> +		data->slope_thres &= ~BMG160_SLOPE_THRES_MASK;
> +		data->slope_thres |= (val & BMG160_SLOPE_THRES_MASK);
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmg160_read_event_config(struct iio_dev *indio_dev,
> +				    const struct iio_chan_spec *chan,
> +				    enum iio_event_type type,
> +				    enum iio_event_direction dir)
> +{
> +
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	return data->ev_enable_state;
> +}
> +
> +static int bmg160_write_event_config(struct iio_dev *indio_dev,
> +				     const struct iio_chan_spec *chan,
> +				     enum iio_event_type type,
> +				     enum iio_event_direction dir,
> +				     int state)
> +{
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	if (state && data->ev_enable_state)
> +		return 0;
> +
> +	mutex_lock(&data->mutex);
> +
> +	if (!state && data->motion_trigger_on) {
> +		data->ev_enable_state = 0;
> +		mutex_unlock(&data->mutex);
> +		return 0;
> +	}
> +	/*
> +	 * We will expect the enable and disable to do operation in
> +	 * in reverse order. This will happen here anyway as our
> +	 * resume operation uses sync mode runtime pm calls, the
> +	 * suspend operation will be delayed by autosuspend delay
> +	 * So the disable operation will still happen in reverse of
> +	 * enable operation. When runtime pm is disabled the mode
> +	 * is always on so sequence doesn't matter
> +	 */
Thanks for the detailed comment!
> +	ret = bmg160_set_power_state(data, state);
> +	if (ret < 0) {
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +
> +	ret =  bmg160_setup_any_motion_interrupt(data, state);
> +	if (ret < 0) {
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +
> +	data->ev_enable_state = state;
> +	mutex_unlock(&data->mutex);
> +
> +	return 0;
> +}
> +
> +static int bmg160_validate_trigger(struct iio_dev *indio_dev,
> +				   struct iio_trigger *trig)
> +{
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	if (data->dready_trig != trig && data->motion_trig != trig)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 400 1000 2000");
> +
> +static IIO_CONST_ATTR(in_anglvel_scale_available,
> +		      "0.001065 0.000532 0.000266 0.000133 0.000066");
> +
> +static struct attribute *bmg160_attributes[] = {
> +	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
> +	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group bmg160_attrs_group = {
> +	.attrs = bmg160_attributes,
> +};
> +
> +static const struct iio_event_spec bmg160_event = {
> +		.type = IIO_EV_TYPE_ROC,
> +		.dir = IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING,
> +		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
> +				       BIT(IIO_EV_INFO_ENABLE)
> +};
> +
> +#define BMG160_CHANNEL(_axis) {					\
> +	.type = IIO_ANGL_VEL,						\
> +	.modified = 1,							\
> +	.channel2 = IIO_MOD_##_axis,					\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
> +				    BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
> +	.scan_index = AXIS_##_axis,					\
> +	.scan_type = {							\
> +		.sign = 's',						\
> +		.realbits = 16,					\
> +		.storagebits = 16,					\
> +	},								\
> +	.event_spec = &bmg160_event,					\
> +	.num_event_specs = 1						\
> +}
> +
> +static const struct iio_chan_spec bmg160_channels[] = {
> +	{
> +		.type = IIO_TEMP,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE) |
> +				      BIT(IIO_CHAN_INFO_OFFSET),
> +		.scan_index = -1,
> +	},
> +	BMG160_CHANNEL(X),
> +	BMG160_CHANNEL(Y),
> +	BMG160_CHANNEL(Z),
> +	IIO_CHAN_SOFT_TIMESTAMP(3),
> +};
> +
> +static const struct iio_info bmg160_info = {
> +	.attrs			= &bmg160_attrs_group,
> +	.read_raw		= bmg160_read_raw,
> +	.write_raw		= bmg160_write_raw,
> +	.read_event_value	= bmg160_read_event,
> +	.write_event_value	= bmg160_write_event,
> +	.write_event_config	= bmg160_write_event_config,
> +	.read_event_config	= bmg160_read_event_config,
> +	.validate_trigger	= bmg160_validate_trigger,
> +	.driver_module		= THIS_MODULE,
> +};
> +
> +static irqreturn_t bmg160_trigger_handler(int irq, void *p)
> +{
> +	struct iio_poll_func *pf = p;
> +	struct iio_dev *indio_dev = pf->indio_dev;
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int bit, ret, i = 0;
> +
> +	mutex_lock(&data->mutex);
> +	for_each_set_bit(bit, indio_dev->buffer->scan_mask,
> +			 indio_dev->masklength) {
> +		ret = i2c_smbus_read_word_data(data->client,
> +					       BMG160_AXIS_TO_REG(bit));
> +		if (ret < 0) {
> +			mutex_unlock(&data->mutex);
> +			goto err;
> +		}
> +		data->buffer[i++] = ret;
> +	}
> +	mutex_unlock(&data->mutex);
> +
> +	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
> +					   data->timestamp);
> +err:
> +	iio_trigger_notify_done(indio_dev->trig);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int bmg160_trig_try_reen(struct iio_trigger *trig)
> +{
> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	/* new data interrupts don't need ack */
> +	if (data->dready_trigger_on)
> +		return 0;
> +
> +	/* Set latched mode interrupt and clear any latched interrupt */
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					BMG160_REG_INT_RST_LATCH,
> +					BMG160_INT_MODE_LATCH_INT |
> +					BMG160_INT_MODE_LATCH_RESET);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bmg160_data_rdy_trigger_set_state(struct iio_trigger *trig,
> +					     bool state)
> +{
> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	mutex_lock(&data->mutex);
> +
> +	if (!state && data->ev_enable_state && data->motion_trigger_on) {
> +		data->motion_trigger_on = false;
> +		mutex_unlock(&data->mutex);
> +		return 0;
> +	}
> +
> +	/*
> +	 * Refer to comment in bmg160_write_event_config for
> +	 * enable/disable operation order
> +	 */
> +	ret = bmg160_set_power_state(data, state);
> +	if (ret < 0) {
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +	if (data->motion_trig == trig)
> +		ret =  bmg160_setup_any_motion_interrupt(data, state);
> +	else
> +		ret = bmg160_setup_new_data_interrupt(data, state);
> +	if (ret < 0) {
> +		mutex_unlock(&data->mutex);
> +		return ret;
> +	}
> +	if (data->motion_trig == trig)
> +		data->motion_trigger_on = state;
> +	else
> +		data->dready_trigger_on = state;
> +
> +	mutex_unlock(&data->mutex);
> +
> +	return 0;
> +}
> +
> +static const struct iio_trigger_ops bmg160_trigger_ops = {
> +	.set_trigger_state = bmg160_data_rdy_trigger_set_state,
> +	.try_reenable = bmg160_trig_try_reen,
> +	.owner = THIS_MODULE,
> +};
> +
> +static irqreturn_t bmg160_event_handler(int irq, void *private)
> +{
> +	struct iio_dev *indio_dev = private;
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int ret;
> +	int dir;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_STATUS_2);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_int_status2\n");
> +		goto ack_intr_status;
> +	}
> +
> +	if (ret & 0x08)
> +		dir = IIO_EV_DIR_RISING;
> +	else
> +		dir = IIO_EV_DIR_FALLING;
> +
> +	if (ret & BMG160_ANY_MOTION_MASK)
> +		iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
> +							0,
> +							IIO_MOD_X_OR_Y_OR_Z,
> +							IIO_EV_TYPE_ROC,
> +							dir),
> +							data->timestamp);
> +
> +ack_intr_status:
> +	if (!data->dready_trigger_on) {
> +		ret = i2c_smbus_write_byte_data(data->client,
> +					BMG160_REG_INT_RST_LATCH,
> +					BMG160_INT_MODE_LATCH_INT |
> +					BMG160_INT_MODE_LATCH_RESET);
> +		if (ret < 0)
> +			dev_err(&data->client->dev,
> +				"Error writing reg_rst_latch\n");
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t bmg160_data_rdy_trig_poll(int irq, void *private)
> +{
> +	struct iio_dev *indio_dev = private;
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	data->timestamp = iio_get_time_ns();
> +
> +	if (data->dready_trigger_on)
> +		iio_trigger_poll(data->dready_trig);
> +	else if (data->motion_trigger_on)
> +		iio_trigger_poll(data->motion_trig);
> +
> +	if (data->ev_enable_state)
> +		return IRQ_WAKE_THREAD;
> +	else
> +		return IRQ_HANDLED;
> +
> +}
> +
> +static int bmg160_acpi_gpio_probe(struct i2c_client *client,
> +				  struct bmg160_data *data)
> +{
> +	const struct acpi_device_id *id;
> +	struct device *dev;
> +	struct gpio_desc *gpio;
> +	int ret;
> +
> +	if (!client)
> +		return -EINVAL;
> +
> +	dev = &client->dev;
> +	if (!ACPI_HANDLE(dev))
> +		return -ENODEV;
> +
> +	id = acpi_match_device(dev->driver->acpi_match_table, dev);
> +	if (!id)
> +		return -ENODEV;
> +
> +	/* data ready gpio interrupt pin */
> +	gpio = devm_gpiod_get_index(dev, BMG160_GPIO_NAME, 0);
> +	if (IS_ERR(gpio)) {
> +		dev_err(dev, "acpi gpio get index failed\n");
> +		return PTR_ERR(gpio);
> +	}
> +
> +	ret = gpiod_direction_input(gpio);
> +	if (ret)
> +		return ret;
> +
> +	ret = gpiod_to_irq(gpio);
> +
> +	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
> +
> +	return ret;
> +}
> +
> +static int bmg160_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	struct bmg160_data *data;
> +	struct iio_dev *indio_dev;
> +	int ret;
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	i2c_set_clientdata(client, indio_dev);
> +	data->client = client;
> +
> +	ret = bmg160_chip_init(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	mutex_init(&data->mutex);
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->channels = bmg160_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(bmg160_channels);
> +	indio_dev->name = BMG160_DRV_NAME;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->info = &bmg160_info;
> +
> +	if (client->irq <= 0)
> +		client->irq = bmg160_acpi_gpio_probe(client, data);
> +
> +	if (client->irq > 0) {
> +		ret = devm_request_threaded_irq(&client->dev,
> +						client->irq,
> +						bmg160_data_rdy_trig_poll,
> +						bmg160_event_handler,
> +						IRQF_TRIGGER_RISING,
> +						BMG160_IRQ_NAME,
> +						indio_dev);
> +		if (ret)
> +			return ret;
> +
> +		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
> +							   "%s-dev%d",
> +							   indio_dev->name,
> +							   indio_dev->id);
> +		if (!data->dready_trig)
> +			return -ENOMEM;
> +
> +		data->motion_trig = devm_iio_trigger_alloc(&client->dev,
> +							  "%s-any-motion-dev%d",
> +							  indio_dev->name,
> +							  indio_dev->id);
> +		if (!data->motion_trig)
> +			return -ENOMEM;
> +
> +		data->dready_trig->dev.parent = &client->dev;
> +		data->dready_trig->ops = &bmg160_trigger_ops;
> +		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
> +		ret = iio_trigger_register(data->dready_trig);
> +		if (ret)
> +			return ret;
> +
> +		data->motion_trig->dev.parent = &client->dev;
> +		data->motion_trig->ops = &bmg160_trigger_ops;
> +		iio_trigger_set_drvdata(data->motion_trig, indio_dev);
> +		ret = iio_trigger_register(data->motion_trig);
> +		if (ret) {
> +			data->motion_trig = NULL;
> +			goto err_trigger_unregister;
> +		}
> +
> +		ret = iio_triggered_buffer_setup(indio_dev,
> +						 NULL,
> +						 bmg160_trigger_handler,
> +						 NULL);
> +		if (ret < 0) {
> +			dev_err(&client->dev,
> +				"iio triggered buffer setup failed\n");
> +			goto err_trigger_unregister;
> +		}
> +	}
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "unable to register iio device\n");
> +		goto err_buffer_cleanup;
> +	}
> +
> +	ret = pm_runtime_set_active(&client->dev);
> +	if (ret)
> +		goto err_iio_unregister;
> +
> +	pm_runtime_enable(&client->dev);
> +	pm_runtime_set_autosuspend_delay(&client->dev,
> +					 BMG160_AUTO_SUSPEND_DELAY_MS);
> +	pm_runtime_use_autosuspend(&client->dev);
> +
> +	return 0;
> +
> +err_iio_unregister:
> +	iio_device_unregister(indio_dev);
> +err_buffer_cleanup:
> +	if (data->dready_trig)
> +		iio_triggered_buffer_cleanup(indio_dev);
> +err_trigger_unregister:
> +	if (data->dready_trig)
> +		iio_trigger_unregister(data->dready_trig);
> +	if (data->motion_trig)
> +		iio_trigger_unregister(data->motion_trig);
> +
> +	return ret;
> +}
> +
> +static int bmg160_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	pm_runtime_disable(&client->dev);
> +	pm_runtime_set_suspended(&client->dev);
> +	pm_runtime_put_noidle(&client->dev);
> +
> +	iio_device_unregister(indio_dev);
> +
> +	if (data->dready_trig) {
> +		iio_triggered_buffer_cleanup(indio_dev);
> +		iio_trigger_unregister(data->dready_trig);
> +		iio_trigger_unregister(data->motion_trig);
> +	}
> +
> +	mutex_lock(&data->mutex);
> +	bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
> +	mutex_unlock(&data->mutex);
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int bmg160_suspend(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	mutex_lock(&data->mutex);
> +	bmg160_set_mode(data, BMG160_MODE_SUSPEND);
> +	mutex_unlock(&data->mutex);
> +
> +	return 0;
> +}
> +
> +static int bmg160_resume(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	mutex_lock(&data->mutex);
> +	if (data->dready_trigger_on || data->motion_trigger_on ||
> +							data->ev_enable_state)
> +		bmg160_set_mode(data, BMG160_MODE_NORMAL);
> +	mutex_unlock(&data->mutex);
> +
> +	return 0;
> +}
> +#endif
> +
> +#ifdef CONFIG_PM_RUNTIME
> +static int bmg160_runtime_suspend(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +
> +	return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
> +}
> +
> +static int bmg160_runtime_resume(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> +	struct bmg160_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
> +	if (ret < 0)
> +		return ret;
> +
> +	msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
> +
> +	return 0;
> +}
> +#endif
> +
> +static const struct dev_pm_ops bmg160_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(bmg160_suspend, bmg160_resume)
> +	SET_RUNTIME_PM_OPS(bmg160_runtime_suspend,
> +			   bmg160_runtime_resume, NULL)
> +};
> +
> +static const struct acpi_device_id bmg160_acpi_match[] = {
> +	{"BMG0160", 0},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(acpi, bmg160_acpi_match);
> +
> +static const struct i2c_device_id bmg160_id[] = {
> +	{"bmg160", 0},
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, bmg160_id);
> +
> +static struct i2c_driver bmg160_driver = {
> +	.driver = {
> +		.name	= BMG160_DRV_NAME,
> +		.acpi_match_table = ACPI_PTR(bmg160_acpi_match),
> +		.pm	= &bmg160_pm_ops,
> +	},
> +	.probe		= bmg160_probe,
> +	.remove		= bmg160_remove,
> +	.id_table	= bmg160_id,
> +};
> +module_i2c_driver(bmg160_driver);
> +
> +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("BMG160 Gyro driver");
>

Re: [PATCH v3 1/2] iio:gyro:bmg160 Gyro Sensor driver

[Srinivas Pandruvada]

On 08/07/2014 03:39 AM, Jonathan Cameron wrote:
> On 05/08/14 22:57, Srinivas Pandruvada wrote:
>> This change implements support for BMG160 Gyro sensor. Although chip
>> has several advanced features, this change implements minimum set
>> required for using gyro sensor.
>>
>> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> One more query.  In the write_raw function you always enable then suspend the
> device.  The enable is safe, but if you have a write to the attributes
> whilst operating in triggered / buffered mode will it not disable the
> device?  It is perfectly permissible to ignore such a write (return -EBUSY)
> but I don't think you are doing so.
I will check on this.

Thanks,
Srinivas
>
> Otherwise, looks good to me.  Nice explanatory comments as well!
>> ---
>>   drivers/iio/gyro/Kconfig  |   11 +
>>   drivers/iio/gyro/Makefile |    1 +
>>   drivers/iio/gyro/bmg160.c | 1211 +++++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 1223 insertions(+)
>>   create mode 100644 drivers/iio/gyro/bmg160.c
>>
>> diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
>> index ac2d69e..d630ae9 100644
>> --- a/drivers/iio/gyro/Kconfig
>> +++ b/drivers/iio/gyro/Kconfig
>> @@ -50,6 +50,17 @@ config ADXRS450
>>   	  This driver can also be built as a module.  If so, the module
>>   	  will be called adxrs450.
>>
>> +config BMG160
>> +	tristate "BOSCH BMG160 Gyro Sensor"
>> +	depends on I2C
>> +	select IIO_TRIGGERED_BUFFER if IIO_BUFFER
>> +	help
>> +	  Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
>> +	  driver.
>> +
>> +	  This driver can also be built as a module.  If so, the module
>> +	  will be called bmg160.
>> +
>>   config HID_SENSOR_GYRO_3D
>>   	depends on HID_SENSOR_HUB
>>   	select IIO_BUFFER
>> diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
>> index 2f2752a..36a3877 100644
>> --- a/drivers/iio/gyro/Makefile
>> +++ b/drivers/iio/gyro/Makefile
>> @@ -8,6 +8,7 @@ obj-$(CONFIG_ADIS16130) += adis16130.o
>>   obj-$(CONFIG_ADIS16136) += adis16136.o
>>   obj-$(CONFIG_ADIS16260) += adis16260.o
>>   obj-$(CONFIG_ADXRS450) += adxrs450.o
>> +obj-$(CONFIG_BMG160) += bmg160.o
>>
>>   obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
>>
>> diff --git a/drivers/iio/gyro/bmg160.c b/drivers/iio/gyro/bmg160.c
>> new file mode 100644
>> index 0000000..80f92a6
>> --- /dev/null
>> +++ b/drivers/iio/gyro/bmg160.c
>> @@ -0,0 +1,1211 @@
>> +/*
>> + * BMG160 Gyro Sensor driver
>> + * Copyright (c) 2014, Intel Corporation.
>> + *
>> + * This program is free software; you can redistribute it and/or modify it
>> + * under the terms and conditions of the GNU General Public License,
>> + * version 2, as published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope it will be useful, but WITHOUT
>> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
>> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
>> + * more details.
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/i2c.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/delay.h>
>> +#include <linux/slab.h>
>> +#include <linux/acpi.h>
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/pm.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +#include <linux/iio/buffer.h>
>> +#include <linux/iio/trigger.h>
>> +#include <linux/iio/events.h>
>> +#include <linux/iio/trigger_consumer.h>
>> +#include <linux/iio/triggered_buffer.h>
>> +
>> +#define BMG160_DRV_NAME		"bmg160"
>> +#define BMG160_IRQ_NAME		"bmg160_event"
>> +#define BMG160_GPIO_NAME		"gpio_int"
>> +
>> +#define BMG160_REG_CHIP_ID		0x00
>> +#define BMG160_CHIP_ID_VAL		0x0F
>> +
>> +#define BMG160_REG_PMU_LPW		0x11
>> +#define BMG160_MODE_NORMAL		0x00
>> +#define BMG160_MODE_DEEP_SUSPEND	0x20
>> +#define BMG160_MODE_SUSPEND		0x80
>> +
>> +#define BMG160_REG_RANGE		0x0F
>> +
>> +#define BMG160_RANGE_2000DPS		0
>> +#define BMG160_RANGE_1000DPS		1
>> +#define BMG160_RANGE_500DPS		2
>> +#define BMG160_RANGE_250DPS		3
>> +#define BMG160_RANGE_125DPS		4
>> +
>> +#define BMG160_REG_PMU_BW		0x10
>> +#define BMG160_NO_FILTER		0
>> +#define BMG160_DEF_BW			100
>> +
>> +#define BMG160_REG_INT_MAP_0		0x17
>> +#define BMG160_INT_MAP_0_BIT_ANY	BIT(1)
>> +
>> +#define BMG160_REG_INT_MAP_1		0x18
>> +#define BMG160_INT_MAP_1_BIT_NEW_DATA	BIT(0)
>> +
>> +#define BMG160_REG_INT_RST_LATCH	0x21
>> +#define BMG160_INT_MODE_LATCH_RESET	0x80
>> +#define BMG160_INT_MODE_LATCH_INT	0x0F
>> +#define BMG160_INT_MODE_NON_LATCH_INT	0x00
>> +
>> +#define BMG160_REG_INT_EN_0		0x15
>> +#define BMG160_DATA_ENABLE_INT		BIT(7)
>> +
>> +#define BMG160_REG_XOUT_L		0x02
>> +#define BMG160_AXIS_TO_REG(axis)	(BMG160_REG_XOUT_L + (axis * 2))
>> +
>> +#define BMG160_REG_SLOPE_THRES		0x1B
>> +#define BMG160_SLOPE_THRES_MASK	0x0F
>> +
>> +#define BMG160_REG_MOTION_INTR		0x1C
>> +#define BMG160_INT_MOTION_X		BIT(0)
>> +#define BMG160_INT_MOTION_Y		BIT(1)
>> +#define BMG160_INT_MOTION_Z		BIT(2)
>> +#define BMG160_ANY_DUR_MASK		0x30
>> +#define BMG160_ANY_DUR_SHIFT		4
>> +
>> +#define BMG160_REG_INT_STATUS_2	0x0B
>> +#define BMG160_ANY_MOTION_MASK		0x07
>> +
>> +#define BMG160_REG_TEMP		0x08
>> +#define BMG160_TEMP_CENTER_VAL		23
>> +
>> +#define BMG160_MAX_STARTUP_TIME_MS	80
>> +
>> +#define BMG160_AUTO_SUSPEND_DELAY_MS	2000
>> +
>> +struct bmg160_data {
>> +	struct i2c_client *client;
>> +	struct iio_trigger *dready_trig;
>> +	struct iio_trigger *motion_trig;
>> +	struct mutex mutex;
>> +	s16 buffer[8];
>> +	u8 bw_bits;
>> +	u32 dps_range;
>> +	int ev_enable_state;
>> +	int slope_thres;
>> +	bool dready_trigger_on;
>> +	bool motion_trigger_on;
>> +	int64_t timestamp;
>> +};
>> +
>> +enum bmg160_axis {
>> +	AXIS_X,
>> +	AXIS_Y,
>> +	AXIS_Z,
>> +};
>> +
>> +static const struct {
>> +	int val;
>> +	int bw_bits;
>> +} bmg160_samp_freq_table[] = { {100, 0x07},
>> +			       {200, 0x06},
>> +			       {400, 0x03},
>> +			       {1000, 0x02},
>> +			       {2000, 0x01} };
>> +
>> +static const struct {
>> +	int scale;
>> +	int dps_range;
>> +} bmg160_scale_table[] = { { 1065, BMG160_RANGE_2000DPS},
>> +			   { 532, BMG160_RANGE_1000DPS},
>> +			   { 266, BMG160_RANGE_500DPS},
>> +			   { 133, BMG160_RANGE_250DPS},
>> +			   { 66, BMG160_RANGE_125DPS} };
>> +
>> +static int bmg160_set_mode(struct bmg160_data *data, u8 mode)
>> +{
>> +	int ret;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_PMU_LPW, mode);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_pmu_lpw\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_convert_freq_to_bit(int val)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>> +		if (bmg160_samp_freq_table[i].val == val)
>> +			return bmg160_samp_freq_table[i].bw_bits;
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_set_bw(struct bmg160_data *data, int val)
>> +{
>> +	int ret;
>> +	int bw_bits;
>> +
>> +	bw_bits = bmg160_convert_freq_to_bit(val);
>> +	if (bw_bits < 0)
>> +		return bw_bits;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client, BMG160_REG_PMU_BW,
>> +					bw_bits);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_pmu_bw\n");
>> +		return ret;
>> +	}
>> +
>> +	data->bw_bits = bw_bits;
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_chip_init(struct bmg160_data *data)
>> +{
>> +	int ret;
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_CHIP_ID);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_chip_id\n");
>> +		return ret;
>> +	}
>> +
>> +	dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
>> +	if (ret != BMG160_CHIP_ID_VAL) {
>> +		dev_err(&data->client->dev, "invalid chip %x\n", ret);
>> +		return -ENODEV;
>> +	}
>> +
>> +	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* Wait upto 500 ms to be ready after changing mode */
>> +	usleep_range(500, 1000);
>> +
>> +	/* Set Bandwidth */
>> +	ret = bmg160_set_bw(data, BMG160_DEF_BW);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* Set Default Range */
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_RANGE,
>> +					BMG160_RANGE_500DPS);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_range\n");
>> +		return ret;
>> +	}
>> +	data->dps_range = BMG160_RANGE_500DPS;
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_SLOPE_THRES);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_slope_thres\n");
>> +		return ret;
>> +	}
>> +	data->slope_thres = ret;
>> +
>> +	/* Set default interrupt mode */
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_RST_LATCH,
>> +					BMG160_INT_MODE_LATCH_INT |
>> +					BMG160_INT_MODE_LATCH_RESET);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev,
>> +			"Error writing reg_motion_intr\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_set_power_state(struct bmg160_data *data, bool on)
>> +{
>> +	int ret;
>> +
>> +	if (on)
>> +		ret = pm_runtime_get_sync(&data->client->dev);
>> +	else {
>> +		pm_runtime_mark_last_busy(&data->client->dev);
>> +		ret = pm_runtime_put_autosuspend(&data->client->dev);
>> +	}
>> +
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev,
>> +			"Failed: bmg160_set_power_state for %d\n", on);
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_setup_any_motion_interrupt(struct bmg160_data *data,
>> +					     bool status)
>> +{
>> +	int ret;
>> +
>> +	/* Enable/Disable INT_MAP0 mapping */
>> +	ret = i2c_smbus_read_byte_data(data->client,  BMG160_REG_INT_MAP_0);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_int_map0\n");
>> +		return ret;
>> +	}
>> +	if (status)
>> +		ret |= BMG160_INT_MAP_0_BIT_ANY;
>> +	else
>> +		ret &= ~BMG160_INT_MAP_0_BIT_ANY;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_MAP_0,
>> +					ret);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_map0\n");
>> +		return ret;
>> +	}
>> +
>> +	/* Enable/Disable slope interrupts */
>> +	if (status) {
>> +		/* Update slope thres */
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_SLOPE_THRES,
>> +						data->slope_thres);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_slope_thres\n");
>> +			return ret;
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_MOTION_INTR,
>> +						BMG160_INT_MOTION_X |
>> +						BMG160_INT_MOTION_Y |
>> +						BMG160_INT_MOTION_Z);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_motion_intr\n");
>> +			return ret;
>> +		}
>> +
>> +		/*
>> +		 * New data interrupt is always non-latched,
>> +		 * which will have higher priority, so no need
>> +		 * to set latched mode, we will be flooded anyway with INTR
>> +		 */
>> +		if (!data->dready_trigger_on) {
>> +			ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_RST_LATCH,
>> +						BMG160_INT_MODE_LATCH_INT |
>> +						BMG160_INT_MODE_LATCH_RESET);
>> +			if (ret < 0) {
>> +				dev_err(&data->client->dev,
>> +					"Error writing reg_rst_latch\n");
>> +				return ret;
>> +			}
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						BMG160_DATA_ENABLE_INT);
>> +
>> +	} else
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						0);
>> +
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_setup_new_data_interrupt(struct bmg160_data *data,
>> +					   bool status)
>> +{
>> +	int ret;
>> +
>> +	/* Enable/Disable INT_MAP1 mapping */
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_MAP_1);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_int_map1\n");
>> +		return ret;
>> +	}
>> +
>> +	if (status)
>> +		ret |= BMG160_INT_MAP_1_BIT_NEW_DATA;
>> +	else
>> +		ret &= ~BMG160_INT_MAP_1_BIT_NEW_DATA;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_MAP_1,
>> +					ret);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_map1\n");
>> +		return ret;
>> +	}
>> +
>> +	if (status) {
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_RST_LATCH,
>> +						BMG160_INT_MODE_NON_LATCH_INT |
>> +						BMG160_INT_MODE_LATCH_RESET);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_rst_latch\n");
>> +				return ret;
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						BMG160_DATA_ENABLE_INT);
>> +
>> +	} else {
>> +		/* Restore interrupt mode */
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_RST_LATCH,
>> +						BMG160_INT_MODE_LATCH_INT |
>> +						BMG160_INT_MODE_LATCH_RESET);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_rst_latch\n");
>> +				return ret;
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						0);
>> +	}
>> +
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_get_bw(struct bmg160_data *data, int *val)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>> +		if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
>> +			*val = bmg160_samp_freq_table[i].val;
>> +			return IIO_VAL_INT;
>> +		}
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_set_scale(struct bmg160_data *data, int val)
>> +{
>> +	int ret, i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>> +		if (bmg160_scale_table[i].scale == val) {
>> +			ret = i2c_smbus_write_byte_data(
>> +					data->client,
>> +					BMG160_REG_RANGE,
>> +					bmg160_scale_table[i].dps_range);
>> +			if (ret < 0) {
>> +				dev_err(&data->client->dev,
>> +					"Error writing reg_range\n");
>> +				return ret;
>> +			}
>> +			data->dps_range = bmg160_scale_table[i].dps_range;
>> +			return 0;
>> +		}
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_get_temp(struct bmg160_data *data, int *val)
>> +{
>> +	int ret;
>> +
>> +	mutex_lock(&data->mutex);
>> +	ret = bmg160_set_power_state(data, true);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_TEMP);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_temp\n");
>> +		bmg160_set_power_state(data, false);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	*val = sign_extend32(ret, 7);
>> +	ret = bmg160_set_power_state(data, false);
>> +	mutex_unlock(&data->mutex);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	return IIO_VAL_INT;
>> +}
>> +
>> +static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
>> +{
>> +	int ret;
>> +
>> +	mutex_lock(&data->mutex);
>> +	ret = bmg160_set_power_state(data, true);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	ret = i2c_smbus_read_word_data(data->client, BMG160_AXIS_TO_REG(axis));
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading axis %d\n", axis);
>> +		bmg160_set_power_state(data, false);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	*val = sign_extend32(ret, 15);
>> +	ret = bmg160_set_power_state(data, false);
>> +	mutex_unlock(&data->mutex);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	return IIO_VAL_INT;
>> +}
>> +
>> +static int bmg160_read_raw(struct iio_dev *indio_dev,
>> +			   struct iio_chan_spec const *chan,
>> +			   int *val, int *val2, long mask)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_RAW:
>> +		switch (chan->type) {
>> +		case IIO_TEMP:
>> +			return bmg160_get_temp(data, val);
>> +		case IIO_ANGL_VEL:
>> +			if (iio_buffer_enabled(indio_dev))
>> +				return -EBUSY;
>> +			else
>> +				return bmg160_get_axis(data, chan->scan_index,
>> +						       val);
>> +		default:
>> +			return -EINVAL;
>> +		}
>> +	case IIO_CHAN_INFO_OFFSET:
>> +		if (chan->type == IIO_TEMP) {
>> +			*val = BMG160_TEMP_CENTER_VAL;
>> +			return IIO_VAL_INT;
>> +		} else
>> +			return -EINVAL;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		*val = 0;
>> +		switch (chan->type) {
>> +		case IIO_TEMP:
>> +			*val2 = 500000;
>> +			return IIO_VAL_INT_PLUS_MICRO;
>> +		case IIO_ANGL_VEL:
>> +		{
>> +			int i;
>> +
>> +			for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>> +				if (bmg160_scale_table[i].dps_range ==
>> +							data->dps_range) {
>> +					*val2 = bmg160_scale_table[i].scale;
>> +					return IIO_VAL_INT_PLUS_MICRO;
>> +				}
>> +			}
>> +			return -EINVAL;
>> +		}
>> +		default:
>> +			return -EINVAL;
>> +		}
>> +	case IIO_CHAN_INFO_SAMP_FREQ:
>> +		*val2 = 0;
>> +		mutex_lock(&data->mutex);
>> +		ret = bmg160_get_bw(data, val);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +}
>> +
>> +static int bmg160_write_raw(struct iio_dev *indio_dev,
>> +			    struct iio_chan_spec const *chan,
>> +			    int val, int val2, long mask)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_SAMP_FREQ:
>> +		mutex_lock(&data->mutex);
>> +		/*
>> +		 * Section 4.2 of spec
>> +		 * In suspend mode, the only supported operations are reading
>> +		 * registers as well as writing to the (0x14) softreset
>> +		 * register. Since we will be in suspend mode by default, change
>> +		 * mode to power on for other writes.
>> +		 */
>> +		ret = bmg160_set_power_state(data, true);
>> +		if (ret < 0) {
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_bw(data, val);
>> +		if (ret < 0) {
>> +			bmg160_set_power_state(data, false);
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_power_state(data, false);
> Could this end up disabling the part when in triggered mode?
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		if (val)
>> +			return -EINVAL;
>> +
>> +		mutex_lock(&data->mutex);
>> +		/* Refer to comments above for the suspend mode ops */
>> +		ret = bmg160_set_power_state(data, true);
>> +		if (ret < 0) {
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_scale(data, val2);
>> +		if (ret < 0) {
>> +			bmg160_set_power_state(data, false);
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_power_state(data, false);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_read_event(struct iio_dev *indio_dev,
>> +			     const struct iio_chan_spec *chan,
>> +			     enum iio_event_type type,
>> +			     enum iio_event_direction dir,
>> +			     enum iio_event_info info,
>> +			     int *val, int *val2)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	*val2 = 0;
>> +	switch (info) {
>> +	case IIO_EV_INFO_VALUE:
>> +		*val = data->slope_thres & BMG160_SLOPE_THRES_MASK;
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return IIO_VAL_INT;
>> +}
>> +
>> +static int bmg160_write_event(struct iio_dev *indio_dev,
>> +			      const struct iio_chan_spec *chan,
>> +			      enum iio_event_type type,
>> +			      enum iio_event_direction dir,
>> +			      enum iio_event_info info,
>> +			      int val, int val2)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	switch (info) {
>> +	case IIO_EV_INFO_VALUE:
>> +		if (data->ev_enable_state)
>> +			return -EBUSY;
>> +		data->slope_thres &= ~BMG160_SLOPE_THRES_MASK;
>> +		data->slope_thres |= (val & BMG160_SLOPE_THRES_MASK);
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_read_event_config(struct iio_dev *indio_dev,
>> +				    const struct iio_chan_spec *chan,
>> +				    enum iio_event_type type,
>> +				    enum iio_event_direction dir)
>> +{
>> +
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	return data->ev_enable_state;
>> +}
>> +
>> +static int bmg160_write_event_config(struct iio_dev *indio_dev,
>> +				     const struct iio_chan_spec *chan,
>> +				     enum iio_event_type type,
>> +				     enum iio_event_direction dir,
>> +				     int state)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	if (state && data->ev_enable_state)
>> +		return 0;
>> +
>> +	mutex_lock(&data->mutex);
>> +
>> +	if (!state && data->motion_trigger_on) {
>> +		data->ev_enable_state = 0;
>> +		mutex_unlock(&data->mutex);
>> +		return 0;
>> +	}
>> +	/*
>> +	 * We will expect the enable and disable to do operation in
>> +	 * in reverse order. This will happen here anyway as our
>> +	 * resume operation uses sync mode runtime pm calls, the
>> +	 * suspend operation will be delayed by autosuspend delay
>> +	 * So the disable operation will still happen in reverse of
>> +	 * enable operation. When runtime pm is disabled the mode
>> +	 * is always on so sequence doesn't matter
>> +	 */
> Thanks for the detailed comment!
>> +	ret = bmg160_set_power_state(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	ret =  bmg160_setup_any_motion_interrupt(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	data->ev_enable_state = state;
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_validate_trigger(struct iio_dev *indio_dev,
>> +				   struct iio_trigger *trig)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	if (data->dready_trig != trig && data->motion_trig != trig)
>> +		return -EINVAL;
>> +
>> +	return 0;
>> +}
>> +
>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 400 1000 2000");
>> +
>> +static IIO_CONST_ATTR(in_anglvel_scale_available,
>> +		      "0.001065 0.000532 0.000266 0.000133 0.000066");
>> +
>> +static struct attribute *bmg160_attributes[] = {
>> +	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
>> +	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
>> +	NULL,
>> +};
>> +
>> +static const struct attribute_group bmg160_attrs_group = {
>> +	.attrs = bmg160_attributes,
>> +};
>> +
>> +static const struct iio_event_spec bmg160_event = {
>> +		.type = IIO_EV_TYPE_ROC,
>> +		.dir = IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING,
>> +		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
>> +				       BIT(IIO_EV_INFO_ENABLE)
>> +};
>> +
>> +#define BMG160_CHANNEL(_axis) {					\
>> +	.type = IIO_ANGL_VEL,						\
>> +	.modified = 1,							\
>> +	.channel2 = IIO_MOD_##_axis,					\
>> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
>> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
>> +				    BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
>> +	.scan_index = AXIS_##_axis,					\
>> +	.scan_type = {							\
>> +		.sign = 's',						\
>> +		.realbits = 16,					\
>> +		.storagebits = 16,					\
>> +	},								\
>> +	.event_spec = &bmg160_event,					\
>> +	.num_event_specs = 1						\
>> +}
>> +
>> +static const struct iio_chan_spec bmg160_channels[] = {
>> +	{
>> +		.type = IIO_TEMP,
>> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> +				      BIT(IIO_CHAN_INFO_SCALE) |
>> +				      BIT(IIO_CHAN_INFO_OFFSET),
>> +		.scan_index = -1,
>> +	},
>> +	BMG160_CHANNEL(X),
>> +	BMG160_CHANNEL(Y),
>> +	BMG160_CHANNEL(Z),
>> +	IIO_CHAN_SOFT_TIMESTAMP(3),
>> +};
>> +
>> +static const struct iio_info bmg160_info = {
>> +	.attrs			= &bmg160_attrs_group,
>> +	.read_raw		= bmg160_read_raw,
>> +	.write_raw		= bmg160_write_raw,
>> +	.read_event_value	= bmg160_read_event,
>> +	.write_event_value	= bmg160_write_event,
>> +	.write_event_config	= bmg160_write_event_config,
>> +	.read_event_config	= bmg160_read_event_config,
>> +	.validate_trigger	= bmg160_validate_trigger,
>> +	.driver_module		= THIS_MODULE,
>> +};
>> +
>> +static irqreturn_t bmg160_trigger_handler(int irq, void *p)
>> +{
>> +	struct iio_poll_func *pf = p;
>> +	struct iio_dev *indio_dev = pf->indio_dev;
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int bit, ret, i = 0;
>> +
>> +	mutex_lock(&data->mutex);
>> +	for_each_set_bit(bit, indio_dev->buffer->scan_mask,
>> +			 indio_dev->masklength) {
>> +		ret = i2c_smbus_read_word_data(data->client,
>> +					       BMG160_AXIS_TO_REG(bit));
>> +		if (ret < 0) {
>> +			mutex_unlock(&data->mutex);
>> +			goto err;
>> +		}
>> +		data->buffer[i++] = ret;
>> +	}
>> +	mutex_unlock(&data->mutex);
>> +
>> +	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
>> +					   data->timestamp);
>> +err:
>> +	iio_trigger_notify_done(indio_dev->trig);
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int bmg160_trig_try_reen(struct iio_trigger *trig)
>> +{
>> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	/* new data interrupts don't need ack */
>> +	if (data->dready_trigger_on)
>> +		return 0;
>> +
>> +	/* Set latched mode interrupt and clear any latched interrupt */
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_RST_LATCH,
>> +					BMG160_INT_MODE_LATCH_INT |
>> +					BMG160_INT_MODE_LATCH_RESET);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_data_rdy_trigger_set_state(struct iio_trigger *trig,
>> +					     bool state)
>> +{
>> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	mutex_lock(&data->mutex);
>> +
>> +	if (!state && data->ev_enable_state && data->motion_trigger_on) {
>> +		data->motion_trigger_on = false;
>> +		mutex_unlock(&data->mutex);
>> +		return 0;
>> +	}
>> +
>> +	/*
>> +	 * Refer to comment in bmg160_write_event_config for
>> +	 * enable/disable operation order
>> +	 */
>> +	ret = bmg160_set_power_state(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +	if (data->motion_trig == trig)
>> +		ret =  bmg160_setup_any_motion_interrupt(data, state);
>> +	else
>> +		ret = bmg160_setup_new_data_interrupt(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +	if (data->motion_trig == trig)
>> +		data->motion_trigger_on = state;
>> +	else
>> +		data->dready_trigger_on = state;
>> +
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct iio_trigger_ops bmg160_trigger_ops = {
>> +	.set_trigger_state = bmg160_data_rdy_trigger_set_state,
>> +	.try_reenable = bmg160_trig_try_reen,
>> +	.owner = THIS_MODULE,
>> +};
>> +
>> +static irqreturn_t bmg160_event_handler(int irq, void *private)
>> +{
>> +	struct iio_dev *indio_dev = private;
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +	int dir;
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_STATUS_2);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_int_status2\n");
>> +		goto ack_intr_status;
>> +	}
>> +
>> +	if (ret & 0x08)
>> +		dir = IIO_EV_DIR_RISING;
>> +	else
>> +		dir = IIO_EV_DIR_FALLING;
>> +
>> +	if (ret & BMG160_ANY_MOTION_MASK)
>> +		iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
>> +							0,
>> +							IIO_MOD_X_OR_Y_OR_Z,
>> +							IIO_EV_TYPE_ROC,
>> +							dir),
>> +							data->timestamp);
>> +
>> +ack_intr_status:
>> +	if (!data->dready_trigger_on) {
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_RST_LATCH,
>> +					BMG160_INT_MODE_LATCH_INT |
>> +					BMG160_INT_MODE_LATCH_RESET);
>> +		if (ret < 0)
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_rst_latch\n");
>> +	}
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static irqreturn_t bmg160_data_rdy_trig_poll(int irq, void *private)
>> +{
>> +	struct iio_dev *indio_dev = private;
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	data->timestamp = iio_get_time_ns();
>> +
>> +	if (data->dready_trigger_on)
>> +		iio_trigger_poll(data->dready_trig);
>> +	else if (data->motion_trigger_on)
>> +		iio_trigger_poll(data->motion_trig);
>> +
>> +	if (data->ev_enable_state)
>> +		return IRQ_WAKE_THREAD;
>> +	else
>> +		return IRQ_HANDLED;
>> +
>> +}
>> +
>> +static int bmg160_acpi_gpio_probe(struct i2c_client *client,
>> +				  struct bmg160_data *data)
>> +{
>> +	const struct acpi_device_id *id;
>> +	struct device *dev;
>> +	struct gpio_desc *gpio;
>> +	int ret;
>> +
>> +	if (!client)
>> +		return -EINVAL;
>> +
>> +	dev = &client->dev;
>> +	if (!ACPI_HANDLE(dev))
>> +		return -ENODEV;
>> +
>> +	id = acpi_match_device(dev->driver->acpi_match_table, dev);
>> +	if (!id)
>> +		return -ENODEV;
>> +
>> +	/* data ready gpio interrupt pin */
>> +	gpio = devm_gpiod_get_index(dev, BMG160_GPIO_NAME, 0);
>> +	if (IS_ERR(gpio)) {
>> +		dev_err(dev, "acpi gpio get index failed\n");
>> +		return PTR_ERR(gpio);
>> +	}
>> +
>> +	ret = gpiod_direction_input(gpio);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = gpiod_to_irq(gpio);
>> +
>> +	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
>> +
>> +	return ret;
>> +}
>> +
>> +static int bmg160_probe(struct i2c_client *client,
>> +			const struct i2c_device_id *id)
>> +{
>> +	struct bmg160_data *data;
>> +	struct iio_dev *indio_dev;
>> +	int ret;
>> +
>> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>> +	if (!indio_dev)
>> +		return -ENOMEM;
>> +
>> +	data = iio_priv(indio_dev);
>> +	i2c_set_clientdata(client, indio_dev);
>> +	data->client = client;
>> +
>> +	ret = bmg160_chip_init(data);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	mutex_init(&data->mutex);
>> +
>> +	indio_dev->dev.parent = &client->dev;
>> +	indio_dev->channels = bmg160_channels;
>> +	indio_dev->num_channels = ARRAY_SIZE(bmg160_channels);
>> +	indio_dev->name = BMG160_DRV_NAME;
>> +	indio_dev->modes = INDIO_DIRECT_MODE;
>> +	indio_dev->info = &bmg160_info;
>> +
>> +	if (client->irq <= 0)
>> +		client->irq = bmg160_acpi_gpio_probe(client, data);
>> +
>> +	if (client->irq > 0) {
>> +		ret = devm_request_threaded_irq(&client->dev,
>> +						client->irq,
>> +						bmg160_data_rdy_trig_poll,
>> +						bmg160_event_handler,
>> +						IRQF_TRIGGER_RISING,
>> +						BMG160_IRQ_NAME,
>> +						indio_dev);
>> +		if (ret)
>> +			return ret;
>> +
>> +		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
>> +							   "%s-dev%d",
>> +							   indio_dev->name,
>> +							   indio_dev->id);
>> +		if (!data->dready_trig)
>> +			return -ENOMEM;
>> +
>> +		data->motion_trig = devm_iio_trigger_alloc(&client->dev,
>> +							  "%s-any-motion-dev%d",
>> +							  indio_dev->name,
>> +							  indio_dev->id);
>> +		if (!data->motion_trig)
>> +			return -ENOMEM;
>> +
>> +		data->dready_trig->dev.parent = &client->dev;
>> +		data->dready_trig->ops = &bmg160_trigger_ops;
>> +		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
>> +		ret = iio_trigger_register(data->dready_trig);
>> +		if (ret)
>> +			return ret;
>> +
>> +		data->motion_trig->dev.parent = &client->dev;
>> +		data->motion_trig->ops = &bmg160_trigger_ops;
>> +		iio_trigger_set_drvdata(data->motion_trig, indio_dev);
>> +		ret = iio_trigger_register(data->motion_trig);
>> +		if (ret) {
>> +			data->motion_trig = NULL;
>> +			goto err_trigger_unregister;
>> +		}
>> +
>> +		ret = iio_triggered_buffer_setup(indio_dev,
>> +						 NULL,
>> +						 bmg160_trigger_handler,
>> +						 NULL);
>> +		if (ret < 0) {
>> +			dev_err(&client->dev,
>> +				"iio triggered buffer setup failed\n");
>> +			goto err_trigger_unregister;
>> +		}
>> +	}
>> +
>> +	ret = iio_device_register(indio_dev);
>> +	if (ret < 0) {
>> +		dev_err(&client->dev, "unable to register iio device\n");
>> +		goto err_buffer_cleanup;
>> +	}
>> +
>> +	ret = pm_runtime_set_active(&client->dev);
>> +	if (ret)
>> +		goto err_iio_unregister;
>> +
>> +	pm_runtime_enable(&client->dev);
>> +	pm_runtime_set_autosuspend_delay(&client->dev,
>> +					 BMG160_AUTO_SUSPEND_DELAY_MS);
>> +	pm_runtime_use_autosuspend(&client->dev);
>> +
>> +	return 0;
>> +
>> +err_iio_unregister:
>> +	iio_device_unregister(indio_dev);
>> +err_buffer_cleanup:
>> +	if (data->dready_trig)
>> +		iio_triggered_buffer_cleanup(indio_dev);
>> +err_trigger_unregister:
>> +	if (data->dready_trig)
>> +		iio_trigger_unregister(data->dready_trig);
>> +	if (data->motion_trig)
>> +		iio_trigger_unregister(data->motion_trig);
>> +
>> +	return ret;
>> +}
>> +
>> +static int bmg160_remove(struct i2c_client *client)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	pm_runtime_disable(&client->dev);
>> +	pm_runtime_set_suspended(&client->dev);
>> +	pm_runtime_put_noidle(&client->dev);
>> +
>> +	iio_device_unregister(indio_dev);
>> +
>> +	if (data->dready_trig) {
>> +		iio_triggered_buffer_cleanup(indio_dev);
>> +		iio_trigger_unregister(data->dready_trig);
>> +		iio_trigger_unregister(data->motion_trig);
>> +	}
>> +
>> +	mutex_lock(&data->mutex);
>> +	bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +#ifdef CONFIG_PM_SLEEP
>> +static int bmg160_suspend(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	mutex_lock(&data->mutex);
>> +	bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_resume(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	mutex_lock(&data->mutex);
>> +	if (data->dready_trigger_on || data->motion_trigger_on ||
>> +							data->ev_enable_state)
>> +		bmg160_set_mode(data, BMG160_MODE_NORMAL);
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +#endif
>> +
>> +#ifdef CONFIG_PM_RUNTIME
>> +static int bmg160_runtime_suspend(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>> +}
>> +
>> +static int bmg160_runtime_resume(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
>> +
>> +	return 0;
>> +}
>> +#endif
>> +
>> +static const struct dev_pm_ops bmg160_pm_ops = {
>> +	SET_SYSTEM_SLEEP_PM_OPS(bmg160_suspend, bmg160_resume)
>> +	SET_RUNTIME_PM_OPS(bmg160_runtime_suspend,
>> +			   bmg160_runtime_resume, NULL)
>> +};
>> +
>> +static const struct acpi_device_id bmg160_acpi_match[] = {
>> +	{"BMG0160", 0},
>> +	{ },
>> +};
>> +MODULE_DEVICE_TABLE(acpi, bmg160_acpi_match);
>> +
>> +static const struct i2c_device_id bmg160_id[] = {
>> +	{"bmg160", 0},
>> +	{}
>> +};
>> +
>> +MODULE_DEVICE_TABLE(i2c, bmg160_id);
>> +
>> +static struct i2c_driver bmg160_driver = {
>> +	.driver = {
>> +		.name	= BMG160_DRV_NAME,
>> +		.acpi_match_table = ACPI_PTR(bmg160_acpi_match),
>> +		.pm	= &bmg160_pm_ops,
>> +	},
>> +	.probe		= bmg160_probe,
>> +	.remove		= bmg160_remove,
>> +	.id_table	= bmg160_id,
>> +};
>> +module_i2c_driver(bmg160_driver);
>> +
>> +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_DESCRIPTION("BMG160 Gyro driver");
>>

Re: [PATCH v3 1/2] iio:gyro:bmg160 Gyro Sensor driver

[Srinivas Pandruvada]

On 08/07/2014 03:39 AM, Jonathan Cameron wrote:
> On 05/08/14 22:57, Srinivas Pandruvada wrote:
>> This change implements support for BMG160 Gyro sensor. Although chip
>> has several advanced features, this change implements minimum set
>> required for using gyro sensor.
>>
>> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> One more query.  In the write_raw function you always enable then suspend the
> device.  The enable is safe, but if you have a write to the attributes
> whilst operating in triggered / buffered mode will it not disable the
> device?  It is perfectly permissible to ignore such a write (return -EBUSY)
> but I don't think you are doing so.
>

I tested this. When trigger/events are active then first call to 
bmg160_set_power_state will increment runtime pm refcount and also 
execute runtime resume to change the mode to NORMAL.
But when write_raw is called while the trigger/events are active the 
runtime PM refcount is incremented since it was already more than 0, so 
the resume is not actually called. When at the end of write_raw 
bmg160_set_power_state to turn off, the ref count is simply decremented, 
but since it is not zero, runtime suspend will not be called.

Thanks,
Srinivas

> Otherwise, looks good to me.  Nice explanatory comments as well!
>> ---
>>   drivers/iio/gyro/Kconfig  |   11 +
>>   drivers/iio/gyro/Makefile |    1 +
>>   drivers/iio/gyro/bmg160.c | 1211 +++++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 1223 insertions(+)
>>   create mode 100644 drivers/iio/gyro/bmg160.c
>>
>> diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
>> index ac2d69e..d630ae9 100644
>> --- a/drivers/iio/gyro/Kconfig
>> +++ b/drivers/iio/gyro/Kconfig
>> @@ -50,6 +50,17 @@ config ADXRS450
>>   	  This driver can also be built as a module.  If so, the module
>>   	  will be called adxrs450.
>>
>> +config BMG160
>> +	tristate "BOSCH BMG160 Gyro Sensor"
>> +	depends on I2C
>> +	select IIO_TRIGGERED_BUFFER if IIO_BUFFER
>> +	help
>> +	  Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
>> +	  driver.
>> +
>> +	  This driver can also be built as a module.  If so, the module
>> +	  will be called bmg160.
>> +
>>   config HID_SENSOR_GYRO_3D
>>   	depends on HID_SENSOR_HUB
>>   	select IIO_BUFFER
>> diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
>> index 2f2752a..36a3877 100644
>> --- a/drivers/iio/gyro/Makefile
>> +++ b/drivers/iio/gyro/Makefile
>> @@ -8,6 +8,7 @@ obj-$(CONFIG_ADIS16130) += adis16130.o
>>   obj-$(CONFIG_ADIS16136) += adis16136.o
>>   obj-$(CONFIG_ADIS16260) += adis16260.o
>>   obj-$(CONFIG_ADXRS450) += adxrs450.o
>> +obj-$(CONFIG_BMG160) += bmg160.o
>>
>>   obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
>>
>> diff --git a/drivers/iio/gyro/bmg160.c b/drivers/iio/gyro/bmg160.c
>> new file mode 100644
>> index 0000000..80f92a6
>> --- /dev/null
>> +++ b/drivers/iio/gyro/bmg160.c
>> @@ -0,0 +1,1211 @@
>> +/*
>> + * BMG160 Gyro Sensor driver
>> + * Copyright (c) 2014, Intel Corporation.
>> + *
>> + * This program is free software; you can redistribute it and/or modify it
>> + * under the terms and conditions of the GNU General Public License,
>> + * version 2, as published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope it will be useful, but WITHOUT
>> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
>> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
>> + * more details.
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/i2c.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/delay.h>
>> +#include <linux/slab.h>
>> +#include <linux/acpi.h>
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/pm.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +#include <linux/iio/buffer.h>
>> +#include <linux/iio/trigger.h>
>> +#include <linux/iio/events.h>
>> +#include <linux/iio/trigger_consumer.h>
>> +#include <linux/iio/triggered_buffer.h>
>> +
>> +#define BMG160_DRV_NAME		"bmg160"
>> +#define BMG160_IRQ_NAME		"bmg160_event"
>> +#define BMG160_GPIO_NAME		"gpio_int"
>> +
>> +#define BMG160_REG_CHIP_ID		0x00
>> +#define BMG160_CHIP_ID_VAL		0x0F
>> +
>> +#define BMG160_REG_PMU_LPW		0x11
>> +#define BMG160_MODE_NORMAL		0x00
>> +#define BMG160_MODE_DEEP_SUSPEND	0x20
>> +#define BMG160_MODE_SUSPEND		0x80
>> +
>> +#define BMG160_REG_RANGE		0x0F
>> +
>> +#define BMG160_RANGE_2000DPS		0
>> +#define BMG160_RANGE_1000DPS		1
>> +#define BMG160_RANGE_500DPS		2
>> +#define BMG160_RANGE_250DPS		3
>> +#define BMG160_RANGE_125DPS		4
>> +
>> +#define BMG160_REG_PMU_BW		0x10
>> +#define BMG160_NO_FILTER		0
>> +#define BMG160_DEF_BW			100
>> +
>> +#define BMG160_REG_INT_MAP_0		0x17
>> +#define BMG160_INT_MAP_0_BIT_ANY	BIT(1)
>> +
>> +#define BMG160_REG_INT_MAP_1		0x18
>> +#define BMG160_INT_MAP_1_BIT_NEW_DATA	BIT(0)
>> +
>> +#define BMG160_REG_INT_RST_LATCH	0x21
>> +#define BMG160_INT_MODE_LATCH_RESET	0x80
>> +#define BMG160_INT_MODE_LATCH_INT	0x0F
>> +#define BMG160_INT_MODE_NON_LATCH_INT	0x00
>> +
>> +#define BMG160_REG_INT_EN_0		0x15
>> +#define BMG160_DATA_ENABLE_INT		BIT(7)
>> +
>> +#define BMG160_REG_XOUT_L		0x02
>> +#define BMG160_AXIS_TO_REG(axis)	(BMG160_REG_XOUT_L + (axis * 2))
>> +
>> +#define BMG160_REG_SLOPE_THRES		0x1B
>> +#define BMG160_SLOPE_THRES_MASK	0x0F
>> +
>> +#define BMG160_REG_MOTION_INTR		0x1C
>> +#define BMG160_INT_MOTION_X		BIT(0)
>> +#define BMG160_INT_MOTION_Y		BIT(1)
>> +#define BMG160_INT_MOTION_Z		BIT(2)
>> +#define BMG160_ANY_DUR_MASK		0x30
>> +#define BMG160_ANY_DUR_SHIFT		4
>> +
>> +#define BMG160_REG_INT_STATUS_2	0x0B
>> +#define BMG160_ANY_MOTION_MASK		0x07
>> +
>> +#define BMG160_REG_TEMP		0x08
>> +#define BMG160_TEMP_CENTER_VAL		23
>> +
>> +#define BMG160_MAX_STARTUP_TIME_MS	80
>> +
>> +#define BMG160_AUTO_SUSPEND_DELAY_MS	2000
>> +
>> +struct bmg160_data {
>> +	struct i2c_client *client;
>> +	struct iio_trigger *dready_trig;
>> +	struct iio_trigger *motion_trig;
>> +	struct mutex mutex;
>> +	s16 buffer[8];
>> +	u8 bw_bits;
>> +	u32 dps_range;
>> +	int ev_enable_state;
>> +	int slope_thres;
>> +	bool dready_trigger_on;
>> +	bool motion_trigger_on;
>> +	int64_t timestamp;
>> +};
>> +
>> +enum bmg160_axis {
>> +	AXIS_X,
>> +	AXIS_Y,
>> +	AXIS_Z,
>> +};
>> +
>> +static const struct {
>> +	int val;
>> +	int bw_bits;
>> +} bmg160_samp_freq_table[] = { {100, 0x07},
>> +			       {200, 0x06},
>> +			       {400, 0x03},
>> +			       {1000, 0x02},
>> +			       {2000, 0x01} };
>> +
>> +static const struct {
>> +	int scale;
>> +	int dps_range;
>> +} bmg160_scale_table[] = { { 1065, BMG160_RANGE_2000DPS},
>> +			   { 532, BMG160_RANGE_1000DPS},
>> +			   { 266, BMG160_RANGE_500DPS},
>> +			   { 133, BMG160_RANGE_250DPS},
>> +			   { 66, BMG160_RANGE_125DPS} };
>> +
>> +static int bmg160_set_mode(struct bmg160_data *data, u8 mode)
>> +{
>> +	int ret;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_PMU_LPW, mode);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_pmu_lpw\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_convert_freq_to_bit(int val)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>> +		if (bmg160_samp_freq_table[i].val == val)
>> +			return bmg160_samp_freq_table[i].bw_bits;
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_set_bw(struct bmg160_data *data, int val)
>> +{
>> +	int ret;
>> +	int bw_bits;
>> +
>> +	bw_bits = bmg160_convert_freq_to_bit(val);
>> +	if (bw_bits < 0)
>> +		return bw_bits;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client, BMG160_REG_PMU_BW,
>> +					bw_bits);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_pmu_bw\n");
>> +		return ret;
>> +	}
>> +
>> +	data->bw_bits = bw_bits;
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_chip_init(struct bmg160_data *data)
>> +{
>> +	int ret;
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_CHIP_ID);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_chip_id\n");
>> +		return ret;
>> +	}
>> +
>> +	dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
>> +	if (ret != BMG160_CHIP_ID_VAL) {
>> +		dev_err(&data->client->dev, "invalid chip %x\n", ret);
>> +		return -ENODEV;
>> +	}
>> +
>> +	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* Wait upto 500 ms to be ready after changing mode */
>> +	usleep_range(500, 1000);
>> +
>> +	/* Set Bandwidth */
>> +	ret = bmg160_set_bw(data, BMG160_DEF_BW);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* Set Default Range */
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_RANGE,
>> +					BMG160_RANGE_500DPS);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_range\n");
>> +		return ret;
>> +	}
>> +	data->dps_range = BMG160_RANGE_500DPS;
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_SLOPE_THRES);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_slope_thres\n");
>> +		return ret;
>> +	}
>> +	data->slope_thres = ret;
>> +
>> +	/* Set default interrupt mode */
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_RST_LATCH,
>> +					BMG160_INT_MODE_LATCH_INT |
>> +					BMG160_INT_MODE_LATCH_RESET);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev,
>> +			"Error writing reg_motion_intr\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_set_power_state(struct bmg160_data *data, bool on)
>> +{
>> +	int ret;
>> +
>> +	if (on)
>> +		ret = pm_runtime_get_sync(&data->client->dev);
>> +	else {
>> +		pm_runtime_mark_last_busy(&data->client->dev);
>> +		ret = pm_runtime_put_autosuspend(&data->client->dev);
>> +	}
>> +
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev,
>> +			"Failed: bmg160_set_power_state for %d\n", on);
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_setup_any_motion_interrupt(struct bmg160_data *data,
>> +					     bool status)
>> +{
>> +	int ret;
>> +
>> +	/* Enable/Disable INT_MAP0 mapping */
>> +	ret = i2c_smbus_read_byte_data(data->client,  BMG160_REG_INT_MAP_0);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_int_map0\n");
>> +		return ret;
>> +	}
>> +	if (status)
>> +		ret |= BMG160_INT_MAP_0_BIT_ANY;
>> +	else
>> +		ret &= ~BMG160_INT_MAP_0_BIT_ANY;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_MAP_0,
>> +					ret);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_map0\n");
>> +		return ret;
>> +	}
>> +
>> +	/* Enable/Disable slope interrupts */
>> +	if (status) {
>> +		/* Update slope thres */
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_SLOPE_THRES,
>> +						data->slope_thres);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_slope_thres\n");
>> +			return ret;
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_MOTION_INTR,
>> +						BMG160_INT_MOTION_X |
>> +						BMG160_INT_MOTION_Y |
>> +						BMG160_INT_MOTION_Z);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_motion_intr\n");
>> +			return ret;
>> +		}
>> +
>> +		/*
>> +		 * New data interrupt is always non-latched,
>> +		 * which will have higher priority, so no need
>> +		 * to set latched mode, we will be flooded anyway with INTR
>> +		 */
>> +		if (!data->dready_trigger_on) {
>> +			ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_RST_LATCH,
>> +						BMG160_INT_MODE_LATCH_INT |
>> +						BMG160_INT_MODE_LATCH_RESET);
>> +			if (ret < 0) {
>> +				dev_err(&data->client->dev,
>> +					"Error writing reg_rst_latch\n");
>> +				return ret;
>> +			}
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						BMG160_DATA_ENABLE_INT);
>> +
>> +	} else
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						0);
>> +
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_setup_new_data_interrupt(struct bmg160_data *data,
>> +					   bool status)
>> +{
>> +	int ret;
>> +
>> +	/* Enable/Disable INT_MAP1 mapping */
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_MAP_1);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_int_map1\n");
>> +		return ret;
>> +	}
>> +
>> +	if (status)
>> +		ret |= BMG160_INT_MAP_1_BIT_NEW_DATA;
>> +	else
>> +		ret &= ~BMG160_INT_MAP_1_BIT_NEW_DATA;
>> +
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_MAP_1,
>> +					ret);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_map1\n");
>> +		return ret;
>> +	}
>> +
>> +	if (status) {
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_RST_LATCH,
>> +						BMG160_INT_MODE_NON_LATCH_INT |
>> +						BMG160_INT_MODE_LATCH_RESET);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_rst_latch\n");
>> +				return ret;
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						BMG160_DATA_ENABLE_INT);
>> +
>> +	} else {
>> +		/* Restore interrupt mode */
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_RST_LATCH,
>> +						BMG160_INT_MODE_LATCH_INT |
>> +						BMG160_INT_MODE_LATCH_RESET);
>> +		if (ret < 0) {
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_rst_latch\n");
>> +				return ret;
>> +		}
>> +
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +						BMG160_REG_INT_EN_0,
>> +						0);
>> +	}
>> +
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_get_bw(struct bmg160_data *data, int *val)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>> +		if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
>> +			*val = bmg160_samp_freq_table[i].val;
>> +			return IIO_VAL_INT;
>> +		}
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_set_scale(struct bmg160_data *data, int val)
>> +{
>> +	int ret, i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>> +		if (bmg160_scale_table[i].scale == val) {
>> +			ret = i2c_smbus_write_byte_data(
>> +					data->client,
>> +					BMG160_REG_RANGE,
>> +					bmg160_scale_table[i].dps_range);
>> +			if (ret < 0) {
>> +				dev_err(&data->client->dev,
>> +					"Error writing reg_range\n");
>> +				return ret;
>> +			}
>> +			data->dps_range = bmg160_scale_table[i].dps_range;
>> +			return 0;
>> +		}
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_get_temp(struct bmg160_data *data, int *val)
>> +{
>> +	int ret;
>> +
>> +	mutex_lock(&data->mutex);
>> +	ret = bmg160_set_power_state(data, true);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_TEMP);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_temp\n");
>> +		bmg160_set_power_state(data, false);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	*val = sign_extend32(ret, 7);
>> +	ret = bmg160_set_power_state(data, false);
>> +	mutex_unlock(&data->mutex);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	return IIO_VAL_INT;
>> +}
>> +
>> +static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
>> +{
>> +	int ret;
>> +
>> +	mutex_lock(&data->mutex);
>> +	ret = bmg160_set_power_state(data, true);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	ret = i2c_smbus_read_word_data(data->client, BMG160_AXIS_TO_REG(axis));
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading axis %d\n", axis);
>> +		bmg160_set_power_state(data, false);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	*val = sign_extend32(ret, 15);
>> +	ret = bmg160_set_power_state(data, false);
>> +	mutex_unlock(&data->mutex);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	return IIO_VAL_INT;
>> +}
>> +
>> +static int bmg160_read_raw(struct iio_dev *indio_dev,
>> +			   struct iio_chan_spec const *chan,
>> +			   int *val, int *val2, long mask)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_RAW:
>> +		switch (chan->type) {
>> +		case IIO_TEMP:
>> +			return bmg160_get_temp(data, val);
>> +		case IIO_ANGL_VEL:
>> +			if (iio_buffer_enabled(indio_dev))
>> +				return -EBUSY;
>> +			else
>> +				return bmg160_get_axis(data, chan->scan_index,
>> +						       val);
>> +		default:
>> +			return -EINVAL;
>> +		}
>> +	case IIO_CHAN_INFO_OFFSET:
>> +		if (chan->type == IIO_TEMP) {
>> +			*val = BMG160_TEMP_CENTER_VAL;
>> +			return IIO_VAL_INT;
>> +		} else
>> +			return -EINVAL;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		*val = 0;
>> +		switch (chan->type) {
>> +		case IIO_TEMP:
>> +			*val2 = 500000;
>> +			return IIO_VAL_INT_PLUS_MICRO;
>> +		case IIO_ANGL_VEL:
>> +		{
>> +			int i;
>> +
>> +			for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>> +				if (bmg160_scale_table[i].dps_range ==
>> +							data->dps_range) {
>> +					*val2 = bmg160_scale_table[i].scale;
>> +					return IIO_VAL_INT_PLUS_MICRO;
>> +				}
>> +			}
>> +			return -EINVAL;
>> +		}
>> +		default:
>> +			return -EINVAL;
>> +		}
>> +	case IIO_CHAN_INFO_SAMP_FREQ:
>> +		*val2 = 0;
>> +		mutex_lock(&data->mutex);
>> +		ret = bmg160_get_bw(data, val);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +}
>> +
>> +static int bmg160_write_raw(struct iio_dev *indio_dev,
>> +			    struct iio_chan_spec const *chan,
>> +			    int val, int val2, long mask)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_SAMP_FREQ:
>> +		mutex_lock(&data->mutex);
>> +		/*
>> +		 * Section 4.2 of spec
>> +		 * In suspend mode, the only supported operations are reading
>> +		 * registers as well as writing to the (0x14) softreset
>> +		 * register. Since we will be in suspend mode by default, change
>> +		 * mode to power on for other writes.
>> +		 */
>> +		ret = bmg160_set_power_state(data, true);
>> +		if (ret < 0) {
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_bw(data, val);
>> +		if (ret < 0) {
>> +			bmg160_set_power_state(data, false);
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_power_state(data, false);
> Could this end up disabling the part when in triggered mode?
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		if (val)
>> +			return -EINVAL;
>> +
>> +		mutex_lock(&data->mutex);
>> +		/* Refer to comments above for the suspend mode ops */
>> +		ret = bmg160_set_power_state(data, true);
>> +		if (ret < 0) {
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_scale(data, val2);
>> +		if (ret < 0) {
>> +			bmg160_set_power_state(data, false);
>> +			mutex_unlock(&data->mutex);
>> +			return ret;
>> +		}
>> +		ret = bmg160_set_power_state(data, false);
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int bmg160_read_event(struct iio_dev *indio_dev,
>> +			     const struct iio_chan_spec *chan,
>> +			     enum iio_event_type type,
>> +			     enum iio_event_direction dir,
>> +			     enum iio_event_info info,
>> +			     int *val, int *val2)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	*val2 = 0;
>> +	switch (info) {
>> +	case IIO_EV_INFO_VALUE:
>> +		*val = data->slope_thres & BMG160_SLOPE_THRES_MASK;
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return IIO_VAL_INT;
>> +}
>> +
>> +static int bmg160_write_event(struct iio_dev *indio_dev,
>> +			      const struct iio_chan_spec *chan,
>> +			      enum iio_event_type type,
>> +			      enum iio_event_direction dir,
>> +			      enum iio_event_info info,
>> +			      int val, int val2)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	switch (info) {
>> +	case IIO_EV_INFO_VALUE:
>> +		if (data->ev_enable_state)
>> +			return -EBUSY;
>> +		data->slope_thres &= ~BMG160_SLOPE_THRES_MASK;
>> +		data->slope_thres |= (val & BMG160_SLOPE_THRES_MASK);
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_read_event_config(struct iio_dev *indio_dev,
>> +				    const struct iio_chan_spec *chan,
>> +				    enum iio_event_type type,
>> +				    enum iio_event_direction dir)
>> +{
>> +
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	return data->ev_enable_state;
>> +}
>> +
>> +static int bmg160_write_event_config(struct iio_dev *indio_dev,
>> +				     const struct iio_chan_spec *chan,
>> +				     enum iio_event_type type,
>> +				     enum iio_event_direction dir,
>> +				     int state)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	if (state && data->ev_enable_state)
>> +		return 0;
>> +
>> +	mutex_lock(&data->mutex);
>> +
>> +	if (!state && data->motion_trigger_on) {
>> +		data->ev_enable_state = 0;
>> +		mutex_unlock(&data->mutex);
>> +		return 0;
>> +	}
>> +	/*
>> +	 * We will expect the enable and disable to do operation in
>> +	 * in reverse order. This will happen here anyway as our
>> +	 * resume operation uses sync mode runtime pm calls, the
>> +	 * suspend operation will be delayed by autosuspend delay
>> +	 * So the disable operation will still happen in reverse of
>> +	 * enable operation. When runtime pm is disabled the mode
>> +	 * is always on so sequence doesn't matter
>> +	 */
> Thanks for the detailed comment!
>> +	ret = bmg160_set_power_state(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	ret =  bmg160_setup_any_motion_interrupt(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +
>> +	data->ev_enable_state = state;
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_validate_trigger(struct iio_dev *indio_dev,
>> +				   struct iio_trigger *trig)
>> +{
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	if (data->dready_trig != trig && data->motion_trig != trig)
>> +		return -EINVAL;
>> +
>> +	return 0;
>> +}
>> +
>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 400 1000 2000");
>> +
>> +static IIO_CONST_ATTR(in_anglvel_scale_available,
>> +		      "0.001065 0.000532 0.000266 0.000133 0.000066");
>> +
>> +static struct attribute *bmg160_attributes[] = {
>> +	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
>> +	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
>> +	NULL,
>> +};
>> +
>> +static const struct attribute_group bmg160_attrs_group = {
>> +	.attrs = bmg160_attributes,
>> +};
>> +
>> +static const struct iio_event_spec bmg160_event = {
>> +		.type = IIO_EV_TYPE_ROC,
>> +		.dir = IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING,
>> +		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
>> +				       BIT(IIO_EV_INFO_ENABLE)
>> +};
>> +
>> +#define BMG160_CHANNEL(_axis) {					\
>> +	.type = IIO_ANGL_VEL,						\
>> +	.modified = 1,							\
>> +	.channel2 = IIO_MOD_##_axis,					\
>> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
>> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
>> +				    BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
>> +	.scan_index = AXIS_##_axis,					\
>> +	.scan_type = {							\
>> +		.sign = 's',						\
>> +		.realbits = 16,					\
>> +		.storagebits = 16,					\
>> +	},								\
>> +	.event_spec = &bmg160_event,					\
>> +	.num_event_specs = 1						\
>> +}
>> +
>> +static const struct iio_chan_spec bmg160_channels[] = {
>> +	{
>> +		.type = IIO_TEMP,
>> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> +				      BIT(IIO_CHAN_INFO_SCALE) |
>> +				      BIT(IIO_CHAN_INFO_OFFSET),
>> +		.scan_index = -1,
>> +	},
>> +	BMG160_CHANNEL(X),
>> +	BMG160_CHANNEL(Y),
>> +	BMG160_CHANNEL(Z),
>> +	IIO_CHAN_SOFT_TIMESTAMP(3),
>> +};
>> +
>> +static const struct iio_info bmg160_info = {
>> +	.attrs			= &bmg160_attrs_group,
>> +	.read_raw		= bmg160_read_raw,
>> +	.write_raw		= bmg160_write_raw,
>> +	.read_event_value	= bmg160_read_event,
>> +	.write_event_value	= bmg160_write_event,
>> +	.write_event_config	= bmg160_write_event_config,
>> +	.read_event_config	= bmg160_read_event_config,
>> +	.validate_trigger	= bmg160_validate_trigger,
>> +	.driver_module		= THIS_MODULE,
>> +};
>> +
>> +static irqreturn_t bmg160_trigger_handler(int irq, void *p)
>> +{
>> +	struct iio_poll_func *pf = p;
>> +	struct iio_dev *indio_dev = pf->indio_dev;
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int bit, ret, i = 0;
>> +
>> +	mutex_lock(&data->mutex);
>> +	for_each_set_bit(bit, indio_dev->buffer->scan_mask,
>> +			 indio_dev->masklength) {
>> +		ret = i2c_smbus_read_word_data(data->client,
>> +					       BMG160_AXIS_TO_REG(bit));
>> +		if (ret < 0) {
>> +			mutex_unlock(&data->mutex);
>> +			goto err;
>> +		}
>> +		data->buffer[i++] = ret;
>> +	}
>> +	mutex_unlock(&data->mutex);
>> +
>> +	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
>> +					   data->timestamp);
>> +err:
>> +	iio_trigger_notify_done(indio_dev->trig);
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int bmg160_trig_try_reen(struct iio_trigger *trig)
>> +{
>> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	/* new data interrupts don't need ack */
>> +	if (data->dready_trigger_on)
>> +		return 0;
>> +
>> +	/* Set latched mode interrupt and clear any latched interrupt */
>> +	ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_RST_LATCH,
>> +					BMG160_INT_MODE_LATCH_INT |
>> +					BMG160_INT_MODE_LATCH_RESET);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_data_rdy_trigger_set_state(struct iio_trigger *trig,
>> +					     bool state)
>> +{
>> +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	mutex_lock(&data->mutex);
>> +
>> +	if (!state && data->ev_enable_state && data->motion_trigger_on) {
>> +		data->motion_trigger_on = false;
>> +		mutex_unlock(&data->mutex);
>> +		return 0;
>> +	}
>> +
>> +	/*
>> +	 * Refer to comment in bmg160_write_event_config for
>> +	 * enable/disable operation order
>> +	 */
>> +	ret = bmg160_set_power_state(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +	if (data->motion_trig == trig)
>> +		ret =  bmg160_setup_any_motion_interrupt(data, state);
>> +	else
>> +		ret = bmg160_setup_new_data_interrupt(data, state);
>> +	if (ret < 0) {
>> +		mutex_unlock(&data->mutex);
>> +		return ret;
>> +	}
>> +	if (data->motion_trig == trig)
>> +		data->motion_trigger_on = state;
>> +	else
>> +		data->dready_trigger_on = state;
>> +
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct iio_trigger_ops bmg160_trigger_ops = {
>> +	.set_trigger_state = bmg160_data_rdy_trigger_set_state,
>> +	.try_reenable = bmg160_trig_try_reen,
>> +	.owner = THIS_MODULE,
>> +};
>> +
>> +static irqreturn_t bmg160_event_handler(int irq, void *private)
>> +{
>> +	struct iio_dev *indio_dev = private;
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +	int dir;
>> +
>> +	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_STATUS_2);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "Error reading reg_int_status2\n");
>> +		goto ack_intr_status;
>> +	}
>> +
>> +	if (ret & 0x08)
>> +		dir = IIO_EV_DIR_RISING;
>> +	else
>> +		dir = IIO_EV_DIR_FALLING;
>> +
>> +	if (ret & BMG160_ANY_MOTION_MASK)
>> +		iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
>> +							0,
>> +							IIO_MOD_X_OR_Y_OR_Z,
>> +							IIO_EV_TYPE_ROC,
>> +							dir),
>> +							data->timestamp);
>> +
>> +ack_intr_status:
>> +	if (!data->dready_trigger_on) {
>> +		ret = i2c_smbus_write_byte_data(data->client,
>> +					BMG160_REG_INT_RST_LATCH,
>> +					BMG160_INT_MODE_LATCH_INT |
>> +					BMG160_INT_MODE_LATCH_RESET);
>> +		if (ret < 0)
>> +			dev_err(&data->client->dev,
>> +				"Error writing reg_rst_latch\n");
>> +	}
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static irqreturn_t bmg160_data_rdy_trig_poll(int irq, void *private)
>> +{
>> +	struct iio_dev *indio_dev = private;
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	data->timestamp = iio_get_time_ns();
>> +
>> +	if (data->dready_trigger_on)
>> +		iio_trigger_poll(data->dready_trig);
>> +	else if (data->motion_trigger_on)
>> +		iio_trigger_poll(data->motion_trig);
>> +
>> +	if (data->ev_enable_state)
>> +		return IRQ_WAKE_THREAD;
>> +	else
>> +		return IRQ_HANDLED;
>> +
>> +}
>> +
>> +static int bmg160_acpi_gpio_probe(struct i2c_client *client,
>> +				  struct bmg160_data *data)
>> +{
>> +	const struct acpi_device_id *id;
>> +	struct device *dev;
>> +	struct gpio_desc *gpio;
>> +	int ret;
>> +
>> +	if (!client)
>> +		return -EINVAL;
>> +
>> +	dev = &client->dev;
>> +	if (!ACPI_HANDLE(dev))
>> +		return -ENODEV;
>> +
>> +	id = acpi_match_device(dev->driver->acpi_match_table, dev);
>> +	if (!id)
>> +		return -ENODEV;
>> +
>> +	/* data ready gpio interrupt pin */
>> +	gpio = devm_gpiod_get_index(dev, BMG160_GPIO_NAME, 0);
>> +	if (IS_ERR(gpio)) {
>> +		dev_err(dev, "acpi gpio get index failed\n");
>> +		return PTR_ERR(gpio);
>> +	}
>> +
>> +	ret = gpiod_direction_input(gpio);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = gpiod_to_irq(gpio);
>> +
>> +	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
>> +
>> +	return ret;
>> +}
>> +
>> +static int bmg160_probe(struct i2c_client *client,
>> +			const struct i2c_device_id *id)
>> +{
>> +	struct bmg160_data *data;
>> +	struct iio_dev *indio_dev;
>> +	int ret;
>> +
>> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>> +	if (!indio_dev)
>> +		return -ENOMEM;
>> +
>> +	data = iio_priv(indio_dev);
>> +	i2c_set_clientdata(client, indio_dev);
>> +	data->client = client;
>> +
>> +	ret = bmg160_chip_init(data);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	mutex_init(&data->mutex);
>> +
>> +	indio_dev->dev.parent = &client->dev;
>> +	indio_dev->channels = bmg160_channels;
>> +	indio_dev->num_channels = ARRAY_SIZE(bmg160_channels);
>> +	indio_dev->name = BMG160_DRV_NAME;
>> +	indio_dev->modes = INDIO_DIRECT_MODE;
>> +	indio_dev->info = &bmg160_info;
>> +
>> +	if (client->irq <= 0)
>> +		client->irq = bmg160_acpi_gpio_probe(client, data);
>> +
>> +	if (client->irq > 0) {
>> +		ret = devm_request_threaded_irq(&client->dev,
>> +						client->irq,
>> +						bmg160_data_rdy_trig_poll,
>> +						bmg160_event_handler,
>> +						IRQF_TRIGGER_RISING,
>> +						BMG160_IRQ_NAME,
>> +						indio_dev);
>> +		if (ret)
>> +			return ret;
>> +
>> +		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
>> +							   "%s-dev%d",
>> +							   indio_dev->name,
>> +							   indio_dev->id);
>> +		if (!data->dready_trig)
>> +			return -ENOMEM;
>> +
>> +		data->motion_trig = devm_iio_trigger_alloc(&client->dev,
>> +							  "%s-any-motion-dev%d",
>> +							  indio_dev->name,
>> +							  indio_dev->id);
>> +		if (!data->motion_trig)
>> +			return -ENOMEM;
>> +
>> +		data->dready_trig->dev.parent = &client->dev;
>> +		data->dready_trig->ops = &bmg160_trigger_ops;
>> +		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
>> +		ret = iio_trigger_register(data->dready_trig);
>> +		if (ret)
>> +			return ret;
>> +
>> +		data->motion_trig->dev.parent = &client->dev;
>> +		data->motion_trig->ops = &bmg160_trigger_ops;
>> +		iio_trigger_set_drvdata(data->motion_trig, indio_dev);
>> +		ret = iio_trigger_register(data->motion_trig);
>> +		if (ret) {
>> +			data->motion_trig = NULL;
>> +			goto err_trigger_unregister;
>> +		}
>> +
>> +		ret = iio_triggered_buffer_setup(indio_dev,
>> +						 NULL,
>> +						 bmg160_trigger_handler,
>> +						 NULL);
>> +		if (ret < 0) {
>> +			dev_err(&client->dev,
>> +				"iio triggered buffer setup failed\n");
>> +			goto err_trigger_unregister;
>> +		}
>> +	}
>> +
>> +	ret = iio_device_register(indio_dev);
>> +	if (ret < 0) {
>> +		dev_err(&client->dev, "unable to register iio device\n");
>> +		goto err_buffer_cleanup;
>> +	}
>> +
>> +	ret = pm_runtime_set_active(&client->dev);
>> +	if (ret)
>> +		goto err_iio_unregister;
>> +
>> +	pm_runtime_enable(&client->dev);
>> +	pm_runtime_set_autosuspend_delay(&client->dev,
>> +					 BMG160_AUTO_SUSPEND_DELAY_MS);
>> +	pm_runtime_use_autosuspend(&client->dev);
>> +
>> +	return 0;
>> +
>> +err_iio_unregister:
>> +	iio_device_unregister(indio_dev);
>> +err_buffer_cleanup:
>> +	if (data->dready_trig)
>> +		iio_triggered_buffer_cleanup(indio_dev);
>> +err_trigger_unregister:
>> +	if (data->dready_trig)
>> +		iio_trigger_unregister(data->dready_trig);
>> +	if (data->motion_trig)
>> +		iio_trigger_unregister(data->motion_trig);
>> +
>> +	return ret;
>> +}
>> +
>> +static int bmg160_remove(struct i2c_client *client)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	pm_runtime_disable(&client->dev);
>> +	pm_runtime_set_suspended(&client->dev);
>> +	pm_runtime_put_noidle(&client->dev);
>> +
>> +	iio_device_unregister(indio_dev);
>> +
>> +	if (data->dready_trig) {
>> +		iio_triggered_buffer_cleanup(indio_dev);
>> +		iio_trigger_unregister(data->dready_trig);
>> +		iio_trigger_unregister(data->motion_trig);
>> +	}
>> +
>> +	mutex_lock(&data->mutex);
>> +	bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +#ifdef CONFIG_PM_SLEEP
>> +static int bmg160_suspend(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	mutex_lock(&data->mutex);
>> +	bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +
>> +static int bmg160_resume(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	mutex_lock(&data->mutex);
>> +	if (data->dready_trigger_on || data->motion_trigger_on ||
>> +							data->ev_enable_state)
>> +		bmg160_set_mode(data, BMG160_MODE_NORMAL);
>> +	mutex_unlock(&data->mutex);
>> +
>> +	return 0;
>> +}
>> +#endif
>> +
>> +#ifdef CONFIG_PM_RUNTIME
>> +static int bmg160_runtime_suspend(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +
>> +	return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>> +}
>> +
>> +static int bmg160_runtime_resume(struct device *dev)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>> +	struct bmg160_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
>> +
>> +	return 0;
>> +}
>> +#endif
>> +
>> +static const struct dev_pm_ops bmg160_pm_ops = {
>> +	SET_SYSTEM_SLEEP_PM_OPS(bmg160_suspend, bmg160_resume)
>> +	SET_RUNTIME_PM_OPS(bmg160_runtime_suspend,
>> +			   bmg160_runtime_resume, NULL)
>> +};
>> +
>> +static const struct acpi_device_id bmg160_acpi_match[] = {
>> +	{"BMG0160", 0},
>> +	{ },
>> +};
>> +MODULE_DEVICE_TABLE(acpi, bmg160_acpi_match);
>> +
>> +static const struct i2c_device_id bmg160_id[] = {
>> +	{"bmg160", 0},
>> +	{}
>> +};
>> +
>> +MODULE_DEVICE_TABLE(i2c, bmg160_id);
>> +
>> +static struct i2c_driver bmg160_driver = {
>> +	.driver = {
>> +		.name	= BMG160_DRV_NAME,
>> +		.acpi_match_table = ACPI_PTR(bmg160_acpi_match),
>> +		.pm	= &bmg160_pm_ops,
>> +	},
>> +	.probe		= bmg160_probe,
>> +	.remove		= bmg160_remove,
>> +	.id_table	= bmg160_id,
>> +};
>> +module_i2c_driver(bmg160_driver);
>> +
>> +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_DESCRIPTION("BMG160 Gyro driver");
>>
>

Re: [PATCH v3 1/2] iio:gyro:bmg160 Gyro Sensor driver

[Jonathan Cameron]

On 12/08/14 20:06, Srinivas Pandruvada wrote:
> On 08/07/2014 03:39 AM, Jonathan Cameron wrote:
>> On 05/08/14 22:57, Srinivas Pandruvada wrote:
>>> This change implements support for BMG160 Gyro sensor. Although chip
>>> has several advanced features, this change implements minimum set
>>> required for using gyro sensor.
>>>
>>> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
>> One more query.  In the write_raw function you always enable then suspend the
>> device.  The enable is safe, but if you have a write to the attributes
>> whilst operating in triggered / buffered mode will it not disable the
>> device?  It is perfectly permissible to ignore such a write (return -EBUSY)
>> but I don't think you are doing so.
>>
> 
> I tested this. When trigger/events are active then first call to bmg160_set_power_state will increment runtime pm
> refcount and also execute runtime resume to change the mode to NORMAL.
> But when write_raw is called while the trigger/events are active the runtime PM refcount is incremented since it was
> already more than 0, so the resume is not actually called. When at the end of write_raw bmg160_set_power_state to turn
> off, the ref count is simply decremented, but since it is not zero, runtime suspend will not be called.
> 
Sorry, managed to loose this driver so will pick it up after Greg
has taken the pull request I'm just sending.

Not exactly a lack of time at this point in the cycle ;)

> Thanks,
> Srinivas
> 
>> Otherwise, looks good to me.  Nice explanatory comments as well!
>>> ---
>>>   drivers/iio/gyro/Kconfig  |   11 +
>>>   drivers/iio/gyro/Makefile |    1 +
>>>   drivers/iio/gyro/bmg160.c | 1211 +++++++++++++++++++++++++++++++++++++++++++++
>>>   3 files changed, 1223 insertions(+)
>>>   create mode 100644 drivers/iio/gyro/bmg160.c
>>>
>>> diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
>>> index ac2d69e..d630ae9 100644
>>> --- a/drivers/iio/gyro/Kconfig
>>> +++ b/drivers/iio/gyro/Kconfig
>>> @@ -50,6 +50,17 @@ config ADXRS450
>>>         This driver can also be built as a module.  If so, the module
>>>         will be called adxrs450.
>>>
>>> +config BMG160
>>> +    tristate "BOSCH BMG160 Gyro Sensor"
>>> +    depends on I2C
>>> +    select IIO_TRIGGERED_BUFFER if IIO_BUFFER
>>> +    help
>>> +      Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
>>> +      driver.
>>> +
>>> +      This driver can also be built as a module.  If so, the module
>>> +      will be called bmg160.
>>> +
>>>   config HID_SENSOR_GYRO_3D
>>>       depends on HID_SENSOR_HUB
>>>       select IIO_BUFFER
>>> diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
>>> index 2f2752a..36a3877 100644
>>> --- a/drivers/iio/gyro/Makefile
>>> +++ b/drivers/iio/gyro/Makefile
>>> @@ -8,6 +8,7 @@ obj-$(CONFIG_ADIS16130) += adis16130.o
>>>   obj-$(CONFIG_ADIS16136) += adis16136.o
>>>   obj-$(CONFIG_ADIS16260) += adis16260.o
>>>   obj-$(CONFIG_ADXRS450) += adxrs450.o
>>> +obj-$(CONFIG_BMG160) += bmg160.o
>>>
>>>   obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
>>>
>>> diff --git a/drivers/iio/gyro/bmg160.c b/drivers/iio/gyro/bmg160.c
>>> new file mode 100644
>>> index 0000000..80f92a6
>>> --- /dev/null
>>> +++ b/drivers/iio/gyro/bmg160.c
>>> @@ -0,0 +1,1211 @@
>>> +/*
>>> + * BMG160 Gyro Sensor driver
>>> + * Copyright (c) 2014, Intel Corporation.
>>> + *
>>> + * This program is free software; you can redistribute it and/or modify it
>>> + * under the terms and conditions of the GNU General Public License,
>>> + * version 2, as published by the Free Software Foundation.
>>> + *
>>> + * This program is distributed in the hope it will be useful, but WITHOUT
>>> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
>>> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
>>> + * more details.
>>> + */
>>> +
>>> +#include <linux/module.h>
>>> +#include <linux/i2c.h>
>>> +#include <linux/interrupt.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/slab.h>
>>> +#include <linux/acpi.h>
>>> +#include <linux/gpio/consumer.h>
>>> +#include <linux/pm.h>
>>> +#include <linux/pm_runtime.h>
>>> +#include <linux/iio/iio.h>
>>> +#include <linux/iio/sysfs.h>
>>> +#include <linux/iio/buffer.h>
>>> +#include <linux/iio/trigger.h>
>>> +#include <linux/iio/events.h>
>>> +#include <linux/iio/trigger_consumer.h>
>>> +#include <linux/iio/triggered_buffer.h>
>>> +
>>> +#define BMG160_DRV_NAME        "bmg160"
>>> +#define BMG160_IRQ_NAME        "bmg160_event"
>>> +#define BMG160_GPIO_NAME        "gpio_int"
>>> +
>>> +#define BMG160_REG_CHIP_ID        0x00
>>> +#define BMG160_CHIP_ID_VAL        0x0F
>>> +
>>> +#define BMG160_REG_PMU_LPW        0x11
>>> +#define BMG160_MODE_NORMAL        0x00
>>> +#define BMG160_MODE_DEEP_SUSPEND    0x20
>>> +#define BMG160_MODE_SUSPEND        0x80
>>> +
>>> +#define BMG160_REG_RANGE        0x0F
>>> +
>>> +#define BMG160_RANGE_2000DPS        0
>>> +#define BMG160_RANGE_1000DPS        1
>>> +#define BMG160_RANGE_500DPS        2
>>> +#define BMG160_RANGE_250DPS        3
>>> +#define BMG160_RANGE_125DPS        4
>>> +
>>> +#define BMG160_REG_PMU_BW        0x10
>>> +#define BMG160_NO_FILTER        0
>>> +#define BMG160_DEF_BW            100
>>> +
>>> +#define BMG160_REG_INT_MAP_0        0x17
>>> +#define BMG160_INT_MAP_0_BIT_ANY    BIT(1)
>>> +
>>> +#define BMG160_REG_INT_MAP_1        0x18
>>> +#define BMG160_INT_MAP_1_BIT_NEW_DATA    BIT(0)
>>> +
>>> +#define BMG160_REG_INT_RST_LATCH    0x21
>>> +#define BMG160_INT_MODE_LATCH_RESET    0x80
>>> +#define BMG160_INT_MODE_LATCH_INT    0x0F
>>> +#define BMG160_INT_MODE_NON_LATCH_INT    0x00
>>> +
>>> +#define BMG160_REG_INT_EN_0        0x15
>>> +#define BMG160_DATA_ENABLE_INT        BIT(7)
>>> +
>>> +#define BMG160_REG_XOUT_L        0x02
>>> +#define BMG160_AXIS_TO_REG(axis)    (BMG160_REG_XOUT_L + (axis * 2))
>>> +
>>> +#define BMG160_REG_SLOPE_THRES        0x1B
>>> +#define BMG160_SLOPE_THRES_MASK    0x0F
>>> +
>>> +#define BMG160_REG_MOTION_INTR        0x1C
>>> +#define BMG160_INT_MOTION_X        BIT(0)
>>> +#define BMG160_INT_MOTION_Y        BIT(1)
>>> +#define BMG160_INT_MOTION_Z        BIT(2)
>>> +#define BMG160_ANY_DUR_MASK        0x30
>>> +#define BMG160_ANY_DUR_SHIFT        4
>>> +
>>> +#define BMG160_REG_INT_STATUS_2    0x0B
>>> +#define BMG160_ANY_MOTION_MASK        0x07
>>> +
>>> +#define BMG160_REG_TEMP        0x08
>>> +#define BMG160_TEMP_CENTER_VAL        23
>>> +
>>> +#define BMG160_MAX_STARTUP_TIME_MS    80
>>> +
>>> +#define BMG160_AUTO_SUSPEND_DELAY_MS    2000
>>> +
>>> +struct bmg160_data {
>>> +    struct i2c_client *client;
>>> +    struct iio_trigger *dready_trig;
>>> +    struct iio_trigger *motion_trig;
>>> +    struct mutex mutex;
>>> +    s16 buffer[8];
>>> +    u8 bw_bits;
>>> +    u32 dps_range;
>>> +    int ev_enable_state;
>>> +    int slope_thres;
>>> +    bool dready_trigger_on;
>>> +    bool motion_trigger_on;
>>> +    int64_t timestamp;
>>> +};
>>> +
>>> +enum bmg160_axis {
>>> +    AXIS_X,
>>> +    AXIS_Y,
>>> +    AXIS_Z,
>>> +};
>>> +
>>> +static const struct {
>>> +    int val;
>>> +    int bw_bits;
>>> +} bmg160_samp_freq_table[] = { {100, 0x07},
>>> +                   {200, 0x06},
>>> +                   {400, 0x03},
>>> +                   {1000, 0x02},
>>> +                   {2000, 0x01} };
>>> +
>>> +static const struct {
>>> +    int scale;
>>> +    int dps_range;
>>> +} bmg160_scale_table[] = { { 1065, BMG160_RANGE_2000DPS},
>>> +               { 532, BMG160_RANGE_1000DPS},
>>> +               { 266, BMG160_RANGE_500DPS},
>>> +               { 133, BMG160_RANGE_250DPS},
>>> +               { 66, BMG160_RANGE_125DPS} };
>>> +
>>> +static int bmg160_set_mode(struct bmg160_data *data, u8 mode)
>>> +{
>>> +    int ret;
>>> +
>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>> +                    BMG160_REG_PMU_LPW, mode);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_pmu_lpw\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_convert_freq_to_bit(int val)
>>> +{
>>> +    int i;
>>> +
>>> +    for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>>> +        if (bmg160_samp_freq_table[i].val == val)
>>> +            return bmg160_samp_freq_table[i].bw_bits;
>>> +    }
>>> +
>>> +    return -EINVAL;
>>> +}
>>> +
>>> +static int bmg160_set_bw(struct bmg160_data *data, int val)
>>> +{
>>> +    int ret;
>>> +    int bw_bits;
>>> +
>>> +    bw_bits = bmg160_convert_freq_to_bit(val);
>>> +    if (bw_bits < 0)
>>> +        return bw_bits;
>>> +
>>> +    ret = i2c_smbus_write_byte_data(data->client, BMG160_REG_PMU_BW,
>>> +                    bw_bits);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_pmu_bw\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    data->bw_bits = bw_bits;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_chip_init(struct bmg160_data *data)
>>> +{
>>> +    int ret;
>>> +
>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_CHIP_ID);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error reading reg_chip_id\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
>>> +    if (ret != BMG160_CHIP_ID_VAL) {
>>> +        dev_err(&data->client->dev, "invalid chip %x\n", ret);
>>> +        return -ENODEV;
>>> +    }
>>> +
>>> +    ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    /* Wait upto 500 ms to be ready after changing mode */
>>> +    usleep_range(500, 1000);
>>> +
>>> +    /* Set Bandwidth */
>>> +    ret = bmg160_set_bw(data, BMG160_DEF_BW);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    /* Set Default Range */
>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>> +                    BMG160_REG_RANGE,
>>> +                    BMG160_RANGE_500DPS);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_range\n");
>>> +        return ret;
>>> +    }
>>> +    data->dps_range = BMG160_RANGE_500DPS;
>>> +
>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_SLOPE_THRES);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error reading reg_slope_thres\n");
>>> +        return ret;
>>> +    }
>>> +    data->slope_thres = ret;
>>> +
>>> +    /* Set default interrupt mode */
>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>> +                    BMG160_REG_INT_RST_LATCH,
>>> +                    BMG160_INT_MODE_LATCH_INT |
>>> +                    BMG160_INT_MODE_LATCH_RESET);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev,
>>> +            "Error writing reg_motion_intr\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_set_power_state(struct bmg160_data *data, bool on)
>>> +{
>>> +    int ret;
>>> +
>>> +    if (on)
>>> +        ret = pm_runtime_get_sync(&data->client->dev);
>>> +    else {
>>> +        pm_runtime_mark_last_busy(&data->client->dev);
>>> +        ret = pm_runtime_put_autosuspend(&data->client->dev);
>>> +    }
>>> +
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev,
>>> +            "Failed: bmg160_set_power_state for %d\n", on);
>>> +        return ret;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_setup_any_motion_interrupt(struct bmg160_data *data,
>>> +                         bool status)
>>> +{
>>> +    int ret;
>>> +
>>> +    /* Enable/Disable INT_MAP0 mapping */
>>> +    ret = i2c_smbus_read_byte_data(data->client,  BMG160_REG_INT_MAP_0);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error reading reg_int_map0\n");
>>> +        return ret;
>>> +    }
>>> +    if (status)
>>> +        ret |= BMG160_INT_MAP_0_BIT_ANY;
>>> +    else
>>> +        ret &= ~BMG160_INT_MAP_0_BIT_ANY;
>>> +
>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>> +                    BMG160_REG_INT_MAP_0,
>>> +                    ret);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_int_map0\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    /* Enable/Disable slope interrupts */
>>> +    if (status) {
>>> +        /* Update slope thres */
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_SLOPE_THRES,
>>> +                        data->slope_thres);
>>> +        if (ret < 0) {
>>> +            dev_err(&data->client->dev,
>>> +                "Error writing reg_slope_thres\n");
>>> +            return ret;
>>> +        }
>>> +
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_MOTION_INTR,
>>> +                        BMG160_INT_MOTION_X |
>>> +                        BMG160_INT_MOTION_Y |
>>> +                        BMG160_INT_MOTION_Z);
>>> +        if (ret < 0) {
>>> +            dev_err(&data->client->dev,
>>> +                "Error writing reg_motion_intr\n");
>>> +            return ret;
>>> +        }
>>> +
>>> +        /*
>>> +         * New data interrupt is always non-latched,
>>> +         * which will have higher priority, so no need
>>> +         * to set latched mode, we will be flooded anyway with INTR
>>> +         */
>>> +        if (!data->dready_trigger_on) {
>>> +            ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_INT_RST_LATCH,
>>> +                        BMG160_INT_MODE_LATCH_INT |
>>> +                        BMG160_INT_MODE_LATCH_RESET);
>>> +            if (ret < 0) {
>>> +                dev_err(&data->client->dev,
>>> +                    "Error writing reg_rst_latch\n");
>>> +                return ret;
>>> +            }
>>> +        }
>>> +
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_INT_EN_0,
>>> +                        BMG160_DATA_ENABLE_INT);
>>> +
>>> +    } else
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_INT_EN_0,
>>> +                        0);
>>> +
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_setup_new_data_interrupt(struct bmg160_data *data,
>>> +                       bool status)
>>> +{
>>> +    int ret;
>>> +
>>> +    /* Enable/Disable INT_MAP1 mapping */
>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_MAP_1);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error reading reg_int_map1\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    if (status)
>>> +        ret |= BMG160_INT_MAP_1_BIT_NEW_DATA;
>>> +    else
>>> +        ret &= ~BMG160_INT_MAP_1_BIT_NEW_DATA;
>>> +
>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>> +                    BMG160_REG_INT_MAP_1,
>>> +                    ret);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_int_map1\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    if (status) {
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_INT_RST_LATCH,
>>> +                        BMG160_INT_MODE_NON_LATCH_INT |
>>> +                        BMG160_INT_MODE_LATCH_RESET);
>>> +        if (ret < 0) {
>>> +            dev_err(&data->client->dev,
>>> +                "Error writing reg_rst_latch\n");
>>> +                return ret;
>>> +        }
>>> +
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_INT_EN_0,
>>> +                        BMG160_DATA_ENABLE_INT);
>>> +
>>> +    } else {
>>> +        /* Restore interrupt mode */
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_INT_RST_LATCH,
>>> +                        BMG160_INT_MODE_LATCH_INT |
>>> +                        BMG160_INT_MODE_LATCH_RESET);
>>> +        if (ret < 0) {
>>> +            dev_err(&data->client->dev,
>>> +                "Error writing reg_rst_latch\n");
>>> +                return ret;
>>> +        }
>>> +
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                        BMG160_REG_INT_EN_0,
>>> +                        0);
>>> +    }
>>> +
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_get_bw(struct bmg160_data *data, int *val)
>>> +{
>>> +    int i;
>>> +
>>> +    for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>>> +        if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
>>> +            *val = bmg160_samp_freq_table[i].val;
>>> +            return IIO_VAL_INT;
>>> +        }
>>> +    }
>>> +
>>> +    return -EINVAL;
>>> +}
>>> +
>>> +static int bmg160_set_scale(struct bmg160_data *data, int val)
>>> +{
>>> +    int ret, i;
>>> +
>>> +    for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>>> +        if (bmg160_scale_table[i].scale == val) {
>>> +            ret = i2c_smbus_write_byte_data(
>>> +                    data->client,
>>> +                    BMG160_REG_RANGE,
>>> +                    bmg160_scale_table[i].dps_range);
>>> +            if (ret < 0) {
>>> +                dev_err(&data->client->dev,
>>> +                    "Error writing reg_range\n");
>>> +                return ret;
>>> +            }
>>> +            data->dps_range = bmg160_scale_table[i].dps_range;
>>> +            return 0;
>>> +        }
>>> +    }
>>> +
>>> +    return -EINVAL;
>>> +}
>>> +
>>> +static int bmg160_get_temp(struct bmg160_data *data, int *val)
>>> +{
>>> +    int ret;
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +    ret = bmg160_set_power_state(data, true);
>>> +    if (ret < 0) {
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +
>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_TEMP);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error reading reg_temp\n");
>>> +        bmg160_set_power_state(data, false);
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +
>>> +    *val = sign_extend32(ret, 7);
>>> +    ret = bmg160_set_power_state(data, false);
>>> +    mutex_unlock(&data->mutex);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    return IIO_VAL_INT;
>>> +}
>>> +
>>> +static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
>>> +{
>>> +    int ret;
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +    ret = bmg160_set_power_state(data, true);
>>> +    if (ret < 0) {
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +
>>> +    ret = i2c_smbus_read_word_data(data->client, BMG160_AXIS_TO_REG(axis));
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error reading axis %d\n", axis);
>>> +        bmg160_set_power_state(data, false);
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +
>>> +    *val = sign_extend32(ret, 15);
>>> +    ret = bmg160_set_power_state(data, false);
>>> +    mutex_unlock(&data->mutex);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    return IIO_VAL_INT;
>>> +}
>>> +
>>> +static int bmg160_read_raw(struct iio_dev *indio_dev,
>>> +               struct iio_chan_spec const *chan,
>>> +               int *val, int *val2, long mask)
>>> +{
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int ret;
>>> +
>>> +    switch (mask) {
>>> +    case IIO_CHAN_INFO_RAW:
>>> +        switch (chan->type) {
>>> +        case IIO_TEMP:
>>> +            return bmg160_get_temp(data, val);
>>> +        case IIO_ANGL_VEL:
>>> +            if (iio_buffer_enabled(indio_dev))
>>> +                return -EBUSY;
>>> +            else
>>> +                return bmg160_get_axis(data, chan->scan_index,
>>> +                               val);
>>> +        default:
>>> +            return -EINVAL;
>>> +        }
>>> +    case IIO_CHAN_INFO_OFFSET:
>>> +        if (chan->type == IIO_TEMP) {
>>> +            *val = BMG160_TEMP_CENTER_VAL;
>>> +            return IIO_VAL_INT;
>>> +        } else
>>> +            return -EINVAL;
>>> +    case IIO_CHAN_INFO_SCALE:
>>> +        *val = 0;
>>> +        switch (chan->type) {
>>> +        case IIO_TEMP:
>>> +            *val2 = 500000;
>>> +            return IIO_VAL_INT_PLUS_MICRO;
>>> +        case IIO_ANGL_VEL:
>>> +        {
>>> +            int i;
>>> +
>>> +            for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>>> +                if (bmg160_scale_table[i].dps_range ==
>>> +                            data->dps_range) {
>>> +                    *val2 = bmg160_scale_table[i].scale;
>>> +                    return IIO_VAL_INT_PLUS_MICRO;
>>> +                }
>>> +            }
>>> +            return -EINVAL;
>>> +        }
>>> +        default:
>>> +            return -EINVAL;
>>> +        }
>>> +    case IIO_CHAN_INFO_SAMP_FREQ:
>>> +        *val2 = 0;
>>> +        mutex_lock(&data->mutex);
>>> +        ret = bmg160_get_bw(data, val);
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    default:
>>> +        return -EINVAL;
>>> +    }
>>> +}
>>> +
>>> +static int bmg160_write_raw(struct iio_dev *indio_dev,
>>> +                struct iio_chan_spec const *chan,
>>> +                int val, int val2, long mask)
>>> +{
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int ret;
>>> +
>>> +    switch (mask) {
>>> +    case IIO_CHAN_INFO_SAMP_FREQ:
>>> +        mutex_lock(&data->mutex);
>>> +        /*
>>> +         * Section 4.2 of spec
>>> +         * In suspend mode, the only supported operations are reading
>>> +         * registers as well as writing to the (0x14) softreset
>>> +         * register. Since we will be in suspend mode by default, change
>>> +         * mode to power on for other writes.
>>> +         */
>>> +        ret = bmg160_set_power_state(data, true);
>>> +        if (ret < 0) {
>>> +            mutex_unlock(&data->mutex);
>>> +            return ret;
>>> +        }
>>> +        ret = bmg160_set_bw(data, val);
>>> +        if (ret < 0) {
>>> +            bmg160_set_power_state(data, false);
>>> +            mutex_unlock(&data->mutex);
>>> +            return ret;
>>> +        }
>>> +        ret = bmg160_set_power_state(data, false);
>> Could this end up disabling the part when in triggered mode?
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    case IIO_CHAN_INFO_SCALE:
>>> +        if (val)
>>> +            return -EINVAL;
>>> +
>>> +        mutex_lock(&data->mutex);
>>> +        /* Refer to comments above for the suspend mode ops */
>>> +        ret = bmg160_set_power_state(data, true);
>>> +        if (ret < 0) {
>>> +            mutex_unlock(&data->mutex);
>>> +            return ret;
>>> +        }
>>> +        ret = bmg160_set_scale(data, val2);
>>> +        if (ret < 0) {
>>> +            bmg160_set_power_state(data, false);
>>> +            mutex_unlock(&data->mutex);
>>> +            return ret;
>>> +        }
>>> +        ret = bmg160_set_power_state(data, false);
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    default:
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    return -EINVAL;
>>> +}
>>> +
>>> +static int bmg160_read_event(struct iio_dev *indio_dev,
>>> +                 const struct iio_chan_spec *chan,
>>> +                 enum iio_event_type type,
>>> +                 enum iio_event_direction dir,
>>> +                 enum iio_event_info info,
>>> +                 int *val, int *val2)
>>> +{
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    *val2 = 0;
>>> +    switch (info) {
>>> +    case IIO_EV_INFO_VALUE:
>>> +        *val = data->slope_thres & BMG160_SLOPE_THRES_MASK;
>>> +        break;
>>> +    default:
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    return IIO_VAL_INT;
>>> +}
>>> +
>>> +static int bmg160_write_event(struct iio_dev *indio_dev,
>>> +                  const struct iio_chan_spec *chan,
>>> +                  enum iio_event_type type,
>>> +                  enum iio_event_direction dir,
>>> +                  enum iio_event_info info,
>>> +                  int val, int val2)
>>> +{
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    switch (info) {
>>> +    case IIO_EV_INFO_VALUE:
>>> +        if (data->ev_enable_state)
>>> +            return -EBUSY;
>>> +        data->slope_thres &= ~BMG160_SLOPE_THRES_MASK;
>>> +        data->slope_thres |= (val & BMG160_SLOPE_THRES_MASK);
>>> +        break;
>>> +    default:
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_read_event_config(struct iio_dev *indio_dev,
>>> +                    const struct iio_chan_spec *chan,
>>> +                    enum iio_event_type type,
>>> +                    enum iio_event_direction dir)
>>> +{
>>> +
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    return data->ev_enable_state;
>>> +}
>>> +
>>> +static int bmg160_write_event_config(struct iio_dev *indio_dev,
>>> +                     const struct iio_chan_spec *chan,
>>> +                     enum iio_event_type type,
>>> +                     enum iio_event_direction dir,
>>> +                     int state)
>>> +{
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int ret;
>>> +
>>> +    if (state && data->ev_enable_state)
>>> +        return 0;
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +
>>> +    if (!state && data->motion_trigger_on) {
>>> +        data->ev_enable_state = 0;
>>> +        mutex_unlock(&data->mutex);
>>> +        return 0;
>>> +    }
>>> +    /*
>>> +     * We will expect the enable and disable to do operation in
>>> +     * in reverse order. This will happen here anyway as our
>>> +     * resume operation uses sync mode runtime pm calls, the
>>> +     * suspend operation will be delayed by autosuspend delay
>>> +     * So the disable operation will still happen in reverse of
>>> +     * enable operation. When runtime pm is disabled the mode
>>> +     * is always on so sequence doesn't matter
>>> +     */
>> Thanks for the detailed comment!
>>> +    ret = bmg160_set_power_state(data, state);
>>> +    if (ret < 0) {
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +
>>> +    ret =  bmg160_setup_any_motion_interrupt(data, state);
>>> +    if (ret < 0) {
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +
>>> +    data->ev_enable_state = state;
>>> +    mutex_unlock(&data->mutex);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_validate_trigger(struct iio_dev *indio_dev,
>>> +                   struct iio_trigger *trig)
>>> +{
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    if (data->dready_trig != trig && data->motion_trig != trig)
>>> +        return -EINVAL;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 400 1000 2000");
>>> +
>>> +static IIO_CONST_ATTR(in_anglvel_scale_available,
>>> +              "0.001065 0.000532 0.000266 0.000133 0.000066");
>>> +
>>> +static struct attribute *bmg160_attributes[] = {
>>> +    &iio_const_attr_sampling_frequency_available.dev_attr.attr,
>>> +    &iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
>>> +    NULL,
>>> +};
>>> +
>>> +static const struct attribute_group bmg160_attrs_group = {
>>> +    .attrs = bmg160_attributes,
>>> +};
>>> +
>>> +static const struct iio_event_spec bmg160_event = {
>>> +        .type = IIO_EV_TYPE_ROC,
>>> +        .dir = IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING,
>>> +        .mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
>>> +                       BIT(IIO_EV_INFO_ENABLE)
>>> +};
>>> +
>>> +#define BMG160_CHANNEL(_axis) {                    \
>>> +    .type = IIO_ANGL_VEL,                        \
>>> +    .modified = 1,                            \
>>> +    .channel2 = IIO_MOD_##_axis,                    \
>>> +    .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),            \
>>> +    .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |        \
>>> +                    BIT(IIO_CHAN_INFO_SAMP_FREQ),    \
>>> +    .scan_index = AXIS_##_axis,                    \
>>> +    .scan_type = {                            \
>>> +        .sign = 's',                        \
>>> +        .realbits = 16,                    \
>>> +        .storagebits = 16,                    \
>>> +    },                                \
>>> +    .event_spec = &bmg160_event,                    \
>>> +    .num_event_specs = 1                        \
>>> +}
>>> +
>>> +static const struct iio_chan_spec bmg160_channels[] = {
>>> +    {
>>> +        .type = IIO_TEMP,
>>> +        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>>> +                      BIT(IIO_CHAN_INFO_SCALE) |
>>> +                      BIT(IIO_CHAN_INFO_OFFSET),
>>> +        .scan_index = -1,
>>> +    },
>>> +    BMG160_CHANNEL(X),
>>> +    BMG160_CHANNEL(Y),
>>> +    BMG160_CHANNEL(Z),
>>> +    IIO_CHAN_SOFT_TIMESTAMP(3),
>>> +};
>>> +
>>> +static const struct iio_info bmg160_info = {
>>> +    .attrs            = &bmg160_attrs_group,
>>> +    .read_raw        = bmg160_read_raw,
>>> +    .write_raw        = bmg160_write_raw,
>>> +    .read_event_value    = bmg160_read_event,
>>> +    .write_event_value    = bmg160_write_event,
>>> +    .write_event_config    = bmg160_write_event_config,
>>> +    .read_event_config    = bmg160_read_event_config,
>>> +    .validate_trigger    = bmg160_validate_trigger,
>>> +    .driver_module        = THIS_MODULE,
>>> +};
>>> +
>>> +static irqreturn_t bmg160_trigger_handler(int irq, void *p)
>>> +{
>>> +    struct iio_poll_func *pf = p;
>>> +    struct iio_dev *indio_dev = pf->indio_dev;
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int bit, ret, i = 0;
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +    for_each_set_bit(bit, indio_dev->buffer->scan_mask,
>>> +             indio_dev->masklength) {
>>> +        ret = i2c_smbus_read_word_data(data->client,
>>> +                           BMG160_AXIS_TO_REG(bit));
>>> +        if (ret < 0) {
>>> +            mutex_unlock(&data->mutex);
>>> +            goto err;
>>> +        }
>>> +        data->buffer[i++] = ret;
>>> +    }
>>> +    mutex_unlock(&data->mutex);
>>> +
>>> +    iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
>>> +                       data->timestamp);
>>> +err:
>>> +    iio_trigger_notify_done(indio_dev->trig);
>>> +
>>> +    return IRQ_HANDLED;
>>> +}
>>> +
>>> +static int bmg160_trig_try_reen(struct iio_trigger *trig)
>>> +{
>>> +    struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int ret;
>>> +
>>> +    /* new data interrupts don't need ack */
>>> +    if (data->dready_trigger_on)
>>> +        return 0;
>>> +
>>> +    /* Set latched mode interrupt and clear any latched interrupt */
>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>> +                    BMG160_REG_INT_RST_LATCH,
>>> +                    BMG160_INT_MODE_LATCH_INT |
>>> +                    BMG160_INT_MODE_LATCH_RESET);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_data_rdy_trigger_set_state(struct iio_trigger *trig,
>>> +                         bool state)
>>> +{
>>> +    struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int ret;
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +
>>> +    if (!state && data->ev_enable_state && data->motion_trigger_on) {
>>> +        data->motion_trigger_on = false;
>>> +        mutex_unlock(&data->mutex);
>>> +        return 0;
>>> +    }
>>> +
>>> +    /*
>>> +     * Refer to comment in bmg160_write_event_config for
>>> +     * enable/disable operation order
>>> +     */
>>> +    ret = bmg160_set_power_state(data, state);
>>> +    if (ret < 0) {
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +    if (data->motion_trig == trig)
>>> +        ret =  bmg160_setup_any_motion_interrupt(data, state);
>>> +    else
>>> +        ret = bmg160_setup_new_data_interrupt(data, state);
>>> +    if (ret < 0) {
>>> +        mutex_unlock(&data->mutex);
>>> +        return ret;
>>> +    }
>>> +    if (data->motion_trig == trig)
>>> +        data->motion_trigger_on = state;
>>> +    else
>>> +        data->dready_trigger_on = state;
>>> +
>>> +    mutex_unlock(&data->mutex);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static const struct iio_trigger_ops bmg160_trigger_ops = {
>>> +    .set_trigger_state = bmg160_data_rdy_trigger_set_state,
>>> +    .try_reenable = bmg160_trig_try_reen,
>>> +    .owner = THIS_MODULE,
>>> +};
>>> +
>>> +static irqreturn_t bmg160_event_handler(int irq, void *private)
>>> +{
>>> +    struct iio_dev *indio_dev = private;
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int ret;
>>> +    int dir;
>>> +
>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_STATUS_2);
>>> +    if (ret < 0) {
>>> +        dev_err(&data->client->dev, "Error reading reg_int_status2\n");
>>> +        goto ack_intr_status;
>>> +    }
>>> +
>>> +    if (ret & 0x08)
>>> +        dir = IIO_EV_DIR_RISING;
>>> +    else
>>> +        dir = IIO_EV_DIR_FALLING;
>>> +
>>> +    if (ret & BMG160_ANY_MOTION_MASK)
>>> +        iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
>>> +                            0,
>>> +                            IIO_MOD_X_OR_Y_OR_Z,
>>> +                            IIO_EV_TYPE_ROC,
>>> +                            dir),
>>> +                            data->timestamp);
>>> +
>>> +ack_intr_status:
>>> +    if (!data->dready_trigger_on) {
>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>> +                    BMG160_REG_INT_RST_LATCH,
>>> +                    BMG160_INT_MODE_LATCH_INT |
>>> +                    BMG160_INT_MODE_LATCH_RESET);
>>> +        if (ret < 0)
>>> +            dev_err(&data->client->dev,
>>> +                "Error writing reg_rst_latch\n");
>>> +    }
>>> +
>>> +    return IRQ_HANDLED;
>>> +}
>>> +
>>> +static irqreturn_t bmg160_data_rdy_trig_poll(int irq, void *private)
>>> +{
>>> +    struct iio_dev *indio_dev = private;
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    data->timestamp = iio_get_time_ns();
>>> +
>>> +    if (data->dready_trigger_on)
>>> +        iio_trigger_poll(data->dready_trig);
>>> +    else if (data->motion_trigger_on)
>>> +        iio_trigger_poll(data->motion_trig);
>>> +
>>> +    if (data->ev_enable_state)
>>> +        return IRQ_WAKE_THREAD;
>>> +    else
>>> +        return IRQ_HANDLED;
>>> +
>>> +}
>>> +
>>> +static int bmg160_acpi_gpio_probe(struct i2c_client *client,
>>> +                  struct bmg160_data *data)
>>> +{
>>> +    const struct acpi_device_id *id;
>>> +    struct device *dev;
>>> +    struct gpio_desc *gpio;
>>> +    int ret;
>>> +
>>> +    if (!client)
>>> +        return -EINVAL;
>>> +
>>> +    dev = &client->dev;
>>> +    if (!ACPI_HANDLE(dev))
>>> +        return -ENODEV;
>>> +
>>> +    id = acpi_match_device(dev->driver->acpi_match_table, dev);
>>> +    if (!id)
>>> +        return -ENODEV;
>>> +
>>> +    /* data ready gpio interrupt pin */
>>> +    gpio = devm_gpiod_get_index(dev, BMG160_GPIO_NAME, 0);
>>> +    if (IS_ERR(gpio)) {
>>> +        dev_err(dev, "acpi gpio get index failed\n");
>>> +        return PTR_ERR(gpio);
>>> +    }
>>> +
>>> +    ret = gpiod_direction_input(gpio);
>>> +    if (ret)
>>> +        return ret;
>>> +
>>> +    ret = gpiod_to_irq(gpio);
>>> +
>>> +    dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
>>> +
>>> +    return ret;
>>> +}
>>> +
>>> +static int bmg160_probe(struct i2c_client *client,
>>> +            const struct i2c_device_id *id)
>>> +{
>>> +    struct bmg160_data *data;
>>> +    struct iio_dev *indio_dev;
>>> +    int ret;
>>> +
>>> +    indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>>> +    if (!indio_dev)
>>> +        return -ENOMEM;
>>> +
>>> +    data = iio_priv(indio_dev);
>>> +    i2c_set_clientdata(client, indio_dev);
>>> +    data->client = client;
>>> +
>>> +    ret = bmg160_chip_init(data);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    mutex_init(&data->mutex);
>>> +
>>> +    indio_dev->dev.parent = &client->dev;
>>> +    indio_dev->channels = bmg160_channels;
>>> +    indio_dev->num_channels = ARRAY_SIZE(bmg160_channels);
>>> +    indio_dev->name = BMG160_DRV_NAME;
>>> +    indio_dev->modes = INDIO_DIRECT_MODE;
>>> +    indio_dev->info = &bmg160_info;
>>> +
>>> +    if (client->irq <= 0)
>>> +        client->irq = bmg160_acpi_gpio_probe(client, data);
>>> +
>>> +    if (client->irq > 0) {
>>> +        ret = devm_request_threaded_irq(&client->dev,
>>> +                        client->irq,
>>> +                        bmg160_data_rdy_trig_poll,
>>> +                        bmg160_event_handler,
>>> +                        IRQF_TRIGGER_RISING,
>>> +                        BMG160_IRQ_NAME,
>>> +                        indio_dev);
>>> +        if (ret)
>>> +            return ret;
>>> +
>>> +        data->dready_trig = devm_iio_trigger_alloc(&client->dev,
>>> +                               "%s-dev%d",
>>> +                               indio_dev->name,
>>> +                               indio_dev->id);
>>> +        if (!data->dready_trig)
>>> +            return -ENOMEM;
>>> +
>>> +        data->motion_trig = devm_iio_trigger_alloc(&client->dev,
>>> +                              "%s-any-motion-dev%d",
>>> +                              indio_dev->name,
>>> +                              indio_dev->id);
>>> +        if (!data->motion_trig)
>>> +            return -ENOMEM;
>>> +
>>> +        data->dready_trig->dev.parent = &client->dev;
>>> +        data->dready_trig->ops = &bmg160_trigger_ops;
>>> +        iio_trigger_set_drvdata(data->dready_trig, indio_dev);
>>> +        ret = iio_trigger_register(data->dready_trig);
>>> +        if (ret)
>>> +            return ret;
>>> +
>>> +        data->motion_trig->dev.parent = &client->dev;
>>> +        data->motion_trig->ops = &bmg160_trigger_ops;
>>> +        iio_trigger_set_drvdata(data->motion_trig, indio_dev);
>>> +        ret = iio_trigger_register(data->motion_trig);
>>> +        if (ret) {
>>> +            data->motion_trig = NULL;
>>> +            goto err_trigger_unregister;
>>> +        }
>>> +
>>> +        ret = iio_triggered_buffer_setup(indio_dev,
>>> +                         NULL,
>>> +                         bmg160_trigger_handler,
>>> +                         NULL);
>>> +        if (ret < 0) {
>>> +            dev_err(&client->dev,
>>> +                "iio triggered buffer setup failed\n");
>>> +            goto err_trigger_unregister;
>>> +        }
>>> +    }
>>> +
>>> +    ret = iio_device_register(indio_dev);
>>> +    if (ret < 0) {
>>> +        dev_err(&client->dev, "unable to register iio device\n");
>>> +        goto err_buffer_cleanup;
>>> +    }
>>> +
>>> +    ret = pm_runtime_set_active(&client->dev);
>>> +    if (ret)
>>> +        goto err_iio_unregister;
>>> +
>>> +    pm_runtime_enable(&client->dev);
>>> +    pm_runtime_set_autosuspend_delay(&client->dev,
>>> +                     BMG160_AUTO_SUSPEND_DELAY_MS);
>>> +    pm_runtime_use_autosuspend(&client->dev);
>>> +
>>> +    return 0;
>>> +
>>> +err_iio_unregister:
>>> +    iio_device_unregister(indio_dev);
>>> +err_buffer_cleanup:
>>> +    if (data->dready_trig)
>>> +        iio_triggered_buffer_cleanup(indio_dev);
>>> +err_trigger_unregister:
>>> +    if (data->dready_trig)
>>> +        iio_trigger_unregister(data->dready_trig);
>>> +    if (data->motion_trig)
>>> +        iio_trigger_unregister(data->motion_trig);
>>> +
>>> +    return ret;
>>> +}
>>> +
>>> +static int bmg160_remove(struct i2c_client *client)
>>> +{
>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(client);
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    pm_runtime_disable(&client->dev);
>>> +    pm_runtime_set_suspended(&client->dev);
>>> +    pm_runtime_put_noidle(&client->dev);
>>> +
>>> +    iio_device_unregister(indio_dev);
>>> +
>>> +    if (data->dready_trig) {
>>> +        iio_triggered_buffer_cleanup(indio_dev);
>>> +        iio_trigger_unregister(data->dready_trig);
>>> +        iio_trigger_unregister(data->motion_trig);
>>> +    }
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +    bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
>>> +    mutex_unlock(&data->mutex);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +#ifdef CONFIG_PM_SLEEP
>>> +static int bmg160_suspend(struct device *dev)
>>> +{
>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +    bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>>> +    mutex_unlock(&data->mutex);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int bmg160_resume(struct device *dev)
>>> +{
>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    mutex_lock(&data->mutex);
>>> +    if (data->dready_trigger_on || data->motion_trigger_on ||
>>> +                            data->ev_enable_state)
>>> +        bmg160_set_mode(data, BMG160_MODE_NORMAL);
>>> +    mutex_unlock(&data->mutex);
>>> +
>>> +    return 0;
>>> +}
>>> +#endif
>>> +
>>> +#ifdef CONFIG_PM_RUNTIME
>>> +static int bmg160_runtime_suspend(struct device *dev)
>>> +{
>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +
>>> +    return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>>> +}
>>> +
>>> +static int bmg160_runtime_resume(struct device *dev)
>>> +{
>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>> +    int ret;
>>> +
>>> +    ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
>>> +
>>> +    return 0;
>>> +}
>>> +#endif
>>> +
>>> +static const struct dev_pm_ops bmg160_pm_ops = {
>>> +    SET_SYSTEM_SLEEP_PM_OPS(bmg160_suspend, bmg160_resume)
>>> +    SET_RUNTIME_PM_OPS(bmg160_runtime_suspend,
>>> +               bmg160_runtime_resume, NULL)
>>> +};
>>> +
>>> +static const struct acpi_device_id bmg160_acpi_match[] = {
>>> +    {"BMG0160", 0},
>>> +    { },
>>> +};
>>> +MODULE_DEVICE_TABLE(acpi, bmg160_acpi_match);
>>> +
>>> +static const struct i2c_device_id bmg160_id[] = {
>>> +    {"bmg160", 0},
>>> +    {}
>>> +};
>>> +
>>> +MODULE_DEVICE_TABLE(i2c, bmg160_id);
>>> +
>>> +static struct i2c_driver bmg160_driver = {
>>> +    .driver = {
>>> +        .name    = BMG160_DRV_NAME,
>>> +        .acpi_match_table = ACPI_PTR(bmg160_acpi_match),
>>> +        .pm    = &bmg160_pm_ops,
>>> +    },
>>> +    .probe        = bmg160_probe,
>>> +    .remove        = bmg160_remove,
>>> +    .id_table    = bmg160_id,
>>> +};
>>> +module_i2c_driver(bmg160_driver);
>>> +
>>> +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
>>> +MODULE_LICENSE("GPL v2");
>>> +MODULE_DESCRIPTION("BMG160 Gyro driver");
>>>
>>
> 

Re: [PATCH v3 1/2] iio:gyro:bmg160 Gyro Sensor driver

[Jonathan Cameron]

On 19/08/14 20:51, Jonathan Cameron wrote:
> On 12/08/14 20:06, Srinivas Pandruvada wrote:
>> On 08/07/2014 03:39 AM, Jonathan Cameron wrote:
>>> On 05/08/14 22:57, Srinivas Pandruvada wrote:
>>>> This change implements support for BMG160 Gyro sensor. Although chip
>>>> has several advanced features, this change implements minimum set
>>>> required for using gyro sensor.
>>>>
>>>> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
>>> One more query.  In the write_raw function you always enable then suspend the
>>> device.  The enable is safe, but if you have a write to the attributes
>>> whilst operating in triggered / buffered mode will it not disable the
>>> device?  It is perfectly permissible to ignore such a write (return -EBUSY)
>>> but I don't think you are doing so.
>>>
>>
>> I tested this. When trigger/events are active then first call to bmg160_set_power_state will increment runtime pm
>> refcount and also execute runtime resume to change the mode to NORMAL.
>> But when write_raw is called while the trigger/events are active the runtime PM refcount is incremented since it was
>> already more than 0, so the resume is not actually called. When at the end of write_raw bmg160_set_power_state to turn
>> off, the ref count is simply decremented, but since it is not zero, runtime suspend will not be called.
>>
> Sorry, managed to loose this driver so will pick it up after Greg
> has taken the pull request I'm just sending.
> 
> Not exactly a lack of time at this point in the cycle ;)
Applied to the togreg branch of iio.git - initially pushed out as testing for
the autobuilders to play.

Thanks,

Jonathan
> 
>> Thanks,
>> Srinivas
>>
>>> Otherwise, looks good to me.  Nice explanatory comments as well!
>>>> ---
>>>>   drivers/iio/gyro/Kconfig  |   11 +
>>>>   drivers/iio/gyro/Makefile |    1 +
>>>>   drivers/iio/gyro/bmg160.c | 1211 +++++++++++++++++++++++++++++++++++++++++++++
>>>>   3 files changed, 1223 insertions(+)
>>>>   create mode 100644 drivers/iio/gyro/bmg160.c
>>>>
>>>> diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
>>>> index ac2d69e..d630ae9 100644
>>>> --- a/drivers/iio/gyro/Kconfig
>>>> +++ b/drivers/iio/gyro/Kconfig
>>>> @@ -50,6 +50,17 @@ config ADXRS450
>>>>         This driver can also be built as a module.  If so, the module
>>>>         will be called adxrs450.
>>>>
>>>> +config BMG160
>>>> +    tristate "BOSCH BMG160 Gyro Sensor"
>>>> +    depends on I2C
>>>> +    select IIO_TRIGGERED_BUFFER if IIO_BUFFER
>>>> +    help
>>>> +      Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
>>>> +      driver.
>>>> +
>>>> +      This driver can also be built as a module.  If so, the module
>>>> +      will be called bmg160.
>>>> +
>>>>   config HID_SENSOR_GYRO_3D
>>>>       depends on HID_SENSOR_HUB
>>>>       select IIO_BUFFER
>>>> diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
>>>> index 2f2752a..36a3877 100644
>>>> --- a/drivers/iio/gyro/Makefile
>>>> +++ b/drivers/iio/gyro/Makefile
>>>> @@ -8,6 +8,7 @@ obj-$(CONFIG_ADIS16130) += adis16130.o
>>>>   obj-$(CONFIG_ADIS16136) += adis16136.o
>>>>   obj-$(CONFIG_ADIS16260) += adis16260.o
>>>>   obj-$(CONFIG_ADXRS450) += adxrs450.o
>>>> +obj-$(CONFIG_BMG160) += bmg160.o
>>>>
>>>>   obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
>>>>
>>>> diff --git a/drivers/iio/gyro/bmg160.c b/drivers/iio/gyro/bmg160.c
>>>> new file mode 100644
>>>> index 0000000..80f92a6
>>>> --- /dev/null
>>>> +++ b/drivers/iio/gyro/bmg160.c
>>>> @@ -0,0 +1,1211 @@
>>>> +/*
>>>> + * BMG160 Gyro Sensor driver
>>>> + * Copyright (c) 2014, Intel Corporation.
>>>> + *
>>>> + * This program is free software; you can redistribute it and/or modify it
>>>> + * under the terms and conditions of the GNU General Public License,
>>>> + * version 2, as published by the Free Software Foundation.
>>>> + *
>>>> + * This program is distributed in the hope it will be useful, but WITHOUT
>>>> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
>>>> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
>>>> + * more details.
>>>> + */
>>>> +
>>>> +#include <linux/module.h>
>>>> +#include <linux/i2c.h>
>>>> +#include <linux/interrupt.h>
>>>> +#include <linux/delay.h>
>>>> +#include <linux/slab.h>
>>>> +#include <linux/acpi.h>
>>>> +#include <linux/gpio/consumer.h>
>>>> +#include <linux/pm.h>
>>>> +#include <linux/pm_runtime.h>
>>>> +#include <linux/iio/iio.h>
>>>> +#include <linux/iio/sysfs.h>
>>>> +#include <linux/iio/buffer.h>
>>>> +#include <linux/iio/trigger.h>
>>>> +#include <linux/iio/events.h>
>>>> +#include <linux/iio/trigger_consumer.h>
>>>> +#include <linux/iio/triggered_buffer.h>
>>>> +
>>>> +#define BMG160_DRV_NAME        "bmg160"
>>>> +#define BMG160_IRQ_NAME        "bmg160_event"
>>>> +#define BMG160_GPIO_NAME        "gpio_int"
>>>> +
>>>> +#define BMG160_REG_CHIP_ID        0x00
>>>> +#define BMG160_CHIP_ID_VAL        0x0F
>>>> +
>>>> +#define BMG160_REG_PMU_LPW        0x11
>>>> +#define BMG160_MODE_NORMAL        0x00
>>>> +#define BMG160_MODE_DEEP_SUSPEND    0x20
>>>> +#define BMG160_MODE_SUSPEND        0x80
>>>> +
>>>> +#define BMG160_REG_RANGE        0x0F
>>>> +
>>>> +#define BMG160_RANGE_2000DPS        0
>>>> +#define BMG160_RANGE_1000DPS        1
>>>> +#define BMG160_RANGE_500DPS        2
>>>> +#define BMG160_RANGE_250DPS        3
>>>> +#define BMG160_RANGE_125DPS        4
>>>> +
>>>> +#define BMG160_REG_PMU_BW        0x10
>>>> +#define BMG160_NO_FILTER        0
>>>> +#define BMG160_DEF_BW            100
>>>> +
>>>> +#define BMG160_REG_INT_MAP_0        0x17
>>>> +#define BMG160_INT_MAP_0_BIT_ANY    BIT(1)
>>>> +
>>>> +#define BMG160_REG_INT_MAP_1        0x18
>>>> +#define BMG160_INT_MAP_1_BIT_NEW_DATA    BIT(0)
>>>> +
>>>> +#define BMG160_REG_INT_RST_LATCH    0x21
>>>> +#define BMG160_INT_MODE_LATCH_RESET    0x80
>>>> +#define BMG160_INT_MODE_LATCH_INT    0x0F
>>>> +#define BMG160_INT_MODE_NON_LATCH_INT    0x00
>>>> +
>>>> +#define BMG160_REG_INT_EN_0        0x15
>>>> +#define BMG160_DATA_ENABLE_INT        BIT(7)
>>>> +
>>>> +#define BMG160_REG_XOUT_L        0x02
>>>> +#define BMG160_AXIS_TO_REG(axis)    (BMG160_REG_XOUT_L + (axis * 2))
>>>> +
>>>> +#define BMG160_REG_SLOPE_THRES        0x1B
>>>> +#define BMG160_SLOPE_THRES_MASK    0x0F
>>>> +
>>>> +#define BMG160_REG_MOTION_INTR        0x1C
>>>> +#define BMG160_INT_MOTION_X        BIT(0)
>>>> +#define BMG160_INT_MOTION_Y        BIT(1)
>>>> +#define BMG160_INT_MOTION_Z        BIT(2)
>>>> +#define BMG160_ANY_DUR_MASK        0x30
>>>> +#define BMG160_ANY_DUR_SHIFT        4
>>>> +
>>>> +#define BMG160_REG_INT_STATUS_2    0x0B
>>>> +#define BMG160_ANY_MOTION_MASK        0x07
>>>> +
>>>> +#define BMG160_REG_TEMP        0x08
>>>> +#define BMG160_TEMP_CENTER_VAL        23
>>>> +
>>>> +#define BMG160_MAX_STARTUP_TIME_MS    80
>>>> +
>>>> +#define BMG160_AUTO_SUSPEND_DELAY_MS    2000
>>>> +
>>>> +struct bmg160_data {
>>>> +    struct i2c_client *client;
>>>> +    struct iio_trigger *dready_trig;
>>>> +    struct iio_trigger *motion_trig;
>>>> +    struct mutex mutex;
>>>> +    s16 buffer[8];
>>>> +    u8 bw_bits;
>>>> +    u32 dps_range;
>>>> +    int ev_enable_state;
>>>> +    int slope_thres;
>>>> +    bool dready_trigger_on;
>>>> +    bool motion_trigger_on;
>>>> +    int64_t timestamp;
>>>> +};
>>>> +
>>>> +enum bmg160_axis {
>>>> +    AXIS_X,
>>>> +    AXIS_Y,
>>>> +    AXIS_Z,
>>>> +};
>>>> +
>>>> +static const struct {
>>>> +    int val;
>>>> +    int bw_bits;
>>>> +} bmg160_samp_freq_table[] = { {100, 0x07},
>>>> +                   {200, 0x06},
>>>> +                   {400, 0x03},
>>>> +                   {1000, 0x02},
>>>> +                   {2000, 0x01} };
>>>> +
>>>> +static const struct {
>>>> +    int scale;
>>>> +    int dps_range;
>>>> +} bmg160_scale_table[] = { { 1065, BMG160_RANGE_2000DPS},
>>>> +               { 532, BMG160_RANGE_1000DPS},
>>>> +               { 266, BMG160_RANGE_500DPS},
>>>> +               { 133, BMG160_RANGE_250DPS},
>>>> +               { 66, BMG160_RANGE_125DPS} };
>>>> +
>>>> +static int bmg160_set_mode(struct bmg160_data *data, u8 mode)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>>> +                    BMG160_REG_PMU_LPW, mode);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_pmu_lpw\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_convert_freq_to_bit(int val)
>>>> +{
>>>> +    int i;
>>>> +
>>>> +    for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>>>> +        if (bmg160_samp_freq_table[i].val == val)
>>>> +            return bmg160_samp_freq_table[i].bw_bits;
>>>> +    }
>>>> +
>>>> +    return -EINVAL;
>>>> +}
>>>> +
>>>> +static int bmg160_set_bw(struct bmg160_data *data, int val)
>>>> +{
>>>> +    int ret;
>>>> +    int bw_bits;
>>>> +
>>>> +    bw_bits = bmg160_convert_freq_to_bit(val);
>>>> +    if (bw_bits < 0)
>>>> +        return bw_bits;
>>>> +
>>>> +    ret = i2c_smbus_write_byte_data(data->client, BMG160_REG_PMU_BW,
>>>> +                    bw_bits);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_pmu_bw\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    data->bw_bits = bw_bits;
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_chip_init(struct bmg160_data *data)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_CHIP_ID);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error reading reg_chip_id\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
>>>> +    if (ret != BMG160_CHIP_ID_VAL) {
>>>> +        dev_err(&data->client->dev, "invalid chip %x\n", ret);
>>>> +        return -ENODEV;
>>>> +    }
>>>> +
>>>> +    ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>>>> +    if (ret < 0)
>>>> +        return ret;
>>>> +
>>>> +    /* Wait upto 500 ms to be ready after changing mode */
>>>> +    usleep_range(500, 1000);
>>>> +
>>>> +    /* Set Bandwidth */
>>>> +    ret = bmg160_set_bw(data, BMG160_DEF_BW);
>>>> +    if (ret < 0)
>>>> +        return ret;
>>>> +
>>>> +    /* Set Default Range */
>>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>>> +                    BMG160_REG_RANGE,
>>>> +                    BMG160_RANGE_500DPS);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_range\n");
>>>> +        return ret;
>>>> +    }
>>>> +    data->dps_range = BMG160_RANGE_500DPS;
>>>> +
>>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_SLOPE_THRES);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error reading reg_slope_thres\n");
>>>> +        return ret;
>>>> +    }
>>>> +    data->slope_thres = ret;
>>>> +
>>>> +    /* Set default interrupt mode */
>>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>>> +                    BMG160_REG_INT_RST_LATCH,
>>>> +                    BMG160_INT_MODE_LATCH_INT |
>>>> +                    BMG160_INT_MODE_LATCH_RESET);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev,
>>>> +            "Error writing reg_motion_intr\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_set_power_state(struct bmg160_data *data, bool on)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    if (on)
>>>> +        ret = pm_runtime_get_sync(&data->client->dev);
>>>> +    else {
>>>> +        pm_runtime_mark_last_busy(&data->client->dev);
>>>> +        ret = pm_runtime_put_autosuspend(&data->client->dev);
>>>> +    }
>>>> +
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev,
>>>> +            "Failed: bmg160_set_power_state for %d\n", on);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_setup_any_motion_interrupt(struct bmg160_data *data,
>>>> +                         bool status)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    /* Enable/Disable INT_MAP0 mapping */
>>>> +    ret = i2c_smbus_read_byte_data(data->client,  BMG160_REG_INT_MAP_0);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error reading reg_int_map0\n");
>>>> +        return ret;
>>>> +    }
>>>> +    if (status)
>>>> +        ret |= BMG160_INT_MAP_0_BIT_ANY;
>>>> +    else
>>>> +        ret &= ~BMG160_INT_MAP_0_BIT_ANY;
>>>> +
>>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>>> +                    BMG160_REG_INT_MAP_0,
>>>> +                    ret);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_int_map0\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    /* Enable/Disable slope interrupts */
>>>> +    if (status) {
>>>> +        /* Update slope thres */
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_SLOPE_THRES,
>>>> +                        data->slope_thres);
>>>> +        if (ret < 0) {
>>>> +            dev_err(&data->client->dev,
>>>> +                "Error writing reg_slope_thres\n");
>>>> +            return ret;
>>>> +        }
>>>> +
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_MOTION_INTR,
>>>> +                        BMG160_INT_MOTION_X |
>>>> +                        BMG160_INT_MOTION_Y |
>>>> +                        BMG160_INT_MOTION_Z);
>>>> +        if (ret < 0) {
>>>> +            dev_err(&data->client->dev,
>>>> +                "Error writing reg_motion_intr\n");
>>>> +            return ret;
>>>> +        }
>>>> +
>>>> +        /*
>>>> +         * New data interrupt is always non-latched,
>>>> +         * which will have higher priority, so no need
>>>> +         * to set latched mode, we will be flooded anyway with INTR
>>>> +         */
>>>> +        if (!data->dready_trigger_on) {
>>>> +            ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_INT_RST_LATCH,
>>>> +                        BMG160_INT_MODE_LATCH_INT |
>>>> +                        BMG160_INT_MODE_LATCH_RESET);
>>>> +            if (ret < 0) {
>>>> +                dev_err(&data->client->dev,
>>>> +                    "Error writing reg_rst_latch\n");
>>>> +                return ret;
>>>> +            }
>>>> +        }
>>>> +
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_INT_EN_0,
>>>> +                        BMG160_DATA_ENABLE_INT);
>>>> +
>>>> +    } else
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_INT_EN_0,
>>>> +                        0);
>>>> +
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_setup_new_data_interrupt(struct bmg160_data *data,
>>>> +                       bool status)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    /* Enable/Disable INT_MAP1 mapping */
>>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_MAP_1);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error reading reg_int_map1\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    if (status)
>>>> +        ret |= BMG160_INT_MAP_1_BIT_NEW_DATA;
>>>> +    else
>>>> +        ret &= ~BMG160_INT_MAP_1_BIT_NEW_DATA;
>>>> +
>>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>>> +                    BMG160_REG_INT_MAP_1,
>>>> +                    ret);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_int_map1\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    if (status) {
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_INT_RST_LATCH,
>>>> +                        BMG160_INT_MODE_NON_LATCH_INT |
>>>> +                        BMG160_INT_MODE_LATCH_RESET);
>>>> +        if (ret < 0) {
>>>> +            dev_err(&data->client->dev,
>>>> +                "Error writing reg_rst_latch\n");
>>>> +                return ret;
>>>> +        }
>>>> +
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_INT_EN_0,
>>>> +                        BMG160_DATA_ENABLE_INT);
>>>> +
>>>> +    } else {
>>>> +        /* Restore interrupt mode */
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_INT_RST_LATCH,
>>>> +                        BMG160_INT_MODE_LATCH_INT |
>>>> +                        BMG160_INT_MODE_LATCH_RESET);
>>>> +        if (ret < 0) {
>>>> +            dev_err(&data->client->dev,
>>>> +                "Error writing reg_rst_latch\n");
>>>> +                return ret;
>>>> +        }
>>>> +
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                        BMG160_REG_INT_EN_0,
>>>> +                        0);
>>>> +    }
>>>> +
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_int_en0\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_get_bw(struct bmg160_data *data, int *val)
>>>> +{
>>>> +    int i;
>>>> +
>>>> +    for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
>>>> +        if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
>>>> +            *val = bmg160_samp_freq_table[i].val;
>>>> +            return IIO_VAL_INT;
>>>> +        }
>>>> +    }
>>>> +
>>>> +    return -EINVAL;
>>>> +}
>>>> +
>>>> +static int bmg160_set_scale(struct bmg160_data *data, int val)
>>>> +{
>>>> +    int ret, i;
>>>> +
>>>> +    for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>>>> +        if (bmg160_scale_table[i].scale == val) {
>>>> +            ret = i2c_smbus_write_byte_data(
>>>> +                    data->client,
>>>> +                    BMG160_REG_RANGE,
>>>> +                    bmg160_scale_table[i].dps_range);
>>>> +            if (ret < 0) {
>>>> +                dev_err(&data->client->dev,
>>>> +                    "Error writing reg_range\n");
>>>> +                return ret;
>>>> +            }
>>>> +            data->dps_range = bmg160_scale_table[i].dps_range;
>>>> +            return 0;
>>>> +        }
>>>> +    }
>>>> +
>>>> +    return -EINVAL;
>>>> +}
>>>> +
>>>> +static int bmg160_get_temp(struct bmg160_data *data, int *val)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +    ret = bmg160_set_power_state(data, true);
>>>> +    if (ret < 0) {
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_TEMP);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error reading reg_temp\n");
>>>> +        bmg160_set_power_state(data, false);
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    *val = sign_extend32(ret, 7);
>>>> +    ret = bmg160_set_power_state(data, false);
>>>> +    mutex_unlock(&data->mutex);
>>>> +    if (ret < 0)
>>>> +        return ret;
>>>> +
>>>> +    return IIO_VAL_INT;
>>>> +}
>>>> +
>>>> +static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +    ret = bmg160_set_power_state(data, true);
>>>> +    if (ret < 0) {
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    ret = i2c_smbus_read_word_data(data->client, BMG160_AXIS_TO_REG(axis));
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error reading axis %d\n", axis);
>>>> +        bmg160_set_power_state(data, false);
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    *val = sign_extend32(ret, 15);
>>>> +    ret = bmg160_set_power_state(data, false);
>>>> +    mutex_unlock(&data->mutex);
>>>> +    if (ret < 0)
>>>> +        return ret;
>>>> +
>>>> +    return IIO_VAL_INT;
>>>> +}
>>>> +
>>>> +static int bmg160_read_raw(struct iio_dev *indio_dev,
>>>> +               struct iio_chan_spec const *chan,
>>>> +               int *val, int *val2, long mask)
>>>> +{
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int ret;
>>>> +
>>>> +    switch (mask) {
>>>> +    case IIO_CHAN_INFO_RAW:
>>>> +        switch (chan->type) {
>>>> +        case IIO_TEMP:
>>>> +            return bmg160_get_temp(data, val);
>>>> +        case IIO_ANGL_VEL:
>>>> +            if (iio_buffer_enabled(indio_dev))
>>>> +                return -EBUSY;
>>>> +            else
>>>> +                return bmg160_get_axis(data, chan->scan_index,
>>>> +                               val);
>>>> +        default:
>>>> +            return -EINVAL;
>>>> +        }
>>>> +    case IIO_CHAN_INFO_OFFSET:
>>>> +        if (chan->type == IIO_TEMP) {
>>>> +            *val = BMG160_TEMP_CENTER_VAL;
>>>> +            return IIO_VAL_INT;
>>>> +        } else
>>>> +            return -EINVAL;
>>>> +    case IIO_CHAN_INFO_SCALE:
>>>> +        *val = 0;
>>>> +        switch (chan->type) {
>>>> +        case IIO_TEMP:
>>>> +            *val2 = 500000;
>>>> +            return IIO_VAL_INT_PLUS_MICRO;
>>>> +        case IIO_ANGL_VEL:
>>>> +        {
>>>> +            int i;
>>>> +
>>>> +            for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
>>>> +                if (bmg160_scale_table[i].dps_range ==
>>>> +                            data->dps_range) {
>>>> +                    *val2 = bmg160_scale_table[i].scale;
>>>> +                    return IIO_VAL_INT_PLUS_MICRO;
>>>> +                }
>>>> +            }
>>>> +            return -EINVAL;
>>>> +        }
>>>> +        default:
>>>> +            return -EINVAL;
>>>> +        }
>>>> +    case IIO_CHAN_INFO_SAMP_FREQ:
>>>> +        *val2 = 0;
>>>> +        mutex_lock(&data->mutex);
>>>> +        ret = bmg160_get_bw(data, val);
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +}
>>>> +
>>>> +static int bmg160_write_raw(struct iio_dev *indio_dev,
>>>> +                struct iio_chan_spec const *chan,
>>>> +                int val, int val2, long mask)
>>>> +{
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int ret;
>>>> +
>>>> +    switch (mask) {
>>>> +    case IIO_CHAN_INFO_SAMP_FREQ:
>>>> +        mutex_lock(&data->mutex);
>>>> +        /*
>>>> +         * Section 4.2 of spec
>>>> +         * In suspend mode, the only supported operations are reading
>>>> +         * registers as well as writing to the (0x14) softreset
>>>> +         * register. Since we will be in suspend mode by default, change
>>>> +         * mode to power on for other writes.
>>>> +         */
>>>> +        ret = bmg160_set_power_state(data, true);
>>>> +        if (ret < 0) {
>>>> +            mutex_unlock(&data->mutex);
>>>> +            return ret;
>>>> +        }
>>>> +        ret = bmg160_set_bw(data, val);
>>>> +        if (ret < 0) {
>>>> +            bmg160_set_power_state(data, false);
>>>> +            mutex_unlock(&data->mutex);
>>>> +            return ret;
>>>> +        }
>>>> +        ret = bmg160_set_power_state(data, false);
>>> Could this end up disabling the part when in triggered mode?
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    case IIO_CHAN_INFO_SCALE:
>>>> +        if (val)
>>>> +            return -EINVAL;
>>>> +
>>>> +        mutex_lock(&data->mutex);
>>>> +        /* Refer to comments above for the suspend mode ops */
>>>> +        ret = bmg160_set_power_state(data, true);
>>>> +        if (ret < 0) {
>>>> +            mutex_unlock(&data->mutex);
>>>> +            return ret;
>>>> +        }
>>>> +        ret = bmg160_set_scale(data, val2);
>>>> +        if (ret < 0) {
>>>> +            bmg160_set_power_state(data, false);
>>>> +            mutex_unlock(&data->mutex);
>>>> +            return ret;
>>>> +        }
>>>> +        ret = bmg160_set_power_state(data, false);
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    return -EINVAL;
>>>> +}
>>>> +
>>>> +static int bmg160_read_event(struct iio_dev *indio_dev,
>>>> +                 const struct iio_chan_spec *chan,
>>>> +                 enum iio_event_type type,
>>>> +                 enum iio_event_direction dir,
>>>> +                 enum iio_event_info info,
>>>> +                 int *val, int *val2)
>>>> +{
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    *val2 = 0;
>>>> +    switch (info) {
>>>> +    case IIO_EV_INFO_VALUE:
>>>> +        *val = data->slope_thres & BMG160_SLOPE_THRES_MASK;
>>>> +        break;
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    return IIO_VAL_INT;
>>>> +}
>>>> +
>>>> +static int bmg160_write_event(struct iio_dev *indio_dev,
>>>> +                  const struct iio_chan_spec *chan,
>>>> +                  enum iio_event_type type,
>>>> +                  enum iio_event_direction dir,
>>>> +                  enum iio_event_info info,
>>>> +                  int val, int val2)
>>>> +{
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    switch (info) {
>>>> +    case IIO_EV_INFO_VALUE:
>>>> +        if (data->ev_enable_state)
>>>> +            return -EBUSY;
>>>> +        data->slope_thres &= ~BMG160_SLOPE_THRES_MASK;
>>>> +        data->slope_thres |= (val & BMG160_SLOPE_THRES_MASK);
>>>> +        break;
>>>> +    default:
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_read_event_config(struct iio_dev *indio_dev,
>>>> +                    const struct iio_chan_spec *chan,
>>>> +                    enum iio_event_type type,
>>>> +                    enum iio_event_direction dir)
>>>> +{
>>>> +
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    return data->ev_enable_state;
>>>> +}
>>>> +
>>>> +static int bmg160_write_event_config(struct iio_dev *indio_dev,
>>>> +                     const struct iio_chan_spec *chan,
>>>> +                     enum iio_event_type type,
>>>> +                     enum iio_event_direction dir,
>>>> +                     int state)
>>>> +{
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int ret;
>>>> +
>>>> +    if (state && data->ev_enable_state)
>>>> +        return 0;
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +
>>>> +    if (!state && data->motion_trigger_on) {
>>>> +        data->ev_enable_state = 0;
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return 0;
>>>> +    }
>>>> +    /*
>>>> +     * We will expect the enable and disable to do operation in
>>>> +     * in reverse order. This will happen here anyway as our
>>>> +     * resume operation uses sync mode runtime pm calls, the
>>>> +     * suspend operation will be delayed by autosuspend delay
>>>> +     * So the disable operation will still happen in reverse of
>>>> +     * enable operation. When runtime pm is disabled the mode
>>>> +     * is always on so sequence doesn't matter
>>>> +     */
>>> Thanks for the detailed comment!
>>>> +    ret = bmg160_set_power_state(data, state);
>>>> +    if (ret < 0) {
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    ret =  bmg160_setup_any_motion_interrupt(data, state);
>>>> +    if (ret < 0) {
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    data->ev_enable_state = state;
>>>> +    mutex_unlock(&data->mutex);
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_validate_trigger(struct iio_dev *indio_dev,
>>>> +                   struct iio_trigger *trig)
>>>> +{
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    if (data->dready_trig != trig && data->motion_trig != trig)
>>>> +        return -EINVAL;
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 400 1000 2000");
>>>> +
>>>> +static IIO_CONST_ATTR(in_anglvel_scale_available,
>>>> +              "0.001065 0.000532 0.000266 0.000133 0.000066");
>>>> +
>>>> +static struct attribute *bmg160_attributes[] = {
>>>> +    &iio_const_attr_sampling_frequency_available.dev_attr.attr,
>>>> +    &iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
>>>> +    NULL,
>>>> +};
>>>> +
>>>> +static const struct attribute_group bmg160_attrs_group = {
>>>> +    .attrs = bmg160_attributes,
>>>> +};
>>>> +
>>>> +static const struct iio_event_spec bmg160_event = {
>>>> +        .type = IIO_EV_TYPE_ROC,
>>>> +        .dir = IIO_EV_DIR_RISING | IIO_EV_DIR_FALLING,
>>>> +        .mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
>>>> +                       BIT(IIO_EV_INFO_ENABLE)
>>>> +};
>>>> +
>>>> +#define BMG160_CHANNEL(_axis) {                    \
>>>> +    .type = IIO_ANGL_VEL,                        \
>>>> +    .modified = 1,                            \
>>>> +    .channel2 = IIO_MOD_##_axis,                    \
>>>> +    .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),            \
>>>> +    .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |        \
>>>> +                    BIT(IIO_CHAN_INFO_SAMP_FREQ),    \
>>>> +    .scan_index = AXIS_##_axis,                    \
>>>> +    .scan_type = {                            \
>>>> +        .sign = 's',                        \
>>>> +        .realbits = 16,                    \
>>>> +        .storagebits = 16,                    \
>>>> +    },                                \
>>>> +    .event_spec = &bmg160_event,                    \
>>>> +    .num_event_specs = 1                        \
>>>> +}
>>>> +
>>>> +static const struct iio_chan_spec bmg160_channels[] = {
>>>> +    {
>>>> +        .type = IIO_TEMP,
>>>> +        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>>>> +                      BIT(IIO_CHAN_INFO_SCALE) |
>>>> +                      BIT(IIO_CHAN_INFO_OFFSET),
>>>> +        .scan_index = -1,
>>>> +    },
>>>> +    BMG160_CHANNEL(X),
>>>> +    BMG160_CHANNEL(Y),
>>>> +    BMG160_CHANNEL(Z),
>>>> +    IIO_CHAN_SOFT_TIMESTAMP(3),
>>>> +};
>>>> +
>>>> +static const struct iio_info bmg160_info = {
>>>> +    .attrs            = &bmg160_attrs_group,
>>>> +    .read_raw        = bmg160_read_raw,
>>>> +    .write_raw        = bmg160_write_raw,
>>>> +    .read_event_value    = bmg160_read_event,
>>>> +    .write_event_value    = bmg160_write_event,
>>>> +    .write_event_config    = bmg160_write_event_config,
>>>> +    .read_event_config    = bmg160_read_event_config,
>>>> +    .validate_trigger    = bmg160_validate_trigger,
>>>> +    .driver_module        = THIS_MODULE,
>>>> +};
>>>> +
>>>> +static irqreturn_t bmg160_trigger_handler(int irq, void *p)
>>>> +{
>>>> +    struct iio_poll_func *pf = p;
>>>> +    struct iio_dev *indio_dev = pf->indio_dev;
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int bit, ret, i = 0;
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +    for_each_set_bit(bit, indio_dev->buffer->scan_mask,
>>>> +             indio_dev->masklength) {
>>>> +        ret = i2c_smbus_read_word_data(data->client,
>>>> +                           BMG160_AXIS_TO_REG(bit));
>>>> +        if (ret < 0) {
>>>> +            mutex_unlock(&data->mutex);
>>>> +            goto err;
>>>> +        }
>>>> +        data->buffer[i++] = ret;
>>>> +    }
>>>> +    mutex_unlock(&data->mutex);
>>>> +
>>>> +    iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
>>>> +                       data->timestamp);
>>>> +err:
>>>> +    iio_trigger_notify_done(indio_dev->trig);
>>>> +
>>>> +    return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +static int bmg160_trig_try_reen(struct iio_trigger *trig)
>>>> +{
>>>> +    struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int ret;
>>>> +
>>>> +    /* new data interrupts don't need ack */
>>>> +    if (data->dready_trigger_on)
>>>> +        return 0;
>>>> +
>>>> +    /* Set latched mode interrupt and clear any latched interrupt */
>>>> +    ret = i2c_smbus_write_byte_data(data->client,
>>>> +                    BMG160_REG_INT_RST_LATCH,
>>>> +                    BMG160_INT_MODE_LATCH_INT |
>>>> +                    BMG160_INT_MODE_LATCH_RESET);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_data_rdy_trigger_set_state(struct iio_trigger *trig,
>>>> +                         bool state)
>>>> +{
>>>> +    struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int ret;
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +
>>>> +    if (!state && data->ev_enable_state && data->motion_trigger_on) {
>>>> +        data->motion_trigger_on = false;
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return 0;
>>>> +    }
>>>> +
>>>> +    /*
>>>> +     * Refer to comment in bmg160_write_event_config for
>>>> +     * enable/disable operation order
>>>> +     */
>>>> +    ret = bmg160_set_power_state(data, state);
>>>> +    if (ret < 0) {
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +    if (data->motion_trig == trig)
>>>> +        ret =  bmg160_setup_any_motion_interrupt(data, state);
>>>> +    else
>>>> +        ret = bmg160_setup_new_data_interrupt(data, state);
>>>> +    if (ret < 0) {
>>>> +        mutex_unlock(&data->mutex);
>>>> +        return ret;
>>>> +    }
>>>> +    if (data->motion_trig == trig)
>>>> +        data->motion_trigger_on = state;
>>>> +    else
>>>> +        data->dready_trigger_on = state;
>>>> +
>>>> +    mutex_unlock(&data->mutex);
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static const struct iio_trigger_ops bmg160_trigger_ops = {
>>>> +    .set_trigger_state = bmg160_data_rdy_trigger_set_state,
>>>> +    .try_reenable = bmg160_trig_try_reen,
>>>> +    .owner = THIS_MODULE,
>>>> +};
>>>> +
>>>> +static irqreturn_t bmg160_event_handler(int irq, void *private)
>>>> +{
>>>> +    struct iio_dev *indio_dev = private;
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int ret;
>>>> +    int dir;
>>>> +
>>>> +    ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_STATUS_2);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&data->client->dev, "Error reading reg_int_status2\n");
>>>> +        goto ack_intr_status;
>>>> +    }
>>>> +
>>>> +    if (ret & 0x08)
>>>> +        dir = IIO_EV_DIR_RISING;
>>>> +    else
>>>> +        dir = IIO_EV_DIR_FALLING;
>>>> +
>>>> +    if (ret & BMG160_ANY_MOTION_MASK)
>>>> +        iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
>>>> +                            0,
>>>> +                            IIO_MOD_X_OR_Y_OR_Z,
>>>> +                            IIO_EV_TYPE_ROC,
>>>> +                            dir),
>>>> +                            data->timestamp);
>>>> +
>>>> +ack_intr_status:
>>>> +    if (!data->dready_trigger_on) {
>>>> +        ret = i2c_smbus_write_byte_data(data->client,
>>>> +                    BMG160_REG_INT_RST_LATCH,
>>>> +                    BMG160_INT_MODE_LATCH_INT |
>>>> +                    BMG160_INT_MODE_LATCH_RESET);
>>>> +        if (ret < 0)
>>>> +            dev_err(&data->client->dev,
>>>> +                "Error writing reg_rst_latch\n");
>>>> +    }
>>>> +
>>>> +    return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +static irqreturn_t bmg160_data_rdy_trig_poll(int irq, void *private)
>>>> +{
>>>> +    struct iio_dev *indio_dev = private;
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    data->timestamp = iio_get_time_ns();
>>>> +
>>>> +    if (data->dready_trigger_on)
>>>> +        iio_trigger_poll(data->dready_trig);
>>>> +    else if (data->motion_trigger_on)
>>>> +        iio_trigger_poll(data->motion_trig);
>>>> +
>>>> +    if (data->ev_enable_state)
>>>> +        return IRQ_WAKE_THREAD;
>>>> +    else
>>>> +        return IRQ_HANDLED;
>>>> +
>>>> +}
>>>> +
>>>> +static int bmg160_acpi_gpio_probe(struct i2c_client *client,
>>>> +                  struct bmg160_data *data)
>>>> +{
>>>> +    const struct acpi_device_id *id;
>>>> +    struct device *dev;
>>>> +    struct gpio_desc *gpio;
>>>> +    int ret;
>>>> +
>>>> +    if (!client)
>>>> +        return -EINVAL;
>>>> +
>>>> +    dev = &client->dev;
>>>> +    if (!ACPI_HANDLE(dev))
>>>> +        return -ENODEV;
>>>> +
>>>> +    id = acpi_match_device(dev->driver->acpi_match_table, dev);
>>>> +    if (!id)
>>>> +        return -ENODEV;
>>>> +
>>>> +    /* data ready gpio interrupt pin */
>>>> +    gpio = devm_gpiod_get_index(dev, BMG160_GPIO_NAME, 0);
>>>> +    if (IS_ERR(gpio)) {
>>>> +        dev_err(dev, "acpi gpio get index failed\n");
>>>> +        return PTR_ERR(gpio);
>>>> +    }
>>>> +
>>>> +    ret = gpiod_direction_input(gpio);
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    ret = gpiod_to_irq(gpio);
>>>> +
>>>> +    dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
>>>> +
>>>> +    return ret;
>>>> +}
>>>> +
>>>> +static int bmg160_probe(struct i2c_client *client,
>>>> +            const struct i2c_device_id *id)
>>>> +{
>>>> +    struct bmg160_data *data;
>>>> +    struct iio_dev *indio_dev;
>>>> +    int ret;
>>>> +
>>>> +    indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>>>> +    if (!indio_dev)
>>>> +        return -ENOMEM;
>>>> +
>>>> +    data = iio_priv(indio_dev);
>>>> +    i2c_set_clientdata(client, indio_dev);
>>>> +    data->client = client;
>>>> +
>>>> +    ret = bmg160_chip_init(data);
>>>> +    if (ret < 0)
>>>> +        return ret;
>>>> +
>>>> +    mutex_init(&data->mutex);
>>>> +
>>>> +    indio_dev->dev.parent = &client->dev;
>>>> +    indio_dev->channels = bmg160_channels;
>>>> +    indio_dev->num_channels = ARRAY_SIZE(bmg160_channels);
>>>> +    indio_dev->name = BMG160_DRV_NAME;
>>>> +    indio_dev->modes = INDIO_DIRECT_MODE;
>>>> +    indio_dev->info = &bmg160_info;
>>>> +
>>>> +    if (client->irq <= 0)
>>>> +        client->irq = bmg160_acpi_gpio_probe(client, data);
>>>> +
>>>> +    if (client->irq > 0) {
>>>> +        ret = devm_request_threaded_irq(&client->dev,
>>>> +                        client->irq,
>>>> +                        bmg160_data_rdy_trig_poll,
>>>> +                        bmg160_event_handler,
>>>> +                        IRQF_TRIGGER_RISING,
>>>> +                        BMG160_IRQ_NAME,
>>>> +                        indio_dev);
>>>> +        if (ret)
>>>> +            return ret;
>>>> +
>>>> +        data->dready_trig = devm_iio_trigger_alloc(&client->dev,
>>>> +                               "%s-dev%d",
>>>> +                               indio_dev->name,
>>>> +                               indio_dev->id);
>>>> +        if (!data->dready_trig)
>>>> +            return -ENOMEM;
>>>> +
>>>> +        data->motion_trig = devm_iio_trigger_alloc(&client->dev,
>>>> +                              "%s-any-motion-dev%d",
>>>> +                              indio_dev->name,
>>>> +                              indio_dev->id);
>>>> +        if (!data->motion_trig)
>>>> +            return -ENOMEM;
>>>> +
>>>> +        data->dready_trig->dev.parent = &client->dev;
>>>> +        data->dready_trig->ops = &bmg160_trigger_ops;
>>>> +        iio_trigger_set_drvdata(data->dready_trig, indio_dev);
>>>> +        ret = iio_trigger_register(data->dready_trig);
>>>> +        if (ret)
>>>> +            return ret;
>>>> +
>>>> +        data->motion_trig->dev.parent = &client->dev;
>>>> +        data->motion_trig->ops = &bmg160_trigger_ops;
>>>> +        iio_trigger_set_drvdata(data->motion_trig, indio_dev);
>>>> +        ret = iio_trigger_register(data->motion_trig);
>>>> +        if (ret) {
>>>> +            data->motion_trig = NULL;
>>>> +            goto err_trigger_unregister;
>>>> +        }
>>>> +
>>>> +        ret = iio_triggered_buffer_setup(indio_dev,
>>>> +                         NULL,
>>>> +                         bmg160_trigger_handler,
>>>> +                         NULL);
>>>> +        if (ret < 0) {
>>>> +            dev_err(&client->dev,
>>>> +                "iio triggered buffer setup failed\n");
>>>> +            goto err_trigger_unregister;
>>>> +        }
>>>> +    }
>>>> +
>>>> +    ret = iio_device_register(indio_dev);
>>>> +    if (ret < 0) {
>>>> +        dev_err(&client->dev, "unable to register iio device\n");
>>>> +        goto err_buffer_cleanup;
>>>> +    }
>>>> +
>>>> +    ret = pm_runtime_set_active(&client->dev);
>>>> +    if (ret)
>>>> +        goto err_iio_unregister;
>>>> +
>>>> +    pm_runtime_enable(&client->dev);
>>>> +    pm_runtime_set_autosuspend_delay(&client->dev,
>>>> +                     BMG160_AUTO_SUSPEND_DELAY_MS);
>>>> +    pm_runtime_use_autosuspend(&client->dev);
>>>> +
>>>> +    return 0;
>>>> +
>>>> +err_iio_unregister:
>>>> +    iio_device_unregister(indio_dev);
>>>> +err_buffer_cleanup:
>>>> +    if (data->dready_trig)
>>>> +        iio_triggered_buffer_cleanup(indio_dev);
>>>> +err_trigger_unregister:
>>>> +    if (data->dready_trig)
>>>> +        iio_trigger_unregister(data->dready_trig);
>>>> +    if (data->motion_trig)
>>>> +        iio_trigger_unregister(data->motion_trig);
>>>> +
>>>> +    return ret;
>>>> +}
>>>> +
>>>> +static int bmg160_remove(struct i2c_client *client)
>>>> +{
>>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(client);
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    pm_runtime_disable(&client->dev);
>>>> +    pm_runtime_set_suspended(&client->dev);
>>>> +    pm_runtime_put_noidle(&client->dev);
>>>> +
>>>> +    iio_device_unregister(indio_dev);
>>>> +
>>>> +    if (data->dready_trig) {
>>>> +        iio_triggered_buffer_cleanup(indio_dev);
>>>> +        iio_trigger_unregister(data->dready_trig);
>>>> +        iio_trigger_unregister(data->motion_trig);
>>>> +    }
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +    bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
>>>> +    mutex_unlock(&data->mutex);
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +#ifdef CONFIG_PM_SLEEP
>>>> +static int bmg160_suspend(struct device *dev)
>>>> +{
>>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +    bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>>>> +    mutex_unlock(&data->mutex);
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static int bmg160_resume(struct device *dev)
>>>> +{
>>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    mutex_lock(&data->mutex);
>>>> +    if (data->dready_trigger_on || data->motion_trigger_on ||
>>>> +                            data->ev_enable_state)
>>>> +        bmg160_set_mode(data, BMG160_MODE_NORMAL);
>>>> +    mutex_unlock(&data->mutex);
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +#endif
>>>> +
>>>> +#ifdef CONFIG_PM_RUNTIME
>>>> +static int bmg160_runtime_suspend(struct device *dev)
>>>> +{
>>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +
>>>> +    return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
>>>> +}
>>>> +
>>>> +static int bmg160_runtime_resume(struct device *dev)
>>>> +{
>>>> +    struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
>>>> +    struct bmg160_data *data = iio_priv(indio_dev);
>>>> +    int ret;
>>>> +
>>>> +    ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
>>>> +    if (ret < 0)
>>>> +        return ret;
>>>> +
>>>> +    msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +#endif
>>>> +
>>>> +static const struct dev_pm_ops bmg160_pm_ops = {
>>>> +    SET_SYSTEM_SLEEP_PM_OPS(bmg160_suspend, bmg160_resume)
>>>> +    SET_RUNTIME_PM_OPS(bmg160_runtime_suspend,
>>>> +               bmg160_runtime_resume, NULL)
>>>> +};
>>>> +
>>>> +static const struct acpi_device_id bmg160_acpi_match[] = {
>>>> +    {"BMG0160", 0},
>>>> +    { },
>>>> +};
>>>> +MODULE_DEVICE_TABLE(acpi, bmg160_acpi_match);
>>>> +
>>>> +static const struct i2c_device_id bmg160_id[] = {
>>>> +    {"bmg160", 0},
>>>> +    {}
>>>> +};
>>>> +
>>>> +MODULE_DEVICE_TABLE(i2c, bmg160_id);
>>>> +
>>>> +static struct i2c_driver bmg160_driver = {
>>>> +    .driver = {
>>>> +        .name    = BMG160_DRV_NAME,
>>>> +        .acpi_match_table = ACPI_PTR(bmg160_acpi_match),
>>>> +        .pm    = &bmg160_pm_ops,
>>>> +    },
>>>> +    .probe        = bmg160_probe,
>>>> +    .remove        = bmg160_remove,
>>>> +    .id_table    = bmg160_id,
>>>> +};
>>>> +module_i2c_driver(bmg160_driver);
>>>> +
>>>> +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
>>>> +MODULE_LICENSE("GPL v2");
>>>> +MODULE_DESCRIPTION("BMG160 Gyro driver");
>>>>
>>>
>>
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