[PATCH] iio: accel: Add driver for dmard10 3-axis Accelerometer

[PATCH] iio: accel: Add driver for dmard10 3-axis Accelerometer

[Hans de Goede]

Add a driver for the Domintech ARD10 3-axis Accelerometer, based on the
android driver found here: https://github.com/domintech/dmard10

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
 drivers/iio/accel/Kconfig                          |  10 +
 drivers/iio/accel/Makefile                         |   1 +
 drivers/iio/accel/dmard10.c                        | 277 +++++++++++++++++++++
 4 files changed, 289 insertions(+)
 create mode 100644 drivers/iio/accel/dmard10.c

diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index fbbad64..21ca02e 100644
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -39,6 +39,7 @@ dallas,ds75		Digital Thermometer and Thermostat
 dlg,da9053		DA9053: flexible system level PMIC with multicore support
 dlg,da9063		DA9063: system PMIC for quad-core application processors
 domintech,dmard09	DMARD09: 3-axis Accelerometer
+domintech,dmard10	DMARD10: 3-axis Accelerometer
 epson,rx8010		I2C-BUS INTERFACE REAL TIME CLOCK MODULE
 epson,rx8025		High-Stability. I2C-Bus INTERFACE REAL TIME CLOCK MODULE
 epson,rx8581		I2C-BUS INTERFACE REAL TIME CLOCK MODULE
diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 3aee97d..b325a3c 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -71,6 +71,16 @@ config DMARD09
 	  Choosing M will build the driver as a module. If so, the module
 	  will be called dmard09.
 
+config DMARD10
+	tristate "Domintech DMARD10 3-axis Accelerometer Driver"
+	depends on I2C
+	help
+	  Say yes here to get support for the Domintech DMARD10 3-axis
+	  accelerometer.
+
+	  Choosing M will build the driver as a module. If so, the module
+	  will be called dmard10.
+
 config HID_SENSOR_ACCEL_3D
 	depends on HID_SENSOR_HUB
 	select IIO_BUFFER
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 07a0c72..9f51559 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_BMC150_ACCEL_I2C) += bmc150-accel-i2c.o
 obj-$(CONFIG_BMC150_ACCEL_SPI) += bmc150-accel-spi.o
 obj-$(CONFIG_DMARD06)	+= dmard06.o
 obj-$(CONFIG_DMARD09)	+= dmard09.o
+obj-$(CONFIG_DMARD10)	+= dmard10.o
 obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
 obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
 obj-$(CONFIG_KXSD9)	+= kxsd9.o
diff --git a/drivers/iio/accel/dmard10.c b/drivers/iio/accel/dmard10.c
new file mode 100644
index 0000000..fc099bd
--- /dev/null
+++ b/drivers/iio/accel/dmard10.c
@@ -0,0 +1,277 @@
+/**
+ * IIO driver for the 3-axis accelerometer Domintech ARD10.
+ *
+ * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
+ * Copyright (c) 2012 Domintech Technology Co., Ltd
+ *
+ * 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.
+ */
+
+#include <asm/unaligned.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define REG_ACTR				0x00
+#define REG_AFEM				0x0c
+#define REG_STADR				0x12
+#define REG_STAINT				0x1c
+#define REG_MISC2				0x1f
+#define REG_PD					0x21
+
+#define MODE_Off				0x00
+#define MODE_Standby				0x02
+#define MODE_Active				0x06
+#define MODE_ReadOTP				0x12
+#define MODE_ResetDataPath			0x82
+
+/* AFEN set 1, ATM[2:0]=b'000(normal), EN_Z/Y/X/T=1 */
+#define VALUE_AFEM_AFEN_Normal			0x8f
+/* ODR[3:0]=b'0111 (100Hz), CCK[3:0]=b'0100 (204.8kHZ) */
+#define VALUE_CKSEL_ODR_100_204			0x74
+/* INTC[6:5]=b'00 */
+#define VALUE_INTC				0x00
+/* TAP1/TAP2 Average 2 */
+#define VALUE_TAPNS_Ave_2			0x11
+
+#define VALUE_STADR				0x55
+#define VALUE_STAINT				0xaa
+#define VALUE_MISC2_OSCA_EN			0x08
+#define VALUE_PD_RST				0x52
+
+/*
+ * a value of + or -128 corresponds to + or - 1G
+ * scale = 1 / 128 = 0.0078125
+ */
+
+#define DMARD10_SCALE_AVAIL		"0.007812500"
+
+static const int dmard10_nscale = 7812500;
+
+#define DMARD10_CHANNEL(reg, axis) {	\
+	.type = IIO_ACCEL,	\
+	.address = reg,	\
+	.modified = 1,	\
+	.channel2 = IIO_MOD_##axis,	\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+}
+
+static const struct iio_chan_spec dmard10_channels[] = {
+	DMARD10_CHANNEL(2, X),
+	DMARD10_CHANNEL(4, Y),
+	DMARD10_CHANNEL(6, Z),
+};
+
+struct dmard10_data {
+	struct i2c_client *client;
+};
+
+static IIO_CONST_ATTR(in_accel_scale_available, DMARD10_SCALE_AVAIL);
+
+static struct attribute *dmard10_attributes[] = {
+	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group dmard10_attribute_group = {
+	.attrs = dmard10_attributes
+};
+
+/* Init sequence taken from the android driver */
+static int dmard10_reset(struct i2c_client *client)
+{
+	unsigned char buffer[7];
+	int ret;
+
+	/* 1. Powerdown reset */
+	buffer[0] = REG_PD;
+	buffer[1] = VALUE_PD_RST;
+	ret = i2c_master_send(client, buffer, 2);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * 2. ACTR => Standby mode => Download OTP to parameter reg =>
+	 *    Standby mode => Reset data path => Standby mode
+	 */
+	buffer[0] = REG_ACTR;
+	buffer[1] = MODE_Standby;
+	buffer[2] = MODE_ReadOTP;
+	buffer[3] = MODE_Standby;
+	buffer[4] = MODE_ResetDataPath;
+	buffer[5] = MODE_Standby;
+	ret = i2c_master_send(client, buffer, 6);
+	if (ret < 0)
+		return ret;
+
+	/* 3. OSCA_EN = 1 ,TSTO = b'000(INT1 = normal, TEST0 = normal) */
+	buffer[0] = REG_MISC2;
+	buffer[1] = VALUE_MISC2_OSCA_EN;
+	ret = i2c_master_send(client, buffer, 2);
+	if (ret < 0)
+		return ret;
+
+	/* 4. AFEN = 1(AFE will powerdown after ADC) */
+	buffer[0] = REG_AFEM;
+	buffer[1] = VALUE_AFEM_AFEN_Normal;
+	buffer[2] = VALUE_CKSEL_ODR_100_204;
+	buffer[3] = VALUE_INTC;
+	buffer[4] = VALUE_TAPNS_Ave_2;
+	buffer[5] = 0x00; /* DLYC, no delay timing */
+	buffer[6] = 0x07; /* INTD=1 push-pull, INTA=1 active high, AUTOT=1 */
+	ret = i2c_master_send(client, buffer, 7);
+	if (ret < 0)
+		return ret;
+
+	/* 5. Activation mode */
+	buffer[0] = REG_ACTR;
+	buffer[1] = MODE_Active;
+	ret = i2c_master_send(client, buffer, 2);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+/* Shutdown sequence taken from the android driver */
+static int dmard10_shutdown(struct i2c_client *client)
+{
+	unsigned char buffer[7];
+
+	buffer[0] = REG_ACTR;
+	buffer[1] = MODE_Standby;
+	buffer[2] = MODE_Off;
+
+	return i2c_master_send(client, buffer, 3);
+}
+
+static int dmard10_read_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan,
+				int *val, int *val2, long mask)
+{
+	struct dmard10_data *data = iio_priv(indio_dev);
+	unsigned char buf[8];
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		/*
+		 * Read 8 bytes starting at the REG_STADR register, trying to
+		 * read the individual X, Y, Z registers will always read 0.
+		 */
+		ret = i2c_smbus_read_i2c_block_data(data->client, REG_STADR,
+						    8, buf);
+		if (ret < 0)
+			return ret;
+		ret = get_unaligned_le16(&buf[chan->address]);
+		*val = sign_extend32(ret, 12);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		*val2 = dmard10_nscale;
+		return IIO_VAL_INT_PLUS_NANO;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info dmard10_info = {
+	.driver_module	= THIS_MODULE,
+	.read_raw	= dmard10_read_raw,
+	.attrs		= &dmard10_attribute_group,
+};
+
+static int dmard10_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	int ret;
+	struct iio_dev *indio_dev;
+	struct dmard10_data *data;
+
+	/* These 2 registers have special POR reset values used for id */
+	ret = i2c_smbus_read_byte_data(client, REG_STADR);
+	if (ret != VALUE_STADR)
+		return (ret < 0) ? ret : -ENODEV;
+
+	ret = i2c_smbus_read_byte_data(client, REG_STAINT);
+	if (ret != VALUE_STAINT)
+		return (ret < 0) ? ret : -ENODEV;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev) {
+		dev_err(&client->dev, "iio allocation failed!\n");
+		return -ENOMEM;
+	}
+
+	data = iio_priv(indio_dev);
+	data->client = client;
+	i2c_set_clientdata(client, indio_dev);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &dmard10_info;
+	indio_dev->name = "dmard10";
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = dmard10_channels;
+	indio_dev->num_channels = ARRAY_SIZE(dmard10_channels);
+
+	ret = dmard10_reset(client);
+	if (ret < 0)
+		return ret;
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&client->dev, "device_register failed\n");
+		dmard10_shutdown(client);
+	}
+
+	return ret;
+}
+
+static int dmard10_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+
+	return dmard10_shutdown(client);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int dmard10_suspend(struct device *dev)
+{
+	return dmard10_shutdown(to_i2c_client(dev));
+}
+
+static int dmard10_resume(struct device *dev)
+{
+	return dmard10_reset(to_i2c_client(dev));
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(dmard10_pm_ops, dmard10_suspend, dmard10_resume);
+
+static const struct i2c_device_id dmard10_i2c_id[] = {
+	{"dmard10", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, dmard10_i2c_id);
+
+static struct i2c_driver dmard10_driver = {
+	.driver = {
+		.name = "dmard10",
+		.pm = &dmard10_pm_ops,
+	},
+	.probe		= dmard10_probe,
+	.remove		= dmard10_remove,
+	.id_table	= dmard10_i2c_id,
+};
+
+module_i2c_driver(dmard10_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_DESCRIPTION("Domintech ARD10 3-Axis Accelerometer driver");
+MODULE_LICENSE("GPL v2");
-- 
2.9.3

Re: [PATCH] iio: accel: Add driver for dmard10 3-axis Accelerometer

[Peter Meerwald-Stadler]

> Add a driver for the Domintech ARD10 3-axis Accelerometer, based on the
> android driver found here: https://github.com/domintech/dmard10

needs some cleanup
 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
>  drivers/iio/accel/Kconfig                          |  10 +
>  drivers/iio/accel/Makefile                         |   1 +
>  drivers/iio/accel/dmard10.c                        | 277 +++++++++++++++++++++
>  4 files changed, 289 insertions(+)
>  create mode 100644 drivers/iio/accel/dmard10.c
> 
> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> index fbbad64..21ca02e 100644
> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> @@ -39,6 +39,7 @@ dallas,ds75		Digital Thermometer and Thermostat
>  dlg,da9053		DA9053: flexible system level PMIC with multicore support
>  dlg,da9063		DA9063: system PMIC for quad-core application processors
>  domintech,dmard09	DMARD09: 3-axis Accelerometer
> +domintech,dmard10	DMARD10: 3-axis Accelerometer
>  epson,rx8010		I2C-BUS INTERFACE REAL TIME CLOCK MODULE
>  epson,rx8025		High-Stability. I2C-Bus INTERFACE REAL TIME CLOCK MODULE
>  epson,rx8581		I2C-BUS INTERFACE REAL TIME CLOCK MODULE
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index 3aee97d..b325a3c 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -71,6 +71,16 @@ config DMARD09
>  	  Choosing M will build the driver as a module. If so, the module
>  	  will be called dmard09.
>  
> +config DMARD10
> +	tristate "Domintech DMARD10 3-axis Accelerometer Driver"
> +	depends on I2C
> +	help
> +	  Say yes here to get support for the Domintech DMARD10 3-axis
> +	  accelerometer.
> +
> +	  Choosing M will build the driver as a module. If so, the module
> +	  will be called dmard10.
> +
>  config HID_SENSOR_ACCEL_3D
>  	depends on HID_SENSOR_HUB
>  	select IIO_BUFFER
> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> index 07a0c72..9f51559 100644
> --- a/drivers/iio/accel/Makefile
> +++ b/drivers/iio/accel/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_BMC150_ACCEL_I2C) += bmc150-accel-i2c.o
>  obj-$(CONFIG_BMC150_ACCEL_SPI) += bmc150-accel-spi.o
>  obj-$(CONFIG_DMARD06)	+= dmard06.o
>  obj-$(CONFIG_DMARD09)	+= dmard09.o
> +obj-$(CONFIG_DMARD10)	+= dmard10.o
>  obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
>  obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
>  obj-$(CONFIG_KXSD9)	+= kxsd9.o
> diff --git a/drivers/iio/accel/dmard10.c b/drivers/iio/accel/dmard10.c
> new file mode 100644
> index 0000000..fc099bd
> --- /dev/null
> +++ b/drivers/iio/accel/dmard10.c
> @@ -0,0 +1,277 @@
> +/**
> + * IIO driver for the 3-axis accelerometer Domintech ARD10.
> + *
> + * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
> + * Copyright (c) 2012 Domintech Technology Co., Ltd
> + *
> + * 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.
> + */
> +
> +#include <asm/unaligned.h>
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define REG_ACTR				0x00

DMARD10_ prefix please

> +#define REG_AFEM				0x0c
> +#define REG_STADR				0x12
> +#define REG_STAINT				0x1c
> +#define REG_MISC2				0x1f
> +#define REG_PD					0x21
> +
> +#define MODE_Off				0x00

UPPERCASE these

> +#define MODE_Standby				0x02
> +#define MODE_Active				0x06
> +#define MODE_ReadOTP				0x12
> +#define MODE_ResetDataPath			0x82
> +
> +/* AFEN set 1, ATM[2:0]=b'000(normal), EN_Z/Y/X/T=1 */
> +#define VALUE_AFEM_AFEN_Normal			0x8f
> +/* ODR[3:0]=b'0111 (100Hz), CCK[3:0]=b'0100 (204.8kHZ) */
> +#define VALUE_CKSEL_ODR_100_204			0x74
> +/* INTC[6:5]=b'00 */
> +#define VALUE_INTC				0x00
> +/* TAP1/TAP2 Average 2 */
> +#define VALUE_TAPNS_Ave_2			0x11
> +
> +#define VALUE_STADR				0x55
> +#define VALUE_STAINT				0xaa
> +#define VALUE_MISC2_OSCA_EN			0x08
> +#define VALUE_PD_RST				0x52
> +
> +/*
> + * a value of + or -128 corresponds to + or - 1G
> + * scale = 1 / 128 = 0.0078125
> + */
> +
> +#define DMARD10_SCALE_AVAIL		"0.007812500"
> +
> +static const int dmard10_nscale = 7812500;
> +
> +#define DMARD10_CHANNEL(reg, axis) {	\
> +	.type = IIO_ACCEL,	\
> +	.address = reg,	\
> +	.modified = 1,	\
> +	.channel2 = IIO_MOD_##axis,	\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
> +}
> +
> +static const struct iio_chan_spec dmard10_channels[] = {
> +	DMARD10_CHANNEL(2, X),

can we have proper #defines for the register addresses please? actually 
they seem to be offsets or indices into the buffer (worth a comment)

> +	DMARD10_CHANNEL(4, Y),
> +	DMARD10_CHANNEL(6, Z),
> +};
> +
> +struct dmard10_data {
> +	struct i2c_client *client;
> +};
> +
> +static IIO_CONST_ATTR(in_accel_scale_available, DMARD10_SCALE_AVAIL);
> +
> +static struct attribute *dmard10_attributes[] = {
> +	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group dmard10_attribute_group = {
> +	.attrs = dmard10_attributes
> +};
> +
> +/* Init sequence taken from the android driver */
> +static int dmard10_reset(struct i2c_client *client)
> +{
> +	unsigned char buffer[7];
> +	int ret;
> +
> +	/* 1. Powerdown reset */
> +	buffer[0] = REG_PD;
> +	buffer[1] = VALUE_PD_RST;
> +	ret = i2c_master_send(client, buffer, 2);

can't we just use i2c_smbus_write_byte_data()?

> +	if (ret < 0)
> +		return ret;
> +
> +	/*
> +	 * 2. ACTR => Standby mode => Download OTP to parameter reg =>
> +	 *    Standby mode => Reset data path => Standby mode
> +	 */
> +	buffer[0] = REG_ACTR;
> +	buffer[1] = MODE_Standby;
> +	buffer[2] = MODE_ReadOTP;
> +	buffer[3] = MODE_Standby;
> +	buffer[4] = MODE_ResetDataPath;
> +	buffer[5] = MODE_Standby;
> +	ret = i2c_master_send(client, buffer, 6);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* 3. OSCA_EN = 1 ,TSTO = b'000(INT1 = normal, TEST0 = normal) */

comments could use some typographic love (space after comma not before, 
space after pharenthesis)

> +	buffer[0] = REG_MISC2;
> +	buffer[1] = VALUE_MISC2_OSCA_EN;
> +	ret = i2c_master_send(client, buffer, 2);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* 4. AFEN = 1(AFE will powerdown after ADC) */
> +	buffer[0] = REG_AFEM;
> +	buffer[1] = VALUE_AFEM_AFEN_Normal;
> +	buffer[2] = VALUE_CKSEL_ODR_100_204;
> +	buffer[3] = VALUE_INTC;
> +	buffer[4] = VALUE_TAPNS_Ave_2;
> +	buffer[5] = 0x00; /* DLYC, no delay timing */
> +	buffer[6] = 0x07; /* INTD=1 push-pull, INTA=1 active high, AUTOT=1 */
> +	ret = i2c_master_send(client, buffer, 7);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* 5. Activation mode */
> +	buffer[0] = REG_ACTR;
> +	buffer[1] = MODE_Active;
> +	ret = i2c_master_send(client, buffer, 2);
> +	if (ret < 0)
> +		return ret;

just return

> +
> +	return 0;
> +}
> +
> +/* Shutdown sequence taken from the android driver */
> +static int dmard10_shutdown(struct i2c_client *client)
> +{
> +	unsigned char buffer[7];

buffer too big

> +
> +	buffer[0] = REG_ACTR;
> +	buffer[1] = MODE_Standby;
> +	buffer[2] = MODE_Off;
> +
> +	return i2c_master_send(client, buffer, 3);
> +}
> +
> +static int dmard10_read_raw(struct iio_dev *indio_dev,
> +				struct iio_chan_spec const *chan,
> +				int *val, int *val2, long mask)
> +{
> +	struct dmard10_data *data = iio_priv(indio_dev);
> +	unsigned char buf[8];

__le16 buf[4]

> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		/*
> +		 * Read 8 bytes starting at the REG_STADR register, trying to
> +		 * read the individual X, Y, Z registers will always read 0.
> +		 */
> +		ret = i2c_smbus_read_i2c_block_data(data->client, REG_STADR,
> +						    8, buf);

sizeof(buf)

> +		if (ret < 0)
> +			return ret;
> +		ret = get_unaligned_le16(&buf[chan->address]);
> +		*val = sign_extend32(ret, 12);
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = 0;
> +		*val2 = dmard10_nscale;
> +		return IIO_VAL_INT_PLUS_NANO;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static const struct iio_info dmard10_info = {
> +	.driver_module	= THIS_MODULE,
> +	.read_raw	= dmard10_read_raw,
> +	.attrs		= &dmard10_attribute_group,
> +};
> +
> +static int dmard10_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	int ret;
> +	struct iio_dev *indio_dev;
> +	struct dmard10_data *data;
> +
> +	/* These 2 registers have special POR reset values used for id */
> +	ret = i2c_smbus_read_byte_data(client, REG_STADR);
> +	if (ret != VALUE_STADR)
> +		return (ret < 0) ? ret : -ENODEV;
> +
> +	ret = i2c_smbus_read_byte_data(client, REG_STAINT);
> +	if (ret != VALUE_STAINT)
> +		return (ret < 0) ? ret : -ENODEV;
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> +	if (!indio_dev) {
> +		dev_err(&client->dev, "iio allocation failed!\n");
> +		return -ENOMEM;
> +	}
> +
> +	data = iio_priv(indio_dev);
> +	data->client = client;
> +	i2c_set_clientdata(client, indio_dev);
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &dmard10_info;
> +	indio_dev->name = "dmard10";
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->channels = dmard10_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(dmard10_channels);
> +
> +	ret = dmard10_reset(client);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "device_register failed\n");
> +		dmard10_shutdown(client);
> +	}
> +
> +	return ret;
> +}
> +
> +static int dmard10_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	iio_device_unregister(indio_dev);
> +
> +	return dmard10_shutdown(client);
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int dmard10_suspend(struct device *dev)
> +{
> +	return dmard10_shutdown(to_i2c_client(dev));
> +}
> +
> +static int dmard10_resume(struct device *dev)
> +{
> +	return dmard10_reset(to_i2c_client(dev));
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(dmard10_pm_ops, dmard10_suspend, dmard10_resume);
> +
> +static const struct i2c_device_id dmard10_i2c_id[] = {
> +	{"dmard10", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, dmard10_i2c_id);
> +
> +static struct i2c_driver dmard10_driver = {
> +	.driver = {
> +		.name = "dmard10",
> +		.pm = &dmard10_pm_ops,
> +	},
> +	.probe		= dmard10_probe,
> +	.remove		= dmard10_remove,
> +	.id_table	= dmard10_i2c_id,
> +};
> +
> +module_i2c_driver(dmard10_driver);
> +
> +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
> +MODULE_DESCRIPTION("Domintech ARD10 3-Axis Accelerometer driver");
> +MODULE_LICENSE("GPL v2");
> 

-- 

Peter Meerwald-Stadler
+43-664-2444418 (mobile)

Re: [PATCH] iio: accel: Add driver for dmard10 3-axis Accelerometer

[Hans de Goede]

Hi,

On 12-09-16 10:03, Peter Meerwald-Stadler wrote:
>
>> Add a driver for the Domintech ARD10 3-axis Accelerometer, based on the
>> android driver found here: https://github.com/domintech/dmard10
>
> needs some cleanup

Ok.

<snip>

>> +/* Init sequence taken from the android driver */
>> +static int dmard10_reset(struct i2c_client *client)
>> +{
>> +	unsigned char buffer[7];
>> +	int ret;
>> +
>> +	/* 1. Powerdown reset */
>> +	buffer[0] = REG_PD;
>> +	buffer[1] = VALUE_PD_RST;
>> +	ret = i2c_master_send(client, buffer, 2);
>
> can't we just use i2c_smbus_write_byte_data()?
>
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/*
>> +	 * 2. ACTR => Standby mode => Download OTP to parameter reg =>
>> +	 *    Standby mode => Reset data path => Standby mode
>> +	 */
>> +	buffer[0] = REG_ACTR;
>> +	buffer[1] = MODE_Standby;
>> +	buffer[2] = MODE_ReadOTP;
>> +	buffer[3] = MODE_Standby;
>> +	buffer[4] = MODE_ResetDataPath;
>> +	buffer[5] = MODE_Standby;
>> +	ret = i2c_master_send(client, buffer, 6);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* 3. OSCA_EN = 1 ,TSTO = b'000(INT1 = normal, TEST0 = normal) */
>
> comments could use some typographic love (space after comma not before,
> space after pharenthesis)
>
>> +	buffer[0] = REG_MISC2;
>> +	buffer[1] = VALUE_MISC2_OSCA_EN;
>> +	ret = i2c_master_send(client, buffer, 2);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* 4. AFEN = 1(AFE will powerdown after ADC) */
>> +	buffer[0] = REG_AFEM;
>> +	buffer[1] = VALUE_AFEM_AFEN_Normal;
>> +	buffer[2] = VALUE_CKSEL_ODR_100_204;
>> +	buffer[3] = VALUE_INTC;
>> +	buffer[4] = VALUE_TAPNS_Ave_2;
>> +	buffer[5] = 0x00; /* DLYC, no delay timing */
>> +	buffer[6] = 0x07; /* INTD=1 push-pull, INTA=1 active high, AUTOT=1 */
>> +	ret = i2c_master_send(client, buffer, 7);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* 5. Activation mode */
>> +	buffer[0] = REG_ACTR;
>> +	buffer[1] = MODE_Active;
>> +	ret = i2c_master_send(client, buffer, 2);
>> +	if (ret < 0)
>> +		return ret;
>
> just return

I would prefer not to, that will make the diff
for adding an other step to the reset sequence
a bit messy, more importantly, there is a clear
structure / flow to this function and your suggested
change would break that.

I agree with all your other comments, and I'll do
a v2 fixing them.

Regards,

Hans



>
>> +
>> +	return 0;
>> +}
>> +
>> +/* Shutdown sequence taken from the android driver */
>> +static int dmard10_shutdown(struct i2c_client *client)
>> +{
>> +	unsigned char buffer[7];
>
> buffer too big
>
>> +
>> +	buffer[0] = REG_ACTR;
>> +	buffer[1] = MODE_Standby;
>> +	buffer[2] = MODE_Off;
>> +
>> +	return i2c_master_send(client, buffer, 3);
>> +}
>> +
>> +static int dmard10_read_raw(struct iio_dev *indio_dev,
>> +				struct iio_chan_spec const *chan,
>> +				int *val, int *val2, long mask)
>> +{
>> +	struct dmard10_data *data = iio_priv(indio_dev);
>> +	unsigned char buf[8];
>
> __le16 buf[4]
>
>> +	int ret;
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_RAW:
>> +		/*
>> +		 * Read 8 bytes starting at the REG_STADR register, trying to
>> +		 * read the individual X, Y, Z registers will always read 0.
>> +		 */
>> +		ret = i2c_smbus_read_i2c_block_data(data->client, REG_STADR,
>> +						    8, buf);
>
> sizeof(buf)
>
>> +		if (ret < 0)
>> +			return ret;
>> +		ret = get_unaligned_le16(&buf[chan->address]);
>> +		*val = sign_extend32(ret, 12);
>> +		return IIO_VAL_INT;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		*val = 0;
>> +		*val2 = dmard10_nscale;
>> +		return IIO_VAL_INT_PLUS_NANO;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +}
>> +
>> +static const struct iio_info dmard10_info = {
>> +	.driver_module	= THIS_MODULE,
>> +	.read_raw	= dmard10_read_raw,
>> +	.attrs		= &dmard10_attribute_group,
>> +};
>> +
>> +static int dmard10_probe(struct i2c_client *client,
>> +			const struct i2c_device_id *id)
>> +{
>> +	int ret;
>> +	struct iio_dev *indio_dev;
>> +	struct dmard10_data *data;
>> +
>> +	/* These 2 registers have special POR reset values used for id */
>> +	ret = i2c_smbus_read_byte_data(client, REG_STADR);
>> +	if (ret != VALUE_STADR)
>> +		return (ret < 0) ? ret : -ENODEV;
>> +
>> +	ret = i2c_smbus_read_byte_data(client, REG_STAINT);
>> +	if (ret != VALUE_STAINT)
>> +		return (ret < 0) ? ret : -ENODEV;
>> +
>> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>> +	if (!indio_dev) {
>> +		dev_err(&client->dev, "iio allocation failed!\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	data = iio_priv(indio_dev);
>> +	data->client = client;
>> +	i2c_set_clientdata(client, indio_dev);
>> +
>> +	indio_dev->dev.parent = &client->dev;
>> +	indio_dev->info = &dmard10_info;
>> +	indio_dev->name = "dmard10";
>> +	indio_dev->modes = INDIO_DIRECT_MODE;
>> +	indio_dev->channels = dmard10_channels;
>> +	indio_dev->num_channels = ARRAY_SIZE(dmard10_channels);
>> +
>> +	ret = dmard10_reset(client);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	ret = iio_device_register(indio_dev);
>> +	if (ret < 0) {
>> +		dev_err(&client->dev, "device_register failed\n");
>> +		dmard10_shutdown(client);
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>> +static int dmard10_remove(struct i2c_client *client)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>> +
>> +	iio_device_unregister(indio_dev);
>> +
>> +	return dmard10_shutdown(client);
>> +}
>> +
>> +#ifdef CONFIG_PM_SLEEP
>> +static int dmard10_suspend(struct device *dev)
>> +{
>> +	return dmard10_shutdown(to_i2c_client(dev));
>> +}
>> +
>> +static int dmard10_resume(struct device *dev)
>> +{
>> +	return dmard10_reset(to_i2c_client(dev));
>> +}
>> +#endif
>> +
>> +static SIMPLE_DEV_PM_OPS(dmard10_pm_ops, dmard10_suspend, dmard10_resume);
>> +
>> +static const struct i2c_device_id dmard10_i2c_id[] = {
>> +	{"dmard10", 0},
>> +	{}
>> +};
>> +MODULE_DEVICE_TABLE(i2c, dmard10_i2c_id);
>> +
>> +static struct i2c_driver dmard10_driver = {
>> +	.driver = {
>> +		.name = "dmard10",
>> +		.pm = &dmard10_pm_ops,
>> +	},
>> +	.probe		= dmard10_probe,
>> +	.remove		= dmard10_remove,
>> +	.id_table	= dmard10_i2c_id,
>> +};
>> +
>> +module_i2c_driver(dmard10_driver);
>> +
>> +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
>> +MODULE_DESCRIPTION("Domintech ARD10 3-Axis Accelerometer driver");
>> +MODULE_LICENSE("GPL v2");
>>
>