[PATCH v2] iio: light: Add support for ROHM RPR0521 sensor

Daniel Baluta
2015-05-28T10:52:34Z

This patch adds support for ROHM RPR0521 ambient light and proximity
sensor. It offers raw readings for intensity and proximity.

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
---
Changes since v1: (after Jonathan's review)
* add static const to some structures
* make some local functions static
* added clarification for set_power_state function.

drivers/iio/light/Kconfig | 11 +
drivers/iio/light/Makefile | 1 +
drivers/iio/light/rpr0521.c | 596 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 608 insertions(+)
create mode 100644 drivers/iio/light/rpr0521.c

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index e6198b7..cbc4677 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -168,6 +168,17 @@ config JSA1212
To compile this driver as a module, choose M here:
the module will be called jsa1212.

+config RPR0521
+ tristate "ROHM RPR0521 ALS and proximity sensor driver"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ Say Y here if you want to build support for ROHM's RPR0521
+ ambient light and proximity sensor device.
+
+ To compile this driver as a module, choose M here:
+ the module will be called rpr0521.
+
config SENSORS_LM3533
tristate "LM3533 ambient light sensor"
depends on MFD_LM3533
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index e2d50fd..66fc2fd 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_HID_SENSOR_ALS) += hid-sensor-als.o
obj-$(CONFIG_HID_SENSOR_PROX) += hid-sensor-prox.o
obj-$(CONFIG_ISL29125) += isl29125.o
obj-$(CONFIG_JSA1212) += jsa1212.o
+obj-$(CONFIG_RPR0521) += rpr0521.o
obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o
obj-$(CONFIG_LTR501) += ltr501.o
obj-$(CONFIG_SENSORS_TSL2563) += tsl2563.o
diff --git a/drivers/iio/light/rpr0521.c b/drivers/iio/light/rpr0521.c
new file mode 100644
index 0000000..45d4df5
--- /dev/null
+++ b/drivers/iio/light/rpr0521.c
@@ -0,0 +1,596 @@
+/*
+ * RPR-0521 ROHM Ambient Light and Proximity Sensor
+ *
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * IIO driver for RPR-0521RS (7-bit I2C slave address 0x38).
+ *
+ * TODO: illuminance channel, PM support, buffer
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/delay.h>
+#include <linux/acpi.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/pm_runtime.h>
+
+#define RPR0521_REG_SYSTEM_CTRL 0x40
+#define RPR0521_REG_MODE_CTRL 0x41
+#define RPR0521_REG_ALS_CTRL 0x42
+#define RPR0521_REG_PXS_CTRL 0x43
+#define RPR0521_REG_PXS_DATA 0x44 /* 16-bit, little endian */
+#define RPR0521_REG_ALS_DATA0 0x46 /* 16-bit, little endian */
+#define RPR0521_REG_ALS_DATA1 0x48 /* 16-bit, little endian */
+#define RPR0521_REG_ID 0x92
+
+#define RPR0521_MODE_ALS_MASK BIT(7)
+#define RPR0521_MODE_PXS_MASK BIT(6)
+#define RPR0521_MODE_MEAS_TIME_MASK GENMASK(3, 0)
+#define RPR0521_ALS_DATA0_GAIN_MASK (BIT(4) | BIT(5))
+#define RPR0521_ALS_DATA0_GAIN_SHIFT 4
+#define RPR0521_ALS_DATA1_GAIN_MASK (BIT(2) | BIT(3))
+#define RPR0521_ALS_DATA1_GAIN_SHIFT 2
+#define RPR0521_PXS_GAIN_MASK (BIT(4) | BIT(5))
+#define RPR0521_PXS_GAIN_SHIFT 4
+
+#define RPR0521_MODE_ALS_ENABLE BIT(7)
+#define RPR0521_MODE_ALS_DISABLE 0x00
+#define RPR0521_MODE_PXS_ENABLE BIT(6)
+#define RPR0521_MODE_PXS_DISABLE 0x00
+
+#define RPR0521_PXS_MAX_VAL (BIT(13) - 1)
+#define RPR0521_MANUFACT_ID 0xE0
+#define RPR0521_DEFAULT_MEAS_TIME 0x06 /* ALS - 100ms, PXS - 100ms */
+
+#define RPR0521_DRV_NAME "RPR0521"
+#define RPR0521_REGMAP_NAME "rpr0521_regmap"
+
+#define RPR0521_SLEEP_DELAY_MS 2000
+
+static const int rpr0521_als_gain[4] = {1, 2, 64, 128};
+static const int rpr0521_pxs_gain[3] = {1, 2, 4};
+
+enum rpr0521_channel {
+ RPR0521_CHAN_ALS_DATA0,
+ RPR0521_CHAN_ALS_DATA1,
+ RPR0521_CHAN_PXS,
+};
+
+static const int rpr0521_data_reg[] = {
+ [RPR0521_CHAN_ALS_DATA0] = RPR0521_REG_ALS_DATA0,
+ [RPR0521_CHAN_ALS_DATA1] = RPR0521_REG_ALS_DATA1,
+ [RPR0521_CHAN_PXS] = RPR0521_REG_PXS_DATA,
+};
+
+static const struct rpr0521_gain_info {
+ u8 reg;
+ u8 mask;
+ u8 shift;
+ int *gain;
+ int size;
+} rpr0521_gain[] = {
+ [RPR0521_CHAN_ALS_DATA0] = {
+ .reg = RPR0521_REG_ALS_CTRL,
+ .mask = RPR0521_ALS_DATA0_GAIN_MASK,
+ .shift = RPR0521_ALS_DATA0_GAIN_SHIFT,
+ .gain = (int *)rpr0521_als_gain,
+ .size = ARRAY_SIZE(rpr0521_als_gain),
+ },
+ [RPR0521_CHAN_ALS_DATA1] = {
+ .reg = RPR0521_REG_ALS_CTRL,
+ .mask = RPR0521_ALS_DATA1_GAIN_MASK,
+ .shift = RPR0521_ALS_DATA1_GAIN_SHIFT,
+ .gain = (int *)rpr0521_als_gain,
+ .size = ARRAY_SIZE(rpr0521_als_gain),
+ },
+ [RPR0521_CHAN_PXS] = {
+ .reg = RPR0521_REG_PXS_CTRL,
+ .mask = RPR0521_PXS_GAIN_MASK,
+ .shift = RPR0521_PXS_GAIN_SHIFT,
+ .gain = (int *)rpr0521_pxs_gain,
+ .size = ARRAY_SIZE(rpr0521_pxs_gain),
+ },
+};
+
+struct rpr0521_data {
+ struct i2c_client *client;
+
+ /* protect device params updates (e.g state, gain) */
+ struct mutex lock;
+
+ /* device active status */
+ bool als_dev_en;
+ bool pxs_dev_en;
+
+ /* optimize runtime pm ops - enable device only if needed */
+ bool als_ps_need_en;
+ bool pxs_ps_need_en;
+
+ struct regmap *regmap;
+};
+
+static const struct iio_chan_spec rpr0521_channels[] = {
+ {
+ .type = IIO_INTENSITY,
+ .modified = 1,
+ .address = RPR0521_CHAN_ALS_DATA0,
+ .channel2 = IIO_MOD_LIGHT_BOTH,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_CALIBSCALE),
+ },
+ {
+ .type = IIO_INTENSITY,
+ .modified = 1,
+ .address = RPR0521_CHAN_ALS_DATA1,
+ .channel2 = IIO_MOD_LIGHT_IR,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_CALIBSCALE),
+ },
+ {
+ .type = IIO_PROXIMITY,
+ .address = RPR0521_CHAN_PXS,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_CALIBSCALE),
+ }
+};
+
+static int rpr0521_als_enable(struct rpr0521_data *data, u8 status)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_ALS_MASK,
+ status);
+ if (ret < 0)
+ return ret;
+
+ data->als_dev_en = true;
+
+ return 0;
+}
+
+static int rpr0521_pxs_enable(struct rpr0521_data *data, u8 status)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_PXS_MASK,
+ status);
+ if (ret < 0)
+ return ret;
+
+ data->pxs_dev_en = true;
+
+ return 0;
+}
+
+/**
+ * rpr0521_set_power_state - handles runtime PM state and sensors enabled status
+ *
+ * @data: rpr0521 device private data
+ * @on: state to be set for devices in @device_mask
+ * @device_mask: bitmask specifying for which device we need to update @on state
+ *
+ * We rely on rpr0521_runtime_resume to enable our @device_mask devices, but
+ * if (for example) PXS was enabled (pxs_dev_en = true) by a previous call to
+ * rpr0521_runtime_resume and we want to enable ALS we MUST set ALS enable
+ * bit of RPR0521_REG_MODE_CTRL here because rpr0521_runtime_resume will not
+ * be called twice.
+ */
+static int rpr0521_set_power_state(struct rpr0521_data *data, bool on,
+ u8 device_mask)
+{
+#ifdef CONFIG_PM
+ int ret;
+ u8 update_mask = 0;
+
+ if (device_mask & RPR0521_MODE_ALS_MASK) {
+ if (on && !data->als_ps_need_en && data->pxs_dev_en)
+ update_mask |= RPR0521_MODE_ALS_MASK;
+ else
+ data->als_ps_need_en = on;
+ }
+
+ if (device_mask & RPR0521_MODE_PXS_MASK) {
+ if (on && !data->pxs_ps_need_en && data->als_dev_en)
+ update_mask |= RPR0521_MODE_PXS_MASK;
+ else
+ data->pxs_ps_need_en = on;
+ }
+
+ if (update_mask) {
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ update_mask, update_mask);
+ if (ret < 0)
+ return 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: rpr0521_set_power_state for %d, ret %d\n",
+ on, ret);
+ if (on)
+ pm_runtime_put_noidle(&data->client->dev);
+
+ return ret;
+ }
+#endif
+ return 0;
+}
+
+static int rpr0521_get_gain_index(int *gainv, int size, int gain)
+{
+ int i;
+
+ for (i = 0; i < size; i++)
+ if (gain == gainv[i])
+ return i;
+
+ return -EINVAL;
+}
+
+static int rpr0521_get_gain(struct rpr0521_data *data, int chan, int *val)
+{
+ int ret, reg, idx;
+
+ ret = regmap_read(data->regmap, rpr0521_gain[chan].reg, &reg);
+ if (ret < 0)
+ return ret;
+
+ idx = (rpr0521_gain[chan].mask & reg) >> rpr0521_gain[chan].shift;
+ *val = rpr0521_gain[chan].gain[idx];
+
+ return 0;
+}
+
+static int rpr0521_set_gain(struct rpr0521_data *data, int chan, int val)
+{
+ int idx;
+
+ idx = rpr0521_get_gain_index(rpr0521_gain[chan].gain,
+ rpr0521_gain[chan].size, val);
+ if (idx < 0)
+ return idx;
+
+ return regmap_update_bits(data->regmap, rpr0521_gain[chan].reg,
+ rpr0521_gain[chan].mask,
+ idx << rpr0521_gain[chan].shift);
+}
+
+static int rpr0521_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+ u8 device_mask;
+ __le16 raw_data;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (chan->type) {
+ case IIO_INTENSITY:
+ device_mask = RPR0521_MODE_ALS_MASK;
+ break;
+ case IIO_PROXIMITY:
+ device_mask = RPR0521_MODE_PXS_MASK;
+ break;
+ default:
+ return -EINVAL;
+ }
+ mutex_lock(&data->lock);
+ ret = rpr0521_set_power_state(data, true, device_mask);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ ret = regmap_bulk_read(data->regmap,
+ rpr0521_data_reg[chan->address],
+ &raw_data, 2);
+ if (ret < 0) {
+ rpr0521_set_power_state(data, false, device_mask);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ ret = rpr0521_set_power_state(data, false, device_mask);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+
+ *val = le16_to_cpu(raw_data);
+ /*
+ * proximity uses 12 bits, with bits 7:4 of PXS MSB DATA
+ * being always zero. Also, proximity MUST be exposed as
+ * a distance with lower values for closer objects.
+ */
+ if (chan->type == IIO_PROXIMITY)
+ *val = RPR0521_PXS_MAX_VAL - *val;
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ mutex_lock(&data->lock);
+ ret = rpr0521_get_gain(data, chan->address, val);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int rpr0521_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_CALIBSCALE:
+ mutex_lock(&data->lock);
+ ret = rpr0521_set_gain(data, chan->address, val);
+ mutex_unlock(&data->lock);
+
+ return ret;
+ default:
+ return -EINVAL;
+ }
+}
+
+static IIO_CONST_ATTR(in_intensity_calibscale_available, "1 2 64 128");
+static IIO_CONST_ATTR(in_proximity_calibscale_available, "1 2 4");
+
+static struct attribute *rpr0521_attributes[] = {
+ &iio_const_attr_in_intensity_calibscale_available.dev_attr.attr,
+ &iio_const_attr_in_proximity_calibscale_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group rpr0521_attribute_group = {
+ .attrs = rpr0521_attributes,
+};
+
+static const struct iio_info rpr0521_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = rpr0521_read_raw,
+ .write_raw = rpr0521_write_raw,
+ .attrs = &rpr0521_attribute_group,
+};
+
+static int rpr0521_init(struct rpr0521_data *data)
+{
+ int ret;
+ int id;
+
+ ret = regmap_read(data->regmap, RPR0521_REG_ID, &id);
+ if (ret < 0) {
+ dev_err(&data->client->dev, "Failed to read REG_ID register\n");
+ return ret;
+ }
+
+ if (id != RPR0521_MANUFACT_ID) {
+ dev_err(&data->client->dev, "Wrong id, got %x expected %x\n",
+ id, RPR0521_MANUFACT_ID);
+ return -ENODEV;
+ }
+
+ /* set default measurement time - 100 ms for both ALS and PS */
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_MEAS_TIME_MASK,
+ RPR0521_DEFAULT_MEAS_TIME);
+ if (ret) {
+ pr_err("regmap_update bits returned %d\n", ret);
+ return ret;
+ }
+
+ ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
+ if (ret < 0)
+ return ret;
+ ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int rpr0521_poweroff(struct rpr0521_data *data)
+{
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
+ RPR0521_MODE_ALS_MASK |
+ RPR0521_MODE_PXS_MASK,
+ 0x00);
+ if (ret < 0)
+ return ret;
+
+ data->als_dev_en = false;
+ data->pxs_dev_en = false;
+
+ return 0;
+}
+
+static bool rpr0521_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case RPR0521_REG_MODE_CTRL:
+ case RPR0521_REG_ALS_CTRL:
+ case RPR0521_REG_PXS_CTRL:
+ return false;
+ default:
+ return true;
+ }
+}
+
+static const struct regmap_config rpr0521_regmap_config = {
+ .name = RPR0521_REGMAP_NAME,
+
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .max_register = RPR0521_REG_ID,
+ .cache_type = REGCACHE_RBTREE,
+ .volatile_reg = rpr0521_is_volatile_reg,
+};
+
+static int rpr0521_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct rpr0521_data *data;
+ struct iio_dev *indio_dev;
+ struct regmap *regmap;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ regmap = devm_regmap_init_i2c(client, &rpr0521_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&client->dev, "Regmap init failed!\n");
+ return PTR_ERR(regmap);
+ }
+
+ data = iio_priv(indio_dev);
+ i2c_set_clientdata(client, indio_dev);
+ data->client = client;
+ data->regmap = regmap;
+
+ mutex_init(&data->lock);
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &rpr0521_info;
+ indio_dev->name = RPR0521_DRV_NAME;
+ indio_dev->channels = rpr0521_channels;
+ indio_dev->num_channels = ARRAY_SIZE(rpr0521_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = rpr0521_init(data);
+ if (ret < 0) {
+ dev_err(&client->dev, "rpr0521 chip init failed\n");
+ return ret;
+ }
+ ret = iio_device_register(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ ret = pm_runtime_set_active(&client->dev);
+ if (ret < 0)
+ goto err_iio_unregister;
+
+ pm_runtime_enable(&client->dev);
+ pm_runtime_set_autosuspend_delay(&client->dev, RPR0521_SLEEP_DELAY_MS);
+ pm_runtime_use_autosuspend(&client->dev);
+
+ return 0;
+err_iio_unregister:
+ iio_device_unregister(indio_dev);
+ return ret;
+}
+
+static int rpr0521_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+ pm_runtime_disable(&client->dev);
+ pm_runtime_set_suspended(&client->dev);
+ pm_runtime_put_noidle(&client->dev);
+
+ iio_device_unregister(indio_dev);
+ rpr0521_poweroff(iio_priv(indio_dev));
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int rpr0521_runtime_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+
+ /* disable channels and sets {als,pxs}_dev_en to false */
+ mutex_lock(&data->lock);
+ ret = rpr0521_poweroff(data);
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int rpr0521_runtime_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct rpr0521_data *data = iio_priv(indio_dev);
+ int ret;
+
+ if (data->als_ps_need_en) {
+ ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
+ if (ret < 0)
+ return ret;
+ data->als_ps_need_en = false;
+ }
+
+ if (data->pxs_ps_need_en) {
+ ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
+ if (ret < 0)
+ return ret;
+ data->pxs_ps_need_en = false;
+ }
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops rpr0521_pm_ops = {
+ SET_RUNTIME_PM_OPS(rpr0521_runtime_suspend,
+ rpr0521_runtime_resume, NULL)
+};
+
+static const struct acpi_device_id rpr0521_acpi_match[] = {
+ {"RPR0521", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, rpr0521_acpi_match);
+
+static const struct i2c_device_id rpr0521_id[] = {
+ {"rpr0521", 0},
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, rpr0521_id);
+
+static struct i2c_driver rpr0521_driver = {
+ .driver = {
+ .name = RPR0521_DRV_NAME,
+ .pm = &rpr0521_pm_ops,
+ .acpi_match_table = ACPI_PTR(rpr0521_acpi_match),
+ },
+ .probe = rpr0521_probe,
+ .remove = rpr0521_remove,
+ .id_table = rpr0521_id,
+};
+
+module_i2c_driver(rpr0521_driver);
+
+MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
+MODULE_DESCRIPTION("RPR0521 ROHM Ambient Light and Proximity Sensor driver");
+MODULE_LICENSE("GPL v2");
--
1.9.1