On 27/04/15 16:34, Tiberiu Breana wrote:
> Minimal implementation of an IIO driver for the Sensortek
> STK3310 ambient light and proximity sensor. The STK3311
> model is also supported.
>
> Includes:
> - ACPI support;
> - read_raw and write_raw;
> - reading and setting configuration parameters for gain/scale
> and integration time for both ALS and PS.
> - power management
>
> Signed-off-by: Tiberiu Breana <tiberiu.a.breana@xxxxxxxxx>
A couple of trivial comments inline. None are major enough
to warant another spin of the patch though, so applied to the
togreg branch of iio.git This will get pushed out as testing
sometime soonish (travelling).
Thanks,
Jonathan
> ---
> drivers/iio/light/Kconfig | 11 ++
> drivers/iio/light/Makefile | 1 +
> drivers/iio/light/stk3310.c | 471 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 483 insertions(+)
> create mode 100644 drivers/iio/light/stk3310.c
>
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index a437bad..3d7bafa 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -175,6 +175,17 @@ config LTR501
> This driver can also be built as a module. If so, the module
> will be called ltr501.
>
> +config STK3310
> + tristate "STK3310 ALS and proximity sensor"
> + depends on I2C
> + help
> + Say yes here to get support for the Sensortek STK3310 ambient light
> + and proximity sensor. The STK3311 model is also supported by this
> + driver.
> +
> + Choosing M will build the driver as a module. If so, the module
> + will be called stk3310.
> +
> config TCS3414
> tristate "TAOS TCS3414 digital color sensor"
> depends on I2C
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index ad7c30f..90e7fd2 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -18,6 +18,7 @@ obj-$(CONFIG_JSA1212) += jsa1212.o
> obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o
> obj-$(CONFIG_LTR501) += ltr501.o
> obj-$(CONFIG_SENSORS_TSL2563) += tsl2563.o
> +obj-$(CONFIG_STK3310) += stk3310.o
> obj-$(CONFIG_TCS3414) += tcs3414.o
> obj-$(CONFIG_TCS3472) += tcs3472.o
> obj-$(CONFIG_TSL4531) += tsl4531.o
> diff --git a/drivers/iio/light/stk3310.c b/drivers/iio/light/stk3310.c
> new file mode 100644
> index 0000000..0f8c450
> --- /dev/null
> +++ b/drivers/iio/light/stk3310.c
> @@ -0,0 +1,471 @@
> +/**
> + * Sensortek STK3310/STK3311 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 STK3310/STK3311. 7-bit I2C address: 0x48.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/i2c.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define STK3310_REG_STATE 0x00
> +#define STK3310_REG_PSCTRL 0x01
> +#define STK3310_REG_ALSCTRL 0x02
> +#define STK3310_REG_PS_DATA_MSB 0x11
> +#define STK3310_REG_PS_DATA_LSB 0x12
> +#define STK3310_REG_ALS_DATA_MSB 0x13
> +#define STK3310_REG_ALS_DATA_LSB 0x14
> +#define STK3310_REG_ID 0x3E
> +#define STK3310_MAX_REG 0x80
> +
> +#define STK3310_STATE_EN_PS 0x01
> +#define STK3310_STATE_EN_ALS 0x02
> +#define STK3310_STATE_STANDBY 0x00
> +
> +#define STK3310_CHIP_ID_VAL 0x13
> +#define STK3311_CHIP_ID_VAL 0x1D
> +#define STK3310_PS_MAX_VAL 0xFFFF
> +
> +#define STK3310_DRIVER_NAME "stk3310"
> +#define STK3310_REGMAP_NAME "stk3310_regmap"
> +
> +#define STK3310_SCALE_AVAILABLE "6.4 1.6 0.4 0.1"
> +
> +#define STK3310_IT_AVAILABLE \
> + "0.000185 0.000370 0.000741 0.001480 0.002960 0.005920 0.011840 " \
> + "0.023680 0.047360 0.094720 0.189440 0.378880 0.757760 1.515520 " \
> + "3.031040 6.062080"
> +
> +#define STK3310_REGFIELD(name) \
> + do { \
> + data->reg_##name = \
> + devm_regmap_field_alloc(&client->dev, regmap, \
> + stk3310_reg_field_##name); \
> + if (IS_ERR(data->reg_##name)) { \
> + dev_err(&client->dev, "reg field alloc failed.\n"); \
> + return PTR_ERR(data->reg_##name); \
> + } \
> + } while (0)
> +
> +static const struct reg_field stk3310_reg_field_state =
> + REG_FIELD(STK3310_REG_STATE, 0, 2);
> +static const struct reg_field stk3310_reg_field_als_gain =
> + REG_FIELD(STK3310_REG_ALSCTRL, 4, 5);
> +static const struct reg_field stk3310_reg_field_ps_gain =
> + REG_FIELD(STK3310_REG_PSCTRL, 4, 5);
> +static const struct reg_field stk3310_reg_field_als_it =
> + REG_FIELD(STK3310_REG_ALSCTRL, 0, 3);
> +static const struct reg_field stk3310_reg_field_ps_it =
> + REG_FIELD(STK3310_REG_PSCTRL, 0, 3);
> +
> +/*
> + * Maximum PS values with regard to scale. Used to export the 'inverse'
> + * PS value (high values for far objects, low values for near objects).
> + */
> +static const int stk3310_ps_max[4] = {
> + STK3310_PS_MAX_VAL / 64,
> + STK3310_PS_MAX_VAL / 16,
> + STK3310_PS_MAX_VAL / 4,
> + STK3310_PS_MAX_VAL,
> +};
> +
> +static const int stk3310_scale_table[][2] = {
> + {6, 400000}, {1, 600000}, {0, 400000}, {0, 100000}
> +};
> +
> +/* Integration time in seconds, microseconds */
> +static const int stk3310_it_table[][2] = {
> + {0, 185}, {0, 370}, {0, 741}, {0, 1480},
> + {0, 2960}, {0, 5920}, {0, 11840}, {0, 23680},
> + {0, 47360}, {0, 94720}, {0, 189440}, {0, 378880},
> + {0, 757760}, {1, 515520}, {3, 31040}, {6, 62080},
> +};
> +
> +struct stk3310_data {
> + struct i2c_client *client;
> + struct mutex lock;
> + bool als_enabled;
> + bool ps_enabled;
> + struct regmap *regmap;
> + struct regmap_field *reg_state;
> + struct regmap_field *reg_als_gain;
> + struct regmap_field *reg_ps_gain;
> + struct regmap_field *reg_als_it;
> + struct regmap_field *reg_ps_it;
> +};
> +
> +static const struct iio_chan_spec stk3310_channels[] = {
> + {
> + .type = IIO_LIGHT,
> + .info_mask_separate =
> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> + BIT(IIO_CHAN_INFO_INT_TIME),
> + },
> + {
> + .type = IIO_PROXIMITY,
> + .info_mask_separate =
> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> + BIT(IIO_CHAN_INFO_INT_TIME),
> + }
> +};
> +
> +static IIO_CONST_ATTR(in_illuminance_scale_available, STK3310_SCALE_AVAILABLE);
> +
> +static IIO_CONST_ATTR(in_proximity_scale_available, STK3310_SCALE_AVAILABLE);
> +
> +static IIO_CONST_ATTR(in_illuminance_integration_time_available,
> + STK3310_IT_AVAILABLE);
> +
> +static IIO_CONST_ATTR(in_proximity_integration_time_available,
> + STK3310_IT_AVAILABLE);
> +
> +static struct attribute *stk3310_attributes[] = {
> + &iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
> + &iio_const_attr_in_proximity_scale_available.dev_attr.attr,
> + &iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
> + &iio_const_attr_in_proximity_integration_time_available.dev_attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group stk3310_attribute_group = {
> + .attrs = stk3310_attributes
> +};
> +
> +static int stk3310_get_index(const int table[][2], int table_size,
> + int val, int val2)
> +{
> + int i;
> +
> + for (i = 0; i < table_size; i++) {
> + if (val == table[i][0] && val2 == table[i][1])
> + return i;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int stk3310_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + u8 reg;
> + u16 buf;
> + int ret;
> + unsigned int index;
> + struct stk3310_data *data = iio_priv(indio_dev);
> + struct i2c_client *client = data->client;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + if (chan->type == IIO_LIGHT)
> + reg = STK3310_REG_ALS_DATA_MSB;
> + else if (chan->type == IIO_PROXIMITY)
> + reg = STK3310_REG_PS_DATA_MSB;
> + else
> + return -EINVAL;
> + mutex_lock(&data->lock);
> + ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
> + if (ret < 0) {
> + dev_err(&client->dev, "register read failed\n");
> + mutex_unlock(&data->lock);
> + return ret;
> + }
> + *val = swab16(buf);
> + if (chan->type == IIO_PROXIMITY) {
> + /*
> + * Invert the proximity data so we return low values
> + * for close objects and high values for far ones.
> + */
> + regmap_field_read(data->reg_ps_gain, &index);
> + *val = stk3310_ps_max[index] - *val;
> + }
> + mutex_unlock(&data->lock);
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_INT_TIME:
> + if (chan->type == IIO_LIGHT)
> + regmap_field_read(data->reg_als_it, &index);
> + else
> + regmap_field_read(data->reg_ps_it, &index);
> + *val = stk3310_it_table[index][0];
> + *val2 = stk3310_it_table[index][1];
> + return IIO_VAL_INT_PLUS_MICRO;
> + case IIO_CHAN_INFO_SCALE:
> + if (chan->type == IIO_LIGHT)
> + regmap_field_read(data->reg_als_gain, &index);
> + else
> + regmap_field_read(data->reg_ps_gain, &index);
> + *val = stk3310_scale_table[index][0];
> + *val2 = stk3310_scale_table[index][1];
> + return IIO_VAL_INT_PLUS_MICRO;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int stk3310_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long mask)
> +{
> + int ret;
> + unsigned int index;
> + struct stk3310_data *data = iio_priv(indio_dev);
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_INT_TIME:
> + index = stk3310_get_index(stk3310_it_table,
> + ARRAY_SIZE(stk3310_it_table),
> + val, val2);
> + if (index < 0)
> + return -EINVAL;
> + mutex_lock(&data->lock);
> + if (chan->type == IIO_LIGHT)
> + ret = regmap_field_write(data->reg_als_it, index);
> + else
> + ret = regmap_field_write(data->reg_ps_it, index);
> + if (ret < 0)
> + dev_err(&data->client->dev,
> + "sensor configuration failed\n");
> + mutex_unlock(&data->lock);
> + return ret;
> +
> + case IIO_CHAN_INFO_SCALE:
> + index = stk3310_get_index(stk3310_scale_table,
> + ARRAY_SIZE(stk3310_scale_table),
> + val, val2);
> + if (index < 0)
> + return -EINVAL;
> + mutex_lock(&data->lock);
> + if (chan->type == IIO_LIGHT)
> + ret = regmap_field_write(data->reg_als_gain, index);
> + else
> + ret = regmap_field_write(data->reg_ps_gain, index);
> + if (ret < 0)
> + dev_err(&data->client->dev,
> + "sensor configuration failed\n");
> + mutex_unlock(&data->lock);
> + return ret;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static const struct iio_info stk3310_info = {
> + .driver_module = THIS_MODULE,
> + .read_raw = stk3310_read_raw,
> + .write_raw = stk3310_write_raw,
> + .attrs = &stk3310_attribute_group,
> +};
> +
> +static int stk3310_set_state(struct stk3310_data *data, u8 state)
> +{
> + int ret;
> + struct i2c_client *client = data->client;
> +
> + /* 3-bit state; 0b100 is not supported. */
> + if (state > 7 || state == 4)
> + return -EINVAL;
> +
> + mutex_lock(&data->lock);
> + ret = regmap_field_write(data->reg_state, state);
> + if (ret < 0) {
> + dev_err(&client->dev, "failed to change sensor state\n");
> + } else if (state != STK3310_STATE_STANDBY) {
> + /* Don't reset the 'enabled' flags if we're going in standby */
For clarity I'd have been tempted to waste a bit of space and have
ps_enabled_prestandy or something like that so as to have kept a single
meaning for these variables, whatever the state.
> + data->ps_enabled = !!(state & 0x01);
> + data->als_enabled = !!(state & 0x02);
> + }
> + mutex_unlock(&data->lock);
> +
> + return ret;
> +}
> +
> +static int stk3310_init(struct iio_dev *indio_dev)
> +{
> + int ret;
> + int chipid;
> + u8 state;
> + struct stk3310_data *data = iio_priv(indio_dev);
> + struct i2c_client *client = data->client;
> +
> + regmap_read(data->regmap, STK3310_REG_ID, &chipid);
> + if (chipid != STK3310_CHIP_ID_VAL &&
> + chipid != STK3311_CHIP_ID_VAL) {
> + dev_err(&client->dev, "invalid chip id: 0x%x\n", chipid);
> + return -ENODEV;
> + }
> +
> + state = STK3310_STATE_EN_ALS | STK3310_STATE_EN_PS;
> + ret = stk3310_set_state(data, state);
> + if (ret < 0)
> + dev_err(&client->dev, "failed to enable sensor");
> +
> + return ret;
> +}
> +
> +static bool stk3310_is_volatile_reg(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case STK3310_REG_ALS_DATA_MSB:
> + case STK3310_REG_ALS_DATA_LSB:
> + case STK3310_REG_PS_DATA_LSB:
> + case STK3310_REG_PS_DATA_MSB:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> +static struct regmap_config stk3310_regmap_config = {
> + .name = STK3310_REGMAP_NAME,
> + .reg_bits = 8,
> + .val_bits = 8,
> + .max_register = STK3310_MAX_REG,
> + .cache_type = REGCACHE_RBTREE,
> + .volatile_reg = stk3310_is_volatile_reg,
> +};
> +
> +static int stk3310_regmap_init(struct stk3310_data *data)
> +{
> + struct regmap *regmap;
> + struct i2c_client *client;
> +
> + client = data->client;
> + regmap = devm_regmap_init_i2c(client, &stk3310_regmap_config);
> + if (IS_ERR(regmap)) {
> + dev_err(&client->dev, "regmap initialization failed.\n");
> + return PTR_ERR(regmap);
> + }
> + data->regmap = regmap;
> +
> + STK3310_REGFIELD(state);
This is nice and neat and tidy - rather feels like regmap would benefit
from an array of fields allocator but this is a good alternative.
> + STK3310_REGFIELD(als_gain);
> + STK3310_REGFIELD(ps_gain);
> + STK3310_REGFIELD(als_it);
> + STK3310_REGFIELD(ps_it);
> +
> + return 0;
> +}
> +
> +static int stk3310_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + int ret;
> + struct iio_dev *indio_dev;
> + struct stk3310_data *data;
> +
> + 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);
> + mutex_init(&data->lock);
> +
> + ret = stk3310_regmap_init(data);
> + if (ret < 0)
> + return ret;
> +
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->info = &stk3310_info;
> + indio_dev->name = STK3310_DRIVER_NAME;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->channels = stk3310_channels;
> + indio_dev->num_channels = ARRAY_SIZE(stk3310_channels);
> +
> + ret = stk3310_init(indio_dev);
> + if (ret < 0)
> + return ret;
> +
> + ret = iio_device_register(indio_dev);
> + if (ret < 0) {
> + dev_err(&client->dev, "device_register failed\n");
> + stk3310_set_state(data, STK3310_STATE_STANDBY);
> + }
> +
> + return ret;
> +}
> +
> +static int stk3310_remove(struct i2c_client *client)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + iio_device_unregister(indio_dev);
> + return stk3310_set_state(iio_priv(indio_dev), STK3310_STATE_STANDBY);
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int stk3310_suspend(struct device *dev)
> +{
> + struct stk3310_data *data;
> +
> + data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
> +
> + return stk3310_set_state(data, STK3310_STATE_STANDBY);
> +}
> +
> +static int stk3310_resume(struct device *dev)
> +{
> + int state = 0;
> + struct stk3310_data *data;
> +
> + data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
> + if (data->ps_enabled)
> + state |= STK3310_STATE_EN_PS;
> + if (data->als_enabled)
> + state |= STK3310_STATE_EN_ALS;
> +
> + return stk3310_set_state(data, state);
> +}
> +
> +static SIMPLE_DEV_PM_OPS(stk3310_pm_ops, stk3310_suspend, stk3310_resume);
> +
> +#define STK3310_PM_OPS (&stk3310_pm_ops)
> +#else
> +#define STK3310_PM_OPS NULL
> +#endif
> +
> +static const struct i2c_device_id stk3310_i2c_id[] = {
> + {"STK3310", 0},
> + {"STK3311", 0},
> + {}
> +};
> +
> +static const struct acpi_device_id stk3310_acpi_id[] = {
> + {"STK3310", 0},
> + {"STK3311", 0},
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(acpi, stk3310_acpi_id);
> +
> +static struct i2c_driver stk3310_driver = {
> + .driver = {
> + .name = "stk3310",
> + .pm = STK3310_PM_OPS,
> + .acpi_match_table = ACPI_PTR(stk3310_acpi_id),
> + },
> + .probe = stk3310_probe,
> + .remove = stk3310_remove,
> + .id_table = stk3310_i2c_id,
> +};
> +
> +module_i2c_driver(stk3310_driver);
> +
> +MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@xxxxxxxxx>");
> +MODULE_DESCRIPTION("STK3310 Ambient Light and Proximity Sensor driver");
> +MODULE_LICENSE("GPL v2");
>
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