Add support for configuring and reading the gain and resolution (integration time). Also provide the available values for gain and resoltion respectively via `read_avail` callback. Signed-off-by: Abhash Jha <abhashkumarjha123@xxxxxxxxx> --- drivers/iio/light/ltr390.c | 136 ++++++++++++++++++++++++++++++++++--- 1 file changed, 125 insertions(+), 11 deletions(-) diff --git a/drivers/iio/light/ltr390.c b/drivers/iio/light/ltr390.c index fff1e8990..ee3d30075 100644 --- a/drivers/iio/light/ltr390.c +++ b/drivers/iio/light/ltr390.c @@ -23,21 +23,29 @@ #include <linux/module.h> #include <linux/mutex.h> #include <linux/regmap.h> +#include <linux/bitfield.h> #include <linux/iio/iio.h> #include <asm/unaligned.h> -#define LTR390_MAIN_CTRL 0x00 -#define LTR390_PART_ID 0x06 -#define LTR390_UVS_DATA 0x10 +#define LTR390_MAIN_CTRL 0x00 +#define LTR390_ALS_UVS_MEAS_RATE 0x04 +#define LTR390_ALS_UVS_GAIN 0x05 +#define LTR390_PART_ID 0x06 +#define LTR390_ALS_DATA 0x0D +#define LTR390_UVS_DATA 0x10 +#define LTR390_INT_CFG 0x19 + +#define LTR390_PART_NUMBER_ID 0xb +#define LTR390_ALS_UVS_GAIN_MASK 0x07 +#define LTR390_ALS_UVS_INT_TIME_MASK 0x70 +#define LTR390_ALS_UVS_INT_TIME(x) FIELD_PREP(LTR390_ALS_UVS_INT_TIME_MASK, (x)) #define LTR390_SW_RESET BIT(4) #define LTR390_UVS_MODE BIT(3) #define LTR390_SENSOR_ENABLE BIT(1) -#define LTR390_PART_NUMBER_ID 0xb - /* * At 20-bit resolution (integration time: 400ms) and 18x gain, 2300 counts of * the sensor are equal to 1 UV Index [Datasheet Page#8]. @@ -60,6 +68,8 @@ struct ltr390_data { struct i2c_client *client; /* Protects device from simulataneous reads */ struct mutex lock; + int gain; + int int_time_us; }; static const struct regmap_config ltr390_regmap_config = { @@ -75,8 +85,6 @@ static int ltr390_register_read(struct ltr390_data *data, u8 register_address) int ret; u8 recieve_buffer[3]; - guard(mutex)(&data->lock); - ret = regmap_bulk_read(data->regmap, register_address, recieve_buffer, sizeof(recieve_buffer)); if (ret) { @@ -94,6 +102,7 @@ static int ltr390_read_raw(struct iio_dev *iio_device, int ret; struct ltr390_data *data = iio_priv(iio_device); + guard(mutex)(&data->lock); switch (mask) { case IIO_CHAN_INFO_RAW: ret = ltr390_register_read(data, LTR390_UVS_DATA); @@ -105,18 +114,118 @@ static int ltr390_read_raw(struct iio_dev *iio_device, *val = LTR390_WINDOW_FACTOR; *val2 = LTR390_COUNTS_PER_UVI; return IIO_VAL_FRACTIONAL; + + case IIO_CHAN_INFO_INT_TIME: + *val = data->int_time_us; + return IIO_VAL_INT; + default: return -EINVAL; } } -static const struct iio_info ltr390_info = { - .read_raw = ltr390_read_raw, -}; +/* integration time in us */ +static const int ltr390_int_time_map_us[] = { 400000, 200000, 100000, 50000, 25000, 12500 }; +static const int ltr390_gain_map[] = { 1, 3, 6, 9, 18 }; static const struct iio_chan_spec ltr390_channel = { .type = IIO_UVINDEX, - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) | BIT(IIO_CHAN_INFO_SCALE) +}; + +static int ltr390_set_gain(struct ltr390_data *data, int val) +{ + int ret, idx; + + for (idx = 0; idx < ARRAY_SIZE(ltr390_gain_map); idx++) { + if (ltr390_gain_map[idx] != val) + continue; + + guard(mutex)(&data->lock); + ret = regmap_update_bits(data->regmap, + LTR390_ALS_UVS_GAIN, + LTR390_ALS_UVS_GAIN_MASK, idx); + if (ret) + return ret; + + data->gain = ltr390_gain_map[idx]; + return 0; + } + + return -EINVAL; +} + +static int ltr390_set_int_time(struct ltr390_data *data, int val) +{ + int ret, idx; + + for (idx = 0; idx < ARRAY_SIZE(ltr390_int_time_map_us); idx++) { + if (ltr390_int_time_map_us[idx] != val) + continue; + + guard(mutex)(&data->lock); + ret = regmap_update_bits(data->regmap, + LTR390_ALS_UVS_MEAS_RATE, + LTR390_ALS_UVS_INT_TIME_MASK, + LTR390_ALS_UVS_INT_TIME(idx)); + if (ret) + return ret; + + data->int_time_us = ltr390_int_time_map_us[idx]; + return 0; + } + + return -EINVAL; +} + +static int ltr390_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_SCALE: + *length = ARRAY_SIZE(ltr390_gain_map); + *type = IIO_VAL_INT; + *vals = ltr390_gain_map; + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_INT_TIME: + *length = ARRAY_SIZE(ltr390_int_time_map_us); + *type = IIO_VAL_INT; + *vals = ltr390_int_time_map_us; + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +static int ltr390_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct ltr390_data *data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + if (val2 != 0) + return -EINVAL; + + return ltr390_set_gain(data, val); + + case IIO_CHAN_INFO_INT_TIME: + if (val2 != 0) + return -EINVAL; + + return ltr390_set_int_time(data, val); + + default: + return -EINVAL; + } +} + +static const struct iio_info ltr390_info = { + .read_raw = ltr390_read_raw, + .write_raw = ltr390_write_raw, + .read_avail = ltr390_read_avail, }; static int ltr390_probe(struct i2c_client *client) @@ -139,6 +248,11 @@ static int ltr390_probe(struct i2c_client *client) "regmap initialization failed\n"); data->client = client; + /* default value of integration time from pg: 15 of the datasheet */ + data->int_time_us = 100000; + /* default value of gain from pg: 16 of the datasheet */ + data->gain = 3; + mutex_init(&data->lock); indio_dev->info = <r390_info; -- 2.43.0