diff options
Diffstat (limited to 'drivers/iio/light/ltr390.c')
-rw-r--r-- | drivers/iio/light/ltr390.c | 241 |
1 files changed, 220 insertions, 21 deletions
diff --git a/drivers/iio/light/ltr390.c b/drivers/iio/light/ltr390.c index fff1e899097d..7e58b50f3660 100644 --- a/drivers/iio/light/ltr390.c +++ b/drivers/iio/light/ltr390.c @@ -23,20 +23,30 @@ #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 +#define LTR390_FRACTIONAL_PRECISION 100 /* * At 20-bit resolution (integration time: 400ms) and 18x gain, 2300 counts of @@ -55,11 +65,19 @@ */ #define LTR390_WINDOW_FACTOR 1 +enum ltr390_mode { + LTR390_SET_ALS_MODE, + LTR390_SET_UVS_MODE, +}; + struct ltr390_data { struct regmap *regmap; struct i2c_client *client; /* Protects device from simulataneous reads */ struct mutex lock; + enum ltr390_mode mode; + int gain; + int int_time_us; }; static const struct regmap_config ltr390_regmap_config = { @@ -75,8 +93,6 @@ 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) { @@ -87,6 +103,38 @@ static int ltr390_register_read(struct ltr390_data *data, u8 register_address) return get_unaligned_le24(recieve_buffer); } +static int ltr390_set_mode(struct ltr390_data *data, enum ltr390_mode mode) +{ + int ret; + + if (data->mode == mode) + return 0; + + switch (mode) { + case LTR390_SET_ALS_MODE: + ret = regmap_clear_bits(data->regmap, LTR390_MAIN_CTRL, LTR390_UVS_MODE); + break; + + case LTR390_SET_UVS_MODE: + ret = regmap_set_bits(data->regmap, LTR390_MAIN_CTRL, LTR390_UVS_MODE); + break; + } + + if (ret) + return ret; + + data->mode = mode; + return 0; +} + +static int ltr390_counts_per_uvi(struct ltr390_data *data) +{ + const int orig_gain = 18; + const int orig_int_time = 400; + + return DIV_ROUND_CLOSEST(23 * data->gain * data->int_time_us, 10 * orig_gain * orig_int_time); +} + static int ltr390_read_raw(struct iio_dev *iio_device, struct iio_chan_spec const *chan, int *val, int *val2, long mask) @@ -94,29 +142,174 @@ 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); - if (ret < 0) - return ret; + switch (chan->type) { + case IIO_UVINDEX: + ret = ltr390_set_mode(data, LTR390_SET_UVS_MODE); + if (ret < 0) + return ret; + + ret = ltr390_register_read(data, LTR390_UVS_DATA); + if (ret < 0) + return ret; + break; + + case IIO_LIGHT: + ret = ltr390_set_mode(data, LTR390_SET_ALS_MODE); + if (ret < 0) + return ret; + + ret = ltr390_register_read(data, LTR390_ALS_DATA); + if (ret < 0) + return ret; + break; + + default: + return -EINVAL; + } *val = ret; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: - *val = LTR390_WINDOW_FACTOR; - *val2 = LTR390_COUNTS_PER_UVI; - return IIO_VAL_FRACTIONAL; + switch (chan->type) { + case IIO_UVINDEX: + *val = LTR390_WINDOW_FACTOR * LTR390_FRACTIONAL_PRECISION; + *val2 = ltr390_counts_per_uvi(data); + return IIO_VAL_FRACTIONAL; + + case IIO_LIGHT: + *val = LTR390_WINDOW_FACTOR * 6 * 100; + *val2 = data->gain * data->int_time_us; + return IIO_VAL_FRACTIONAL; + + default: + return -EINVAL; + } + + 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_channels[] = { + /* UV sensor */ + { + .type = IIO_UVINDEX, + .scan_index = 0, + .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) + }, + /* ALS sensor */ + { + .type = IIO_LIGHT, + .scan_index = 1, + .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 const struct iio_chan_spec ltr390_channel = { - .type = IIO_UVINDEX, - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 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) @@ -139,11 +332,18 @@ 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; + /* default mode for ltr390 is ALS mode */ + data->mode = LTR390_SET_ALS_MODE; + mutex_init(&data->lock); indio_dev->info = <r390_info; - indio_dev->channels = <r390_channel; - indio_dev->num_channels = 1; + indio_dev->channels = ltr390_channels; + indio_dev->num_channels = ARRAY_SIZE(ltr390_channels); indio_dev->name = "ltr390"; ret = regmap_read(data->regmap, LTR390_PART_ID, &part_number); @@ -161,8 +361,7 @@ static int ltr390_probe(struct i2c_client *client) /* Wait for the registers to reset before proceeding */ usleep_range(1000, 2000); - ret = regmap_set_bits(data->regmap, LTR390_MAIN_CTRL, - LTR390_SENSOR_ENABLE | LTR390_UVS_MODE); + ret = regmap_set_bits(data->regmap, LTR390_MAIN_CTRL, LTR390_SENSOR_ENABLE); if (ret) return dev_err_probe(dev, ret, "failed to enable the sensor\n"); |