diff options
| -rw-r--r-- | drivers/iio/light/veml6070.c | 131 |
1 files changed, 123 insertions, 8 deletions
diff --git a/drivers/iio/light/veml6070.c b/drivers/iio/light/veml6070.c index d11ae00f61f8..6d4483c85f30 100644 --- a/drivers/iio/light/veml6070.c +++ b/drivers/iio/light/veml6070.c @@ -6,7 +6,7 @@ * * IIO driver for VEML6070 (7-bit I2C slave addresses 0x38 and 0x39) * - * TODO: integration time, ACK signal + * TODO: ACK signal */ #include <linux/bitfield.h> @@ -15,6 +15,7 @@ #include <linux/mutex.h> #include <linux/err.h> #include <linux/delay.h> +#include <linux/units.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> @@ -29,18 +30,79 @@ #define VEML6070_COMMAND_RSRVD BIT(1) /* reserved, set to 1 */ #define VEML6070_COMMAND_SD BIT(0) /* shutdown mode when set */ -#define VEML6070_IT_10 0x01 /* integration time 1x */ +#define VEML6070_IT_05 0x00 +#define VEML6070_IT_10 0x01 +#define VEML6070_IT_20 0x02 +#define VEML6070_IT_40 0x03 + +#define VEML6070_MIN_RSET_KOHM 75 +#define VEML6070_MIN_IT_US 15625 /* Rset = 75 kohm, IT = 1/2 */ struct veml6070_data { struct i2c_client *client1; struct i2c_client *client2; u8 config; struct mutex lock; + u32 rset; + int it[4][2]; }; +static int veml6070_calc_it(struct device *dev, struct veml6070_data *data) +{ + int i, tmp_it; + + data->rset = 270000; + device_property_read_u32(dev, "vishay,rset-ohms", &data->rset); + + if (data->rset < 75000 || data->rset > 1200000) + return dev_err_probe(dev, -EINVAL, "Rset out of range\n"); + + /* + * convert to kohm to avoid overflows and work with the same units as + * in the datasheet and simplify UVI operations. + */ + data->rset /= KILO; + + tmp_it = VEML6070_MIN_IT_US * data->rset / VEML6070_MIN_RSET_KOHM; + for (i = 0; i < ARRAY_SIZE(data->it); i++) { + data->it[i][0] = (tmp_it << i) / MICRO; + data->it[i][1] = (tmp_it << i) % MICRO; + } + + return 0; +} + +static int veml6070_get_it(struct veml6070_data *data, int *val, int *val2) +{ + int it_idx = FIELD_GET(VEML6070_COMMAND_IT, data->config); + + *val = data->it[it_idx][0]; + *val2 = data->it[it_idx][1]; + + return IIO_VAL_INT_PLUS_MICRO; +} + +static int veml6070_set_it(struct veml6070_data *data, int val, int val2) +{ + int it_idx; + + for (it_idx = 0; it_idx < ARRAY_SIZE(data->it); it_idx++) { + if (data->it[it_idx][0] == val && data->it[it_idx][1] == val2) + break; + } + + if (it_idx >= ARRAY_SIZE(data->it)) + return -EINVAL; + + data->config = (data->config & ~VEML6070_COMMAND_IT) | + FIELD_PREP(VEML6070_COMMAND_IT, it_idx); + + return i2c_smbus_write_byte(data->client1, data->config); +} + static int veml6070_read(struct veml6070_data *data) { - int ret; + int ret, it_ms, val, val2; u8 msb, lsb; guard(mutex)(&data->lock); @@ -51,7 +113,9 @@ static int veml6070_read(struct veml6070_data *data) if (ret < 0) return ret; - msleep(125 + 10); /* measurement takes up to 125 ms for IT 1x */ + veml6070_get_it(data, &val, &val2); + it_ms = val * MILLI + val2 / (MICRO / MILLI); + msleep(it_ms + 10); ret = i2c_smbus_read_byte(data->client2); /* read MSB, address 0x39 */ if (ret < 0) @@ -81,26 +145,37 @@ static const struct iio_chan_spec veml6070_channels[] = { .modified = 1, .channel2 = IIO_MOD_LIGHT_UV, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME), }, { .type = IIO_UVINDEX, .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME), } }; -static int veml6070_to_uv_index(unsigned int val) +static int veml6070_to_uv_index(struct veml6070_data *data, unsigned int val) { /* * conversion of raw UV intensity values to UV index depends on * integration time (IT) and value of the resistor connected to - * the RSET pin (default: 270 KOhm) + * the RSET pin. */ unsigned int uvi[11] = { 187, 373, 560, /* low */ 746, 933, 1120, /* moderate */ 1308, 1494, /* high */ 1681, 1868, 2054}; /* very high */ - int i; + int i, it_idx; + + it_idx = FIELD_GET(VEML6070_COMMAND_IT, data->config); + + if (!it_idx) + val = (val * 270 / data->rset) << 1; + else + val = (val * 270 / data->rset) >> (it_idx - 1); for (i = 0; i < ARRAY_SIZE(uvi); i++) if (val <= uvi[i]) @@ -123,10 +198,44 @@ static int veml6070_read_raw(struct iio_dev *indio_dev, if (ret < 0) return ret; if (mask == IIO_CHAN_INFO_PROCESSED) - *val = veml6070_to_uv_index(ret); + *val = veml6070_to_uv_index(data, ret); else *val = ret; return IIO_VAL_INT; + case IIO_CHAN_INFO_INT_TIME: + return veml6070_get_it(data, val, val2); + default: + return -EINVAL; + } +} + +static int veml6070_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + struct veml6070_data *data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + *vals = (int *)data->it; + *length = 2 * ARRAY_SIZE(data->it); + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +static int veml6070_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct veml6070_data *data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + return veml6070_set_it(data, val, val2); default: return -EINVAL; } @@ -134,6 +243,8 @@ static int veml6070_read_raw(struct iio_dev *indio_dev, static const struct iio_info veml6070_info = { .read_raw = veml6070_read_raw, + .read_avail = veml6070_read_avail, + .write_raw = veml6070_write_raw, }; static void veml6070_i2c_unreg(void *p) @@ -164,6 +275,10 @@ static int veml6070_probe(struct i2c_client *client) indio_dev->name = VEML6070_DRV_NAME; indio_dev->modes = INDIO_DIRECT_MODE; + ret = veml6070_calc_it(&client->dev, data); + if (ret < 0) + return ret; + ret = devm_regulator_get_enable(&client->dev, "vdd"); if (ret < 0) return ret; |