The current scale is not ABI-compliant as it is just the sensor gain
instead of the value that acts as a multiplier to be applied to the raw
value (there is no offset).
Use the iio-gts helpers to obtain the proper scale values according to
the gain and integration time to match the resolution tables from the
datasheet.
Fixes: c5a23f80c164 ("iio: light: add support for veml3235")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
---
drivers/iio/light/Kconfig | 1 +
drivers/iio/light/veml3235.c | 252 ++++++++++++++++++++++++-------------------
2 files changed, 140 insertions(+), 113 deletions(-)
diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 0cf9cf2a3f94..12864691a7ff 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -656,6 +656,7 @@ config VCNL4035
config VEML3235
tristate "VEML3235 ambient light sensor"
select REGMAP_I2C
+ select IIO_GTS_HELPER
depends on I2C
help
Say Y here if you want to build a driver for the Vishay VEML3235
diff --git a/drivers/iio/light/veml3235.c b/drivers/iio/light/veml3235.c
index 66361c3012a3..4ace3f8e95f1 100644
--- a/drivers/iio/light/veml3235.c
+++ b/drivers/iio/light/veml3235.c
@@ -11,6 +11,7 @@
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/iio/iio.h>
+#include <linux/iio/iio-gts-helper.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
@@ -35,17 +36,33 @@ struct veml3235_data {
struct device *dev;
struct regmap *regmap;
struct veml3235_rf rf;
+ struct iio_gts gts;
};
-static const int veml3235_it_times[][2] = {
- { 0, 50000 },
- { 0, 100000 },
- { 0, 200000 },
- { 0, 400000 },
- { 0, 800000 },
+static const struct iio_itime_sel_mul veml3235_it_sel[] = {
+ GAIN_SCALE_ITIME_US(50000, 0, 1),
+ GAIN_SCALE_ITIME_US(100000, 1, 2),
+ GAIN_SCALE_ITIME_US(200000, 2, 4),
+ GAIN_SCALE_ITIME_US(400000, 3, 8),
+ GAIN_SCALE_ITIME_US(800000, 4, 16),
};
-static const int veml3235_scale_vals[] = { 1, 2, 4, 8 };
+/*
+ * The MSB (DG) doubles the value of the rest of the field, which leads to
+ * two possible combinations to obtain gain = 2 and gain = 4. The gain
+ * handlding can be simplified by restricting DG = 1 to the only gain that
+ * really requires it, gain = 8. Note that "X10" is a reserved value.
+ */
+#define VEML3235_SEL_GAIN_X1 0
+#define VEML3235_SEL_GAIN_X2 1
+#define VEML3235_SEL_GAIN_X4 3
+#define VEML3235_SEL_GAIN_X8 7
+static const struct iio_gain_sel_pair veml3235_gain_sel[] = {
+ GAIN_SCALE_GAIN(1, VEML3235_SEL_GAIN_X1),
+ GAIN_SCALE_GAIN(2, VEML3235_SEL_GAIN_X2),
+ GAIN_SCALE_GAIN(4, VEML3235_SEL_GAIN_X4),
+ GAIN_SCALE_GAIN(8, VEML3235_SEL_GAIN_X8),
+};
static int veml3235_power_on(struct veml3235_data *data)
{
@@ -111,112 +128,99 @@ static const struct regmap_config veml3235_regmap_config = {
static int veml3235_get_it(struct veml3235_data *data, int *val, int *val2)
{
- int ret, reg;
+ int ret, it_idx;
- ret = regmap_field_read(data->rf.it, ®);
+ ret = regmap_field_read(data->rf.it, &it_idx);
if (ret)
return ret;
- switch (reg) {
- case 0:
- *val2 = 50000;
- break;
- case 1:
- *val2 = 100000;
- break;
- case 2:
- *val2 = 200000;
- break;
- case 3:
- *val2 = 400000;
- break;
- case 4:
- *val2 = 800000;
- break;
- default:
- return -EINVAL;
- }
+ ret = iio_gts_find_int_time_by_sel(&data->gts, it_idx);
+ if (ret < 0)
+ return ret;
+ *val2 = ret;
*val = 0;
return IIO_VAL_INT_PLUS_MICRO;
}
-static int veml3235_set_it(struct iio_dev *indio_dev, int val, int val2)
+static int veml3235_set_it(struct iio_dev *indio_dev, int val2)
{
struct veml3235_data *data = iio_priv(indio_dev);
- int ret, new_it;
+ int ret, gain_idx, it_idx, new_gain, prev_gain, prev_it;
+ bool in_range;
- if (val)
+ if (!iio_gts_valid_time(&data->gts, val2))
return -EINVAL;
- switch (val2) {
- case 50000:
- new_it = 0x00;
- break;
- case 100000:
- new_it = 0x01;
- break;
- case 200000:
- new_it = 0x02;
- break;
- case 400000:
- new_it = 0x03;
- break;
- case 800000:
- new_it = 0x04;
- break;
- default:
- return -EINVAL;
- }
+ ret = regmap_field_read(data->rf.it, &it_idx);
+ if (ret)
+ return ret;
- ret = regmap_field_write(data->rf.it, new_it);
- if (ret) {
- dev_err(data->dev,
- "failed to update integration time: %d\n", ret);
+ ret = regmap_field_read(data->rf.gain, &gain_idx);
+ if (ret)
return ret;
- }
- return 0;
+ prev_it = iio_gts_find_int_time_by_sel(&data->gts, it_idx);
+ if (prev_it < 0)
+ return prev_it;
+
+ if (prev_it == val2)
+ return 0;
+
+ prev_gain = iio_gts_find_gain_by_sel(&data->gts, gain_idx);
+ if (prev_gain < 0)
+ return prev_gain;
+
+ ret = iio_gts_find_new_gain_by_gain_time_min(&data->gts, prev_gain, prev_it,
+ val2, &new_gain, &in_range);
+ if (ret)
+ return ret;
+
+ if (!in_range)
+ dev_dbg(data->dev, "Optimal gain out of range\n");
+
+ ret = iio_gts_find_sel_by_int_time(&data->gts, val2);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_field_write(data->rf.it, ret);
+ if (ret)
+ return ret;
+
+ ret = iio_gts_find_sel_by_gain(&data->gts, new_gain);
+ if (ret < 0)
+ return ret;
+
+ return regmap_field_write(data->rf.gain, ret);
}
-static int veml3235_set_gain(struct iio_dev *indio_dev, int val, int val2)
+static int veml3235_set_scale(struct iio_dev *indio_dev, int val, int val2)
{
struct veml3235_data *data = iio_priv(indio_dev);
- int ret, new_gain;
+ int ret, it_idx, gain_sel, time_sel;
- if (val2 != 0)
- return -EINVAL;
-
- switch (val) {
- case 1:
- new_gain = 0x00;
- break;
- case 2:
- new_gain = 0x01;
- break;
- case 4:
- new_gain = 0x03;
- break;
- case 8:
- new_gain = 0x07;
- break;
- default:
- return -EINVAL;
- }
+ ret = regmap_field_read(data->rf.it, &it_idx);
+ if (ret)
+ return ret;
- ret = regmap_field_write(data->rf.gain, new_gain);
- if (ret) {
- dev_err(data->dev, "failed to set gain: %d\n", ret);
+ ret = iio_gts_find_gain_sel_in_times(&data->gts, val, val2, &gain_sel,
+ &time_sel);
+ if (ret)
return ret;
+
+ if (it_idx != time_sel) {
+ ret = regmap_field_write(data->rf.it, time_sel);
+ if (ret)
+ return ret;
}
- return 0;
+ return regmap_field_write(data->rf.gain, gain_sel);
}
-static int veml3235_get_gain(struct veml3235_data *data, int *val)
+static int veml3235_get_scale(struct veml3235_data *data, int *val, int *val2)
{
- int ret, reg;
+ int gain, it, reg, ret;
ret = regmap_field_read(data->rf.gain, ®);
if (ret) {
@@ -224,25 +228,25 @@ static int veml3235_get_gain(struct veml3235_data *data, int *val)
return ret;
}
- switch (reg & 0x03) {
- case 0:
- *val = 1;
- break;
- case 1:
- *val = 2;
- break;
- case 3:
- *val = 4;
- break;
- default:
- return -EINVAL;
+ gain = iio_gts_find_gain_by_sel(&data->gts, reg);
+ if (gain < 0)
+ return gain;
+
+ ret = regmap_field_read(data->rf.it, ®);
+ if (ret) {
+ dev_err(data->dev, "failed to read integration time %d\n", ret);
+ return ret;
}
- /* Double gain */
- if (reg & 0x04)
- *val *= 2;
+ it = iio_gts_find_int_time_by_sel(&data->gts, reg);
+ if (it < 0)
+ return it;
- return IIO_VAL_INT;
+ ret = iio_gts_get_scale(&data->gts, gain, it, val, val2);
+ if (ret)
+ return ret;
+
+ return IIO_VAL_INT_PLUS_NANO;
}
static int veml3235_read_raw(struct iio_dev *indio_dev,
@@ -276,7 +280,7 @@ static int veml3235_read_raw(struct iio_dev *indio_dev,
case IIO_CHAN_INFO_INT_TIME:
return veml3235_get_it(data, val, val2);
case IIO_CHAN_INFO_SCALE:
- return veml3235_get_gain(data, val);
+ return veml3235_get_scale(data, val, val2);
default:
return -EINVAL;
}
@@ -287,17 +291,27 @@ static int veml3235_read_avail(struct iio_dev *indio_dev,
const int **vals, int *type, int *length,
long mask)
{
+ struct veml3235_data *data = iio_priv(indio_dev);
+
switch (mask) {
case IIO_CHAN_INFO_INT_TIME:
- *vals = (int *)&veml3235_it_times;
- *length = 2 * ARRAY_SIZE(veml3235_it_times);
- *type = IIO_VAL_INT_PLUS_MICRO;
- return IIO_AVAIL_LIST;
+ return iio_gts_avail_times(&data->gts, vals, type, length);
case IIO_CHAN_INFO_SCALE:
- *vals = (int *)&veml3235_scale_vals;
- *length = ARRAY_SIZE(veml3235_scale_vals);
- *type = IIO_VAL_INT;
- return IIO_AVAIL_LIST;
+ return iio_gts_all_avail_scales(&data->gts, vals, type, length);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int veml3235_write_raw_get_fmt(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ return IIO_VAL_INT_PLUS_NANO;
+ case IIO_CHAN_INFO_INT_TIME:
+ return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
@@ -309,9 +323,12 @@ static int veml3235_write_raw(struct iio_dev *indio_dev,
{
switch (mask) {
case IIO_CHAN_INFO_INT_TIME:
- return veml3235_set_it(indio_dev, val, val2);
+ if (val)
+ return -EINVAL;
+
+ return veml3235_set_it(indio_dev, val2);
case IIO_CHAN_INFO_SCALE:
- return veml3235_set_gain(indio_dev, val, val2);
+ return veml3235_set_scale(indio_dev, val, val2);
}
return -EINVAL;
@@ -321,7 +338,7 @@ static void veml3235_read_id(struct veml3235_data *data)
{
int ret, reg;
- ret = regmap_field_read(data->rf.id, ®);
+ ret = regmap_field_read(data->rf.id, ®);
if (ret) {
dev_info(data->dev, "failed to read ID\n");
return;
@@ -371,6 +388,13 @@ static int veml3235_hw_init(struct iio_dev *indio_dev)
struct device *dev = data->dev;
int ret;
+ ret = devm_iio_init_iio_gts(data->dev, 0, 272640000,
+ veml3235_gain_sel, ARRAY_SIZE(veml3235_gain_sel),
+ veml3235_it_sel, ARRAY_SIZE(veml3235_it_sel),
+ &data->gts);
+ if (ret)
+ return dev_err_probe(data->dev, ret, "failed to init iio gts\n");
+
/* Set gain to 1 and integration time to 100 ms */
ret = regmap_field_write(data->rf.gain, 0x00);
if (ret)
@@ -389,9 +413,10 @@ static int veml3235_hw_init(struct iio_dev *indio_dev)
}
static const struct iio_info veml3235_info = {
- .read_raw = veml3235_read_raw,
- .read_avail = veml3235_read_avail,
+ .read_raw = veml3235_read_raw,
+ .read_avail = veml3235_read_avail,
.write_raw = veml3235_write_raw,
+ .write_raw_get_fmt = veml3235_write_raw_get_fmt,
};
static int veml3235_probe(struct i2c_client *client)
@@ -493,3 +518,4 @@ module_i2c_driver(veml3235_driver);
MODULE_AUTHOR("Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>");
MODULE_DESCRIPTION("VEML3235 Ambient Light Sensor");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("IIO_GTS_HELPER");
--
2.43.0
