The integration time of the veml6070 depends on an external resistor
(called Rset in the datasheet) and the value configured in the IT
field of the command register.
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
---
drivers/iio/light/veml6070.c | 109 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 107 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/light/veml6070.c b/drivers/iio/light/veml6070.c
index d11ae00f61f8..87dc3295a656 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>
@@ -29,15 +29,78 @@
#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 it[4][2];
};
+static void veml6070_calc_it(struct device *dev, struct veml6070_data *data)
+{
+ u32 rset, tmp_it;
+ int i, ret;
+
+ ret = device_property_read_u32(dev, "rset-kohms", &rset);
+ if (ret) {
+ dev_warn(dev, "no Rset specified, using default 300 kohms\n");
+ rset = 300;
+ }
+
+ if (rset < 75) {
+ dev_warn(dev, "Rset too low, using minimum = 75 kohms\n");
+ rset = 75;
+ }
+
+ if (rset > 1200) {
+ dev_warn(dev, "Rset too high, using maximum = 1200 kohms\n");
+ rset = 1200;
+ }
+
+ tmp_it = VEML6070_MIN_IT_US * (rset / VEML6070_MIN_RSET_KOHM);
+ for (i = 0; i < ARRAY_SIZE(data->it); i++) {
+ data->it[i][0] = (tmp_it << i) / 1000000;
+ data->it[i][1] = (tmp_it << i) % 1000000;
+ }
+}
+
+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;
@@ -81,10 +144,14 @@ 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),
}
};
@@ -127,6 +194,40 @@ static int veml6070_read_raw(struct iio_dev *indio_dev,
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 +235,8 @@ 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 +267,8 @@ static int veml6070_probe(struct i2c_client *client)
indio_dev->name = VEML6070_DRV_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
+ veml6070_calc_it(&client->dev, data);
+
ret = devm_regulator_get_enable(&client->dev, "vdd");
if (ret < 0)
return ret;
--
2.43.0
