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path: root/drivers/iio/light/vl6180.c
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Diffstat (limited to 'drivers/iio/light/vl6180.c')
-rw-r--r--drivers/iio/light/vl6180.c127
1 files changed, 69 insertions, 58 deletions
diff --git a/drivers/iio/light/vl6180.c b/drivers/iio/light/vl6180.c
index 6e25b724d941..192c77ef3608 100644
--- a/drivers/iio/light/vl6180.c
+++ b/drivers/iio/light/vl6180.c
@@ -24,6 +24,7 @@
#include <linux/err.h>
#include <linux/of.h>
#include <linux/delay.h>
+#include <linux/util_macros.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
@@ -86,6 +87,8 @@
struct vl6180_data {
struct i2c_client *client;
struct mutex lock;
+ unsigned int als_gain_milli;
+ unsigned int als_it_ms;
};
enum { VL6180_ALS, VL6180_RANGE, VL6180_PROX };
@@ -275,19 +278,17 @@ static const struct iio_chan_spec vl6180_channels[] = {
};
/*
- * Columns 3 & 4 represent the same value in decimal and hex notations.
- * Kept in order to avoid the datatype conversion while reading the
- * hardware_gain.
+ * Available Ambient Light Sensor gain settings, 1/1000th, and
+ * corresponding setting for the VL6180_ALS_GAIN register
*/
-static const int vl6180_als_gain[8][4] = {
- { 1, 0, 70, VL6180_ALS_GAIN_1 },
- { 1, 250000, 69, VL6180_ALS_GAIN_1_25 },
- { 1, 670000, 68, VL6180_ALS_GAIN_1_67 },
- { 2, 500000, 67, VL6180_ALS_GAIN_2_5 },
- { 5, 0, 66, VL6180_ALS_GAIN_5 },
- { 10, 0, 65, VL6180_ALS_GAIN_10 },
- { 20, 0, 64, VL6180_ALS_GAIN_20 },
- { 40, 0, 71, VL6180_ALS_GAIN_40 }
+static const int vl6180_als_gain_tab[8] = {
+ 1000, 1250, 1670, 2500, 5000, 10000, 20000, 40000
+};
+static const u8 vl6180_als_gain_tab_bits[8] = {
+ VL6180_ALS_GAIN_1, VL6180_ALS_GAIN_1_25,
+ VL6180_ALS_GAIN_1_67, VL6180_ALS_GAIN_2_5,
+ VL6180_ALS_GAIN_5, VL6180_ALS_GAIN_10,
+ VL6180_ALS_GAIN_20, VL6180_ALS_GAIN_40
};
static int vl6180_read_raw(struct iio_dev *indio_dev,
@@ -295,7 +296,7 @@ static int vl6180_read_raw(struct iio_dev *indio_dev,
int *val, int *val2, long mask)
{
struct vl6180_data *data = iio_priv(indio_dev);
- int ret, i;
+ int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
@@ -306,19 +307,20 @@ static int vl6180_read_raw(struct iio_dev *indio_dev,
return IIO_VAL_INT;
case IIO_CHAN_INFO_INT_TIME:
- ret = vl6180_read_word(data->client, VL6180_ALS_IT);
- if (ret < 0)
- return ret;
- *val = 0; /* 1 count = 1ms (0 = 1ms) */
- *val2 = (ret + 1) * 1000; /* convert to seconds */
+ *val = data->als_it_ms;
+ *val2 = 1000;
+
+ return IIO_VAL_FRACTIONAL;
- return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_LIGHT:
- *val = 0; /* one ALS count is 0.32 Lux */
- *val2 = 320000;
- break;
+ /* one ALS count is 0.32 Lux @ gain 1, IT 100 ms */
+ *val = 32000; /* 0.32 * 1000 * 100 */
+ *val2 = data->als_gain_milli * data->als_it_ms;
+
+ return IIO_VAL_FRACTIONAL;
+
case IIO_DISTANCE:
*val = 0; /* sensor reports mm, scale to meter */
*val2 = 1000;
@@ -329,17 +331,11 @@ static int vl6180_read_raw(struct iio_dev *indio_dev,
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_HARDWAREGAIN:
- ret = vl6180_read_byte(data->client, VL6180_ALS_GAIN);
- if (ret < 0)
- return -EINVAL;
- for (i = 0; i < ARRAY_SIZE(vl6180_als_gain); i++) {
- if (ret == vl6180_als_gain[i][2]) {
- *val = vl6180_als_gain[i][0];
- *val2 = vl6180_als_gain[i][1];
- }
- }
+ *val = data->als_gain_milli;
+ *val2 = 1000;
+
+ return IIO_VAL_FRACTIONAL;
- return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
@@ -365,37 +361,53 @@ static int vl6180_hold(struct vl6180_data *data, bool hold)
static int vl6180_set_als_gain(struct vl6180_data *data, int val, int val2)
{
- int i, ret;
-
- for (i = 0; i < ARRAY_SIZE(vl6180_als_gain); i++) {
- if (val == vl6180_als_gain[i][0] &&
- val2 == vl6180_als_gain[i][1]) {
- mutex_lock(&data->lock);
- ret = vl6180_hold(data, true);
- if (ret < 0)
- goto fail;
- ret = vl6180_write_byte(data->client, VL6180_ALS_GAIN,
- vl6180_als_gain[i][3]);
-fail:
- vl6180_hold(data, false);
- mutex_unlock(&data->lock);
- return ret;
- }
- }
+ int i, ret, gain;
- return -EINVAL;
+ if (val < 1 || val > 40)
+ return -EINVAL;
+
+ gain = (val * 1000000 + val2) / 1000;
+ if (gain < 1 || gain > 40000)
+ return -EINVAL;
+
+ i = find_closest(gain, vl6180_als_gain_tab,
+ ARRAY_SIZE(vl6180_als_gain_tab));
+
+ mutex_lock(&data->lock);
+ ret = vl6180_hold(data, true);
+ if (ret < 0)
+ goto fail;
+
+ ret = vl6180_write_byte(data->client, VL6180_ALS_GAIN,
+ vl6180_als_gain_tab_bits[i]);
+
+ if (ret >= 0)
+ data->als_gain_milli = vl6180_als_gain_tab[i];
+
+fail:
+ vl6180_hold(data, false);
+ mutex_unlock(&data->lock);
+ return ret;
}
-static int vl6180_set_it(struct vl6180_data *data, int val2)
+static int vl6180_set_it(struct vl6180_data *data, int val, int val2)
{
- int ret;
+ int ret, it_ms;
+
+ it_ms = (val2 + 500) / 1000; /* round to ms */
+ if (val != 0 || it_ms < 1 || it_ms > 512)
+ return -EINVAL;
mutex_lock(&data->lock);
ret = vl6180_hold(data, true);
if (ret < 0)
goto fail;
- ret = vl6180_write_word(data->client, VL6180_ALS_IT,
- (val2 - 500) / 1000); /* write value in ms */
+
+ ret = vl6180_write_word(data->client, VL6180_ALS_IT, it_ms - 1);
+
+ if (ret >= 0)
+ data->als_it_ms = it_ms;
+
fail:
vl6180_hold(data, false);
mutex_unlock(&data->lock);
@@ -411,10 +423,8 @@ static int vl6180_write_raw(struct iio_dev *indio_dev,
switch (mask) {
case IIO_CHAN_INFO_INT_TIME:
- if (val != 0 || val2 < 500 || val2 >= 512500)
- return -EINVAL;
+ return vl6180_set_it(data, val, val2);
- return vl6180_set_it(data, val2);
case IIO_CHAN_INFO_HARDWAREGAIN:
if (chan->type != IIO_LIGHT)
return -EINVAL;
@@ -429,7 +439,6 @@ static const struct iio_info vl6180_info = {
.read_raw = vl6180_read_raw,
.write_raw = vl6180_write_raw,
.attrs = &vl6180_attribute_group,
- .driver_module = THIS_MODULE,
};
static int vl6180_init(struct vl6180_data *data)
@@ -468,11 +477,13 @@ static int vl6180_init(struct vl6180_data *data)
return ret;
/* ALS integration time: 100ms */
+ data->als_it_ms = 100;
ret = vl6180_write_word(client, VL6180_ALS_IT, VL6180_ALS_IT_100);
if (ret < 0)
return ret;
/* ALS gain: 1 */
+ data->als_gain_milli = 1000;
ret = vl6180_write_byte(client, VL6180_ALS_GAIN, VL6180_ALS_GAIN_1);
if (ret < 0)
return ret;
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