AINCOM should actually be a supply. If present and it has a non-zero
voltage, the pseudo-differential channels are configured as single-ended
with an offset. Otherwise, they are configured as differential channels
between AINx and AINCOM pins.
Signed-off-by: Alisa-Dariana Roman <alisa.roman@xxxxxxxxxx>
---
drivers/iio/adc/ad7192.c | 53 +++++++++++++++++++++++++++++++++++++---
1 file changed, 49 insertions(+), 4 deletions(-)
diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c
index ac737221beae..a9eb4fab39ca 100644
--- a/drivers/iio/adc/ad7192.c
+++ b/drivers/iio/adc/ad7192.c
@@ -175,7 +175,7 @@ enum {
struct ad7192_chip_info {
unsigned int chip_id;
const char *name;
- const struct iio_chan_spec *channels;
+ struct iio_chan_spec *channels;
u8 num_channels;
const struct iio_info *info;
};
@@ -186,6 +186,7 @@ struct ad7192_state {
struct regulator *vref;
struct clk *mclk;
u16 int_vref_mv;
+ u16 aincom_mv;
u32 fclk;
u32 mode;
u32 conf;
@@ -745,6 +746,9 @@ static int ad7192_read_raw(struct iio_dev *indio_dev,
/* Kelvin to Celsius */
if (chan->type == IIO_TEMP)
*val -= 273 * ad7192_get_temp_scale(unipolar);
+ else if (st->aincom_mv && chan->channel2 == -1)
+ *val += DIV_ROUND_CLOSEST_ULL((u64)st->aincom_mv * 1000000000,
+ st->scale_avail[gain][1]);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SAMP_FREQ:
*val = DIV_ROUND_CLOSEST(ad7192_get_f_adc(st), 1024);
@@ -982,7 +986,7 @@ static const struct iio_info ad7195_info = {
#define AD7193_CHANNEL(_si, _channel1, _address) \
AD7193_DIFF_CHANNEL(_si, _channel1, -1, _address)
-static const struct iio_chan_spec ad7192_channels[] = {
+static struct iio_chan_spec ad7192_channels[] = {
AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M),
AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M),
AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP),
@@ -994,7 +998,7 @@ static const struct iio_chan_spec ad7192_channels[] = {
IIO_CHAN_SOFT_TIMESTAMP(8),
};
-static const struct iio_chan_spec ad7193_channels[] = {
+static struct iio_chan_spec ad7193_channels[] = {
AD7193_DIFF_CHANNEL(0, 1, 2, AD7193_CH_AIN1P_AIN2M),
AD7193_DIFF_CHANNEL(1, 3, 4, AD7193_CH_AIN3P_AIN4M),
AD7193_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M),
@@ -1048,11 +1052,27 @@ static void ad7192_reg_disable(void *reg)
regulator_disable(reg);
}
+static int ad7192_config_channels(struct ad7192_state *st)
+{
+ struct iio_chan_spec *channels = st->chip_info->channels;
+ int i;
+
+ if (!st->aincom_mv)
+ for (i = 0; i < st->chip_info->num_channels; i++)
+ if (channels[i].channel2 == -1) {
+ channels[i].differential = 1;
+ channels[i].channel2 = 0;
+ }
+
+ return 0;
+}
+
static int ad7192_probe(struct spi_device *spi)
{
struct ad7192_state *st;
struct iio_dev *indio_dev;
- int ret;
+ struct regulator *aincom;
+ int ret = 0;
if (!spi->irq) {
dev_err(&spi->dev, "no IRQ?\n");
@@ -1067,6 +1087,26 @@ static int ad7192_probe(struct spi_device *spi)
mutex_init(&st->lock);
+ aincom = devm_regulator_get_optional(&spi->dev, "aincom");
+ if (!IS_ERR(aincom)) {
+ ret = regulator_enable(aincom);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to enable specified AINCOM supply\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, aincom);
+ if (ret)
+ return ret;
+
+ ret = regulator_get_voltage(aincom);
+ if (ret < 0)
+ return dev_err_probe(&spi->dev, ret,
+ "Device tree error, AINCOM voltage undefined\n");
+ }
+
+ st->aincom_mv = ret / 1000;
+
st->avdd = devm_regulator_get(&spi->dev, "avdd");
if (IS_ERR(st->avdd))
return PTR_ERR(st->avdd);
@@ -1113,6 +1153,11 @@ static int ad7192_probe(struct spi_device *spi)
st->int_vref_mv = ret / 1000;
st->chip_info = spi_get_device_match_data(spi);
+
+ ret = ad7192_config_channels(st);
+ if (ret)
+ return ret;
+
indio_dev->name = st->chip_info->name;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = st->chip_info->channels;
--
2.34.1
