aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/iio
diff options
context:
space:
mode:
authorHui Liu <hui.liu@mediatek.com>2021-09-26 15:30:28 +0800
committerJonathan Cameron <Jonathan.Cameron@huawei.com>2021-09-26 12:30:09 +0100
commitc2980c64c7fd4585d684574c92d1624d44961edd (patch)
treee0c1e7e038954bdf3552c1c90cd11c33b5807dac /drivers/iio
parentiio: adis16475: fix deadlock on frequency set (diff)
downloadlinux-dev-c2980c64c7fd4585d684574c92d1624d44961edd.tar.xz
linux-dev-c2980c64c7fd4585d684574c92d1624d44961edd.zip
iio: mtk-auxadc: fix case IIO_CHAN_INFO_PROCESSED
The previous driver does't apply the necessary scaling to take the voltage range into account. We change readback value from raw data to input voltage to fix case IIO_CHAN_INFO_PROCESSED. Fixes: ace4cdfe67be ("iio: adc: mt2701: Add Mediatek auxadc driver for mt2701.") Signed-off-by: Hui Liu <hui.liu@mediatek.com> Link: https://lore.kernel.org/r/20210926073028.11045-2-hui.liu@mediatek.com Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio')
-rw-r--r--drivers/iio/adc/mt6577_auxadc.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/iio/adc/mt6577_auxadc.c b/drivers/iio/adc/mt6577_auxadc.c
index 79c1dd68b909..d4fccd52ef08 100644
--- a/drivers/iio/adc/mt6577_auxadc.c
+++ b/drivers/iio/adc/mt6577_auxadc.c
@@ -82,6 +82,10 @@ static const struct iio_chan_spec mt6577_auxadc_iio_channels[] = {
MT6577_AUXADC_CHANNEL(15),
};
+/* For Voltage calculation */
+#define VOLTAGE_FULL_RANGE 1500 /* VA voltage */
+#define AUXADC_PRECISE 4096 /* 12 bits */
+
static int mt_auxadc_get_cali_data(int rawdata, bool enable_cali)
{
return rawdata;
@@ -191,6 +195,10 @@ static int mt6577_auxadc_read_raw(struct iio_dev *indio_dev,
}
if (adc_dev->dev_comp->sample_data_cali)
*val = mt_auxadc_get_cali_data(*val, true);
+
+ /* Convert adc raw data to voltage: 0 - 1500 mV */
+ *val = *val * VOLTAGE_FULL_RANGE / AUXADC_PRECISE;
+
return IIO_VAL_INT;
default: