iio:adc:vf610-adc: Add temperature sensor support
Vybrid ADC peripheral includes a temperature sensor
which is connected to channel number 26. This patch
adds support for the sensor. The raw value is read
and the temperature calculated in milli degree Celsius,
which is returned using IIO_CHAN_INFO_PROCESSED option.
Signed-off-by: Sanchayan Maity <maitysanchayan@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c
index 4a10ae9..7ec21b5 100644
--- a/drivers/iio/adc/vf610_adc.c
+++ b/drivers/iio/adc/vf610_adc.c
@@ -91,7 +91,7 @@
#define VF610_ADC_CAL 0x80
/* Other field define */
-#define VF610_ADC_ADCHC(x) ((x) & 0xF)
+#define VF610_ADC_ADCHC(x) ((x) & 0x1F)
#define VF610_ADC_AIEN (0x1 << 7)
#define VF610_ADC_CONV_DISABLE 0x1F
#define VF610_ADC_HS_COCO0 0x1
@@ -153,6 +153,12 @@
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
}
+#define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \
+ .type = (_chan_type), \
+ .channel = (_idx), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
+}
+
static const struct iio_chan_spec vf610_adc_iio_channels[] = {
VF610_ADC_CHAN(0, IIO_VOLTAGE),
VF610_ADC_CHAN(1, IIO_VOLTAGE),
@@ -170,6 +176,7 @@
VF610_ADC_CHAN(13, IIO_VOLTAGE),
VF610_ADC_CHAN(14, IIO_VOLTAGE),
VF610_ADC_CHAN(15, IIO_VOLTAGE),
+ VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP),
/* sentinel */
};
@@ -451,6 +458,7 @@
switch (mask) {
case IIO_CHAN_INFO_RAW:
+ case IIO_CHAN_INFO_PROCESSED:
mutex_lock(&indio_dev->mlock);
reinit_completion(&info->completion);
@@ -468,7 +476,23 @@
return ret;
}
- *val = info->value;
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ *val = info->value;
+ break;
+ case IIO_TEMP:
+ /*
+ * Calculate in degree Celsius times 1000
+ * Using sensor slope of 1.84 mV/°C and
+ * V at 25°C of 696 mV
+ */
+ *val = 25000 - ((int)info->value - 864) * 1000000 / 1840;
+ break;
+ default:
+ mutex_unlock(&indio_dev->mlock);
+ return -EINVAL;
+ }
+
mutex_unlock(&indio_dev->mlock);
return IIO_VAL_INT;