> Vybrid ADC module 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 degree Celsius which is
> returned using the IIO_CHAN_INFO_PROCESSED option.
the description is wrong, should be 'milli degree Celsius'
more comments inline
> Signed-off-by: Sanchayan Maity <maitysanchayan@xxxxxxxxx>
> ---
> drivers/iio/adc/vf610_adc.c | 34 +++++++++++++++++++++++++++++++---
> 1 file changed, 31 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c
> index 44799eb5..aa682aa 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
> @@ -137,7 +137,7 @@ struct vf610_adc {
> struct clk *clk;
>
> u32 vref_uv;
> - u32 value;
> + int value;
> struct regulator *vref;
> struct vf610_adc_feature adc_feature;
>
> @@ -153,6 +153,15 @@ struct vf610_adc {
> BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> }
>
> +#define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \
there is just one temperature channel, so not indexed
> + .type = (_chan_type), \
> + .indexed = 1, \
> + .channel = (_idx), \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
no need for SCALE since temperature it is PROCESSED;
maybe it would be better to expose RAW + offset/scale
I don't see how the sampling freq. can be separately controlled for the
temperature channel
> +}
> +
> static const struct iio_chan_spec vf610_adc_iio_channels[] = {
> VF610_ADC_CHAN(0, IIO_VOLTAGE),
> VF610_ADC_CHAN(1, IIO_VOLTAGE),
> @@ -170,6 +179,7 @@ static const struct iio_chan_spec vf610_adc_iio_channels[] = {
> 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 +461,7 @@ static int vf610_read_raw(struct iio_dev *indio_dev,
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> + case IIO_CHAN_INFO_PROCESSED:
> mutex_lock(&indio_dev->mlock);
> reinit_completion(&info->completion);
>
> @@ -468,7 +479,24 @@ static int vf610_read_raw(struct iio_dev *indio_dev,
> 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 696mv
> + */
> + info->value -= 864;
> + info->value = 25000 - info->value * 1000000 / 1840;
why write info->value?
I'd leave value u32 and only read value here
*val = 25000 - (info->value - 864) * 1000000 / 1840;
> + *val = info->value;
> + break;
> + default:
this should return an error
> + break;
> + }
> +
> mutex_unlock(&indio_dev->mlock);
> return IIO_VAL_INT;
>
>
--
Peter Meerwald
+43-664-2444418 (mobile)
