2021-08-31 05:43:16

by Hui Liu

Subject: [PATCH v2 0/1] AUXADC: Mediatek auxadc driver

This series includes one patch:
1.update case IIO_CHAN_INFO_PROCESSED: convert raw data to voltage.

Changes in patch v2:
1)abandon support case IIO_CHAN_INFO_RAW.

Changes in patch v1:
1)fix typo covert to convert in patch 2/2 description.

Hui Liu (1):
iio: mtk-auxadc: update case IIO_CHAN_INFO_PROCESSED

drivers/iio/adc/mt6577_auxadc.c | 8 ++++++++
1 file changed, 8 insertions(+)

--
2.18.0

2021-08-31 05:44:16

by Hui Liu

Subject: [PATCH v2 1/1] iio: mtk-auxadc: update case IIO_CHAN_INFO_PROCESSED

Convert raw data to processed data, the processed data is input voltage.

Signed-off-by: Hui Liu <[email protected]>
---
drivers/iio/adc/mt6577_auxadc.c | 8 ++++++++
1 file changed, 8 insertions(+)

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:
--
2.18.0

2021-09-05 12:06:51

by Jonathan Cameron

Subject: Re: [PATCH v2 1/1] iio: mtk-auxadc: update case IIO_CHAN_INFO_PROCESSED

On Tue, 31 Aug 2021 13:42:07 +0800
Hui Liu <[email protected]> wrote:

> Convert raw data to processed data, the processed data is input voltage.
>
> Signed-off-by: Hui Liu <[email protected]>

Looks very much to be a fix. Please track down appropriate patch and let
me know what the Fixes: tag should be. If you reply to this thread
I'll add it plus a not saying it is an ABI change, but a necessary one
as the driver was previously buggy.

Whilst we are here, what is the cali_data() function actually there for?
Seems to only set *val = *val which is rather pointless.

Thanks,

Jonathan

> ---
> drivers/iio/adc/mt6577_auxadc.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> 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: