[PATCH] iio: adc: ti-ads8344: Fix channel selection

[PATCH] iio: adc: ti-ads8344: Fix channel selection

[Gregory CLEMENT]

During initial submission the selection of the channel was done using
the scan_index member of the iio_chan_spec structure. It was an abuse
because this member is supposed to be used with a buffer so it was
removed.

However there was still the need to be able to known how to select a
channel, the correct member to store this information is address.

Thanks to this it is possible to select any other channel than the
channel 0.

Fixes: 8dd2d7c0fed7 ("iio: adc: Add driver for the TI ADS8344 A/DC chips")
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
---
 drivers/iio/adc/ti-ads8344.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c
index 9a460807d46d..d384ca3437da 100644
--- a/drivers/iio/adc/ti-ads8344.c
+++ b/drivers/iio/adc/ti-ads8344.c
@@ -32,16 +32,17 @@ struct ads8344 {
 	u16 rx_buf;
 };
 
-#define ADS8344_VOLTAGE_CHANNEL(chan, si)				\
+#define ADS8344_VOLTAGE_CHANNEL(chan, addr)				\
 	{								\
 		.type = IIO_VOLTAGE,					\
 		.indexed = 1,						\
 		.channel = chan,					\
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+		.address = addr,					\
 	}
 
-#define ADS8344_VOLTAGE_CHANNEL_DIFF(chan1, chan2, si)			\
+#define ADS8344_VOLTAGE_CHANNEL_DIFF(chan1, chan2, addr)		\
 	{								\
 		.type = IIO_VOLTAGE,					\
 		.indexed = 1,						\
@@ -50,6 +51,7 @@ struct ads8344 {
 		.differential = 1,					\
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+		.address = addr,					\
 	}
 
 static const struct iio_chan_spec ads8344_channels[] = {
@@ -105,7 +107,7 @@ static int ads8344_read_raw(struct iio_dev *iio,
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		mutex_lock(&adc->lock);
-		*value = ads8344_adc_conversion(adc, channel->scan_index,
+		*value = ads8344_adc_conversion(adc, channel->address,
 						channel->differential);
 		mutex_unlock(&adc->lock);
 		if (*value < 0)
-- 
2.26.1

Re: [PATCH] iio: adc: ti-ads8344: Fix channel selection

[Jonathan Cameron]

On Thu, 30 Apr 2020 15:05:47 +0200
Gregory CLEMENT <gregory.clement@bootlin.com> wrote:

> During initial submission the selection of the channel was done using
> the scan_index member of the iio_chan_spec structure. It was an abuse
> because this member is supposed to be used with a buffer so it was
> removed.
> 
> However there was still the need to be able to known how to select a
> channel, the correct member to store this information is address.
> 
> Thanks to this it is possible to select any other channel than the
> channel 0.
> 
> Fixes: 8dd2d7c0fed7 ("iio: adc: Add driver for the TI ADS8344 A/DC chips")
> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>

Applied to the fixes-togreg branch of iio.git and marked for stable.

Oops on this one :(

Thanks,

Jonathan

> ---
>  drivers/iio/adc/ti-ads8344.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c
> index 9a460807d46d..d384ca3437da 100644
> --- a/drivers/iio/adc/ti-ads8344.c
> +++ b/drivers/iio/adc/ti-ads8344.c
> @@ -32,16 +32,17 @@ struct ads8344 {
>  	u16 rx_buf;
>  };
>  
> -#define ADS8344_VOLTAGE_CHANNEL(chan, si)				\
> +#define ADS8344_VOLTAGE_CHANNEL(chan, addr)				\
>  	{								\
>  		.type = IIO_VOLTAGE,					\
>  		.indexed = 1,						\
>  		.channel = chan,					\
>  		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
>  		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
> +		.address = addr,					\
>  	}
>  
> -#define ADS8344_VOLTAGE_CHANNEL_DIFF(chan1, chan2, si)			\
> +#define ADS8344_VOLTAGE_CHANNEL_DIFF(chan1, chan2, addr)		\
>  	{								\
>  		.type = IIO_VOLTAGE,					\
>  		.indexed = 1,						\
> @@ -50,6 +51,7 @@ struct ads8344 {
>  		.differential = 1,					\
>  		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
>  		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
> +		.address = addr,					\
>  	}
>  
>  static const struct iio_chan_spec ads8344_channels[] = {
> @@ -105,7 +107,7 @@ static int ads8344_read_raw(struct iio_dev *iio,
>  	switch (mask) {
>  	case IIO_CHAN_INFO_RAW:
>  		mutex_lock(&adc->lock);
> -		*value = ads8344_adc_conversion(adc, channel->scan_index,
> +		*value = ads8344_adc_conversion(adc, channel->address,
>  						channel->differential);
>  		mutex_unlock(&adc->lock);
>  		if (*value < 0)