[PATCH] staging:iio: Fix scan mask update

[PATCH] staging:iio: Fix scan mask update

[Lars-Peter Clausen]

When updating the scan mask we have to check the actual scan mask for if the
channel is already enabled, not the matching scan mask from the available
scan masks. The bit will already be set there and as a result the actual
scan mask will not get updated and the channel stays disabled.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/staging/iio/industrialio-buffer.c |   12 ++----------
 1 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/iio/industrialio-buffer.c b/drivers/staging/iio/industrialio-buffer.c
index f629e8b..a539c7c 100644
--- a/drivers/staging/iio/industrialio-buffer.c
+++ b/drivers/staging/iio/industrialio-buffer.c
@@ -171,7 +171,7 @@ static ssize_t iio_scan_el_store(struct device *dev,
 error_ret:
 	mutex_unlock(&indio_dev->mlock);
 
-	return ret ? ret : len;
+	return ret < 0 ? ret : len;
 
 }
 
@@ -617,16 +617,8 @@ int iio_scan_mask_query(struct iio_dev *indio_dev,
 
 	if (!buffer->scan_mask)
 		return 0;
-	if (indio_dev->available_scan_masks)
-		mask = iio_scan_mask_match(indio_dev->available_scan_masks,
-					   indio_dev->masklength,
-					   buffer->scan_mask);
-	else
-		mask = buffer->scan_mask;
-	if (!mask)
-		return 0;
 
-	return test_bit(bit, mask);
+	return test_bit(bit, buffer->scan_mask);
 };
 EXPORT_SYMBOL_GPL(iio_scan_mask_query);
 
-- 
1.7.7.3

Re: [PATCH] staging:iio: Fix scan mask update

[Jonathan Cameron]

On 12/07/2011 02:43 PM, Lars-Peter Clausen wrote:
> When updating the scan mask we have to check the actual scan mask for if the
> channel is already enabled, not the matching scan mask from the available
> scan masks. The bit will already be set there and as a result the actual
> scan mask will not get updated and the channel stays disabled.
Dratt, I messed this case up didn't I!  I guess my tests only make
changes that effect the scan mask.  Oops.

Thanks for the catch.  This is clearly a hole in my tests...

> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>

> ---
>  drivers/staging/iio/industrialio-buffer.c |   12 ++----------
>  1 files changed, 2 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/staging/iio/industrialio-buffer.c b/drivers/staging/iio/industrialio-buffer.c
> index f629e8b..a539c7c 100644
> --- a/drivers/staging/iio/industrialio-buffer.c
> +++ b/drivers/staging/iio/industrialio-buffer.c
> @@ -171,7 +171,7 @@ static ssize_t iio_scan_el_store(struct device *dev,
>  error_ret:
>  	mutex_unlock(&indio_dev->mlock);
>  
> -	return ret ? ret : len;
> +	return ret < 0 ? ret : len;
>  
>  }
>  
> @@ -617,16 +617,8 @@ int iio_scan_mask_query(struct iio_dev *indio_dev,
>  
>  	if (!buffer->scan_mask)
>  		return 0;
> -	if (indio_dev->available_scan_masks)
> -		mask = iio_scan_mask_match(indio_dev->available_scan_masks,
> -					   indio_dev->masklength,
> -					   buffer->scan_mask);
> -	else
> -		mask = buffer->scan_mask;
> -	if (!mask)
> -		return 0;
>  
> -	return test_bit(bit, mask);
> +	return test_bit(bit, buffer->scan_mask);
>  };
>  EXPORT_SYMBOL_GPL(iio_scan_mask_query);
>