Re: [PATCH] iio: querying buffer scan_mask should return 0/1

[Jonathan Cameron <jic23@kernel.org>]

Ah, an obscure platform used by hardly anyone ;)

Oops.

Given timing this will be post the merge window, but I'll mark it for stable.

On 19/03/14 21:33, Alec Berg wrote:
> I'm using x86, not sure what other architectures, if any, that it affects.
>
> Thanks.
>
>
> On Wed, Mar 19, 2014 at 1:31 PM, Jonathan Cameron <jic23@kernel.org <mailto:jic23@kernel.org>> wrote:
>
>
>
>     On March 19, 2014 6:50:44 PM GMT+00:00, Alec Berg <alecaberg@chromium.org <mailto:alecaberg@chromium.org>> wrote:
>      >Ensure that querying the IIO buffer scan_mask returns a value of
>      >0 or 1. Currently querying the scan mask has the value returned
>      >by test_bit(), which returns either true or false. For some
>      >architectures test_bit() may return -1 for true, which will appear
>      >to return an error when returning from iio_scan_mask_query().
>     I'm curious now.  Which architectures?  Change is fine BTW. Will pick when I get a few mins...
>      >
>      >Additionally, it's important for the sysfs interface to consistently
>      >return the same thing when querying the scan_mask.
>      >
>      >Signed-off-by: Alec Berg <alecaberg@chromium.org <mailto:alecaberg@chromium.org>>
>      >---
>      > drivers/iio/industrialio-buffer.c | 6 ++++--
>      > 1 file changed, 4 insertions(+), 2 deletions(-)
>      >
>      >diff --git a/drivers/iio/industrialio-buffer.c
>      >b/drivers/iio/industrialio-buffer.c
>      >index c67d83b..fe25042 100644
>      >--- a/drivers/iio/industrialio-buffer.c
>      >+++ b/drivers/iio/industrialio-buffer.c
>      >@@ -165,7 +165,8 @@ static ssize_t iio_scan_el_show(struct device *dev,
>      >       int ret;
>      >       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
>      >
>      >-      ret = test_bit(to_iio_dev_attr(attr)->address,
>      >+      /* Ensure ret is 0 or 1. */
>      >+      ret = !!test_bit(to_iio_dev_attr(attr)->address,
>      >                      indio_dev->buffer->scan_mask);
>      >
>      >       return sprintf(buf, "%d\n", ret);
>      >@@ -866,7 +867,8 @@ int iio_scan_mask_query(struct iio_dev *indio_dev,
>      >       if (!buffer->scan_mask)
>      >               return 0;
>      >
>      >-      return test_bit(bit, buffer->scan_mask);
>      >+      /* Ensure return value is 0 or 1. */
>      >+      return !!test_bit(bit, buffer->scan_mask);
>      > };
>      > EXPORT_SYMBOL_GPL(iio_scan_mask_query);
>      >
>
>     --
>     Sent from my Android phone with K-9 Mail. Please excuse my brevity.
>
>