Re: [PATCH v2 1/2] tools: iio: fix mask for 32 bit sensor data

From: Jonathan Cameron
Date: Sun Aug 02 2015 - 13:39:00 EST


On 24/07/15 14:28, Irina Tirdea wrote:
> When the the sensor data uses 32 bits out of 32, generic_buffer prints
> the value 0 for all data read.
>
> In this case, the mask is shifted 32 bits, which is beyond the size of
> an integer. This will lead to the mask always being 0. Before printing,
> the mask is applied to the raw value, thus generating a final value of 0.
>
> Fix the mask by shifting a 64 bit value instead of an integer.
>
> Signed-off-by: Irina Tirdea <irina.tirdea@xxxxxxxxx>
> Acked-by: Hartmut Knaack <knaack.h@xxxxxx>
Applied to the togreg branch of iio.git
Pushed out as testing for the autobuilders to completely
ignore this patch :)

Jonathan
> ---
> tools/iio/iio_utils.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/iio/iio_utils.c b/tools/iio/iio_utils.c
> index 1dcdf03..a95270f 100644
> --- a/tools/iio/iio_utils.c
> +++ b/tools/iio/iio_utils.c
> @@ -168,7 +168,7 @@ int iioutils_get_type(unsigned *is_signed, unsigned *bytes, unsigned *bits_used,
> if (*bits_used == 64)
> *mask = ~0;
> else
> - *mask = (1 << *bits_used) - 1;
> + *mask = (1ULL << *bits_used) - 1;
>
> *is_signed = (signchar == 's');
> if (fclose(sysfsfp)) {
>

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