[alsa-devel] [PATCH v2 2/9] ALSA: hda - add helper to get channels from cap bits

[Takashi Iwai]

On Tue, 12 Apr 2016 11:56:10 +0200,
Subhransu S. Prusty wrote:
> 
> This helper is copied from legacy hda driver.
> 
> Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty at intel.com>
> Signed-off-by: Vinod Koul <vinod.koul at intel.com>
> ---
>  sound/hda/local.h | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/sound/hda/local.h b/sound/hda/local.h
> index d692f41..57f07d7 100644
> --- a/sound/hda/local.h
> +++ b/sound/hda/local.h
> @@ -16,6 +16,16 @@ static inline int get_wcaps_type(unsigned int wcaps)
>  	return (wcaps & AC_WCAP_TYPE) >> AC_WCAP_TYPE_SHIFT;
>  }
>  
> +static inline unsigned int get_wcaps_channels(u32 wcaps)
> +{
> +	unsigned int chans;
> +
> +	chans = (wcaps & AC_WCAP_CHAN_CNT_EXT) >> 13;
> +	chans = ((chans << 1) | 1) + 1;

Let's make it simple.  This is equivalent with
	chans = (chans + 1) * 2;


Takashi