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

["Subhransu S. Prusty" <subhransu.s.prusty@intel.com>]

On Tue, Apr 12, 2016 at 12:10:48PM +0200, Takashi Iwai wrote:
> 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@intel.com>
> > Signed-off-by: Vinod Koul <vinod.koul@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;

Sure.

Regards,
Subhransu
> 
> 
> Takashi

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