[alsa-devel] [PATCH 02/11] ASoC: ab8500: Revert back to find_next_bit()
lee.jones at linaro.org
Fri Dec 20 15:02:11 CET 2013
> > > > Commit '166a34d ASoC: ab8500: Fix invalid cast to long pointer'
> > > > rather carelessly converts find_next_bit() to fls() (find last
> > > > bit set), which are not the same.
> > >
> > > Does it break on the real machines?
> > It does, that's how I found the bug.
> > > fls() behaves differently from find_next_bit(), of course, but in this
> > > case, it should work same in the end, since there are at most two
> > > bits.
> > Unfortunately it doesn't work at all. This patch brings audio back to
> > a working state. It took me the best part of a day to track down the
> > issue. :(
> Hmm, then isn't the original code rather buggy?
> Check the values set there by ffs(), fls() and the original
> find_next_bit(), especially whether find_next_bit() gives a valid
> value fitting with the mask bits.
I wish I had the time to delve into exactly what's happening. All I
can tell you is your patch broke audio and this one fixes it again. If
you have time for a deep dive and produce a permanent solution I'd be
much obliged and will of course test anything you send me. In the mean
time, this patch should definitely be applied, as sound is crippled
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