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    SubjectRe: [PATCH 02/11] ASoC: ab8500: Revert back to find_next_bit()
    > > 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. :(

    > > Although this implementation may not be portable, the alternative
    > > breaks audio on anything using the AB8500 CODEC, which is a much
    > > greater evil. Besides, this driver will never run on anything
    > > else.
    > >
    > > Cc: Takashi Iwai <tiwai@suse.de>
    > > Signed-off-by: Lee Jones <lee.jones@linaro.org>
    > > ---
    > > sound/soc/codecs/ab8500-codec.c | 4 ++--
    > > 1 file changed, 2 insertions(+), 2 deletions(-)
    > >
    > > diff --git a/sound/soc/codecs/ab8500-codec.c b/sound/soc/codecs/ab8500-codec.c
    > > index 1ad92cb..51ae3e9 100644
    > > --- a/sound/soc/codecs/ab8500-codec.c
    > > +++ b/sound/soc/codecs/ab8500-codec.c
    > > @@ -2322,7 +2322,7 @@ static int ab8500_codec_set_dai_tdm_slot(struct snd_soc_dai *dai,
    > > slot = ffs(tx_mask);
    > > snd_soc_update_bits(codec, AB8500_DASLOTCONF1, mask, slot);
    > > snd_soc_update_bits(codec, AB8500_DASLOTCONF3, mask, slot);
    > > - slot = fls(tx_mask);
    > > + slot = find_next_bit((unsigned long *)&tx_mask, 32, slot + 1);
    > > snd_soc_update_bits(codec, AB8500_DASLOTCONF2, mask, slot);
    > > snd_soc_update_bits(codec, AB8500_DASLOTCONF4, mask, slot);
    > > break;
    > > @@ -2364,7 +2364,7 @@ static int ab8500_codec_set_dai_tdm_slot(struct snd_soc_dai *dai,
    > > AB8500_ADSLOTSEL(slot),
    > > AB8500_MASK_SLOT(slot),
    > > AB8500_ADSLOTSELX_AD_OUT_TO_SLOT(AB8500_AD_OUT3, slot));
    > > - slot = fls(rx_mask);
    > > + slot = find_next_bit((unsigned long *)&rx_mask, 32, slot + 1);
    > > snd_soc_update_bits(codec,
    > > AB8500_ADSLOTSEL(slot),
    > > AB8500_MASK_SLOT(slot),

    --
    Lee Jones
    Linaro STMicroelectronics Landing Team Lead
    Linaro.org │ Open source software for ARM SoCs
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