| Message ID | 1492780055-4892-3-git-send-email-daniel.baluta@nxp.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Apr 21, 2017 at 3:07 PM, Daniel Baluta <daniel.baluta@nxp.com> wrote: > Bitclk is derived from sysclk using bclk_divs. > Sysclk can be derived in two ways: > (1) directly from MLCK > (2) MCLK via PLL > > Commit 3c01b9ee2ab9d0d ("ASoC: codec: wm8960: Relax bit clock > computation") > relaxed bitclk computation when sysclk is directly derived from MCLK. > > Lets do the same thing when sysclk is derived via PLL. > > Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com> > --- > Here, I forced the following harmless initialization: > > *sysclk_idx = *dac_idx = *bclk_idx = -1; > > otherwise I would trigger a gcc false positive warning: > > sound/soc/codecs/wm8960.c: In function 'wm8960_configure_clocking': > sound/soc/codecs/wm8960.c:810:46: warning: 'j' may be used uninitialized > in this function [-Wmaybe-uninitialized] > snd_soc_update_bits(codec, WM8960_CLOCK1, 0x7 << 6, j << 6); > ~~^~~~ > sound/soc/codecs/wm8960.c:806:44: warning: 'i' may be used uninitialized > in this function [-Wmaybe-uninitialized] > snd_soc_update_bits(codec, WM8960_CLOCK1, 3 << 1, i << 1); > ~~^~~~ I saw the same warning earlier, but it was gone after the rework I posted the other day. Please try if that works for you as well, I think that would be better than a bogus initialization. Arnd
diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c index 8c87153..60700d5 100644 --- a/sound/soc/codecs/wm8960.c +++ b/sound/soc/codecs/wm8960.c @@ -679,6 +679,10 @@ int wm8960_configure_sysclk(struct wm8960_priv *wm8960, int mclk, * - freq_out = sysclk * sysclk_divs * - 10 * sysclk = bclk * bclk_divs * + * If we cannot find an exact match for (sysclk, lrclk, bclk) + * triplet, we relax the bclk such that bclk is chosen as the + * closest available frequency greater than expected bclk. + * * @codec: codec structure * @freq_in: input frequency used to derive freq out via PLL * @sysclk_idx: sysclk_divs index for found sysclk @@ -696,13 +700,15 @@ int wm8960_configure_pll(struct snd_soc_codec *codec, int freq_in, { struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec); int sysclk, bclk, lrclk, freq_out; - int diff, best_freq_out; + int diff, closest, best_freq_out; int i, j, k; bclk = wm8960->bclk; lrclk = wm8960->lrclk; + closest = freq_in; best_freq_out = -EINVAL; + *sysclk_idx = *dac_idx = *bclk_idx = -1; for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) { if (sysclk_divs[i] == -1) @@ -723,6 +729,13 @@ int wm8960_configure_pll(struct snd_soc_codec *codec, int freq_in, best_freq_out = freq_out; break; } + if (diff > 0 && closest > diff) { + *sysclk_idx = i; + *dac_idx = j; + *bclk_idx = k; + closest = diff; + best_freq_out = freq_out; + } } if (k != ARRAY_SIZE(bclk_divs)) break;
Bitclk is derived from sysclk using bclk_divs. Sysclk can be derived in two ways: (1) directly from MLCK (2) MCLK via PLL Commit 3c01b9ee2ab9d0d ("ASoC: codec: wm8960: Relax bit clock computation") relaxed bitclk computation when sysclk is directly derived from MCLK. Lets do the same thing when sysclk is derived via PLL. Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com> --- Here, I forced the following harmless initialization: *sysclk_idx = *dac_idx = *bclk_idx = -1; otherwise I would trigger a gcc false positive warning: sound/soc/codecs/wm8960.c: In function 'wm8960_configure_clocking': sound/soc/codecs/wm8960.c:810:46: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized] snd_soc_update_bits(codec, WM8960_CLOCK1, 0x7 << 6, j << 6); ~~^~~~ sound/soc/codecs/wm8960.c:806:44: warning: 'i' may be used uninitialized in this function [-Wmaybe-uninitialized] snd_soc_update_bits(codec, WM8960_CLOCK1, 3 << 1, i << 1); ~~^~~~ sound/soc/codecs/wm8960.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)