[PATCH] ASoC: codec: wm9860: avoid maybe-uninitialized warning

From: Arnd Bergmann
Date: Wed Apr 19 2017 - 13:05:16 EST


The new PLL configuration code triggers a harmless warning:

sound/soc/codecs/wm8960.c: In function 'wm8960_configure_clocking':
sound/soc/codecs/wm8960.c:735:3: error: 'best_freq_out' may be used uninitialized in this function [-Werror=maybe-uninitialized]
wm8960_set_pll(codec, freq_in, best_freq_out);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/soc/codecs/wm8960.c:699:12: note: 'best_freq_out' was declared here

I think the warning was introduced by Daniel's bugfix. I've come up
with a way to simplify the code in a way that is more readable to
both humans and to gcc, which gets us rid of the warning.

Fixes: 84fdc00d519f ("ASoC: codec: wm9860: Refactor PLL out freq search")
Fixes: 303e8954af8d ("ASoC: codec: wm8960: Stop when a matching PLL freq is found")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
sound/soc/codecs/wm8960.c | 25 ++++++++-----------------
1 file changed, 8 insertions(+), 17 deletions(-)

diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c
index ace69da97cb8..ba0f80504c6b 100644
--- a/sound/soc/codecs/wm8960.c
+++ b/sound/soc/codecs/wm8960.c
@@ -696,14 +696,12 @@ 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;
int i, j, k;

bclk = wm8960->bclk;
lrclk = wm8960->lrclk;

- *bclk_idx = -1;
-
for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) {
if (sysclk_divs[i] == -1)
continue;
@@ -720,22 +718,14 @@ int wm8960_configure_pll(struct snd_soc_codec *codec, int freq_in,
*sysclk_idx = i;
*dac_idx = j;
*bclk_idx = k;
- best_freq_out = freq_out;
- break;
+ return freq_out;
}
}
- if (k != ARRAY_SIZE(bclk_divs))
- break;
}
- if (j != ARRAY_SIZE(dac_divs))
- break;
}
-
- if (*bclk_idx != -1)
- wm8960_set_pll(codec, freq_in, best_freq_out);
-
- return *bclk_idx;
+ return -EINVAL;
}
+
static int wm8960_configure_clocking(struct snd_soc_codec *codec)
{
struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
@@ -783,11 +773,12 @@ static int wm8960_configure_clocking(struct snd_soc_codec *codec)
}
}

- ret = wm8960_configure_pll(codec, freq_in, &i, &j, &k);
- if (ret < 0) {
+ freq_out = wm8960_configure_pll(codec, freq_in, &i, &j, &k);
+ if (freq_out < 0) {
dev_err(codec->dev, "failed to configure clock via PLL\n");
- return -EINVAL;
+ return freq_out;
}
+ wm8960_set_pll(codec, freq_in, freq_out);

configure_clock:
/* configure sysclk clock */
--
2.9.0