On Fri, Apr 21, 2017 at 5:46 PM, Arnd Bergmann arnd@arndb.de wrote:
On Fri, Apr 21, 2017 at 3:07 PM, Daniel Baluta daniel.baluta@nxp.com wrote:
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
Fixes: 84fdc00d519f ("ASoC: codec: wm9860: Refactor PLL out freq search") Fixes: 303e8954af8d ("ASoC: codec: wm8960: Stop when a matching PLL freq is found") Suggested-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Daniel Baluta daniel.baluta@nxp.com
Arnd,
I agree that your code was more both humans and gcc anyhow for consistency with wm8960_configure_sysclk function I preferred to keep the "if(..) break" statements.
How about changing both functions the same way then?
I've tried but I couldn't find any solution. For clarity here is how the code actually looks like.
The git diff is a little bit misleading. Here is how wm8960_configure_pll code looks like:
static int wm8960_configure_pll(struct snd_soc_codec *codec, int freq_in, » » » int *sysclk_idx, int *dac_idx, int *bclk_idx) { » struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec); » int sysclk, bclk, lrclk, 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) » » » continue; » » for (j = 0; j < ARRAY_SIZE(dac_divs); ++j) { » » » sysclk = lrclk * dac_divs[j]; » » » freq_out = sysclk * sysclk_divs[i];
» » » for (k = 0; k < ARRAY_SIZE(bclk_divs); ++k) { » » » » if (!is_pll_freq_available(freq_in, freq_out)) » » » » » continue;
» » » » diff = sysclk - bclk * bclk_divs[k] / 10; » » » » if (diff == 0) { » » » » » *sysclk_idx = i; » » » » » *dac_idx = j; » » » » » *bclk_idx = k; » » » » » 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; » » } » » if (j != ARRAY_SIZE(dac_divs)) » » » break; » }
» return best_freq_out; }
In my opinion this is a compiler false positive. Any clue on how to rework this would be welcomed :). I couldn't find any decent solution.
Daniel.