From: Krzysztof Helt Date: Sat, 19 Dec 2009 17:31:04 +0000 (+0100) Subject: ALSA: fix incorrect rounding direction in snd_interval_ratnum() X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=40962d7c741de1c21b6ce8516c1d9f8836fb383e;p=openwrt%2Fstaging%2Fblogic.git ALSA: fix incorrect rounding direction in snd_interval_ratnum() The direction of rounding is incorrect in the snd_interval_ratnum() It was detected with following parameters (sb8 driver playing 8kHz stereo file): - num is always 1000000 - requested frequency rate is from 7999 to 7999 (single frequency) The first loop calculates div_down(num, freq->min) which is 125. Thus, a frequency range's minimum value is 1000000 / 125 = 8000 Hz. The second loop calculates div_up(num, freq->max) which is 126 The frequency range's maximum value is 1000000 / 126 = 7936 Hz. The range maximum is lower than the range minimum so the function fails due to empty result range. Signed-off-by: Krzysztof Helt Signed-off-by: Takashi Iwai --- diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 30f410832a25..a27545b23ee9 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -758,7 +758,7 @@ int snd_interval_ratnum(struct snd_interval *i, int diff; if (q == 0) q = 1; - den = div_down(num, q); + den = div_up(num, q); if (den < rats[k].den_min) continue; if (den > rats[k].den_max) @@ -794,7 +794,7 @@ int snd_interval_ratnum(struct snd_interval *i, i->empty = 1; return -EINVAL; } - den = div_up(num, q); + den = div_down(num, q); if (den > rats[k].den_max) continue; if (den < rats[k].den_min)