[ALSA] usbaudio - Fix Oops with broken usb descriptors

This is a patch for ALSA Bug #2724. Some webcams provide bogus
settings with no valid rates. With this patch those are skipped.

Signed-off-by: Gregor Jasny <gjasny@web.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
This commit is contained in:
Gregor Jasny 2007-01-31 12:27:39 +01:00 committed by Jaroslav Kysela
parent 4147dab62d
commit beb60119bc
1 changed files with 6 additions and 0 deletions

View File

@ -2463,6 +2463,7 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
* build the rate table and bitmap flags
*/
int r, idx, c;
unsigned int nonzero_rates = 0;
/* this table corresponds to the SNDRV_PCM_RATE_XXX bit */
static unsigned int conv_rates[] = {
5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
@ -2485,6 +2486,7 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
fp->altsetting == 5 && fp->maxpacksize == 392)
rate = 96000;
fp->rate_table[r] = rate;
nonzero_rates |= rate;
if (rate < fp->rate_min)
fp->rate_min = rate;
else if (rate > fp->rate_max)
@ -2500,6 +2502,10 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
if (!found)
fp->needs_knot = 1;
}
if (!nonzero_rates) {
hwc_debug("All rates were zero. Skipping format!\n");
return -1;
}
if (fp->needs_knot)
fp->rates |= SNDRV_PCM_RATE_KNOT;
} else {