[patch 31/96] ALSA: usb-audio - Fix non-continuous rate detection

Greg KH
2009-03-14T00:29:26Z

[-- Attachment #1: alsa-usb-audio-fix-non-continuous-rate-detection.patch --]
[-- Type: text/plain, Size: 2029 bytes --]

2.6.27-stable review patch. If anyone has any objections, please let us know.

------------------

From: Takashi Iwai <tiwai@suse.de>

commit 0412558c873f716efe902b397af0653a550f7341 upstream.

The detection of non-continuous rates (given via rate tables) isn't
processed properly (e.g. for type II).

This patch fixes and simplifies the detection code.

Tested-by: Joris van Rantwijk <jorispubl@xs4all.nl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
sound/usb/usbaudio.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

--- a/sound/usb/usbaudio.c
+++ b/sound/usb/usbaudio.c
@@ -2516,7 +2516,6 @@ static int parse_audio_format_rates(stru
* build the rate table and bitmap flags
*/
int r, idx;
- unsigned int nonzero_rates = 0;

fp->rate_table = kmalloc(sizeof(int) * nr_rates, GFP_KERNEL);
if (fp->rate_table == NULL) {
@@ -2524,24 +2523,26 @@ static int parse_audio_format_rates(stru
return -1;
}

- fp->nr_rates = nr_rates;
- fp->rate_min = fp->rate_max = combine_triple(&fmt[8]);
+ fp->nr_rates = 0;
+ fp->rate_min = fp->rate_max = 0;
for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
unsigned int rate = combine_triple(&fmt[idx]);
+ if (!rate)
+ continue;
/* C-Media CM6501 mislabels its 96 kHz altsetting */
if (rate == 48000 && nr_rates == 1 &&
chip->usb_id == USB_ID(0x0d8c, 0x0201) &&
fp->altsetting == 5 && fp->maxpacksize == 392)
rate = 96000;
- fp->rate_table[r] = rate;
- nonzero_rates |= rate;
- if (rate < fp->rate_min)
+ fp->rate_table[fp->nr_rates] = rate;
+ if (!fp->rate_min || rate < fp->rate_min)
fp->rate_min = rate;
- else if (rate > fp->rate_max)
+ if (!fp->rate_max || rate > fp->rate_max)
fp->rate_max = rate;
fp->rates |= snd_pcm_rate_to_rate_bit(rate);
+ fp->nr_rates++;
}
- if (!nonzero_rates) {
+ if (!fp->nr_rates) {
hwc_debug("All rates were zero. Skipping format!\n");
return -1;
}