[patch 14/21] usb-audio: work around wrong frequency in CM6501 descriptors

Greg KH
2007-02-21T01:40:12Z

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

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[PATCH] usb-audio: work around wrong frequency in CM6501 descriptors

The C-Media CM6501 chip's descriptors say that altsetting 5 supports
48 kHz, but it actually plays at 96 kHz.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
sound/usb/usbaudio.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

--- linux-2.6.19.4.orig/sound/usb/usbaudio.c
+++ linux-2.6.19.4/sound/usb/usbaudio.c
@@ -2471,7 +2471,13 @@ static int parse_audio_format_rates(stru
fp->nr_rates = nr_rates;
fp->rate_min = fp->rate_max = combine_triple(&fmt[8]);
for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
- unsigned int rate = fp->rate_table[r] = combine_triple(&fmt[idx]);
+ unsigned int rate = combine_triple(&fmt[idx]);
+ /* 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;
if (rate < fp->rate_min)
fp->rate_min = rate;
else if (rate > fp->rate_max)

--