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| author | Clemens Ladisch <clemens@ladisch.de> | 2005-05-13 07:44:13 +0200 |
|---|---|---|
| committer | Jaroslav Kysela <perex@suse.cz> | 2005-05-29 10:08:50 +0200 |
| commit | 50cdbf1519a891bec4ce306c7bae397a0d8e7246 (patch) | |
| tree | 17fb772a610e750e3e98e25f930143f1b784ff84 /sound/usb | |
| parent | 7291548df69ab4e3a87ff6952449d1f05c3a5443 (diff) | |
| download | lwn-50cdbf1519a891bec4ce306c7bae397a0d8e7246.tar.gz lwn-50cdbf1519a891bec4ce306c7bae397a0d8e7246.zip | |
[ALSA] usb-audio - sanity-check sync feedback frequency values
USB generic driver
Check that the synchronization feedback frequency values returned by the
device are more or less near the nominal frequency.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Diffstat (limited to 'sound/usb')
| -rw-r--r-- | sound/usb/usbaudio.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c index c360ab9783d5..a6ed0d08337e 100644 --- a/sound/usb/usbaudio.c +++ b/sound/usb/usbaudio.c @@ -452,17 +452,11 @@ static int retire_playback_sync_urb(snd_usb_substream_t *subs, if (urb->iso_frame_desc[0].status == 0 && urb->iso_frame_desc[0].actual_length == 3) { f = combine_triple((u8*)urb->transfer_buffer) << 2; -#if 0 - if (f < subs->freqn - (subs->freqn>>3) || f > subs->freqmax) { - snd_printd(KERN_WARNING "requested frequency %d (%u,%03uHz) out of range (current nominal %d (%u,%03uHz))\n", - f, f >> 14, (f & ((1 << 14) - 1) * 1000) / ((1 << 14) - 1), - subs->freqn, subs->freqn >> 14, (subs->freqn & ((1 << 14) - 1) * 1000) / ((1 << 14) - 1)); - continue; + if (f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax) { + spin_lock_irqsave(&subs->lock, flags); + subs->freqm = f; + spin_unlock_irqrestore(&subs->lock, flags); } -#endif - spin_lock_irqsave(&subs->lock, flags); - subs->freqm = f; - spin_unlock_irqrestore(&subs->lock, flags); } return 0; @@ -484,9 +478,11 @@ static int retire_playback_sync_urb_hs(snd_usb_substream_t *subs, if (urb->iso_frame_desc[0].status == 0 && urb->iso_frame_desc[0].actual_length == 4) { f = combine_quad((u8*)urb->transfer_buffer) & 0x0fffffff; - spin_lock_irqsave(&subs->lock, flags); - subs->freqm = f; - spin_unlock_irqrestore(&subs->lock, flags); + if (f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax) { + spin_lock_irqsave(&subs->lock, flags); + subs->freqm = f; + spin_unlock_irqrestore(&subs->lock, flags); + } } return 0; |