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| author | Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> | 2015-08-14 17:19:43 -0500 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2015-08-16 08:48:47 +0200 |
| commit | 395ae54bd8775508a9616817188cabbcd6f53260 (patch) | |
| tree | de6bdb631be10f249c341ee86c056d6a00ae6f97 /sound/usb | |
| parent | 630184477e7eccb2b31ee4c20b6905ca5fa4b3a8 (diff) | |
| download | blackbird-op-linux-395ae54bd8775508a9616817188cabbcd6f53260.tar.gz blackbird-op-linux-395ae54bd8775508a9616817188cabbcd6f53260.zip | |
ALSA: usb: handle descriptor with SYNC_NONE illegal value
The M-Audio Transit exposes an interface with a SYNC_NONE attribute.
This is not a valid value according to the USB audio classspec. However
there is a sync endpoint associated to this record. Changing the logic to
try to use this sync endpoint allows for seamless transitions between
altset 2 and altset 3. If any errors happen, the behavior remains the same.
$ more /proc/asound/card1/stream0
M-Audio Transit USB at usb-0000:00:14.0-2, full speed : USB Audio
Playback:
Status: Stop
Interface 1
Altset 1
Format: S24_3LE
Channels: 2
Endpoint: 3 OUT (ADAPTIVE)
Rates: 48001 - 96000 (continuous)
Interface 1
Altset 2
Format: S24_3LE
Channels: 2
Endpoint: 3 OUT (NONE)
Rates: 8000 - 48000 (continuous)
Interface 1
Altset 3
Format: S16_LE
Channels: 2
Endpoint: 3 OUT (ASYNC)
Rates: 8000 - 48000 (continuous)
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb')
| -rw-r--r-- | sound/usb/pcm.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index 7fb17c8eb49d..30797269d5aa 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -412,10 +412,17 @@ static int set_sync_endpoint(struct snd_usb_substream *subs, if (altsd->bNumEndpoints < 2) return 0; - if ((is_playback && attr != USB_ENDPOINT_SYNC_ASYNC) || + if ((is_playback && (attr == USB_ENDPOINT_SYNC_SYNC || + attr == USB_ENDPOINT_SYNC_ADAPTIVE)) || (!is_playback && attr != USB_ENDPOINT_SYNC_ADAPTIVE)) return 0; + /* + * In case of illegal SYNC_NONE for OUT endpoint, we keep going to see + * if we don't find a sync endpoint, as on M-Audio Transit. In case of + * error fall back to SYNC mode and don't create sync endpoint + */ + /* check sync-pipe endpoint */ /* ... and check descriptor size before accessing bSynchAddress because there is a version of the SB Audigy 2 NX firmware lacking @@ -429,6 +436,8 @@ static int set_sync_endpoint(struct snd_usb_substream *subs, get_endpoint(alts, 1)->bmAttributes, get_endpoint(alts, 1)->bLength, get_endpoint(alts, 1)->bSynchAddress); + if (is_playback && attr == USB_ENDPOINT_SYNC_NONE) + return 0; return -EINVAL; } ep = get_endpoint(alts, 1)->bEndpointAddress; @@ -439,6 +448,8 @@ static int set_sync_endpoint(struct snd_usb_substream *subs, "%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n", fmt->iface, fmt->altsetting, is_playback, ep, get_endpoint(alts, 0)->bSynchAddress); + if (is_playback && attr == USB_ENDPOINT_SYNC_NONE) + return 0; return -EINVAL; } @@ -450,8 +461,11 @@ static int set_sync_endpoint(struct snd_usb_substream *subs, implicit_fb ? SND_USB_ENDPOINT_TYPE_DATA : SND_USB_ENDPOINT_TYPE_SYNC); - if (!subs->sync_endpoint) + if (!subs->sync_endpoint) { + if (is_playback && attr == USB_ENDPOINT_SYNC_NONE) + return 0; return -EINVAL; + } subs->data_endpoint->sync_master = subs->sync_endpoint; |
