diff options
| author | Clemens Ladisch <clemens@ladisch.de> | 2005-05-02 08:53:46 +0200 |
|---|---|---|
| committer | Jaroslav Kysela <perex@suse.cz> | 2005-05-29 10:05:54 +0200 |
| commit | 1149a64fe4916fe6fdc8938043a0dc9a6551ab63 (patch) | |
| tree | fc27fcf75435d8fb856e572018fc964382e3deb7 /sound/usb/usbaudio.c | |
| parent | 4dc40a3cc4778ebcb6212bdb71b48690a153be07 (diff) | |
[ALSA] usb-audio - use proper interval between synchronization packets
USB generic driver
Add sanity checks when reading the bRefresh value, and actually use it
for the synchronization packets instead of polling at 1000 Hz.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Diffstat (limited to 'sound/usb/usbaudio.c')
| -rw-r--r-- | sound/usb/usbaudio.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c index e759b73942c..e1a648d7fff 100644 --- a/sound/usb/usbaudio.c +++ b/sound/usb/usbaudio.c @@ -1051,10 +1051,7 @@ static int init_substream_urbs(snd_usb_substream_t *subs, unsigned int period_by u->urb->pipe = subs->syncpipe; u->urb->transfer_flags = URB_ISO_ASAP; u->urb->number_of_packets = u->packets; - if (snd_usb_get_speed(subs->dev) == USB_SPEED_HIGH) - u->urb->interval = 8; - else - u->urb->interval = 1; + u->urb->interval = 1 << subs->syncinterval; u->urb->context = u; u->urb->complete = snd_usb_complete_callback(snd_complete_sync_urb); } @@ -1272,7 +1269,12 @@ static int set_format(snd_usb_substream_t *subs, struct audioformat *fmt) subs->syncpipe = usb_rcvisocpipe(dev, ep); else subs->syncpipe = usb_sndisocpipe(dev, ep); - subs->syncinterval = get_endpoint(alts, 1)->bRefresh; + if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE && + get_endpoint(alts, 1)->bRefresh >= 1 && + get_endpoint(alts, 1)->bRefresh <= 9) + subs->syncinterval = get_endpoint(alts, 1)->bRefresh; + else + subs->syncinterval = 1; } /* always fill max packet size */ |