[ALSA] usb-audio - high speed audio support
USB generic driver
Add support for endpoints with bInterval > 1, and decoding of the
wMaxPacketSize field of high-speed endpoints.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c
index b5e734d..facd9fc 100644
--- a/sound/usb/usbaudio.c
+++ b/sound/usb/usbaudio.c
@@ -153,6 +153,7 @@
unsigned int format; /* USB data format */
unsigned int datapipe; /* the data i/o pipe */
unsigned int syncpipe; /* 1 - async out or adaptive in */
+ unsigned int datainterval; /* log_2 of data packet interval */
unsigned int syncinterval; /* P for adaptive mode, 0 otherwise */
unsigned int freqn; /* nominal sampling rate in fs/fps in Q16.16 format */
unsigned int freqm; /* momentary sampling rate in fs/fps in Q16.16 format */
@@ -518,7 +519,8 @@
if (subs->fill_max)
counts = subs->maxframesize; /* fixed */
else {
- subs->phase = (subs->phase & 0xffff) + subs->freqm;
+ subs->phase = (subs->phase & 0xffff)
+ + (subs->freqm << subs->datainterval);
counts = subs->phase >> 16;
if (counts > subs->maxframesize)
counts = subs->maxframesize;
@@ -899,16 +901,19 @@
else
subs->freqn = get_usb_high_speed_rate(rate);
subs->freqm = subs->freqn;
- subs->freqmax = subs->freqn + (subs->freqn >> 2); /* max. allowed frequency */
- subs->phase = 0;
-
- /* calculate the max. size of packet */
- maxsize = ((subs->freqmax + 0xffff) * (frame_bits >> 3)) >> 16;
- if (subs->maxpacksize && maxsize > subs->maxpacksize) {
- //snd_printd(KERN_DEBUG "maxsize %d is greater than defined size %d\n",
- // maxsize, subs->maxpacksize);
+ /* calculate max. frequency */
+ if (subs->maxpacksize) {
+ /* whatever fits into a max. size packet */
maxsize = subs->maxpacksize;
+ subs->freqmax = (maxsize / (frame_bits >> 3))
+ << (16 - subs->datainterval);
+ } else {
+ /* no max. packet size: just take 25% higher than nominal */
+ subs->freqmax = subs->freqn + (subs->freqn >> 2);
+ maxsize = ((subs->freqmax + 0xffff) * (frame_bits >> 3))
+ >> (16 - subs->datainterval);
}
+ subs->phase = 0;
if (subs->fill_max)
subs->curpacksize = subs->maxpacksize;
@@ -918,7 +923,7 @@
if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
urb_packs = nrpacks;
else
- urb_packs = nrpacks * 8;
+ urb_packs = (nrpacks * 8) >> subs->datainterval;
/* allocate a temporary buffer for playback */
if (is_playback) {
@@ -991,7 +996,7 @@
u->urb->pipe = subs->datapipe;
u->urb->transfer_flags = URB_ISO_ASAP;
u->urb->number_of_packets = u->packets;
- u->urb->interval = 1;
+ u->urb->interval = 1 << subs->datainterval;
u->urb->context = u;
u->urb->complete = snd_usb_complete_callback(snd_complete_urb);
}
@@ -1195,6 +1200,12 @@
subs->datapipe = usb_sndisocpipe(dev, ep);
else
subs->datapipe = usb_rcvisocpipe(dev, ep);
+ if (snd_usb_get_speed(subs->dev) == USB_SPEED_HIGH &&
+ get_endpoint(alts, 0)->bInterval >= 1 &&
+ get_endpoint(alts, 0)->bInterval <= 4)
+ subs->datainterval = get_endpoint(alts, 0)->bInterval - 1;
+ else
+ subs->datainterval = 0;
subs->syncpipe = subs->syncinterval = 0;
subs->maxpacksize = fmt->maxpacksize;
subs->fill_max = 0;
@@ -2492,8 +2503,10 @@
fp->altset_idx = i;
fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
- /* FIXME: decode wMaxPacketSize of high bandwith endpoints */
fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
+ if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
+ fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
+ * (fp->maxpacksize & 0x7ff);
fp->attributes = csep[3];
/* some quirks for attributes here */