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[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>
This commit is contained in:
Clemens Ladisch 2005-06-27 08:17:30 +02:00 committed by Jaroslav Kysela
parent b0af0de5cb
commit 573567e07b
1 changed files with 25 additions and 12 deletions
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37
sound/usb/usbaudio.c
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@ -153,6 +153,7 @@ struct snd_usb_substream {
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 @@ static int prepare_playback_urb(snd_usb_substream_t *subs,
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 @@ static int init_substream_urbs(snd_usb_substream_t *subs, unsigned int period_by
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 @@ static int init_substream_urbs(snd_usb_substream_t *subs, unsigned int period_by
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 @@ static int init_substream_urbs(snd_usb_substream_t *subs, unsigned int period_by
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 @@ static int set_format(snd_usb_substream_t *subs, struct audioformat *fmt)
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 @@ static int parse_audio_endpoints(snd_usb_audio_t *chip, int iface_no)
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 */