Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 573567e0 authored by Clemens Ladisch's avatar Clemens Ladisch Committed by Jaroslav Kysela
Browse files

[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: default avatarClemens Ladisch <clemens@ladisch.de>
parent b0af0de5

sound/usb/usbaudio.c

+25 −12
Original line number Diff line number Diff line
@@ -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 */