path: root/sound/usb/stream.c

/*
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */


#include <linux/init.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>

#include <sound/core.h>
#include <sound/pcm.h>

#include "usbaudio.h"
#include "card.h"
#include "proc.h"
#include "quirks.h"
#include "endpoint.h"
#include "pcm.h"
#include "helper.h"
#include "format.h"
#include "clock.h"
#include "stream.h"

/*
 * free a substream
 */
static void free_substream(struct snd_usb_substream *subs)
{
	struct list_head *p, *n;

	if (!subs->num_formats)
		return; /* not initialized */
	list_for_each_safe(p, n, &subs->fmt_list) {
		struct audioformat *fp = list_entry(p, struct audioformat, list);
		kfree(fp->rate_table);
		kfree(fp);
	}
	kfree(subs->rate_list.list);
}


/*
 * free a usb stream instance
 */
static void snd_usb_audio_stream_free(struct snd_usb_stream *stream)
{
	free_substream(&stream->substream[0]);
	free_substream(&stream->substream[1]);
	list_del(&stream->list);
	kfree(stream);
}

static void snd_usb_audio_pcm_free(struct snd_pcm *pcm)
{
	struct snd_usb_stream *stream = pcm->private_data;
	if (stream) {
		stream->pcm = NULL;
		snd_usb_audio_stream_free(stream);
	}
}

/*
 * initialize the substream instance.
 */

static void snd_usb_init_substream(struct snd_usb_stream *as,
				   int stream,
				   struct audioformat *fp)
{
	struct snd_usb_substream *subs = &as->substream[stream];

	INIT_LIST_HEAD(&subs->fmt_list);
	spin_lock_init(&subs->lock);

	subs->stream = as;
	subs->direction = stream;
	subs->dev = as->chip->dev;
	subs->txfr_quirk = as->chip->txfr_quirk;
	subs->speed = snd_usb_get_speed(subs->dev);

	snd_usb_set_pcm_ops(as->pcm, stream);

	list_add_tail(&fp->list, &subs->fmt_list);
	subs->formats |= fp->formats;
	subs->num_formats++;
	subs->fmt_type = fp->fmt_type;
	subs->ep_num = fp->endpoint;
}

/*
 * add this endpoint to the chip instance.
 * if a stream with the same endpoint already exists, append to it.
 * if not, create a new pcm stream.
 */
int snd_usb_add_audio_stream(struct snd_usb_audio *chip,
			     int stream,
			     struct audioformat *fp)
{
	struct list_head *p;
	struct snd_usb_stream *as;
	struct snd_usb_substream *subs;
	struct snd_pcm *pcm;
	int err;

	list_for_each(p, &chip->pcm_list) {
		as = list_entry(p, struct snd_usb_stream, list);
		if (as->fmt_type != fp->fmt_type)
			continue;
		subs = &as->substream[stream];
		if (subs->ep_num == fp->endpoint) {
			list_add_tail(&fp->list, &subs->fmt_list);
			subs->num_formats++;
			subs->formats |= fp->formats;
			return 0;
		}
	}
	/* look for an empty stream */
	list_for_each(p, &chip->pcm_list) {
		as = list_entry(p, struct snd_usb_stream, list);
		if (as->fmt_type != fp->fmt_type)
			continue;
		subs = &as->substream[stream];
		if (subs->ep_num)
			continue;
		err = snd_pcm_new_stream(as->pcm, stream, 1);
		if (err < 0)
			return err;
		snd_usb_init_substream(as, stream, fp);
		return 0;
	}

	/* create a new pcm */
	as = kzalloc(sizeof(*as), GFP_KERNEL);
	if (!as)
		return -ENOMEM;
	as->pcm_index = chip->pcm_devs;
	as->chip = chip;
	as->fmt_type = fp->fmt_type;
	err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
			  &pcm);
	if (err < 0) {
		kfree(as);
		return err;
	}
	as->pcm = pcm;
	pcm->private_data = as;
	pcm->private_free = snd_usb_audio_pcm_free;
	pcm->info_flags = 0;
	if (chip->pcm_devs > 0)
		sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
	else
		strcpy(pcm->name, "USB Audio");

	snd_usb_init_substream(as, stream, fp);

	list_add(&as->list, &chip->pcm_list);
	chip->pcm_devs++;

	snd_usb_proc_pcm_format_add(as);

	return 0;
}

static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
					 struct usb_host_interface *alts,
					 int protocol, int iface_no)
{
	/* parsed with a v1 header here. that's ok as we only look at the
	 * header first which is the same for both versions */
	struct uac_iso_endpoint_descriptor *csep;
	struct usb_interface_descriptor *altsd = get_iface_desc(alts);
	int attributes = 0;

	csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);

	/* Creamware Noah has this descriptor after the 2nd endpoint */
	if (!csep && altsd->bNumEndpoints >= 2)
		csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);

	if (!csep || csep->bLength < 7 ||
	    csep->bDescriptorSubtype != UAC_EP_GENERAL) {
		snd_printk(KERN_WARNING "%d:%u:%d : no or invalid"
			   " class specific endpoint descriptor\n",
			   chip->dev->devnum, iface_no,
			   altsd->bAlternateSetting);
		return 0;
	}

	if (protocol == UAC_VERSION_1) {
		attributes = csep->bmAttributes;
	} else {
		struct uac2_iso_endpoint_descriptor *csep2 =
			(struct uac2_iso_endpoint_descriptor *) csep;

		attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;

		/* emulate the endpoint attributes of a v1 device */
		if (csep2->bmControls & UAC2_CONTROL_PITCH)
			attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
	}

	return attributes;
}

static struct uac2_input_terminal_descriptor *
	snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
					       int terminal_id)
{
	struct uac2_input_terminal_descriptor *term = NULL;

	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
					       ctrl_iface->extralen,
					       term, UAC_INPUT_TERMINAL))) {
		if (term->bTerminalID == terminal_id)
			return term;
	}

	return NULL;
}

static struct uac2_output_terminal_descriptor *
	snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
						int terminal_id)
{
	struct uac2_output_terminal_descriptor *term = NULL;

	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
					       ctrl_iface->extralen,
					       term, UAC_OUTPUT_TERMINAL)))