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-rw-r--r--sound/usb/card.c771
1 files changed, 771 insertions, 0 deletions
diff --git a/sound/usb/card.c b/sound/usb/card.c
new file mode 100644
index 000000000..1fab97788
--- /dev/null
+++ b/sound/usb/card.c
@@ -0,0 +1,771 @@
+/*
+ * (Tentative) USB Audio Driver for ALSA
+ *
+ * Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
+ *
+ * Many codes borrowed from audio.c by
+ * Alan Cox (alan@lxorguk.ukuu.org.uk)
+ * Thomas Sailer (sailer@ife.ee.ethz.ch)
+ *
+ *
+ * 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
+ *
+ *
+ * NOTES:
+ *
+ * - the linked URBs would be preferred but not used so far because of
+ * the instability of unlinking.
+ * - type II is not supported properly. there is no device which supports
+ * this type *correctly*. SB extigy looks as if it supports, but it's
+ * indeed an AC3 stream packed in SPDIF frames (i.e. no real AC3 stream).
+ */
+
+
+#include <linux/bitops.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/usb.h>
+#include <linux/moduleparam.h>
+#include <linux/mutex.h>
+#include <linux/usb/audio.h>
+#include <linux/usb/audio-v2.h>
+#include <linux/module.h>
+
+#include <sound/control.h>
+#include <sound/core.h>
+#include <sound/info.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+
+#include "usbaudio.h"
+#include "card.h"
+#include "midi.h"
+#include "mixer.h"
+#include "proc.h"
+#include "quirks.h"
+#include "endpoint.h"
+#include "helper.h"
+#include "debug.h"
+#include "pcm.h"
+#include "format.h"
+#include "power.h"
+#include "stream.h"
+
+MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
+MODULE_DESCRIPTION("USB Audio");
+MODULE_LICENSE("GPL");
+MODULE_SUPPORTED_DEVICE("{{Generic,USB Audio}}");
+
+
+static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */
+static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */
+static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;/* Enable this card */
+/* Vendor/product IDs for this card */
+static int vid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
+static int pid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
+static int device_setup[SNDRV_CARDS]; /* device parameter for this card */
+static bool ignore_ctl_error;
+static bool autoclock = true;
+
+module_param_array(index, int, NULL, 0444);
+MODULE_PARM_DESC(index, "Index value for the USB audio adapter.");
+module_param_array(id, charp, NULL, 0444);
+MODULE_PARM_DESC(id, "ID string for the USB audio adapter.");
+module_param_array(enable, bool, NULL, 0444);
+MODULE_PARM_DESC(enable, "Enable USB audio adapter.");
+module_param_array(vid, int, NULL, 0444);
+MODULE_PARM_DESC(vid, "Vendor ID for the USB audio device.");
+module_param_array(pid, int, NULL, 0444);
+MODULE_PARM_DESC(pid, "Product ID for the USB audio device.");
+module_param_array(device_setup, int, NULL, 0444);
+MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
+module_param(ignore_ctl_error, bool, 0444);
+MODULE_PARM_DESC(ignore_ctl_error,
+ "Ignore errors from USB controller for mixer interfaces.");
+module_param(autoclock, bool, 0444);
+MODULE_PARM_DESC(autoclock, "Enable auto-clock selection for UAC2 devices (default: yes).");
+
+/*
+ * we keep the snd_usb_audio_t instances by ourselves for merging
+ * the all interfaces on the same card as one sound device.
+ */
+
+static DEFINE_MUTEX(register_mutex);
+static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
+static struct usb_driver usb_audio_driver;
+
+/*
+ * disconnect streams
+ * called from usb_audio_disconnect()
+ */
+static void snd_usb_stream_disconnect(struct snd_usb_stream *as)
+{
+ int idx;
+ struct snd_usb_substream *subs;
+
+ for (idx = 0; idx < 2; idx++) {
+ subs = &as->substream[idx];
+ if (!subs->num_formats)
+ continue;
+ subs->interface = -1;
+ subs->data_endpoint = NULL;
+ subs->sync_endpoint = NULL;
+ }
+}
+
+static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
+{
+ struct usb_device *dev = chip->dev;
+ struct usb_host_interface *alts;
+ struct usb_interface_descriptor *altsd;
+ struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
+
+ if (!iface) {
+ dev_err(&dev->dev, "%u:%d : does not exist\n",
+ ctrlif, interface);
+ return -EINVAL;
+ }
+
+ alts = &iface->altsetting[0];
+ altsd = get_iface_desc(alts);
+
+ /*
+ * Android with both accessory and audio interfaces enabled gets the
+ * interface numbers wrong.
+ */
+ if ((chip->usb_id == USB_ID(0x18d1, 0x2d04) ||
+ chip->usb_id == USB_ID(0x18d1, 0x2d05)) &&
+ interface == 0 &&
+ altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
+ altsd->bInterfaceSubClass == USB_SUBCLASS_VENDOR_SPEC) {
+ interface = 2;
+ iface = usb_ifnum_to_if(dev, interface);
+ if (!iface)
+ return -EINVAL;
+ alts = &iface->altsetting[0];
+ altsd = get_iface_desc(alts);
+ }
+
+ if (usb_interface_claimed(iface)) {
+ dev_dbg(&dev->dev, "%d:%d: skipping, already claimed\n",
+ ctrlif, interface);
+ return -EINVAL;
+ }
+
+ if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
+ altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
+ altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
+ int err = snd_usbmidi_create(chip->card, iface,
+ &chip->midi_list, NULL);
+ if (err < 0) {
+ dev_err(&dev->dev,
+ "%u:%d: cannot create sequencer device\n",
+ ctrlif, interface);
+ return -EINVAL;
+ }
+ usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
+
+ return 0;
+ }
+
+ if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
+ altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
+ altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
+ dev_dbg(&dev->dev,
+ "%u:%d: skipping non-supported interface %d\n",
+ ctrlif, interface, altsd->bInterfaceClass);
+ /* skip non-supported classes */
+ return -EINVAL;
+ }
+
+ if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
+ dev_err(&dev->dev, "low speed audio streaming not supported\n");
+ return -EINVAL;
+ }
+
+ if (! snd_usb_parse_audio_interface(chip, interface)) {
+ usb_set_interface(dev, interface, 0); /* reset the current interface */
+ usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * parse audio control descriptor and create pcm/midi streams
+ */
+static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
+{
+ struct usb_device *dev = chip->dev;
+ struct usb_host_interface *host_iface;
+ struct usb_interface_descriptor *altsd;
+ void *control_header;
+ int i, protocol;
+
+ /* find audiocontrol interface */
+ host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
+ control_header = snd_usb_find_csint_desc(host_iface->extra,
+ host_iface->extralen,
+ NULL, UAC_HEADER);
+ altsd = get_iface_desc(host_iface);
+ protocol = altsd->bInterfaceProtocol;
+
+ if (!control_header) {
+ dev_err(&dev->dev, "cannot find UAC_HEADER\n");
+ return -EINVAL;
+ }
+
+ switch (protocol) {
+ default:
+ dev_warn(&dev->dev,
+ "unknown interface protocol %#02x, assuming v1\n",
+ protocol);
+ /* fall through */
+
+ case UAC_VERSION_1: {
+ struct uac1_ac_header_descriptor *h1 = control_header;
+
+ if (!h1->bInCollection) {
+ dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
+ return -EINVAL;
+ }
+
+ if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
+ dev_err(&dev->dev, "invalid UAC_HEADER (v1)\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < h1->bInCollection; i++)
+ snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
+
+ break;
+ }
+
+ case UAC_VERSION_2: {
+ struct usb_interface_assoc_descriptor *assoc =
+ usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
+
+ if (!assoc) {
+ /*
+ * Firmware writers cannot count to three. So to find
+ * the IAD on the NuForce UDH-100, also check the next
+ * interface.
+ */
+ struct usb_interface *iface =
+ usb_ifnum_to_if(dev, ctrlif + 1);
+ if (iface &&
+ iface->intf_assoc &&
+ iface->intf_assoc->bFunctionClass == USB_CLASS_AUDIO &&
+ iface->intf_assoc->bFunctionProtocol == UAC_VERSION_2)
+ assoc = iface->intf_assoc;
+ }
+
+ if (!assoc) {
+ dev_err(&dev->dev, "Audio class v2 interfaces need an interface association\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < assoc->bInterfaceCount; i++) {
+ int intf = assoc->bFirstInterface + i;
+
+ if (intf != ctrlif)
+ snd_usb_create_stream(chip, ctrlif, intf);
+ }
+
+ break;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * free the chip instance
+ *
+ * here we have to do not much, since pcm and controls are already freed
+ *
+ */
+
+static int snd_usb_audio_free(struct snd_usb_audio *chip)
+{
+ struct snd_usb_endpoint *ep, *n;
+
+ list_for_each_entry_safe(ep, n, &chip->ep_list, list)
+ snd_usb_endpoint_free(ep);
+
+ mutex_destroy(&chip->mutex);
+ kfree(chip);
+ return 0;
+}
+
+static int snd_usb_audio_dev_free(struct snd_device *device)
+{
+ struct snd_usb_audio *chip = device->device_data;
+ return snd_usb_audio_free(chip);
+}
+
+/*
+ * create a chip instance and set its names.
+ */
+static int snd_usb_audio_create(struct usb_interface *intf,
+ struct usb_device *dev, int idx,
+ const struct snd_usb_audio_quirk *quirk,
+ struct snd_usb_audio **rchip)
+{
+ struct snd_card *card;
+ struct snd_usb_audio *chip;
+ int err, len;
+ char component[14];
+ static struct snd_device_ops ops = {
+ .dev_free = snd_usb_audio_dev_free,
+ };
+
+ *rchip = NULL;
+
+ switch (snd_usb_get_speed(dev)) {
+ case USB_SPEED_LOW:
+ case USB_SPEED_FULL:
+ case USB_SPEED_HIGH:
+ case USB_SPEED_WIRELESS:
+ case USB_SPEED_SUPER:
+ break;
+ default:
+ dev_err(&dev->dev, "unknown device speed %d\n", snd_usb_get_speed(dev));
+ return -ENXIO;
+ }
+
+ err = snd_card_new(&intf->dev, index[idx], id[idx], THIS_MODULE,
+ 0, &card);
+ if (err < 0) {
+ dev_err(&dev->dev, "cannot create card instance %d\n", idx);
+ return err;
+ }
+
+ chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+ if (! chip) {
+ snd_card_free(card);
+ return -ENOMEM;
+ }
+
+ mutex_init(&chip->mutex);
+ init_rwsem(&chip->shutdown_rwsem);
+ chip->index = idx;
+ chip->dev = dev;
+ chip->card = card;
+ chip->setup = device_setup[idx];
+ chip->autoclock = autoclock;
+ chip->probing = 1;
+
+ chip->usb_id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
+ le16_to_cpu(dev->descriptor.idProduct));
+ INIT_LIST_HEAD(&chip->pcm_list);
+ INIT_LIST_HEAD(&chip->ep_list);
+ INIT_LIST_HEAD(&chip->midi_list);
+ INIT_LIST_HEAD(&chip->mixer_list);
+
+ if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
+ snd_usb_audio_free(chip);
+ snd_card_free(card);
+ return err;
+ }
+
+ strcpy(card->driver, "USB-Audio");
+ sprintf(component, "USB%04x:%04x",
+ USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
+ snd_component_add(card, component);
+
+ /* retrieve the device string as shortname */
+ if (quirk && quirk->product_name && *quirk->product_name) {
+ strlcpy(card->shortname, quirk->product_name, sizeof(card->shortname));
+ } else {
+ if (!dev->descriptor.iProduct ||
+ usb_string(dev, dev->descriptor.iProduct,
+ card->shortname, sizeof(card->shortname)) <= 0) {
+ /* no name available from anywhere, so use ID */
+ sprintf(card->shortname, "USB Device %#04x:%#04x",
+ USB_ID_VENDOR(chip->usb_id),
+ USB_ID_PRODUCT(chip->usb_id));
+ }
+ }
+ strim(card->shortname);
+
+ /* retrieve the vendor and device strings as longname */
+ if (quirk && quirk->vendor_name && *quirk->vendor_name) {
+ len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
+ } else {
+ if (dev->descriptor.iManufacturer)
+ len = usb_string(dev, dev->descriptor.iManufacturer,
+ card->longname, sizeof(card->longname));
+ else
+ len = 0;
+ /* we don't really care if there isn't any vendor string */
+ }
+ if (len > 0) {
+ strim(card->longname);
+ if (*card->longname)
+ strlcat(card->longname, " ", sizeof(card->longname));
+ }
+
+ strlcat(card->longname, card->shortname, sizeof(card->longname));
+
+ len = strlcat(card->longname, " at ", sizeof(card->longname));
+
+ if (len < sizeof(card->longname))
+ usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
+
+ switch (snd_usb_get_speed(dev)) {
+ case USB_SPEED_LOW:
+ strlcat(card->longname, ", low speed", sizeof(card->longname));
+ break;
+ case USB_SPEED_FULL:
+ strlcat(card->longname, ", full speed", sizeof(card->longname));
+ break;
+ case USB_SPEED_HIGH:
+ strlcat(card->longname, ", high speed", sizeof(card->longname));
+ break;
+ case USB_SPEED_SUPER:
+ strlcat(card->longname, ", super speed", sizeof(card->longname));
+ break;
+ default:
+ break;
+ }
+
+ snd_usb_audio_create_proc(chip);
+
+ *rchip = chip;
+ return 0;
+}
+
+/*
+ * probe the active usb device
+ *
+ * note that this can be called multiple times per a device, when it
+ * includes multiple audio control interfaces.
+ *
+ * thus we check the usb device pointer and creates the card instance
+ * only at the first time. the successive calls of this function will
+ * append the pcm interface to the corresponding card.
+ */
+static int usb_audio_probe(struct usb_interface *intf,
+ const struct usb_device_id *usb_id)
+{
+ struct usb_device *dev = interface_to_usbdev(intf);
+ const struct snd_usb_audio_quirk *quirk =
+ (const struct snd_usb_audio_quirk *)usb_id->driver_info;
+ struct snd_usb_audio *chip;
+ int i, err;
+ struct usb_host_interface *alts;
+ int ifnum;
+ u32 id;
+
+ alts = &intf->altsetting[0];
+ ifnum = get_iface_desc(alts)->bInterfaceNumber;
+ id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
+ le16_to_cpu(dev->descriptor.idProduct));
+ if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
+ return -ENXIO;
+
+ err = snd_usb_apply_boot_quirk(dev, intf, quirk);
+ if (err < 0)
+ return err;
+
+ /*
+ * found a config. now register to ALSA
+ */
+
+ /* check whether it's already registered */
+ chip = NULL;
+ mutex_lock(&register_mutex);
+ for (i = 0; i < SNDRV_CARDS; i++) {
+ if (usb_chip[i] && usb_chip[i]->dev == dev) {
+ if (usb_chip[i]->shutdown) {
+ dev_err(&dev->dev, "USB device is in the shutdown state, cannot create a card instance\n");
+ err = -EIO;
+ goto __error;
+ }
+ chip = usb_chip[i];
+ chip->probing = 1;
+ break;
+ }
+ }
+ if (! chip) {
+ /* it's a fresh one.
+ * now look for an empty slot and create a new card instance
+ */
+ for (i = 0; i < SNDRV_CARDS; i++)
+ if (enable[i] && ! usb_chip[i] &&
+ (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
+ (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
+ err = snd_usb_audio_create(intf, dev, i, quirk,
+ &chip);
+ if (err < 0)
+ goto __error;
+ chip->pm_intf = intf;
+ break;
+ }
+ if (!chip) {
+ dev_err(&dev->dev, "no available usb audio device\n");
+ err = -ENODEV;
+ goto __error;
+ }
+ }
+
+ /*
+ * For devices with more than one control interface, we assume the
+ * first contains the audio controls. We might need a more specific
+ * check here in the future.
+ */
+ if (!chip->ctrl_intf)
+ chip->ctrl_intf = alts;
+
+ chip->txfr_quirk = 0;
+ err = 1; /* continue */
+ if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
+ /* need some special handlings */
+ err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk);
+ if (err < 0)
+ goto __error;
+ }
+
+ if (err > 0) {
+ /* create normal USB audio interfaces */
+ err = snd_usb_create_streams(chip, ifnum);
+ if (err < 0)
+ goto __error;
+ err = snd_usb_create_mixer(chip, ifnum, ignore_ctl_error);
+ if (err < 0)
+ goto __error;
+ }
+
+ /* we are allowed to call snd_card_register() many times */
+ err = snd_card_register(chip->card);
+ if (err < 0)
+ goto __error;
+
+ usb_chip[chip->index] = chip;
+ chip->num_interfaces++;
+ chip->probing = 0;
+ usb_set_intfdata(intf, chip);
+ mutex_unlock(&register_mutex);
+ return 0;
+
+ __error:
+ if (chip) {
+ if (!chip->num_interfaces)
+ snd_card_free(chip->card);
+ chip->probing = 0;
+ }
+ mutex_unlock(&register_mutex);
+ return err;
+}
+
+/*
+ * we need to take care of counter, since disconnection can be called also
+ * many times as well as usb_audio_probe().
+ */
+static void usb_audio_disconnect(struct usb_interface *intf)
+{
+ struct snd_usb_audio *chip = usb_get_intfdata(intf);
+ struct snd_card *card;
+ struct list_head *p;
+ bool was_shutdown;
+
+ if (chip == (void *)-1L)
+ return;
+
+ card = chip->card;
+ down_write(&chip->shutdown_rwsem);
+ was_shutdown = chip->shutdown;
+ chip->shutdown = 1;
+ up_write(&chip->shutdown_rwsem);
+
+ mutex_lock(&register_mutex);
+ if (!was_shutdown) {
+ struct snd_usb_stream *as;
+ struct snd_usb_endpoint *ep;
+ struct usb_mixer_interface *mixer;
+
+ snd_card_disconnect(card);
+ /* release the pcm resources */
+ list_for_each_entry(as, &chip->pcm_list, list) {
+ snd_usb_stream_disconnect(as);
+ }
+ /* release the endpoint resources */
+ list_for_each_entry(ep, &chip->ep_list, list) {
+ snd_usb_endpoint_release(ep);
+ }
+ /* release the midi resources */
+ list_for_each(p, &chip->midi_list) {
+ snd_usbmidi_disconnect(p);
+ }
+ /* release mixer resources */
+ list_for_each_entry(mixer, &chip->mixer_list, list) {
+ snd_usb_mixer_disconnect(mixer);
+ }
+ }
+
+ chip->num_interfaces--;
+ if (chip->num_interfaces <= 0) {
+ usb_chip[chip->index] = NULL;
+ mutex_unlock(&register_mutex);
+ snd_card_free_when_closed(card);
+ } else {
+ mutex_unlock(&register_mutex);
+ }
+}
+
+#ifdef CONFIG_PM
+
+int snd_usb_autoresume(struct snd_usb_audio *chip)
+{
+ int err = -ENODEV;
+
+ down_read(&chip->shutdown_rwsem);
+ if (chip->probing && chip->in_pm)
+ err = 0;
+ else if (!chip->shutdown)
+ err = usb_autopm_get_interface(chip->pm_intf);
+ up_read(&chip->shutdown_rwsem);
+
+ return err;
+}
+
+void snd_usb_autosuspend(struct snd_usb_audio *chip)
+{
+ down_read(&chip->shutdown_rwsem);
+ if (!chip->shutdown && !chip->probing && !chip->in_pm)
+ usb_autopm_put_interface(chip->pm_intf);
+ up_read(&chip->shutdown_rwsem);
+}
+
+static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
+{
+ struct snd_usb_audio *chip = usb_get_intfdata(intf);
+ struct snd_usb_stream *as;
+ struct usb_mixer_interface *mixer;
+ struct list_head *p;
+
+ if (chip == (void *)-1L)
+ return 0;
+
+ if (!PMSG_IS_AUTO(message)) {
+ snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
+ if (!chip->num_suspended_intf++) {
+ list_for_each_entry(as, &chip->pcm_list, list) {
+ snd_pcm_suspend_all(as->pcm);
+ as->substream[0].need_setup_ep =
+ as->substream[1].need_setup_ep = true;
+ }
+ list_for_each(p, &chip->midi_list) {
+ snd_usbmidi_suspend(p);
+ }
+ }
+ } else {
+ /*
+ * otherwise we keep the rest of the system in the dark
+ * to keep this transparent
+ */
+ if (!chip->num_suspended_intf++)
+ chip->autosuspended = 1;
+ }
+
+ if (chip->num_suspended_intf == 1)
+ list_for_each_entry(mixer, &chip->mixer_list, list)
+ snd_usb_mixer_suspend(mixer);
+
+ return 0;
+}
+
+static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
+{
+ struct snd_usb_audio *chip = usb_get_intfdata(intf);
+ struct usb_mixer_interface *mixer;
+ struct list_head *p;
+ int err = 0;
+
+ if (chip == (void *)-1L)
+ return 0;
+ if (--chip->num_suspended_intf)
+ return 0;
+
+ chip->in_pm = 1;
+ /*
+ * ALSA leaves material resumption to user space
+ * we just notify and restart the mixers
+ */
+ list_for_each_entry(mixer, &chip->mixer_list, list) {
+ err = snd_usb_mixer_resume(mixer, reset_resume);
+ if (err < 0)
+ goto err_out;
+ }
+
+ list_for_each(p, &chip->midi_list) {
+ snd_usbmidi_resume(p);
+ }
+
+ if (!chip->autosuspended)
+ snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
+ chip->autosuspended = 0;
+
+err_out:
+ chip->in_pm = 0;
+ return err;
+}
+
+static int usb_audio_resume(struct usb_interface *intf)
+{
+ return __usb_audio_resume(intf, false);
+}
+
+static int usb_audio_reset_resume(struct usb_interface *intf)
+{
+ return __usb_audio_resume(intf, true);
+}
+#else
+#define usb_audio_suspend NULL
+#define usb_audio_resume NULL
+#define usb_audio_reset_resume NULL
+#endif /* CONFIG_PM */
+
+static struct usb_device_id usb_audio_ids [] = {
+#include "quirks-table.h"
+ { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
+ .bInterfaceClass = USB_CLASS_AUDIO,
+ .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
+ { } /* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, usb_audio_ids);
+
+/*
+ * entry point for linux usb interface
+ */
+
+static struct usb_driver usb_audio_driver = {
+ .name = "snd-usb-audio",
+ .probe = usb_audio_probe,
+ .disconnect = usb_audio_disconnect,
+ .suspend = usb_audio_suspend,
+ .resume = usb_audio_resume,
+ .reset_resume = usb_audio_reset_resume,
+ .id_table = usb_audio_ids,
+ .supports_autosuspend = 1,
+};
+
+module_usb_driver(usb_audio_driver);