linux-stable/sound/usb/card.c
Gustavo A. R. Silva c0dbbdad4e ALSA: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200708203236.GA5112@embeddedor
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-07-09 13:01:29 +02:00

977 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* (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)
*
* Audio Class 3.0 support by Ruslan Bilovol <ruslan.bilovol@gmail.com>
*
* 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/usb/audio-v3.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"
#include "media.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;
static char *quirk_alias[SNDRV_CARDS];
static char *delayed_register[SNDRV_CARDS];
bool snd_usb_use_vmalloc = true;
bool snd_usb_skip_validation;
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).");
module_param_array(quirk_alias, charp, NULL, 0444);
MODULE_PARM_DESC(quirk_alias, "Quirk aliases, e.g. 0123abcd:5678beef.");
module_param_array(delayed_register, charp, NULL, 0444);
MODULE_PARM_DESC(delayed_register, "Quirk for delayed registration, given by id:iface, e.g. 0123abcd:4.");
module_param_named(use_vmalloc, snd_usb_use_vmalloc, bool, 0444);
MODULE_PARM_DESC(use_vmalloc, "Use vmalloc for PCM intermediate buffers (default: yes).");
module_param_named(skip_validation, snd_usb_skip_validation, bool, 0444);
MODULE_PARM_DESC(skip_validation, "Skip unit descriptor validation (default: no).");
/*
* 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,
chip->usb_id);
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 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;
int i, protocol;
/* find audiocontrol interface */
host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
altsd = get_iface_desc(host_iface);
protocol = altsd->bInterfaceProtocol;
switch (protocol) {
default:
dev_warn(&dev->dev,
"unknown interface protocol %#02x, assuming v1\n",
protocol);
fallthrough;
case UAC_VERSION_1: {
struct uac1_ac_header_descriptor *h1;
int rest_bytes;
h1 = snd_usb_find_csint_desc(host_iface->extra,
host_iface->extralen,
NULL, UAC_HEADER);
if (!h1 || h1->bLength < sizeof(*h1)) {
dev_err(&dev->dev, "cannot find UAC_HEADER\n");
return -EINVAL;
}
rest_bytes = (void *)(host_iface->extra +
host_iface->extralen) - (void *)h1;
/* just to be sure -- this shouldn't hit at all */
if (rest_bytes <= 0) {
dev_err(&dev->dev, "invalid control header\n");
return -EINVAL;
}
if (rest_bytes < sizeof(*h1)) {
dev_err(&dev->dev, "too short v1 buffer descriptor\n");
return -EINVAL;
}
if (!h1->bInCollection) {
dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
return -EINVAL;
}
if (rest_bytes < h1->bLength) {
dev_err(&dev->dev, "invalid buffer length (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:
case UAC_VERSION_3: {
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/v3 interfaces need an interface association\n");
return -EINVAL;
}
if (protocol == UAC_VERSION_3) {
int badd = assoc->bFunctionSubClass;
if (badd != UAC3_FUNCTION_SUBCLASS_FULL_ADC_3_0 &&
(badd < UAC3_FUNCTION_SUBCLASS_GENERIC_IO ||
badd > UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE)) {
dev_err(&dev->dev,
"Unsupported UAC3 BADD profile\n");
return -EINVAL;
}
chip->badd_profile = badd;
}
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 void snd_usb_audio_free(struct snd_card *card)
{
struct snd_usb_audio *chip = card->private_data;
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);
if (!atomic_read(&chip->shutdown))
dev_set_drvdata(&chip->dev->dev, NULL);
}
static void usb_audio_make_shortname(struct usb_device *dev,
struct snd_usb_audio *chip,
const struct snd_usb_audio_quirk *quirk)
{
struct snd_card *card = chip->card;
if (quirk && quirk->product_name && *quirk->product_name) {
strlcpy(card->shortname, quirk->product_name,
sizeof(card->shortname));
return;
}
/* retrieve the device string as shortname */
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);
}
static void usb_audio_make_longname(struct usb_device *dev,
struct snd_usb_audio *chip,
const struct snd_usb_audio_quirk *quirk)
{
struct snd_card *card = chip->card;
int len;
/* shortcut - if any pre-defined string is given, use it */
if (quirk && quirk->profile_name && *quirk->profile_name) {
strlcpy(card->longname, quirk->profile_name,
sizeof(card->longname));
return;
}
if (quirk && quirk->vendor_name && *quirk->vendor_name) {
len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
} else {
/* retrieve the vendor and device strings as longname */
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;
case USB_SPEED_SUPER_PLUS:
strlcat(card->longname, ", super speed plus", sizeof(card->longname));
break;
default:
break;
}
}
/*
* 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,
unsigned int usb_id,
struct snd_usb_audio **rchip)
{
struct snd_card *card;
struct snd_usb_audio *chip;
int err;
char component[14];
*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:
case USB_SPEED_SUPER_PLUS:
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,
sizeof(*chip), &card);
if (err < 0) {
dev_err(&dev->dev, "cannot create card instance %d\n", idx);
return err;
}
chip = card->private_data;
mutex_init(&chip->mutex);
init_waitqueue_head(&chip->shutdown_wait);
chip->index = idx;
chip->dev = dev;
chip->card = card;
chip->setup = device_setup[idx];
chip->autoclock = autoclock;
atomic_set(&chip->active, 1); /* avoid autopm during probing */
atomic_set(&chip->usage_count, 0);
atomic_set(&chip->shutdown, 0);
chip->usb_id = usb_id;
INIT_LIST_HEAD(&chip->pcm_list);
INIT_LIST_HEAD(&chip->ep_list);
INIT_LIST_HEAD(&chip->midi_list);
INIT_LIST_HEAD(&chip->mixer_list);
card->private_free = snd_usb_audio_free;
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);
usb_audio_make_shortname(dev, chip, quirk);
usb_audio_make_longname(dev, chip, quirk);
snd_usb_audio_create_proc(chip);
*rchip = chip;
return 0;
}
/* look for a matching quirk alias id */
static bool get_alias_id(struct usb_device *dev, unsigned int *id)
{
int i;
unsigned int src, dst;
for (i = 0; i < ARRAY_SIZE(quirk_alias); i++) {
if (!quirk_alias[i] ||
sscanf(quirk_alias[i], "%x:%x", &src, &dst) != 2 ||
src != *id)
continue;
dev_info(&dev->dev,
"device (%04x:%04x): applying quirk alias %04x:%04x\n",
USB_ID_VENDOR(*id), USB_ID_PRODUCT(*id),
USB_ID_VENDOR(dst), USB_ID_PRODUCT(dst));
*id = dst;
return true;
}
return false;
}
static bool check_delayed_register_option(struct snd_usb_audio *chip, int iface)
{
int i;
unsigned int id, inum;
for (i = 0; i < ARRAY_SIZE(delayed_register); i++) {
if (delayed_register[i] &&
sscanf(delayed_register[i], "%x:%x", &id, &inum) == 2 &&
id == chip->usb_id)
return inum != iface;
}
return false;
}
static const struct usb_device_id usb_audio_ids[]; /* defined below */
/* look for the corresponding quirk */
static const struct snd_usb_audio_quirk *
get_alias_quirk(struct usb_device *dev, unsigned int id)
{
const struct usb_device_id *p;
for (p = usb_audio_ids; p->match_flags; p++) {
/* FIXME: this checks only vendor:product pair in the list */
if ((p->match_flags & USB_DEVICE_ID_MATCH_DEVICE) ==
USB_DEVICE_ID_MATCH_DEVICE &&
p->idVendor == USB_ID_VENDOR(id) &&
p->idProduct == USB_ID_PRODUCT(id))
return (const struct snd_usb_audio_quirk *)p->driver_info;
}
return NULL;
}
/*
* 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 (get_alias_id(dev, &id))
quirk = get_alias_quirk(dev, id);
if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
return -ENXIO;
err = snd_usb_apply_boot_quirk(dev, intf, quirk, id);
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 (atomic_read(&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];
atomic_inc(&chip->active); /* avoid autopm */
break;
}
}
if (! chip) {
err = snd_usb_apply_boot_quirk_once(dev, intf, quirk, id);
if (err < 0)
goto __error;
/* 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 (!usb_chip[i] &&
(vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
(pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
if (enable[i]) {
err = snd_usb_audio_create(intf, dev, i, quirk,
id, &chip);
if (err < 0)
goto __error;
break;
} else if (vid[i] != -1 || pid[i] != -1) {
dev_info(&dev->dev,
"device (%04x:%04x) is disabled\n",
USB_ID_VENDOR(id),
USB_ID_PRODUCT(id));
err = -ENOENT;
goto __error;
}
}
if (!chip) {
dev_err(&dev->dev, "no available usb audio device\n");
err = -ENODEV;
goto __error;
}
}
if (chip->num_interfaces >= MAX_CARD_INTERFACES) {
dev_info(&dev->dev, "Too many interfaces assigned to the single USB-audio card\n");
err = -EINVAL;
goto __error;
}
dev_set_drvdata(&dev->dev, chip);
/*
* 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;
}
if (chip->need_delayed_register) {
dev_info(&dev->dev,
"Found post-registration device assignment: %08x:%02x\n",
chip->usb_id, ifnum);
chip->need_delayed_register = false; /* clear again */
}
/* we are allowed to call snd_card_register() many times, but first
* check to see if a device needs to skip it or do anything special
*/
if (!snd_usb_registration_quirk(chip, ifnum) &&
!check_delayed_register_option(chip, ifnum)) {
err = snd_card_register(chip->card);
if (err < 0)
goto __error;
}
if (quirk && quirk->shares_media_device) {
/* don't want to fail when snd_media_device_create() fails */
snd_media_device_create(chip, intf);
}
usb_chip[chip->index] = chip;
chip->intf[chip->num_interfaces] = intf;
chip->num_interfaces++;
usb_set_intfdata(intf, chip);
atomic_dec(&chip->active);
mutex_unlock(&register_mutex);
return 0;
__error:
if (chip) {
/* chip->active is inside the chip->card object,
* decrement before memory is possibly returned.
*/
atomic_dec(&chip->active);
if (!chip->num_interfaces)
snd_card_free(chip->card);
}
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;
if (chip == (void *)-1L)
return;
card = chip->card;
mutex_lock(&register_mutex);
if (atomic_inc_return(&chip->shutdown) == 1) {
struct snd_usb_stream *as;
struct snd_usb_endpoint *ep;
struct usb_mixer_interface *mixer;
/* wait until all pending tasks done;
* they are protected by snd_usb_lock_shutdown()
*/
wait_event(chip->shutdown_wait,
!atomic_read(&chip->usage_count));
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);
}
/*
* Nice to check quirk && quirk->shares_media_device and
* then call the snd_media_device_delete(). Don't have
* access to the quirk here. snd_media_device_delete()
* accesses mixer_list
*/
snd_media_device_delete(chip);
/* 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);
}
}
/* lock the shutdown (disconnect) task and autoresume */
int snd_usb_lock_shutdown(struct snd_usb_audio *chip)
{
int err;
atomic_inc(&chip->usage_count);
if (atomic_read(&chip->shutdown)) {
err = -EIO;
goto error;
}
err = snd_usb_autoresume(chip);
if (err < 0)
goto error;
return 0;
error:
if (atomic_dec_and_test(&chip->usage_count))
wake_up(&chip->shutdown_wait);
return err;
}
/* autosuspend and unlock the shutdown */
void snd_usb_unlock_shutdown(struct snd_usb_audio *chip)
{
snd_usb_autosuspend(chip);
if (atomic_dec_and_test(&chip->usage_count))
wake_up(&chip->shutdown_wait);
}
#ifdef CONFIG_PM
int snd_usb_autoresume(struct snd_usb_audio *chip)
{
int i, err;
if (atomic_read(&chip->shutdown))
return -EIO;
if (atomic_inc_return(&chip->active) != 1)
return 0;
for (i = 0; i < chip->num_interfaces; i++) {
err = usb_autopm_get_interface(chip->intf[i]);
if (err < 0) {
/* rollback */
while (--i >= 0)
usb_autopm_put_interface(chip->intf[i]);
atomic_dec(&chip->active);
return err;
}
}
return 0;
}
void snd_usb_autosuspend(struct snd_usb_audio *chip)
{
int i;
if (atomic_read(&chip->shutdown))
return;
if (!atomic_dec_and_test(&chip->active))
return;
for (i = 0; i < chip->num_interfaces; i++)
usb_autopm_put_interface(chip->intf[i]);
}
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 (!chip->num_suspended_intf++) {
list_for_each_entry(as, &chip->pcm_list, list) {
snd_usb_pcm_suspend(as);
as->substream[0].need_setup_ep =
as->substream[1].need_setup_ep = true;
}
list_for_each(p, &chip->midi_list)
snd_usbmidi_suspend(p);
list_for_each_entry(mixer, &chip->mixer_list, list)
snd_usb_mixer_suspend(mixer);
}
if (!PMSG_IS_AUTO(message) && !chip->system_suspend) {
snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
chip->system_suspend = chip->num_suspended_intf;
}
return 0;
}
static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
{
struct snd_usb_audio *chip = usb_get_intfdata(intf);
struct snd_usb_stream *as;
struct usb_mixer_interface *mixer;
struct list_head *p;
int err = 0;
if (chip == (void *)-1L)
return 0;
atomic_inc(&chip->active); /* avoid autopm */
if (chip->num_suspended_intf > 1)
goto out;
list_for_each_entry(as, &chip->pcm_list, list) {
err = snd_usb_pcm_resume(as);
if (err < 0)
goto err_out;
}
/*
* 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);
}
out:
if (chip->num_suspended_intf == chip->system_suspend) {
snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
chip->system_suspend = 0;
}
chip->num_suspended_intf--;
err_out:
atomic_dec(&chip->active); /* allow autopm after this point */
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 const 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);