summaryrefslogtreecommitdiffstats
path: root/kernel/sound/usb/card.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/sound/usb/card.c')
-rw-r--r--kernel/sound/usb/card.c110
1 files changed, 63 insertions, 47 deletions
diff --git a/kernel/sound/usb/card.c b/kernel/sound/usb/card.c
index 045059398..1f09d9591 100644
--- a/kernel/sound/usb/card.c
+++ b/kernel/sound/usb/card.c
@@ -365,13 +365,15 @@ static int snd_usb_audio_create(struct usb_interface *intf,
}
mutex_init(&chip->mutex);
- init_rwsem(&chip->shutdown_rwsem);
+ init_waitqueue_head(&chip->shutdown_wait);
chip->index = idx;
chip->dev = dev;
chip->card = card;
chip->setup = device_setup[idx];
chip->autoclock = autoclock;
- chip->probing = 1;
+ 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(le16_to_cpu(dev->descriptor.idVendor),
le16_to_cpu(dev->descriptor.idProduct));
@@ -495,13 +497,13 @@ static int usb_audio_probe(struct usb_interface *intf,
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) {
+ 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];
- chip->probing = 1;
+ atomic_inc(&chip->active); /* avoid autopm */
break;
}
}
@@ -561,8 +563,8 @@ static int usb_audio_probe(struct usb_interface *intf,
usb_chip[chip->index] = chip;
chip->num_interfaces++;
- chip->probing = 0;
usb_set_intfdata(intf, chip);
+ atomic_dec(&chip->active);
mutex_unlock(&register_mutex);
return 0;
@@ -570,7 +572,7 @@ static int usb_audio_probe(struct usb_interface *intf,
if (chip) {
if (!chip->num_interfaces)
snd_card_free(chip->card);
- chip->probing = 0;
+ atomic_dec(&chip->active);
}
mutex_unlock(&register_mutex);
return err;
@@ -585,23 +587,23 @@ 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) {
+ 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) {
@@ -631,28 +633,52 @@ static void usb_audio_disconnect(struct usb_interface *intf)
}
}
-#ifdef CONFIG_PM
-
-int snd_usb_autoresume(struct snd_usb_audio *chip)
+/* lock the shutdown (disconnect) task and autoresume */
+int snd_usb_lock_shutdown(struct snd_usb_audio *chip)
{
- int err = -ENODEV;
+ int err;
- 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);
+ 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)
+{
+ if (atomic_read(&chip->shutdown))
+ return -EIO;
+ if (atomic_inc_return(&chip->active) == 1)
+ return usb_autopm_get_interface(chip->pm_intf);
+ return 0;
+}
+
void snd_usb_autosuspend(struct snd_usb_audio *chip)
{
- down_read(&chip->shutdown_rwsem);
- if (!chip->shutdown && !chip->probing && !chip->in_pm)
+ if (atomic_read(&chip->shutdown))
+ return;
+ if (atomic_dec_and_test(&chip->active))
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)
@@ -665,30 +691,20 @@ static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
if (chip == (void *)-1L)
return 0;
- if (!PMSG_IS_AUTO(message)) {
+ chip->autosuspended = !!PMSG_IS_AUTO(message);
+ if (!chip->autosuspended)
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);
- }
+ 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;
}
- } 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(p, &chip->midi_list)
+ snd_usbmidi_suspend(p);
list_for_each_entry(mixer, &chip->mixer_list, list)
snd_usb_mixer_suspend(mixer);
+ }
return 0;
}
@@ -705,7 +721,7 @@ static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
if (--chip->num_suspended_intf)
return 0;
- chip->in_pm = 1;
+ atomic_inc(&chip->active); /* avoid autopm */
/*
* ALSA leaves material resumption to user space
* we just notify and restart the mixers
@@ -725,7 +741,7 @@ static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
chip->autosuspended = 0;
err_out:
- chip->in_pm = 0;
+ atomic_dec(&chip->active); /* allow autopm after this point */
return err;
}