10 files changed, 159 insertions, 56 deletions

diff --git a/sound/usb/card.c b/sound/usb/card.c
index 561bb74fd364..dbf7999d18b4 100644
--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -339,7 +339,7 @@ static int snd_usb_audio_create(struct usb_device *dev, int idx,
         }
 
         mutex_init(&chip->mutex);
-        mutex_init(&chip->shutdown_mutex);
+        init_rwsem(&chip->shutdown_rwsem);
         chip->index = idx;
         chip->dev = dev;
         chip->card = card;
@@ -559,9 +559,11 @@ static void snd_usb_audio_disconnect(struct usb_device *dev,
                 return;
 
         card = chip->card;
-        mutex_lock(&register_mutex);
-        mutex_lock(&chip->shutdown_mutex);
+        down_write(&chip->shutdown_rwsem);
         chip->shutdown = 1;
+        up_write(&chip->shutdown_rwsem);
+
+        mutex_lock(&register_mutex);
         chip->num_interfaces--;
         if (chip->num_interfaces <= 0) {
                 snd_card_disconnect(card);
@@ -582,11 +584,9 @@ static void snd_usb_audio_disconnect(struct usb_device *dev,
                         snd_usb_mixer_disconnect(p);
                 }
                 usb_chip[chip->index] = NULL;
-                mutex_unlock(&chip->shutdown_mutex);
                 mutex_unlock(&register_mutex);
                 snd_card_free_when_closed(card);
         } else {
-                mutex_unlock(&chip->shutdown_mutex);
                 mutex_unlock(&register_mutex);
         }
 }
@@ -618,16 +618,20 @@ int snd_usb_autoresume(struct snd_usb_audio *chip)
 {
         int err = -ENODEV;
 
+        down_read(&chip->shutdown_rwsem);
         if (!chip->shutdown && !chip->probing)
                 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)
                 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)
diff --git a/sound/usb/card.h b/sound/usb/card.h
index afa4f9e9b27a..814cb357ff88 100644
--- a/sound/usb/card.h
+++ b/sound/usb/card.h
@@ -126,6 +126,7 @@ struct snd_usb_substream {
         struct snd_usb_endpoint *sync_endpoint;
         unsigned long flags;
         bool need_setup_ep;             /* (re)configure EP at prepare? */
+        unsigned int speed;             /* USB_SPEED_XXX */
 
         u64 formats;                    /* format bitmasks (all or'ed) */
         unsigned int num_formats;               /* number of supported audio formats (list) */
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index 7f78c6d782b0..34de6f2faf61 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -35,6 +35,7 @@
 
 #define EP_FLAG_ACTIVATED       0
 #define EP_FLAG_RUNNING         1
+#define EP_FLAG_STOPPING        2
 
 /*
  * snd_usb_endpoint is a model that abstracts everything related to an
@@ -502,10 +503,20 @@ static int wait_clear_urbs(struct snd_usb_endpoint *ep)
         if (alive)
                 snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n",
                                         alive, ep->ep_num);
+        clear_bit(EP_FLAG_STOPPING, &ep->flags);
 
         return 0;
 }
 
+/* sync the pending stop operation;
+ * this function itself doesn't trigger the stop operation
+ */
+void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
+{
+        if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
+                wait_clear_urbs(ep);
+}
+
 /*
  * unlink active urbs.
  */
@@ -918,6 +929,8 @@ void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep,
 
                 if (wait)
                         wait_clear_urbs(ep);
+                else
+                        set_bit(EP_FLAG_STOPPING, &ep->flags);
         }
 }
 
diff --git a/sound/usb/endpoint.h b/sound/usb/endpoint.h
index 6376ccf10fd4..3d4c9705041f 100644
--- a/sound/usb/endpoint.h
+++ b/sound/usb/endpoint.h
@@ -19,6 +19,7 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
 int  snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep);
 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep,
                            int force, int can_sleep, int wait);
+void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep);
 int  snd_usb_endpoint_activate(struct snd_usb_endpoint *ep);
 int  snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep);
 void snd_usb_endpoint_free(struct list_head *head);
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index fe56c9da38e9..298070e8f2d4 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -287,25 +287,32 @@ static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int v
         unsigned char buf[2];
         int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
         int timeout = 10;
-        int err;
+        int idx = 0, err;
 
         err = snd_usb_autoresume(cval->mixer->chip);
         if (err < 0)
                 return -EIO;
+        down_read(&chip->shutdown_rwsem);
         while (timeout-- > 0) {
+                if (chip->shutdown)
+                        break;
+                idx = snd_usb_ctrl_intf(chip) | (cval->id << 8);
                 if (snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
                                     USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
-                                    validx, snd_usb_ctrl_intf(chip) | (cval->id << 8),
-                                    buf, val_len) >= val_len) {
+                                    validx, idx, buf, val_len) >= val_len) {
                         *value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
-                        snd_usb_autosuspend(cval->mixer->chip);
-                        return 0;
+                        err = 0;
+                        goto out;
                 }
         }
-        snd_usb_autosuspend(cval->mixer->chip);
         snd_printdd(KERN_ERR "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
-                    request, validx, snd_usb_ctrl_intf(chip) | (cval->id << 8), cval->val_type);
-        return -EINVAL;
+                    request, validx, idx, cval->val_type);
+        err = -EINVAL;
+
+ out:
+        up_read(&chip->shutdown_rwsem);
+        snd_usb_autosuspend(cval->mixer->chip);
+        return err;
 }
 
 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret)
@@ -313,7 +320,7 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v
         struct snd_usb_audio *chip = cval->mixer->chip;
         unsigned char buf[2 + 3*sizeof(__u16)]; /* enough space for one range */
         unsigned char *val;
-        int ret, size;
+        int idx = 0, ret, size;
         __u8 bRequest;
 
         if (request == UAC_GET_CUR) {
@@ -330,16 +337,22 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v
         if (ret)
                 goto error;
 
-        ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
+        down_read(&chip->shutdown_rwsem);
+        if (chip->shutdown)
+                ret = -ENODEV;
+        else {
+                idx = snd_usb_ctrl_intf(chip) | (cval->id << 8);
+                ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
                               USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
-                              validx, snd_usb_ctrl_intf(chip) | (cval->id << 8),
-                              buf, size);
+                              validx, idx, buf, size);
+        }
+        up_read(&chip->shutdown_rwsem);
         snd_usb_autosuspend(chip);
 
         if (ret < 0) {
 error:
                 snd_printk(KERN_ERR "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
-                           request, validx, snd_usb_ctrl_intf(chip) | (cval->id << 8), cval->val_type);
+                           request, validx, idx, cval->val_type);
                 return ret;
         }
 
@@ -417,7 +430,7 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
 {
         struct snd_usb_audio *chip = cval->mixer->chip;
         unsigned char buf[2];
-        int val_len, err, timeout = 10;
+        int idx = 0, val_len, err, timeout = 10;
 
         if (cval->mixer->protocol == UAC_VERSION_1) {
                 val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
@@ -440,19 +453,27 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
         err = snd_usb_autoresume(chip);
         if (err < 0)
                 return -EIO;
-        while (timeout-- > 0)
+        down_read(&chip->shutdown_rwsem);
+        while (timeout-- > 0) {
+                if (chip->shutdown)
+                        break;
+                idx = snd_usb_ctrl_intf(chip) | (cval->id << 8);
                 if (snd_usb_ctl_msg(chip->dev,
                                     usb_sndctrlpipe(chip->dev, 0), request,
                                     USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
-                                    validx, snd_usb_ctrl_intf(chip) | (cval->id << 8),
-                                    buf, val_len) >= 0) {
-                        snd_usb_autosuspend(chip);
-                        return 0;
+                                    validx, idx, buf, val_len) >= 0) {
+                        err = 0;
+                        goto out;
                 }
-        snd_usb_autosuspend(chip);
+        }
         snd_printdd(KERN_ERR "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
-                    request, validx, snd_usb_ctrl_intf(chip) | (cval->id << 8), cval->val_type, buf[0], buf[1]);
-        return -EINVAL;
+                    request, validx, idx, cval->val_type, buf[0], buf[1]);
+        err = -EINVAL;
+
+ out:
+        up_read(&chip->shutdown_rwsem);
+        snd_usb_autosuspend(chip);
+        return err;
 }
 
 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval, int validx, int value)
diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index 690000db0ec0..ae2b71435220 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -283,6 +283,11 @@ static int snd_audigy2nx_led_put(struct snd_kcontrol *kcontrol, struct snd_ctl_e
         if (value > 1)
                 return -EINVAL;
         changed = value != mixer->audigy2nx_leds[index];
+        down_read(&mixer->chip->shutdown_rwsem);
+        if (mixer->chip->shutdown) {
+                err = -ENODEV;
+                goto out;
+        }
         if (mixer->chip->usb_id == USB_ID(0x041e, 0x3042))
                 err = snd_usb_ctl_msg(mixer->chip->dev,
                               usb_sndctrlpipe(mixer->chip->dev, 0), 0x24,
@@ -299,6 +304,8 @@ static int snd_audigy2nx_led_put(struct snd_kcontrol *kcontrol, struct snd_ctl_e
                               usb_sndctrlpipe(mixer->chip->dev, 0), 0x24,
                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
                               value, index + 2, NULL, 0);
+ out:
+        up_read(&mixer->chip->shutdown_rwsem);
         if (err < 0)
                 return err;
         mixer->audigy2nx_leds[index] = value;
@@ -392,11 +399,16 @@ static void snd_audigy2nx_proc_read(struct snd_info_entry *entry,
 
         for (i = 0; jacks[i].name; ++i) {
                 snd_iprintf(buffer, "%s: ", jacks[i].name);
-                err = snd_usb_ctl_msg(mixer->chip->dev,
+                down_read(&mixer->chip->shutdown_rwsem);
+                if (mixer->chip->shutdown)
+                        err = 0;
+                else
+                        err = snd_usb_ctl_msg(mixer->chip->dev,
                                       usb_rcvctrlpipe(mixer->chip->dev, 0),
                                       UAC_GET_MEM, USB_DIR_IN | USB_TYPE_CLASS |
                                       USB_RECIP_INTERFACE, 0,
                                       jacks[i].unitid << 8, buf, 3);
+                up_read(&mixer->chip->shutdown_rwsem);
                 if (err == 3 && (buf[0] == 3 || buf[0] == 6))
                         snd_iprintf(buffer, "%02x %02x\n", buf[1], buf[2]);
                 else
@@ -426,10 +438,15 @@ static int snd_xonar_u1_switch_put(struct snd_kcontrol *kcontrol,
         else
                 new_status = old_status & ~0x02;
         changed = new_status != old_status;
-        err = snd_usb_ctl_msg(mixer->chip->dev,
+        down_read(&mixer->chip->shutdown_rwsem);
+        if (mixer->chip->shutdown)
+                err = -ENODEV;
+        else
+                err = snd_usb_ctl_msg(mixer->chip->dev,
                               usb_sndctrlpipe(mixer->chip->dev, 0), 0x08,
                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
                               50, 0, &new_status, 1);
+        up_read(&mixer->chip->shutdown_rwsem);
         if (err < 0)
                 return err;
         mixer->xonar_u1_status = new_status;
@@ -468,11 +485,17 @@ static int snd_nativeinstruments_control_get(struct snd_kcontrol *kcontrol,
         u8 bRequest = (kcontrol->private_value >> 16) & 0xff;
         u16 wIndex = kcontrol->private_value & 0xffff;
         u8 tmp;
+        int ret;
 
-        int ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), bRequest,
+        down_read(&mixer->chip->shutdown_rwsem);
+        if (mixer->chip->shutdown)
+                ret = -ENODEV;
+        else
+                ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), bRequest,
                                   USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
                                   0, cpu_to_le16(wIndex),
                                   &tmp, sizeof(tmp), 1000);
+        up_read(&mixer->chip->shutdown_rwsem);
 
         if (ret < 0) {
                 snd_printk(KERN_ERR
@@ -493,11 +516,17 @@ static int snd_nativeinstruments_control_put(struct snd_kcontrol *kcontrol,
         u8 bRequest = (kcontrol->private_value >> 16) & 0xff;
         u16 wIndex = kcontrol->private_value & 0xffff;
         u16 wValue = ucontrol->value.integer.value[0];
+        int ret;
 
-        int ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), bRequest,
+        down_read(&mixer->chip->shutdown_rwsem);
+        if (mixer->chip->shutdown)
+                ret = -ENODEV;
+        else
+                ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), bRequest,
                                   USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
                                   cpu_to_le16(wValue), cpu_to_le16(wIndex),
                                   NULL, 0, 1000);
+        up_read(&mixer->chip->shutdown_rwsem);
 
         if (ret < 0) {
                 snd_printk(KERN_ERR
@@ -656,11 +685,16 @@ static int snd_ftu_eff_switch_get(struct snd_kcontrol *kctl,
                 return -EINVAL;
 
 
-        err = snd_usb_ctl_msg(chip->dev,
+        down_read(&mixer->chip->shutdown_rwsem);
+        if (mixer->chip->shutdown)
+                err = -ENODEV;
+        else
+                err = snd_usb_ctl_msg(chip->dev,
                         usb_rcvctrlpipe(chip->dev, 0), UAC_GET_CUR,
                         USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
                         validx << 8, snd_usb_ctrl_intf(chip) | (id << 8),
                         value, val_len);
+        up_read(&mixer->chip->shutdown_rwsem);
         if (err < 0)
                 return err;
 
@@ -703,11 +737,16 @@ static int snd_ftu_eff_switch_put(struct snd_kcontrol *kctl,
 
         if (!pval->is_cached) {
                 /* Read current value */
-                err = snd_usb_ctl_msg(chip->dev,
+                down_read(&mixer->chip->shutdown_rwsem);
+                if (mixer->chip->shutdown)
+                        err = -ENODEV;
+                else
+                        err = snd_usb_ctl_msg(chip->dev,
                                 usb_rcvctrlpipe(chip->dev, 0), UAC_GET_CUR,
                                 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
                                 validx << 8, snd_usb_ctrl_intf(chip) | (id << 8),
                                 value, val_len);
+                up_read(&mixer->chip->shutdown_rwsem);
                 if (err < 0)
                         return err;
 
@@ -719,11 +758,16 @@ static int snd_ftu_eff_switch_put(struct snd_kcontrol *kctl,
         if (cur_val != new_val) {
                 value[0] = new_val;
                 value[1] = 0;
-                err = snd_usb_ctl_msg(chip->dev,
+                down_read(&mixer->chip->shutdown_rwsem);
+                if (mixer->chip->shutdown)
+                        err = -ENODEV;
+                else
+                        err = snd_usb_ctl_msg(chip->dev,
                                 usb_sndctrlpipe(chip->dev, 0), UAC_SET_CUR,
                                 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
                                 validx << 8, snd_usb_ctrl_intf(chip) | (id << 8),
                                 value, val_len);
+                up_read(&mixer->chip->shutdown_rwsem);
                 if (err < 0)
                         return err;
 
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index 55e19e1b80ec..5c12a3fe8c3e 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -71,6 +71,8 @@ static snd_pcm_uframes_t snd_usb_pcm_pointer(struct snd_pcm_substream *substream
         unsigned int hwptr_done;
 
         subs = (struct snd_usb_substream *)substream->runtime->private_data;
+        if (subs->stream->chip->shutdown)
+                return SNDRV_PCM_POS_XRUN;
         spin_lock(&subs->lock);
         hwptr_done = subs->hwptr_done;
         substream->runtime->delay = snd_usb_pcm_delay(subs,
@@ -444,7 +446,6 @@ static int configure_endpoint(struct snd_usb_substream *subs)
 {
         int ret;
 
-        mutex_lock(&subs->stream->chip->shutdown_mutex);
         /* format changed */
         stop_endpoints(subs, 0, 0, 0);
         ret = snd_usb_endpoint_set_params(subs->data_endpoint,
@@ -455,7 +456,7 @@ static int configure_endpoint(struct snd_usb_substream *subs)
                                           subs->cur_audiofmt,
                                           subs->sync_endpoint);
         if (ret < 0)
-                goto unlock;
+                return ret;
 
         if (subs->sync_endpoint)
                 ret = snd_usb_endpoint_set_params(subs->data_endpoint,
@@ -465,9 +466,6 @@ static int configure_endpoint(struct snd_usb_substream *subs)
                                                   subs->cur_rate,
                                                   subs->cur_audiofmt,
                                                   NULL);
-
-unlock:
-        mutex_unlock(&subs->stream->chip->shutdown_mutex);
         return ret;
 }
 
@@ -505,7 +503,13 @@ static int snd_usb_hw_params(struct snd_pcm_substream *substream,
                 return -EINVAL;
         }
 
-        if ((ret = set_format(subs, fmt)) < 0)
+        down_read(&subs->stream->chip->shutdown_rwsem);
+        if (subs->stream->chip->shutdown)
+                ret = -ENODEV;
+        else
+                ret = set_format(subs, fmt);
+        up_read(&subs->stream->chip->shutdown_rwsem);
+        if (ret < 0)
                 return ret;
 
         subs->interface = fmt->iface;
@@ -527,10 +531,12 @@ static int snd_usb_hw_free(struct snd_pcm_substream *substream)
         subs->cur_audiofmt = NULL;
         subs->cur_rate = 0;
         subs->period_bytes = 0;
-        mutex_lock(&subs->stream->chip->shutdown_mutex);
-        stop_endpoints(subs, 0, 1, 1);
-        deactivate_endpoints(subs);
-        mutex_unlock(&subs->stream->chip->shutdown_mutex);
+        down_read(&subs->stream->chip->shutdown_rwsem);
+        if (!subs->stream->chip->shutdown) {
+                stop_endpoints(subs, 0, 1, 1);
+                deactivate_endpoints(subs);
+        }
+        up_read(&subs->stream->chip->shutdown_rwsem);
         return snd_pcm_lib_free_vmalloc_buffer(substream);
 }
 
@@ -552,12 +558,22 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
                 return -ENXIO;
         }
 
-        if (snd_BUG_ON(!subs->data_endpoint))
-                return -EIO;
+        down_read(&subs->stream->chip->shutdown_rwsem);
+        if (subs->stream->chip->shutdown) {
+                ret = -ENODEV;
+                goto unlock;
+        }
+        if (snd_BUG_ON(!subs->data_endpoint)) {
+                ret = -EIO;
+                goto unlock;
+        }
+
+        snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
+        snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
 
         ret = set_format(subs, subs->cur_audiofmt);
         if (ret < 0)
-                return ret;
+                goto unlock;
 
         iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
         alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
@@ -567,12 +583,12 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
                                        subs->cur_audiofmt,
                                        subs->cur_rate);
         if (ret < 0)
-                return ret;
+                goto unlock;
 
         if (subs->need_setup_ep) {
                 ret = configure_endpoint(subs);
                 if (ret < 0)
-                        return ret;
+                        goto unlock;
                 subs->need_setup_ep = false;
         }
 
@@ -592,9 +608,11 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
         /* for playback, submit the URBs now; otherwise, the first hwptr_done
          * updates for all URBs would happen at the same time when starting */
         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
-                return start_endpoints(subs, 1);
+                ret = start_endpoints(subs, 1);
 
-        return 0;
+ unlock:
+        up_read(&subs->stream->chip->shutdown_rwsem);
+        return ret;
 }
 
 static struct snd_pcm_hardware snd_usb_hardware =
@@ -647,7 +665,7 @@ static int hw_check_valid_format(struct snd_usb_substream *subs,
                 return 0;
         }
         /* check whether the period time is >= the data packet interval */
-        if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL) {
+        if (subs->speed != USB_SPEED_FULL) {
                 ptime = 125 * (1 << fp->datainterval);
                 if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
                         hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
@@ -925,7 +943,7 @@ static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substre
                 return err;
 
         param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
-        if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
+        if (subs->speed == USB_SPEED_FULL)
                 /* full speed devices have fixed data packet interval */
                 ptmin = 1000;
         if (ptmin == 1000)
diff --git a/sound/usb/proc.c b/sound/usb/proc.c
index ebc1a5b5b3f1..d218f763501f 100644
--- a/sound/usb/proc.c
+++ b/sound/usb/proc.c
@@ -108,7 +108,7 @@ static void proc_dump_substream_formats(struct snd_usb_substream *subs, struct s
                         }
                         snd_iprintf(buffer, "\n");
                 }
-                if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL)
+                if (subs->speed != USB_SPEED_FULL)
                         snd_iprintf(buffer, "    Data packet interval: %d us\n",
                                     125 * (1 << fp->datainterval));
                 // snd_iprintf(buffer, "    Max Packet Size = %d\n", fp->maxpacksize);
@@ -124,7 +124,7 @@ static void proc_dump_ep_status(struct snd_usb_substream *subs,
                 return;
         snd_iprintf(buffer, "    Packet Size = %d\n", ep->curpacksize);
         snd_iprintf(buffer, "    Momentary freq = %u Hz (%#x.%04x)\n",
-                    snd_usb_get_speed(subs->dev) == USB_SPEED_FULL
+                    subs->speed == USB_SPEED_FULL
                     ? get_full_speed_hz(ep->freqm)
                     : get_high_speed_hz(ep->freqm),
                     ep->freqm >> 16, ep->freqm & 0xffff);
diff --git a/sound/usb/stream.c b/sound/usb/stream.c
index 083ed81160e5..1de0c8c002a8 100644
--- a/sound/usb/stream.c
+++ b/sound/usb/stream.c
@@ -90,6 +90,7 @@ static void snd_usb_init_substream(struct snd_usb_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);
 
diff --git a/sound/usb/usbaudio.h b/sound/usb/usbaudio.h
index b8233ebe250f..ef42797f56fb 100644
--- a/sound/usb/usbaudio.h
+++ b/sound/usb/usbaudio.h
@@ -37,7 +37,7 @@ struct snd_usb_audio {
         struct usb_interface *pm_intf;
         u32 usb_id;
         struct mutex mutex;
-        struct mutex shutdown_mutex;
+        struct rw_semaphore shutdown_rwsem;
         unsigned int shutdown:1;
         unsigned int probing:1;
         unsigned int autosuspended:1;