11 files changed, 151 insertions, 38 deletions

diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c
index c40ae573346d..ad11dc994792 100644
--- a/sound/core/compress_offload.c
+++ b/sound/core/compress_offload.c
@@ -100,12 +100,15 @@ static int snd_compr_open(struct inode *inode, struct file *f)
 
         if (dirn != compr->direction) {
                 pr_err("this device doesn't support this direction\n");
+                snd_card_unref(compr->card);
                 return -EINVAL;
         }
 
         data = kzalloc(sizeof(*data), GFP_KERNEL);
-        if (!data)
+        if (!data) {
+                snd_card_unref(compr->card);
                 return -ENOMEM;
+        }
         data->stream.ops = compr->ops;
         data->stream.direction = dirn;
         data->stream.private_data = compr->private_data;
@@ -113,6 +116,7 @@ static int snd_compr_open(struct inode *inode, struct file *f)
         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
         if (!runtime) {
                 kfree(data);
+                snd_card_unref(compr->card);
                 return -ENOMEM;
         }
         runtime->state = SNDRV_PCM_STATE_OPEN;
@@ -126,7 +130,8 @@ static int snd_compr_open(struct inode *inode, struct file *f)
                 kfree(runtime);
                 kfree(data);
         }
-        return ret;
+        snd_card_unref(compr->card);
+        return 0;
 }
 
 static int snd_compr_free(struct inode *inode, struct file *f)
diff --git a/sound/core/control.c b/sound/core/control.c
index 7e86a5b9f3b5..8c7c2c9bba61 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -86,6 +86,7 @@ static int snd_ctl_open(struct inode *inode, struct file *file)
         write_lock_irqsave(&card->ctl_files_rwlock, flags);
         list_add_tail(&ctl->list, &card->ctl_files);
         write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
+        snd_card_unref(card);
         return 0;
 
       __error:
@@ -93,6 +94,8 @@ static int snd_ctl_open(struct inode *inode, struct file *file)
       __error2:
         snd_card_file_remove(card, file);
       __error1:
+        if (card)
+                snd_card_unref(card);
         return err;
 }
 
@@ -1434,6 +1437,8 @@ static ssize_t snd_ctl_read(struct file *file, char __user *buffer,
                         spin_unlock_irq(&ctl->read_lock);
                         schedule();
                         remove_wait_queue(&ctl->change_sleep, &wait);
+                        if (ctl->card->shutdown)
+                                return -ENODEV;
                         if (signal_pending(current))
                                 return -ERESTARTSYS;
                         spin_lock_irq(&ctl->read_lock);
diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c
index 75ea16f35b1a..3f7f6628cf7b 100644
--- a/sound/core/hwdep.c
+++ b/sound/core/hwdep.c
@@ -100,8 +100,10 @@ static int snd_hwdep_open(struct inode *inode, struct file * file)
         if (hw == NULL)
                 return -ENODEV;
 
-        if (!try_module_get(hw->card->module))
+        if (!try_module_get(hw->card->module)) {
+                snd_card_unref(hw->card);
                 return -EFAULT;
+        }
 
         init_waitqueue_entry(&wait, current);
         add_wait_queue(&hw->open_wait, &wait);
@@ -129,6 +131,10 @@ static int snd_hwdep_open(struct inode *inode, struct file * file)
                 mutex_unlock(&hw->open_mutex);
                 schedule();
                 mutex_lock(&hw->open_mutex);
+                if (hw->card->shutdown) {
+                        err = -ENODEV;
+                        break;
+                }
                 if (signal_pending(current)) {
                         err = -ERESTARTSYS;
                         break;
@@ -148,6 +154,7 @@ static int snd_hwdep_open(struct inode *inode, struct file * file)
         mutex_unlock(&hw->open_mutex);
         if (err < 0)
                 module_put(hw->card->module);
+        snd_card_unref(hw->card);
         return err;
 }
 
@@ -459,12 +466,15 @@ static int snd_hwdep_dev_disconnect(struct snd_device *device)
                 mutex_unlock(&register_mutex);
                 return -EINVAL;
         }
+        mutex_lock(&hwdep->open_mutex);
+        wake_up(&hwdep->open_wait);
 #ifdef CONFIG_SND_OSSEMUL
         if (hwdep->ossreg)
                 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
 #endif
         snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
         list_del_init(&hwdep->list);
+        mutex_unlock(&hwdep->open_mutex);
         mutex_unlock(&register_mutex);
         return 0;
 }
diff --git a/sound/core/init.c b/sound/core/init.c
index d8ec849af128..7b012d15c2cf 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -213,6 +213,7 @@ int snd_card_create(int idx, const char *xid,
         spin_lock_init(&card->files_lock);
         INIT_LIST_HEAD(&card->files_list);
         init_waitqueue_head(&card->shutdown_sleep);
+        atomic_set(&card->refcount, 0);
 #ifdef CONFIG_PM
         mutex_init(&card->power_lock);
         init_waitqueue_head(&card->power_sleep);
@@ -446,21 +447,36 @@ static int snd_card_do_free(struct snd_card *card)
         return 0;
 }
 
+/**
+ * snd_card_unref - release the reference counter
+ * @card: the card instance
+ *
+ * Decrements the reference counter.  When it reaches to zero, wake up
+ * the sleeper and call the destructor if needed.
+ */
+void snd_card_unref(struct snd_card *card)
+{
+        if (atomic_dec_and_test(&card->refcount)) {
+                wake_up(&card->shutdown_sleep);
+                if (card->free_on_last_close)
+                        snd_card_do_free(card);
+        }
+}
+EXPORT_SYMBOL(snd_card_unref);
+
 int snd_card_free_when_closed(struct snd_card *card)
 {
-        int free_now = 0;
-        int ret = snd_card_disconnect(card);
-        if (ret)
-                return ret;
+        int ret;
 
-        spin_lock(&card->files_lock);
-        if (list_empty(&card->files_list))
-                free_now = 1;
-        else
-                card->free_on_last_close = 1;
-        spin_unlock(&card->files_lock);
+        atomic_inc(&card->refcount);
+        ret = snd_card_disconnect(card);
+        if (ret) {
+                atomic_dec(&card->refcount);
+                return ret;
+        }
 
-        if (free_now)
+        card->free_on_last_close = 1;
+        if (atomic_dec_and_test(&card->refcount))
                 snd_card_do_free(card);
         return 0;
 }
@@ -474,7 +490,7 @@ int snd_card_free(struct snd_card *card)
                 return ret;
 
         /* wait, until all devices are ready for the free operation */
-        wait_event(card->shutdown_sleep, list_empty(&card->files_list));
+        wait_event(card->shutdown_sleep, !atomic_read(&card->refcount));
         snd_card_do_free(card);
         return 0;
 }
@@ -886,6 +902,7 @@ int snd_card_file_add(struct snd_card *card, struct file *file)
                 return -ENODEV;
         }
         list_add(&mfile->list, &card->files_list);
+        atomic_inc(&card->refcount);
         spin_unlock(&card->files_lock);
         return 0;
 }
@@ -908,7 +925,6 @@ EXPORT_SYMBOL(snd_card_file_add);
 int snd_card_file_remove(struct snd_card *card, struct file *file)
 {
         struct snd_monitor_file *mfile, *found = NULL;
-        int last_close = 0;
 
         spin_lock(&card->files_lock);
         list_for_each_entry(mfile, &card->files_list, list) {
@@ -923,19 +939,13 @@ int snd_card_file_remove(struct snd_card *card, struct file *file)
                         break;
                 }
         }
-        if (list_empty(&card->files_list))
-                last_close = 1;
         spin_unlock(&card->files_lock);
-        if (last_close) {
-                wake_up(&card->shutdown_sleep);
-                if (card->free_on_last_close)
-                        snd_card_do_free(card);
-        }
         if (!found) {
                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
                 return -ENOENT;
         }
         kfree(found);
+        snd_card_unref(card);
         return 0;
 }
 
diff --git a/sound/core/oss/mixer_oss.c b/sound/core/oss/mixer_oss.c
index 29f6ded02555..e8a1d18774b2 100644
--- a/sound/core/oss/mixer_oss.c
+++ b/sound/core/oss/mixer_oss.c
@@ -52,14 +52,19 @@ static int snd_mixer_oss_open(struct inode *inode, struct file *file)
                                          SNDRV_OSS_DEVICE_TYPE_MIXER);
         if (card == NULL)
                 return -ENODEV;
-        if (card->mixer_oss == NULL)
+        if (card->mixer_oss == NULL) {
+                snd_card_unref(card);
                 return -ENODEV;
+        }
         err = snd_card_file_add(card, file);
-        if (err < 0)
+        if (err < 0) {
+                snd_card_unref(card);
                 return err;
+        }
         fmixer = kzalloc(sizeof(*fmixer), GFP_KERNEL);
         if (fmixer == NULL) {
                 snd_card_file_remove(card, file);
+                snd_card_unref(card);
                 return -ENOMEM;
         }
         fmixer->card = card;
@@ -68,8 +73,10 @@ static int snd_mixer_oss_open(struct inode *inode, struct file *file)
         if (!try_module_get(card->module)) {
                 kfree(fmixer);
                 snd_card_file_remove(card, file);
+                snd_card_unref(card);
                 return -EFAULT;
         }
+        snd_card_unref(card);
         return 0;
 }
 
diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index 08fde0060fd9..4c1cc51772e6 100644
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -2441,6 +2441,10 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file)
                 mutex_unlock(&pcm->open_mutex);
                 schedule();
                 mutex_lock(&pcm->open_mutex);
+                if (pcm->card->shutdown) {
+                        err = -ENODEV;
+                        break;
+                }
                 if (signal_pending(current)) {
                         err = -ERESTARTSYS;
                         break;
@@ -2450,6 +2454,7 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file)
         mutex_unlock(&pcm->open_mutex);
         if (err < 0)
                 goto __error;
+        snd_card_unref(pcm->card);
         return err;
 
       __error:
@@ -2457,6 +2462,8 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file)
       __error2:
         snd_card_file_remove(pcm->card, file);
       __error1:
+        if (pcm)
+                snd_card_unref(pcm->card);
         return err;
 }
 
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index f2991940b271..030102caeee9 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -1086,11 +1086,19 @@ static int snd_pcm_dev_disconnect(struct snd_device *device)
         if (list_empty(&pcm->list))
                 goto unlock;
 
+        mutex_lock(&pcm->open_mutex);
+        wake_up(&pcm->open_wait);
         list_del_init(&pcm->list);
         for (cidx = 0; cidx < 2; cidx++)
-                for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
-                        if (substream->runtime)
+                for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
+                        snd_pcm_stream_lock_irq(substream);
+                        if (substream->runtime) {
                                 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
+                                wake_up(&substream->runtime->sleep);
+                                wake_up(&substream->runtime->tsleep);
+                        }
+                        snd_pcm_stream_unlock_irq(substream);
+                }
         list_for_each_entry(notify, &snd_pcm_notify_list, list) {
                 notify->n_disconnect(pcm);
         }
@@ -1110,6 +1118,7 @@ static int snd_pcm_dev_disconnect(struct snd_device *device)
                         pcm->streams[cidx].chmap_kctl = NULL;
                 }
         }
+        mutex_unlock(&pcm->open_mutex);
  unlock:
         mutex_unlock(&register_mutex);
         return 0;
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 5e12e5bacbba..f9ddecf2f4cd 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -369,6 +369,14 @@ static int period_to_usecs(struct snd_pcm_runtime *runtime)
         return usecs;
 }
 
+static void snd_pcm_set_state(struct snd_pcm_substream *substream, int state)
+{
+        snd_pcm_stream_lock_irq(substream);
+        if (substream->runtime->status->state != SNDRV_PCM_STATE_DISCONNECTED)
+                substream->runtime->status->state = state;
+        snd_pcm_stream_unlock_irq(substream);
+}
+
 static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
                              struct snd_pcm_hw_params *params)
 {
@@ -452,7 +460,7 @@ static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
                 runtime->boundary *= 2;
 
         snd_pcm_timer_resolution_change(substream);
-        runtime->status->state = SNDRV_PCM_STATE_SETUP;
+        snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);
 
         if (pm_qos_request_active(&substream->latency_pm_qos_req))
                 pm_qos_remove_request(&substream->latency_pm_qos_req);
@@ -464,7 +472,7 @@ static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
         /* hardware might be unusable from this time,
            so we force application to retry to set
            the correct hardware parameter settings */
-        runtime->status->state = SNDRV_PCM_STATE_OPEN;
+        snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
         if (substream->ops->hw_free != NULL)
                 substream->ops->hw_free(substream);
         return err;
@@ -512,7 +520,7 @@ static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
                 return -EBADFD;
         if (substream->ops->hw_free)
                 result = substream->ops->hw_free(substream);
-        runtime->status->state = SNDRV_PCM_STATE_OPEN;
+        snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
         pm_qos_remove_request(&substream->latency_pm_qos_req);
         return result;
 }
@@ -1320,7 +1328,7 @@ static void snd_pcm_post_prepare(struct snd_pcm_substream *substream, int state)
 {
         struct snd_pcm_runtime *runtime = substream->runtime;
         runtime->control->appl_ptr = runtime->status->hw_ptr;
-        runtime->status->state = SNDRV_PCM_STATE_PREPARED;
+        snd_pcm_set_state(substream, SNDRV_PCM_STATE_PREPARED);
 }
 
 static struct action_ops snd_pcm_action_prepare = {
@@ -1510,6 +1518,10 @@ static int snd_pcm_drain(struct snd_pcm_substream *substream,
                 down_read(&snd_pcm_link_rwsem);
                 snd_pcm_stream_lock_irq(substream);
                 remove_wait_queue(&to_check->sleep, &wait);
+                if (card->shutdown) {
+                        result = -ENODEV;
+                        break;
+                }
                 if (tout == 0) {
                         if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
                                 result = -ESTRPIPE;
@@ -1634,6 +1646,7 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
         write_unlock_irq(&snd_pcm_link_rwlock);
         up_write(&snd_pcm_link_rwsem);
  _nolock:
+        snd_card_unref(substream1->pcm->card);
         fput_light(file, fput_needed);
         if (res < 0)
                 kfree(group);
@@ -2108,7 +2121,10 @@ static int snd_pcm_playback_open(struct inode *inode, struct file *file)
                 return err;
         pcm = snd_lookup_minor_data(iminor(inode),
                                     SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
-        return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
+        err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
+        if (pcm)
+                snd_card_unref(pcm->card);
+        return err;
 }
 
 static int snd_pcm_capture_open(struct inode *inode, struct file *file)
@@ -2119,7 +2135,10 @@ static int snd_pcm_capture_open(struct inode *inode, struct file *file)
                 return err;
         pcm = snd_lookup_minor_data(iminor(inode),
                                     SNDRV_DEVICE_TYPE_PCM_CAPTURE);
-        return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
+        err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
+        if (pcm)
+                snd_card_unref(pcm->card);
+        return err;
 }
 
 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
@@ -2156,6 +2175,10 @@ static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
                 mutex_unlock(&pcm->open_mutex);
                 schedule();
                 mutex_lock(&pcm->open_mutex);
+                if (pcm->card->shutdown) {
+                        err = -ENODEV;
+                        break;
+                }
                 if (signal_pending(current)) {
                         err = -ERESTARTSYS;
                         break;
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index ebf6e49ad3d4..1bb95aeea084 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -379,8 +379,10 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
         if (rmidi == NULL)
                 return -ENODEV;
 
-        if (!try_module_get(rmidi->card->module))
+        if (!try_module_get(rmidi->card->module)) {
+                snd_card_unref(rmidi->card);
                 return -ENXIO;
+        }
 
         mutex_lock(&rmidi->open_mutex);
         card = rmidi->card;
@@ -422,6 +424,10 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
                 mutex_unlock(&rmidi->open_mutex);
                 schedule();
                 mutex_lock(&rmidi->open_mutex);
+                if (rmidi->card->shutdown) {
+                        err = -ENODEV;
+                        break;
+                }
                 if (signal_pending(current)) {
                         err = -ERESTARTSYS;
                         break;
@@ -440,6 +446,7 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
 #endif
         file->private_data = rawmidi_file;
         mutex_unlock(&rmidi->open_mutex);
+        snd_card_unref(rmidi->card);
         return 0;
 
  __error:
@@ -447,6 +454,7 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
  __error_card:
         mutex_unlock(&rmidi->open_mutex);
         module_put(rmidi->card->module);
+        snd_card_unref(rmidi->card);
         return err;
 }
 
@@ -991,6 +999,8 @@ static ssize_t snd_rawmidi_read(struct file *file, char __user *buf, size_t coun
                         spin_unlock_irq(&runtime->lock);
                         schedule();
                         remove_wait_queue(&runtime->sleep, &wait);
+                        if (rfile->rmidi->card->shutdown)
+                                return -ENODEV;
                         if (signal_pending(current))
                                 return result > 0 ? result : -ERESTARTSYS;
                         if (!runtime->avail)
@@ -1234,6 +1244,8 @@ static ssize_t snd_rawmidi_write(struct file *file, const char __user *buf,
                         spin_unlock_irq(&runtime->lock);
                         timeout = schedule_timeout(30 * HZ);
                         remove_wait_queue(&runtime->sleep, &wait);
+                        if (rfile->rmidi->card->shutdown)
+                                return -ENODEV;
                         if (signal_pending(current))
                                 return result > 0 ? result : -ERESTARTSYS;
                         if (!runtime->avail && !timeout)
@@ -1609,9 +1621,20 @@ static int snd_rawmidi_dev_register(struct snd_device *device)
 static int snd_rawmidi_dev_disconnect(struct snd_device *device)
 {
         struct snd_rawmidi *rmidi = device->device_data;
+        int dir;
 
         mutex_lock(&register_mutex);
+        mutex_lock(&rmidi->open_mutex);
+        wake_up(&rmidi->open_wait);
         list_del_init(&rmidi->list);
+        for (dir = 0; dir < 2; dir++) {
+                struct snd_rawmidi_substream *s;
+                list_for_each_entry(s, &rmidi->streams[dir].substreams, list) {
+                        if (s->runtime)
+                                wake_up(&s->runtime->sleep);
+                }
+        }
+
 #ifdef CONFIG_SND_OSSEMUL
         if (rmidi->ossreg) {
                 if ((int)rmidi->device == midi_map[rmidi->card->number]) {
@@ -1626,6 +1649,7 @@ static int snd_rawmidi_dev_disconnect(struct snd_device *device)
         }
 #endif /* CONFIG_SND_OSSEMUL */
         snd_unregister_device(SNDRV_DEVICE_TYPE_RAWMIDI, rmidi->card, rmidi->device);
+        mutex_unlock(&rmidi->open_mutex);
         mutex_unlock(&register_mutex);
         return 0;
 }
diff --git a/sound/core/sound.c b/sound/core/sound.c
index 643976000ce8..70ccdab74153 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -98,6 +98,10 @@ static void snd_request_other(int minor)
  *
  * Checks that a minor device with the specified type is registered, and returns
  * its user data pointer.
+ *
+ * This function increments the reference counter of the card instance
+ * if an associated instance with the given minor number and type is found.
+ * The caller must call snd_card_unref() appropriately later.
  */
 void *snd_lookup_minor_data(unsigned int minor, int type)
 {
@@ -108,9 +112,11 @@ void *snd_lookup_minor_data(unsigned int minor, int type)
                 return NULL;
         mutex_lock(&sound_mutex);
         mreg = snd_minors[minor];
-        if (mreg && mreg->type == type)
+        if (mreg && mreg->type == type) {
                 private_data = mreg->private_data;
-        else
+                if (private_data && mreg->card_ptr)
+                        atomic_inc(&mreg->card_ptr->refcount);
+        } else
                 private_data = NULL;
         mutex_unlock(&sound_mutex);
         return private_data;
@@ -275,6 +281,7 @@ int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
         preg->device = dev;
         preg->f_ops = f_ops;
         preg->private_data = private_data;
+        preg->card_ptr = card;
         mutex_lock(&sound_mutex);
 #ifdef CONFIG_SND_DYNAMIC_MINORS
         minor = snd_find_free_minor(type);
diff --git a/sound/core/sound_oss.c b/sound/core/sound_oss.c
index e9528333e36d..726a49ac9725 100644
--- a/sound/core/sound_oss.c
+++ b/sound/core/sound_oss.c
@@ -40,6 +40,9 @@
 static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];
 static DEFINE_MUTEX(sound_oss_mutex);
 
+/* NOTE: This function increments the refcount of the associated card like
+ * snd_lookup_minor_data(); the caller must call snd_card_unref() appropriately
+ */
 void *snd_lookup_oss_minor_data(unsigned int minor, int type)
 {
         struct snd_minor *mreg;
@@ -49,9 +52,11 @@ void *snd_lookup_oss_minor_data(unsigned int minor, int type)
                 return NULL;
         mutex_lock(&sound_oss_mutex);
         mreg = snd_oss_minors[minor];
-        if (mreg && mreg->type == type)
+        if (mreg && mreg->type == type) {
                 private_data = mreg->private_data;
-        else
+                if (private_data && mreg->card_ptr)
+                        atomic_inc(&mreg->card_ptr->refcount);
+        } else
                 private_data = NULL;
         mutex_unlock(&sound_oss_mutex);
         return private_data;
@@ -123,6 +128,7 @@ int snd_register_oss_device(int type, struct snd_card *card, int dev,
         preg->device = dev;
         preg->f_ops = f_ops;
         preg->private_data = private_data;
+        preg->card_ptr = card;
         mutex_lock(&sound_oss_mutex);
         snd_oss_minors[minor] = preg;
         minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);