[ALSA] Nest sound devices

Modules: ALSA Core

Make the control device parent of all other ALSA devices of a card.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

3 files changed, 11 insertions, 3 deletions

diff --git a/include/sound/core.h b/include/sound/core.h
index 90ac6132ea3b..dbe7a2c30272 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -134,6 +134,7 @@ struct snd_card {
         wait_queue_head_t shutdown_sleep;
         struct work_struct free_workq;  /* for free in workqueue */
         struct device *dev;
+        struct class_device *parent_device;
 
 #ifdef CONFIG_PM
         unsigned int power_state;       /* power state */
diff --git a/sound/core/device.c b/sound/core/device.c
index b1cf6ec56784..478264cab67e 100644
--- a/sound/core/device.c
+++ b/sound/core/device.c
@@ -193,7 +193,7 @@ int snd_device_register_all(struct snd_card *card)
         int err;
         
         snd_assert(card != NULL, return -ENXIO);
-        list_for_each(list, &card->devices) {
+        list_for_each_prev(list, &card->devices) {
                 dev = snd_device(list);
                 if (dev->state == SNDRV_DEV_BUILD && dev->ops->dev_register) {
                         if ((err = dev->ops->dev_register(dev)) < 0)
diff --git a/sound/core/sound.c b/sound/core/sound.c
index a8eda02bcf1c..2f6108deb211 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -245,6 +245,7 @@ int snd_register_device(int type, struct snd_card *card, int dev,
         int minor;
         struct snd_minor *preg;
         struct device *device = NULL;
+        struct class_device *class_device = NULL;
 
         snd_assert(name, return -EINVAL);
         preg = kmalloc(sizeof(struct snd_minor) + strlen(name) + 1, GFP_KERNEL);
@@ -272,9 +273,15 @@ int snd_register_device(int type, struct snd_card *card, int dev,
         snd_minors[minor] = preg;
         if (type != SNDRV_DEVICE_TYPE_CONTROL || preg->card >= cards_limit)
                 devfs_mk_cdev(MKDEV(major, minor), S_IFCHR | device_mode, "snd/%s", name);
-        if (card)
+        if (card) {
                 device = card->dev;
-        class_device_create(sound_class, NULL, MKDEV(major, minor), device, "%s", name);
+                class_device = card->parent_device;
+        }
+        class_device = class_device_create(sound_class, class_device,
+                                           MKDEV(major, minor), device,
+                                           "%s", name);
+        if (type == SNDRV_DEVICE_TYPE_CONTROL)
+                card->parent_device = class_device;
 
         up(&sound_mutex);
         return 0;