ALSA: core: Introduce snd_device_alloc()

Introduce a new helper, snd_device_alloc(), for allocating a struct
device that is bound with the sound class.  It's a replacement of
snd_device_initialize().

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Tested-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20230816160252.23396-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/include/sound/core.h b/include/sound/core.h
index f6e0dd6..f986fcc 100644 (file)
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -239,6 +239,7 @@ extern struct dentry *sound_debugfs_root;
 
 void snd_request_card(int card);
 
+int snd_device_alloc(struct device **dev_p, struct snd_card *card);
 void snd_device_initialize(struct device *dev, struct snd_card *card);
 
 int snd_register_device(int type, struct snd_card *card, int dev,

diff --git a/sound/core/init.c b/sound/core/init.c
index baef268..a4de9f0 100644 (file)
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -134,6 +134,37 @@ void snd_device_initialize(struct device *dev, struct snd_card *card)
 }
 EXPORT_SYMBOL_GPL(snd_device_initialize);
 
+/* the default release callback set in snd_device_alloc() */
+static void default_release_alloc(struct device *dev)
+{
+       kfree(dev);
+}
+
+/**
+ * snd_device_alloc - Allocate and initialize struct device for sound devices
+ * @dev_p: pointer to store the allocated device
+ * @card: card to assign, optional
+ *
+ * For releasing the allocated device, call put_device().
+ */
+int snd_device_alloc(struct device **dev_p, struct snd_card *card)
+{
+       struct device *dev;
+
+       *dev_p = NULL;
+       dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+       if (!dev)
+               return -ENOMEM;
+       device_initialize(dev);
+       if (card)
+               dev->parent = &card->card_dev;
+       dev->class = &sound_class;
+       dev->release = default_release_alloc;
+       *dev_p = dev;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(snd_device_alloc);
+
 static int snd_card_init(struct snd_card *card, struct device *parent,
                         int idx, const char *xid, struct module *module,
                         size_t extra_size);