ALSA: Allow to pass the device object to snd_register_device*()
This is a preliminary patch for the further work on embedding struct
device into each sound device instance. It changes
snd_register_device*() helpers to receive the device object directly
for skipping creating a device there.
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/core.h b/include/sound/core.h
index 1df3f2f..39d1423 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -186,6 +186,7 @@
int type; /* SNDRV_DEVICE_TYPE_XXX */
int card; /* card number */
int device; /* device number */
+ bool created;
const struct file_operations *f_ops; /* file operations */
void *private_data; /* private data for f_ops->open */
struct device *dev; /* device for sysfs */
@@ -206,12 +207,10 @@
void snd_request_card(int card);
-int snd_register_device_for_dev(int type, struct snd_card *card,
- int dev,
+int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
const struct file_operations *f_ops,
- void *private_data,
- const char *name,
- struct device *device);
+ void *private_data, struct device *device,
+ struct device *parent, const char *name);
/**
* snd_register_device - Register the ALSA device file for the card
@@ -236,8 +235,9 @@
const char *name)
{
return snd_register_device_for_dev(type, card, dev, f_ops,
- private_data, name,
- snd_card_get_device_link(card));
+ private_data, NULL,
+ snd_card_get_device_link(card),
+ name);
}
int snd_unregister_device(int type, struct snd_card *card, int dev);
diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c
index 69459e5..85096a1 100644
--- a/sound/core/hwdep.c
+++ b/sound/core/hwdep.c
@@ -433,7 +433,8 @@
dev = snd_card_get_device_link(hwdep->card);
err = snd_register_device_for_dev(SNDRV_DEVICE_TYPE_HWDEP,
hwdep->card, hwdep->device,
- &snd_hwdep_f_ops, hwdep, name, dev);
+ &snd_hwdep_f_ops, hwdep,
+ NULL, dev, name);
if (err < 0) {
dev_err(dev,
"unable to register hardware dependent device %i:%i\n",
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index cfc56c8..dba5180 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -1115,7 +1115,7 @@
err = snd_register_device_for_dev(devtype, pcm->card,
pcm->device,
&snd_pcm_f_ops[cidx],
- pcm, str, dev);
+ pcm, NULL, dev, str);
if (err < 0) {
list_del(&pcm->list);
mutex_unlock(®ister_mutex);
diff --git a/sound/core/sound.c b/sound/core/sound.c
index f133306..ea1af1a 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -248,8 +248,9 @@
* @dev: the device index
* @f_ops: the file operations
* @private_data: user pointer for f_ops->open()
- * @name: the device file name
- * @device: the &struct device to link this new device to
+ * @device: the device to register, NULL to create a new one
+ * @parent: the &struct device to link this new device to (only for device=NULL)
+ * @name: the device file name (only for device=NULL)
*
* Registers an ALSA device file for the given card.
* The operators have to be set in reg parameter.
@@ -258,14 +259,13 @@
*/
int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
const struct file_operations *f_ops,
- void *private_data,
- const char *name, struct device *device)
+ void *private_data, struct device *device,
+ struct device *parent, const char *name)
{
int minor;
+ int err = 0;
struct snd_minor *preg;
- if (snd_BUG_ON(!name))
- return -EINVAL;
preg = kmalloc(sizeof *preg, GFP_KERNEL);
if (preg == NULL)
return -ENOMEM;
@@ -284,23 +284,32 @@
minor = -EBUSY;
#endif
if (minor < 0) {
- mutex_unlock(&sound_mutex);
- kfree(preg);
- return minor;
- }
- snd_minors[minor] = preg;
- preg->dev = device_create(sound_class, device, MKDEV(major, minor),
- private_data, "%s", name);
- if (IS_ERR(preg->dev)) {
- snd_minors[minor] = NULL;
- mutex_unlock(&sound_mutex);
- minor = PTR_ERR(preg->dev);
- kfree(preg);
- return minor;
+ err = minor;
+ goto error;
}
+ if (device) {
+ preg->created = false;
+ preg->dev = device;
+ device->devt = MKDEV(major, minor);
+ err = device_add(device);
+ } else {
+ preg->created = true;
+ preg->dev = device_create(sound_class, parent,
+ MKDEV(major, minor), private_data,
+ "%s", name);
+ if (IS_ERR(preg->dev))
+ err = PTR_ERR(preg->dev);
+ }
+ if (err < 0)
+ goto error;
+
+ snd_minors[minor] = preg;
+ error:
mutex_unlock(&sound_mutex);
- return 0;
+ if (err < 0)
+ kfree(preg);
+ return err;
}
EXPORT_SYMBOL(snd_register_device_for_dev);
@@ -337,6 +346,7 @@
int snd_unregister_device(int type, struct snd_card *card, int dev)
{
int minor;
+ struct snd_minor *preg;
mutex_lock(&sound_mutex);
minor = find_snd_minor(type, card, dev);
@@ -345,7 +355,11 @@
return -EINVAL;
}
- device_destroy(sound_class, MKDEV(major, minor));
+ preg = snd_minors[minor];
+ if (preg && !preg->created)
+ device_del(preg->dev);
+ else
+ device_destroy(sound_class, MKDEV(major, minor));
kfree(snd_minors[minor]);
snd_minors[minor] = NULL;