Commit 9d19f48c authored by Takashi Iwai's avatar Takashi Iwai Committed by Jaroslav Kysela
Browse files

[ALSA] Add pcm_class attribute to PCM sysfs entry 



This patch adds a new attribute, pcm_class, to each PCM sysfs entry.
It's useful to detect what kind of PCM stream is, for example, HAL
can check whether it's a modem or not.

Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarJaroslav Kysela <perex@suse.cz>
parent a7da6ce5

include/sound/core.h

+4 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <linux/mutex.h>		/* struct mutex */

#include <linux/rwsem.h>		/* struct rw_semaphore */

#include <linux/pm.h>			/* pm_message_t */

#include <linux/device.h>



/* forward declarations */

#ifdef CONFIG_PCI
@@ -186,6 +187,7 @@ struct snd_minor { 
	int device;			/* device number */

	const struct file_operations *f_ops;	/* file operations */

	void *private_data;		/* private data for f_ops->open */

	struct class_device *class_dev;	/* class device for sysfs */

};



/* sound.c */
@@ -200,6 +202,8 @@ int snd_register_device(int type, struct snd_card *card, int dev, 
			const char *name);

int snd_unregister_device(int type, struct snd_card *card, int dev);

void *snd_lookup_minor_data(unsigned int minor, int type);

int snd_add_device_sysfs_file(int type, struct snd_card *card, int dev,

			      const struct class_device_attribute *attr);



#ifdef CONFIG_SND_OSSEMUL

int snd_register_oss_device(int type, struct snd_card *card, int dev,

sound/core/pcm.c

+24 −0
Original line number Diff line number Diff line
@@ -907,6 +907,28 @@ void snd_pcm_detach_substream(struct snd_pcm_substream *substream) 
	substream->pstr->substream_opened--;

}



static ssize_t show_pcm_class(struct class_device *class_device, char *buf)

{

	struct snd_pcm *pcm;

	const char *str;

	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {

		[SNDRV_PCM_CLASS_GENERIC] = "generic",

		[SNDRV_PCM_CLASS_MULTI] = "multi",

		[SNDRV_PCM_CLASS_MODEM] = "modem",

		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",

	};



	if (! (pcm = class_get_devdata(class_device)) ||

	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)

		str = "none";

	else

		str = strs[pcm->dev_class];

        return snprintf(buf, PAGE_SIZE, "%s\n", str);

}



static struct class_device_attribute pcm_attrs =

	__ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);



static int snd_pcm_dev_register(struct snd_device *device)

{

	int cidx, err;
@@ -945,6 +967,8 @@ static int snd_pcm_dev_register(struct snd_device *device) 
			mutex_unlock(&register_mutex);

			return err;

		}

		snd_add_device_sysfs_file(devtype, pcm->card, pcm->device,

					  &pcm_attrs);

		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)

			snd_pcm_timer_init(substream);

	}

sound/core/sound.c

+44 −12
Original line number Diff line number Diff line
@@ -268,7 +268,11 @@ int snd_register_device(int type, struct snd_card *card, int dev, 
	snd_minors[minor] = preg;

	if (card)

		device = card->dev;

	class_device_create(sound_class, NULL, MKDEV(major, minor), device, "%s", name);

	preg->class_dev = class_device_create(sound_class, NULL,

					      MKDEV(major, minor),

					      device, "%s", name);

	if (preg->class_dev)

		class_set_devdata(preg->class_dev, private_data);



	mutex_unlock(&sound_mutex);

	return 0;
@@ -276,6 +280,24 @@ int snd_register_device(int type, struct snd_card *card, int dev, 


EXPORT_SYMBOL(snd_register_device);



/* find the matching minor record

 * return the index of snd_minor, or -1 if not found

 */

static int find_snd_minor(int type, struct snd_card *card, int dev)

{

	int cardnum, minor;

	struct snd_minor *mptr;



	cardnum = card ? card->number : -1;

	for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)

		if ((mptr = snd_minors[minor]) != NULL &&

		    mptr->type == type &&

		    mptr->card == cardnum &&

		    mptr->device == dev)

			return minor;

	return -1;

}



/**

 * snd_unregister_device - unregister the device on the given card

 * @type: the device type, SNDRV_DEVICE_TYPE_XXX
@@ -289,32 +311,42 @@ EXPORT_SYMBOL(snd_register_device); 
 */

int snd_unregister_device(int type, struct snd_card *card, int dev)

{

	int cardnum, minor;

	struct snd_minor *mptr;

	int minor;



	cardnum = card ? card->number : -1;

	mutex_lock(&sound_mutex);

	for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor)

		if ((mptr = snd_minors[minor]) != NULL &&

		    mptr->type == type &&

		    mptr->card == cardnum &&

		    mptr->device == dev)

			break;

	if (minor == ARRAY_SIZE(snd_minors)) {

	minor = find_snd_minor(type, card, dev);

	if (minor < 0) {

		mutex_unlock(&sound_mutex);

		return -EINVAL;

	}



	class_device_destroy(sound_class, MKDEV(major, minor));



	kfree(snd_minors[minor]);

	snd_minors[minor] = NULL;

	mutex_unlock(&sound_mutex);

	kfree(mptr);

	return 0;

}



EXPORT_SYMBOL(snd_unregister_device);



int snd_add_device_sysfs_file(int type, struct snd_card *card, int dev,

			      const struct class_device_attribute *attr)

{

	int minor, ret = -EINVAL;

	struct class_device *cdev;



	mutex_lock(&sound_mutex);

	minor = find_snd_minor(type, card, dev);

	if (minor >= 0 && (cdev = snd_minors[minor]->class_dev) != NULL)

		ret = class_device_create_file(cdev, attr);

	mutex_unlock(&sound_mutex);

	return ret;



}



EXPORT_SYMBOL(snd_add_device_sysfs_file);



#ifdef CONFIG_PROC_FS

/*

 *  INFO PART