Commit ae07eb9b authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: vmaster: Add snd_ctl_add_followers() helper 

Add a new helper to add multiple vmaster followers in a shot.  The
same function was open-coded in various places, and this helper
replaces them.

Link: https://lore.kernel.org/r/20230721071643.3631-2-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent ebc1bfeb

include/sound/control.h

+3 −0
Original line number Diff line number Diff line
@@ -262,6 +262,9 @@ snd_ctl_add_follower(struct snd_kcontrol *master, struct snd_kcontrol *follower) 
	return _snd_ctl_add_follower(master, follower, 0);

}



int snd_ctl_add_followers(struct snd_card *card, struct snd_kcontrol *master,

			  const char * const *list);



/**

 * snd_ctl_add_follower_uncached - Add a virtual follower control

 * @master: vmaster element

sound/core/vmaster.c

+28 −0
Original line number Diff line number Diff line
@@ -280,6 +280,34 @@ int _snd_ctl_add_follower(struct snd_kcontrol *master, 
}

EXPORT_SYMBOL(_snd_ctl_add_follower);



/**

 * snd_ctl_add_followers - add multiple followers to vmaster

 * @card: card instance

 * @master: the target vmaster kcontrol object

 * @list: NULL-terminated list of name strings of followers to be added

 *

 * Adds the multiple follower kcontrols with the given names.

 * Returns 0 for success or a negative error code.

 */

int snd_ctl_add_followers(struct snd_card *card, struct snd_kcontrol *master,

			  const char * const *list)

{

	struct snd_kcontrol *follower;

	int err;



	for (; *list; list++) {

		follower = snd_ctl_find_id_mixer(card, *list);

		if (follower) {

			err = snd_ctl_add_follower(master, follower);

			if (err < 0)

				return err;

		}

	}



	return 0;

}

EXPORT_SYMBOL_GPL(snd_ctl_add_followers);



/*

 * ctl callbacks for master controls

 */