Re: [alsa-devel] [PATCH] ALSA: control: obsolete 'already present' messaging because it's caller's fault

At Sun, 8 Feb 2015 19:29:08 +0900, Takashi Sakamoto wrote:

When drivers or userspace applications add a duplicated control, snd module outputs error message and return -EBUSY.

This state is a bug in driver or application, therefore the messaging should be done by them, not by snd module.

The message should be hidden for user-space actions, indeed, but it's been very helpful for the driver developments, so I'm against the unconditional removal.

Also, think what you really suggested: there are almost 500 calls of snd_ctl_add() in the tree and you suggest to put the error message to each of them.

Rather try to show the error only for the kernel snd_ctl_add() calls.

thanks,

Takashi

Signed-off-by: Takashi Sakamoto o-takashi@sakamocchi.jp

sound/core/control.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/sound/core/control.c b/sound/core/control.c index d482997..8906b66 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -357,18 +357,10 @@ int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)

down_write(&card->controls_rwsem); if (snd_ctl_find_id(card, &id)) {

• up_write(&card->controls_rwsem);
  

• dev_err(card->dev, "control %i:%i:%i:%s:%i is already present\n",
  

• 			id.iface,
  

• 			id.device,
  

• 			id.subdevice,
  

• 			id.name,
  

• 			id.index);
  

  err = -EBUSY; goto error; } if (snd_ctl_find_hole(card, kcontrol->count) < 0) {

• up_write(&card->controls_rwsem);
  

  err = -ENOMEM; goto error; }

@@ -388,6 +380,7 @@ int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol) return 0;

error:

• up_write(&card->controls_rwsem); snd_ctl_free_one(kcontrol); return err;

}

2.1.0