ALSA: core: Allow card id change to the same string

When user want to change the card id to the same string
on the card via /sys/class/sound/cardX/id, do not
report error. Instead return with success without
doing anything.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/init.c b/sound/core/init.c
index ec4a50c..2de45fb 100644 (file)
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -607,11 +607,16 @@ card_id_store_attr(struct device *dev, struct device_attribute *attr,
                return -EEXIST;
        }
        for (idx = 0; idx < snd_ecards_limit; idx++) {
-               if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1))
-                       goto __exist;
+               if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1)) {
+                       if (card == snd_cards[idx])
+                               goto __ok;
+                       else
+                               goto __exist;
+               }
        }
        strcpy(card->id, buf1);
        snd_info_card_id_change(card);
+__ok:
        mutex_unlock(&snd_card_mutex);
 
        return count;