ASoC: wm8753: Skip noop reconfiguration of DAI mode

commit 2391a0e06789a3f1718dee30b282562f7ed28c87 upstream.

This patch makes it possible to set DAI mode to its currently applied
value even if codec is active. This is necessary to allow

aplay -t raw -r 44100 -f S16_LE -c 2 < /dev/urandom &
alsactl store -f backup.state
alsactl restore -f backup.state

to work without returning errors. This patch is based on a patch sent
by Klaus Kurzmann <mok@fluxnetz.de>.

Signed-off-by: Timo Juhani Lindfors <timo.lindfors@iki.fi>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/sound/soc/codecs/wm8753.c b/sound/soc/codecs/wm8753.c
index aa091a0d81873b9f09ceeb30bf7dcd46f6d05cd1..66d18a3e57f6f6b7dc07f6e469314131fffb2af1 100644 (file)
--- a/sound/soc/codecs/wm8753.c
+++ b/sound/soc/codecs/wm8753.c
@@ -189,6 +189,9 @@ static int wm8753_set_dai(struct snd_kcontrol *kcontrol,
        struct wm8753_priv *wm8753 = snd_soc_codec_get_drvdata(codec);
        u16 ioctl;
 
+       if (wm8753->dai_func == ucontrol->value.integer.value[0])
+               return 0;
+
        if (codec->active)
                return -EBUSY;