ASoC: wm8995: Slightly optimize configure_clock

snd_soc_update_bits() will only write new register value
if the old value is different from the new value.
In additional, snd_soc_update_bits() returns 0 for no change.
No need to read WM8995_CLOCKING_1 register before calling snd_soc_update_bits().

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Axel Lin 2011-10-04 20:08:04 +08:00 committed by Mark Brown
parent 04f45c493a
commit 734787550a

View File

@ -485,7 +485,7 @@ static int configure_aif_clock(struct snd_soc_codec *codec, int aif)
static int configure_clock(struct snd_soc_codec *codec)
{
struct wm8995_priv *wm8995;
int old, new;
int change, new;
wm8995 = snd_soc_codec_get_drvdata(codec);
@ -509,15 +509,11 @@ static int configure_clock(struct snd_soc_codec *codec)
else
new = 0;
old = snd_soc_read(codec, WM8995_CLOCKING_1) & WM8995_SYSCLK_SRC;
/* If there's no change then we're done. */
if (old == new)
change = snd_soc_update_bits(codec, WM8995_CLOCKING_1,
WM8995_SYSCLK_SRC_MASK, new);
if (!change)
return 0;
snd_soc_update_bits(codec, WM8995_CLOCKING_1,
WM8995_SYSCLK_SRC_MASK, new);
snd_soc_dapm_sync(&codec->dapm);
return 0;