ASoC: STA32x: Preserve reserved register bits

Chip documentation explicitly requires that the reset values
of reserved register bits are left untouched.  It is possible
there are differences between STA326 and STA328 or future
chip revisions in these bits, and clobbering them might
cause malfunction.

Signed-off-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Johannes Stezenbach 2011-07-11 17:01:24 +02:00 committed by Mark Brown
parent 7968843915
commit 889ebae537

View File

@ -756,6 +756,22 @@ static int sta32x_probe(struct snd_soc_codec *codec)
for (i = 0; i < STA32X_REGISTER_COUNT; i++)
snd_soc_cache_write(codec, i, sta32x_regs[i]);
/* preserve reset values of reserved register bits */
snd_soc_cache_write(codec, STA32X_CONFC,
codec->hw_read(codec, STA32X_CONFC));
snd_soc_cache_write(codec, STA32X_CONFE,
codec->hw_read(codec, STA32X_CONFE));
snd_soc_cache_write(codec, STA32X_CONFF,
codec->hw_read(codec, STA32X_CONFF));
snd_soc_cache_write(codec, STA32X_MMUTE,
codec->hw_read(codec, STA32X_MMUTE));
snd_soc_cache_write(codec, STA32X_AUTO1,
codec->hw_read(codec, STA32X_AUTO1));
snd_soc_cache_write(codec, STA32X_AUTO3,
codec->hw_read(codec, STA32X_AUTO3));
snd_soc_cache_write(codec, STA32X_C3CFG,
codec->hw_read(codec, STA32X_C3CFG));
/* FIXME enable thermal warning adjustment and recovery */
snd_soc_update_bits(codec, STA32X_CONFA,
STA32X_CONFA_TWAB | STA32X_CONFA_TWRB, 0);