ASoC: Remove volatility from WM8900 POWER1 register
Not all bits can be read back from POWER1 so avoid corruption when using
a read/modify/write cycle by marking it non-volatile - the only thing we
read back from it is the chip revision which has diagnostic value only.
We can re-add later but that's a more invasive change than is suitable
for a bugfix.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: stable@kernel.org
diff --git a/sound/soc/codecs/wm8900.c b/sound/soc/codecs/wm8900.c
index b4f1172..aca4b1e 100644
--- a/sound/soc/codecs/wm8900.c
+++ b/sound/soc/codecs/wm8900.c
@@ -186,7 +186,6 @@
{
switch (reg) {
case WM8900_REG_ID:
- case WM8900_REG_POWER1:
return 1;
default:
return 0;
@@ -1200,11 +1199,6 @@
return -ENODEV;
}
- /* Read back from the chip */
- reg = snd_soc_read(codec, WM8900_REG_POWER1);
- reg = (reg >> 12) & 0xf;
- dev_info(codec->dev, "WM8900 revision %d\n", reg);
-
wm8900_reset(codec);
/* Turn the chip on */