Commit 6d212d8e authored Oct 29, 2010 by Mark Brown

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

parent c593b520

sound/soc/codecs/wm8900.c

+0 −6

Original line number	Diff line number	Diff line
		@@ -186,7 +186,6 @@ static int wm8900_volatile_register(unsigned int reg)
		{
		switch (reg) {
		case WM8900_REG_ID:
		case WM8900_REG_POWER1:
		return 1;
		default:
		return 0;
		@@ -1200,11 +1199,6 @@ static int wm8900_probe(struct snd_soc_codec *codec)
		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 */