[alsa-devel] [PATCH 3/9] ASoC: codecs: wm8523: Fix register cache incoherency

Lars-Peter Clausen lars at metafoo.de
Tue Dec 28 21:37:57 CET 2010


The multi-component patch(commit f0fba2ad1) moved the allocation of the
register cache from the driver to the ASoC core. Most drivers where adjusted to
this, but the wm8523 driver still uses its own register cache for its
private functions, while functions from the ASoC core use the generic cache.
Thus we end up with two from each other incoherent caches, which can lead to
undefined behaviour.
This patch fixes the issue by changing the wm8523 driver to use the
generic register cache in its private functions.

Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
Cc: Ian Lartey <ian at opensource.wolfsonmicro.com>
Cc: Dimitris Papastamos <dp at opensource.wolfsonmicro.com>

---
Compile tested only
---
 sound/soc/codecs/wm8523.c |    9 +++++----
 1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/sound/soc/codecs/wm8523.c b/sound/soc/codecs/wm8523.c
index 9a433a5..deca79e 100644
--- a/sound/soc/codecs/wm8523.c
+++ b/sound/soc/codecs/wm8523.c
@@ -41,7 +41,6 @@ static const char *wm8523_supply_names[WM8523_NUM_SUPPLIES] = {
 /* codec private data */
 struct wm8523_priv {
 	enum snd_soc_control_type control_type;
-	u16 reg_cache[WM8523_REGISTER_COUNT];
 	struct regulator_bulk_data supplies[WM8523_NUM_SUPPLIES];
 	unsigned int sysclk;
 	unsigned int rate_constraint_list[WM8523_NUM_RATES];
@@ -314,6 +313,7 @@ static int wm8523_set_bias_level(struct snd_soc_codec *codec,
 				 enum snd_soc_bias_level level)
 {
 	struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
+	u16 *reg_cache = codec->reg_cache;
 	int ret, i;
 
 	switch (level) {
@@ -344,7 +344,7 @@ static int wm8523_set_bias_level(struct snd_soc_codec *codec,
 			/* Sync back default/cached values */
 			for (i = WM8523_AIF_CTRL1;
 			     i < WM8523_MAX_REGISTER; i++)
-				snd_soc_write(codec, i, wm8523->reg_cache[i]);
+				snd_soc_write(codec, i, reg_cache[i]);
 
 
 			msleep(100);
@@ -414,6 +414,7 @@ static int wm8523_resume(struct snd_soc_codec *codec)
 static int wm8523_probe(struct snd_soc_codec *codec)
 {
 	struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
+	u16 *reg_cache = codec->reg_cache;
 	int ret, i;
 
 	codec->hw_write = (hw_write_t)i2c_master_send;
@@ -470,8 +471,8 @@ static int wm8523_probe(struct snd_soc_codec *codec)
 	}
 
 	/* Change some default settings - latch VU and enable ZC */
-	wm8523->reg_cache[WM8523_DAC_GAINR] |= WM8523_DACR_VU;
-	wm8523->reg_cache[WM8523_DAC_CTRL3] |= WM8523_ZC;
+	reg_cache[WM8523_DAC_GAINR] |= WM8523_DACR_VU;
+	reg_cache[WM8523_DAC_CTRL3] |= WM8523_ZC;
 
 	wm8523_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
 
-- 
1.7.2.3



More information about the Alsa-devel mailing list