[PATCH v2] ASoC: pxa2xx-ac97: fix oops when codec_driver probe runs
Mike Dunn
mikedunn at newsguy.com
Thu Jan 3 09:40:39 EST 2013
Change log:
v2: pxa2xx_ac97_hw_probe() is called *before* snd_soc_register_dais(), and
likewise pxa2xx_ac97_hw_remove() is called after snd_soc_unregister_dais().
Thanks much Mark.
This patch fixes a kernel oops that occurs when the snd_soc_codec_driver probe
function runs. The exception occurs when the codec calls soc_ac97_ops.reset().
The pxa2xx-ac97's clocks have not been initialized at this point, but the cpu's
reset function (pxa_ac97_cold_pxa27x()) expects them to be, resulting in a NULL
pointer dereference in the pxa's clk_enable().
The pxa2xx-ac97's clocks are initialized in pxa2xx_ac97_hw_probe(). To ensure
that the clocks are initialized when the codec_driver probe runs, the calls to
pxa2xx_ac97_hw_{probe,remove}() are moved from the cpu's dai_driver probe/remove
functions to those of its platform_driver. This is necessary because
snd_soc_instantiate_card() always calls the codec_driver probe before any of the
dai_drivers' probes.
This change leaves nothing in the cpu's dai_driver probe/remove functions, so
those functions are eliminated.
Tested on the pxa27x; palmtreo680 machine using the wm9712 codec.
Signed-off-by: Mike Dunn <mikedunn at newsguy.com>
---
sound/soc/pxa/pxa2xx-ac97.c | 27 ++++++++++-----------------
1 files changed, 10 insertions(+), 17 deletions(-)
diff --git a/sound/soc/pxa/pxa2xx-ac97.c b/sound/soc/pxa/pxa2xx-ac97.c
index 4b0a009..ba04f49 100644
--- a/sound/soc/pxa/pxa2xx-ac97.c
+++ b/sound/soc/pxa/pxa2xx-ac97.c
@@ -104,17 +104,6 @@ static int pxa2xx_ac97_resume(struct snd_soc_dai *dai)
#define pxa2xx_ac97_resume NULL
#endif
-static int pxa2xx_ac97_probe(struct snd_soc_dai *dai)
-{
- return pxa2xx_ac97_hw_probe(to_platform_device(dai->dev));
-}
-
-static int pxa2xx_ac97_remove(struct snd_soc_dai *dai)
-{
- pxa2xx_ac97_hw_remove(to_platform_device(dai->dev));
- return 0;
-}
-
static int pxa2xx_ac97_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *cpu_dai)
@@ -184,8 +173,6 @@ static struct snd_soc_dai_driver pxa_ac97_dai_driver[] = {
{
.name = "pxa2xx-ac97",
.ac97_control = 1,
- .probe = pxa2xx_ac97_probe,
- .remove = pxa2xx_ac97_remove,
.suspend = pxa2xx_ac97_suspend,
.resume = pxa2xx_ac97_resume,
.playback = {
@@ -236,15 +223,20 @@ EXPORT_SYMBOL_GPL(soc_ac97_ops);
static int pxa2xx_ac97_dev_probe(struct platform_device *pdev)
{
+ int ret;
+
if (pdev->id != -1) {
dev_err(&pdev->dev, "PXA2xx has only one AC97 port.\n");
return -ENXIO;
}
- /* Punt most of the init to the SoC probe; we may need the machine
- * driver to do interesting things with the clocking to get us up
- * and running.
- */
+ ret = pxa2xx_ac97_hw_probe(pdev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "pxa2xx_ac97_hw_probe failed with %d\n",
+ ret);
+ return ret;
+ }
+
return snd_soc_register_dais(&pdev->dev, pxa_ac97_dai_driver,
ARRAY_SIZE(pxa_ac97_dai_driver));
}
@@ -252,6 +244,7 @@ static int pxa2xx_ac97_dev_probe(struct platform_device *pdev)
static int pxa2xx_ac97_dev_remove(struct platform_device *pdev)
{
snd_soc_unregister_dais(&pdev->dev, ARRAY_SIZE(pxa_ac97_dai_driver));
+ pxa2xx_ac97_hw_remove(pdev);
return 0;
}
--
1.7.8.6
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