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@newsguy.com ---
I'm new to the ASoC code. Experts, please have a look. Thanks!
sound/soc/pxa/pxa2xx-ac97.c | 38 +++++++++++++++++++------------------- 1 files changed, 19 insertions(+), 19 deletions(-)
diff --git a/sound/soc/pxa/pxa2xx-ac97.c b/sound/soc/pxa/pxa2xx-ac97.c index 4b0a009..940e9f4 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 = { @@ -236,21 +223,34 @@ 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. - */ - return snd_soc_register_dais(&pdev->dev, pxa_ac97_dai_driver, - ARRAY_SIZE(pxa_ac97_dai_driver)); + ret = snd_soc_register_dais(&pdev->dev, pxa_ac97_dai_driver, + ARRAY_SIZE(pxa_ac97_dai_driver)); + if (ret < 0) { + dev_err(&pdev->dev, "snd_soc_register_dais failed with %d\n", + ret); + return ret; + } + + ret = pxa2xx_ac97_hw_probe(pdev); + if (ret < 0) { + dev_err(&pdev->dev, "pxa2xx_ac97_hw_probe failed with %d\n", + ret); + snd_soc_unregister_dais(&pdev->dev, + ARRAY_SIZE(pxa_ac97_dai_driver)); + } + return ret; }
static int pxa2xx_ac97_dev_remove(struct platform_device *pdev) { + pxa2xx_ac97_hw_remove(pdev); snd_soc_unregister_dais(&pdev->dev, ARRAY_SIZE(pxa_ac97_dai_driver)); return 0; }