With generic AC97 ASoC glue driver (codec/ac97.c), we get following warning when the device is registered (slightly stripped the backtrace):

kobject (c5a863e8): tried to init an initialized object, something is seriously wrong. [<c00254fc>] (unwind_backtrace+0x0/0xec) [<c014fad0>] (kobject_init+0x38/0x70) [<c0171e94>] (device_initialize+0x20/0x70) [<c017267c>] (device_register+0xc/0x18) [<bf20db70>] (snd_soc_instantiate_cards+0x924/0xacc [snd_soc_core]) [<bf20e0d0>] (snd_soc_register_platform+0x16c/0x198 [snd_soc_core]) [<c0175304>] (platform_drv_probe+0x18/0x1c) [<c0174454>] (driver_probe_device+0xb0/0x16c) [<c017456c>] (__driver_attach+0x5c/0x7c) [<c0173cec>] (bus_for_each_dev+0x48/0x78) [<c0173600>] (bus_add_driver+0x98/0x214) [<c0174834>] (driver_register+0xa4/0x130) [<c001f410>] (do_one_initcall+0xd0/0x1a4) [<c0062ddc>] (sys_init_module+0x12b0/0x1454)

This happens because the generic AC97 glue driver creates its codec->ac97 via calling snd_ac97_mixer(). snd_ac97_mixer() provides own version of snd_device.register which handles the device registration when snd_card_register() is called.

To avoid registering the AC97 device twice, we add a new flag to the snd_soc_codec: ac97_created which tells whether the AC97 device was created by SoC subsystem.

Signed-off-by: Mika Westerberg mika.westerberg@iki.fi --- I'm not sure whether this is the best solution to the issue. Maybe we could just check codec->ac97->dev.bus and refuse to register the device again?

include/sound/soc.h | 1 + sound/soc/soc-core.c | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/include/sound/soc.h b/include/sound/soc.h index 4fb079e..5c3bce8 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -442,6 +442,7 @@ struct snd_soc_codec { unsigned int suspended:1; /* Codec is in suspend PM state */ unsigned int probed:1; /* Codec has been probed */ unsigned int ac97_registered:1; /* Codec has been AC97 registered */ + unsigned int ac97_created:1; /* Codec has been created by SoC */ unsigned int sysfs_registered:1; /* codec has been sysfs registered */

/* codec IO */ diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 8751efd..7d22b5d 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -1497,6 +1497,16 @@ static int soc_register_ac97_dai_link(struct snd_soc_pcm_runtime *rtd) * for the generic AC97 subsystem. */ if (rtd->codec_dai->driver->ac97_control && !rtd->codec->ac97_registered) { + /* + * It is possible that the AC97 device is already registered to + * the device subsystem. This happens when the device is created + * via snd_ac97_mixer(). Currently only SoC codec that does so + * is the generic AC97 glue but others migh emerge. + * + * In those cases we don't try to register the device again. + */ + if (!rtd->codec->ac97_created) + return 0;

ret = soc_ac97_dev_register(rtd->codec); if (ret < 0) { @@ -1812,6 +1822,13 @@ int snd_soc_new_ac97_codec(struct snd_soc_codec *codec,

codec->ac97->bus->ops = ops; codec->ac97->num = num; + + /* + * Mark the AC97 device to be created by us. This way we ensure that the + * device will be registered with the device subsystem later on. + */ + codec->ac97_created = 1; + mutex_unlock(&codec->mutex); return 0; } @@ -1832,6 +1849,7 @@ void snd_soc_free_ac97_codec(struct snd_soc_codec *codec) kfree(codec->ac97->bus); kfree(codec->ac97); codec->ac97 = NULL; + codec->ac97_created = 0; mutex_unlock(&codec->mutex); } EXPORT_SYMBOL_GPL(snd_soc_free_ac97_codec);