Before initiating IPC and/or bus transactions when loading the topology during a component probe, which happens on card registration/creation, make sure the device for the SOF driver is pm_runtime active.
The SOF probe is not necessarily followed by the component probe, such a timing assumption can be broken in driver bind/unbind tests. This can be artifially shown if the module for the machine driver is 'blacklisted' and the SOF device becomes pm_runtime_suspended before manually calling modprobe to register the card.
In an initial experiment, pm_resume_and_get() was called from soc-component.c, since the current ASoC component model is arguably missing dependencies between component status and device status. However this approach proved too invasive and breaks all existing HDMI playback solutions on Intel platforms.
While this will result in duplication of code, generating pm_runtime transitions only if strictly required for a given component makes more sense overall. This patch adds the pm_runtime resume transition for SOF only.
BugLink: https://github.com/thesofproject/linux/issues/3651 Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Reviewed-by: Bard Liao yung-chuan.liao@linux.intel.com Reviewed-by: Péter Ujfalusi peter.ujfalusi@linux.intel.com --- sound/soc/sof/pcm.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/sound/soc/sof/pcm.c b/sound/soc/sof/pcm.c index a76d0b5b2ad95..27504abc5385f 100644 --- a/sound/soc/sof/pcm.c +++ b/sound/soc/sof/pcm.c @@ -604,6 +604,14 @@ static int sof_pcm_probe(struct snd_soc_component *component) const char *tplg_filename; int ret;
+ /* + * make sure the device is pm_runtime_active before loading the + * topology and initiating IPC or bus transactions + */ + ret = pm_runtime_resume_and_get(component->dev); + if (ret < 0 && ret != -EACCES) + return ret; + /* load the default topology */ sdev->component = component;
@@ -621,6 +629,9 @@ static int sof_pcm_probe(struct snd_soc_component *component) return ret; }
+ pm_runtime_mark_last_busy(component->dev); + pm_runtime_put_autosuspend(component->dev); + return ret; }