In sof-of-dev.c static void sof_of_probe_complete(struct device *dev) { /* allow runtime_pm */ pm_runtime_set_autosuspend_delay(dev, SND_SOF_SUSPEND_DELAY_MS); pm_runtime_use_autosuspend(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev);
pm_runtime_mark_last_busy(dev); pm_runtime_put_autosuspend(dev);
this last line looks wrong
it looks like the code in sof-of-dev.c is imbalanced. The last pm_runtime_put_autosuspend() is not matching any pm_runtime_get_sync(), is it?
}
After pm_runtime_put_autosuspend, the current device power usage count should minus one. (1->0)
And wait SND_SOF_SUSPEND_DELAY_MS seconds, sof device will autosuspend (because the power usage count is 0 ).
Indeed.
We have this comment for the PCI case:
/* follow recommendation in pci-driver.c to decrement usage counter */ pm_runtime_put_noidle(dev);
and a matching one for remove: /* follow recommendation in pci-driver.c to increment usage counter */ if (snd_sof_device_probe_completed(&pci->dev) && !(sof_pci_debug & SOF_PCI_DISABLE_PM_RUNTIME)) pm_runtime_get_noresume(&pci->dev);
In the general case, I don't know why you would need to add a put_autosuspend in the probe complete, even for cases where the device does support pm_runtime.
Having a mark_last_busy() is fine though, it would reset the counters and let the autosuspend happen at a later time. But I would call this before enable for consistency.
Can you try with the sequence below in probe_complete?
pm_runtime_set_autosuspend_delay(dev, DELAY_MS); pm_runtime_use_autosuspend(dev); pm_runtime_mark_last_busy(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev);