[PATCH v3 6/8] PM / ACPI: Enable the runtime PM centric approach for system sleep

Rafael J. Wysocki rjw at rjwysocki.net
Tue Aug 29 08:27:55 PDT 2017


On Tuesday, August 29, 2017 4:56:48 PM CEST Ulf Hansson wrote:
> This change enables the ACPI PM domain to cope with drivers that deploys
> the runtime PM centric path for system sleep.

[cut]

> @@ -1052,11 +1066,20 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete);
>   * @dev: Device to handle.
>   *
>   * Follow PCI and resume devices suspended at run time before running their
> - * system suspend callbacks.
> + * system suspend callbacks. However, try to avoid it in case the runtime PM
> + * centric path is used for the device and then trust the driver to do the
> + * right thing.
>   */
>  int acpi_subsys_suspend(struct device *dev)
>  {
> -	pm_runtime_resume(dev);
> +	struct acpi_device *adev = ACPI_COMPANION(dev);
> +
> +	if (!adev)
> +		return 0;
> +
> +	if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev))
> +		pm_runtime_resume(dev);
> +
>  	return pm_generic_suspend(dev);
>  }
>  EXPORT_SYMBOL_GPL(acpi_subsys_suspend);

Well, I tried to avoid calling acpi_dev_needs_resume() for multiple times
and that's why I added the update_state thing.

Moreover, the is_rpm_sleep flag here has to mean not only that
direct_complete should not be used with the device, but also that its driver
is fine with not resuming it.

IMO it is not a good idea to use one flag for these two different things at the
same time at all.

Thanks,
Rafael




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