Am Montag, 8. Juni 2009 13:29:26 schrieb Rafael J. Wysocki:
> But I need to be able to call __pm_schedule_resume() (at least) from
> interrupt context and I can't use a mutex from there. Otherwise I'd have
> used a mutex. :-)
I see.
> Anyway, below is a version with synchronous resume.
You are assuming autosuspend should always be with a delay. Why?
Secondly, you are not using a counter. Therefore only one driver can
control the PM state of a device at a given time. Is that wise?
> + * __pm_schedule_suspend - Schedule run-time suspend of given device.
> + * @dev: Device to suspend.
> + * @delay: Time to wait before attempting to suspend the device.
In which unit of time? If this is to go into kerneldoc that must be specified.
> + * @autocancel: If set, the request will be cancelled during a resume from
> a + * system-wide sleep state if it happens before @delay elapses.
Why is this needed?
> + */
> +void __pm_schedule_suspend(struct device *dev, unsigned long delay,
> + bool autocancel)
[..]
> +
> +/**
> + * __pm_schedule_resume - Schedule run-time resume of given device.
> + * @dev: Device to resume.
> + * @autocancel: If set, the request will be cancelled during a resume from
> a + * system-wide sleep state if it happens before pm_autoresume() can be
> run. + */
Eeek! This is a bad idea. You never want to a resume to be cancelled.
> +void __pm_schedule_resume(struct device *dev, bool autocancel)
[..]
> +int pm_resume_sync(struct device *dev)
> +{
> + int error = 0;
> +
> + pm_lock_device(dev);
> + if (dev->power.runtime_status == RPM_IDLE) {
> + /* ->autosuspend() hasn't started yet, no need to resume. */
> + pm_cancel_suspend(dev);
> + goto out;
> + }
> +
> + if (dev->power.runtime_status == RPM_SUSPENDING) {
> + /*
> + * The ->autosuspend() callback is being executed right now,
> + * wait for it to complete.
> + */
> + pm_unlock_device(dev);
> + cancel_delayed_work_sync(&dev->power.suspend_work);
That is the most glorious abuse of an API I've seen this year :-)
Regards
Oliver
--
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
