Re: [Bug 10030] Suspend doesn't work when SD card is inserted

Alan Stern
2008-02-20T22:24:26Z

On Wed, 20 Feb 2008, Rafael J. Wysocki wrote:

> Well, below is an uncompiled and untested but illustrating the idea that
> might allow people not to bother with device_pm_schedule_removal()
> explicitly and can fix the issue at hand.
>
> [There are some cases that need handling and are not covered here.]
>
> Please have a look.
>
> Thanks,
> Rafael

> +static struct task_struct *suspending_task;
> +static DEFINE_MUTEX(suspending_task_mtx);

I suspect you don't really need this mutex.

> +bool in_suspend_context(void)
> +{
> + bool result;
> +
> + mutex_lock(&suspending_task_mtx);
> + result = (suspending_task == current);
> + mutex_unlock(&suspending_task_mtx);
> + return result;
> +}

If suspending_task == current then you are guaranteed to be serialized,
because everything a single task does is serial.

> @@ -1162,7 +1162,10 @@ void device_destroy(struct class *class,
> dev = class_find_device(class, &devt, __match_devt);
> if (dev) {
> put_device(dev);
> - device_unregister(dev);
> + if (in_suspend_context())
> + device_pm_schedule_removal(dev);
> + else
> + device_unregister(dev);
> }
> }

But what about device_del()? Can a similar change be made there?

Alan Stern