Re: [PATCH 1/3] PM / Runtime: Fix rpm_resume() return value forpower.no_callbacks set

From: Alan Stern
Date: Wed Aug 15 2012 - 12:14:46 EST


On Tue, 14 Aug 2012, Rafael J. Wysocki wrote:

>
> For devices whose power.no_callbacks flag is set, rpm_resume()
> should return 1 if the device's parent is already active, so that
> the callers of pm_runtime_get() don't think that they have to wait
> for the device to resume (asynchronously) in that case (the core
> won't queue up an asynchronous resume in that case, so there's
> nothing to wait for anyway).
>
> Modify the code accordingly (and make sure that an idle notification
> will be queued up on success, even if 1 is to be returned).
>
> Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
> ---
> drivers/base/power/runtime.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> Index: linux/drivers/base/power/runtime.c
> ===================================================================
> --- linux.orig/drivers/base/power/runtime.c
> +++ linux/drivers/base/power/runtime.c
> @@ -584,6 +584,7 @@ static int rpm_resume(struct device *dev
> || dev->parent->power.runtime_status == RPM_ACTIVE) {
> atomic_inc(&dev->parent->power.child_count);
> spin_unlock(&dev->parent->power.lock);
> + retval = 1;
> goto no_callback; /* Assume success. */
> }
> spin_unlock(&dev->parent->power.lock);
> @@ -664,7 +665,7 @@ static int rpm_resume(struct device *dev
> }
> wake_up_all(&dev->power.wait_queue);
>
> - if (!retval)
> + if (retval >= 0)
> rpm_idle(dev, RPM_ASYNC);
>
> out:

Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/