On Fri, Nov 22, 2013 at 7:50 AM, Rafael J. Wysocki
<rafael.j.wysocki@xxxxxxxxx> wrote:
> On 11/22/2013 10:08 AM, Dan Williams wrote:
>>
>> usbcore blocks powering off hub ports while a downstream source is
>> wakeup enabled. Once wakeup is disabled usbcore can try again to turn
>> off the parent port. Add a pm_runtime reference manipulation to retry a
>> port power down on disable, or pin the port active on enable.
>>
>> Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
>
>
> Well, while this generally won't hurt, I'm not sure how it helps either,
> because device_(disable|enable)_wakeup() don't touch any hardware and (for
> now) they are only about wakeup from system suspend.
>
If a USB device's parent port is turned off prior to system suspend
then remote wakeup will be blocked. We could handle this internally
by correcting the setting at suspend time, but would need to wake the
port and possibly recover the connection to suspend. Just seemed
cleaner to notify the setting change.
> I have a plan to change that, but for now it's just about system wakeup.
>
>
>> ---
>> drivers/base/power/wakeup.c | 9 ++++++++-
>> 1 files changed, 8 insertions(+), 1 deletions(-)
>>
>> diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
>> index 2d56f4113ae7..f784804137e7 100644
>> --- a/drivers/base/power/wakeup.c
>> +++ b/drivers/base/power/wakeup.c
>> @@ -14,6 +14,7 @@
>> #include <linux/suspend.h>
>> #include <linux/seq_file.h>
>> #include <linux/debugfs.h>
>> +#include <linux/pm_runtime.h>
>> #include <trace/events/power.h>
>> #include "power.h"
>> @@ -335,10 +336,16 @@ EXPORT_SYMBOL_GPL(device_init_wakeup);
>> */
>> int device_set_wakeup_enable(struct device *dev, bool enable)
>> {
>> + int rc;
>> +
>> if (!dev || !dev->power.can_wakeup)
>> return -EINVAL;
>> - return enable ? device_wakeup_enable(dev) :
>> device_wakeup_disable(dev);
>> + pm_runtime_get_sync(dev);
>> + rc = enable ? device_wakeup_enable(dev) :
>> device_wakeup_disable(dev);
>> + pm_runtime_put_sync(dev);
>
>
> And you can use pm_runtime_put() here to make the function return earlier.
>
>
Will do.
Thanks Rafael.
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