Re: [PATCH] PM / Domains: Propagate start and restore errors during runtime resume

[Rafael J. Wysocki]

On Thu, Mar 3, 2016 at 9:32 PM, Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> On Thu, Mar 3, 2016 at 9:24 PM, Kevin Hilman <khilman@xxxxxxxxxxxx> wrote:
>> Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx> writes:
>>
>>> During runtime resume the return values of the start and restore steps
>>> are ignored. As a result drivers are not notified of runtime resume
>>> failures and can't propagate them up. Fix it by returning an error if
>>> either the start or restore step fails, and clean up properly in the
>>> error path.
>>>
>>> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
>>> ---
>>>  drivers/base/power/domain.c | 20 ++++++++++++++++++--
>>>  1 file changed, 18 insertions(+), 2 deletions(-)
>>>
>>> This fixes an issue I've noticed with my driver's .runtime_resume() handler
>>> returning an error that was never propagated out of pm_runtime_get_sync().
>>
>> Acked-by: Kevin Hilman <khilman@xxxxxxxxxxxx>
>>
>>> A second issue then appeared. The device .runtime_error field is set to the
>>> error code returned by my .runtime_resume() handler, but it never reset. Any
>>> subsequent try to resume the device fails with -EINVAL. I'm not sure what the
>>> right way to solve that is, advices are welcome.
>>
>> Probably setting it (back) to zero after each successful runtime_suspend
>> or runtime_resume is the right way.  Rafael?
>
> That follows the assumption that runtime PM usually won't be reliable
> after an error, so runtime_error has to be cleared explicitly via
> pm_runtime_set_status().

Sorry, that won't work.

Anyway, the idea is that the error has to be cleared manually after a failure.