Re: [PATCH v2 3/8] core: platform: wakeup the parent before trying any driver operations

From: Heikki Krogerus
Date: Tue May 26 2015 - 09:28:57 EST


On Mon, May 25, 2015 at 01:36:43PM -0400, Alan Stern wrote:
> On Mon, 25 May 2015, Andy Shevchenko wrote:
>
> > From: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> >
> > If the parent is still suspended when a driver probe,
> > remove or shutdown is attempted, the result may be a
> > failure.
> >
> > For example, if the parent is a PCI MFD device that has been
> > suspended when we try to probe our device, any register
> > reads will return 0xffffffff.
> >
> > To fix the problem, making sure the parent is always awake
> > before using driver probe, remove or shutdown.
> >
> > Signed-off-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> > ---
> > drivers/base/platform.c | 21 ++++++++++++++++++++-
>
> Why make the changes here rather than in dd.c? Is there something
> special about platform devices?

There isn't. That would definitely be better.


Thanks Alan,

--
heikki
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