Re: [PATCH v4 1/6] hid: new driver for PicoLCD device

Jiri Kosina
2010-03-30T08:12:18Z

On Mon, 29 Mar 2010, Bruno Prémont wrote:

> > > +static struct hid_driver picolcd_driver = {
> > > + .name = "hid-picolcd",
> > > + .id_table = picolcd_devices,
> > > + .probe = picolcd_probe,
> > > + .remove = picolcd_remove,
> > > + .raw_event = picolcd_raw_event,
> > > +#ifdef CONFIG_PM
> > > + .suspend = picolcd_suspend,
> > > + .resume = picolcd_resume,
> > > + .reset_resume = picolcd_reset_resume,
> > > +#endif
> > > +};
> >
> > struct hid_driver doesn't provide power-management related callbacks.
> > So I guess that you have either not tested this feature at all, or
> > you have some extra patch somewhere which adds such callbacks to HID
> > core, but you haven't sent it out for review?
> >
> > In any cases, this will very likely cause compilation failure with
> > CONFIG_PM turned on.
>
> That's the patch I referred to (under series introduction mail) when
> saying:
> > The series depends on my previous patch adding HID suspend support
> > (I've not yet looked at improving it).
>
> Link to the patch:
> http://lkml.org/lkml/2010/2/24/233
>
> Especially the reset-resume part is important as the device has to be
> reprogrammed with framebuffer content, brightness/contrast in that case.
>
> As stated, Oliver didn't like the implementation of the addition of
> those hooks too much and I have yet to look at improving it.

Ah, OK, I have missed that one, thanks for pointing it out.

The driver itself now looks fine to me and I am willing to merge it,
modulo the power-management code -- so please either remove the parts that
depend on power management for now, or I'll wait on your respin of the
generic HID-PM patch.

Thanks,

--
Jiri Kosina
SUSE Labs, Novell Inc.