Re: kernel panic on gpio-keys

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Mon, Dec 30, 2013 at 04:13:12PM +0100, Paul Cercueil wrote:
> On 27/12/2013 02:56, Dmitry Torokhov wrote:
> >On Tue, Dec 17, 2013 at 04:17:34PM +0100, Paul Cercueil wrote:
> >>On 14/12/2013 10:39, Dmitry Torokhov wrote:
> >>>On Wed, Dec 11, 2013 at 08:17:29PM +0100, Paul Cercueil wrote:
> >>>>Hi there,
> >>>>
> >>>>I am trying to use the gpio-keys driver to inject joystick events.
> >>>>There seems to be some basic support of it, looking at <linux/gpio_keys.h>.
> >>>>
> >>>>However, registering the following will trigger a kernel panic in
> >>>>the kernel:
> >>>>
> >>>>static struct gpio_keys_button my_buttons[] {
> >>>>	{
> >>>>		.gpio = GPIO_FOO,
> >>>>		.type = EV_ABS,
> >>>>		.code = ABS_HAT0X,
> >>>>		.value = 1,
> >>>>	},
> >>>>};
> >>>>
> >>>>(tested on kernel 3.12).
> >>>>
> >>>>I don't know well the input subsystem, so I have no idea of what is
> >>>>going wrong. Could anybody try to at least reproduce the issue?
> >>>
> >>>It woudl be helpful if you poster the stack trace from panic so we'd
> >>>have an idea where the fault happens.
> >>>
> >>>Thanks.
> >>>
> >>
> >>Here is the crash log I get: http://pastebin.com/FzTTGxsR
> >>(I did put it on pastebin because it's huge, 200+ lines).
> >>
> >>The first OOPS happen as soon as the GPIO button is pressed; the
> >>other ones seem to happen recursively. I included only a part of the
> >>log I get, as the OOPSes continue to flow until the watchdog kicks
> >>in.
> >
> >Hmm, I have an idea: this driver is one of few that does not use
> >input_set_abs_info() and this does not allocate memory for absinfo data
> >that input core uses to handle absolute events.
> >
> >Does the patch below work for you?
> >
> >Thanks.
> >
> 
> Hi,
> 
> The patch works just fine, thank you!

Thanks Paul.

-- 
Dmitry