Re: [PATCH 3/3] Input: add generic gpio brownout driver

[Marco Felsch <m.felsch@xxxxxxxxxxxxxx>]

Hi Trent,

On 18-10-01 16:35, Trent Piepho wrote:
> On Mon, 2018-10-01 at 09:19 +0200, Marco Felsch wrote:
> > On 18-09-28 17:19, Dmitry Torokhov wrote:
> > > 
> > > > 
> > > > This patch adds the support for a generic gpio-based brownout
> > > > detection. Upon a brownout the host system gets informed and the driver
> > > > sends a keycode signal to the userspace. Per default this signal is
> > > > mapped to KEY_POWER, so the system will shoutdown.
> > > 
> > > I do not believe this functionality should be exposed as an input
> > > device, as it has nothing to do with human interaction with the
> > > computing device. To me this is akin over-current on a USB port, or
> > > carrier signal on network interfaces.
> > 
> > I'm still uncertain putting the code into the input framework. I tought
> > a lot about the correct place. For me it's like a button, which is
> > 'pressed' by the hardware. Yes, it's a bit abstract..
> 
> For quite a few years, the hwmon subsystem has had devices that will
> generate an interrupt on low voltage (or high voltage, or high
> temperature ...) and drivers that export that interrupt to userspace.
> 
> This device doesn't seem any different that a somewhat limited hwmon
> device with just an "in0_alarm" attribute.

Thanks for the feedback and the idea. I will migrate the driver to the
hwmon subsystem.

Regards,
Marco