[PATCH 1/1] ARM: kirkwood: Add support for RaidSonic

[Andrew Lunn]

On Tue, May 01, 2012 at 07:34:29PM +0100, Jamie Lentin wrote:
> On Tue, 1 May 2012, Andrew Lunn wrote:
> 
> >Hi Simon
> >
> >The patch looks good.
> >
> >+static void ib62x0_power_off(void)
> >+{
> >+       gpio_set_value(IB62X0_GPIO_POWER_OFF, 1);
> >+}
> >
> >Seeing this set of a train of thought. I have a feature creep
> >request. Nice to have, i.e. not required to acceptance. This patterns
> >of using a GPIO line to turn the hardware off is seen quite a few
> >times. e.g.
> >
> >mach-kirkwood/netspace_v2-setup.c
> >mach-orion5x/mv2120-setup.c
> >mach-kirkwood/d2net_v2-setup.c
> >mach-kirkwood/netspace_v2-setup.c
> >
> >and a few more.
> >
> >How about writing a gpio-poweroff platform driver? It would take a
> >platform_data structure which lists which GPIO line to use, and if it
> >should be active high/low. The probe function would take control of
> >the GPIO line, set it to inactive state, and output. It would also
> >register a function for pm_power_off(). When that function is called,
> >it toggles the GPIO to turn the power off.
> >
> >Then wrap all this up in a DT binding.
> 
> I've been thinking about this too, would make a lot of sense. Most
> of the gpio-poweroff driver would be easy, although registering the
> power_off function wasn't immediately obvious.

pm_power_off is a global variable. You should be able to assign it
from anywhere.

     Andrew