freebsd-dev/sys/dev/gpio/gpiopower.c
Justin Hibbits 099a0e1bea Add a GPIO poweroff and reset driver.
Summary:
This implements part of the gpio-poweroff and gpio-restart device tree
bindings.  Optional properties are not handled currently.  It also currently
only supports level-triggered reset.

Reviewed By: gonzo
Differential Revision: https://reviews.freebsd.org/D8521
2016-11-16 02:14:07 +00:00

138 lines
3.5 KiB
C

/*-
* Copyright (c) 2016 Justin Hibbits
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/eventhandler.h>
#include <sys/gpio.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/reboot.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/gpio/gpiobusvar.h>
struct gpiopower_softc {
gpio_pin_t sc_pin;
int sc_rbmask;
};
static void gpiopower_assert(device_t dev, int howto);
static int
gpiopower_probe(device_t dev)
{
if (ofw_bus_is_compatible(dev, "gpio-poweroff")) {
device_set_desc(dev, "GPIO poweroff control");
return (0);
} else if (ofw_bus_is_compatible(dev, "gpio-restart")) {
device_set_desc(dev, "GPIO restart control");
return (0);
}
return (ENXIO);
}
static int
gpiopower_attach(device_t dev)
{
struct gpiopower_softc *sc;
phandle_t node;
sc = device_get_softc(dev);
if ((node = ofw_bus_get_node(dev)) == -1)
return (ENXIO);
ofw_gpiobus_parse_gpios(dev, "gpios", &sc->sc_pin);
if (sc->sc_pin == NULL) {
device_printf(dev, "failed to map GPIO pin\n");
return (ENXIO);
}
if (ofw_bus_is_compatible(dev, "gpio-poweroff"))
sc->sc_rbmask = RB_HALT | RB_POWEROFF;
else
sc->sc_rbmask = 0;
EVENTHANDLER_REGISTER(shutdown_final, gpiopower_assert, dev,
SHUTDOWN_PRI_LAST);
gpio_pin_setflags(sc->sc_pin, GPIO_PIN_OUTPUT);
return (0);
}
static void
gpiopower_assert(device_t dev, int howto)
{
struct gpiopower_softc *sc;
int do_assert;
sc = device_get_softc(dev);
do_assert = sc->sc_rbmask ? (sc->sc_rbmask & howto) :
((howto & RB_HALT) == 0);
if (!do_assert)
return;
if (howto & RB_POWEROFF)
device_printf(dev, "powering system off\n");
else if ((howto & RB_HALT) == 0)
device_printf(dev, "resetting system\n");
else
return;
gpio_pin_set_active(sc->sc_pin, true);
/* Wait a second for it to trip */
DELAY(10000000);
}
static devclass_t gpiopower_devclass;
static device_method_t gpiopower_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, gpiopower_probe),
DEVMETHOD(device_attach, gpiopower_attach),
DEVMETHOD_END
};
static driver_t gpiopower_driver = {
"gpiopower",
gpiopower_methods,
sizeof(struct gpiopower_softc)
};
DRIVER_MODULE(gpiopower, simplebus, gpiopower_driver, gpiopower_devclass, 0, 0);
MODULE_DEPEND(gpiopower, gpiobus, 1, 1, 1);