reset.c
1.92 KB
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/*
* Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2009 PetaLogix
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/of_platform.h>
#include <asm/prom.h>
/* Trigger specific functions */
#ifdef CONFIG_GPIOLIB
#include <linux/of_gpio.h>
static int handle; /* reset pin handle */
static unsigned int reset_val;
void of_platform_reset_gpio_probe(void)
{
int ret;
handle = of_get_named_gpio(of_find_node_by_path("/"),
"hard-reset-gpios", 0);
if (!gpio_is_valid(handle)) {
printk(KERN_INFO "Skipping unavailable RESET gpio %d (%s)\n",
handle, "reset");
}
ret = gpio_request(handle, "reset");
if (ret < 0) {
printk(KERN_INFO "GPIO pin is already allocated\n");
return;
}
/* get current setup value */
reset_val = gpio_get_value(handle);
/* FIXME maybe worth to perform any action */
pr_debug("Reset: Gpio output state: 0x%x\n", reset_val);
/* Setup GPIO as output */
ret = gpio_direction_output(handle, 0);
if (ret < 0)
goto err;
/* Setup output direction */
gpio_set_value(handle, 0);
printk(KERN_INFO "RESET: Registered gpio device: %d, current val: %d\n",
handle, reset_val);
return;
err:
gpio_free(handle);
return;
}
static void gpio_system_reset(void)
{
gpio_set_value(handle, 1 - reset_val);
}
#else
#define gpio_system_reset() do {} while (0)
void of_platform_reset_gpio_probe(void)
{
return;
}
#endif
void machine_restart(char *cmd)
{
printk(KERN_NOTICE "Machine restart...\n");
gpio_system_reset();
dump_stack();
while (1)
;
}
void machine_shutdown(void)
{
printk(KERN_NOTICE "Machine shutdown...\n");
while (1)
;
}
void machine_halt(void)
{
printk(KERN_NOTICE "Machine halt...\n");
while (1)
;
}
void machine_power_off(void)
{
printk(KERN_NOTICE "Machine power off...\n");
while (1)
;
}