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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;
static int of_reset_gpio_handle(void)
{
int ret; /* variable which stored handle reset gpio pin */
struct device_node *root; /* root node */
struct device_node *gpio; /* gpio node */
struct gpio_chip *gc;
u32 flags;
const void *gpio_spec;
/* find out root node */
root = of_find_node_by_path("/");
/* give me handle for gpio node to be possible allocate pin */
ret = of_parse_phandles_with_args(root, "hard-reset-gpios",
"#gpio-cells", 0, &gpio, &gpio_spec);
if (ret) {
pr_debug("%s: can't parse gpios property\n", __func__);
goto err0;
}
gc = of_node_to_gpiochip(gpio);
if (!gc) {
pr_debug("%s: gpio controller %s isn't registered\n",
root->full_name, gpio->full_name);
ret = -ENODEV;
goto err1;
}
ret = gc->of_xlate(gc, root, gpio_spec, &flags);
if (ret < 0)
goto err1;
ret += gc->base;
err1:
of_node_put(gpio);
err0:
pr_debug("%s exited with status %d\n", __func__, ret);
return ret;
}
void of_platform_reset_gpio_probe(void)
{
int ret;
handle = of_reset_gpio_handle();
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)
;
}
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