LXR linux/arch/microblaze/kernel/reset.c

   1/*
   2 * Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
   3 * Copyright (C) 2009 PetaLogix
   4 *
   5 * This file is subject to the terms and conditions of the GNU General Public
   6 * License. See the file "COPYING" in the main directory of this archive
   7 * for more details.
   8 */
   9
  10#include <linux/init.h>
  11#include <linux/of_platform.h>
  12#include <asm/prom.h>
  13
  14/* Trigger specific functions */
  15#ifdef CONFIG_GPIOLIB
  16
  17#include <linux/of_gpio.h>
  18
  19static int handle; /* reset pin handle */
  20static unsigned int reset_val;
  21
  22void of_platform_reset_gpio_probe(void)
  23{
  24        int ret;
  25        handle = of_get_named_gpio(of_find_node_by_path("/"),
  26                                   "hard-reset-gpios", 0);
  27
  28        if (!gpio_is_valid(handle)) {
  29                pr_info("Skipping unavailable RESET gpio %d (%s)\n",
  30                                handle, "reset");
  31                return;
  32        }
  33
  34        ret = gpio_request(handle, "reset");
  35        if (ret < 0) {
  36                pr_info("GPIO pin is already allocated\n");
  37                return;
  38        }
  39
  40        /* get current setup value */
  41        reset_val = gpio_get_value(handle);
  42        /* FIXME maybe worth to perform any action */
  43        pr_debug("Reset: Gpio output state: 0x%x\n", reset_val);
  44
  45        /* Setup GPIO as output */
  46        ret = gpio_direction_output(handle, 0);
  47        if (ret < 0)
  48                goto err;
  49
  50        /* Setup output direction */
  51        gpio_set_value(handle, 0);
  52
  53        pr_info("RESET: Registered gpio device: %d, current val: %d\n",
  54                                                        handle, reset_val);
  55        return;
  56err:
  57        gpio_free(handle);
  58        return;
  59}
  60
  61
  62static void gpio_system_reset(void)
  63{
  64        if (gpio_is_valid(handle))
  65                gpio_set_value(handle, 1 - reset_val);
  66        else
  67                pr_notice("Reset GPIO unavailable - halting!\n");
  68}
  69#else
  70static void gpio_system_reset(void)
  71{
  72        pr_notice("No reset GPIO present - halting!\n");
  73}
  74
  75void of_platform_reset_gpio_probe(void)
  76{
  77        return;
  78}
  79#endif
  80
  81void machine_restart(char *cmd)
  82{
  83        pr_notice("Machine restart...\n");
  84        gpio_system_reset();
  85        while (1)
  86                ;
  87}
  88
  89void machine_shutdown(void)
  90{
  91        pr_notice("Machine shutdown...\n");
  92        while (1)
  93                ;
  94}
  95
  96void machine_halt(void)
  97{
  98        pr_notice("Machine halt...\n");
  99        while (1)
 100                ;
 101}
 102
 103void machine_power_off(void)
 104{
 105        pr_notice("Machine power off...\n");
 106        while (1)
 107                ;
 108}
 109