Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / arch / microblaze / kernel / reset.c
blobbd8ccab5ceff407287d3114d444ac467812a225f
1 /*
2 * Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
3 * Copyright (C) 2009 PetaLogix
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 */
10 #include <linux/init.h>
11 #include <linux/of_platform.h>
12 #include <asm/prom.h>
14 /* Trigger specific functions */
15 #ifdef CONFIG_GPIOLIB
17 #include <linux/of_gpio.h>
19 static int handle; /* reset pin handle */
20 static unsigned int reset_val;
22 static int of_reset_gpio_handle(void)
24 int ret; /* variable which stored handle reset gpio pin */
25 struct device_node *root; /* root node */
26 struct device_node *gpio; /* gpio node */
27 struct gpio_chip *gc;
28 u32 flags;
29 const void *gpio_spec;
31 /* find out root node */
32 root = of_find_node_by_path("/");
34 /* give me handle for gpio node to be possible allocate pin */
35 ret = of_parse_phandles_with_args(root, "hard-reset-gpios",
36 "#gpio-cells", 0, &gpio, &gpio_spec);
37 if (ret) {
38 pr_debug("%s: can't parse gpios property\n", __func__);
39 goto err0;
42 gc = of_node_to_gpiochip(gpio);
43 if (!gc) {
44 pr_debug("%s: gpio controller %s isn't registered\n",
45 root->full_name, gpio->full_name);
46 ret = -ENODEV;
47 goto err1;
50 ret = gc->of_xlate(gc, root, gpio_spec, &flags);
51 if (ret < 0)
52 goto err1;
54 ret += gc->base;
55 err1:
56 of_node_put(gpio);
57 err0:
58 pr_debug("%s exited with status %d\n", __func__, ret);
59 return ret;
62 void of_platform_reset_gpio_probe(void)
64 int ret;
65 handle = of_reset_gpio_handle();
67 if (!gpio_is_valid(handle)) {
68 printk(KERN_INFO "Skipping unavailable RESET gpio %d (%s)\n",
69 handle, "reset");
72 ret = gpio_request(handle, "reset");
73 if (ret < 0) {
74 printk(KERN_INFO "GPIO pin is already allocated\n");
75 return;
78 /* get current setup value */
79 reset_val = gpio_get_value(handle);
80 /* FIXME maybe worth to perform any action */
81 pr_debug("Reset: Gpio output state: 0x%x\n", reset_val);
83 /* Setup GPIO as output */
84 ret = gpio_direction_output(handle, 0);
85 if (ret < 0)
86 goto err;
88 /* Setup output direction */
89 gpio_set_value(handle, 0);
91 printk(KERN_INFO "RESET: Registered gpio device: %d, current val: %d\n",
92 handle, reset_val);
93 return;
94 err:
95 gpio_free(handle);
96 return;
100 static void gpio_system_reset(void)
102 gpio_set_value(handle, 1 - reset_val);
104 #else
105 #define gpio_system_reset() do {} while (0)
106 void of_platform_reset_gpio_probe(void)
108 return;
110 #endif
112 void machine_restart(char *cmd)
114 printk(KERN_NOTICE "Machine restart...\n");
115 gpio_system_reset();
116 dump_stack();
117 while (1)
121 void machine_shutdown(void)
123 printk(KERN_NOTICE "Machine shutdown...\n");
124 while (1)
128 void machine_halt(void)
130 printk(KERN_NOTICE "Machine halt...\n");
131 while (1)
135 void machine_power_off(void)
137 printk(KERN_NOTICE "Machine power off...\n");
138 while (1)