/* * Copyright (C) 2009 Michal Simek * 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 #include #include /* Trigger specific functions */ #ifdef CONFIG_GPIOLIB #include 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) ; }