Skip to content
Snippets Groups Projects
cmd_gpio.c 1.86 KiB
Newer Older
  • Learn to ignore specific revisions
  • /*
     * Control GPIO pins on the fly
     *
     * Copyright (c) 2008-2011 Analog Devices Inc.
     *
     * Licensed under the GPL-2 or later.
     */
    
    #include <common.h>
    #include <command.h>
    
    #include <asm/gpio.h>
    
    #ifndef name_to_gpio
    #define name_to_gpio(name) simple_strtoul(name, NULL, 10)
    #endif
    
    enum gpio_cmd {
    	GPIO_INPUT,
    	GPIO_SET,
    	GPIO_CLEAR,
    	GPIO_TOGGLE,
    };
    
    static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
    {
    	int gpio;
    	enum gpio_cmd sub_cmd;
    	ulong value;
    	const char *str_cmd, *str_gpio;
    
    #ifdef gpio_status
    	if (argc == 2 && !strcmp(argv[1], "status")) {
    		gpio_status();
    		return 0;
    	}
    #endif
    
    	if (argc != 3)
     show_usage:
    		return cmd_usage(cmdtp);
    	str_cmd = argv[1];
    	str_gpio = argv[2];
    
    	/* parse the behavior */
    	switch (*str_cmd) {
    		case 'i': sub_cmd = GPIO_INPUT;  break;
    		case 's': sub_cmd = GPIO_SET;    break;
    		case 'c': sub_cmd = GPIO_CLEAR;  break;
    		case 't': sub_cmd = GPIO_TOGGLE; break;
    		default:  goto show_usage;
    	}
    
    	/* turn the gpio name into a gpio number */
    	gpio = name_to_gpio(str_gpio);
    	if (gpio < 0)
    		goto show_usage;
    
    	/* grab the pin before we tweak it */
    
    	if (gpio_request(gpio, "cmd_gpio")) {
    		printf("gpio: requesting pin %u failed\n", gpio);
    		return -1;
    	}
    
    
    	/* finally, let's do it: set direction and exec command */
    	if (sub_cmd == GPIO_INPUT) {
    		gpio_direction_input(gpio);
    		value = gpio_get_value(gpio);
    	} else {
    		switch (sub_cmd) {
    			case GPIO_SET:    value = 1; break;
    			case GPIO_CLEAR:  value = 0; break;
    			case GPIO_TOGGLE: value = !gpio_get_value(gpio); break;
    			default:          goto show_usage;
    		}
    		gpio_direction_output(gpio, value);
    	}
    	printf("gpio: pin %s (gpio %i) value is %lu\n",
    		str_gpio, gpio, value);
    
    	gpio_free(gpio);
    
    	return value;
    }
    
    U_BOOT_CMD(gpio, 3, 0, do_gpio,
    	"input/set/clear/toggle gpio pins",
    	"<input|set|clear|toggle> <pin>\n"
    	"    - input/set/clear/toggle the specified pin");