/* * Control GPIO pins on the fly * * Copyright (c) 2008-2011 Analog Devices Inc. * * Licensed under the GPL-2 or later. */ #include #include #include #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_RET_USAGE; 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", " \n" " - input/set/clear/toggle the specified pin");