diff options
Diffstat (limited to 'common/cmd_gpio.c')
-rw-r--r-- | common/cmd_gpio.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/common/cmd_gpio.c b/common/cmd_gpio.c new file mode 100644 index 0000000000..9cc790aba8 --- /dev/null +++ b/common/cmd_gpio.c @@ -0,0 +1,89 @@ +/* + * 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"); |