/* * Control GPIO pins on the fly * * Copyright (c) 2008-2011 Analog Devices Inc. * * Licensed under the GPL-2 or later. */ #include #include #include #include #include #ifdef CONFIG_CMD_GPIO_READ #include #endif #include #include #include __weak int name_to_gpio(const char *name) { return dectoul(name, NULL); } enum gpio_cmd { GPIOC_INPUT, GPIOC_SET, GPIOC_CLEAR, GPIOC_TOGGLE, #ifdef CONFIG_CMD_GPIO_READ GPIOC_READ, #endif }; #if defined(CONFIG_DM_GPIO) && !defined(gpio_status) /* A few flags used by show_gpio() */ enum { FLAG_SHOW_ALL = 1 << 0, FLAG_SHOW_BANK = 1 << 1, FLAG_SHOW_NEWLINE = 1 << 2, }; static void gpio_get_description(struct udevice *dev, const char *bank_name, int offset, int *flagsp, bool show_all) { char buf[80]; int ret; ret = gpio_get_function(dev, offset, NULL); if (ret < 0) goto err; if (!show_all && !(*flagsp & FLAG_SHOW_ALL) && ret == GPIOF_UNUSED) return; if ((*flagsp & FLAG_SHOW_BANK) && bank_name) { if (*flagsp & FLAG_SHOW_NEWLINE) { putc('\n'); *flagsp &= ~FLAG_SHOW_NEWLINE; } printf("Bank %s:\n", bank_name); *flagsp &= ~FLAG_SHOW_BANK; } ret = gpio_get_status(dev, offset, buf, sizeof(buf)); if (ret) goto err; printf("%s\n", buf); return; err: if (ret != -ENOENT) printf("Error %d\n", ret); } static int do_gpio_status(bool all, const char *gpio_name) { struct udevice *dev; int banklen; int flags; int ret, err = 0; flags = 0; if (gpio_name && !*gpio_name) gpio_name = NULL; for (ret = uclass_first_device_check(UCLASS_GPIO, &dev); dev; ret = uclass_next_device_check(&dev)) { const char *bank_name; int num_bits; if (ret) { printf("GPIO device %s probe error %i\n", dev->name, ret); err = ret; continue; } flags |= FLAG_SHOW_BANK; if (all) flags |= FLAG_SHOW_ALL; bank_name = gpio_get_bank_info(dev, &num_bits); if (!num_bits) { debug("GPIO device %s has no bits\n", dev->name); continue; } banklen = bank_name ? strlen(bank_name) : 0; if (!gpio_name || !bank_name || !strncasecmp(gpio_name, bank_name, banklen)) { const char *p; int offset; p = gpio_name + banklen; if (gpio_name && *p) { offset = dectoul(p, NULL); gpio_get_description(dev, bank_name, offset, &flags, true); } else { for (offset = 0; offset < num_bits; offset++) { gpio_get_description(dev, bank_name, offset, &flags, false); } } } /* Add a newline between bank names */ if (!(flags & FLAG_SHOW_BANK)) flags |= FLAG_SHOW_NEWLINE; } return err; } #endif static int do_gpio(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { unsigned int gpio; enum gpio_cmd sub_cmd; int value; const char *str_cmd, *str_gpio = NULL; #ifdef CONFIG_CMD_GPIO_READ const char *str_var = NULL; #endif int ret; #ifdef CONFIG_DM_GPIO bool all = false; #endif if (argc < 2) show_usage: return CMD_RET_USAGE; str_cmd = argv[1]; argc -= 2; argv += 2; #ifdef CONFIG_DM_GPIO if (argc > 0 && !strncmp(str_cmd, "status", 2) && !strcmp(*argv, "-a")) { all = true; argc--; argv++; } #endif #ifdef CONFIG_CMD_GPIO_READ if (argc > 0 && !strncmp(str_cmd, "read", 2)) { if (argc < 2) goto show_usage; str_var = *argv; argc--; argv++; } #endif if (argc > 0) str_gpio = *argv; if (!strncmp(str_cmd, "status", 2)) { /* Support deprecated gpio_status() */ #ifdef gpio_status gpio_status(); return 0; #elif defined(CONFIG_DM_GPIO) return cmd_process_error(cmdtp, do_gpio_status(all, str_gpio)); #else goto show_usage; #endif } if (!str_gpio) goto show_usage; /* parse the behavior */ switch (*str_cmd) { case 'i': sub_cmd = GPIOC_INPUT; break; case 's': sub_cmd = GPIOC_SET; break; case 'c': sub_cmd = GPIOC_CLEAR; break; case 't': sub_cmd = GPIOC_TOGGLE; break; #ifdef CONFIG_CMD_GPIO_READ case 'r': sub_cmd = GPIOC_READ; break; #endif default: goto show_usage; } #if defined(CONFIG_DM_GPIO) /* * TODO(sjg@chromium.org): For now we must fit into the existing GPIO * framework, so we look up the name here and convert it to a GPIO number. * Once all GPIO drivers are converted to driver model, we can change the * code here to use the GPIO uclass interface instead of the numbered * GPIO compatibility layer. */ ret = gpio_lookup_name(str_gpio, NULL, NULL, &gpio); if (ret) { printf("GPIO: '%s' not found\n", str_gpio); return cmd_process_error(cmdtp, ret); } #else /* turn the gpio name into a gpio number */ gpio = name_to_gpio(str_gpio); if (gpio < 0) goto show_usage; #endif /* grab the pin before we tweak it */ ret = gpio_request(gpio, "cmd_gpio"); if (ret && ret != -EBUSY) { printf("gpio: requesting pin %u failed\n", gpio); return -1; } /* finally, let's do it: set direction and exec command */ if (sub_cmd == GPIOC_INPUT #ifdef CONFIG_CMD_GPIO_READ || sub_cmd == GPIOC_READ #endif ) { gpio_direction_input(gpio); value = gpio_get_value(gpio); } else { switch (sub_cmd) { case GPIOC_SET: value = 1; break; case GPIOC_CLEAR: value = 0; break; case GPIOC_TOGGLE: value = gpio_get_value(gpio); if (!IS_ERR_VALUE(value)) value = !value; break; default: goto show_usage; } gpio_direction_output(gpio, value); } printf("gpio: pin %s (gpio %u) value is ", str_gpio, gpio); if (IS_ERR_VALUE(value)) { printf("unknown (ret=%d)\n", value); goto err; } else { printf("%d\n", value); #ifdef CONFIG_CMD_GPIO_READ if (sub_cmd == GPIOC_READ) env_set_ulong(str_var, (ulong)value); #endif } if (sub_cmd != GPIOC_INPUT && !IS_ERR_VALUE(value) #ifdef CONFIG_CMD_GPIO_READ && sub_cmd != GPIOC_READ #endif ) { int nval = gpio_get_value(gpio); if (IS_ERR_VALUE(nval)) { printf(" Warning: no access to GPIO output value\n"); goto err; } else if (nval != value) { printf(" Warning: value of pin is still %d\n", nval); goto err; } } if (ret != -EBUSY) gpio_free(gpio); /* * Whilst wrong, the legacy gpio input command returns the pin * value, or CMD_RET_FAILURE (which is indistinguishable from a * valid pin value). */ return (sub_cmd == GPIOC_INPUT) ? value : CMD_RET_SUCCESS; err: if (ret != -EBUSY) gpio_free(gpio); return CMD_RET_FAILURE; } U_BOOT_CMD(gpio, 4, 0, do_gpio, "query and control gpio pins", " \n" " - input/set/clear/toggle the specified pin\n" #ifdef CONFIG_CMD_GPIO_READ "gpio read \n" " - set environment variable 'name' to the specified pin\n" #endif "gpio status [-a] [ | ] - show [all/claimed] GPIOs");