/*
   * 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 <errno.h>

  #include <dm.h>

  #include <malloc.h>

  #include <asm/gpio.h>

  #include <linux/err.h>

  __weak int name_to_gpio(const char *name)

  {
  	return simple_strtoul(name, NULL, 10);
  }

  
  enum gpio_cmd {

  	GPIOC_INPUT,
  	GPIOC_SET,
  	GPIOC_CLEAR,
  	GPIOC_TOGGLE,

  };

  #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('
  ');
  			*flagsp &= ~FLAG_SHOW_NEWLINE;
  		}
  		printf("Bank %s:
  ", bank_name);
  		*flagsp &= ~FLAG_SHOW_BANK;
  	}

  	ret = gpio_get_status(dev, offset, buf, sizeof(buf));
  	if (ret)
  		goto err;
  
  	printf("%s
  ", buf);
  	return;
  err:
  	printf("Error %d
  ", ret);

  }

  static int do_gpio_status(bool all, const char *gpio_name)

  {

  	struct udevice *dev;

  	int banklen;
  	int flags;

  	int ret;

  	flags = 0;

  	if (gpio_name && !*gpio_name)
  		gpio_name = NULL;
  	for (ret = uclass_first_device(UCLASS_GPIO, &dev);
  	     dev;
  	     ret = uclass_next_device(&dev)) {
  		const char *bank_name;
  		int num_bits;

  		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
  ", 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 = simple_strtoul(p, NULL, 10);

  				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 ret;
  }
  #endif

  static int do_gpio(cmd_tbl_t *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;

  	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 && !strcmp(*argv, "-a")) {
  		all = true;
  		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;
  	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
  ", 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
  ", gpio);
  		return -1;
  	}

  
  	/* finally, let's do it: set direction and exec command */

  	if (sub_cmd == GPIOC_INPUT) {

  		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)
  ", value);

  		goto err;
  	} else {

  		printf("%d
  ", value);

  	}

  	if (sub_cmd != GPIOC_INPUT && !IS_ERR_VALUE(value)) {

  		int nval = gpio_get_value(gpio);

  		if (IS_ERR_VALUE(nval)) {

  			printf("   Warning: no access to GPIO output value
  ");

  			goto err;
  		} else if (nval != value) {

  			printf("   Warning: value of pin is still %d
  ", 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",
  	   "<input|set|clear|toggle> <pin>
  "
  	   "    - input/set/clear/toggle the specified pin
  "
  	   "gpio status [-a] [<bank> | <pin>]  - show [all/claimed] GPIOs");