// SPDX-License-Identifier: GPL-2.0-only

  /*
   * LED Class Core
   *
   * Copyright 2005-2006 Openedhand Ltd.
   *
   * Author: Richard Purdie <rpurdie@openedhand.com>

   */
  
  #include <linux/kernel.h>

  #include <linux/leds.h>

  #include <linux/list.h>
  #include <linux/module.h>

  #include <linux/mutex.h>

  #include <linux/of.h>

  #include <linux/property.h>

  #include <linux/rwsem.h>

  #include <linux/slab.h>

  #include <uapi/linux/uleds.h>

  #include "leds.h"

  DECLARE_RWSEM(leds_list_lock);

  EXPORT_SYMBOL_GPL(leds_list_lock);

  LIST_HEAD(leds_list);

  EXPORT_SYMBOL_GPL(leds_list);

  const char * const led_colors[LED_COLOR_ID_MAX] = {
  	[LED_COLOR_ID_WHITE] = "white",
  	[LED_COLOR_ID_RED] = "red",
  	[LED_COLOR_ID_GREEN] = "green",
  	[LED_COLOR_ID_BLUE] = "blue",
  	[LED_COLOR_ID_AMBER] = "amber",
  	[LED_COLOR_ID_VIOLET] = "violet",
  	[LED_COLOR_ID_YELLOW] = "yellow",
  	[LED_COLOR_ID_IR] = "ir",

  	[LED_COLOR_ID_MULTI] = "multicolor",

  	[LED_COLOR_ID_RGB] = "rgb",

  };
  EXPORT_SYMBOL_GPL(led_colors);

  static int __led_set_brightness(struct led_classdev *led_cdev,
  				enum led_brightness value)
  {
  	if (!led_cdev->brightness_set)
  		return -ENOTSUPP;
  
  	led_cdev->brightness_set(led_cdev, value);
  
  	return 0;
  }
  
  static int __led_set_brightness_blocking(struct led_classdev *led_cdev,
  					 enum led_brightness value)
  {
  	if (!led_cdev->brightness_set_blocking)
  		return -ENOTSUPP;
  
  	return led_cdev->brightness_set_blocking(led_cdev, value);
  }

  static void led_timer_function(struct timer_list *t)

  {

  	struct led_classdev *led_cdev = from_timer(led_cdev, t, blink_timer);

  	unsigned long brightness;
  	unsigned long delay;
  
  	if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {

  		led_set_brightness_nosleep(led_cdev, LED_OFF);

  		clear_bit(LED_BLINK_SW, &led_cdev->work_flags);

  		return;
  	}

  	if (test_and_clear_bit(LED_BLINK_ONESHOT_STOP,
  			       &led_cdev->work_flags)) {
  		clear_bit(LED_BLINK_SW, &led_cdev->work_flags);

  		return;
  	}
  
  	brightness = led_get_brightness(led_cdev);
  	if (!brightness) {
  		/* Time to switch the LED on. */

  		if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE,
  					&led_cdev->work_flags))
  			brightness = led_cdev->new_blink_brightness;
  		else
  			brightness = led_cdev->blink_brightness;

  		delay = led_cdev->blink_delay_on;
  	} else {
  		/* Store the current brightness value to be able
  		 * to restore it when the delay_off period is over.
  		 */

  		led_cdev->blink_brightness = brightness;

  		brightness = LED_OFF;
  		delay = led_cdev->blink_delay_off;
  	}

  	led_set_brightness_nosleep(led_cdev, brightness);

  
  	/* Return in next iteration if led is in one-shot mode and we are in
  	 * the final blink state so that the led is toggled each delay_on +
  	 * delay_off milliseconds in worst case.
  	 */

  	if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags)) {
  		if (test_bit(LED_BLINK_INVERT, &led_cdev->work_flags)) {

  			if (brightness)

  				set_bit(LED_BLINK_ONESHOT_STOP,
  					&led_cdev->work_flags);

  		} else {
  			if (!brightness)

  				set_bit(LED_BLINK_ONESHOT_STOP,
  					&led_cdev->work_flags);

  		}
  	}
  
  	mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
  }
  
  static void set_brightness_delayed(struct work_struct *ws)
  {
  	struct led_classdev *led_cdev =
  		container_of(ws, struct led_classdev, set_brightness_work);

  	int ret = 0;

  	if (test_and_clear_bit(LED_BLINK_DISABLE, &led_cdev->work_flags)) {

  		led_cdev->delayed_set_value = LED_OFF;
  		led_stop_software_blink(led_cdev);

  	}

  	ret = __led_set_brightness(led_cdev, led_cdev->delayed_set_value);
  	if (ret == -ENOTSUPP)
  		ret = __led_set_brightness_blocking(led_cdev,
  					led_cdev->delayed_set_value);

  	if (ret < 0 &&
  	    /* LED HW might have been unplugged, therefore don't warn */
  	    !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) &&
  	    (led_cdev->flags & LED_HW_PLUGGABLE)))

  		dev_err(led_cdev->dev,
  			"Setting an LED's brightness failed (%d)
  ", ret);

  }

  static void led_set_software_blink(struct led_classdev *led_cdev,
  				   unsigned long delay_on,
  				   unsigned long delay_off)
  {
  	int current_brightness;
  
  	current_brightness = led_get_brightness(led_cdev);
  	if (current_brightness)
  		led_cdev->blink_brightness = current_brightness;
  	if (!led_cdev->blink_brightness)
  		led_cdev->blink_brightness = led_cdev->max_brightness;

  	led_cdev->blink_delay_on = delay_on;
  	led_cdev->blink_delay_off = delay_off;

  	/* never on - just set to off */
  	if (!delay_on) {

  		led_set_brightness_nosleep(led_cdev, LED_OFF);

  		return;

  	}

  
  	/* never off - just set to brightness */
  	if (!delay_off) {

  		led_set_brightness_nosleep(led_cdev,
  					   led_cdev->blink_brightness);

  		return;
  	}

  	set_bit(LED_BLINK_SW, &led_cdev->work_flags);

  	mod_timer(&led_cdev->blink_timer, jiffies + 1);

  }

  static void led_blink_setup(struct led_classdev *led_cdev,

  		     unsigned long *delay_on,
  		     unsigned long *delay_off)

  {

  	if (!test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&

  	    led_cdev->blink_set &&

  	    !led_cdev->blink_set(led_cdev, delay_on, delay_off))
  		return;
  
  	/* blink with 1 Hz as default if nothing specified */
  	if (!*delay_on && !*delay_off)
  		*delay_on = *delay_off = 500;
  
  	led_set_software_blink(led_cdev, *delay_on, *delay_off);
  }

  void led_init_core(struct led_classdev *led_cdev)
  {
  	INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);

  	timer_setup(&led_cdev->blink_timer, led_timer_function, 0);

  }
  EXPORT_SYMBOL_GPL(led_init_core);

  void led_blink_set(struct led_classdev *led_cdev,
  		   unsigned long *delay_on,
  		   unsigned long *delay_off)
  {

  	del_timer_sync(&led_cdev->blink_timer);

  	clear_bit(LED_BLINK_SW, &led_cdev->work_flags);

  	clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
  	clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);

  
  	led_blink_setup(led_cdev, delay_on, delay_off);
  }

  EXPORT_SYMBOL_GPL(led_blink_set);

  void led_blink_set_oneshot(struct led_classdev *led_cdev,
  			   unsigned long *delay_on,
  			   unsigned long *delay_off,
  			   int invert)
  {

  	if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&

  	     timer_pending(&led_cdev->blink_timer))

  		return;

  	set_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
  	clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);

  
  	if (invert)

  		set_bit(LED_BLINK_INVERT, &led_cdev->work_flags);

  	else

  		clear_bit(LED_BLINK_INVERT, &led_cdev->work_flags);

  
  	led_blink_setup(led_cdev, delay_on, delay_off);
  }

  EXPORT_SYMBOL_GPL(led_blink_set_oneshot);

  void led_stop_software_blink(struct led_classdev *led_cdev)

  {

  	del_timer_sync(&led_cdev->blink_timer);

  	led_cdev->blink_delay_on = 0;
  	led_cdev->blink_delay_off = 0;

  	clear_bit(LED_BLINK_SW, &led_cdev->work_flags);

  }
  EXPORT_SYMBOL_GPL(led_stop_software_blink);
  
  void led_set_brightness(struct led_classdev *led_cdev,
  			enum led_brightness brightness)
  {

  	/*

  	 * If software blink is active, delay brightness setting

  	 * until the next timer tick.
  	 */

  	if (test_bit(LED_BLINK_SW, &led_cdev->work_flags)) {

  		/*
  		 * If we need to disable soft blinking delegate this to the
  		 * work queue task to avoid problems in case we are called
  		 * from hard irq context.
  		 */
  		if (brightness == LED_OFF) {

  			set_bit(LED_BLINK_DISABLE, &led_cdev->work_flags);

  			schedule_work(&led_cdev->set_brightness_work);

  		} else {

  			set_bit(LED_BLINK_BRIGHTNESS_CHANGE,
  				&led_cdev->work_flags);

  			led_cdev->new_blink_brightness = brightness;

  		}

  		return;
  	}

  	led_set_brightness_nosleep(led_cdev, brightness);

  }

  EXPORT_SYMBOL_GPL(led_set_brightness);

  void led_set_brightness_nopm(struct led_classdev *led_cdev,
  			      enum led_brightness value)
  {
  	/* Use brightness_set op if available, it is guaranteed not to sleep */

  	if (!__led_set_brightness(led_cdev, value))

  		return;

  
  	/* If brightness setting can sleep, delegate it to a work queue task */
  	led_cdev->delayed_set_value = value;
  	schedule_work(&led_cdev->set_brightness_work);
  }
  EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
  
  void led_set_brightness_nosleep(struct led_classdev *led_cdev,
  				enum led_brightness value)
  {
  	led_cdev->brightness = min(value, led_cdev->max_brightness);
  
  	if (led_cdev->flags & LED_SUSPENDED)
  		return;
  
  	led_set_brightness_nopm(led_cdev, led_cdev->brightness);
  }
  EXPORT_SYMBOL_GPL(led_set_brightness_nosleep);

  int led_set_brightness_sync(struct led_classdev *led_cdev,
  			    enum led_brightness value)
  {
  	if (led_cdev->blink_delay_on || led_cdev->blink_delay_off)
  		return -EBUSY;
  
  	led_cdev->brightness = min(value, led_cdev->max_brightness);
  
  	if (led_cdev->flags & LED_SUSPENDED)
  		return 0;

  	return __led_set_brightness_blocking(led_cdev, led_cdev->brightness);

  }
  EXPORT_SYMBOL_GPL(led_set_brightness_sync);

  int led_update_brightness(struct led_classdev *led_cdev)
  {
  	int ret = 0;
  
  	if (led_cdev->brightness_get) {
  		ret = led_cdev->brightness_get(led_cdev);
  		if (ret >= 0) {
  			led_cdev->brightness = ret;
  			return 0;
  		}
  	}
  
  	return ret;
  }

  EXPORT_SYMBOL_GPL(led_update_brightness);

  u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size)
  {

  	struct fwnode_handle *fwnode = led_cdev->dev->fwnode;

  	u32 *pattern;
  	int count;

  	count = fwnode_property_count_u32(fwnode, "led-pattern");

  	if (count < 0)
  		return NULL;
  
  	pattern = kcalloc(count, sizeof(*pattern), GFP_KERNEL);
  	if (!pattern)
  		return NULL;

  	if (fwnode_property_read_u32_array(fwnode, "led-pattern", pattern, count)) {

  		kfree(pattern);
  		return NULL;
  	}
  
  	*size = count;
  
  	return pattern;
  }
  EXPORT_SYMBOL_GPL(led_get_default_pattern);

  /* Caller must ensure led_cdev->led_access held */
  void led_sysfs_disable(struct led_classdev *led_cdev)
  {
  	lockdep_assert_held(&led_cdev->led_access);
  
  	led_cdev->flags |= LED_SYSFS_DISABLE;
  }
  EXPORT_SYMBOL_GPL(led_sysfs_disable);
  
  /* Caller must ensure led_cdev->led_access held */
  void led_sysfs_enable(struct led_classdev *led_cdev)
  {
  	lockdep_assert_held(&led_cdev->led_access);
  
  	led_cdev->flags &= ~LED_SYSFS_DISABLE;
  }
  EXPORT_SYMBOL_GPL(led_sysfs_enable);

  
  static void led_parse_fwnode_props(struct device *dev,
  				   struct fwnode_handle *fwnode,
  				   struct led_properties *props)
  {
  	int ret;
  
  	if (!fwnode)
  		return;
  
  	if (fwnode_property_present(fwnode, "label")) {
  		ret = fwnode_property_read_string(fwnode, "label", &props->label);
  		if (ret)
  			dev_err(dev, "Error parsing 'label' property (%d)
  ", ret);
  		return;
  	}
  
  	if (fwnode_property_present(fwnode, "color")) {
  		ret = fwnode_property_read_u32(fwnode, "color", &props->color);
  		if (ret)
  			dev_err(dev, "Error parsing 'color' property (%d)
  ", ret);
  		else if (props->color >= LED_COLOR_ID_MAX)
  			dev_err(dev, "LED color identifier out of range
  ");
  		else
  			props->color_present = true;
  	}
  
  
  	if (!fwnode_property_present(fwnode, "function"))
  		return;
  
  	ret = fwnode_property_read_string(fwnode, "function", &props->function);
  	if (ret) {
  		dev_err(dev,
  			"Error parsing 'function' property (%d)
  ",
  			ret);
  	}
  
  	if (!fwnode_property_present(fwnode, "function-enumerator"))
  		return;
  
  	ret = fwnode_property_read_u32(fwnode, "function-enumerator",
  				       &props->func_enum);
  	if (ret) {
  		dev_err(dev,
  			"Error parsing 'function-enumerator' property (%d)
  ",
  			ret);
  	} else {
  		props->func_enum_present = true;
  	}
  }
  
  int led_compose_name(struct device *dev, struct led_init_data *init_data,
  		     char *led_classdev_name)
  {
  	struct led_properties props = {};
  	struct fwnode_handle *fwnode = init_data->fwnode;
  	const char *devicename = init_data->devicename;

  	/* We want to label LEDs that can produce full range of colors
  	 * as RGB, not multicolor */
  	BUG_ON(props.color == LED_COLOR_ID_MULTI);

  	if (!led_classdev_name)
  		return -EINVAL;
  
  	led_parse_fwnode_props(dev, fwnode, &props);
  
  	if (props.label) {
  		/*
  		 * If init_data.devicename is NULL, then it indicates that
  		 * DT label should be used as-is for LED class device name.
  		 * Otherwise the label is prepended with devicename to compose
  		 * the final LED class device name.
  		 */
  		if (!devicename) {
  			strscpy(led_classdev_name, props.label,
  				LED_MAX_NAME_SIZE);
  		} else {
  			snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
  				 devicename, props.label);
  		}
  	} else if (props.function || props.color_present) {
  		char tmp_buf[LED_MAX_NAME_SIZE];
  
  		if (props.func_enum_present) {
  			snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s-%d",
  				 props.color_present ? led_colors[props.color] : "",
  				 props.function ?: "", props.func_enum);
  		} else {
  			snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s",
  				 props.color_present ? led_colors[props.color] : "",
  				 props.function ?: "");
  		}
  		if (init_data->devname_mandatory) {
  			snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
  				 devicename, tmp_buf);
  		} else {
  			strscpy(led_classdev_name, tmp_buf, LED_MAX_NAME_SIZE);
  
  		}
  	} else if (init_data->default_label) {
  		if (!devicename) {
  			dev_err(dev, "Legacy LED naming requires devicename segment");
  			return -EINVAL;
  		}
  		snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
  			 devicename, init_data->default_label);
  	} else if (is_of_node(fwnode)) {
  		strscpy(led_classdev_name, to_of_node(fwnode)->name,
  			LED_MAX_NAME_SIZE);
  	} else
  		return -EINVAL;
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(led_compose_name);