text: // SPDX-License-Identifier: GPL-2.0
  // rc-main.c - Remote Controller core module
  //
  // Copyright (C) 2009-2010 by Mauro Carvalho Chehab
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
  #include <media/rc-core.h>
  #include <linux/bsearch.h>
  #include <linux/spinlock.h>
  #include <linux/delay.h>
  #include <linux/input.h>
  #include <linux/leds.h>
  #include <linux/slab.h>
  #include <linux/idr.h>
  #include <linux/device.h>
  #include <linux/module.h>
  #include "rc-core-priv.h"
  
  /* Sizes are in bytes, 256 bytes allows for 32 entries on x64 */
  #define IR_TAB_MIN_SIZE	256
  #define IR_TAB_MAX_SIZE	8192
  
  static const struct {
  	const char *name;
  	unsigned int repeat_period;
  	unsigned int scancode_bits;
  } protocols[] = {
  	[RC_PROTO_UNKNOWN] = { .name = "unknown", .repeat_period = 125 },
  	[RC_PROTO_OTHER] = { .name = "other", .repeat_period = 125 },
  	[RC_PROTO_RC5] = { .name = "rc-5",
  		.scancode_bits = 0x1f7f, .repeat_period = 114 },
  	[RC_PROTO_RC5X_20] = { .name = "rc-5x-20",
  		.scancode_bits = 0x1f7f3f, .repeat_period = 114 },
  	[RC_PROTO_RC5_SZ] = { .name = "rc-5-sz",
  		.scancode_bits = 0x2fff, .repeat_period = 114 },
  	[RC_PROTO_JVC] = { .name = "jvc",
  		.scancode_bits = 0xffff, .repeat_period = 125 },
  	[RC_PROTO_SONY12] = { .name = "sony-12",
  		.scancode_bits = 0x1f007f, .repeat_period = 100 },
  	[RC_PROTO_SONY15] = { .name = "sony-15",
  		.scancode_bits = 0xff007f, .repeat_period = 100 },
  	[RC_PROTO_SONY20] = { .name = "sony-20",
  		.scancode_bits = 0x1fff7f, .repeat_period = 100 },
  	[RC_PROTO_NEC] = { .name = "nec",
  		.scancode_bits = 0xffff, .repeat_period = 110 },
  	[RC_PROTO_NECX] = { .name = "nec-x",
  		.scancode_bits = 0xffffff, .repeat_period = 110 },
  	[RC_PROTO_NEC32] = { .name = "nec-32",
  		.scancode_bits = 0xffffffff, .repeat_period = 110 },
  	[RC_PROTO_SANYO] = { .name = "sanyo",
  		.scancode_bits = 0x1fffff, .repeat_period = 125 },
  	[RC_PROTO_MCIR2_KBD] = { .name = "mcir2-kbd",
  		.scancode_bits = 0xffffff, .repeat_period = 100 },
  	[RC_PROTO_MCIR2_MSE] = { .name = "mcir2-mse",
  		.scancode_bits = 0x1fffff, .repeat_period = 100 },
  	[RC_PROTO_RC6_0] = { .name = "rc-6-0",
  		.scancode_bits = 0xffff, .repeat_period = 114 },
  	[RC_PROTO_RC6_6A_20] = { .name = "rc-6-6a-20",
  		.scancode_bits = 0xfffff, .repeat_period = 114 },
  	[RC_PROTO_RC6_6A_24] = { .name = "rc-6-6a-24",
  		.scancode_bits = 0xffffff, .repeat_period = 114 },
  	[RC_PROTO_RC6_6A_32] = { .name = "rc-6-6a-32",
  		.scancode_bits = 0xffffffff, .repeat_period = 114 },
  	[RC_PROTO_RC6_MCE] = { .name = "rc-6-mce",
  		.scancode_bits = 0xffff7fff, .repeat_period = 114 },
  	[RC_PROTO_SHARP] = { .name = "sharp",
  		.scancode_bits = 0x1fff, .repeat_period = 125 },
  	[RC_PROTO_XMP] = { .name = "xmp", .repeat_period = 125 },
  	[RC_PROTO_CEC] = { .name = "cec", .repeat_period = 0 },
  	[RC_PROTO_IMON] = { .name = "imon",
  		.scancode_bits = 0x7fffffff, .repeat_period = 114 },
  };
  
  /* Used to keep track of known keymaps */
  static LIST_HEAD(rc_map_list);
  static DEFINE_SPINLOCK(rc_map_lock);
  static struct led_trigger *led_feedback;
  
  /* Used to keep track of rc devices */
  static DEFINE_IDA(rc_ida);
  
  static struct rc_map_list *seek_rc_map(const char *name)
  {
  	struct rc_map_list *map = NULL;
  
  	spin_lock(&rc_map_lock);
  	list_for_each_entry(map, &rc_map_list, list) {
  		if (!strcmp(name, map->map.name)) {
  			spin_unlock(&rc_map_lock);
  			return map;
  		}
  	}
  	spin_unlock(&rc_map_lock);
  
  	return NULL;
  }
  
  struct rc_map *rc_map_get(const char *name)
  {
  
  	struct rc_map_list *map;
  
  	map = seek_rc_map(name);
  #ifdef CONFIG_MODULES
  	if (!map) {
  		int rc = request_module("%s", name);
  		if (rc < 0) {
  			pr_err("Couldn't load IR keymap %s\n", name);
  			return NULL;
  		}
  		msleep(20);	/* Give some time for IR to register */
  
  		map = seek_rc_map(name);
  	}
  #endif
  	if (!map) {
  		pr_err("IR keymap %s not found\n", name);
  		return NULL;
  	}
  
  	printk(KERN_INFO "Registered IR keymap %s\n", map->map.name);
  
  	return &map->map;
  }
  EXPORT_SYMBOL_GPL(rc_map_get);
  
  int rc_map_register(struct rc_map_list *map)
  {
  	spin_lock(&rc_map_lock);
  	list_add_tail(&map->list, &rc_map_list);
  	spin_unlock(&rc_map_lock);
  	return 0;
  }
  EXPORT_SYMBOL_GPL(rc_map_register);
  
  void rc_map_unregister(struct rc_map_list *map)
  {
  	spin_lock(&rc_map_lock);
  	list_del(&map->list);
  	spin_unlock(&rc_map_lock);
  }
  EXPORT_SYMBOL_GPL(rc_map_unregister);
  
  
  static struct rc_map_table empty[] = {
  	{ 0x2a, KEY_COFFEE },
  };
  
  static struct rc_map_list empty_map = {
  	.map = {
  		.scan     = empty,
  		.size     = ARRAY_SIZE(empty),
  		.rc_proto = RC_PROTO_UNKNOWN,	/* Legacy IR type */
  		.name     = RC_MAP_EMPTY,
  	}
  };
  
  /**
   * ir_create_table() - initializes a scancode table
   * @dev:	the rc_dev device
   * @rc_map:	the rc_map to initialize
   * @name:	name to assign to the table
   * @rc_proto:	ir type to assign to the new table
   * @size:	initial size of the table
   *
   * This routine will initialize the rc_map and will allocate
   * memory to hold at least the specified number of elements.
   *
   * return:	zero on success or a negative error code
   */
  static int ir_create_table(struct rc_dev *dev, struct rc_map *rc_map,
  			   const char *name, u64 rc_proto, size_t size)
  {
  	rc_map->name = kstrdup(name, GFP_KERNEL);
  	if (!rc_map->name)
  		return -ENOMEM;
  	rc_map->rc_proto = rc_proto;
  	rc_map->alloc = roundup_pow_of_two(size * sizeof(struct rc_map_table));
  	rc_map->size = rc_map->alloc / sizeof(struct rc_map_table);
  	rc_map->scan = kmalloc(rc_map->alloc, GFP_KERNEL);
  	if (!rc_map->scan) {
  		kfree(rc_map->name);
  		rc_map->name = NULL;
  		return -ENOMEM;
  	}
  
  	dev_dbg(&dev->dev, "Allocated space for %u keycode entries (%u bytes)\n",
  		rc_map->size, rc_map->alloc);
  	return 0;
  }
  
  /**
   * ir_free_table() - frees memory allocated by a scancode table
   * @rc_map:	the table whose mappings need to be freed
   *
   * This routine will free memory alloctaed for key mappings used by given
   * scancode table.
   */
  static void ir_free_table(struct rc_map *rc_map)
  {
  	rc_map->size = 0;
  	kfree(rc_map->name);
  	rc_map->name = NULL;
  	kfree(rc_map->scan);
  	rc_map->scan = NULL;
  }
  
  /**
   * ir_resize_table() - resizes a scancode table if necessary
   * @dev:	the rc_dev device
   * @rc_map:	the rc_map to resize
   * @gfp_flags:	gfp flags to use when allocating memory
   *
   * This routine will shrink the rc_map if it has lots of
   * unused entries and grow it if it is full.
   *
   * return:	zero on success or a negative error code
   */
  static int ir_resize_table(struct rc_dev *dev, struct rc_map *rc_map,
  			   gfp_t gfp_flags)
  {
  	unsigned int oldalloc = rc_map->alloc;
  	unsigned int newalloc = oldalloc;
  	struct rc_map_table *oldscan = rc_map->scan;
  	struct rc_map_table *newscan;
  
  	if (rc_map->size == rc_map->len) {
  		/* All entries in use -> grow keytable */
  		if (rc_map->alloc >= IR_TAB_MAX_SIZE)
  			return -ENOMEM;
  
  		newalloc *= 2;
  		dev_dbg(&dev->dev, "Growing table to %u bytes\n", newalloc);
  	}
  
  	if ((rc_map->len * 3 < rc_map->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
  		/* Less than 1/3 of entries in use -> shrink keytable */
  		newalloc /= 2;
  		dev_dbg(&dev->dev, "Shrinking table to %u bytes\n", newalloc);
  	}
  
  	if (newalloc == oldalloc)
  		return 0;
  
  	newscan = kmalloc(newalloc, gfp_flags);
  	if (!newscan)
  		return -ENOMEM;
  
  	memcpy(newscan, rc_map->scan, rc_map->len * sizeof(struct rc_map_table));
  	rc_map->scan = newscan;
  	rc_map->alloc = newalloc;
  	rc_map->size = rc_map->alloc / sizeof(struct rc_map_table);
  	kfree(oldscan);
  	return 0;
  }
  
  /**
   * ir_update_mapping() - set a keycode in the scancode->keycode table
   * @dev:	the struct rc_dev device descriptor
   * @rc_map:	scancode table to be adjusted
   * @index:	index of the mapping that needs to be updated
   * @new_keycode: the desired keycode
   *
   * This routine is used to update scancode->keycode mapping at given
   * position.
   *
   * return:	previous keycode assigned to the mapping
   *
   */
  static unsigned int ir_update_mapping(struct rc_dev *dev,
  				      struct rc_map *rc_map,
  				      unsigned int index,
  				      unsigned int new_keycode)
  {
  	int old_keycode = rc_map->scan[index].keycode;
  
  	/* Did the user wish to remove the mapping? */
  	if (new_keycode == KEY_RESERVED || new_keycode == KEY_UNKNOWN) {
  		dev_dbg(&dev->dev, "#%d: Deleting scan 0x%04x\n",
  			index, rc_map->scan[index].scancode);
  		rc_map->len--;
  		memmove(&rc_map->scan[index], &rc_map->scan[index+ 1],
  			(rc_map->len - index) * sizeof(struct rc_map_table));
  	} else {
  		dev_dbg(&dev->dev, "#%d: %s scan 0x%04x with key 0x%04x\n",
  			index,
  			old_keycode == KEY_RESERVED ? "New" : "Replacing",
  			rc_map->scan[index].scancode, new_keycode);
  		rc_map->scan[index].keycode = new_keycode;
  	}
  
  	if (old_keycode != KEY_RESERVED) {
  		/* Possibly shrink the keytable, failure is not a problem */
  		ir_resize_table(dev, rc_map, GFP_ATOMIC);
  	}
  
  	return old_keycode;
  }
  
  /**
   * ir_establish_scancode() - set a keycode in the scancode->keycode table
   * @dev:	the struct rc_dev device descriptor
   * @rc_map:	scancode table to be searched
   * @scancode:	the desired scancode
   * @resize:	controls whether we allowed to resize the table to
   *		accommodate not yet present scancodes
   *
   * This routine is used to locate given scancode in rc_map.
   * If scancode is not yet present the routine will allocate a new slot
   * for it.
   *
   * return:	index of the mapping containing scancode in question
   *		or -1U in case of failure.
   */
  static unsigned int ir_establish_scancode(struct rc_dev *dev,
  					  struct rc_map *rc_map,
  					  unsigned int scancode,
  					  bool resize)
  {
  	unsigned int i;
  
  	/*
  	 * Unfortunately, some hardware-based IR decoders don't provide
  	 * all bits for the complete IR code. In general, they provide only
  	 * the command part of the IR code. Yet, as it is possible to replace
  	 * the provided IR with another one, it is needed to allow loading
  	 * IR tables from other remotes. So, we support specifying a mask to
  	 * indicate the valid bits of the scancodes.
  	 */
  	if (dev->scancode_mask)
  		scancode &= dev->scancode_mask;
  
  	/* First check if we already have a mapping for this ir command */
  	for (i = 0; i < rc_map->len; i++) {
  		if (rc_map->scan[i].scancode == scancode)
  			return i;
  
  		/* Keytable is sorted from lowest to highest scancode */
  		if (rc_map->scan[i].scancode >= scancode)
  			break;
  	}
  
  	/* No previous mapping found, we might need to grow the table */
  	if (rc_map->size == rc_map->len) {
  		if (!resize || ir_resize_table(dev, rc_map, GFP_ATOMIC))
  			return -1U;
  	}
  
  	/* i is the proper index to insert our new keycode */
  	if (i < rc_map->len)
  		memmove(&rc_map->scan[i + 1], &rc_map->scan[i],
  			(rc_map->len - i) * sizeof(struct rc_map_table));
  	rc_map->scan[i].scancode = scancode;
  	rc_map->scan[i].keycode = KEY_RESERVED;
  	rc_map->len++;
  
  	return i;
  }
  
  /**
   * ir_setkeycode() - set a keycode in the scancode->keycode table
   * @idev:	the struct input_dev device descriptor
   * @ke:		Input keymap entry
   * @old_keycode: result
   *
   * This routine is used to handle evdev EVIOCSKEY ioctl.
   *
   * return:	-EINVAL if the keycode could not be inserted, otherwise zero.
   */
  static int ir_setkeycode(struct input_dev *idev,
  			 const struct input_keymap_entry *ke,
  			 unsigned int *old_keycode)
  {
  	struct rc_dev *rdev = input_get_drvdata(idev);
  	struct rc_map *rc_map = &rdev->rc_map;
  	unsigned int index;
  	unsigned int scancode;
  	int retval = 0;
  	unsigned long flags;
  
  	spin_lock_irqsave(&rc_map->lock, flags);
  
  	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
  		index = ke->index;
  		if (index >= rc_map->len) {
  			retval = -EINVAL;
  			goto out;
  		}
  	} else {
  		retval = input_scancode_to_scalar(ke, &scancode);
  		if (retval)
  			goto out;
  
  		index = ir_establish_scancode(rdev, rc_map, scancode, true);
  		if (index >= rc_map->len) {
  			retval = -ENOMEM;
  			goto out;
  		}
  	}
  
  	*old_keycode = ir_update_mapping(rdev, rc_map, index, ke->keycode);
  
  out:
  	spin_unlock_irqrestore(&rc_map->lock, flags);
  	return retval;
  }
  
  /**
   * ir_setkeytable() - sets several entries in the scancode->keycode table
   * @dev:	the struct rc_dev device descriptor
   * @from:	the struct rc_map to copy entries from
   *
   * This routine is used to handle table initialization.
   *
   * return:	-ENOMEM if all keycodes could not be inserted, otherwise zero.
   */
  static int ir_setkeytable(struct rc_dev *dev,
  			  const struct rc_map *from)
  {
  	struct rc_map *rc_map = &dev->rc_map;
  	unsigned int i, index;
  	int rc;
  
  	rc = ir_create_table(dev, rc_map, from->name, from->rc_proto,
  			     from->size);
  	if (rc)
  		return rc;
  
  	for (i = 0; i < from->size; i++) {
  		index = ir_establish_scancode(dev, rc_map,
  					      from->scan[i].scancode, false);
  		if (index >= rc_map->len) {
  			rc = -ENOMEM;
  			break;
  		}
  
  		ir_update_mapping(dev, rc_map, index,
  				  from->scan[i].keycode);
  	}
  
  	if (rc)
  		ir_free_table(rc_map);
  
  	return rc;
  }
  
  static int rc_map_cmp(const void *key, const void *elt)
  {
  	const unsigned int *scancode = key;
  	const struct rc_map_table *e = elt;
  
  	if (*scancode < e->scancode)
  		return -1;
  	else if (*scancode > e->scancode)
  		return 1;
  	return 0;
  }
  
  /**
   * ir_lookup_by_scancode() - locate mapping by scancode
   * @rc_map:	the struct rc_map to search
   * @scancode:	scancode to look for in the table
   *
   * This routine performs binary search in RC keykeymap table for
   * given scancode.
   *
   * return:	index in the table, -1U if not found
   */
  static unsigned int ir_lookup_by_scancode(const struct rc_map *rc_map,
  					  unsigned int scancode)
  {
  	struct rc_map_table *res;
  
  	res = bsearch(&scancode, rc_map->scan, rc_map->len,
  		      sizeof(struct rc_map_table), rc_map_cmp);
  	if (!res)
  		return -1U;
  	else
  		return res - rc_map->scan;
  }
  
  /**
   * ir_getkeycode() - get a keycode from the scancode->keycode table
   * @idev:	the struct input_dev device descriptor
   * @ke:		Input keymap entry
   *
   * This routine is used to handle evdev EVIOCGKEY ioctl.
   *
   * return:	always returns zero.
   */
  static int ir_getkeycode(struct input_dev *idev,
  			 struct input_keymap_entry *ke)
  {
  	struct rc_dev *rdev = input_get_drvdata(idev);
  	struct rc_map *rc_map = &rdev->rc_map;
  	struct rc_map_table *entry;
  	unsigned long flags;
  	unsigned int index;
  	unsigned int scancode;
  	int retval;
  
  	spin_lock_irqsave(&rc_map->lock, flags);
  
  	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
  		index = ke->index;
  	} else {
  		retval = input_scancode_to_scalar(ke, &scancode);
  		if (retval)
  			goto out;
  
  		index = ir_lookup_by_scancode(rc_map, scancode);
  	}
  
  	if (index < rc_map->len) {
  		entry = &rc_map->scan[index];
  
  		ke->index = index;
  		ke->keycode = entry->keycode;
  		ke->len = sizeof(entry->scancode);
  		memcpy(ke->scancode, &entry->scancode, sizeof(entry->scancode));
  
  	} else if (!(ke->flags & INPUT_KEYMAP_BY_INDEX)) {
  		/*
  		 * We do not really know the valid range of scancodes
  		 * so let's respond with KEY_RESERVED to anything we
  		 * do not have mapping for [yet].
  		 */
  		ke->index = index;
  		ke->keycode = KEY_RESERVED;
  	} else {
  		retval = -EINVAL;
  		goto out;
  	}
  
  	retval = 0;
  
  out:
  	spin_unlock_irqrestore(&rc_map->lock, flags);
  	return retval;
  }
  
  /**
   * rc_g_keycode_from_table() - gets the keycode that corresponds to a scancode
   * @dev:	the struct rc_dev descriptor of the device
   * @scancode:	the scancode to look for
   *
   * This routine is used by drivers which need to convert a scancode to a
   * keycode. Normally it should not be used since drivers should have no
   * interest in keycodes.
   *
   * return:	the corresponding keycode, or KEY_RESERVED
   */
  u32 rc_g_keycode_from_table(struct rc_dev *dev, u32 scancode)
  {
  	struct rc_map *rc_map = &dev->rc_map;
  	unsigned int keycode;
  	unsigned int index;
  	unsigned long flags;
  
  	spin_lock_irqsave(&rc_map->lock, flags);
  
  	index = ir_lookup_by_scancode(rc_map, scancode);
  	keycode = index < rc_map->len ?
  			rc_map->scan[index].keycode : KEY_RESERVED;
  
  	spin_unlock_irqrestore(&rc_map->lock, flags);
  
  	if (keycode != KEY_RESERVED)
  		dev_dbg(&dev->dev, "%s: scancode 0x%04x keycode 0x%02x\n",
  			dev->device_name, scancode, keycode);
  
  	return keycode;
  }
  EXPORT_SYMBOL_GPL(rc_g_keycode_from_table);
  
  /**
   * ir_do_keyup() - internal function to signal the release of a keypress
   * @dev:	the struct rc_dev descriptor of the device
   * @sync:	whether or not to call input_sync
   *
   * This function is used internally to release a keypress, it must be
   * called with keylock held.
   */
  static void ir_do_keyup(struct rc_dev *dev, bool sync)
  {
  	if (!dev->keypressed)
  		return;
  
  	dev_dbg(&dev->dev, "keyup key 0x%04x\n", dev->last_keycode);
  	del_timer(&dev->timer_repeat);
  	input_report_key(dev->input_dev, dev->last_keycode, 0);
  	led_trigger_event(led_feedback, LED_OFF);
  	if (sync)
  		input_sync(dev->input_dev);
  	dev->keypressed = false;
  }
  
  /**
   * rc_keyup() - signals the release of a keypress
   * @dev:	the struct rc_dev descriptor of the device
   *
   * This routine is used to signal that a key has been released on the
   * remote control.
   */
  void rc_keyup(struct rc_dev *dev)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&dev->keylock, flags);
  	ir_do_keyup(dev, true);
  	spin_unlock_irqrestore(&dev->keylock, flags);
  }
  EXPORT_SYMBOL_GPL(rc_keyup);
  
  /**
   * ir_timer_keyup() - generates a keyup event after a timeout
   *
   * @t:		a pointer to the struct timer_list
   *
   * This routine will generate a keyup event some time after a keydown event
   * is generated when no further activity has been detected.
   */
  static void ir_timer_keyup(struct timer_list *t)
  {
  	struct rc_dev *dev = from_timer(dev, t, timer_keyup);
  	unsigned long flags;
  
  	/*
  	 * ir->keyup_jiffies is used to prevent a race condition if a
  	 * hardware interrupt occurs at this point and the keyup timer
  	 * event is moved further into the future as a result.
  	 *
  	 * The timer will then be reactivated and this function called
  	 * again in the future. We need to exit gracefully in that case
  	 * to allow the input subsystem to do its auto-repeat magic or
  	 * a keyup event might follow immediately after the keydown.
  	 */
  	spin_lock_irqsave(&dev->keylock, flags);
  	if (time_is_before_eq_jiffies(dev->keyup_jiffies))
  		ir_do_keyup(dev, true);
  	spin_unlock_irqrestore(&dev->keylock, flags);
  }
  
  /**
   * ir_timer_repeat() - generates a repeat event after a timeout
   *
   * @t:		a pointer to the struct timer_list
   *
   * This routine will generate a soft repeat event every REP_PERIOD
   * milliseconds.
   */
  static void ir_timer_repeat(struct timer_list *t)
  {
  	struct rc_dev *dev = from_timer(dev, t, timer_repeat);
  	struct input_dev *input = dev->input_dev;
  	unsigned long flags;
  
  	spin_lock_irqsave(&dev->keylock, flags);
  	if (dev->keypressed) {
  		input_event(input, EV_KEY, dev->last_keycode, 2);
  		input_sync(input);
  		if (input->rep[REP_PERIOD])
  			mod_timer(&dev->timer_repeat, jiffies +
  				  msecs_to_jiffies(input->rep[REP_PERIOD]));
  	}
  	spin_unlock_irqrestore(&dev->keylock, flags);
  }
  
  static unsigned int repeat_period(int protocol)
  {
  	if (protocol >= ARRAY_SIZE(protocols))
  		return 100;
  
  	return protocols[protocol].repeat_period;
  }
  
  /**
   * rc_repeat() - signals that a key is still pressed
   * @dev:	the struct rc_dev descriptor of the device
   *
   * This routine is used by IR decoders when a repeat message which does
   * not include the necessary bits to reproduce the scancode has been
   * received.
   */
  void rc_repeat(struct rc_dev *dev)
  {
  	unsigned long flags;
  	unsigned int timeout = nsecs_to_jiffies(dev->timeout) +
  		msecs_to_jiffies(repeat_period(dev->last_protocol));
  	struct lirc_scancode sc = {
  		.scancode = dev->last_scancode, .rc_proto = dev->last_protocol,
  		.keycode = dev->keypressed ? dev->last_keycode : KEY_RESERVED,
  		.flags = LIRC_SCANCODE_FLAG_REPEAT |
  			 (dev->last_toggle ? LIRC_SCANCODE_FLAG_TOGGLE : 0)
  	};
  
  	if (dev->allowed_protocols != RC_PROTO_BIT_CEC)
  		ir_lirc_scancode_event(dev, &sc);
  
  	spin_lock_irqsave(&dev->keylock, flags);
  
  	input_event(dev->input_dev, EV_MSC, MSC_SCAN, dev->last_scancode);
  	input_sync(dev->input_dev);
  
  	if (dev->keypressed) {
  		dev->keyup_jiffies = jiffies + timeout;
  		mod_timer(&dev->timer_keyup, dev->keyup_jiffies);
  	}
  
  	spin_unlock_irqrestore(&dev->keylock, flags);
  }
  EXPORT_SYMBOL_GPL(rc_repeat);
  
  /**
   * ir_do_keydown() - internal function to process a keypress
   * @dev:	the struct rc_dev descriptor of the device
   * @protocol:	the protocol of the keypress
   * @scancode:   the scancode of the keypress
   * @keycode:    the keycode of the keypress
   * @toggle:     the toggle value of the keypress
   *
   * This function is used internally to register a keypress, it must be
   * called with keylock held.
   */
  static void ir_do_keydown(struct rc_dev *dev, enum rc_proto protocol,
  			  u32 scancode, u32 keycode, u8 toggle)
  {
  	bool new_event = (!dev->keypressed		 ||
  			  dev->last_protocol != protocol ||
  			  dev->last_scancode != scancode ||
  			  dev->last_toggle   != toggle);
  	struct lirc_scancode sc = {
  		.scancode = scancode, .rc_proto = protocol,
  		.flags = toggle ? LIRC_SCANCODE_FLAG_TOGGLE : 0,
  		.keycode = keycode
  	};
  
  	if (dev->allowed_protocols != RC_PROTO_BIT_CEC)
  		ir_lirc_scancode_event(dev, &sc);
  
  	if (new_event && dev->keypressed)
  		ir_do_keyup(dev, false);
  
  	input_event(dev->input_dev, EV_MSC, MSC_SCAN, scancode);
  
  	dev->last_protocol = protocol;
  	dev->last_scancode = scancode;
  	dev->last_toggle = toggle;
  	dev->last_keycode = keycode;
  
  	if (new_event && keycode != KEY_RESERVED) {
  		/* Register a keypress */
  		dev->keypressed = true;
  
  		dev_dbg(&dev->dev, "%s: key down event, key 0x%04x, protocol 0x%04x, scancode 0x%08x\n",
  			dev->device_name, keycode, protocol, scancode);
  		input_report_key(dev->input_dev, keycode, 1);
  
  		led_trigger_event(led_feedback, LED_FULL);
  	}
  
  	/*
  	 * For CEC, start sending repeat messages as soon as the first
  	 * repeated message is sent, as long as REP_DELAY = 0 and REP_PERIOD
  	 * is non-zero. Otherwise, the input layer will generate repeat
  	 * messages.
  	 */
  	if (!new_event && keycode != KEY_RESERVED &&
  	    dev->allowed_protocols == RC_PROTO_BIT_CEC &&
  	    !timer_pending(&dev->timer_repeat) &&
  	    dev->input_dev->rep[REP_PERIOD] &&
  	    !dev->input_dev->rep[REP_DELAY]) {
  		input_event(dev->input_dev, EV_KEY, keycode, 2);
  		mod_timer(&dev->timer_repeat, jiffies +
  			  msecs_to_jiffies(dev->input_dev->rep[REP_PERIOD]));
  	}
  
  	input_sync(dev->input_dev);
  }
  
  /**
   * rc_keydown() - generates input event for a key press
   * @dev:	the struct rc_dev descriptor of the device
   * @protocol:	the protocol for the keypress
   * @scancode:	the scancode for the keypress
   * @toggle:     the toggle value (protocol dependent, if the protocol doesn't
   *              support toggle values, this should be set to zero)
   *
   * This routine is used to signal that a key has been pressed on the
   * remote control.
   */
  void rc_keydown(struct rc_dev *dev, enum rc_proto protocol, u32 scancode,
  		u8 toggle)
  {
  	unsigned long flags;
  	u32 keycode = rc_g_keycode_from_table(dev, scancode);
  
  	spin_lock_irqsave(&dev->keylock, flags);
  	ir_do_keydown(dev, protocol, scancode, keycode, toggle);
  
  	if (dev->keypressed) {
  		dev->keyup_jiffies = jiffies + nsecs_to_jiffies(dev->timeout) +
  			msecs_to_jiffies(repeat_period(protocol));
  		mod_timer(&dev->timer_keyup, dev->keyup_jiffies);
  	}
  	spin_unlock_irqrestore(&dev->keylock, flags);
  }
  EXPORT_SYMBOL_GPL(rc_keydown);
  
  /**
   * rc_keydown_notimeout() - generates input event for a key press without
   *                          an automatic keyup event at a later time
   * @dev:	the struct rc_dev descriptor of the device
   * @protocol:	the protocol for the keypress
   * @scancode:	the scancode for the keypress
   * @toggle:     the toggle value (protocol dependent, if the protocol doesn't
   *              support toggle values, this should be set to zero)
   *
   * This routine is used to signal that a key has been pressed on the
   * remote control. The driver must manually call rc_keyup() at a later stage.
   */
  void rc_keydown_notimeout(struct rc_dev *dev, enum rc_proto protocol,
  			  u32 scancode, u8 toggle)
  {
  	unsigned long flags;
  	u32 keycode = rc_g_keycode_from_table(dev, scancode);
  
  	spin_lock_irqsave(&dev->keylock, flags);
  	ir_do_keydown(dev, protocol, scancode, keycode, toggle);
  	spin_unlock_irqrestore(&dev->keylock, flags);
  }
  EXPORT_SYMBOL_GPL(rc_keydown_notimeout);
  
  /**
   * rc_validate_scancode() - checks that a scancode is valid for a protocol.
   *	For nec, it should do the opposite of ir_nec_bytes_to_scancode()
   * @proto:	protocol
   * @scancode:	scancode
   */
  bool rc_validate_scancode(enum rc_proto proto, u32 scancode)
  {
  	switch (proto) {
  	/*
  	 * NECX has a 16-bit address; if the lower 8 bits match the upper
  	 * 8 bits inverted, then the address would match regular nec.
  	 */
  	case RC_PROTO_NECX:
  		if ((((scancode >> 16) ^ ~(scancode >> 8)) & 0xff) == 0)
  			return false;
  		break;
  	/*
  	 * NEC32 has a 16 bit address and 16 bit command. If the lower 8 bits
  	 * of the command match the upper 8 bits inverted, then it would
  	 * be either NEC or NECX.
  	 */
  	case RC_PROTO_NEC32:
  		if ((((scancode >> 8) ^ ~scancode) & 0xff) == 0)
  			return false;
  		break;
  	/*
  	 * If the customer code (top 32-bit) is 0x800f, it is MCE else it
  	 * is regular mode-6a 32 bit
  	 */
  	case RC_PROTO_RC6_MCE:
  		if ((scancode & 0xffff0000) != 0x800f0000)
  			return false;
  		break;
  	case RC_PROTO_RC6_6A_32:
  		if ((scancode & 0xffff0000) == 0x800f0000)
  			return false;
  		break;
  	default:
  		break;
  	}
  
  	return true;
  }
  
  /**
   * rc_validate_filter() - checks that the scancode and mask are valid and
   *			  provides sensible defaults
   * @dev:	the struct rc_dev descriptor of the device
   * @filter:	the scancode and mask
   *
   * return:	0 or -EINVAL if the filter is not valid
   */
  static int rc_validate_filter(struct rc_dev *dev,
  			      struct rc_scancode_filter *filter)
  {
  	u32 mask, s = filter->data;
  	enum rc_proto protocol = dev->wakeup_protocol;
  
  	if (protocol >= ARRAY_SIZE(protocols))
  		return -EINVAL;
  
  	mask = protocols[protocol].scancode_bits;
  
  	if (!rc_validate_scancode(protocol, s))
  		return -EINVAL;
  
  	filter->data &= mask;
  	filter->mask &= mask;
  
  	/*
  	 * If we have to raw encode the IR for wakeup, we cannot have a mask
  	 */
  	if (dev->encode_wakeup && filter->mask != 0 && filter->mask != mask)
  		return -EINVAL;
  
  	return 0;
  }
  
  int rc_open(struct rc_dev *rdev)
  {
  	int rval = 0;
  
  	if (!rdev)
  		return -EINVAL;
  
  	mutex_lock(&rdev->lock);
  
  	if (!rdev->registered) {
  		rval = -ENODEV;
  	} else {
  		if (!rdev->users++ && rdev->open)
  			rval = rdev->open(rdev);
  
  		if (rval)
  			rdev->users--;
  	}
  
  	mutex_unlock(&rdev->lock);
  
  	return rval;
  }
  
  static int ir_open(struct input_dev *idev)
  {
  	struct rc_dev *rdev = input_get_drvdata(idev);
  
  	return rc_open(rdev);
  }
  
  void rc_close(struct rc_dev *rdev)
  {
  	if (rdev) {
  		mutex_lock(&rdev->lock);
  
  		if (!--rdev->users && rdev->close && rdev->registered)
  			rdev->close(rdev);
  
  		mutex_unlock(&rdev->lock);
  	}
  }
  
  static void ir_close(struct input_dev *idev)
  {
  	struct rc_dev *rdev = input_get_drvdata(idev);
  	rc_close(rdev);
  }
  
  /* class for /sys/class/rc */
  static char *rc_devnode(struct device *dev, umode_t *mode)
  {
  	return kasprintf(GFP_KERNEL, "rc/%s", dev_name(dev));
  }
  
  static struct class rc_class = {
  	.name		= "rc",
  	.devnode	= rc_devnode,
  };
  
  /*
   * These are the protocol textual descriptions that are
   * used by the sysfs protocols file. Note that the order
   * of the entries is relevant.
   */
  static const struct {
  	u64	type;
  	const char	*name;
  	const char	*module_name;
  } proto_names[] = {
  	{ RC_PROTO_BIT_NONE,	"none",		NULL			},
  	{ RC_PROTO_BIT_OTHER,	"other",	NULL			},
  	{ RC_PROTO_BIT_UNKNOWN,	"unknown",	NULL			},
  	{ RC_PROTO_BIT_RC5 |
  	  RC_PROTO_BIT_RC5X_20,	"rc-5",		"ir-rc5-decoder"	},
  	{ RC_PROTO_BIT_NEC |
  	  RC_PROTO_BIT_NECX |
  	  RC_PROTO_BIT_NEC32,	"nec",		"ir-nec-decoder"	},
  	{ RC_PROTO_BIT_RC6_0 |
  	  RC_PROTO_BIT_RC6_6A_20 |
  	  RC_PROTO_BIT_RC6_6A_24 |
  	  RC_PROTO_BIT_RC6_6A_32 |
  	  RC_PROTO_BIT_RC6_MCE,	"rc-6",		"ir-rc6-decoder"	},
  	{ RC_PROTO_BIT_JVC,	"jvc",		"ir-jvc-decoder"	},
  	{ RC_PROTO_BIT_SONY12 |
  	  RC_PROTO_BIT_SONY15 |
  	  RC_PROTO_BIT_SONY20,	"sony",		"ir-sony-decoder"	},
  	{ RC_PROTO_BIT_RC5_SZ,	"rc-5-sz",	"ir-rc5-decoder"	},
  	{ RC_PROTO_BIT_SANYO,	"sanyo",	"ir-sanyo-decoder"	},
  	{ RC_PROTO_BIT_SHARP,	"sharp",	"ir-sharp-decoder"	},
  	{ RC_PROTO_BIT_MCIR2_KBD |
  	  RC_PROTO_BIT_MCIR2_MSE, "mce_kbd",	"ir-mce_kbd-decoder"	},
  	{ RC_PROTO_BIT_XMP,	"xmp",		"ir-xmp-decoder"	},
  	{ RC_PROTO_BIT_CEC,	"cec",		NULL			},
  	{ RC_PROTO_BIT_IMON,	"imon",		"ir-imon-decoder"	},
  };
  
  /**
   * struct rc_filter_attribute - Device attribute relating to a filter type.
   * @attr:	Device attribute.
   * @type:	Filter type.
   * @mask:	false for filter value, true for filter mask.
   */
  struct rc_filter_attribute {
  	struct device_attribute		attr;
  	enum rc_filter_type		type;
  	bool				mask;
  };
  #define to_rc_filter_attr(a) container_of(a, struct rc_filter_attribute, attr)
  
  #define RC_FILTER_ATTR(_name, _mode, _show, _store, _type, _mask)	\
  	struct rc_filter_attribute dev_attr_##_name = {			\
  		.attr = __ATTR(_name, _mode, _show, _store),		\
  		.type = (_type),					\
  		.mask = (_mask),					\
  	}
  
  /**
   * show_protocols() - shows the current IR protocol(s)
   * @device:	the device descriptor
   * @mattr:	the device attribute struct
   * @buf:	a pointer to the output buffer
   *
   * This routine is a callback routine for input read the IR protocol type(s).
   * it is trigged by reading /sys/class/rc/rc?/protocols.
   * It returns the protocol names of supported protocols.
   * Enabled protocols are printed in brackets.
   *
   * dev->lock is taken to guard against races between
   * store_protocols and show_protocols.
   */
  static ssize_t show_protocols(struct device *device,
  			      struct device_attribute *mattr, char *buf)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  	u64 allowed, enabled;
  	char *tmp = buf;
  	int i;
  
  	mutex_lock(&dev->lock);
  
  	enabled = dev->enabled_protocols;
  	allowed = dev->allowed_protocols;
  	if (dev->raw && !allowed)
  		allowed = ir_raw_get_allowed_protocols();
  
  	mutex_unlock(&dev->lock);
  
  	dev_dbg(&dev->dev, "%s: allowed - 0x%llx, enabled - 0x%llx\n",
  		__func__, (long long)allowed, (long long)enabled);
  
  	for (i = 0; i < ARRAY_SIZE(proto_names); i++) {
  		if (allowed & enabled & proto_names[i].type)
  			tmp += sprintf(tmp, "[%s] ", proto_names[i].name);
  		else if (allowed & proto_names[i].type)
  			tmp += sprintf(tmp, "%s ", proto_names[i].name);
  
  		if (allowed & proto_names[i].type)
  			allowed &= ~proto_names[i].type;
  	}
  
  #ifdef CONFIG_LIRC
  	if (dev->driver_type == RC_DRIVER_IR_RAW)
  		tmp += sprintf(tmp, "[lirc] ");
  #endif
  
  	if (tmp != buf)
  		tmp--;
  	*tmp = '\n';
  
  	return tmp + 1 - buf;
  }
  
  /**
   * parse_protocol_change() - parses a protocol change request
   * @dev:	rc_dev device
   * @protocols:	pointer to the bitmask of current protocols
   * @buf:	pointer to the buffer with a list of changes
   *
   * Writing "+proto" will add a protocol to the protocol mask.
   * Writing "-proto" will remove a protocol from protocol mask.
   * Writing "proto" will enable only "proto".
   * Writing "none" will disable all protocols.
   * Returns the number of changes performed or a negative error code.
   */
  static int parse_protocol_change(struct rc_dev *dev, u64 *protocols,
  				 const char *buf)
  {
  	const char *tmp;
  	unsigned count = 0;
  	bool enable, disable;
  	u64 mask;
  	int i;
  
  	while ((tmp = strsep((char **)&buf, " \n")) != NULL) {
  		if (!*tmp)
  			break;
  
  		if (*tmp == '+') {
  			enable = true;
  			disable = false;
  			tmp++;
  		} else if (*tmp == '-') {
  			enable = false;
  			disable = true;
  			tmp++;
  		} else {
  			enable = false;
  			disable = false;
  		}
  
  		for (i = 0; i < ARRAY_SIZE(proto_names); i++) {
  			if (!strcasecmp(tmp, proto_names[i].name)) {
  				mask = proto_names[i].type;
  				break;
  			}
  		}
  
  		if (i == ARRAY_SIZE(proto_names)) {
  			if (!strcasecmp(tmp, "lirc"))
  				mask = 0;
  			else {
  				dev_dbg(&dev->dev, "Unknown protocol: '%s'\n",
  					tmp);
  				return -EINVAL;
  			}
  		}
  
  		count++;
  
  		if (enable)
  			*protocols |= mask;
  		else if (disable)
  			*protocols &= ~mask;
  		else
  			*protocols = mask;
  	}
  
  	if (!count) {
  		dev_dbg(&dev->dev, "Protocol not specified\n");
  		return -EINVAL;
  	}
  
  	return count;
  }
  
  void ir_raw_load_modules(u64 *protocols)
  {
  	u64 available;
  	int i, ret;
  
  	for (i = 0; i < ARRAY_SIZE(proto_names); i++) {
  		if (proto_names[i].type == RC_PROTO_BIT_NONE ||
  		    proto_names[i].type & (RC_PROTO_BIT_OTHER |
  					   RC_PROTO_BIT_UNKNOWN))
  			continue;
  
  		available = ir_raw_get_allowed_protocols();
  		if (!(*protocols & proto_names[i].type & ~available))
  			continue;
  
  		if (!proto_names[i].module_name) {
  			pr_err("Can't enable IR protocol %s\n",
  			       proto_names[i].name);
  			*protocols &= ~proto_names[i].type;
  			continue;
  		}
  
  		ret = request_module("%s", proto_names[i].module_name);
  		if (ret < 0) {
  			pr_err("Couldn't load IR protocol module %s\n",
  			       proto_names[i].module_name);
  			*protocols &= ~proto_names[i].type;
  			continue;
  		}
  		msleep(20);
  		available = ir_raw_get_allowed_protocols();
  		if (!(*protocols & proto_names[i].type & ~available))
  			continue;
  
  		pr_err("Loaded IR protocol module %s, but protocol %s still not available\n",
  		       proto_names[i].module_name,
  		       proto_names[i].name);
  		*protocols &= ~proto_names[i].type;
  	}
  }
  
  /**
   * store_protocols() - changes the current/wakeup IR protocol(s)
   * @device:	the device descriptor
   * @mattr:	the device attribute struct
   * @buf:	a pointer to the input buffer
   * @len:	length of the input buffer
   *
   * This routine is for changing the IR protocol type.
   * It is trigged by writing to /sys/class/rc/rc?/[wakeup_]protocols.
   * See parse_protocol_change() for the valid commands.
   * Returns @len on success or a negative error code.
   *
   * dev->lock is taken to guard against races between
   * store_protocols and show_protocols.
   */
  static ssize_t store_protocols(struct device *device,
  			       struct device_attribute *mattr,
  			       const char *buf, size_t len)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  	u64 *current_protocols;
  	struct rc_scancode_filter *filter;
  	u64 old_protocols, new_protocols;
  	ssize_t rc;
  
  	dev_dbg(&dev->dev, "Normal protocol change requested\n");
  	current_protocols = &dev->enabled_protocols;
  	filter = &dev->scancode_filter;
  
  	if (!dev->change_protocol) {
  		dev_dbg(&dev->dev, "Protocol switching not supported\n");
  		return -EINVAL;
  	}
  
  	mutex_lock(&dev->lock);
  
  	old_protocols = *current_protocols;
  	new_protocols = old_protocols;
  	rc = parse_protocol_change(dev, &new_protocols, buf);
  	if (rc < 0)
  		goto out;
  
  	if (dev->driver_type == RC_DRIVER_IR_RAW)
  		ir_raw_load_modules(&new_protocols);
  
  	rc = dev->change_protocol(dev, &new_protocols);
  	if (rc < 0) {
  		dev_dbg(&dev->dev, "Error setting protocols to 0x%llx\n",
  			(long long)new_protocols);
  		goto out;
  	}
  
  	if (new_protocols != old_protocols) {
  		*current_protocols = new_protocols;
  		dev_dbg(&dev->dev, "Protocols changed to 0x%llx\n",
  			(long long)new_protocols);
  	}
  
  	/*
  	 * If a protocol change was attempted the filter may need updating, even
  	 * if the actual protocol mask hasn't changed (since the driver may have
  	 * cleared the filter).
  	 * Try setting the same filter with the new protocol (if any).
  	 * Fall back to clearing the filter.
  	 */
  	if (dev->s_filter && filter->mask) {
  		if (new_protocols)
  			rc = dev->s_filter(dev, filter);
  		else
  			rc = -1;
  
  		if (rc < 0) {
  			filter->data = 0;
  			filter->mask = 0;
  			dev->s_filter(dev, filter);
  		}
  	}
  
  	rc = len;
  
  out:
  	mutex_unlock(&dev->lock);
  	return rc;
  }
  
  /**
   * show_filter() - shows the current scancode filter value or mask
   * @device:	the device descriptor
   * @attr:	the device attribute struct
   * @buf:	a pointer to the output buffer
   *
   * This routine is a callback routine to read a scancode filter value or mask.
   * It is trigged by reading /sys/class/rc/rc?/[wakeup_]filter[_mask].
   * It prints the current scancode filter value or mask of the appropriate filter
   * type in hexadecimal into @buf and returns the size of the buffer.
   *
   * Bits of the filter value corresponding to set bits in the filter mask are
   * compared against input scancodes and non-matching scancodes are discarded.
   *
   * dev->lock is taken to guard against races between
   * store_filter and show_filter.
   */
  static ssize_t show_filter(struct device *device,
  			   struct device_attribute *attr,
  			   char *buf)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  	struct rc_filter_attribute *fattr = to_rc_filter_attr(attr);
  	struct rc_scancode_filter *filter;
  	u32 val;
  
  	mutex_lock(&dev->lock);
  
  	if (fattr->type == RC_FILTER_NORMAL)
  		filter = &dev->scancode_filter;
  	else
  		filter = &dev->scancode_wakeup_filter;
  
  	if (fattr->mask)
  		val = filter->mask;
  	else
  		val = filter->data;
  	mutex_unlock(&dev->lock);
  
  	return sprintf(buf, "%#x\n", val);
  }
  
  /**
   * store_filter() - changes the scancode filter value
   * @device:	the device descriptor
   * @attr:	the device attribute struct
   * @buf:	a pointer to the input buffer
   * @len:	length of the input buffer
   *
   * This routine is for changing a scancode filter value or mask.
   * It is trigged by writing to /sys/class/rc/rc?/[wakeup_]filter[_mask].
   * Returns -EINVAL if an invalid filter value for the current protocol was
   * specified or if scancode filtering is not supported by the driver, otherwise
   * returns @len.
   *
   * Bits of the filter value corresponding to set bits in the filter mask are
   * compared against input scancodes and non-matching scancodes are discarded.
   *
   * dev->lock is taken to guard against races between
   * store_filter and show_filter.
   */
  static ssize_t store_filter(struct device *device,
  			    struct device_attribute *attr,
  			    const char *buf, size_t len)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  	struct rc_filter_attribute *fattr = to_rc_filter_attr(attr);
  	struct rc_scancode_filter new_filter, *filter;
  	int ret;
  	unsigned long val;
  	int (*set_filter)(struct rc_dev *dev, struct rc_scancode_filter *filter);
  
  	ret = kstrtoul(buf, 0, &val);
  	if (ret < 0)
  		return ret;
  
  	if (fattr->type == RC_FILTER_NORMAL) {
  		set_filter = dev->s_filter;
  		filter = &dev->scancode_filter;
  	} else {
  		set_filter = dev->s_wakeup_filter;
  		filter = &dev->scancode_wakeup_filter;
  	}
  
  	if (!set_filter)
  		return -EINVAL;
  
  	mutex_lock(&dev->lock);
  
  	new_filter = *filter;
  	if (fattr->mask)
  		new_filter.mask = val;
  	else
  		new_filter.data = val;
  
  	if (fattr->type == RC_FILTER_WAKEUP) {
  		/*
  		 * Refuse to set a filter unless a protocol is enabled
  		 * and the filter is valid for that protocol
  		 */
  		if (dev->wakeup_protocol != RC_PROTO_UNKNOWN)
  			ret = rc_validate_filter(dev, &new_filter);
  		else
  			ret = -EINVAL;
  
  		if (ret != 0)
  			goto unlock;
  	}
  
  	if (fattr->type == RC_FILTER_NORMAL && !dev->enabled_protocols &&
  	    val) {
  		/* refuse to set a filter unless a protocol is enabled */
  		ret = -EINVAL;
  		goto unlock;
  	}
  
  	ret = set_filter(dev, &new_filter);
  	if (ret < 0)
  		goto unlock;
  
  	*filter = new_filter;
  
  unlock:
  	mutex_unlock(&dev->lock);
  	return (ret < 0) ? ret : len;
  }
  
  /**
   * show_wakeup_protocols() - shows the wakeup IR protocol
   * @device:	the device descriptor
   * @mattr:	the device attribute struct
   * @buf:	a pointer to the output buffer
   *
   * This routine is a callback routine for input read the IR protocol type(s).
   * it is trigged by reading /sys/class/rc/rc?/wakeup_protocols.
   * It returns the protocol names of supported protocols.
   * The enabled protocols are printed in brackets.
   *
   * dev->lock is taken to guard against races between
   * store_wakeup_protocols and show_wakeup_protocols.
   */
  static ssize_t show_wakeup_protocols(struct device *device,
  				     struct device_attribute *mattr,
  				     char *buf)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  	u64 allowed;
  	enum rc_proto enabled;
  	char *tmp = buf;
  	int i;
  
  	mutex_lock(&dev->lock);
  
  	allowed = dev->allowed_wakeup_protocols;
  	enabled = dev->wakeup_protocol;
  
  	mutex_unlock(&dev->lock);
  
  	dev_dbg(&dev->dev, "%s: allowed - 0x%llx, enabled - %d\n",
  		__func__, (long long)allowed, enabled);
  
  	for (i = 0; i < ARRAY_SIZE(protocols); i++) {
  		if (allowed & (1ULL << i)) {
  			if (i == enabled)
  				tmp += sprintf(tmp, "[%s] ", protocols[i].name);
  			else
  				tmp += sprintf(tmp, "%s ", protocols[i].name);
  		}
  	}
  
  	if (tmp != buf)
  		tmp--;
  	*tmp = '\n';
  
  	return tmp + 1 - buf;
  }
  
  /**
   * store_wakeup_protocols() - changes the wakeup IR protocol(s)
   * @device:	the device descriptor
   * @mattr:	the device attribute struct
   * @buf:	a pointer to the input buffer
   * @len:	length of the input buffer
   *
   * This routine is for changing the IR protocol type.
   * It is trigged by writing to /sys/class/rc/rc?/wakeup_protocols.
   * Returns @len on success or a negative error code.
   *
   * dev->lock is taken to guard against races between
   * store_wakeup_protocols and show_wakeup_protocols.
   */
  static ssize_t store_wakeup_protocols(struct device *device,
  				      struct device_attribute *mattr,
  				      const char *buf, size_t len)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  	enum rc_proto protocol;
  	ssize_t rc;
  	u64 allowed;
  	int i;
  
  	mutex_lock(&dev->lock);
  
  	allowed = dev->allowed_wakeup_protocols;
  
  	if (sysfs_streq(buf, "none")) {
  		protocol = RC_PROTO_UNKNOWN;
  	} else {
  		for (i = 0; i < ARRAY_SIZE(protocols); i++) {
  			if ((allowed & (1ULL << i)) &&
  			    sysfs_streq(buf, protocols[i].name)) {
  				protocol = i;
  				break;
  			}
  		}
  
  		if (i == ARRAY_SIZE(protocols)) {
  			rc = -EINVAL;
  			goto out;
  		}
  
  		if (dev->encode_wakeup) {
  			u64 mask = 1ULL << protocol;
  
  			ir_raw_load_modules(&mask);
  			if (!mask) {
  				rc = -EINVAL;
  				goto out;
  			}
  		}
  	}
  
  	if (dev->wakeup_protocol != protocol) {
  		dev->wakeup_protocol = protocol;
  		dev_dbg(&dev->dev, "Wakeup protocol changed to %d\n", protocol);
  
  		if (protocol == RC_PROTO_RC6_MCE)
  			dev->scancode_wakeup_filter.data = 0x800f0000;
  		else
  			dev->scancode_wakeup_filter.data = 0;
  		dev->scancode_wakeup_filter.mask = 0;
  
  		rc = dev->s_wakeup_filter(dev, &dev->scancode_wakeup_filter);
  		if (rc == 0)
  			rc = len;
  	} else {
  		rc = len;
  	}
  
  out:
  	mutex_unlock(&dev->lock);
  	return rc;
  }
  
  static void rc_dev_release(struct device *device)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  
  	kfree(dev);
  }
  
  #define ADD_HOTPLUG_VAR(fmt, val...)					\
  	do {								\
  		int err = add_uevent_var(env, fmt, val);		\
  		if (err)						\
  			return err;					\
  	} while (0)
  
  static int rc_dev_uevent(struct device *device, struct kobj_uevent_env *env)
  {
  	struct rc_dev *dev = to_rc_dev(device);
  
  	if (dev->rc_map.name)
  		ADD_HOTPLUG_VAR("NAME=%s", dev->rc_map.name);
  	if (dev->driver_name)
  		ADD_HOTPLUG_VAR("DRV_NAME=%s", dev->driver_name);
  	if (dev->device_name)
  		ADD_HOTPLUG_VAR("DEV_NAME=%s", dev->device_name);
  
  	return 0;
  }
  
  /*
   * Static device attribute struct with the sysfs attributes for IR's
   */
  static struct device_attribute dev_attr_ro_protocols =
  __ATTR(protocols, 0444, show_protocols, NULL);
  static struct device_attribute dev_attr_rw_protocols =
  __ATTR(protocols, 0644, show_protocols, store_protocols);
  static DEVICE_ATTR(wakeup_protocols, 0644, show_wakeup_protocols,
  		   store_wakeup_protocols);
  static RC_FILTER_ATTR(filter, S_IRUGO|S_IWUSR,
  		      show_filter, store_filter, RC_FILTER_NORMAL, false);
  static RC_FILTER_ATTR(filter_mask, S_IRUGO|S_IWUSR,
  		      show_filter, store_filter, RC_FILTER_NORMAL, true);
  static RC_FILTER_ATTR(wakeup_filter, S_IRUGO|S_IWUSR,
  		      show_filter, store_filter, RC_FILTER_WAKEUP, false);
  static RC_FILTER_ATTR(wakeup_filter_mask, S_IRUGO|S_IWUSR,
  		      show_filter, store_filter, RC_FILTER_WAKEUP, true);
  
  static struct attribute *rc_dev_rw_protocol_attrs[] = {
  	&dev_attr_rw_protocols.attr,
  	NULL,
  };
  
  static const struct attribute_group rc_dev_rw_protocol_attr_grp = {
  	.attrs	= rc_dev_rw_protocol_attrs,
  };
  
  static struct attribute *rc_dev_ro_protocol_attrs[] = {
  	&dev_attr_ro_protocols.attr,
  	NULL,
  };
  
  static const struct attribute_group rc_dev_ro_protocol_attr_grp = {
  	.attrs	= rc_dev_ro_protocol_attrs,
  };
  
  static struct attribute *rc_dev_filter_attrs[] = {
  	&dev_attr_filter.attr.attr,
  	&dev_attr_filter_mask.attr.attr,
  	NULL,
  };
  
  static const struct attribute_group rc_dev_filter_attr_grp = {
  	.attrs	= rc_dev_filter_attrs,
  };
  
  static struct attribute *rc_dev_wakeup_filter_attrs[] = {
  	&dev_attr_wakeup_filter.attr.attr,
  	&dev_attr_wakeup_filter_mask.attr.attr,
  	&dev_attr_wakeup_protocols.attr,
  	NULL,
  };
  
  static const struct attribute_group rc_dev_wakeup_filter_attr_grp = {
  	.attrs	= rc_dev_wakeup_filter_attrs,
  };
  
  static const struct device_type rc_dev_type = {
  	.release	= rc_dev_release,
  	.uevent		= rc_dev_uevent,
  };
  
  struct rc_dev *rc_allocate_device(enum rc_driver_type type)
  {
  	struct rc_dev *dev;
  
  	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
  	if (!dev)
  		return NULL;
  
  	if (type != RC_DRIVER_IR_RAW_TX) {
  		dev->input_dev = input_allocate_device();
  		if (!dev->input_dev) {
  			kfree(dev);
  			return NULL;
  		}
  
  		dev->input_dev->getkeycode = ir_getkeycode;
  		dev->input_dev->setkeycode = ir_setkeycode;
  		input_set_drvdata(dev->input_dev, dev);
  
  		dev->timeout = IR_DEFAULT_TIMEOUT;
  		timer_setup(&dev->timer_keyup, ir_timer_keyup, 0);
  		timer_setup(&dev->timer_repeat, ir_timer_repeat, 0);
  
  		spin_lock_init(&dev->rc_map.lock);
  		spin_lock_init(&dev->keylock);
  	}
  	mutex_init(&dev->lock);
  
  	dev->dev.type = &rc_dev_type;
  	dev->dev.class = &rc_class;
  	device_initialize(&dev->dev);
  
  	dev->driver_type = type;
  
  	__module_get(THIS_MODULE);
  	return dev;
  }
  EXPORT_SYMBOL_GPL(rc_allocate_device);
  
  void rc_free_device(struct rc_dev *dev)
  {
  	if (!dev)
  		return;
  
  	input_free_device(dev->input_dev);
  
  	put_device(&dev->dev);
  
  	/* kfree(dev) will be called by the callback function
  	   rc_dev_release() */
  
  	module_put(THIS_MODULE);
  }
  EXPORT_SYMBOL_GPL(rc_free_device);
  
  static void devm_rc_alloc_release(struct device *dev, void *res)
  {
  	rc_free_device(*(struct rc_dev **)res);
  }
  
  struct rc_dev *devm_rc_allocate_device(struct device *dev,
  				       enum rc_driver_type type)
  {
  	struct rc_dev **dr, *rc;
  
  	dr = devres_alloc(devm_rc_alloc_release, sizeof(*dr), GFP_KERNEL);
  	if (!dr)
  		return NULL;
  
  	rc = rc_allocate_device(type);
  	if (!rc) {
  		devres_free(dr);
  		return NULL;
  	}
  
  	rc->dev.parent = dev;
  	rc->managed_alloc = true;
  	*dr = rc;
  	devres_add(dev, dr);
  
  	return rc;
  }
  EXPORT_SYMBOL_GPL(devm_rc_allocate_device);
  
  static int rc_prepare_rx_device(struct rc_dev *dev)
  {
  	int rc;
  	struct rc_map *rc_map;
  	u64 rc_proto;
  
  	if (!dev->map_name)
  		return -EINVAL;
  
  	rc_map = rc_map_get(dev->map_name);
  	if (!rc_map)
  		rc_map = rc_map_get(RC_MAP_EMPTY);
  	if (!rc_map || !rc_map->scan || rc_map->size == 0)
  		return -EINVAL;
  
  	rc = ir_setkeytable(dev, rc_map);
  	if (rc)
  		return rc;
  
  	rc_proto = BIT_ULL(rc_map->rc_proto);
  
  	if (dev->driver_type == RC_DRIVER_SCANCODE && !dev->change_protocol)
  		dev->enabled_protocols = dev->allowed_protocols;
  
  	if (dev->driver_type == RC_DRIVER_IR_RAW)
  		ir_raw_load_modules(&rc_proto);
  
  	if (dev->change_protocol) {
  		rc = dev->change_protocol(dev, &rc_proto);
  		if (rc < 0)
  			goto out_table;
  		dev->enabled_protocols = rc_proto;
  	}
  
  	/* Keyboard events */
  	set_bit(EV_KEY, dev->input_dev->evbit);
  	set_bit(EV_REP, dev->input_dev->evbit);
  	set_bit(EV_MSC, dev->input_dev->evbit);
  	set_bit(MSC_SCAN, dev->input_dev->mscbit);
  	bitmap_fill(dev->input_dev->keybit, KEY_CNT);
  
  	/* Pointer/mouse events */
  	set_bit(EV_REL, dev->input_dev->evbit);
  	set_bit(REL_X, dev->input_dev->relbit);
  	set_bit(REL_Y, dev->input_dev->relbit);
  
  	if (dev->open)
  		dev->input_dev->open = ir_open;
  	if (dev->close)
  		dev->input_dev->close = ir_close;
  
  	dev->input_dev->dev.parent = &dev->dev;
  	memcpy(&dev->input_dev->id, &dev->input_id, sizeof(dev->input_id));
  	dev->input_dev->phys = dev->input_phys;
  	dev->input_dev->name = dev->device_name;
  
  	return 0;
  
  out_table:
  	ir_free_table(&dev->rc_map);
  
  	return rc;
  }
  
  static int rc_setup_rx_device(struct rc_dev *dev)
  {
  	int rc;
  
  	/* rc_open will be called here */
  	rc = input_register_device(dev->input_dev);
  	if (rc)
  		return rc;
  
  	/*
  	 * Default delay of 250ms is too short for some protocols, especially
  	 * since the timeout is currently set to 250ms. Increase it to 500ms,
  	 * to avoid wrong repetition of the keycodes. Note that this must be
  	 * set after the call to input_register_device().
  	 */
  	if (dev->allowed_protocols == RC_PROTO_BIT_CEC)
  		dev->input_dev->rep[REP_DELAY] = 0;
  	else
  		dev->input_dev->rep[REP_DELAY] = 500;
  
  	/*
  	 * As a repeat event on protocols like RC-5 and NEC take as long as
  	 * 110/114ms, using 33ms as a repeat period is not the right thing
  	 * to do.
  	 */
  	dev->input_dev->rep[REP_PERIOD] = 125;
  
  	return 0;
  }
  
  static void rc_free_rx_device(struct rc_dev *dev)
  {
  	if (!dev)
  		return;
  
  	if (dev->input_dev) {
  		input_unregister_device(dev->input_dev);
  		dev->input_dev = NULL;
  	}
  
  	ir_free_table(&dev->rc_map);
  }
  
  int rc_register_device(struct rc_dev *dev)
  {
  	const char *path;
  	int attr = 0;
  	int minor;
  	int rc;
  
  	if (!dev)
  		return -EINVAL;
  
  	minor = ida_simple_get(&rc_ida, 0, RC_DEV_MAX, GFP_KERNEL);
  	if (minor < 0)
  		return minor;
  
  	dev->minor = minor;
  	dev_set_name(&dev->dev, "rc%u", dev->minor);
  	dev_set_drvdata(&dev->dev, dev);
  
  	dev->dev.groups = dev->sysfs_groups;
  	if (dev->driver_type == RC_DRIVER_SCANCODE && !dev->change_protocol)
  		dev->sysfs_groups[attr++] = &rc_dev_ro_protocol_attr_grp;
  	else if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
  		dev->sysfs_groups[attr++] = &rc_dev_rw_protocol_attr_grp;
  	if (dev->s_filter)
  		dev->sysfs_groups[attr++] = &rc_dev_filter_attr_grp;
  	if (dev->s_wakeup_filter)
  		dev->sysfs_groups[attr++] = &rc_dev_wakeup_filter_attr_grp;
  	dev->sysfs_groups[attr++] = NULL;
  
  	if (dev->driver_type == RC_DRIVER_IR_RAW) {
  		rc = ir_raw_event_prepare(dev);
  		if (rc < 0)
  			goto out_minor;
  	}
  
  	if (dev->driver_type != RC_DRIVER_IR_RAW_TX) {
  		rc = rc_prepare_rx_device(dev);
  		if (rc)
  			goto out_raw;
  	}
  
  	rc = device_add(&dev->dev);
  	if (rc)
  		goto out_rx_free;
  
  	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
  	dev_info(&dev->dev, "%s as %s\n",
  		 dev->device_name ?: "Unspecified device", path ?: "N/A");
  	kfree(path);
  
  	dev->registered = true;
  
  	if (dev->driver_type != RC_DRIVER_IR_RAW_TX) {
  		rc = rc_setup_rx_device(dev);
  		if (rc)
  			goto out_dev;
  	}
  
  	/* Ensure that the lirc kfifo is setup before we start the thread */
  	if (dev->allowed_protocols != RC_PROTO_BIT_CEC) {
  		rc = ir_lirc_register(dev);
  		if (rc < 0)
  			goto out_rx;
  	}
  
  	if (dev->driver_type == RC_DRIVER_IR_RAW) {
  		rc = ir_raw_event_register(dev);
  		if (rc < 0)
  			goto out_lirc;
  	}
  
  	dev_dbg(&dev->dev, "Registered rc%u (driver: %s)\n", dev->minor,
  		dev->driver_name ? dev->driver_name : "unknown");
  
  	return 0;
  
  out_lirc:
  	if (dev->allowed_protocols != RC_PROTO_BIT_CEC)
  		ir_lirc_unregister(dev);
  out_rx:
  	rc_free_rx_device(dev);
  out_dev:
  	device_del(&dev->dev);
  out_rx_free:
  	ir_free_table(&dev->rc_map);
  out_raw:
  	ir_raw_event_free(dev);
  out_minor:
  	ida_simple_remove(&rc_ida, minor);
  	return rc;
  }
  EXPORT_SYMBOL_GPL(rc_register_device);
  
  static void devm_rc_release(struct device *dev, void *res)
  {
  	rc_unregister_device(*(struct rc_dev **)res);
  }
  
  int devm_rc_register_device(struct device *parent, struct rc_dev *dev)
  {
  	struct rc_dev **dr;
  	int ret;
  
  	dr = devres_alloc(devm_rc_release, sizeof(*dr), GFP_KERNEL);
  	if (!dr)
  		return -ENOMEM;
  
  	ret = rc_register_device(dev);
  	if (ret) {
  		devres_free(dr);
  		return ret;
  	}
  
  	*dr = dev;
  	devres_add(parent, dr);
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(devm_rc_register_device);
  
  void rc_unregister_device(struct rc_dev *dev)
  {
  	if (!dev)
  		return;
  
  	if (dev->driver_type == RC_DRIVER_IR_RAW)
  		ir_raw_event_unregister(dev);
  
  	del_timer_sync(&dev->timer_keyup);
  	del_timer_sync(&dev->timer_repeat);
  
  	rc_free_rx_device(dev);
  
  	mutex_lock(&dev->lock);
  	if (dev->users && dev->close)
  		dev->close(dev);
  	dev->registered = false;
  	mutex_unlock(&dev->lock);
  
  	/*
  	 * lirc device should be freed with dev->registered = false, so
  	 * that userspace polling will get notified.
  	 */
  	if (dev->allowed_protocols != RC_PROTO_BIT_CEC)
  		ir_lirc_unregister(dev);
  
  	device_del(&dev->dev);
  
  	ida_simple_remove(&rc_ida, dev->minor);
  
  	if (!dev->managed_alloc)
  		rc_free_device(dev);
  }
  
  EXPORT_SYMBOL_GPL(rc_unregister_device);
  
  /*
   * Init/exit code for the module. Basically, creates/removes /sys/class/rc
   */
  
  static int __init rc_core_init(void)
  {
  	int rc = class_register(&rc_class);
  	if (rc) {
  		pr_err("rc_core: unable to register rc class\n");
  		return rc;
  	}
  
  	rc = lirc_dev_init();
  	if (rc) {
  		pr_err("rc_core: unable to init lirc\n");
  		class_unregister(&rc_class);
  		return 0;
  	}
  
  	led_trigger_register_simple("rc-feedback", &led_feedback);
  	rc_map_register(&empty_map);
  
  	return 0;
  }
  
  static void __exit rc_core_exit(void)
  {
  	lirc_dev_exit();
  	class_unregister(&rc_class);
  	led_trigger_unregister_simple(led_feedback);
  	rc_map_unregister(&empty_map);
  }
  
  subsys_initcall(rc_core_init);
  module_exit(rc_core_exit);
  
  MODULE_AUTHOR("Mauro Carvalho Chehab");
  MODULE_LICENSE("GPL v2");
  