drivers/media/IR/ir-keytable.c - kernel/skids - Git at Google

 /* ir-keytable.c - handle IR scancode->keycode tables
  *
  * Copyright (C) 2009 by Mauro Carvalho Chehab <mchehab@redhat.com>
  *
  * This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation version 2 of the License.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  */


 #include <linux/input.h>
 #include <linux/slab.h>
 #include "ir-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

 /* FIXME: IR_KEYPRESS_TIMEOUT should be protocol specific */
 #define IR_KEYPRESS_TIMEOUT 250

 /**
  * ir_resize_table() - resizes a scancode table if necessary
  * @rc_tab:	the ir_scancode_table to resize
  * @return:	zero on success or a negative error code
  *
  * This routine will shrink the ir_scancode_table if it has lots of
  * unused entries and grow it if it is full.
  */
 static int ir_resize_table(struct ir_scancode_table *rc_tab)
 {
 	unsigned int oldalloc = rc_tab->alloc;
 	unsigned int newalloc = oldalloc;
 	struct ir_scancode *oldscan = rc_tab->scan;
 	struct ir_scancode *newscan;

 	if (rc_tab->size == rc_tab->len) {
 		/* All entries in use -> grow keytable */
 		if (rc_tab->alloc >= IR_TAB_MAX_SIZE)
 			return -ENOMEM;

 		newalloc *= 2;
 		IR_dprintk(1, "Growing table to %u bytes\n", newalloc);
 	}

 	if ((rc_tab->len * 3 < rc_tab->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
 		/* Less than 1/3 of entries in use -> shrink keytable */
 		newalloc /= 2;
 		IR_dprintk(1, "Shrinking table to %u bytes\n", newalloc);
 	}

 	if (newalloc == oldalloc)
 		return 0;

 	newscan = kmalloc(newalloc, GFP_ATOMIC);
 	if (!newscan) {
 		IR_dprintk(1, "Failed to kmalloc %u bytes\n", newalloc);
 		return -ENOMEM;
 	}

 	memcpy(newscan, rc_tab->scan, rc_tab->len * sizeof(struct ir_scancode));
 	rc_tab->scan = newscan;
 	rc_tab->alloc = newalloc;
 	rc_tab->size = rc_tab->alloc / sizeof(struct ir_scancode);
 	kfree(oldscan);
 	return 0;
 }

 /**
  * ir_do_setkeycode() - internal function to set a keycode in the
  *			scancode->keycode table
  * @dev:	the struct input_dev device descriptor
  * @rc_tab:	the struct ir_scancode_table to set the keycode in
  * @scancode:	the scancode for the ir command
  * @keycode:	the keycode for the ir command
  * @resize:	whether the keytable may be shrunk
  * @return:	-EINVAL if the keycode could not be inserted, otherwise zero.
  *
  * This routine is used internally to manipulate the scancode->keycode table.
  * The caller has to hold @rc_tab->lock.
  */
 static int ir_do_setkeycode(struct input_dev *dev,
 			    struct ir_scancode_table *rc_tab,
 			    unsigned scancode, unsigned keycode,
 			    bool resize)
 {
 	unsigned int i;
 	int old_keycode = KEY_RESERVED;
 	struct ir_input_dev *ir_dev = input_get_drvdata(dev);

 	/*
 	 * 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,
 	 */
 	if (ir_dev->props && ir_dev->props->scanmask) {
 		scancode &= ir_dev->props->scanmask;
 	}

 	/* First check if we already have a mapping for this ir command */
 	for (i = 0; i < rc_tab->len; i++) {
 		/* Keytable is sorted from lowest to highest scancode */
 		if (rc_tab->scan[i].scancode > scancode)
 			break;
 		else if (rc_tab->scan[i].scancode < scancode)
 			continue;

 		old_keycode = rc_tab->scan[i].keycode;
 		rc_tab->scan[i].keycode = keycode;

 		/* Did the user wish to remove the mapping? */
 		if (keycode == KEY_RESERVED || keycode == KEY_UNKNOWN) {
 			IR_dprintk(1, "#%d: Deleting scan 0x%04x\n",
 				   i, scancode);
 			rc_tab->len--;
 			memmove(&rc_tab->scan[i], &rc_tab->scan[i + 1],
 				(rc_tab->len - i) * sizeof(struct ir_scancode));
 		}

 		/* Possibly shrink the keytable, failure is not a problem */
 		ir_resize_table(rc_tab);
 		break;
 	}

 	if (old_keycode == KEY_RESERVED && keycode != KEY_RESERVED) {
 		/* No previous mapping found, we might need to grow the table */
 		if (resize && ir_resize_table(rc_tab))
 			return -ENOMEM;

 		IR_dprintk(1, "#%d: New scan 0x%04x with key 0x%04x\n",
 			   i, scancode, keycode);

 		/* i is the proper index to insert our new keycode */
 		memmove(&rc_tab->scan[i + 1], &rc_tab->scan[i],
 			(rc_tab->len - i) * sizeof(struct ir_scancode));
 		rc_tab->scan[i].scancode = scancode;
 		rc_tab->scan[i].keycode = keycode;
 		rc_tab->len++;
 		set_bit(keycode, dev->keybit);
 	} else {
 		IR_dprintk(1, "#%d: Replacing scan 0x%04x with key 0x%04x\n",
 			   i, scancode, keycode);
 		/* A previous mapping was updated... */
 		clear_bit(old_keycode, dev->keybit);
 		/* ...but another scancode might use the same keycode */
 		for (i = 0; i < rc_tab->len; i++) {
 			if (rc_tab->scan[i].keycode == old_keycode) {
 				set_bit(old_keycode, dev->keybit);
 				break;
 			}
 		}
 	}

 	return 0;
 }

 /**
  * ir_setkeycode() - set a keycode in the scancode->keycode table
  * @dev:	the struct input_dev device descriptor
  * @scancode:	the desired scancode
  * @keycode:	result
  * @return:	-EINVAL if the keycode could not be inserted, otherwise zero.
  *
  * This routine is used to handle evdev EVIOCSKEY ioctl.
  */
 static int ir_setkeycode(struct input_dev *dev,
 			 unsigned int scancode, unsigned int keycode)
 {
 	int rc;
 	unsigned long flags;
 	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
 	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

 	spin_lock_irqsave(&rc_tab->lock, flags);
 	rc = ir_do_setkeycode(dev, rc_tab, scancode, keycode, true);
 	spin_unlock_irqrestore(&rc_tab->lock, flags);
 	return rc;
 }

 /**
  * ir_setkeytable() - sets several entries in the scancode->keycode table
  * @dev:	the struct input_dev device descriptor
  * @to:		the struct ir_scancode_table to copy entries to
  * @from:	the struct ir_scancode_table to copy entries from
  * @return:	-EINVAL if all keycodes could not be inserted, otherwise zero.
  *
  * This routine is used to handle table initialization.
  */
 static int ir_setkeytable(struct input_dev *dev,
 			  struct ir_scancode_table *to,
 			  const struct ir_scancode_table *from)
 {
 	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
 	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
 	unsigned long flags;
 	unsigned int i;
 	int rc = 0;

 	spin_lock_irqsave(&rc_tab->lock, flags);
 	for (i = 0; i < from->size; i++) {
 		rc = ir_do_setkeycode(dev, to, from->scan[i].scancode,
 				      from->scan[i].keycode, false);
 		if (rc)
 			break;
 	}
 	spin_unlock_irqrestore(&rc_tab->lock, flags);
 	return rc;
 }

 /**
  * ir_getkeycode() - get a keycode from the scancode->keycode table
  * @dev:	the struct input_dev device descriptor
  * @scancode:	the desired scancode
  * @keycode:	used to return the keycode, if found, or KEY_RESERVED
  * @return:	always returns zero.
  *
  * This routine is used to handle evdev EVIOCGKEY ioctl.
  */
 static int ir_getkeycode(struct input_dev *dev,
 			 unsigned int scancode, unsigned int *keycode)
 {
 	int start, end, mid;
 	unsigned long flags;
 	int key = KEY_RESERVED;
 	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
 	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

 	spin_lock_irqsave(&rc_tab->lock, flags);
 	start = 0;
 	end = rc_tab->len - 1;
 	while (start <= end) {
 		mid = (start + end) / 2;
 		if (rc_tab->scan[mid].scancode < scancode)
 			start = mid + 1;
 		else if (rc_tab->scan[mid].scancode > scancode)
 			end = mid - 1;
 		else {
 			key = rc_tab->scan[mid].keycode;
 			break;
 		}
 	}
 	spin_unlock_irqrestore(&rc_tab->lock, flags);

 	if (key == KEY_RESERVED)
 		IR_dprintk(1, "unknown key for scancode 0x%04x\n",
 			   scancode);

 	*keycode = key;
 	return 0;
 }

 /**
  * ir_g_keycode_from_table() - gets the keycode that corresponds to a scancode
  * @input_dev:	the struct input_dev descriptor of the device
  * @scancode:	the scancode that we're seeking
  *
  * This routine is used by the input routines when a key is pressed at the
  * IR. The scancode is received and needs to be converted into a keycode.
  * If the key is not found, it returns KEY_RESERVED. Otherwise, returns the
  * corresponding keycode from the table.
  */
 u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
 {
 	int keycode;

 	ir_getkeycode(dev, scancode, &keycode);
 	if (keycode != KEY_RESERVED)
 		IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
 			   dev->name, scancode, keycode);
 	return keycode;
 }
 EXPORT_SYMBOL_GPL(ir_g_keycode_from_table);

 /**
  * ir_keyup() - generates input event to cleanup a key press
  * @ir:         the struct ir_input_dev descriptor of the device
  *
  * This routine is used to signal that a key has been released on the
  * remote control. It reports a keyup input event via input_report_key().
  */
 static void ir_keyup(struct ir_input_dev *ir)
 {
 	if (!ir->keypressed)
 		return;

 	IR_dprintk(1, "keyup key 0x%04x\n", ir->last_keycode);
 	input_report_key(ir->input_dev, ir->last_keycode, 0);
 	input_sync(ir->input_dev);
 	ir->keypressed = false;
 }

 /**
  * ir_timer_keyup() - generates a keyup event after a timeout
  * @cookie:     a pointer to struct ir_input_dev passed to setup_timer()
  *
  * 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(unsigned long cookie)
 {
 	struct ir_input_dev *ir = (struct ir_input_dev *)cookie;
 	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(&ir->keylock, flags);
 	if (time_is_before_eq_jiffies(ir->keyup_jiffies))
 		ir_keyup(ir);
 	spin_unlock_irqrestore(&ir->keylock, flags);
 }

 /**
  * ir_repeat() - notifies the IR core that a key is still pressed
  * @dev:        the struct input_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 ir_repeat(struct input_dev *dev)
 {
 	unsigned long flags;
 	struct ir_input_dev *ir = input_get_drvdata(dev);

 	spin_lock_irqsave(&ir->keylock, flags);

 	if (!ir->keypressed)
 		goto out;

 	ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
 	mod_timer(&ir->timer_keyup, ir->keyup_jiffies);

 out:
 	spin_unlock_irqrestore(&ir->keylock, flags);
 }
 EXPORT_SYMBOL_GPL(ir_repeat);

 /**
  * ir_keydown() - generates input event for a key press
  * @dev:        the struct input_dev descriptor of the device
  * @scancode:   the scancode that we're seeking
  * @toggle:     the toggle value (protocol dependent, if the protocol doesn't
  *              support toggle values, this should be set to zero)
  *
  * This routine is used by the input routines when a key is pressed at the
  * IR. It gets the keycode for a scancode and reports an input event via
  * input_report_key().
  */
 void ir_keydown(struct input_dev *dev, int scancode, u8 toggle)
 {
 	unsigned long flags;
 	struct ir_input_dev *ir = input_get_drvdata(dev);

 	u32 keycode = ir_g_keycode_from_table(dev, scancode);

 	spin_lock_irqsave(&ir->keylock, flags);

 	/* Repeat event? */
 	if (ir->keypressed &&
 	    ir->last_scancode == scancode &&
 	    ir->last_toggle == toggle)
 		goto set_timer;

 	/* Release old keypress */
 	ir_keyup(ir);

 	ir->last_scancode = scancode;
 	ir->last_toggle = toggle;
 	ir->last_keycode = keycode;

 	if (keycode == KEY_RESERVED)
 		goto out;

 	/* Register a keypress */
 	ir->keypressed = true;
 	IR_dprintk(1, "%s: key down event, key 0x%04x, scancode 0x%04x\n",
 		   dev->name, keycode, scancode);
 	input_report_key(dev, ir->last_keycode, 1);
 	input_sync(dev);

 set_timer:
 	ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
 	mod_timer(&ir->timer_keyup, ir->keyup_jiffies);
 out:
 	spin_unlock_irqrestore(&ir->keylock, flags);
 }
 EXPORT_SYMBOL_GPL(ir_keydown);

 static int ir_open(struct input_dev *input_dev)
 {
 	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);

 	return ir_dev->props->open(ir_dev->props->priv);
 }

 static void ir_close(struct input_dev *input_dev)
 {
 	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);

 	ir_dev->props->close(ir_dev->props->priv);
 }

 /**
  * __ir_input_register() - sets the IR keycode table and add the handlers
  *			    for keymap table get/set
  * @input_dev:	the struct input_dev descriptor of the device
  * @rc_tab:	the struct ir_scancode_table table of scancode/keymap
  *
  * This routine is used to initialize the input infrastructure
  * to work with an IR.
  * It will register the input/evdev interface for the device and
  * register the syfs code for IR class
  */
 int __ir_input_register(struct input_dev *input_dev,
 		      const struct ir_scancode_table *rc_tab,
 		      const struct ir_dev_props *props,
 		      const char *driver_name)
 {
 	struct ir_input_dev *ir_dev;
 	int rc;

 	if (rc_tab->scan == NULL || !rc_tab->size)
 		return -EINVAL;

 	ir_dev = kzalloc(sizeof(*ir_dev), GFP_KERNEL);
 	if (!ir_dev)
 		return -ENOMEM;

 	ir_dev->driver_name = kasprintf(GFP_KERNEL, "%s", driver_name);
 	if (!ir_dev->driver_name) {
 		rc = -ENOMEM;
 		goto out_dev;
 	}

 	input_dev->getkeycode = ir_getkeycode;
 	input_dev->setkeycode = ir_setkeycode;
 	input_set_drvdata(input_dev, ir_dev);
 	ir_dev->input_dev = input_dev;

 	spin_lock_init(&ir_dev->rc_tab.lock);
 	spin_lock_init(&ir_dev->keylock);
 	setup_timer(&ir_dev->timer_keyup, ir_timer_keyup, (unsigned long)ir_dev);

 	ir_dev->rc_tab.name = rc_tab->name;
 	ir_dev->rc_tab.ir_type = rc_tab->ir_type;
 	ir_dev->rc_tab.alloc = roundup_pow_of_two(rc_tab->size *
 						  sizeof(struct ir_scancode));
 	ir_dev->rc_tab.scan = kmalloc(ir_dev->rc_tab.alloc, GFP_KERNEL);
 	ir_dev->rc_tab.size = ir_dev->rc_tab.alloc / sizeof(struct ir_scancode);
 	if (props) {
 		ir_dev->props = props;
 		if (props->open)
 			input_dev->open = ir_open;
 		if (props->close)
 			input_dev->close = ir_close;
 	}

 	if (!ir_dev->rc_tab.scan) {
 		rc = -ENOMEM;
 		goto out_name;
 	}

 	IR_dprintk(1, "Allocated space for %u keycode entries (%u bytes)\n",
 		   ir_dev->rc_tab.size, ir_dev->rc_tab.alloc);

 	set_bit(EV_KEY, input_dev->evbit);
 	set_bit(EV_REP, input_dev->evbit);

 	if (ir_setkeytable(input_dev, &ir_dev->rc_tab, rc_tab)) {
 		rc = -ENOMEM;
 		goto out_table;
 	}

 	rc = ir_register_class(input_dev);
 	if (rc < 0)
 		goto out_table;

 	if (ir_dev->props)
 		if (ir_dev->props->driver_type == RC_DRIVER_IR_RAW) {
 			rc = ir_raw_event_register(input_dev);
 			if (rc < 0)
 				goto out_event;
 		}

 	IR_dprintk(1, "Registered input device on %s for %s remote.\n",
 		   driver_name, rc_tab->name);

 	return 0;

 out_event:
 	ir_unregister_class(input_dev);
 out_table:
 	kfree(ir_dev->rc_tab.scan);
 out_name:
 	kfree(ir_dev->driver_name);
 out_dev:
 	kfree(ir_dev);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(__ir_input_register);

 /**
  * ir_input_unregister() - unregisters IR and frees resources
  * @input_dev:	the struct input_dev descriptor of the device

  * This routine is used to free memory and de-register interfaces.
  */
 void ir_input_unregister(struct input_dev *input_dev)
 {
 	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
 	struct ir_scancode_table *rc_tab;

 	if (!ir_dev)
 		return;

 	IR_dprintk(1, "Freed keycode table\n");

 	del_timer_sync(&ir_dev->timer_keyup);
 	if (ir_dev->props)
 		if (ir_dev->props->driver_type == RC_DRIVER_IR_RAW)
 			ir_raw_event_unregister(input_dev);

 	rc_tab = &ir_dev->rc_tab;
 	rc_tab->size = 0;
 	kfree(rc_tab->scan);
 	rc_tab->scan = NULL;

 	ir_unregister_class(input_dev);

 	kfree(ir_dev->driver_name);
 	kfree(ir_dev);
 }
 EXPORT_SYMBOL_GPL(ir_input_unregister);

 int ir_core_debug;    /* ir_debug level (0,1,2) */
 EXPORT_SYMBOL_GPL(ir_core_debug);
 module_param_named(debug, ir_core_debug, int, 0644);

 MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
 MODULE_LICENSE("GPL");
	/* ir-keytable.c - handle IR scancode->keycode tables
	*
	* Copyright (C) 2009 by Mauro Carvalho Chehab <mchehab@redhat.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation version 2 of the License.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/


	#include <linux/input.h>
	#include <linux/slab.h>
	#include "ir-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

	/* FIXME: IR_KEYPRESS_TIMEOUT should be protocol specific */
	#define IR_KEYPRESS_TIMEOUT 250

	/**
	* ir_resize_table() - resizes a scancode table if necessary
	* @rc_tab: the ir_scancode_table to resize
	* @return: zero on success or a negative error code
	*
	* This routine will shrink the ir_scancode_table if it has lots of
	* unused entries and grow it if it is full.
	*/
	static int ir_resize_table(struct ir_scancode_table *rc_tab)
	{
	unsigned int oldalloc = rc_tab->alloc;
	unsigned int newalloc = oldalloc;
	struct ir_scancode *oldscan = rc_tab->scan;
	struct ir_scancode *newscan;

	if (rc_tab->size == rc_tab->len) {
	/* All entries in use -> grow keytable */
	if (rc_tab->alloc >= IR_TAB_MAX_SIZE)
	return -ENOMEM;

	newalloc *= 2;
	IR_dprintk(1, "Growing table to %u bytes\n", newalloc);
	}

	if ((rc_tab->len * 3 < rc_tab->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
	/* Less than 1/3 of entries in use -> shrink keytable */
	newalloc /= 2;
	IR_dprintk(1, "Shrinking table to %u bytes\n", newalloc);
	}

	if (newalloc == oldalloc)
	return 0;

	newscan = kmalloc(newalloc, GFP_ATOMIC);
	if (!newscan) {
	IR_dprintk(1, "Failed to kmalloc %u bytes\n", newalloc);
	return -ENOMEM;
	}

	memcpy(newscan, rc_tab->scan, rc_tab->len * sizeof(struct ir_scancode));
	rc_tab->scan = newscan;
	rc_tab->alloc = newalloc;
	rc_tab->size = rc_tab->alloc / sizeof(struct ir_scancode);
	kfree(oldscan);
	return 0;
	}

	/**
	* ir_do_setkeycode() - internal function to set a keycode in the
	* scancode->keycode table
	* @dev: the struct input_dev device descriptor
	* @rc_tab: the struct ir_scancode_table to set the keycode in
	* @scancode: the scancode for the ir command
	* @keycode: the keycode for the ir command
	* @resize: whether the keytable may be shrunk
	* @return: -EINVAL if the keycode could not be inserted, otherwise zero.
	*
	* This routine is used internally to manipulate the scancode->keycode table.
	* The caller has to hold @rc_tab->lock.
	*/
	static int ir_do_setkeycode(struct input_dev *dev,
	struct ir_scancode_table *rc_tab,
	unsigned scancode, unsigned keycode,
	bool resize)
	{
	unsigned int i;
	int old_keycode = KEY_RESERVED;
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);

	/*
	* 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,
	*/
	if (ir_dev->props && ir_dev->props->scanmask) {
	scancode &= ir_dev->props->scanmask;
	}

	/* First check if we already have a mapping for this ir command */
	for (i = 0; i < rc_tab->len; i++) {
	/* Keytable is sorted from lowest to highest scancode */
	if (rc_tab->scan[i].scancode > scancode)
	break;
	else if (rc_tab->scan[i].scancode < scancode)
	continue;

	old_keycode = rc_tab->scan[i].keycode;
	rc_tab->scan[i].keycode = keycode;

	/* Did the user wish to remove the mapping? */
	if (keycode == KEY_RESERVED \|\| keycode == KEY_UNKNOWN) {
	IR_dprintk(1, "#%d: Deleting scan 0x%04x\n",
	i, scancode);
	rc_tab->len--;
	memmove(&rc_tab->scan[i], &rc_tab->scan[i + 1],
	(rc_tab->len - i) * sizeof(struct ir_scancode));
	}

	/* Possibly shrink the keytable, failure is not a problem */
	ir_resize_table(rc_tab);
	break;
	}

	if (old_keycode == KEY_RESERVED && keycode != KEY_RESERVED) {
	/* No previous mapping found, we might need to grow the table */
	if (resize && ir_resize_table(rc_tab))
	return -ENOMEM;

	IR_dprintk(1, "#%d: New scan 0x%04x with key 0x%04x\n",
	i, scancode, keycode);

	/* i is the proper index to insert our new keycode */
	memmove(&rc_tab->scan[i + 1], &rc_tab->scan[i],
	(rc_tab->len - i) * sizeof(struct ir_scancode));
	rc_tab->scan[i].scancode = scancode;
	rc_tab->scan[i].keycode = keycode;
	rc_tab->len++;
	set_bit(keycode, dev->keybit);
	} else {
	IR_dprintk(1, "#%d: Replacing scan 0x%04x with key 0x%04x\n",
	i, scancode, keycode);
	/* A previous mapping was updated... */
	clear_bit(old_keycode, dev->keybit);
	/* ...but another scancode might use the same keycode */
	for (i = 0; i < rc_tab->len; i++) {
	if (rc_tab->scan[i].keycode == old_keycode) {
	set_bit(old_keycode, dev->keybit);
	break;
	}
	}
	}

	return 0;
	}

	/**
	* ir_setkeycode() - set a keycode in the scancode->keycode table
	* @dev: the struct input_dev device descriptor
	* @scancode: the desired scancode
	* @keycode: result
	* @return: -EINVAL if the keycode could not be inserted, otherwise zero.
	*
	* This routine is used to handle evdev EVIOCSKEY ioctl.
	*/
	static int ir_setkeycode(struct input_dev *dev,
	unsigned int scancode, unsigned int keycode)
	{
	int rc;
	unsigned long flags;
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

	spin_lock_irqsave(&rc_tab->lock, flags);
	rc = ir_do_setkeycode(dev, rc_tab, scancode, keycode, true);
	spin_unlock_irqrestore(&rc_tab->lock, flags);
	return rc;
	}

	/**
	* ir_setkeytable() - sets several entries in the scancode->keycode table
	* @dev: the struct input_dev device descriptor
	* @to: the struct ir_scancode_table to copy entries to
	* @from: the struct ir_scancode_table to copy entries from
	* @return: -EINVAL if all keycodes could not be inserted, otherwise zero.
	*
	* This routine is used to handle table initialization.
	*/
	static int ir_setkeytable(struct input_dev *dev,
	struct ir_scancode_table *to,
	const struct ir_scancode_table *from)
	{
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
	unsigned long flags;
	unsigned int i;
	int rc = 0;

	spin_lock_irqsave(&rc_tab->lock, flags);
	for (i = 0; i < from->size; i++) {
	rc = ir_do_setkeycode(dev, to, from->scan[i].scancode,
	from->scan[i].keycode, false);
	if (rc)
	break;
	}
	spin_unlock_irqrestore(&rc_tab->lock, flags);
	return rc;
	}

	/**
	* ir_getkeycode() - get a keycode from the scancode->keycode table
	* @dev: the struct input_dev device descriptor
	* @scancode: the desired scancode
	* @keycode: used to return the keycode, if found, or KEY_RESERVED
	* @return: always returns zero.
	*
	* This routine is used to handle evdev EVIOCGKEY ioctl.
	*/
	static int ir_getkeycode(struct input_dev *dev,
	unsigned int scancode, unsigned int *keycode)
	{
	int start, end, mid;
	unsigned long flags;
	int key = KEY_RESERVED;
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

	spin_lock_irqsave(&rc_tab->lock, flags);
	start = 0;
	end = rc_tab->len - 1;
	while (start <= end) {
	mid = (start + end) / 2;
	if (rc_tab->scan[mid].scancode < scancode)
	start = mid + 1;
	else if (rc_tab->scan[mid].scancode > scancode)
	end = mid - 1;
	else {
	key = rc_tab->scan[mid].keycode;
	break;
	}
	}
	spin_unlock_irqrestore(&rc_tab->lock, flags);

	if (key == KEY_RESERVED)
	IR_dprintk(1, "unknown key for scancode 0x%04x\n",
	scancode);

	*keycode = key;
	return 0;
	}

	/**
	* ir_g_keycode_from_table() - gets the keycode that corresponds to a scancode
	* @input_dev: the struct input_dev descriptor of the device
	* @scancode: the scancode that we're seeking
	*
	* This routine is used by the input routines when a key is pressed at the
	* IR. The scancode is received and needs to be converted into a keycode.
	* If the key is not found, it returns KEY_RESERVED. Otherwise, returns the
	* corresponding keycode from the table.
	*/
	u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
	{
	int keycode;

	ir_getkeycode(dev, scancode, &keycode);
	if (keycode != KEY_RESERVED)
	IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
	dev->name, scancode, keycode);
	return keycode;
	}
	EXPORT_SYMBOL_GPL(ir_g_keycode_from_table);

	/**
	* ir_keyup() - generates input event to cleanup a key press
	* @ir: the struct ir_input_dev descriptor of the device
	*
	* This routine is used to signal that a key has been released on the
	* remote control. It reports a keyup input event via input_report_key().
	*/
	static void ir_keyup(struct ir_input_dev *ir)
	{
	if (!ir->keypressed)
	return;

	IR_dprintk(1, "keyup key 0x%04x\n", ir->last_keycode);
	input_report_key(ir->input_dev, ir->last_keycode, 0);
	input_sync(ir->input_dev);
	ir->keypressed = false;
	}

	/**
	* ir_timer_keyup() - generates a keyup event after a timeout
	* @cookie: a pointer to struct ir_input_dev passed to setup_timer()
	*
	* 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(unsigned long cookie)
	{
	struct ir_input_dev ir = (struct ir_input_dev )cookie;
	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(&ir->keylock, flags);
	if (time_is_before_eq_jiffies(ir->keyup_jiffies))
	ir_keyup(ir);
	spin_unlock_irqrestore(&ir->keylock, flags);
	}

	/**
	* ir_repeat() - notifies the IR core that a key is still pressed
	* @dev: the struct input_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 ir_repeat(struct input_dev *dev)
	{
	unsigned long flags;
	struct ir_input_dev *ir = input_get_drvdata(dev);

	spin_lock_irqsave(&ir->keylock, flags);

	if (!ir->keypressed)
	goto out;

	ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
	mod_timer(&ir->timer_keyup, ir->keyup_jiffies);

	out:
	spin_unlock_irqrestore(&ir->keylock, flags);
	}
	EXPORT_SYMBOL_GPL(ir_repeat);

	/**
	* ir_keydown() - generates input event for a key press
	* @dev: the struct input_dev descriptor of the device
	* @scancode: the scancode that we're seeking
	* @toggle: the toggle value (protocol dependent, if the protocol doesn't
	* support toggle values, this should be set to zero)
	*
	* This routine is used by the input routines when a key is pressed at the
	* IR. It gets the keycode for a scancode and reports an input event via
	* input_report_key().
	*/
	void ir_keydown(struct input_dev *dev, int scancode, u8 toggle)
	{
	unsigned long flags;
	struct ir_input_dev *ir = input_get_drvdata(dev);

	u32 keycode = ir_g_keycode_from_table(dev, scancode);

	spin_lock_irqsave(&ir->keylock, flags);

	/* Repeat event? */
	if (ir->keypressed &&
	ir->last_scancode == scancode &&
	ir->last_toggle == toggle)
	goto set_timer;

	/* Release old keypress */
	ir_keyup(ir);

	ir->last_scancode = scancode;
	ir->last_toggle = toggle;
	ir->last_keycode = keycode;

	if (keycode == KEY_RESERVED)
	goto out;

	/* Register a keypress */
	ir->keypressed = true;
	IR_dprintk(1, "%s: key down event, key 0x%04x, scancode 0x%04x\n",
	dev->name, keycode, scancode);
	input_report_key(dev, ir->last_keycode, 1);
	input_sync(dev);

	set_timer:
	ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
	mod_timer(&ir->timer_keyup, ir->keyup_jiffies);
	out:
	spin_unlock_irqrestore(&ir->keylock, flags);
	}
	EXPORT_SYMBOL_GPL(ir_keydown);

	static int ir_open(struct input_dev *input_dev)
	{
	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);

	return ir_dev->props->open(ir_dev->props->priv);
	}

	static void ir_close(struct input_dev *input_dev)
	{
	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);

	ir_dev->props->close(ir_dev->props->priv);
	}

	/**
	* __ir_input_register() - sets the IR keycode table and add the handlers
	* for keymap table get/set
	* @input_dev: the struct input_dev descriptor of the device
	* @rc_tab: the struct ir_scancode_table table of scancode/keymap
	*
	* This routine is used to initialize the input infrastructure
	* to work with an IR.
	* It will register the input/evdev interface for the device and
	* register the syfs code for IR class
	*/
	int __ir_input_register(struct input_dev *input_dev,
	const struct ir_scancode_table *rc_tab,
	const struct ir_dev_props *props,
	const char *driver_name)
	{
	struct ir_input_dev *ir_dev;
	int rc;

	if (rc_tab->scan == NULL \|\| !rc_tab->size)
	return -EINVAL;

	ir_dev = kzalloc(sizeof(*ir_dev), GFP_KERNEL);
	if (!ir_dev)
	return -ENOMEM;

	ir_dev->driver_name = kasprintf(GFP_KERNEL, "%s", driver_name);
	if (!ir_dev->driver_name) {
	rc = -ENOMEM;
	goto out_dev;
	}

	input_dev->getkeycode = ir_getkeycode;
	input_dev->setkeycode = ir_setkeycode;
	input_set_drvdata(input_dev, ir_dev);
	ir_dev->input_dev = input_dev;

	spin_lock_init(&ir_dev->rc_tab.lock);
	spin_lock_init(&ir_dev->keylock);
	setup_timer(&ir_dev->timer_keyup, ir_timer_keyup, (unsigned long)ir_dev);

	ir_dev->rc_tab.name = rc_tab->name;
	ir_dev->rc_tab.ir_type = rc_tab->ir_type;
	ir_dev->rc_tab.alloc = roundup_pow_of_two(rc_tab->size *
	sizeof(struct ir_scancode));
	ir_dev->rc_tab.scan = kmalloc(ir_dev->rc_tab.alloc, GFP_KERNEL);
	ir_dev->rc_tab.size = ir_dev->rc_tab.alloc / sizeof(struct ir_scancode);
	if (props) {
	ir_dev->props = props;
	if (props->open)
	input_dev->open = ir_open;
	if (props->close)
	input_dev->close = ir_close;
	}

	if (!ir_dev->rc_tab.scan) {
	rc = -ENOMEM;
	goto out_name;
	}

	IR_dprintk(1, "Allocated space for %u keycode entries (%u bytes)\n",
	ir_dev->rc_tab.size, ir_dev->rc_tab.alloc);

	set_bit(EV_KEY, input_dev->evbit);
	set_bit(EV_REP, input_dev->evbit);

	if (ir_setkeytable(input_dev, &ir_dev->rc_tab, rc_tab)) {
	rc = -ENOMEM;
	goto out_table;
	}

	rc = ir_register_class(input_dev);
	if (rc < 0)
	goto out_table;

	if (ir_dev->props)
	if (ir_dev->props->driver_type == RC_DRIVER_IR_RAW) {
	rc = ir_raw_event_register(input_dev);
	if (rc < 0)
	goto out_event;
	}

	IR_dprintk(1, "Registered input device on %s for %s remote.\n",
	driver_name, rc_tab->name);

	return 0;

	out_event:
	ir_unregister_class(input_dev);
	out_table:
	kfree(ir_dev->rc_tab.scan);
	out_name:
	kfree(ir_dev->driver_name);
	out_dev:
	kfree(ir_dev);
	return rc;
	}
	EXPORT_SYMBOL_GPL(__ir_input_register);

	/**
	* ir_input_unregister() - unregisters IR and frees resources
	* @input_dev: the struct input_dev descriptor of the device

	* This routine is used to free memory and de-register interfaces.
	*/
	void ir_input_unregister(struct input_dev *input_dev)
	{
	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
	struct ir_scancode_table *rc_tab;

	if (!ir_dev)
	return;

	IR_dprintk(1, "Freed keycode table\n");

	del_timer_sync(&ir_dev->timer_keyup);
	if (ir_dev->props)
	if (ir_dev->props->driver_type == RC_DRIVER_IR_RAW)
	ir_raw_event_unregister(input_dev);

	rc_tab = &ir_dev->rc_tab;
	rc_tab->size = 0;
	kfree(rc_tab->scan);
	rc_tab->scan = NULL;

	ir_unregister_class(input_dev);

	kfree(ir_dev->driver_name);
	kfree(ir_dev);
	}
	EXPORT_SYMBOL_GPL(ir_input_unregister);

	int ir_core_debug; /* ir_debug level (0,1,2) */
	EXPORT_SYMBOL_GPL(ir_core_debug);
	module_param_named(debug, ir_core_debug, int, 0644);

	MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
	MODULE_LICENSE("GPL");