| // SPDX-License-Identifier: GPL-2.0-only | 
 | /* | 
 |  * Generic support for sparse keymaps | 
 |  * | 
 |  * Copyright (c) 2009 Dmitry Torokhov | 
 |  * | 
 |  * Derived from wistron button driver: | 
 |  * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz> | 
 |  * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org> | 
 |  * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru> | 
 |  */ | 
 |  | 
 | #include <linux/input.h> | 
 | #include <linux/input/sparse-keymap.h> | 
 | #include <linux/module.h> | 
 | #include <linux/slab.h> | 
 |  | 
 | MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); | 
 | MODULE_DESCRIPTION("Generic support for sparse keymaps"); | 
 | MODULE_LICENSE("GPL v2"); | 
 |  | 
 | static unsigned int sparse_keymap_get_key_index(struct input_dev *dev, | 
 | 						const struct key_entry *k) | 
 | { | 
 | 	struct key_entry *key; | 
 | 	unsigned int idx = 0; | 
 |  | 
 | 	for (key = dev->keycode; key->type != KE_END; key++) { | 
 | 		if (key->type == KE_KEY) { | 
 | 			if (key == k) | 
 | 				break; | 
 | 			idx++; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return idx; | 
 | } | 
 |  | 
 | static struct key_entry *sparse_keymap_entry_by_index(struct input_dev *dev, | 
 | 						      unsigned int index) | 
 | { | 
 | 	struct key_entry *key; | 
 | 	unsigned int key_cnt = 0; | 
 |  | 
 | 	for (key = dev->keycode; key->type != KE_END; key++) | 
 | 		if (key->type == KE_KEY) | 
 | 			if (key_cnt++ == index) | 
 | 				return key; | 
 |  | 
 | 	return NULL; | 
 | } | 
 |  | 
 | /** | 
 |  * sparse_keymap_entry_from_scancode - perform sparse keymap lookup | 
 |  * @dev: Input device using sparse keymap | 
 |  * @code: Scan code | 
 |  * | 
 |  * This function is used to perform &struct key_entry lookup in an | 
 |  * input device using sparse keymap. | 
 |  */ | 
 | struct key_entry *sparse_keymap_entry_from_scancode(struct input_dev *dev, | 
 | 						    unsigned int code) | 
 | { | 
 | 	struct key_entry *key; | 
 |  | 
 | 	for (key = dev->keycode; key->type != KE_END; key++) | 
 | 		if (code == key->code) | 
 | 			return key; | 
 |  | 
 | 	return NULL; | 
 | } | 
 | EXPORT_SYMBOL(sparse_keymap_entry_from_scancode); | 
 |  | 
 | /** | 
 |  * sparse_keymap_entry_from_keycode - perform sparse keymap lookup | 
 |  * @dev: Input device using sparse keymap | 
 |  * @keycode: Key code | 
 |  * | 
 |  * This function is used to perform &struct key_entry lookup in an | 
 |  * input device using sparse keymap. | 
 |  */ | 
 | struct key_entry *sparse_keymap_entry_from_keycode(struct input_dev *dev, | 
 | 						   unsigned int keycode) | 
 | { | 
 | 	struct key_entry *key; | 
 |  | 
 | 	for (key = dev->keycode; key->type != KE_END; key++) | 
 | 		if (key->type == KE_KEY && keycode == key->keycode) | 
 | 			return key; | 
 |  | 
 | 	return NULL; | 
 | } | 
 | EXPORT_SYMBOL(sparse_keymap_entry_from_keycode); | 
 |  | 
 | static struct key_entry *sparse_keymap_locate(struct input_dev *dev, | 
 | 					const struct input_keymap_entry *ke) | 
 | { | 
 | 	struct key_entry *key; | 
 | 	unsigned int scancode; | 
 |  | 
 | 	if (ke->flags & INPUT_KEYMAP_BY_INDEX) | 
 | 		key = sparse_keymap_entry_by_index(dev, ke->index); | 
 | 	else if (input_scancode_to_scalar(ke, &scancode) == 0) | 
 | 		key = sparse_keymap_entry_from_scancode(dev, scancode); | 
 | 	else | 
 | 		key = NULL; | 
 |  | 
 | 	return key; | 
 | } | 
 |  | 
 | static int sparse_keymap_getkeycode(struct input_dev *dev, | 
 | 				    struct input_keymap_entry *ke) | 
 | { | 
 | 	const struct key_entry *key; | 
 |  | 
 | 	if (dev->keycode) { | 
 | 		key = sparse_keymap_locate(dev, ke); | 
 | 		if (key && key->type == KE_KEY) { | 
 | 			ke->keycode = key->keycode; | 
 | 			if (!(ke->flags & INPUT_KEYMAP_BY_INDEX)) | 
 | 				ke->index = | 
 | 					sparse_keymap_get_key_index(dev, key); | 
 | 			ke->len = sizeof(key->code); | 
 | 			memcpy(ke->scancode, &key->code, sizeof(key->code)); | 
 | 			return 0; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return -EINVAL; | 
 | } | 
 |  | 
 | static int sparse_keymap_setkeycode(struct input_dev *dev, | 
 | 				    const struct input_keymap_entry *ke, | 
 | 				    unsigned int *old_keycode) | 
 | { | 
 | 	struct key_entry *key; | 
 |  | 
 | 	if (dev->keycode) { | 
 | 		key = sparse_keymap_locate(dev, ke); | 
 | 		if (key && key->type == KE_KEY) { | 
 | 			*old_keycode = key->keycode; | 
 | 			key->keycode = ke->keycode; | 
 | 			set_bit(ke->keycode, dev->keybit); | 
 | 			if (!sparse_keymap_entry_from_keycode(dev, *old_keycode)) | 
 | 				clear_bit(*old_keycode, dev->keybit); | 
 | 			return 0; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return -EINVAL; | 
 | } | 
 |  | 
 | /** | 
 |  * sparse_keymap_setup - set up sparse keymap for an input device | 
 |  * @dev: Input device | 
 |  * @keymap: Keymap in form of array of &key_entry structures ending | 
 |  *	with %KE_END type entry | 
 |  * @setup: Function that can be used to adjust keymap entries | 
 |  *	depending on device's needs, may be %NULL | 
 |  * | 
 |  * The function calculates size and allocates copy of the original | 
 |  * keymap after which sets up input device event bits appropriately. | 
 |  * The allocated copy of the keymap is automatically freed when it | 
 |  * is no longer needed. | 
 |  */ | 
 | int sparse_keymap_setup(struct input_dev *dev, | 
 | 			const struct key_entry *keymap, | 
 | 			int (*setup)(struct input_dev *, struct key_entry *)) | 
 | { | 
 | 	size_t map_size = 1; /* to account for the last KE_END entry */ | 
 | 	const struct key_entry *e; | 
 | 	struct key_entry *map, *entry; | 
 | 	int i; | 
 | 	int error; | 
 |  | 
 | 	for (e = keymap; e->type != KE_END; e++) | 
 | 		map_size++; | 
 |  | 
 | 	map = devm_kmemdup(&dev->dev, keymap, map_size * sizeof(*map), | 
 | 			   GFP_KERNEL); | 
 | 	if (!map) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	for (i = 0; i < map_size; i++) { | 
 | 		entry = &map[i]; | 
 |  | 
 | 		if (setup) { | 
 | 			error = setup(dev, entry); | 
 | 			if (error) | 
 | 				return error; | 
 | 		} | 
 |  | 
 | 		switch (entry->type) { | 
 | 		case KE_KEY: | 
 | 			__set_bit(EV_KEY, dev->evbit); | 
 | 			__set_bit(entry->keycode, dev->keybit); | 
 | 			break; | 
 |  | 
 | 		case KE_SW: | 
 | 		case KE_VSW: | 
 | 			__set_bit(EV_SW, dev->evbit); | 
 | 			__set_bit(entry->sw.code, dev->swbit); | 
 | 			break; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (test_bit(EV_KEY, dev->evbit)) { | 
 | 		__set_bit(KEY_UNKNOWN, dev->keybit); | 
 | 		__set_bit(EV_MSC, dev->evbit); | 
 | 		__set_bit(MSC_SCAN, dev->mscbit); | 
 | 	} | 
 |  | 
 | 	dev->keycode = map; | 
 | 	dev->keycodemax = map_size; | 
 | 	dev->getkeycode = sparse_keymap_getkeycode; | 
 | 	dev->setkeycode = sparse_keymap_setkeycode; | 
 |  | 
 | 	return 0; | 
 | } | 
 | EXPORT_SYMBOL(sparse_keymap_setup); | 
 |  | 
 | /** | 
 |  * sparse_keymap_report_entry - report event corresponding to given key entry | 
 |  * @dev: Input device for which event should be reported | 
 |  * @ke: key entry describing event | 
 |  * @value: Value that should be reported (ignored by %KE_SW entries) | 
 |  * @autorelease: Signals whether release event should be emitted for %KE_KEY | 
 |  *	entries right after reporting press event, ignored by all other | 
 |  *	entries | 
 |  * | 
 |  * This function is used to report input event described by given | 
 |  * &struct key_entry. | 
 |  */ | 
 | void sparse_keymap_report_entry(struct input_dev *dev, const struct key_entry *ke, | 
 | 				unsigned int value, bool autorelease) | 
 | { | 
 | 	switch (ke->type) { | 
 | 	case KE_KEY: | 
 | 		input_event(dev, EV_MSC, MSC_SCAN, ke->code); | 
 | 		input_report_key(dev, ke->keycode, value); | 
 | 		input_sync(dev); | 
 | 		if (value && autorelease) { | 
 | 			input_report_key(dev, ke->keycode, 0); | 
 | 			input_sync(dev); | 
 | 		} | 
 | 		break; | 
 |  | 
 | 	case KE_SW: | 
 | 		value = ke->sw.value; | 
 | 		/* fall through */ | 
 |  | 
 | 	case KE_VSW: | 
 | 		input_report_switch(dev, ke->sw.code, value); | 
 | 		input_sync(dev); | 
 | 		break; | 
 | 	} | 
 | } | 
 | EXPORT_SYMBOL(sparse_keymap_report_entry); | 
 |  | 
 | /** | 
 |  * sparse_keymap_report_event - report event corresponding to given scancode | 
 |  * @dev: Input device using sparse keymap | 
 |  * @code: Scan code | 
 |  * @value: Value that should be reported (ignored by %KE_SW entries) | 
 |  * @autorelease: Signals whether release event should be emitted for %KE_KEY | 
 |  *	entries right after reporting press event, ignored by all other | 
 |  *	entries | 
 |  * | 
 |  * This function is used to perform lookup in an input device using sparse | 
 |  * keymap and report corresponding event. Returns %true if lookup was | 
 |  * successful and %false otherwise. | 
 |  */ | 
 | bool sparse_keymap_report_event(struct input_dev *dev, unsigned int code, | 
 | 				unsigned int value, bool autorelease) | 
 | { | 
 | 	const struct key_entry *ke = | 
 | 		sparse_keymap_entry_from_scancode(dev, code); | 
 | 	struct key_entry unknown_ke; | 
 |  | 
 | 	if (ke) { | 
 | 		sparse_keymap_report_entry(dev, ke, value, autorelease); | 
 | 		return true; | 
 | 	} | 
 |  | 
 | 	/* Report an unknown key event as a debugging aid */ | 
 | 	unknown_ke.type = KE_KEY; | 
 | 	unknown_ke.code = code; | 
 | 	unknown_ke.keycode = KEY_UNKNOWN; | 
 | 	sparse_keymap_report_entry(dev, &unknown_ke, value, true); | 
 |  | 
 | 	return false; | 
 | } | 
 | EXPORT_SYMBOL(sparse_keymap_report_event); | 
 |  |