diff options
Diffstat (limited to 'drivers/input/sparse-keymap.c')
| -rw-r--r-- | drivers/input/sparse-keymap.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/drivers/input/sparse-keymap.c b/drivers/input/sparse-keymap.c new file mode 100644 index 00000000..75fb040a --- /dev/null +++ b/drivers/input/sparse-keymap.c @@ -0,0 +1,332 @@ +/* + * 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> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + */ + +#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"); +MODULE_VERSION("0.1"); + +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 deeds, may be %NULL + * + * The function calculates size and allocates copy of the original + * keymap after which sets up input device event bits appropriately. + * Before destroying input device allocated keymap should be freed + * with a call to sparse_keymap_free(). + */ +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 = kcalloc(map_size, sizeof (struct key_entry), GFP_KERNEL); + if (!map) + return -ENOMEM; + + memcpy(map, keymap, map_size * sizeof (struct key_entry)); + + for (i = 0; i < map_size; i++) { + entry = &map[i]; + + if (setup) { + error = setup(dev, entry); + if (error) + goto err_out; + } + + 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; + + err_out: + kfree(map); + return error; +} +EXPORT_SYMBOL(sparse_keymap_setup); + +/** + * sparse_keymap_free - free memory allocated for sparse keymap + * @dev: Input device using sparse keymap + * + * This function is used to free memory allocated by sparse keymap + * in an input device that was set up by sparse_keymap_setup(). + * NOTE: It is safe to cal this function while input device is + * still registered (however the drivers should care not to try to + * use freed keymap and thus have to shut off interrups/polling + * before freeing the keymap). + */ +void sparse_keymap_free(struct input_dev *dev) +{ + unsigned long flags; + + /* + * Take event lock to prevent racing with input_get_keycode() + * and input_set_keycode() if we are called while input device + * is still registered. + */ + spin_lock_irqsave(&dev->event_lock, flags); + + kfree(dev->keycode); + dev->keycode = NULL; + dev->keycodemax = 0; + + spin_unlock_irqrestore(&dev->event_lock, flags); +} +EXPORT_SYMBOL(sparse_keymap_free); + +/** + * 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); + 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); + |