diff options
Diffstat (limited to 'drivers/input/keycombo.c')
| -rw-r--r-- | drivers/input/keycombo.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/drivers/input/keycombo.c b/drivers/input/keycombo.c new file mode 100644 index 000000000000..2fba451b91d5 --- /dev/null +++ b/drivers/input/keycombo.c @@ -0,0 +1,261 @@ +/* drivers/input/keycombo.c + * + * Copyright (C) 2014 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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/keycombo.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> +#include <linux/sched.h> +#include <linux/slab.h> + +struct keycombo_state { + struct input_handler input_handler; + unsigned long keybit[BITS_TO_LONGS(KEY_CNT)]; + unsigned long upbit[BITS_TO_LONGS(KEY_CNT)]; + unsigned long key[BITS_TO_LONGS(KEY_CNT)]; + spinlock_t lock; + struct workqueue_struct *wq; + int key_down_target; + int key_down; + int key_up; + struct delayed_work key_down_work; + int delay; + struct work_struct key_up_work; + void (*key_up_fn)(void *); + void (*key_down_fn)(void *); + void *priv; + int key_is_down; + struct wakeup_source combo_held_wake_source; + struct wakeup_source combo_up_wake_source; +}; + +static void do_key_down(struct work_struct *work) +{ + struct delayed_work *dwork = container_of(work, struct delayed_work, + work); + struct keycombo_state *state = container_of(dwork, + struct keycombo_state, key_down_work); + if (state->key_down_fn) + state->key_down_fn(state->priv); +} + +static void do_key_up(struct work_struct *work) +{ + struct keycombo_state *state = container_of(work, struct keycombo_state, + key_up_work); + if (state->key_up_fn) + state->key_up_fn(state->priv); + __pm_relax(&state->combo_up_wake_source); +} + +static void keycombo_event(struct input_handle *handle, unsigned int type, + unsigned int code, int value) +{ + unsigned long flags; + struct keycombo_state *state = handle->private; + + if (type != EV_KEY) + return; + + if (code >= KEY_MAX) + return; + + if (!test_bit(code, state->keybit)) + return; + + spin_lock_irqsave(&state->lock, flags); + if (!test_bit(code, state->key) == !value) + goto done; + __change_bit(code, state->key); + if (test_bit(code, state->upbit)) { + if (value) + state->key_up++; + else + state->key_up--; + } else { + if (value) + state->key_down++; + else + state->key_down--; + } + if (state->key_down == state->key_down_target && state->key_up == 0) { + __pm_stay_awake(&state->combo_held_wake_source); + state->key_is_down = 1; + if (queue_delayed_work(state->wq, &state->key_down_work, + state->delay)) + pr_debug("Key down work already queued!"); + } else if (state->key_is_down) { + if (!cancel_delayed_work(&state->key_down_work)) { + __pm_stay_awake(&state->combo_up_wake_source); + queue_work(state->wq, &state->key_up_work); + } + __pm_relax(&state->combo_held_wake_source); + state->key_is_down = 0; + } +done: + spin_unlock_irqrestore(&state->lock, flags); +} + +static int keycombo_connect(struct input_handler *handler, + struct input_dev *dev, + const struct input_device_id *id) +{ + int i; + int ret; + struct input_handle *handle; + struct keycombo_state *state = + container_of(handler, struct keycombo_state, input_handler); + for (i = 0; i < KEY_MAX; i++) { + if (test_bit(i, state->keybit) && test_bit(i, dev->keybit)) + break; + } + if (i == KEY_MAX) + return -ENODEV; + + handle = kzalloc(sizeof(*handle), GFP_KERNEL); + if (!handle) + return -ENOMEM; + + handle->dev = dev; + handle->handler = handler; + handle->name = KEYCOMBO_NAME; + handle->private = state; + + ret = input_register_handle(handle); + if (ret) + goto err_input_register_handle; + + ret = input_open_device(handle); + if (ret) + goto err_input_open_device; + + return 0; + +err_input_open_device: + input_unregister_handle(handle); +err_input_register_handle: + kfree(handle); + return ret; +} + +static void keycombo_disconnect(struct input_handle *handle) +{ + input_close_device(handle); + input_unregister_handle(handle); + kfree(handle); +} + +static const struct input_device_id keycombo_ids[] = { + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT, + .evbit = { BIT_MASK(EV_KEY) }, + }, + { }, +}; +MODULE_DEVICE_TABLE(input, keycombo_ids); + +static int keycombo_probe(struct platform_device *pdev) +{ + int ret; + int key, *keyp; + struct keycombo_state *state; + struct keycombo_platform_data *pdata = pdev->dev.platform_data; + + if (!pdata) + return -EINVAL; + + state = kzalloc(sizeof(*state), GFP_KERNEL); + if (!state) + return -ENOMEM; + + spin_lock_init(&state->lock); + keyp = pdata->keys_down; + while ((key = *keyp++)) { + if (key >= KEY_MAX) + continue; + state->key_down_target++; + __set_bit(key, state->keybit); + } + if (pdata->keys_up) { + keyp = pdata->keys_up; + while ((key = *keyp++)) { + if (key >= KEY_MAX) + continue; + __set_bit(key, state->keybit); + __set_bit(key, state->upbit); + } + } + + state->wq = alloc_ordered_workqueue("keycombo", 0); + if (!state->wq) + return -ENOMEM; + + state->priv = pdata->priv; + + if (pdata->key_down_fn) + state->key_down_fn = pdata->key_down_fn; + INIT_DELAYED_WORK(&state->key_down_work, do_key_down); + + if (pdata->key_up_fn) + state->key_up_fn = pdata->key_up_fn; + INIT_WORK(&state->key_up_work, do_key_up); + + wakeup_source_init(&state->combo_held_wake_source, "key combo"); + wakeup_source_init(&state->combo_up_wake_source, "key combo up"); + state->delay = msecs_to_jiffies(pdata->key_down_delay); + + state->input_handler.event = keycombo_event; + state->input_handler.connect = keycombo_connect; + state->input_handler.disconnect = keycombo_disconnect; + state->input_handler.name = KEYCOMBO_NAME; + state->input_handler.id_table = keycombo_ids; + ret = input_register_handler(&state->input_handler); + if (ret) { + kfree(state); + return ret; + } + platform_set_drvdata(pdev, state); + return 0; +} + +int keycombo_remove(struct platform_device *pdev) +{ + struct keycombo_state *state = platform_get_drvdata(pdev); + input_unregister_handler(&state->input_handler); + destroy_workqueue(state->wq); + kfree(state); + return 0; +} + + +struct platform_driver keycombo_driver = { + .driver.name = KEYCOMBO_NAME, + .probe = keycombo_probe, + .remove = keycombo_remove, +}; + +static int __init keycombo_init(void) +{ + return platform_driver_register(&keycombo_driver); +} + +static void __exit keycombo_exit(void) +{ + return platform_driver_unregister(&keycombo_driver); +} + +module_init(keycombo_init); +module_exit(keycombo_exit); |