input.c 58.8 KB
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/*
 * The input core
 *
 * Copyright (c) 1999-2002 Vojtech Pavlik
 */

/*
 * 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.
 */

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#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt

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#include <linux/init.h>
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#include <linux/types.h>
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#include <linux/idr.h>
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#include <linux/input/mt.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/random.h>
#include <linux/major.h>
#include <linux/proc_fs.h>
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#include <linux/sched.h>
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#include <linux/seq_file.h>
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#include <linux/poll.h>
#include <linux/device.h>
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#include <linux/mutex.h>
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#include <linux/rcupdate.h>
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#include "input-compat.h"
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MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
MODULE_DESCRIPTION("Input core");
MODULE_LICENSE("GPL");

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#define INPUT_MAX_CHAR_DEVICES		1024
#define INPUT_FIRST_DYNAMIC_DEV		256
static DEFINE_IDA(input_ida);
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static LIST_HEAD(input_dev_list);
static LIST_HEAD(input_handler_list);

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/*
 * input_mutex protects access to both input_dev_list and input_handler_list.
 * This also causes input_[un]register_device and input_[un]register_handler
 * be mutually exclusive which simplifies locking in drivers implementing
 * input handlers.
 */
static DEFINE_MUTEX(input_mutex);

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static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };

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static inline int is_event_supported(unsigned int code,
				     unsigned long *bm, unsigned int max)
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{
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	return code <= max && test_bit(code, bm);
}
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static int input_defuzz_abs_event(int value, int old_val, int fuzz)
{
	if (fuzz) {
		if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
			return old_val;
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		if (value > old_val - fuzz && value < old_val + fuzz)
			return (old_val * 3 + value) / 4;
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		if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
			return (old_val + value) / 2;
	}
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	return value;
}
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static void input_start_autorepeat(struct input_dev *dev, int code)
{
	if (test_bit(EV_REP, dev->evbit) &&
	    dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
	    dev->timer.data) {
		dev->repeat_key = code;
		mod_timer(&dev->timer,
			  jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
	}
}

static void input_stop_autorepeat(struct input_dev *dev)
{
	del_timer(&dev->timer);
}

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/*
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 * Pass event first through all filters and then, if event has not been
 * filtered out, through all open handles. This function is called with
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 * dev->event_lock held and interrupts disabled.
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 */
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static unsigned int input_to_handler(struct input_handle *handle,
			struct input_value *vals, unsigned int count)
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{
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	struct input_handler *handler = handle->handler;
	struct input_value *end = vals;
	struct input_value *v;
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	for (v = vals; v != vals + count; v++) {
		if (handler->filter &&
		    handler->filter(handle, v->type, v->code, v->value))
			continue;
		if (end != v)
			*end = *v;
		end++;
	}
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	count = end - vals;
	if (!count)
		return 0;
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	if (handler->events)
		handler->events(handle, vals, count);
	else if (handler->event)
		for (v = vals; v != end; v++)
			handler->event(handle, v->type, v->code, v->value);
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	return count;
}
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/*
 * Pass values first through all filters and then, if event has not been
 * filtered out, through all open handles. This function is called with
 * dev->event_lock held and interrupts disabled.
 */
static void input_pass_values(struct input_dev *dev,
			      struct input_value *vals, unsigned int count)
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{
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	struct input_handle *handle;
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	struct input_value *v;
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	if (!count)
		return;
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	rcu_read_lock();
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	handle = rcu_dereference(dev->grab);
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	if (handle) {
		count = input_to_handler(handle, vals, count);
	} else {
		list_for_each_entry_rcu(handle, &dev->h_list, d_node)
			if (handle->open)
				count = input_to_handler(handle, vals, count);
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	}

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	rcu_read_unlock();
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	add_input_randomness(vals->type, vals->code, vals->value);
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	/* trigger auto repeat for key events */
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	for (v = vals; v != vals + count; v++) {
		if (v->type == EV_KEY && v->value != 2) {
			if (v->value)
				input_start_autorepeat(dev, v->code);
			else
				input_stop_autorepeat(dev);
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		}
	}
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}
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static void input_pass_event(struct input_dev *dev,
			     unsigned int type, unsigned int code, int value)
{
	struct input_value vals[] = { { type, code, value } };

	input_pass_values(dev, vals, ARRAY_SIZE(vals));
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}
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/*
 * Generate software autorepeat event. Note that we take
 * dev->event_lock here to avoid racing with input_event
 * which may cause keys get "stuck".
 */
static void input_repeat_key(unsigned long data)
{
	struct input_dev *dev = (void *) data;
	unsigned long flags;
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	spin_lock_irqsave(&dev->event_lock, flags);
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	if (test_bit(dev->repeat_key, dev->key) &&
	    is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
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		struct input_value vals[] =  {
			{ EV_KEY, dev->repeat_key, 2 },
			input_value_sync
		};
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		input_pass_values(dev, vals, ARRAY_SIZE(vals));
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		if (dev->rep[REP_PERIOD])
			mod_timer(&dev->timer, jiffies +
					msecs_to_jiffies(dev->rep[REP_PERIOD]));
	}
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	spin_unlock_irqrestore(&dev->event_lock, flags);
}
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#define INPUT_IGNORE_EVENT	0
#define INPUT_PASS_TO_HANDLERS	1
#define INPUT_PASS_TO_DEVICE	2
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#define INPUT_SLOT		4
#define INPUT_FLUSH		8
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#define INPUT_PASS_TO_ALL	(INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
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static int input_handle_abs_event(struct input_dev *dev,
				  unsigned int code, int *pval)
{
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	struct input_mt *mt = dev->mt;
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	bool is_mt_event;
	int *pold;

	if (code == ABS_MT_SLOT) {
		/*
		 * "Stage" the event; we'll flush it later, when we
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		 * get actual touch data.
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		 */
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		if (mt && *pval >= 0 && *pval < mt->num_slots)
			mt->slot = *pval;
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		return INPUT_IGNORE_EVENT;
	}

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	is_mt_event = input_is_mt_value(code);
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	if (!is_mt_event) {
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		pold = &dev->absinfo[code].value;
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	} else if (mt) {
		pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
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	} else {
		/*
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		 * Bypass filtering for multi-touch events when
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		 * not employing slots.
		 */
		pold = NULL;
	}

	if (pold) {
		*pval = input_defuzz_abs_event(*pval, *pold,
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						dev->absinfo[code].fuzz);
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		if (*pold == *pval)
			return INPUT_IGNORE_EVENT;

		*pold = *pval;
	}

	/* Flush pending "slot" event */
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	if (is_mt_event && mt && mt->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
		input_abs_set_val(dev, ABS_MT_SLOT, mt->slot);
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		return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
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	}

	return INPUT_PASS_TO_HANDLERS;
}

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static int input_get_disposition(struct input_dev *dev,
			  unsigned int type, unsigned int code, int value)
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{
	int disposition = INPUT_IGNORE_EVENT;
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	switch (type) {
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	case EV_SYN:
		switch (code) {
		case SYN_CONFIG:
			disposition = INPUT_PASS_TO_ALL;
			break;
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		case SYN_REPORT:
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			disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
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			break;
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		case SYN_MT_REPORT:
			disposition = INPUT_PASS_TO_HANDLERS;
			break;
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		}
		break;
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	case EV_KEY:
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		if (is_event_supported(code, dev->keybit, KEY_MAX)) {
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			/* auto-repeat bypasses state updates */
			if (value == 2) {
				disposition = INPUT_PASS_TO_HANDLERS;
				break;
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			}
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			if (!!test_bit(code, dev->key) != !!value) {
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				__change_bit(code, dev->key);
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				disposition = INPUT_PASS_TO_HANDLERS;
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			}
		}
		break;
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	case EV_SW:
		if (is_event_supported(code, dev->swbit, SW_MAX) &&
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		    !!test_bit(code, dev->sw) != !!value) {
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			__change_bit(code, dev->sw);
			disposition = INPUT_PASS_TO_HANDLERS;
		}
		break;
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	case EV_ABS:
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		if (is_event_supported(code, dev->absbit, ABS_MAX))
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			disposition = input_handle_abs_event(dev, code, &value);
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		break;
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	case EV_REL:
		if (is_event_supported(code, dev->relbit, REL_MAX) && value)
			disposition = INPUT_PASS_TO_HANDLERS;
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		break;
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	case EV_MSC:
		if (is_event_supported(code, dev->mscbit, MSC_MAX))
			disposition = INPUT_PASS_TO_ALL;
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		break;
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	case EV_LED:
		if (is_event_supported(code, dev->ledbit, LED_MAX) &&
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		    !!test_bit(code, dev->led) != !!value) {
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			__change_bit(code, dev->led);
			disposition = INPUT_PASS_TO_ALL;
		}
		break;

	case EV_SND:
		if (is_event_supported(code, dev->sndbit, SND_MAX)) {
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			if (!!test_bit(code, dev->snd) != !!value)
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				__change_bit(code, dev->snd);
			disposition = INPUT_PASS_TO_ALL;
		}
		break;
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	case EV_REP:
		if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
			dev->rep[code] = value;
			disposition = INPUT_PASS_TO_ALL;
		}
		break;
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	case EV_FF:
		if (value >= 0)
			disposition = INPUT_PASS_TO_ALL;
		break;
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	case EV_PWR:
		disposition = INPUT_PASS_TO_ALL;
		break;
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	}
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	return disposition;
}

static void input_handle_event(struct input_dev *dev,
			       unsigned int type, unsigned int code, int value)
{
	int disposition;

	disposition = input_get_disposition(dev, type, code, value);
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	if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
		dev->event(dev, type, code, value);
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	if (!dev->vals)
		return;

	if (disposition & INPUT_PASS_TO_HANDLERS) {
		struct input_value *v;

		if (disposition & INPUT_SLOT) {
			v = &dev->vals[dev->num_vals++];
			v->type = EV_ABS;
			v->code = ABS_MT_SLOT;
			v->value = dev->mt->slot;
		}

		v = &dev->vals[dev->num_vals++];
		v->type = type;
		v->code = code;
		v->value = value;
	}

	if (disposition & INPUT_FLUSH) {
		if (dev->num_vals >= 2)
			input_pass_values(dev, dev->vals, dev->num_vals);
		dev->num_vals = 0;
	} else if (dev->num_vals >= dev->max_vals - 2) {
		dev->vals[dev->num_vals++] = input_value_sync;
		input_pass_values(dev, dev->vals, dev->num_vals);
		dev->num_vals = 0;
	}

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}
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/**
 * input_event() - report new input event
 * @dev: device that generated the event
 * @type: type of the event
 * @code: event code
 * @value: value of the event
 *
 * This function should be used by drivers implementing various input
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 * devices to report input events. See also input_inject_event().
 *
 * NOTE: input_event() may be safely used right after input device was
 * allocated with input_allocate_device(), even before it is registered
 * with input_register_device(), but the event will not reach any of the
 * input handlers. Such early invocation of input_event() may be used
 * to 'seed' initial state of a switch or initial position of absolute
 * axis, etc.
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 */
void input_event(struct input_dev *dev,
		 unsigned int type, unsigned int code, int value)
{
	unsigned long flags;
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	if (is_event_supported(type, dev->evbit, EV_MAX)) {
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		spin_lock_irqsave(&dev->event_lock, flags);
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		input_handle_event(dev, type, code, value);
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		spin_unlock_irqrestore(&dev->event_lock, flags);
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	}
}
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EXPORT_SYMBOL(input_event);
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/**
 * input_inject_event() - send input event from input handler
 * @handle: input handle to send event through
 * @type: type of the event
 * @code: event code
 * @value: value of the event
 *
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 * Similar to input_event() but will ignore event if device is
 * "grabbed" and handle injecting event is not the one that owns
 * the device.
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 */
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void input_inject_event(struct input_handle *handle,
			unsigned int type, unsigned int code, int value)
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{
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	struct input_dev *dev = handle->dev;
	struct input_handle *grab;
	unsigned long flags;
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	if (is_event_supported(type, dev->evbit, EV_MAX)) {
		spin_lock_irqsave(&dev->event_lock, flags);
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		rcu_read_lock();
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		grab = rcu_dereference(dev->grab);
		if (!grab || grab == handle)
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			input_handle_event(dev, type, code, value);
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		rcu_read_unlock();
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		spin_unlock_irqrestore(&dev->event_lock, flags);
	}
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}
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EXPORT_SYMBOL(input_inject_event);
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/**
 * input_alloc_absinfo - allocates array of input_absinfo structs
 * @dev: the input device emitting absolute events
 *
 * If the absinfo struct the caller asked for is already allocated, this
 * functions will not do anything.
 */
void input_alloc_absinfo(struct input_dev *dev)
{
	if (!dev->absinfo)
		dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
					GFP_KERNEL);

	WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
}
EXPORT_SYMBOL(input_alloc_absinfo);

void input_set_abs_params(struct input_dev *dev, unsigned int axis,
			  int min, int max, int fuzz, int flat)
{
	struct input_absinfo *absinfo;

	input_alloc_absinfo(dev);
	if (!dev->absinfo)
		return;

	absinfo = &dev->absinfo[axis];
	absinfo->minimum = min;
	absinfo->maximum = max;
	absinfo->fuzz = fuzz;
	absinfo->flat = flat;

	dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
}
EXPORT_SYMBOL(input_set_abs_params);


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/**
 * input_grab_device - grabs device for exclusive use
 * @handle: input handle that wants to own the device
 *
 * When a device is grabbed by an input handle all events generated by
 * the device are delivered only to this handle. Also events injected
 * by other input handles are ignored while device is grabbed.
 */
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int input_grab_device(struct input_handle *handle)
{
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	struct input_dev *dev = handle->dev;
	int retval;
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	retval = mutex_lock_interruptible(&dev->mutex);
	if (retval)
		return retval;

	if (dev->grab) {
		retval = -EBUSY;
		goto out;
	}

	rcu_assign_pointer(dev->grab, handle);

 out:
	mutex_unlock(&dev->mutex);
	return retval;
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}
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EXPORT_SYMBOL(input_grab_device);
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static void __input_release_device(struct input_handle *handle)
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{
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	struct input_dev *dev = handle->dev;
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	struct input_handle *grabber;
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	grabber = rcu_dereference_protected(dev->grab,
					    lockdep_is_held(&dev->mutex));
	if (grabber == handle) {
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		rcu_assign_pointer(dev->grab, NULL);
		/* Make sure input_pass_event() notices that grab is gone */
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		synchronize_rcu();
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		list_for_each_entry(handle, &dev->h_list, d_node)
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			if (handle->open && handle->handler->start)
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				handle->handler->start(handle);
	}
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}
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/**
 * input_release_device - release previously grabbed device
 * @handle: input handle that owns the device
 *
 * Releases previously grabbed device so that other input handles can
 * start receiving input events. Upon release all handlers attached
 * to the device have their start() method called so they have a change
 * to synchronize device state with the rest of the system.
 */
void input_release_device(struct input_handle *handle)
{
	struct input_dev *dev = handle->dev;

	mutex_lock(&dev->mutex);
	__input_release_device(handle);
	mutex_unlock(&dev->mutex);
}
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EXPORT_SYMBOL(input_release_device);
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/**
 * input_open_device - open input device
 * @handle: handle through which device is being accessed
 *
 * This function should be called by input handlers when they
 * want to start receive events from given input device.
 */
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int input_open_device(struct input_handle *handle)
{
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	struct input_dev *dev = handle->dev;
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	int retval;
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	retval = mutex_lock_interruptible(&dev->mutex);
	if (retval)
		return retval;

	if (dev->going_away) {
		retval = -ENODEV;
		goto out;
	}
591

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592
	handle->open++;
593 594

	if (!dev->users++ && dev->open)
595 596 597 598 599 600 601 602 603
		retval = dev->open(dev);

	if (retval) {
		dev->users--;
		if (!--handle->open) {
			/*
			 * Make sure we are not delivering any more events
			 * through this handle
			 */
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Dmitry Torokhov 已提交
604
			synchronize_rcu();
605 606
		}
	}
607

608
 out:
609
	mutex_unlock(&dev->mutex);
610
	return retval;
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611
}
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612
EXPORT_SYMBOL(input_open_device);
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613

614
int input_flush_device(struct input_handle *handle, struct file *file)
L
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615
{
616 617
	struct input_dev *dev = handle->dev;
	int retval;
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618

619 620 621 622 623 624 625 626 627
	retval = mutex_lock_interruptible(&dev->mutex);
	if (retval)
		return retval;

	if (dev->flush)
		retval = dev->flush(dev, file);

	mutex_unlock(&dev->mutex);
	return retval;
L
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628
}
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Dmitry Torokhov 已提交
629
EXPORT_SYMBOL(input_flush_device);
L
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630

631 632 633 634 635 636 637
/**
 * input_close_device - close input device
 * @handle: handle through which device is being accessed
 *
 * This function should be called by input handlers when they
 * want to stop receive events from given input device.
 */
L
Linus Torvalds 已提交
638 639
void input_close_device(struct input_handle *handle)
{
640 641
	struct input_dev *dev = handle->dev;

642
	mutex_lock(&dev->mutex);
643

644 645
	__input_release_device(handle);

646 647
	if (!--dev->users && dev->close)
		dev->close(dev);
648 649 650

	if (!--handle->open) {
		/*
D
Dmitry Torokhov 已提交
651
		 * synchronize_rcu() makes sure that input_pass_event()
652 653 654
		 * completed and that no more input events are delivered
		 * through this handle
		 */
D
Dmitry Torokhov 已提交
655
		synchronize_rcu();
656
	}
657

658
	mutex_unlock(&dev->mutex);
L
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659
}
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660
EXPORT_SYMBOL(input_close_device);
L
Linus Torvalds 已提交
661

662 663 664 665 666 667 668 669 670 671 672 673
/*
 * Simulate keyup events for all keys that are marked as pressed.
 * The function must be called with dev->event_lock held.
 */
static void input_dev_release_keys(struct input_dev *dev)
{
	int code;

	if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
		for (code = 0; code <= KEY_MAX; code++) {
			if (is_event_supported(code, dev->keybit, KEY_MAX) &&
			    __test_and_clear_bit(code, dev->key)) {
674
				input_pass_event(dev, EV_KEY, code, 0);
675 676
			}
		}
677
		input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
678 679 680
	}
}

681 682 683 684 685 686 687 688 689 690 691 692 693
/*
 * Prepare device for unregistering
 */
static void input_disconnect_device(struct input_dev *dev)
{
	struct input_handle *handle;

	/*
	 * Mark device as going away. Note that we take dev->mutex here
	 * not to protect access to dev->going_away but rather to ensure
	 * that there are no threads in the middle of input_open_device()
	 */
	mutex_lock(&dev->mutex);
694
	dev->going_away = true;
695 696 697 698 699 700 701 702 703 704
	mutex_unlock(&dev->mutex);

	spin_lock_irq(&dev->event_lock);

	/*
	 * Simulate keyup events for all pressed keys so that handlers
	 * are not left with "stuck" keys. The driver may continue
	 * generate events even after we done here but they will not
	 * reach any handlers.
	 */
705
	input_dev_release_keys(dev);
706 707 708 709 710 711 712

	list_for_each_entry(handle, &dev->h_list, d_node)
		handle->open = 0;

	spin_unlock_irq(&dev->event_lock);
}

713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753
/**
 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
 * @ke: keymap entry containing scancode to be converted.
 * @scancode: pointer to the location where converted scancode should
 *	be stored.
 *
 * This function is used to convert scancode stored in &struct keymap_entry
 * into scalar form understood by legacy keymap handling methods. These
 * methods expect scancodes to be represented as 'unsigned int'.
 */
int input_scancode_to_scalar(const struct input_keymap_entry *ke,
			     unsigned int *scancode)
{
	switch (ke->len) {
	case 1:
		*scancode = *((u8 *)ke->scancode);
		break;

	case 2:
		*scancode = *((u16 *)ke->scancode);
		break;

	case 4:
		*scancode = *((u32 *)ke->scancode);
		break;

	default:
		return -EINVAL;
	}

	return 0;
}
EXPORT_SYMBOL(input_scancode_to_scalar);

/*
 * Those routines handle the default case where no [gs]etkeycode() is
 * defined. In this case, an array indexed by the scancode is used.
 */

static unsigned int input_fetch_keycode(struct input_dev *dev,
					unsigned int index)
754 755
{
	switch (dev->keycodesize) {
756 757
	case 1:
		return ((u8 *)dev->keycode)[index];
758

759 760
	case 2:
		return ((u16 *)dev->keycode)[index];
761

762 763
	default:
		return ((u32 *)dev->keycode)[index];
764 765 766 767
	}
}

static int input_default_getkeycode(struct input_dev *dev,
768
				    struct input_keymap_entry *ke)
769
{
770 771 772
	unsigned int index;
	int error;

773 774 775
	if (!dev->keycodesize)
		return -EINVAL;

776 777 778 779 780 781 782 783 784
	if (ke->flags & INPUT_KEYMAP_BY_INDEX)
		index = ke->index;
	else {
		error = input_scancode_to_scalar(ke, &index);
		if (error)
			return error;
	}

	if (index >= dev->keycodemax)
785 786
		return -EINVAL;

787 788 789 790
	ke->keycode = input_fetch_keycode(dev, index);
	ke->index = index;
	ke->len = sizeof(index);
	memcpy(ke->scancode, &index, sizeof(index));
791 792 793 794 795

	return 0;
}

static int input_default_setkeycode(struct input_dev *dev,
796 797
				    const struct input_keymap_entry *ke,
				    unsigned int *old_keycode)
798
{
799 800
	unsigned int index;
	int error;
801 802
	int i;

803
	if (!dev->keycodesize)
804 805
		return -EINVAL;

806 807 808 809 810 811 812 813 814
	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
		index = ke->index;
	} else {
		error = input_scancode_to_scalar(ke, &index);
		if (error)
			return error;
	}

	if (index >= dev->keycodemax)
815 816
		return -EINVAL;

817
	if (dev->keycodesize < sizeof(ke->keycode) &&
818
			(ke->keycode >> (dev->keycodesize * 8)))
819 820 821 822 823
		return -EINVAL;

	switch (dev->keycodesize) {
		case 1: {
			u8 *k = (u8 *)dev->keycode;
824 825
			*old_keycode = k[index];
			k[index] = ke->keycode;
826 827 828 829
			break;
		}
		case 2: {
			u16 *k = (u16 *)dev->keycode;
830 831
			*old_keycode = k[index];
			k[index] = ke->keycode;
832 833 834 835
			break;
		}
		default: {
			u32 *k = (u32 *)dev->keycode;
836 837
			*old_keycode = k[index];
			k[index] = ke->keycode;
838 839 840 841
			break;
		}
	}

842 843
	__clear_bit(*old_keycode, dev->keybit);
	__set_bit(ke->keycode, dev->keybit);
844 845

	for (i = 0; i < dev->keycodemax; i++) {
846 847
		if (input_fetch_keycode(dev, i) == *old_keycode) {
			__set_bit(*old_keycode, dev->keybit);
848 849 850 851 852 853 854
			break; /* Setting the bit twice is useless, so break */
		}
	}

	return 0;
}

855 856 857
/**
 * input_get_keycode - retrieve keycode currently mapped to a given scancode
 * @dev: input device which keymap is being queried
858
 * @ke: keymap entry
859 860
 *
 * This function should be called by anyone interested in retrieving current
861
 * keymap. Presently evdev handlers use it.
862
 */
863
int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
864
{
865 866 867 868
	unsigned long flags;
	int retval;

	spin_lock_irqsave(&dev->event_lock, flags);
869
	retval = dev->getkeycode(dev, ke);
870
	spin_unlock_irqrestore(&dev->event_lock, flags);
871

872
	return retval;
873 874 875 876
}
EXPORT_SYMBOL(input_get_keycode);

/**
877
 * input_set_keycode - attribute a keycode to a given scancode
878
 * @dev: input device which keymap is being updated
879
 * @ke: new keymap entry
880 881 882 883
 *
 * This function should be called by anyone needing to update current
 * keymap. Presently keyboard and evdev handlers use it.
 */
884
int input_set_keycode(struct input_dev *dev,
885
		      const struct input_keymap_entry *ke)
886 887
{
	unsigned long flags;
888
	unsigned int old_keycode;
889 890
	int retval;

891
	if (ke->keycode > KEY_MAX)
892 893 894 895
		return -EINVAL;

	spin_lock_irqsave(&dev->event_lock, flags);

896
	retval = dev->setkeycode(dev, ke, &old_keycode);
897 898 899
	if (retval)
		goto out;

900 901 902
	/* Make sure KEY_RESERVED did not get enabled. */
	__clear_bit(KEY_RESERVED, dev->keybit);

903 904 905 906 907 908 909
	/*
	 * Simulate keyup event if keycode is not present
	 * in the keymap anymore
	 */
	if (test_bit(EV_KEY, dev->evbit) &&
	    !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
	    __test_and_clear_bit(old_keycode, dev->key)) {
910 911 912 913
		struct input_value vals[] =  {
			{ EV_KEY, old_keycode, 0 },
			input_value_sync
		};
914

915
		input_pass_values(dev, vals, ARRAY_SIZE(vals));
916 917 918 919 920 921 922 923
	}

 out:
	spin_unlock_irqrestore(&dev->event_lock, flags);

	return retval;
}
EXPORT_SYMBOL(input_set_keycode);
924

925
static const struct input_device_id *input_match_device(struct input_handler *handler,
D
Dmitry Torokhov 已提交
926
							struct input_dev *dev)
L
Linus Torvalds 已提交
927
{
928
	const struct input_device_id *id;
L
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929

930
	for (id = handler->id_table; id->flags || id->driver_info; id++) {
L
Linus Torvalds 已提交
931 932

		if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
933
			if (id->bustype != dev->id.bustype)
L
Linus Torvalds 已提交
934 935 936
				continue;

		if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
937
			if (id->vendor != dev->id.vendor)
L
Linus Torvalds 已提交
938 939 940
				continue;

		if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
941
			if (id->product != dev->id.product)
L
Linus Torvalds 已提交
942 943 944
				continue;

		if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
945
			if (id->version != dev->id.version)
L
Linus Torvalds 已提交
946 947
				continue;

948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973
		if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX))
			continue;

		if (!bitmap_subset(id->keybit, dev->keybit, KEY_MAX))
			continue;

		if (!bitmap_subset(id->relbit, dev->relbit, REL_MAX))
			continue;

		if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX))
			continue;

		if (!bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX))
			continue;

		if (!bitmap_subset(id->ledbit, dev->ledbit, LED_MAX))
			continue;

		if (!bitmap_subset(id->sndbit, dev->sndbit, SND_MAX))
			continue;

		if (!bitmap_subset(id->ffbit, dev->ffbit, FF_MAX))
			continue;

		if (!bitmap_subset(id->swbit, dev->swbit, SW_MAX))
			continue;
L
Linus Torvalds 已提交
974

975 976
		if (!handler->match || handler->match(handler, dev))
			return id;
L
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977 978 979 980 981
	}

	return NULL;
}

982 983 984 985 986
static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
{
	const struct input_device_id *id;
	int error;

987
	id = input_match_device(handler, dev);
988 989 990 991 992
	if (!id)
		return -ENODEV;

	error = handler->connect(handler, dev, id);
	if (error && error != -ENODEV)
J
Joe Perches 已提交
993 994
		pr_err("failed to attach handler %s to device %s, error: %d\n",
		       handler->name, kobject_name(&dev->dev.kobj), error);
995 996 997 998

	return error;
}

999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032
#ifdef CONFIG_COMPAT

static int input_bits_to_string(char *buf, int buf_size,
				unsigned long bits, bool skip_empty)
{
	int len = 0;

	if (INPUT_COMPAT_TEST) {
		u32 dword = bits >> 32;
		if (dword || !skip_empty)
			len += snprintf(buf, buf_size, "%x ", dword);

		dword = bits & 0xffffffffUL;
		if (dword || !skip_empty || len)
			len += snprintf(buf + len, max(buf_size - len, 0),
					"%x", dword);
	} else {
		if (bits || !skip_empty)
			len += snprintf(buf, buf_size, "%lx", bits);
	}

	return len;
}

#else /* !CONFIG_COMPAT */

static int input_bits_to_string(char *buf, int buf_size,
				unsigned long bits, bool skip_empty)
{
	return bits || !skip_empty ?
		snprintf(buf, buf_size, "%lx", bits) : 0;
}

#endif
1033

1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045
#ifdef CONFIG_PROC_FS

static struct proc_dir_entry *proc_bus_input_dir;
static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
static int input_devices_state;

static inline void input_wakeup_procfs_readers(void)
{
	input_devices_state++;
	wake_up(&input_devices_poll_wait);
}

1046
static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1047 1048
{
	poll_wait(file, &input_devices_poll_wait, wait);
1049 1050
	if (file->f_version != input_devices_state) {
		file->f_version = input_devices_state;
1051
		return POLLIN | POLLRDNORM;
1052
	}
1053

1054 1055 1056
	return 0;
}

1057 1058 1059 1060 1061 1062 1063 1064
union input_seq_state {
	struct {
		unsigned short pos;
		bool mutex_acquired;
	};
	void *p;
};

1065 1066
static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
{
1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079
	union input_seq_state *state = (union input_seq_state *)&seq->private;
	int error;

	/* We need to fit into seq->private pointer */
	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));

	error = mutex_lock_interruptible(&input_mutex);
	if (error) {
		state->mutex_acquired = false;
		return ERR_PTR(error);
	}

	state->mutex_acquired = true;
1080

1081
	return seq_list_start(&input_dev_list, *pos);
1082
}
1083

1084 1085
static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
1086
	return seq_list_next(v, &input_dev_list, pos);
1087
}
1088

1089
static void input_seq_stop(struct seq_file *seq, void *v)
1090
{
1091 1092 1093 1094
	union input_seq_state *state = (union input_seq_state *)&seq->private;

	if (state->mutex_acquired)
		mutex_unlock(&input_mutex);
1095
}
1096

1097 1098 1099 1100
static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
				   unsigned long *bitmap, int max)
{
	int i;
1101 1102
	bool skip_empty = true;
	char buf[18];
1103

1104
	seq_printf(seq, "B: %s=", name);
1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119

	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
		if (input_bits_to_string(buf, sizeof(buf),
					 bitmap[i], skip_empty)) {
			skip_empty = false;
			seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
		}
	}

	/*
	 * If no output was produced print a single 0.
	 */
	if (skip_empty)
		seq_puts(seq, "0");

1120 1121
	seq_putc(seq, '\n');
}
1122

1123 1124 1125
static int input_devices_seq_show(struct seq_file *seq, void *v)
{
	struct input_dev *dev = container_of(v, struct input_dev, node);
1126
	const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1127 1128 1129 1130 1131 1132 1133 1134
	struct input_handle *handle;

	seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
		   dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);

	seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
	seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
	seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1135
	seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1136 1137 1138 1139 1140 1141
	seq_printf(seq, "H: Handlers=");

	list_for_each_entry(handle, &dev->h_list, d_node)
		seq_printf(seq, "%s ", handle->name);
	seq_putc(seq, '\n');

1142 1143
	input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);

1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165
	input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
	if (test_bit(EV_KEY, dev->evbit))
		input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
	if (test_bit(EV_REL, dev->evbit))
		input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
	if (test_bit(EV_ABS, dev->evbit))
		input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
	if (test_bit(EV_MSC, dev->evbit))
		input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
	if (test_bit(EV_LED, dev->evbit))
		input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
	if (test_bit(EV_SND, dev->evbit))
		input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
	if (test_bit(EV_FF, dev->evbit))
		input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
	if (test_bit(EV_SW, dev->evbit))
		input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);

	seq_putc(seq, '\n');

	kfree(path);
	return 0;
1166 1167
}

1168
static const struct seq_operations input_devices_seq_ops = {
1169 1170
	.start	= input_devices_seq_start,
	.next	= input_devices_seq_next,
1171
	.stop	= input_seq_stop,
1172 1173 1174 1175
	.show	= input_devices_seq_show,
};

static int input_proc_devices_open(struct inode *inode, struct file *file)
1176
{
1177 1178 1179
	return seq_open(file, &input_devices_seq_ops);
}

1180
static const struct file_operations input_devices_fileops = {
1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
	.owner		= THIS_MODULE,
	.open		= input_proc_devices_open,
	.poll		= input_proc_devices_poll,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
{
1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204
	union input_seq_state *state = (union input_seq_state *)&seq->private;
	int error;

	/* We need to fit into seq->private pointer */
	BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));

	error = mutex_lock_interruptible(&input_mutex);
	if (error) {
		state->mutex_acquired = false;
		return ERR_PTR(error);
	}

	state->mutex_acquired = true;
	state->pos = *pos;
1205

1206
	return seq_list_start(&input_handler_list, *pos);
1207
}
1208

1209 1210
static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
1211
	union input_seq_state *state = (union input_seq_state *)&seq->private;
1212

1213 1214
	state->pos = *pos + 1;
	return seq_list_next(v, &input_handler_list, pos);
1215 1216 1217 1218 1219
}

static int input_handlers_seq_show(struct seq_file *seq, void *v)
{
	struct input_handler *handler = container_of(v, struct input_handler, node);
1220
	union input_seq_state *state = (union input_seq_state *)&seq->private;
1221

1222
	seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
D
Dmitry Torokhov 已提交
1223 1224
	if (handler->filter)
		seq_puts(seq, " (filter)");
1225
	if (handler->legacy_minors)
1226 1227 1228 1229 1230
		seq_printf(seq, " Minor=%d", handler->minor);
	seq_putc(seq, '\n');

	return 0;
}
1231

1232
static const struct seq_operations input_handlers_seq_ops = {
1233 1234
	.start	= input_handlers_seq_start,
	.next	= input_handlers_seq_next,
1235
	.stop	= input_seq_stop,
1236 1237 1238 1239 1240 1241 1242 1243
	.show	= input_handlers_seq_show,
};

static int input_proc_handlers_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &input_handlers_seq_ops);
}

1244
static const struct file_operations input_handlers_fileops = {
1245 1246 1247 1248 1249 1250
	.owner		= THIS_MODULE,
	.open		= input_proc_handlers_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};
1251 1252 1253 1254 1255

static int __init input_proc_init(void)
{
	struct proc_dir_entry *entry;

A
Alexey Dobriyan 已提交
1256
	proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1257 1258 1259
	if (!proc_bus_input_dir)
		return -ENOMEM;

1260 1261
	entry = proc_create("devices", 0, proc_bus_input_dir,
			    &input_devices_fileops);
1262 1263 1264
	if (!entry)
		goto fail1;

1265 1266
	entry = proc_create("handlers", 0, proc_bus_input_dir,
			    &input_handlers_fileops);
1267 1268 1269 1270 1271 1272
	if (!entry)
		goto fail2;

	return 0;

 fail2:	remove_proc_entry("devices", proc_bus_input_dir);
A
Alexey Dobriyan 已提交
1273
 fail1: remove_proc_entry("bus/input", NULL);
1274 1275 1276
	return -ENOMEM;
}

1277
static void input_proc_exit(void)
1278 1279 1280
{
	remove_proc_entry("devices", proc_bus_input_dir);
	remove_proc_entry("handlers", proc_bus_input_dir);
A
Alexey Dobriyan 已提交
1281
	remove_proc_entry("bus/input", NULL);
1282 1283 1284 1285 1286 1287 1288 1289
}

#else /* !CONFIG_PROC_FS */
static inline void input_wakeup_procfs_readers(void) { }
static inline int input_proc_init(void) { return 0; }
static inline void input_proc_exit(void) { }
#endif

1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300
#define INPUT_DEV_STRING_ATTR_SHOW(name)				\
static ssize_t input_dev_show_##name(struct device *dev,		\
				     struct device_attribute *attr,	\
				     char *buf)				\
{									\
	struct input_dev *input_dev = to_input_dev(dev);		\
									\
	return scnprintf(buf, PAGE_SIZE, "%s\n",			\
			 input_dev->name ? input_dev->name : "");	\
}									\
static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1301 1302 1303 1304 1305

INPUT_DEV_STRING_ATTR_SHOW(name);
INPUT_DEV_STRING_ATTR_SHOW(phys);
INPUT_DEV_STRING_ATTR_SHOW(uniq);

1306 1307 1308
static int input_print_modalias_bits(char *buf, int size,
				     char name, unsigned long *bm,
				     unsigned int min_bit, unsigned int max_bit)
1309
{
1310
	int len = 0, i;
1311

1312 1313
	len += snprintf(buf, max(size, 0), "%c", name);
	for (i = min_bit; i < max_bit; i++)
1314
		if (bm[BIT_WORD(i)] & BIT_MASK(i))
1315
			len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1316 1317 1318
	return len;
}

1319 1320
static int input_print_modalias(char *buf, int size, struct input_dev *id,
				int add_cr)
1321
{
1322
	int len;
1323

1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346
	len = snprintf(buf, max(size, 0),
		       "input:b%04Xv%04Xp%04Xe%04X-",
		       id->id.bustype, id->id.vendor,
		       id->id.product, id->id.version);

	len += input_print_modalias_bits(buf + len, size - len,
				'e', id->evbit, 0, EV_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				'r', id->relbit, 0, REL_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				'a', id->absbit, 0, ABS_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				'm', id->mscbit, 0, MSC_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				'l', id->ledbit, 0, LED_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				's', id->sndbit, 0, SND_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				'f', id->ffbit, 0, FF_MAX);
	len += input_print_modalias_bits(buf + len, size - len,
				'w', id->swbit, 0, SW_MAX);
1347 1348

	if (add_cr)
1349
		len += snprintf(buf + len, max(size - len, 0), "\n");
1350

1351 1352 1353
	return len;
}

1354 1355 1356
static ssize_t input_dev_show_modalias(struct device *dev,
				       struct device_attribute *attr,
				       char *buf)
1357 1358 1359 1360
{
	struct input_dev *id = to_input_dev(dev);
	ssize_t len;

1361 1362
	len = input_print_modalias(buf, PAGE_SIZE, id, 1);

1363
	return min_t(int, len, PAGE_SIZE);
1364
}
1365
static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1366

1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380
static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
			      int max, int add_cr);

static ssize_t input_dev_show_properties(struct device *dev,
					 struct device_attribute *attr,
					 char *buf)
{
	struct input_dev *input_dev = to_input_dev(dev);
	int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
				     INPUT_PROP_MAX, true);
	return min_t(int, len, PAGE_SIZE);
}
static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);

1381
static struct attribute *input_dev_attrs[] = {
1382 1383 1384 1385
	&dev_attr_name.attr,
	&dev_attr_phys.attr,
	&dev_attr_uniq.attr,
	&dev_attr_modalias.attr,
1386
	&dev_attr_properties.attr,
1387 1388 1389
	NULL
};

1390
static struct attribute_group input_dev_attr_group = {
1391
	.attrs	= input_dev_attrs,
1392 1393
};

1394 1395 1396 1397 1398 1399 1400 1401 1402
#define INPUT_DEV_ID_ATTR(name)						\
static ssize_t input_dev_show_id_##name(struct device *dev,		\
					struct device_attribute *attr,	\
					char *buf)			\
{									\
	struct input_dev *input_dev = to_input_dev(dev);		\
	return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name);	\
}									\
static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1403 1404 1405 1406 1407 1408 1409

INPUT_DEV_ID_ATTR(bustype);
INPUT_DEV_ID_ATTR(vendor);
INPUT_DEV_ID_ATTR(product);
INPUT_DEV_ID_ATTR(version);

static struct attribute *input_dev_id_attrs[] = {
1410 1411 1412 1413
	&dev_attr_bustype.attr,
	&dev_attr_vendor.attr,
	&dev_attr_product.attr,
	&dev_attr_version.attr,
1414 1415 1416 1417 1418 1419 1420 1421
	NULL
};

static struct attribute_group input_dev_id_attr_group = {
	.name	= "id",
	.attrs	= input_dev_id_attrs,
};

1422 1423 1424 1425 1426
static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
			      int max, int add_cr)
{
	int i;
	int len = 0;
1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437
	bool skip_empty = true;

	for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
		len += input_bits_to_string(buf + len, max(buf_size - len, 0),
					    bitmap[i], skip_empty);
		if (len) {
			skip_empty = false;
			if (i > 0)
				len += snprintf(buf + len, max(buf_size - len, 0), " ");
		}
	}
1438

1439 1440 1441 1442 1443
	/*
	 * If no output was produced print a single 0.
	 */
	if (len == 0)
		len = snprintf(buf, buf_size, "%d", 0);
1444 1445 1446 1447 1448 1449 1450

	if (add_cr)
		len += snprintf(buf + len, max(buf_size - len, 0), "\n");

	return len;
}

1451 1452 1453 1454 1455 1456 1457
#define INPUT_DEV_CAP_ATTR(ev, bm)					\
static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
				       struct device_attribute *attr,	\
				       char *buf)			\
{									\
	struct input_dev *input_dev = to_input_dev(dev);		\
	int len = input_print_bitmap(buf, PAGE_SIZE,			\
1458 1459
				     input_dev->bm##bit, ev##_MAX,	\
				     true);				\
1460 1461 1462
	return min_t(int, len, PAGE_SIZE);				\
}									\
static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474

INPUT_DEV_CAP_ATTR(EV, ev);
INPUT_DEV_CAP_ATTR(KEY, key);
INPUT_DEV_CAP_ATTR(REL, rel);
INPUT_DEV_CAP_ATTR(ABS, abs);
INPUT_DEV_CAP_ATTR(MSC, msc);
INPUT_DEV_CAP_ATTR(LED, led);
INPUT_DEV_CAP_ATTR(SND, snd);
INPUT_DEV_CAP_ATTR(FF, ff);
INPUT_DEV_CAP_ATTR(SW, sw);

static struct attribute *input_dev_caps_attrs[] = {
1475 1476 1477 1478 1479 1480 1481 1482 1483
	&dev_attr_ev.attr,
	&dev_attr_key.attr,
	&dev_attr_rel.attr,
	&dev_attr_abs.attr,
	&dev_attr_msc.attr,
	&dev_attr_led.attr,
	&dev_attr_snd.attr,
	&dev_attr_ff.attr,
	&dev_attr_sw.attr,
1484 1485 1486 1487 1488 1489 1490 1491
	NULL
};

static struct attribute_group input_dev_caps_attr_group = {
	.name	= "capabilities",
	.attrs	= input_dev_caps_attrs,
};

1492
static const struct attribute_group *input_dev_attr_groups[] = {
1493 1494 1495 1496 1497 1498
	&input_dev_attr_group,
	&input_dev_id_attr_group,
	&input_dev_caps_attr_group,
	NULL
};

1499
static void input_dev_release(struct device *device)
1500
{
1501
	struct input_dev *dev = to_input_dev(device);
1502

1503
	input_ff_destroy(dev);
H
Henrik Rydberg 已提交
1504
	input_mt_destroy_slots(dev);
1505
	kfree(dev->absinfo);
1506
	kfree(dev->vals);
1507
	kfree(dev);
1508

1509 1510 1511
	module_put(THIS_MODULE);
}

1512
/*
1513
 * Input uevent interface - loading event handlers based on
1514 1515
 * device bitfields.
 */
1516
static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1517
				   const char *name, unsigned long *bitmap, int max)
1518
{
1519
	int len;
1520

1521
	if (add_uevent_var(env, "%s", name))
1522 1523
		return -ENOMEM;

1524 1525
	len = input_print_bitmap(&env->buf[env->buflen - 1],
				 sizeof(env->buf) - env->buflen,
1526
				 bitmap, max, false);
1527
	if (len >= (sizeof(env->buf) - env->buflen))
1528 1529
		return -ENOMEM;

1530
	env->buflen += len;
1531 1532 1533
	return 0;
}

1534
static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1535 1536
					 struct input_dev *dev)
{
1537
	int len;
1538

1539
	if (add_uevent_var(env, "MODALIAS="))
1540 1541
		return -ENOMEM;

1542 1543 1544 1545
	len = input_print_modalias(&env->buf[env->buflen - 1],
				   sizeof(env->buf) - env->buflen,
				   dev, 0);
	if (len >= (sizeof(env->buf) - env->buflen))
1546 1547
		return -ENOMEM;

1548
	env->buflen += len;
1549 1550 1551
	return 0;
}

1552 1553
#define INPUT_ADD_HOTPLUG_VAR(fmt, val...)				\
	do {								\
1554
		int err = add_uevent_var(env, fmt, val);		\
1555 1556 1557 1558 1559 1560
		if (err)						\
			return err;					\
	} while (0)

#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max)				\
	do {								\
1561
		int err = input_add_uevent_bm_var(env, name, bm, max);	\
1562 1563 1564 1565
		if (err)						\
			return err;					\
	} while (0)

1566 1567
#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev)				\
	do {								\
1568
		int err = input_add_uevent_modalias_var(env, dev);	\
1569 1570 1571 1572
		if (err)						\
			return err;					\
	} while (0)

1573
static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1574
{
1575
	struct input_dev *dev = to_input_dev(device);
1576 1577 1578 1579 1580 1581 1582 1583

	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
				dev->id.bustype, dev->id.vendor,
				dev->id.product, dev->id.version);
	if (dev->name)
		INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
	if (dev->phys)
		INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1584
	if (dev->uniq)
1585 1586
		INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);

1587 1588
	INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);

1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606
	INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
	if (test_bit(EV_KEY, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
	if (test_bit(EV_REL, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
	if (test_bit(EV_ABS, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
	if (test_bit(EV_MSC, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
	if (test_bit(EV_LED, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
	if (test_bit(EV_SND, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
	if (test_bit(EV_FF, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
	if (test_bit(EV_SW, dev->evbit))
		INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);

1607
	INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1608 1609 1610 1611

	return 0;
}

D
Dmitry Torokhov 已提交
1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629
#define INPUT_DO_TOGGLE(dev, type, bits, on)				\
	do {								\
		int i;							\
		bool active;						\
									\
		if (!test_bit(EV_##type, dev->evbit))			\
			break;						\
									\
		for (i = 0; i < type##_MAX; i++) {			\
			if (!test_bit(i, dev->bits##bit))		\
				continue;				\
									\
			active = test_bit(i, dev->bits);		\
			if (!active && !on)				\
				continue;				\
									\
			dev->event(dev, EV_##type, i, on ? active : 0);	\
		}							\
1630 1631
	} while (0)

1632
static void input_dev_toggle(struct input_dev *dev, bool activate)
1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645
{
	if (!dev->event)
		return;

	INPUT_DO_TOGGLE(dev, LED, led, activate);
	INPUT_DO_TOGGLE(dev, SND, snd, activate);

	if (activate && test_bit(EV_REP, dev->evbit)) {
		dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
		dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
	}
}

1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674
/**
 * input_reset_device() - reset/restore the state of input device
 * @dev: input device whose state needs to be reset
 *
 * This function tries to reset the state of an opened input device and
 * bring internal state and state if the hardware in sync with each other.
 * We mark all keys as released, restore LED state, repeat rate, etc.
 */
void input_reset_device(struct input_dev *dev)
{
	mutex_lock(&dev->mutex);

	if (dev->users) {
		input_dev_toggle(dev, true);

		/*
		 * Keys that have been pressed at suspend time are unlikely
		 * to be still pressed when we resume.
		 */
		spin_lock_irq(&dev->event_lock);
		input_dev_release_keys(dev);
		spin_unlock_irq(&dev->event_lock);
	}

	mutex_unlock(&dev->mutex);
}
EXPORT_SYMBOL(input_reset_device);

#ifdef CONFIG_PM
1675 1676 1677 1678 1679
static int input_dev_suspend(struct device *dev)
{
	struct input_dev *input_dev = to_input_dev(dev);

	mutex_lock(&input_dev->mutex);
1680 1681 1682 1683

	if (input_dev->users)
		input_dev_toggle(input_dev, false);

1684 1685 1686 1687 1688 1689 1690 1691 1692
	mutex_unlock(&input_dev->mutex);

	return 0;
}

static int input_dev_resume(struct device *dev)
{
	struct input_dev *input_dev = to_input_dev(dev);

1693
	input_reset_device(input_dev);
1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705

	return 0;
}

static const struct dev_pm_ops input_dev_pm_ops = {
	.suspend	= input_dev_suspend,
	.resume		= input_dev_resume,
	.poweroff	= input_dev_suspend,
	.restore	= input_dev_resume,
};
#endif /* CONFIG_PM */

1706 1707 1708 1709
static struct device_type input_dev_type = {
	.groups		= input_dev_attr_groups,
	.release	= input_dev_release,
	.uevent		= input_dev_uevent,
1710 1711 1712
#ifdef CONFIG_PM
	.pm		= &input_dev_pm_ops,
#endif
1713 1714
};

1715
static char *input_devnode(struct device *dev, umode_t *mode)
1716 1717 1718 1719
{
	return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
}

1720
struct class input_class = {
1721
	.name		= "input",
1722
	.devnode	= input_devnode,
1723
};
D
Dmitry Torokhov 已提交
1724
EXPORT_SYMBOL_GPL(input_class);
1725

1726 1727 1728
/**
 * input_allocate_device - allocate memory for new input device
 *
1729
 * Returns prepared struct input_dev or %NULL.
1730 1731 1732 1733 1734
 *
 * NOTE: Use input_free_device() to free devices that have not been
 * registered; input_unregister_device() should be used for already
 * registered devices.
 */
1735 1736
struct input_dev *input_allocate_device(void)
{
1737
	static atomic_t input_no = ATOMIC_INIT(0);
1738 1739 1740 1741
	struct input_dev *dev;

	dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
	if (dev) {
1742 1743 1744
		dev->dev.type = &input_dev_type;
		dev->dev.class = &input_class;
		device_initialize(&dev->dev);
1745
		mutex_init(&dev->mutex);
1746
		spin_lock_init(&dev->event_lock);
1747
		init_timer(&dev->timer);
1748 1749
		INIT_LIST_HEAD(&dev->h_list);
		INIT_LIST_HEAD(&dev->node);
1750

1751 1752 1753
		dev_set_name(&dev->dev, "input%ld",
			     (unsigned long) atomic_inc_return(&input_no) - 1);

1754
		__module_get(THIS_MODULE);
1755 1756 1757 1758
	}

	return dev;
}
D
Dmitry Torokhov 已提交
1759
EXPORT_SYMBOL(input_allocate_device);
1760

1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792
struct input_devres {
	struct input_dev *input;
};

static int devm_input_device_match(struct device *dev, void *res, void *data)
{
	struct input_devres *devres = res;

	return devres->input == data;
}

static void devm_input_device_release(struct device *dev, void *res)
{
	struct input_devres *devres = res;
	struct input_dev *input = devres->input;

	dev_dbg(dev, "%s: dropping reference to %s\n",
		__func__, dev_name(&input->dev));
	input_put_device(input);
}

/**
 * devm_input_allocate_device - allocate managed input device
 * @dev: device owning the input device being created
 *
 * Returns prepared struct input_dev or %NULL.
 *
 * Managed input devices do not need to be explicitly unregistered or
 * freed as it will be done automatically when owner device unbinds from
 * its driver (or binding fails). Once managed input device is allocated,
 * it is ready to be set up and registered in the same fashion as regular
 * input device. There are no special devm_input_device_[un]register()
1793 1794 1795
 * variants, regular ones work with both managed and unmanaged devices,
 * should you need them. In most cases however, managed input device need
 * not be explicitly unregistered or freed.
1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825
 *
 * NOTE: the owner device is set up as parent of input device and users
 * should not override it.
 */
struct input_dev *devm_input_allocate_device(struct device *dev)
{
	struct input_dev *input;
	struct input_devres *devres;

	devres = devres_alloc(devm_input_device_release,
			      sizeof(struct input_devres), GFP_KERNEL);
	if (!devres)
		return NULL;

	input = input_allocate_device();
	if (!input) {
		devres_free(devres);
		return NULL;
	}

	input->dev.parent = dev;
	input->devres_managed = true;

	devres->input = input;
	devres_add(dev, devres);

	return input;
}
EXPORT_SYMBOL(devm_input_allocate_device);

1826 1827 1828 1829 1830 1831 1832
/**
 * input_free_device - free memory occupied by input_dev structure
 * @dev: input device to free
 *
 * This function should only be used if input_register_device()
 * was not called yet or if it failed. Once device was registered
 * use input_unregister_device() and memory will be freed once last
1833
 * reference to the device is dropped.
1834 1835 1836 1837 1838 1839
 *
 * Device should be allocated by input_allocate_device().
 *
 * NOTE: If there are references to the input device then memory
 * will not be freed until last reference is dropped.
 */
1840 1841
void input_free_device(struct input_dev *dev)
{
1842 1843 1844 1845 1846 1847
	if (dev) {
		if (dev->devres_managed)
			WARN_ON(devres_destroy(dev->dev.parent,
						devm_input_device_release,
						devm_input_device_match,
						dev));
1848
		input_put_device(dev);
1849
	}
1850
}
D
Dmitry Torokhov 已提交
1851
EXPORT_SYMBOL(input_free_device);
1852

1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873
/**
 * input_set_capability - mark device as capable of a certain event
 * @dev: device that is capable of emitting or accepting event
 * @type: type of the event (EV_KEY, EV_REL, etc...)
 * @code: event code
 *
 * In addition to setting up corresponding bit in appropriate capability
 * bitmap the function also adjusts dev->evbit.
 */
void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
{
	switch (type) {
	case EV_KEY:
		__set_bit(code, dev->keybit);
		break;

	case EV_REL:
		__set_bit(code, dev->relbit);
		break;

	case EV_ABS:
1874 1875 1876 1877
		input_alloc_absinfo(dev);
		if (!dev->absinfo)
			return;

1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900
		__set_bit(code, dev->absbit);
		break;

	case EV_MSC:
		__set_bit(code, dev->mscbit);
		break;

	case EV_SW:
		__set_bit(code, dev->swbit);
		break;

	case EV_LED:
		__set_bit(code, dev->ledbit);
		break;

	case EV_SND:
		__set_bit(code, dev->sndbit);
		break;

	case EV_FF:
		__set_bit(code, dev->ffbit);
		break;

1901 1902 1903 1904
	case EV_PWR:
		/* do nothing */
		break;

1905
	default:
J
Joe Perches 已提交
1906 1907
		pr_err("input_set_capability: unknown type %u (code %u)\n",
		       type, code);
1908 1909 1910 1911 1912 1913 1914 1915
		dump_stack();
		return;
	}

	__set_bit(type, dev->evbit);
}
EXPORT_SYMBOL(input_set_capability);

1916 1917 1918 1919 1920 1921
static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
{
	int mt_slots;
	int i;
	unsigned int events;

H
Henrik Rydberg 已提交
1922 1923
	if (dev->mt) {
		mt_slots = dev->mt->num_slots;
1924 1925 1926
	} else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
		mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
			   dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1927
		mt_slots = clamp(mt_slots, 2, 32);
1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948
	} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
		mt_slots = 2;
	} else {
		mt_slots = 0;
	}

	events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */

	for (i = 0; i < ABS_CNT; i++) {
		if (test_bit(i, dev->absbit)) {
			if (input_is_mt_axis(i))
				events += mt_slots;
			else
				events++;
		}
	}

	for (i = 0; i < REL_CNT; i++)
		if (test_bit(i, dev->relbit))
			events++;

1949 1950 1951
	/* Make room for KEY and MSC events */
	events += 7;

1952 1953 1954
	return events;
}

1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973
#define INPUT_CLEANSE_BITMASK(dev, type, bits)				\
	do {								\
		if (!test_bit(EV_##type, dev->evbit))			\
			memset(dev->bits##bit, 0,			\
				sizeof(dev->bits##bit));		\
	} while (0)

static void input_cleanse_bitmasks(struct input_dev *dev)
{
	INPUT_CLEANSE_BITMASK(dev, KEY, key);
	INPUT_CLEANSE_BITMASK(dev, REL, rel);
	INPUT_CLEANSE_BITMASK(dev, ABS, abs);
	INPUT_CLEANSE_BITMASK(dev, MSC, msc);
	INPUT_CLEANSE_BITMASK(dev, LED, led);
	INPUT_CLEANSE_BITMASK(dev, SND, snd);
	INPUT_CLEANSE_BITMASK(dev, FF, ff);
	INPUT_CLEANSE_BITMASK(dev, SW, sw);
}

1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
static void __input_unregister_device(struct input_dev *dev)
{
	struct input_handle *handle, *next;

	input_disconnect_device(dev);

	mutex_lock(&input_mutex);

	list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
		handle->handler->disconnect(handle);
	WARN_ON(!list_empty(&dev->h_list));

	del_timer_sync(&dev->timer);
	list_del_init(&dev->node);

	input_wakeup_procfs_readers();

	mutex_unlock(&input_mutex);

	device_del(&dev->dev);
}

static void devm_input_device_unregister(struct device *dev, void *res)
{
	struct input_devres *devres = res;
	struct input_dev *input = devres->input;

	dev_dbg(dev, "%s: unregistering device %s\n",
		__func__, dev_name(&input->dev));
	__input_unregister_device(input);
}

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
/**
 * input_register_device - register device with input core
 * @dev: device to be registered
 *
 * This function registers device with input core. The device must be
 * allocated with input_allocate_device() and all it's capabilities
 * set up before registering.
 * If function fails the device must be freed with input_free_device().
 * Once device has been successfully registered it can be unregistered
 * with input_unregister_device(); input_free_device() should not be
 * called in this case.
2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027
 *
 * Note that this function is also used to register managed input devices
 * (ones allocated with devm_input_allocate_device()). Such managed input
 * devices need not be explicitly unregistered or freed, their tear down
 * is controlled by the devres infrastructure. It is also worth noting
 * that tear down of managed input devices is internally a 2-step process:
 * registered managed input device is first unregistered, but stays in
 * memory and can still handle input_event() calls (although events will
 * not be delivered anywhere). The freeing of managed input device will
 * happen later, when devres stack is unwound to the point where device
 * allocation was made.
2028
 */
2029
int input_register_device(struct input_dev *dev)
L
Linus Torvalds 已提交
2030
{
2031
	struct input_devres *devres = NULL;
L
Linus Torvalds 已提交
2032
	struct input_handler *handler;
2033
	unsigned int packet_size;
2034 2035
	const char *path;
	int error;
L
Linus Torvalds 已提交
2036

2037 2038 2039 2040 2041 2042 2043 2044 2045
	if (dev->devres_managed) {
		devres = devres_alloc(devm_input_device_unregister,
				      sizeof(struct input_devres), GFP_KERNEL);
		if (!devres)
			return -ENOMEM;

		devres->input = dev;
	}

2046
	/* Every input device generates EV_SYN/SYN_REPORT events. */
2047
	__set_bit(EV_SYN, dev->evbit);
2048

2049 2050 2051
	/* KEY_RESERVED is not supposed to be transmitted to userspace. */
	__clear_bit(KEY_RESERVED, dev->keybit);

2052 2053 2054
	/* Make sure that bitmasks not mentioned in dev->evbit are clean. */
	input_cleanse_bitmasks(dev);

2055 2056 2057
	packet_size = input_estimate_events_per_packet(dev);
	if (dev->hint_events_per_packet < packet_size)
		dev->hint_events_per_packet = packet_size;
2058

K
Kang Hu 已提交
2059
	dev->max_vals = dev->hint_events_per_packet + 2;
2060
	dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
2061 2062 2063 2064
	if (!dev->vals) {
		error = -ENOMEM;
		goto err_devres_free;
	}
2065

L
Linus Torvalds 已提交
2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076
	/*
	 * If delay and period are pre-set by the driver, then autorepeating
	 * is handled by the driver itself and we don't do it in input.c.
	 */
	if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
		dev->timer.data = (long) dev;
		dev->timer.function = input_repeat_key;
		dev->rep[REP_DELAY] = 250;
		dev->rep[REP_PERIOD] = 33;
	}

2077 2078
	if (!dev->getkeycode)
		dev->getkeycode = input_default_getkeycode;
2079

2080 2081
	if (!dev->setkeycode)
		dev->setkeycode = input_default_setkeycode;
2082

2083
	error = device_add(&dev->dev);
2084
	if (error)
2085
		goto err_free_vals;
2086

2087
	path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
J
Joe Perches 已提交
2088 2089 2090
	pr_info("%s as %s\n",
		dev->name ? dev->name : "Unspecified device",
		path ? path : "N/A");
2091
	kfree(path);
2092

2093
	error = mutex_lock_interruptible(&input_mutex);
2094 2095
	if (error)
		goto err_device_del;
2096 2097 2098

	list_add_tail(&dev->node, &input_dev_list);

L
Linus Torvalds 已提交
2099
	list_for_each_entry(handler, &input_handler_list, node)
2100
		input_attach_handler(dev, handler);
L
Linus Torvalds 已提交
2101

2102
	input_wakeup_procfs_readers();
2103

2104 2105
	mutex_unlock(&input_mutex);

2106 2107 2108 2109 2110
	if (dev->devres_managed) {
		dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
			__func__, dev_name(&dev->dev));
		devres_add(dev->dev.parent, devres);
	}
2111
	return 0;
2112 2113 2114 2115 2116 2117 2118 2119 2120

err_device_del:
	device_del(&dev->dev);
err_free_vals:
	kfree(dev->vals);
	dev->vals = NULL;
err_devres_free:
	devres_free(devres);
	return error;
L
Linus Torvalds 已提交
2121
}
D
Dmitry Torokhov 已提交
2122
EXPORT_SYMBOL(input_register_device);
L
Linus Torvalds 已提交
2123

2124 2125 2126 2127 2128 2129 2130
/**
 * input_unregister_device - unregister previously registered device
 * @dev: device to be unregistered
 *
 * This function unregisters an input device. Once device is unregistered
 * the caller should not try to access it as it may get freed at any moment.
 */
L
Linus Torvalds 已提交
2131 2132
void input_unregister_device(struct input_dev *dev)
{
2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146
	if (dev->devres_managed) {
		WARN_ON(devres_destroy(dev->dev.parent,
					devm_input_device_unregister,
					devm_input_device_match,
					dev));
		__input_unregister_device(dev);
		/*
		 * We do not do input_put_device() here because it will be done
		 * when 2nd devres fires up.
		 */
	} else {
		__input_unregister_device(dev);
		input_put_device(dev);
	}
L
Linus Torvalds 已提交
2147
}
D
Dmitry Torokhov 已提交
2148
EXPORT_SYMBOL(input_unregister_device);
L
Linus Torvalds 已提交
2149

2150 2151 2152 2153 2154 2155 2156 2157
/**
 * input_register_handler - register a new input handler
 * @handler: handler to be registered
 *
 * This function registers a new input handler (interface) for input
 * devices in the system and attaches it to all input devices that
 * are compatible with the handler.
 */
2158
int input_register_handler(struct input_handler *handler)
L
Linus Torvalds 已提交
2159 2160
{
	struct input_dev *dev;
2161
	int error;
2162

2163 2164 2165
	error = mutex_lock_interruptible(&input_mutex);
	if (error)
		return error;
L
Linus Torvalds 已提交
2166 2167 2168 2169 2170 2171

	INIT_LIST_HEAD(&handler->h_list);

	list_add_tail(&handler->node, &input_handler_list);

	list_for_each_entry(dev, &input_dev_list, node)
2172
		input_attach_handler(dev, handler);
L
Linus Torvalds 已提交
2173

2174
	input_wakeup_procfs_readers();
2175 2176

	mutex_unlock(&input_mutex);
2177
	return 0;
L
Linus Torvalds 已提交
2178
}
D
Dmitry Torokhov 已提交
2179
EXPORT_SYMBOL(input_register_handler);
L
Linus Torvalds 已提交
2180

2181 2182 2183 2184 2185 2186 2187
/**
 * input_unregister_handler - unregisters an input handler
 * @handler: handler to be unregistered
 *
 * This function disconnects a handler from its input devices and
 * removes it from lists of known handlers.
 */
L
Linus Torvalds 已提交
2188 2189
void input_unregister_handler(struct input_handler *handler)
{
2190
	struct input_handle *handle, *next;
L
Linus Torvalds 已提交
2191

2192 2193
	mutex_lock(&input_mutex);

2194
	list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
L
Linus Torvalds 已提交
2195
		handler->disconnect(handle);
2196
	WARN_ON(!list_empty(&handler->h_list));
L
Linus Torvalds 已提交
2197 2198 2199

	list_del_init(&handler->node);

2200
	input_wakeup_procfs_readers();
2201 2202

	mutex_unlock(&input_mutex);
L
Linus Torvalds 已提交
2203
}
D
Dmitry Torokhov 已提交
2204
EXPORT_SYMBOL(input_unregister_handler);
L
Linus Torvalds 已提交
2205

2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237
/**
 * input_handler_for_each_handle - handle iterator
 * @handler: input handler to iterate
 * @data: data for the callback
 * @fn: function to be called for each handle
 *
 * Iterate over @bus's list of devices, and call @fn for each, passing
 * it @data and stop when @fn returns a non-zero value. The function is
 * using RCU to traverse the list and therefore may be usind in atonic
 * contexts. The @fn callback is invoked from RCU critical section and
 * thus must not sleep.
 */
int input_handler_for_each_handle(struct input_handler *handler, void *data,
				  int (*fn)(struct input_handle *, void *))
{
	struct input_handle *handle;
	int retval = 0;

	rcu_read_lock();

	list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
		retval = fn(handle, data);
		if (retval)
			break;
	}

	rcu_read_unlock();

	return retval;
}
EXPORT_SYMBOL(input_handler_for_each_handle);

2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248
/**
 * input_register_handle - register a new input handle
 * @handle: handle to register
 *
 * This function puts a new input handle onto device's
 * and handler's lists so that events can flow through
 * it once it is opened using input_open_device().
 *
 * This function is supposed to be called from handler's
 * connect() method.
 */
2249 2250 2251
int input_register_handle(struct input_handle *handle)
{
	struct input_handler *handler = handle->handler;
2252 2253 2254 2255 2256 2257 2258 2259 2260 2261
	struct input_dev *dev = handle->dev;
	int error;

	/*
	 * We take dev->mutex here to prevent race with
	 * input_release_device().
	 */
	error = mutex_lock_interruptible(&dev->mutex);
	if (error)
		return error;
D
Dmitry Torokhov 已提交
2262 2263 2264 2265 2266 2267 2268 2269 2270 2271

	/*
	 * Filters go to the head of the list, normal handlers
	 * to the tail.
	 */
	if (handler->filter)
		list_add_rcu(&handle->d_node, &dev->h_list);
	else
		list_add_tail_rcu(&handle->d_node, &dev->h_list);

2272
	mutex_unlock(&dev->mutex);
2273

2274 2275 2276 2277 2278 2279
	/*
	 * Since we are supposed to be called from ->connect()
	 * which is mutually exclusive with ->disconnect()
	 * we can't be racing with input_unregister_handle()
	 * and so separate lock is not needed here.
	 */
2280
	list_add_tail_rcu(&handle->h_node, &handler->h_list);
2281 2282 2283 2284 2285 2286 2287 2288

	if (handler->start)
		handler->start(handle);

	return 0;
}
EXPORT_SYMBOL(input_register_handle);

2289 2290 2291 2292 2293 2294 2295 2296 2297 2298
/**
 * input_unregister_handle - unregister an input handle
 * @handle: handle to unregister
 *
 * This function removes input handle from device's
 * and handler's lists.
 *
 * This function is supposed to be called from handler's
 * disconnect() method.
 */
2299 2300
void input_unregister_handle(struct input_handle *handle)
{
2301 2302
	struct input_dev *dev = handle->dev;

2303
	list_del_rcu(&handle->h_node);
2304 2305 2306 2307 2308 2309 2310

	/*
	 * Take dev->mutex to prevent race with input_release_device().
	 */
	mutex_lock(&dev->mutex);
	list_del_rcu(&handle->d_node);
	mutex_unlock(&dev->mutex);
2311

D
Dmitry Torokhov 已提交
2312
	synchronize_rcu();
2313 2314 2315
}
EXPORT_SYMBOL(input_unregister_handle);

2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328
/**
 * input_get_new_minor - allocates a new input minor number
 * @legacy_base: beginning or the legacy range to be searched
 * @legacy_num: size of legacy range
 * @allow_dynamic: whether we can also take ID from the dynamic range
 *
 * This function allocates a new device minor for from input major namespace.
 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
 * parameters and whether ID can be allocated from dynamic range if there are
 * no free IDs in legacy range.
 */
int input_get_new_minor(int legacy_base, unsigned int legacy_num,
			bool allow_dynamic)
L
Linus Torvalds 已提交
2329 2330
{
	/*
2331 2332 2333
	 * This function should be called from input handler's ->connect()
	 * methods, which are serialized with input_mutex, so no additional
	 * locking is needed here.
L
Linus Torvalds 已提交
2334
	 */
2335 2336 2337 2338 2339 2340 2341
	if (legacy_base >= 0) {
		int minor = ida_simple_get(&input_ida,
					   legacy_base,
					   legacy_base + legacy_num,
					   GFP_KERNEL);
		if (minor >= 0 || !allow_dynamic)
			return minor;
L
Linus Torvalds 已提交
2342
	}
2343

2344 2345 2346
	return ida_simple_get(&input_ida,
			      INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
			      GFP_KERNEL);
L
Linus Torvalds 已提交
2347
}
2348
EXPORT_SYMBOL(input_get_new_minor);
L
Linus Torvalds 已提交
2349

2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361
/**
 * input_free_minor - release previously allocated minor
 * @minor: minor to be released
 *
 * This function releases previously allocated input minor so that it can be
 * reused later.
 */
void input_free_minor(unsigned int minor)
{
	ida_simple_remove(&input_ida, minor);
}
EXPORT_SYMBOL(input_free_minor);
L
Linus Torvalds 已提交
2362

2363
static int __init input_init(void)
L
Linus Torvalds 已提交
2364
{
2365
	int err;
L
Linus Torvalds 已提交
2366

2367
	err = class_register(&input_class);
2368
	if (err) {
J
Joe Perches 已提交
2369
		pr_err("unable to register input_dev class\n");
2370 2371 2372
		return err;
	}

2373 2374
	err = input_proc_init();
	if (err)
2375
		goto fail1;
L
Linus Torvalds 已提交
2376

2377 2378
	err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
				     INPUT_MAX_CHAR_DEVICES, "input");
2379
	if (err) {
J
Joe Perches 已提交
2380
		pr_err("unable to register char major %d", INPUT_MAJOR);
2381
		goto fail2;
L
Linus Torvalds 已提交
2382
	}
2383

L
Linus Torvalds 已提交
2384 2385
	return 0;

2386
 fail2:	input_proc_exit();
2387
 fail1:	class_unregister(&input_class);
2388
	return err;
L
Linus Torvalds 已提交
2389 2390 2391 2392
}

static void __exit input_exit(void)
{
2393
	input_proc_exit();
2394 2395
	unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
				 INPUT_MAX_CHAR_DEVICES);
2396
	class_unregister(&input_class);
L
Linus Torvalds 已提交
2397 2398 2399 2400
}

subsys_initcall(input_init);
module_exit(input_exit);