Release 4.11 drivers/input/joydev.c

/*
 * Joystick device driver for the input driver suite.
 *
 * Copyright (c) 1999-2002 Vojtech Pavlik
 * Copyright (c) 1999 Colin Van Dyke
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <asm/io.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/joystick.h>
#include <linux/input.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/cdev.h>

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Joystick device interfaces");
MODULE_SUPPORTED_DEVICE("input/js");
MODULE_LICENSE("GPL");


#define JOYDEV_MINOR_BASE	0

#define JOYDEV_MINORS		16

#define JOYDEV_BUFFER_SIZE	64


struct joydev {
	
int open;
	
struct input_handle handle;
	
wait_queue_head_t wait;
	
struct list_head client_list;
	
spinlock_t client_lock; /* protects client_list */
	
struct mutex mutex;
	
struct device dev;
	
struct cdev cdev;
	
bool exist;

	
struct js_corr corr[ABS_CNT];
	
struct JS_DATA_SAVE_TYPE glue;
	
int nabs;
	
int nkey;
	
__u16 keymap[KEY_MAX - BTN_MISC + 1];
	
__u16 keypam[KEY_MAX - BTN_MISC + 1];
	
__u8 absmap[ABS_CNT];
	
__u8 abspam[ABS_CNT];
	
__s16 abs[ABS_CNT];
};


struct joydev_client {
	
struct js_event buffer[JOYDEV_BUFFER_SIZE];
	
int head;
	
int tail;
	
int startup;
	
spinlock_t buffer_lock; /* protects access to buffer, head and tail */
	
struct fasync_struct *fasync;
	
struct joydev *joydev;
	
struct list_head node;
};



static int joydev_correct(int value, struct js_corr *corr)
{
	switch (corr->type) {

	case JS_CORR_NONE:
		break;

	case JS_CORR_BROKEN:
		value = value > corr->coef[0] ? (value < corr->coef[1] ? 0 :
			((corr->coef[3] * (value - corr->coef[1])) >> 14)) :
			((corr->coef[2] * (value - corr->coef[0])) >> 14);
		break;

	default:
		return 0;
	}

	return clamp(value, -32767, 32767);
}

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Linus Torvalds (pre-git)
111
94.87%
2
50.00%
Dmitry Torokhov
6
5.13%
2
50.00%
Total
117
100.00%
4
100.00%



static void joydev_pass_event(struct joydev_client *client,
			      struct js_event *event)
{
	struct joydev *joydev = client->joydev;

	/*
         * IRQs already disabled, just acquire the lock
         */
	spin_lock(&client->buffer_lock);

	client->buffer[client->head] = *event;

	if (client->startup == joydev->nabs + joydev->nkey) {
		client->head++;
		client->head &= JOYDEV_BUFFER_SIZE - 1;
		if (client->tail == client->head)
			client->startup = 0;
	}

	spin_unlock(&client->buffer_lock);

	kill_fasync(&client->fasync, SIGIO, POLL_IN);
}

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Dmitry Torokhov
111
100.00%
1
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111
100.00%
1
100.00%



static void joydev_event(struct input_handle *handle,
			 unsigned int type, unsigned int code, int value)
{
	struct joydev *joydev = handle->private;
	struct joydev_client *client;
	struct js_event event;

	switch (type) {

	case EV_KEY:
		if (code < BTN_MISC || value == 2)
			return;
		event.type = JS_EVENT_BUTTON;
		event.number = joydev->keymap[code - BTN_MISC];
		event.value = value;
		break;

	case EV_ABS:
		event.type = JS_EVENT_AXIS;
		event.number = joydev->absmap[code];
		event.value = joydev_correct(value,
					&joydev->corr[event.number]);
		if (event.value == joydev->abs[event.number])
			return;
		joydev->abs[event.number] = event.value;
		break;

	default:
		return;
	}

	event.time = jiffies_to_msecs(jiffies);

	rcu_read_lock();
	list_for_each_entry_rcu(client, &joydev->client_list, node)
		joydev_pass_event(client, &event);
	rcu_read_unlock();

	wake_up_interruptible(&joydev->wait);
}

Contributors
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Linus Torvalds (pre-git)
172
87.76%
4
40.00%
Dmitry Torokhov
16
8.16%
3
30.00%
Vojtech Pavlik
7
3.57%
2
20.00%
Tobias Klauser
1
0.51%
1
10.00%
Total
196
100.00%
10
100.00%



static int joydev_fasync(int fd, struct file *file, int on)
{
	struct joydev_client *client = file->private_data;

	return fasync_helper(fd, file, on, &client->fasync);
}

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Linus Torvalds (pre-git)
37
90.24%
1
33.33%
Dmitry Torokhov
3
7.32%
1
33.33%
Jonathan Corbet
1
2.44%
1
33.33%
Total
41
100.00%
3
100.00%



static void joydev_free(struct device *dev)
{
	struct joydev *joydev = container_of(dev, struct joydev, dev);

	input_put_device(joydev->handle.dev);
	kfree(joydev);
}

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Dmitry Torokhov
26
65.00%
2
66.67%
Christoph Hellwig
14
35.00%
1
33.33%
Total
40
100.00%
3
100.00%



static void joydev_attach_client(struct joydev *joydev,
				 struct joydev_client *client)
{
	spin_lock(&joydev->client_lock);
	list_add_tail_rcu(&client->node, &joydev->client_list);
	spin_unlock(&joydev->client_lock);
}

Contributors
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Dmitry Torokhov
28
62.22%
2
50.00%
Linus Torvalds (pre-git)
14
31.11%
1
25.00%
Vojtech Pavlik
3
6.67%
1
25.00%
Total
45
100.00%
4
100.00%



static void joydev_detach_client(struct joydev *joydev,
				 struct joydev_client *client)
{
	spin_lock(&joydev->client_lock);
	list_del_rcu(&client->node);
	spin_unlock(&joydev->client_lock);
	synchronize_rcu();
}

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Dmitry Torokhov
31
72.09%
3
50.00%
Linus Torvalds (pre-git)
12
27.91%
3
50.00%
Total
43
100.00%
6
100.00%



static void joydev_refresh_state(struct joydev *joydev)
{
	struct input_dev *dev = joydev->handle.dev;
	int i, val;

	for (i = 0; i < joydev->nabs; i++) {
		val = input_abs_get_val(dev, joydev->abspam[i]);
		joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
	}
}

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Raphaël Assénat
78
100.00%
1
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78
100.00%
1
100.00%



static int joydev_open_device(struct joydev *joydev)
{
	int retval;

	retval = mutex_lock_interruptible(&joydev->mutex);
	if (retval)
		return retval;

	if (!joydev->exist)
		retval = -ENODEV;
	else if (!joydev->open++) {
		retval = input_open_device(&joydev->handle);
		if (retval)
			joydev->open--;
		else
			joydev_refresh_state(joydev);
	}

	mutex_unlock(&joydev->mutex);
	return retval;
}

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Dmitry Torokhov
58
64.44%
3
50.00%
Linus Torvalds (pre-git)
15
16.67%
1
16.67%
Oliver Neukum
11
12.22%
1
16.67%
Raphaël Assénat
6
6.67%
1
16.67%
Total
90
100.00%
6
100.00%



static void joydev_close_device(struct joydev *joydev)
{
	mutex_lock(&joydev->mutex);

	if (joydev->exist && !--joydev->open)
		input_close_device(&joydev->handle);

	mutex_unlock(&joydev->mutex);
}

Contributors
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Dmitry Torokhov
27
57.45%
3
42.86%
Linus Torvalds (pre-git)
17
36.17%
3
42.86%
Vojtech Pavlik
3
6.38%
1
14.29%
Total
47
100.00%
7
100.00%

/*
 * Wake up users waiting for IO so they can disconnect from
 * dead device.
 */


static void joydev_hangup(struct joydev *joydev)
{
	struct joydev_client *client;

	spin_lock(&joydev->client_lock);
	list_for_each_entry(client, &joydev->client_list, node)
		kill_fasync(&client->fasync, SIGIO, POLL_HUP);
	spin_unlock(&joydev->client_lock);

	wake_up_interruptible(&joydev->wait);
}

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Dmitry Torokhov
59
98.33%
4
80.00%
Linus Torvalds (pre-git)
1
1.67%
1
20.00%
Total
60
100.00%
5
100.00%



static int joydev_release(struct inode *inode, struct file *file)
{
	struct joydev_client *client = file->private_data;
	struct joydev *joydev = client->joydev;

	joydev_detach_client(joydev, client);
	kfree(client);

	joydev_close_device(joydev);

	return 0;
}

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Dmitry Torokhov
48
88.89%
1
50.00%
Linus Torvalds (pre-git)
6
11.11%
1
50.00%
Total
54
100.00%
2
100.00%



static int joydev_open(struct inode *inode, struct file *file)
{
	struct joydev *joydev =
			container_of(inode->i_cdev, struct joydev, cdev);
	struct joydev_client *client;
	int error;

	client = kzalloc(sizeof(struct joydev_client), GFP_KERNEL);
	if (!client)
		return -ENOMEM;

	spin_lock_init(&client->buffer_lock);
	client->joydev = joydev;
	joydev_attach_client(joydev, client);

	error = joydev_open_device(joydev);
	if (error)
		goto err_free_client;

	file->private_data = client;
	nonseekable_open(inode, file);

	return 0;

 err_free_client:
	joydev_detach_client(joydev, client);
	kfree(client);
	return error;
}

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Dmitry Torokhov
129
98.47%
3
75.00%
Linus Torvalds (pre-git)
2
1.53%
1
25.00%
Total
131
100.00%
4
100.00%



static int joydev_generate_startup_event(struct joydev_client *client,
					 struct input_dev *input,
					 struct js_event *event)
{
	struct joydev *joydev = client->joydev;
	int have_event;

	spin_lock_irq(&client->buffer_lock);

	have_event = client->startup < joydev->nabs + joydev->nkey;

	if (have_event) {

		event->time = jiffies_to_msecs(jiffies);
		if (client->startup < joydev->nkey) {
			event->type = JS_EVENT_BUTTON | JS_EVENT_INIT;
			event->number = client->startup;
			event->value = !!test_bit(joydev->keypam[event->number],
						  input->key);
		} else {
			event->type = JS_EVENT_AXIS | JS_EVENT_INIT;
			event->number = client->startup - joydev->nkey;
			event->value = joydev->abs[event->number];
		}
		client->startup++;
	}

	spin_unlock_irq(&client->buffer_lock);

	return have_event;
}

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Dmitry Torokhov
166
96.51%
1
50.00%
Linus Torvalds (pre-git)
6
3.49%
1
50.00%
Total
172
100.00%
2
100.00%



static int joydev_fetch_next_event(struct joydev_client *client,
				   struct js_event *event)
{
	int have_event;

	spin_lock_irq(&client->buffer_lock);

	have_event = client->head != client->tail;
	if (have_event) {
		*event = client->buffer[client->tail++];
		client->tail &= JOYDEV_BUFFER_SIZE - 1;
	}

	spin_unlock_irq(&client->buffer_lock);

	return have_event;
}

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Dmitry Torokhov
72
96.00%
1
50.00%
Linus Torvalds (pre-git)
3
4.00%
1
50.00%
Total
75
100.00%
2
100.00%

/*
 * Old joystick interface
 */


static ssize_t joydev_0x_read(struct joydev_client *client,
			      struct input_dev *input,
			      char __user *buf)
{
	struct joydev *joydev = client->joydev;
	struct JS_DATA_TYPE data;
	int i;

	spin_lock_irq(&input->event_lock);

	/*
         * Get device state
         */
	for (data.buttons = i = 0; i < 32 && i < joydev->nkey; i++)
		data.buttons |=
			test_bit(joydev->keypam[i], input->key) ? (1 << i) : 0;
	data.x = (joydev->abs[0] / 256 + 128) >> joydev->glue.JS_CORR.x;
	data.y = (joydev->abs[1] / 256 + 128) >> joydev->glue.JS_CORR.y;

	/*
         * Reset reader's event queue
         */
	spin_lock(&client->buffer_lock);
	client->startup = 0;
	client->tail = client->head;
	spin_unlock(&client->buffer_lock);

	spin_unlock_irq(&input->event_lock);

	if (copy_to_user(buf, &data, sizeof(struct JS_DATA_TYPE)))
		return -EFAULT;

	return sizeof(struct JS_DATA_TYPE);
}

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Linus Torvalds (pre-git)
93
44.08%
2
33.33%
Dmitry Torokhov
91
43.13%
2
33.33%
Linus Torvalds
26
12.32%
1
16.67%
Al Viro
1
0.47%
1
16.67%
Total
211
100.00%
6
100.00%



static inline int joydev_data_pending(struct joydev_client *client)
{
	struct joydev *joydev = client->joydev;

	return client->startup < joydev->nabs + joydev->nkey ||
		client->head != client->tail;
}

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42
100.00%
1
100.00%
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42
100.00%
1
100.00%



static ssize_t joydev_read(struct file *file, char __user *buf,
			   size_t count, loff_t *ppos)
{
	struct joydev_client *client = file->private_data;
	struct joydev *joydev = client->joydev;
	struct input_dev *input = joydev->handle.dev;
	struct js_event event;
	int retval;

	if (!joydev->exist)
		return -ENODEV;

	if (count < sizeof(struct js_event))
		return -EINVAL;

	if (count == sizeof(struct JS_DATA_TYPE))
		return joydev_0x_read(client, input, buf);

	if (!joydev_data_pending(client) && (file->f_flags & O_NONBLOCK))
		return -EAGAIN;

	retval = wait_event_interruptible(joydev->wait,
			!joydev->exist || joydev_data_pending(client));
	if (retval)
		return retval;

	if (!joydev->exist)
		return -ENODEV;

	while (retval + sizeof(struct js_event) <= count &&
	       joydev_generate_startup_event(client, input, &event)) {

		if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
			return -EFAULT;

		retval += sizeof(struct js_event);
	}

	while (retval + sizeof(struct js_event) <= count &&
	       joydev_fetch_next_event(client, &event)) {

		if (copy_to_user(buf + retval, &event, sizeof(struct js_event)))
			return -EFAULT;

		retval += sizeof(struct js_event);
	}

	return retval;
}

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Linus Torvalds (pre-git)
131
48.52%
1
16.67%
Dmitry Torokhov
117
43.33%
3
50.00%
Vojtech Pavlik
22
8.15%
2
33.33%
Total
270
100.00%
6
100.00%

/* No kernel lock - fine */


static unsigned int joydev_poll(struct file *file, poll_table *wait)
{
	struct joydev_client *client = file->private_data;
	struct joydev *joydev = client->joydev;

	poll_wait(file, &joydev->wait, wait);
	return (joydev_data_pending(client) ? (POLLIN | POLLRDNORM) : 0) |
		(joydev->exist ?  0 : (POLLHUP | POLLERR));
}

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Linus Torvalds (pre-git)
40
52.63%
1
25.00%
Vojtech Pavlik
21
27.63%
1
25.00%
Dmitry Torokhov
15
19.74%
2
50.00%
Total
76
100.00%
4
100.00%



static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
				     void __user *argp, size_t len)
{
	__u8 *abspam;
	int i;
	int retval = 0;

	len = min(len, sizeof(joydev->abspam));

	/* Validate the map. */
	abspam = memdup_user(argp, len);
	if (IS_ERR(abspam))
		return PTR_ERR(abspam);

	for (i = 0; i < joydev->nabs; i++) {
		if (abspam[i] > ABS_MAX) {
			retval = -EINVAL;
			goto out;
		}
	}

	memcpy(joydev->abspam, abspam, len);

	for (i = 0; i < joydev->nabs; i++)
		joydev->absmap[joydev->abspam[i]] = i;

 out:
	kfree(abspam);
	return retval;
}

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Stephen Kitt
115
74.68%
1
25.00%
Kenneth Waters
29
18.83%
1
25.00%
Javier Martinez Canillas
10
6.49%
2
50.00%
Total
154
100.00%
4
100.00%



static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
				      void __user *argp, size_t len)
{
	__u16 *keypam;
	int i;
	int retval = 0;

	len = min(len, sizeof(joydev->keypam));

	/* Validate the map. */
	keypam = memdup_user(argp, len);
	if (IS_ERR(keypam))
		return PTR_ERR(keypam);

	for (i = 0; i < joydev->nkey; i++) {
		if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
			retval = -EINVAL;
			goto out;
		}
	}

	memcpy(joydev->keypam, keypam, len);

	for (i = 0; i < joydev->nkey; i++)
		joydev->keymap[keypam[i] - BTN_MISC] = i;

 out:
	kfree(keypam);
	return retval;
}


Contributors
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Stephen Kitt
151
93.79%
1
33.33%
Javier Martinez Canillas
10
6.21%
2
66.67%
Total
161
100.00%
3
100.00%



static int joydev_ioctl_common(struct joydev *joydev,
				unsigned int cmd, void __user *argp)
{
	struct input_dev *dev = joydev->handle.dev;
	size_t len;
	int i;
	const char *name;

	/* Process fixed-sized commands. */
	switch (cmd) {

	case JS_SET_CAL:
		return copy_from_user(&joydev->glue.JS_CORR, argp,
				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;

	case JS_GET_CAL:
		return copy_to_user(argp, &joydev->glue.JS_CORR,
				sizeof(joydev->glue.JS_CORR)) ? -EFAULT : 0;

	case JS_SET_TIMEOUT:
		return get_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);

	case JS_GET_TIMEOUT:
		return put_user(joydev->glue.JS_TIMEOUT, (s32 __user *) argp);

	case JSIOCGVERSION:
		return put_user(JS_VERSION, (__u32 __user *) argp);

	case JSIOCGAXES:
		return put_user(joydev->nabs, (__u8 __user *) argp);

	case JSIOCGBUTTONS:
		return put_user(joydev->nkey, (__u8 __user *) argp);

	case JSIOCSCORR:
		if (copy_from_user(joydev->corr, argp,
			      sizeof(joydev->corr[0]) * joydev->nabs))
			return -EFAULT;

		for (i = 0; i < joydev->nabs; i++) {
			int val = input_abs_get_val(dev, joydev->abspam[i]);
			joydev->abs[i] = joydev_correct(val, &joydev->corr[i]);
		}
		return 0;

	case JSIOCGCORR:
		return copy_to_user(argp, joydev->corr,
			sizeof(joydev->corr[0]) * joydev->nabs) ? -EFAULT : 0;

	}

	/*
         * Process variable-sized commands (the axis and button map commands
         * are considered variable-sized to decouple them from the values of
         * ABS_MAX and KEY_MAX).
         */
	switch (cmd & ~IOCSIZE_MASK) {

	case (JSIOCSAXMAP & ~IOCSIZE_MASK):
		return joydev_handle_JSIOCSAXMAP(joydev, argp, _IOC_SIZE(cmd));

	case (JSIOCGAXMAP & ~IOCSIZE_MASK):
		len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->abspam));
		return copy_to_user(argp, joydev->abspam, len) ? -EFAULT : len;

	case (JSIOCSBTNMAP & ~IOCSIZE_MASK):
		return joydev_handle_JSIOCSBTNMAP(joydev, argp, _IOC_SIZE(cmd));

	case (JSIOCGBTNMAP & ~IOCSIZE_MASK):
		len = min_t(size_t, _IOC_SIZE(cmd), sizeof(joydev->keypam));
		return copy_to_user(argp, joydev->keypam, len) ? -EFAULT : len;

	case JSIOCGNAME(0):
		name = dev->name;
		if (!name)
			return 0;

		len = min_t(size_t, _IOC_SIZE(cmd), strlen(name) + 1);
		return copy_to_user(argp, name, len) ? -EFAULT : len;
	}

	return -EINVAL;
}

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Linus Torvalds (pre-git)
242
46.72%
2
16.67%
Stephen Kitt
119
22.97%
2
16.67%
Linus Torvalds
47
9.07%
1
8.33%
Glenn Burkhardt
45
8.69%
1
8.33%
Jeremy Fitzhardinge
35
6.76%
1
8.33%
Al Viro
13
2.51%
1
8.33%
Daniel Mack
11
2.12%
2
16.67%
Thadeu Lima de Souza Cascardo
3
0.58%
1
8.33%
Dmitry Torokhov
3
0.58%
1
8.33%
Total
518
100.00%
12
100.00%

#ifdef CONFIG_COMPAT


static long joydev_compat_ioctl(struct file *file,
				unsigned int cmd, unsigned long arg)
{
	struct joydev_client *client = file->private_data;
	struct joydev *joydev = client->joydev;
	void __user *argp = (void __user *)arg;
	s32 tmp32;
	struct JS_DATA_SAVE_TYPE_32 ds32;
	int retval;

	retval = mutex_lock_interruptible(&joydev