linux-stable/drivers/input/mousedev.c
Dmitry Torokhov e4dbedc7ea Input: mousedev - fix race when creating mixed device
We should not be using static variable mousedev_mix in methods that can be
called before that singleton gets assigned. While at it let's add open and
close methods to mousedev structure so that we do not need to test if we
are dealing with multiplexor or normal device and simply call appropriate
method directly.

This fixes: https://bugzilla.kernel.org/show_bug.cgi?id=71551

Reported-by: GiulioDP <depasquale.giulio@gmail.com>
Tested-by: GiulioDP <depasquale.giulio@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-03-29 14:44:23 -07:00

1128 lines
26 KiB
C

/*
* Input driver to ExplorerPS/2 device driver module.
*
* Copyright (c) 1999-2002 Vojtech Pavlik
* Copyright (c) 2004 Dmitry Torokhov
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#define MOUSEDEV_MINOR_BASE 32
#define MOUSEDEV_MINORS 31
#define MOUSEDEV_MIX 63
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/random.h>
#include <linux/major.h>
#include <linux/device.h>
#include <linux/cdev.h>
#include <linux/kernel.h>
MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces");
MODULE_LICENSE("GPL");
#ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X
#define CONFIG_INPUT_MOUSEDEV_SCREEN_X 1024
#endif
#ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y
#define CONFIG_INPUT_MOUSEDEV_SCREEN_Y 768
#endif
static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
module_param(xres, uint, 0644);
MODULE_PARM_DESC(xres, "Horizontal screen resolution");
static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
module_param(yres, uint, 0644);
MODULE_PARM_DESC(yres, "Vertical screen resolution");
static unsigned tap_time = 200;
module_param(tap_time, uint, 0644);
MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)");
struct mousedev_hw_data {
int dx, dy, dz;
int x, y;
int abs_event;
unsigned long buttons;
};
struct mousedev {
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 list_head mixdev_node;
bool opened_by_mixdev;
struct mousedev_hw_data packet;
unsigned int pkt_count;
int old_x[4], old_y[4];
int frac_dx, frac_dy;
unsigned long touch;
int (*open_device)(struct mousedev *mousedev);
void (*close_device)(struct mousedev *mousedev);
};
enum mousedev_emul {
MOUSEDEV_EMUL_PS2,
MOUSEDEV_EMUL_IMPS,
MOUSEDEV_EMUL_EXPS
};
struct mousedev_motion {
int dx, dy, dz;
unsigned long buttons;
};
#define PACKET_QUEUE_LEN 16
struct mousedev_client {
struct fasync_struct *fasync;
struct mousedev *mousedev;
struct list_head node;
struct mousedev_motion packets[PACKET_QUEUE_LEN];
unsigned int head, tail;
spinlock_t packet_lock;
int pos_x, pos_y;
signed char ps2[6];
unsigned char ready, buffer, bufsiz;
unsigned char imexseq, impsseq;
enum mousedev_emul mode;
unsigned long last_buttons;
};
#define MOUSEDEV_SEQ_LEN 6
static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
static struct mousedev *mousedev_mix;
static LIST_HEAD(mousedev_mix_list);
#define fx(i) (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
#define fy(i) (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
static void mousedev_touchpad_event(struct input_dev *dev,
struct mousedev *mousedev,
unsigned int code, int value)
{
int size, tmp;
enum { FRACTION_DENOM = 128 };
switch (code) {
case ABS_X:
fx(0) = value;
if (mousedev->touch && mousedev->pkt_count >= 2) {
size = input_abs_get_max(dev, ABS_X) -
input_abs_get_min(dev, ABS_X);
if (size == 0)
size = 256 * 2;
tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size;
tmp += mousedev->frac_dx;
mousedev->packet.dx = tmp / FRACTION_DENOM;
mousedev->frac_dx =
tmp - mousedev->packet.dx * FRACTION_DENOM;
}
break;
case ABS_Y:
fy(0) = value;
if (mousedev->touch && mousedev->pkt_count >= 2) {
/* use X size for ABS_Y to keep the same scale */
size = input_abs_get_max(dev, ABS_X) -
input_abs_get_min(dev, ABS_X);
if (size == 0)
size = 256 * 2;
tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
tmp += mousedev->frac_dy;
mousedev->packet.dy = tmp / FRACTION_DENOM;
mousedev->frac_dy = tmp -
mousedev->packet.dy * FRACTION_DENOM;
}
break;
}
}
static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
unsigned int code, int value)
{
int min, max, size;
switch (code) {
case ABS_X:
min = input_abs_get_min(dev, ABS_X);
max = input_abs_get_max(dev, ABS_X);
size = max - min;
if (size == 0)
size = xres ? : 1;
value = clamp(value, min, max);
mousedev->packet.x = ((value - min) * xres) / size;
mousedev->packet.abs_event = 1;
break;
case ABS_Y:
min = input_abs_get_min(dev, ABS_Y);
max = input_abs_get_max(dev, ABS_Y);
size = max - min;
if (size == 0)
size = yres ? : 1;
value = clamp(value, min, max);
mousedev->packet.y = yres - ((value - min) * yres) / size;
mousedev->packet.abs_event = 1;
break;
}
}
static void mousedev_rel_event(struct mousedev *mousedev,
unsigned int code, int value)
{
switch (code) {
case REL_X:
mousedev->packet.dx += value;
break;
case REL_Y:
mousedev->packet.dy -= value;
break;
case REL_WHEEL:
mousedev->packet.dz -= value;
break;
}
}
static void mousedev_key_event(struct mousedev *mousedev,
unsigned int code, int value)
{
int index;
switch (code) {
case BTN_TOUCH:
case BTN_0:
case BTN_LEFT: index = 0; break;
case BTN_STYLUS:
case BTN_1:
case BTN_RIGHT: index = 1; break;
case BTN_2:
case BTN_FORWARD:
case BTN_STYLUS2:
case BTN_MIDDLE: index = 2; break;
case BTN_3:
case BTN_BACK:
case BTN_SIDE: index = 3; break;
case BTN_4:
case BTN_EXTRA: index = 4; break;
default: return;
}
if (value) {
set_bit(index, &mousedev->packet.buttons);
set_bit(index, &mousedev_mix->packet.buttons);
} else {
clear_bit(index, &mousedev->packet.buttons);
clear_bit(index, &mousedev_mix->packet.buttons);
}
}
static void mousedev_notify_readers(struct mousedev *mousedev,
struct mousedev_hw_data *packet)
{
struct mousedev_client *client;
struct mousedev_motion *p;
unsigned int new_head;
int wake_readers = 0;
rcu_read_lock();
list_for_each_entry_rcu(client, &mousedev->client_list, node) {
/* Just acquire the lock, interrupts already disabled */
spin_lock(&client->packet_lock);
p = &client->packets[client->head];
if (client->ready && p->buttons != mousedev->packet.buttons) {
new_head = (client->head + 1) % PACKET_QUEUE_LEN;
if (new_head != client->tail) {
p = &client->packets[client->head = new_head];
memset(p, 0, sizeof(struct mousedev_motion));
}
}
if (packet->abs_event) {
p->dx += packet->x - client->pos_x;
p->dy += packet->y - client->pos_y;
client->pos_x = packet->x;
client->pos_y = packet->y;
}
client->pos_x += packet->dx;
client->pos_x = client->pos_x < 0 ?
0 : (client->pos_x >= xres ? xres : client->pos_x);
client->pos_y += packet->dy;
client->pos_y = client->pos_y < 0 ?
0 : (client->pos_y >= yres ? yres : client->pos_y);
p->dx += packet->dx;
p->dy += packet->dy;
p->dz += packet->dz;
p->buttons = mousedev->packet.buttons;
if (p->dx || p->dy || p->dz ||
p->buttons != client->last_buttons)
client->ready = 1;
spin_unlock(&client->packet_lock);
if (client->ready) {
kill_fasync(&client->fasync, SIGIO, POLL_IN);
wake_readers = 1;
}
}
rcu_read_unlock();
if (wake_readers)
wake_up_interruptible(&mousedev->wait);
}
static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
{
if (!value) {
if (mousedev->touch &&
time_before(jiffies,
mousedev->touch + msecs_to_jiffies(tap_time))) {
/*
* Toggle left button to emulate tap.
* We rely on the fact that mousedev_mix always has 0
* motion packet so we won't mess current position.
*/
set_bit(0, &mousedev->packet.buttons);
set_bit(0, &mousedev_mix->packet.buttons);
mousedev_notify_readers(mousedev, &mousedev_mix->packet);
mousedev_notify_readers(mousedev_mix,
&mousedev_mix->packet);
clear_bit(0, &mousedev->packet.buttons);
clear_bit(0, &mousedev_mix->packet.buttons);
}
mousedev->touch = mousedev->pkt_count = 0;
mousedev->frac_dx = 0;
mousedev->frac_dy = 0;
} else if (!mousedev->touch)
mousedev->touch = jiffies;
}
static void mousedev_event(struct input_handle *handle,
unsigned int type, unsigned int code, int value)
{
struct mousedev *mousedev = handle->private;
switch (type) {
case EV_ABS:
/* Ignore joysticks */
if (test_bit(BTN_TRIGGER, handle->dev->keybit))
return;
if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
mousedev_touchpad_event(handle->dev,
mousedev, code, value);
else
mousedev_abs_event(handle->dev, mousedev, code, value);
break;
case EV_REL:
mousedev_rel_event(mousedev, code, value);
break;
case EV_KEY:
if (value != 2) {
if (code == BTN_TOUCH &&
test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
mousedev_touchpad_touch(mousedev, value);
else
mousedev_key_event(mousedev, code, value);
}
break;
case EV_SYN:
if (code == SYN_REPORT) {
if (mousedev->touch) {
mousedev->pkt_count++;
/*
* Input system eats duplicate events,
* but we need all of them to do correct
* averaging so apply present one forward
*/
fx(0) = fx(1);
fy(0) = fy(1);
}
mousedev_notify_readers(mousedev, &mousedev->packet);
mousedev_notify_readers(mousedev_mix, &mousedev->packet);
mousedev->packet.dx = mousedev->packet.dy =
mousedev->packet.dz = 0;
mousedev->packet.abs_event = 0;
}
break;
}
}
static int mousedev_fasync(int fd, struct file *file, int on)
{
struct mousedev_client *client = file->private_data;
return fasync_helper(fd, file, on, &client->fasync);
}
static void mousedev_free(struct device *dev)
{
struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
input_put_device(mousedev->handle.dev);
kfree(mousedev);
}
static int mousedev_open_device(struct mousedev *mousedev)
{
int retval;
retval = mutex_lock_interruptible(&mousedev->mutex);
if (retval)
return retval;
if (!mousedev->exist)
retval = -ENODEV;
else if (!mousedev->open++) {
retval = input_open_device(&mousedev->handle);
if (retval)
mousedev->open--;
}
mutex_unlock(&mousedev->mutex);
return retval;
}
static void mousedev_close_device(struct mousedev *mousedev)
{
mutex_lock(&mousedev->mutex);
if (mousedev->exist && !--mousedev->open)
input_close_device(&mousedev->handle);
mutex_unlock(&mousedev->mutex);
}
/*
* Open all available devices so they can all be multiplexed in one.
* stream. Note that this function is called with mousedev_mix->mutex
* held.
*/
static int mixdev_open_devices(struct mousedev *mixdev)
{
int error;
error = mutex_lock_interruptible(&mixdev->mutex);
if (error)
return error;
if (!mixdev->open++) {
struct mousedev *mousedev;
list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
if (!mousedev->opened_by_mixdev) {
if (mousedev_open_device(mousedev))
continue;
mousedev->opened_by_mixdev = true;
}
}
}
mutex_unlock(&mixdev->mutex);
return 0;
}
/*
* Close all devices that were opened as part of multiplexed
* device. Note that this function is called with mousedev_mix->mutex
* held.
*/
static void mixdev_close_devices(struct mousedev *mixdev)
{
mutex_lock(&mixdev->mutex);
if (!--mixdev->open) {
struct mousedev *mousedev;
list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
if (mousedev->opened_by_mixdev) {
mousedev->opened_by_mixdev = false;
mousedev_close_device(mousedev);
}
}
}
mutex_unlock(&mixdev->mutex);
}
static void mousedev_attach_client(struct mousedev *mousedev,
struct mousedev_client *client)
{
spin_lock(&mousedev->client_lock);
list_add_tail_rcu(&client->node, &mousedev->client_list);
spin_unlock(&mousedev->client_lock);
}
static void mousedev_detach_client(struct mousedev *mousedev,
struct mousedev_client *client)
{
spin_lock(&mousedev->client_lock);
list_del_rcu(&client->node);
spin_unlock(&mousedev->client_lock);
synchronize_rcu();
}
static int mousedev_release(struct inode *inode, struct file *file)
{
struct mousedev_client *client = file->private_data;
struct mousedev *mousedev = client->mousedev;
mousedev_detach_client(mousedev, client);
kfree(client);
mousedev->close_device(mousedev);
return 0;
}
static int mousedev_open(struct inode *inode, struct file *file)
{
struct mousedev_client *client;
struct mousedev *mousedev;
int error;
#ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
if (imajor(inode) == MISC_MAJOR)
mousedev = mousedev_mix;
else
#endif
mousedev = container_of(inode->i_cdev, struct mousedev, cdev);
client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
if (!client)
return -ENOMEM;
spin_lock_init(&client->packet_lock);
client->pos_x = xres / 2;
client->pos_y = yres / 2;
client->mousedev = mousedev;
mousedev_attach_client(mousedev, client);
error = mousedev->open_device(mousedev);
if (error)
goto err_free_client;
file->private_data = client;
nonseekable_open(inode, file);
return 0;
err_free_client:
mousedev_detach_client(mousedev, client);
kfree(client);
return error;
}
static inline int mousedev_limit_delta(int delta, int limit)
{
return delta > limit ? limit : (delta < -limit ? -limit : delta);
}
static void mousedev_packet(struct mousedev_client *client,
signed char *ps2_data)
{
struct mousedev_motion *p = &client->packets[client->tail];
ps2_data[0] = 0x08 |
((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
ps2_data[1] = mousedev_limit_delta(p->dx, 127);
ps2_data[2] = mousedev_limit_delta(p->dy, 127);
p->dx -= ps2_data[1];
p->dy -= ps2_data[2];
switch (client->mode) {
case MOUSEDEV_EMUL_EXPS:
ps2_data[3] = mousedev_limit_delta(p->dz, 7);
p->dz -= ps2_data[3];
ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
client->bufsiz = 4;
break;
case MOUSEDEV_EMUL_IMPS:
ps2_data[0] |=
((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
ps2_data[3] = mousedev_limit_delta(p->dz, 127);
p->dz -= ps2_data[3];
client->bufsiz = 4;
break;
case MOUSEDEV_EMUL_PS2:
default:
ps2_data[0] |=
((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
p->dz = 0;
client->bufsiz = 3;
break;
}
if (!p->dx && !p->dy && !p->dz) {
if (client->tail == client->head) {
client->ready = 0;
client->last_buttons = p->buttons;
} else
client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
}
}
static void mousedev_generate_response(struct mousedev_client *client,
int command)
{
client->ps2[0] = 0xfa; /* ACK */
switch (command) {
case 0xeb: /* Poll */
mousedev_packet(client, &client->ps2[1]);
client->bufsiz++; /* account for leading ACK */
break;
case 0xf2: /* Get ID */
switch (client->mode) {
case MOUSEDEV_EMUL_PS2:
client->ps2[1] = 0;
break;
case MOUSEDEV_EMUL_IMPS:
client->ps2[1] = 3;
break;
case MOUSEDEV_EMUL_EXPS:
client->ps2[1] = 4;
break;
}
client->bufsiz = 2;
break;
case 0xe9: /* Get info */
client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
client->bufsiz = 4;
break;
case 0xff: /* Reset */
client->impsseq = client->imexseq = 0;
client->mode = MOUSEDEV_EMUL_PS2;
client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
client->bufsiz = 3;
break;
default:
client->bufsiz = 1;
break;
}
client->buffer = client->bufsiz;
}
static ssize_t mousedev_write(struct file *file, const char __user *buffer,
size_t count, loff_t *ppos)
{
struct mousedev_client *client = file->private_data;
unsigned char c;
unsigned int i;
for (i = 0; i < count; i++) {
if (get_user(c, buffer + i))
return -EFAULT;
spin_lock_irq(&client->packet_lock);
if (c == mousedev_imex_seq[client->imexseq]) {
if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
client->imexseq = 0;
client->mode = MOUSEDEV_EMUL_EXPS;
}
} else
client->imexseq = 0;
if (c == mousedev_imps_seq[client->impsseq]) {
if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
client->impsseq = 0;
client->mode = MOUSEDEV_EMUL_IMPS;
}
} else
client->impsseq = 0;
mousedev_generate_response(client, c);
spin_unlock_irq(&client->packet_lock);
}
kill_fasync(&client->fasync, SIGIO, POLL_IN);
wake_up_interruptible(&client->mousedev->wait);
return count;
}
static ssize_t mousedev_read(struct file *file, char __user *buffer,
size_t count, loff_t *ppos)
{
struct mousedev_client *client = file->private_data;
struct mousedev *mousedev = client->mousedev;
signed char data[sizeof(client->ps2)];
int retval = 0;
if (!client->ready && !client->buffer && mousedev->exist &&
(file->f_flags & O_NONBLOCK))
return -EAGAIN;
retval = wait_event_interruptible(mousedev->wait,
!mousedev->exist || client->ready || client->buffer);
if (retval)
return retval;
if (!mousedev->exist)
return -ENODEV;
spin_lock_irq(&client->packet_lock);
if (!client->buffer && client->ready) {
mousedev_packet(client, client->ps2);
client->buffer = client->bufsiz;
}
if (count > client->buffer)
count = client->buffer;
memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
client->buffer -= count;
spin_unlock_irq(&client->packet_lock);
if (copy_to_user(buffer, data, count))
return -EFAULT;
return count;
}
/* No kernel lock - fine */
static unsigned int mousedev_poll(struct file *file, poll_table *wait)
{
struct mousedev_client *client = file->private_data;
struct mousedev *mousedev = client->mousedev;
unsigned int mask;
poll_wait(file, &mousedev->wait, wait);
mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
if (client->ready || client->buffer)
mask |= POLLIN | POLLRDNORM;
return mask;
}
static const struct file_operations mousedev_fops = {
.owner = THIS_MODULE,
.read = mousedev_read,
.write = mousedev_write,
.poll = mousedev_poll,
.open = mousedev_open,
.release = mousedev_release,
.fasync = mousedev_fasync,
.llseek = noop_llseek,
};
/*
* Mark device non-existent. This disables writes, ioctls and
* prevents new users from opening the device. Already posted
* blocking reads will stay, however new ones will fail.
*/
static void mousedev_mark_dead(struct mousedev *mousedev)
{
mutex_lock(&mousedev->mutex);
mousedev->exist = false;
mutex_unlock(&mousedev->mutex);
}
/*
* Wake up users waiting for IO so they can disconnect from
* dead device.
*/
static void mousedev_hangup(struct mousedev *mousedev)
{
struct mousedev_client *client;
spin_lock(&mousedev->client_lock);
list_for_each_entry(client, &mousedev->client_list, node)
kill_fasync(&client->fasync, SIGIO, POLL_HUP);
spin_unlock(&mousedev->client_lock);
wake_up_interruptible(&mousedev->wait);
}
static void mousedev_cleanup(struct mousedev *mousedev)
{
struct input_handle *handle = &mousedev->handle;
mousedev_mark_dead(mousedev);
mousedev_hangup(mousedev);
cdev_del(&mousedev->cdev);
/* mousedev is marked dead so no one else accesses mousedev->open */
if (mousedev->open)
input_close_device(handle);
}
static int mousedev_reserve_minor(bool mixdev)
{
int minor;
if (mixdev) {
minor = input_get_new_minor(MOUSEDEV_MIX, 1, false);
if (minor < 0)
pr_err("failed to reserve mixdev minor: %d\n", minor);
} else {
minor = input_get_new_minor(MOUSEDEV_MINOR_BASE,
MOUSEDEV_MINORS, true);
if (minor < 0)
pr_err("failed to reserve new minor: %d\n", minor);
}
return minor;
}
static struct mousedev *mousedev_create(struct input_dev *dev,
struct input_handler *handler,
bool mixdev)
{
struct mousedev *mousedev;
int minor;
int error;
minor = mousedev_reserve_minor(mixdev);
if (minor < 0) {
error = minor;
goto err_out;
}
mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
if (!mousedev) {
error = -ENOMEM;
goto err_free_minor;
}
INIT_LIST_HEAD(&mousedev->client_list);
INIT_LIST_HEAD(&mousedev->mixdev_node);
spin_lock_init(&mousedev->client_lock);
mutex_init(&mousedev->mutex);
lockdep_set_subclass(&mousedev->mutex,
mixdev ? SINGLE_DEPTH_NESTING : 0);
init_waitqueue_head(&mousedev->wait);
if (mixdev) {
dev_set_name(&mousedev->dev, "mice");
mousedev->open_device = mixdev_open_devices;
mousedev->close_device = mixdev_close_devices;
} else {
int dev_no = minor;
/* Normalize device number if it falls into legacy range */
if (dev_no < MOUSEDEV_MINOR_BASE + MOUSEDEV_MINORS)
dev_no -= MOUSEDEV_MINOR_BASE;
dev_set_name(&mousedev->dev, "mouse%d", dev_no);
mousedev->open_device = mousedev_open_device;
mousedev->close_device = mousedev_close_device;
}
mousedev->exist = true;
mousedev->handle.dev = input_get_device(dev);
mousedev->handle.name = dev_name(&mousedev->dev);
mousedev->handle.handler = handler;
mousedev->handle.private = mousedev;
mousedev->dev.class = &input_class;
if (dev)
mousedev->dev.parent = &dev->dev;
mousedev->dev.devt = MKDEV(INPUT_MAJOR, minor);
mousedev->dev.release = mousedev_free;
device_initialize(&mousedev->dev);
if (!mixdev) {
error = input_register_handle(&mousedev->handle);
if (error)
goto err_free_mousedev;
}
cdev_init(&mousedev->cdev, &mousedev_fops);
mousedev->cdev.kobj.parent = &mousedev->dev.kobj;
error = cdev_add(&mousedev->cdev, mousedev->dev.devt, 1);
if (error)
goto err_unregister_handle;
error = device_add(&mousedev->dev);
if (error)
goto err_cleanup_mousedev;
return mousedev;
err_cleanup_mousedev:
mousedev_cleanup(mousedev);
err_unregister_handle:
if (!mixdev)
input_unregister_handle(&mousedev->handle);
err_free_mousedev:
put_device(&mousedev->dev);
err_free_minor:
input_free_minor(minor);
err_out:
return ERR_PTR(error);
}
static void mousedev_destroy(struct mousedev *mousedev)
{
device_del(&mousedev->dev);
mousedev_cleanup(mousedev);
input_free_minor(MINOR(mousedev->dev.devt));
if (mousedev != mousedev_mix)
input_unregister_handle(&mousedev->handle);
put_device(&mousedev->dev);
}
static int mixdev_add_device(struct mousedev *mousedev)
{
int retval;
retval = mutex_lock_interruptible(&mousedev_mix->mutex);
if (retval)
return retval;
if (mousedev_mix->open) {
retval = mousedev_open_device(mousedev);
if (retval)
goto out;
mousedev->opened_by_mixdev = true;
}
get_device(&mousedev->dev);
list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
out:
mutex_unlock(&mousedev_mix->mutex);
return retval;
}
static void mixdev_remove_device(struct mousedev *mousedev)
{
mutex_lock(&mousedev_mix->mutex);
if (mousedev->opened_by_mixdev) {
mousedev->opened_by_mixdev = false;
mousedev_close_device(mousedev);
}
list_del_init(&mousedev->mixdev_node);
mutex_unlock(&mousedev_mix->mutex);
put_device(&mousedev->dev);
}
static int mousedev_connect(struct input_handler *handler,
struct input_dev *dev,
const struct input_device_id *id)
{
struct mousedev *mousedev;
int error;
mousedev = mousedev_create(dev, handler, false);
if (IS_ERR(mousedev))
return PTR_ERR(mousedev);
error = mixdev_add_device(mousedev);
if (error) {
mousedev_destroy(mousedev);
return error;
}
return 0;
}
static void mousedev_disconnect(struct input_handle *handle)
{
struct mousedev *mousedev = handle->private;
mixdev_remove_device(mousedev);
mousedev_destroy(mousedev);
}
static const struct input_device_id mousedev_ids[] = {
{
.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
INPUT_DEVICE_ID_MATCH_KEYBIT |
INPUT_DEVICE_ID_MATCH_RELBIT,
.evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
.keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
.relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
}, /* A mouse like device, at least one button,
two relative axes */
{
.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
INPUT_DEVICE_ID_MATCH_RELBIT,
.evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
.relbit = { BIT_MASK(REL_WHEEL) },
}, /* A separate scrollwheel */
{
.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
INPUT_DEVICE_ID_MATCH_KEYBIT |
INPUT_DEVICE_ID_MATCH_ABSBIT,
.evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
.keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
.absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
}, /* A tablet like device, at least touch detection,
two absolute axes */
{
.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
INPUT_DEVICE_ID_MATCH_KEYBIT |
INPUT_DEVICE_ID_MATCH_ABSBIT,
.evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
.keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
BIT_MASK(BTN_TOOL_FINGER) },
.absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
BIT_MASK(ABS_PRESSURE) |
BIT_MASK(ABS_TOOL_WIDTH) },
}, /* A touchpad */
{
.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
INPUT_DEVICE_ID_MATCH_KEYBIT |
INPUT_DEVICE_ID_MATCH_ABSBIT,
.evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
.keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
.absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
}, /* Mouse-like device with absolute X and Y but ordinary
clicks, like hp ILO2 High Performance mouse */
{ }, /* Terminating entry */
};
MODULE_DEVICE_TABLE(input, mousedev_ids);
static struct input_handler mousedev_handler = {
.event = mousedev_event,
.connect = mousedev_connect,
.disconnect = mousedev_disconnect,
.legacy_minors = true,
.minor = MOUSEDEV_MINOR_BASE,
.name = "mousedev",
.id_table = mousedev_ids,
};
#ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
#include <linux/miscdevice.h>
static struct miscdevice psaux_mouse = {
.minor = PSMOUSE_MINOR,
.name = "psaux",
.fops = &mousedev_fops,
};
static bool psaux_registered;
static void __init mousedev_psaux_register(void)
{
int error;
error = misc_register(&psaux_mouse);
if (error)
pr_warn("could not register psaux device, error: %d\n",
error);
else
psaux_registered = true;
}
static void __exit mousedev_psaux_unregister(void)
{
if (psaux_registered)
misc_deregister(&psaux_mouse);
}
#else
static inline void mousedev_psaux_register(void) { }
static inline void mousedev_psaux_unregister(void) { }
#endif
static int __init mousedev_init(void)
{
int error;
mousedev_mix = mousedev_create(NULL, &mousedev_handler, true);
if (IS_ERR(mousedev_mix))
return PTR_ERR(mousedev_mix);
error = input_register_handler(&mousedev_handler);
if (error) {
mousedev_destroy(mousedev_mix);
return error;
}
mousedev_psaux_register();
pr_info("PS/2 mouse device common for all mice\n");
return 0;
}
static void __exit mousedev_exit(void)
{
mousedev_psaux_unregister();
input_unregister_handler(&mousedev_handler);
mousedev_destroy(mousedev_mix);
}
module_init(mousedev_init);
module_exit(mousedev_exit);