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mousedev.c
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mousedev.c
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/*
* 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 <[email protected]>");
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;
bool is_mixdev;
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;
};
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);
static void mixdev_open_devices(void);
static void mixdev_close_devices(void);
#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->is_mixdev)
mixdev_open_devices();
else 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->is_mixdev)
mixdev_close_devices();
else 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 void mixdev_open_devices(void)
{
struct mousedev *mousedev;
if (mousedev_mix->open++)
return;
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;
}
}
}
/*
* 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(void)
{
struct mousedev *mousedev;
if (--mousedev_mix->open)
return;
list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
if (mousedev->opened_by_mixdev) {
mousedev->opened_by_mixdev = false;
mousedev_close_device(mousedev);
}
}
}
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");
} 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->exist = true;
mousedev->is_mixdev = mixdev;
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->is_mixdev)
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) },