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[/] [test_project/] [trunk/] [linux_sd_driver/] [drivers/] [input/] [evdev.c] - Blame information for rev 62

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/*
 * Event char devices, giving access to raw input device events.
 *
 * 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.
 */
 
#define EVDEV_MINOR_BASE        64
#define EVDEV_MINORS            32
#define EVDEV_BUFFER_SIZE       64
 
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/major.h>
#include <linux/device.h>
#include <linux/compat.h>
 
struct evdev {
        int exist;
        int open;
        int minor;
        char name[16];
        struct input_handle handle;
        wait_queue_head_t wait;
        struct evdev_client *grab;
        struct list_head client_list;
        spinlock_t client_lock; /* protects client_list */
        struct mutex mutex;
        struct device dev;
};
 
struct evdev_client {
        struct input_event buffer[EVDEV_BUFFER_SIZE];
        int head;
        int tail;
        spinlock_t buffer_lock; /* protects access to buffer, head and tail */
        struct fasync_struct *fasync;
        struct evdev *evdev;
        struct list_head node;
};
 
static struct evdev *evdev_table[EVDEV_MINORS];
static DEFINE_MUTEX(evdev_table_mutex);
 
static void evdev_pass_event(struct evdev_client *client,
                             struct input_event *event)
{
        /*
         * Interrupts are disabled, just acquire the lock
         */
        spin_lock(&client->buffer_lock);
        client->buffer[client->head++] = *event;
        client->head &= EVDEV_BUFFER_SIZE - 1;
        spin_unlock(&client->buffer_lock);
 
        kill_fasync(&client->fasync, SIGIO, POLL_IN);
}
 
/*
 * Pass incoming event to all connected clients.
 */
static void evdev_event(struct input_handle *handle,
                        unsigned int type, unsigned int code, int value)
{
        struct evdev *evdev = handle->private;
        struct evdev_client *client;
        struct input_event event;
 
        do_gettimeofday(&event.time);
        event.type = type;
        event.code = code;
        event.value = value;
 
        rcu_read_lock();
 
        client = rcu_dereference(evdev->grab);
        if (client)
                evdev_pass_event(client, &event);
        else
                list_for_each_entry_rcu(client, &evdev->client_list, node)
                        evdev_pass_event(client, &event);
 
        rcu_read_unlock();
 
        wake_up_interruptible(&evdev->wait);
}
 
static int evdev_fasync(int fd, struct file *file, int on)
{
        struct evdev_client *client = file->private_data;
        int retval;
 
        retval = fasync_helper(fd, file, on, &client->fasync);
 
        return retval < 0 ? retval : 0;
}
 
static int evdev_flush(struct file *file, fl_owner_t id)
{
        struct evdev_client *client = file->private_data;
        struct evdev *evdev = client->evdev;
        int retval;
 
        retval = mutex_lock_interruptible(&evdev->mutex);
        if (retval)
                return retval;
 
        if (!evdev->exist)
                retval = -ENODEV;
        else
                retval = input_flush_device(&evdev->handle, file);
 
        mutex_unlock(&evdev->mutex);
        return retval;
}
 
static void evdev_free(struct device *dev)
{
        struct evdev *evdev = container_of(dev, struct evdev, dev);
 
        kfree(evdev);
}
 
/*
 * Grabs an event device (along with underlying input device).
 * This function is called with evdev->mutex taken.
 */
static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
{
        int error;
 
        if (evdev->grab)
                return -EBUSY;
 
        error = input_grab_device(&evdev->handle);
        if (error)
                return error;
 
        rcu_assign_pointer(evdev->grab, client);
        synchronize_rcu();
 
        return 0;
}
 
static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
{
        if (evdev->grab != client)
                return  -EINVAL;
 
        rcu_assign_pointer(evdev->grab, NULL);
        synchronize_rcu();
        input_release_device(&evdev->handle);
 
        return 0;
}
 
static void evdev_attach_client(struct evdev *evdev,
                                struct evdev_client *client)
{
        spin_lock(&evdev->client_lock);
        list_add_tail_rcu(&client->node, &evdev->client_list);
        spin_unlock(&evdev->client_lock);
        synchronize_rcu();
}
 
static void evdev_detach_client(struct evdev *evdev,
                                struct evdev_client *client)
{
        spin_lock(&evdev->client_lock);
        list_del_rcu(&client->node);
        spin_unlock(&evdev->client_lock);
        synchronize_rcu();
}
 
static int evdev_open_device(struct evdev *evdev)
{
        int retval;
 
        retval = mutex_lock_interruptible(&evdev->mutex);
        if (retval)
                return retval;
 
        if (!evdev->exist)
                retval = -ENODEV;
        else if (!evdev->open++) {
                retval = input_open_device(&evdev->handle);
                if (retval)
                        evdev->open--;
        }
 
        mutex_unlock(&evdev->mutex);
        return retval;
}
 
static void evdev_close_device(struct evdev *evdev)
{
        mutex_lock(&evdev->mutex);
 
        if (evdev->exist && !--evdev->open)
                input_close_device(&evdev->handle);
 
        mutex_unlock(&evdev->mutex);
}
 
/*
 * Wake up users waiting for IO so they can disconnect from
 * dead device.
 */
static void evdev_hangup(struct evdev *evdev)
{
        struct evdev_client *client;
 
        spin_lock(&evdev->client_lock);
        list_for_each_entry(client, &evdev->client_list, node)
                kill_fasync(&client->fasync, SIGIO, POLL_HUP);
        spin_unlock(&evdev->client_lock);
 
        wake_up_interruptible(&evdev->wait);
}
 
static int evdev_release(struct inode *inode, struct file *file)
{
        struct evdev_client *client = file->private_data;
        struct evdev *evdev = client->evdev;
 
        mutex_lock(&evdev->mutex);
        if (evdev->grab == client)
                evdev_ungrab(evdev, client);
        mutex_unlock(&evdev->mutex);
 
        evdev_fasync(-1, file, 0);
        evdev_detach_client(evdev, client);
        kfree(client);
 
        evdev_close_device(evdev);
        put_device(&evdev->dev);
 
        return 0;
}
 
static int evdev_open(struct inode *inode, struct file *file)
{
        struct evdev *evdev;
        struct evdev_client *client;
        int i = iminor(inode) - EVDEV_MINOR_BASE;
        int error;
 
        if (i >= EVDEV_MINORS)
                return -ENODEV;
 
        error = mutex_lock_interruptible(&evdev_table_mutex);
        if (error)
                return error;
        evdev = evdev_table[i];
        if (evdev)
                get_device(&evdev->dev);
        mutex_unlock(&evdev_table_mutex);
 
        if (!evdev)
                return -ENODEV;
 
        client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
        if (!client) {
                error = -ENOMEM;
                goto err_put_evdev;
        }
 
        spin_lock_init(&client->buffer_lock);
        client->evdev = evdev;
        evdev_attach_client(evdev, client);
 
        error = evdev_open_device(evdev);
        if (error)
                goto err_free_client;
 
        file->private_data = client;
        return 0;
 
 err_free_client:
        evdev_detach_client(evdev, client);
        kfree(client);
 err_put_evdev:
        put_device(&evdev->dev);
        return error;
}
 
#ifdef CONFIG_COMPAT
 
struct input_event_compat {
        struct compat_timeval time;
        __u16 type;
        __u16 code;
        __s32 value;
};
 
/* Note to the author of this code: did it ever occur to
   you why the ifdefs are needed? Think about it again. -AK */
#ifdef CONFIG_X86_64
#  define COMPAT_TEST is_compat_task()
#elif defined(CONFIG_IA64)
#  define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
#elif defined(CONFIG_S390)
#  define COMPAT_TEST test_thread_flag(TIF_31BIT)
#elif defined(CONFIG_MIPS)
#  define COMPAT_TEST test_thread_flag(TIF_32BIT_ADDR)
#else
#  define COMPAT_TEST test_thread_flag(TIF_32BIT)
#endif
 
static inline size_t evdev_event_size(void)
{
        return COMPAT_TEST ?
                sizeof(struct input_event_compat) : sizeof(struct input_event);
}
 
static int evdev_event_from_user(const char __user *buffer,
                                 struct input_event *event)
{
        if (COMPAT_TEST) {
                struct input_event_compat compat_event;
 
                if (copy_from_user(&compat_event, buffer,
                                   sizeof(struct input_event_compat)))
                        return -EFAULT;
 
                event->time.tv_sec = compat_event.time.tv_sec;
                event->time.tv_usec = compat_event.time.tv_usec;
                event->type = compat_event.type;
                event->code = compat_event.code;
                event->value = compat_event.value;
 
        } else {
                if (copy_from_user(event, buffer, sizeof(struct input_event)))
                        return -EFAULT;
        }
 
        return 0;
}
 
static int evdev_event_to_user(char __user *buffer,
                                const struct input_event *event)
{
        if (COMPAT_TEST) {
                struct input_event_compat compat_event;
 
                compat_event.time.tv_sec = event->time.tv_sec;
                compat_event.time.tv_usec = event->time.tv_usec;
                compat_event.type = event->type;
                compat_event.code = event->code;
                compat_event.value = event->value;
 
                if (copy_to_user(buffer, &compat_event,
                                 sizeof(struct input_event_compat)))
                        return -EFAULT;
 
        } else {
                if (copy_to_user(buffer, event, sizeof(struct input_event)))
                        return -EFAULT;
        }
 
        return 0;
}
 
#else
 
static inline size_t evdev_event_size(void)
{
        return sizeof(struct input_event);
}
 
static int evdev_event_from_user(const char __user *buffer,
                                 struct input_event *event)
{
        if (copy_from_user(event, buffer, sizeof(struct input_event)))
                return -EFAULT;
 
        return 0;
}
 
static int evdev_event_to_user(char __user *buffer,
                                const struct input_event *event)
{
        if (copy_to_user(buffer, event, sizeof(struct input_event)))
                return -EFAULT;
 
        return 0;
}
 
#endif /* CONFIG_COMPAT */
 
static ssize_t evdev_write(struct file *file, const char __user *buffer,
                           size_t count, loff_t *ppos)
{
        struct evdev_client *client = file->private_data;
        struct evdev *evdev = client->evdev;
        struct input_event event;
        int retval;
 
        retval = mutex_lock_interruptible(&evdev->mutex);
        if (retval)
                return retval;
 
        if (!evdev->exist) {
                retval = -ENODEV;
                goto out;
        }
 
        while (retval < count) {
 
                if (evdev_event_from_user(buffer + retval, &event)) {
                        retval = -EFAULT;
                        goto out;
                }
 
                input_inject_event(&evdev->handle,
                                   event.type, event.code, event.value);
                retval += evdev_event_size();
        }
 
 out:
        mutex_unlock(&evdev->mutex);
        return retval;
}
 
static int evdev_fetch_next_event(struct evdev_client *client,
                                  struct input_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 &= EVDEV_BUFFER_SIZE - 1;
        }
 
        spin_unlock_irq(&client->buffer_lock);
 
        return have_event;
}
 
static ssize_t evdev_read(struct file *file, char __user *buffer,
                          size_t count, loff_t *ppos)
{
        struct evdev_client *client = file->private_data;
        struct evdev *evdev = client->evdev;
        struct input_event event;
        int retval;
 
        if (count < evdev_event_size())
                return -EINVAL;
 
        if (client->head == client->tail && evdev->exist &&
            (file->f_flags & O_NONBLOCK))
                return -EAGAIN;
 
        retval = wait_event_interruptible(evdev->wait,
                client->head != client->tail || !evdev->exist);
        if (retval)
                return retval;
 
        if (!evdev->exist)
                return -ENODEV;
 
        while (retval + evdev_event_size() <= count &&
               evdev_fetch_next_event(client, &event)) {
 
                if (evdev_event_to_user(buffer + retval, &event))
                        return -EFAULT;
 
                retval += evdev_event_size();
        }
 
        return retval;
}
 
/* No kernel lock - fine */
static unsigned int evdev_poll(struct file *file, poll_table *wait)
{
        struct evdev_client *client = file->private_data;
        struct evdev *evdev = client->evdev;
 
        poll_wait(file, &evdev->wait, wait);
        return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
                (evdev->exist ? 0 : (POLLHUP | POLLERR));
}
 
#ifdef CONFIG_COMPAT
 
#define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
#define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
 
#ifdef __BIG_ENDIAN
static int bits_to_user(unsigned long *bits, unsigned int maxbit,
                        unsigned int maxlen, void __user *p, int compat)
{
        int len, i;
 
        if (compat) {
                len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
                if (len > maxlen)
                        len = maxlen;
 
                for (i = 0; i < len / sizeof(compat_long_t); i++)
                        if (copy_to_user((compat_long_t __user *) p + i,
                                         (compat_long_t *) bits +
                                                i + 1 - ((i % 2) << 1),
                                         sizeof(compat_long_t)))
                                return -EFAULT;
        } else {
                len = BITS_TO_LONGS(maxbit) * sizeof(long);
                if (len > maxlen)
                        len = maxlen;
 
                if (copy_to_user(p, bits, len))
                        return -EFAULT;
        }
 
        return len;
}
#else
static int bits_to_user(unsigned long *bits, unsigned int maxbit,
                        unsigned int maxlen, void __user *p, int compat)
{
        int len = compat ?
                        BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
                        BITS_TO_LONGS(maxbit) * sizeof(long);
 
        if (len > maxlen)
                len = maxlen;
 
        return copy_to_user(p, bits, len) ? -EFAULT : len;
}
#endif /* __BIG_ENDIAN */
 
#else
 
static int bits_to_user(unsigned long *bits, unsigned int maxbit,
                        unsigned int maxlen, void __user *p, int compat)
{
        int len = BITS_TO_LONGS(maxbit) * sizeof(long);
 
        if (len > maxlen)
                len = maxlen;
 
        return copy_to_user(p, bits, len) ? -EFAULT : len;
}
 
#endif /* CONFIG_COMPAT */
 
static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
{
        int len;
 
        if (!str)
                return -ENOENT;
 
        len = strlen(str) + 1;
        if (len > maxlen)
                len = maxlen;
 
        return copy_to_user(p, str, len) ? -EFAULT : len;
}
 
static long evdev_do_ioctl(struct file *file, unsigned int cmd,
                           void __user *p, int compat_mode)
{
        struct evdev_client *client = file->private_data;
        struct evdev *evdev = client->evdev;
        struct input_dev *dev = evdev->handle.dev;
        struct input_absinfo abs;
        struct ff_effect effect;
        int __user *ip = (int __user *)p;
        int i, t, u, v;
        int error;
 
        switch (cmd) {
 
        case EVIOCGVERSION:
                return put_user(EV_VERSION, ip);
 
        case EVIOCGID:
                if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
                        return -EFAULT;
                return 0;
 
        case EVIOCGREP:
                if (!test_bit(EV_REP, dev->evbit))
                        return -ENOSYS;
                if (put_user(dev->rep[REP_DELAY], ip))
                        return -EFAULT;
                if (put_user(dev->rep[REP_PERIOD], ip + 1))
                        return -EFAULT;
                return 0;
 
        case EVIOCSREP:
                if (!test_bit(EV_REP, dev->evbit))
                        return -ENOSYS;
                if (get_user(u, ip))
                        return -EFAULT;
                if (get_user(v, ip + 1))
                        return -EFAULT;
 
                input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
                input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
 
                return 0;
 
        case EVIOCGKEYCODE:
                if (get_user(t, ip))
                        return -EFAULT;
 
                error = dev->getkeycode(dev, t, &v);
                if (error)
                        return error;
 
                if (put_user(v, ip + 1))
                        return -EFAULT;
 
                return 0;
 
        case EVIOCSKEYCODE:
                if (get_user(t, ip) || get_user(v, ip + 1))
                        return -EFAULT;
 
                return dev->setkeycode(dev, t, v);
 
        case EVIOCSFF:
                if (copy_from_user(&effect, p, sizeof(effect)))
                        return -EFAULT;
 
                error = input_ff_upload(dev, &effect, file);
 
                if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
                        return -EFAULT;
 
                return error;
 
        case EVIOCRMFF:
                return input_ff_erase(dev, (int)(unsigned long) p, file);
 
        case EVIOCGEFFECTS:
                i = test_bit(EV_FF, dev->evbit) ?
                                dev->ff->max_effects : 0;
                if (put_user(i, ip))
                        return -EFAULT;
                return 0;
 
        case EVIOCGRAB:
                if (p)
                        return evdev_grab(evdev, client);
                else
                        return evdev_ungrab(evdev, client);
 
        default:
 
                if (_IOC_TYPE(cmd) != 'E')
                        return -EINVAL;
 
                if (_IOC_DIR(cmd) == _IOC_READ) {
 
                        if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) {
 
                                unsigned long *bits;
                                int len;
 
                                switch (_IOC_NR(cmd) & EV_MAX) {
 
                                case      0: bits = dev->evbit;  len = EV_MAX;  break;
                                case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
                                case EV_REL: bits = dev->relbit; len = REL_MAX; break;
                                case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
                                case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
                                case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
                                case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
                                case EV_FF:  bits = dev->ffbit;  len = FF_MAX;  break;
                                case EV_SW:  bits = dev->swbit;  len = SW_MAX;  break;
                                default: return -EINVAL;
                        }
                                return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
                        }
 
                        if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
                                return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
                                                    p, compat_mode);
 
                        if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
                                return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
                                                    p, compat_mode);
 
                        if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
                                return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
                                                    p, compat_mode);
 
                        if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
                                return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
                                                    p, compat_mode);
 
                        if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
                                return str_to_user(dev->name, _IOC_SIZE(cmd), p);
 
                        if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
                                return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
 
                        if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
                                return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
 
                        if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
 
                                t = _IOC_NR(cmd) & ABS_MAX;
 
                                abs.value = dev->abs[t];
                                abs.minimum = dev->absmin[t];
                                abs.maximum = dev->absmax[t];
                                abs.fuzz = dev->absfuzz[t];
                                abs.flat = dev->absflat[t];
 
                                if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
                                        return -EFAULT;
 
                                return 0;
                        }
 
                }
 
                if (_IOC_DIR(cmd) == _IOC_WRITE) {
 
                        if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
 
                                t = _IOC_NR(cmd) & ABS_MAX;
 
                                if (copy_from_user(&abs, p,
                                                sizeof(struct input_absinfo)))
                                        return -EFAULT;
 
                                /*
                                 * Take event lock to ensure that we are not
                                 * changing device parameters in the middle
                                 * of event.
                                 */
                                spin_lock_irq(&dev->event_lock);
 
                                dev->abs[t] = abs.value;
                                dev->absmin[t] = abs.minimum;
                                dev->absmax[t] = abs.maximum;
                                dev->absfuzz[t] = abs.fuzz;
                                dev->absflat[t] = abs.flat;
 
                                spin_unlock_irq(&dev->event_lock);
 
                                return 0;
                        }
                }
        }
        return -EINVAL;
}
 
static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
                                void __user *p, int compat_mode)
{
        struct evdev_client *client = file->private_data;
        struct evdev *evdev = client->evdev;
        int retval;
 
        retval = mutex_lock_interruptible(&evdev->mutex);
        if (retval)
                return retval;
 
        if (!evdev->exist) {
                retval = -ENODEV;
                goto out;
        }
 
        retval = evdev_do_ioctl(file, cmd, p, compat_mode);
 
 out:
        mutex_unlock(&evdev->mutex);
        return retval;
}
 
static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
        return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
}
 
#ifdef CONFIG_COMPAT
static long evdev_ioctl_compat(struct file *file,
                                unsigned int cmd, unsigned long arg)
{
        return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
}
#endif
 
static const struct file_operations evdev_fops = {
        .owner          = THIS_MODULE,
        .read           = evdev_read,
        .write          = evdev_write,
        .poll           = evdev_poll,
        .open           = evdev_open,
        .release        = evdev_release,
        .unlocked_ioctl = evdev_ioctl,
#ifdef CONFIG_COMPAT
        .compat_ioctl   = evdev_ioctl_compat,
#endif
        .fasync         = evdev_fasync,
        .flush          = evdev_flush
};
 
static int evdev_install_chrdev(struct evdev *evdev)
{
        /*
         * No need to do any locking here as calls to connect and
         * disconnect are serialized by the input core
         */
        evdev_table[evdev->minor] = evdev;
        return 0;
}
 
static void evdev_remove_chrdev(struct evdev *evdev)
{
        /*
         * Lock evdev table to prevent race with evdev_open()
         */
        mutex_lock(&evdev_table_mutex);
        evdev_table[evdev->minor] = NULL;
        mutex_unlock(&evdev_table_mutex);
}
 
/*
 * 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 evdev_mark_dead(struct evdev *evdev)
{
        mutex_lock(&evdev->mutex);
        evdev->exist = 0;
        mutex_unlock(&evdev->mutex);
}
 
static void evdev_cleanup(struct evdev *evdev)
{
        struct input_handle *handle = &evdev->handle;
 
        evdev_mark_dead(evdev);
        evdev_hangup(evdev);
        evdev_remove_chrdev(evdev);
 
        /* evdev is marked dead so no one else accesses evdev->open */
        if (evdev->open) {
                input_flush_device(handle, NULL);
                input_close_device(handle);
        }
}
 
/*
 * Create new evdev device. Note that input core serializes calls
 * to connect and disconnect so we don't need to lock evdev_table here.
 */
static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
                         const struct input_device_id *id)
{
        struct evdev *evdev;
        int minor;
        int error;
 
        for (minor = 0; minor < EVDEV_MINORS; minor++)
                if (!evdev_table[minor])
                        break;
 
        if (minor == EVDEV_MINORS) {
                printk(KERN_ERR "evdev: no more free evdev devices\n");
                return -ENFILE;
        }
 
        evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
        if (!evdev)
                return -ENOMEM;
 
        INIT_LIST_HEAD(&evdev->client_list);
        spin_lock_init(&evdev->client_lock);
        mutex_init(&evdev->mutex);
        init_waitqueue_head(&evdev->wait);
 
        snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
        evdev->exist = 1;
        evdev->minor = minor;
 
        evdev->handle.dev = dev;
        evdev->handle.name = evdev->name;
        evdev->handle.handler = handler;
        evdev->handle.private = evdev;
 
        strlcpy(evdev->dev.bus_id, evdev->name, sizeof(evdev->dev.bus_id));
        evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
        evdev->dev.class = &input_class;
        evdev->dev.parent = &dev->dev;
        evdev->dev.release = evdev_free;
        device_initialize(&evdev->dev);
 
        error = input_register_handle(&evdev->handle);
        if (error)
                goto err_free_evdev;
 
        error = evdev_install_chrdev(evdev);
        if (error)
                goto err_unregister_handle;
 
        error = device_add(&evdev->dev);
        if (error)
                goto err_cleanup_evdev;
 
        return 0;
 
 err_cleanup_evdev:
        evdev_cleanup(evdev);
 err_unregister_handle:
        input_unregister_handle(&evdev->handle);
 err_free_evdev:
        put_device(&evdev->dev);
        return error;
}
 
static void evdev_disconnect(struct input_handle *handle)
{
        struct evdev *evdev = handle->private;
 
        device_del(&evdev->dev);
        evdev_cleanup(evdev);
        input_unregister_handle(handle);
        put_device(&evdev->dev);
}
 
static const struct input_device_id evdev_ids[] = {
        { .driver_info = 1 },   /* Matches all devices */
        { },                    /* Terminating zero entry */
};
 
MODULE_DEVICE_TABLE(input, evdev_ids);
 
static struct input_handler evdev_handler = {
        .event          = evdev_event,
        .connect        = evdev_connect,
        .disconnect     = evdev_disconnect,
        .fops           = &evdev_fops,
        .minor          = EVDEV_MINOR_BASE,
        .name           = "evdev",
        .id_table       = evdev_ids,
};
 
static int __init evdev_init(void)
{
        return input_register_handler(&evdev_handler);
}
 
static void __exit evdev_exit(void)
{
        input_unregister_handler(&evdev_handler);
}
 
module_init(evdev_init);
module_exit(evdev_exit);
 
MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Input driver event char devices");
MODULE_LICENSE("GPL");
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[/] [test_project/] [trunk/] [linux_sd_driver/] [drivers/] [input/] [evdev.c] - Blame information for rev 62

Line No.	Rev	Author	Line
1	62	marcus.erl	`/*`
2			`* Event char devices, giving access to raw input device events.`
3			`*`
4			`* Copyright (c) 1999-2002 Vojtech Pavlik`
5			`*`
6			`* This program is free software; you can redistribute it and/or modify it`
7			`* under the terms of the GNU General Public License version 2 as published by`
8			`* the Free Software Foundation.`
9			`*/`
10
11			`#define EVDEV_MINOR_BASE 64`
12			`#define EVDEV_MINORS 32`
13			`#define EVDEV_BUFFER_SIZE 64`
14
15			`#include <linux/poll.h>`
16			`#include <linux/slab.h>`
17			`#include <linux/module.h>`
18			`#include <linux/init.h>`
19			`#include <linux/input.h>`
20			`#include <linux/major.h>`
21			`#include <linux/device.h>`
22			`#include <linux/compat.h>`
23
24			`struct evdev {`
25			`int exist;`
26			`int open;`
27			`int minor;`
28			`char name[16];`
29			`struct input_handle handle;`
30			`wait_queue_head_t wait;`
31			`struct evdev_client *grab;`
32			`struct list_head client_list;`
33			`spinlock_t client_lock; /* protects client_list */`
34			`struct mutex mutex;`
35			`struct device dev;`
36			`};`
37
38			`struct evdev_client {`
39			`struct input_event buffer[EVDEV_BUFFER_SIZE];`
40			`int head;`