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-rw-r--r--drivers/input/evdev.c1075
1 files changed, 1075 insertions, 0 deletions
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
new file mode 100644
index 0000000..1070db3
--- /dev/null
+++ b/drivers/input/evdev.c
@@ -0,0 +1,1075 @@
+/*
+ * 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);
+
+ input_put_device(evdev->handle.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_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;
+};
+
+struct ff_periodic_effect_compat {
+ __u16 waveform;
+ __u16 period;
+ __s16 magnitude;
+ __s16 offset;
+ __u16 phase;
+
+ struct ff_envelope envelope;
+
+ __u32 custom_len;
+ compat_uptr_t custom_data;
+};
+
+struct ff_effect_compat {
+ __u16 type;
+ __s16 id;
+ __u16 direction;
+ struct ff_trigger trigger;
+ struct ff_replay replay;
+
+ union {
+ struct ff_constant_effect constant;
+ struct ff_ramp_effect ramp;
+ struct ff_periodic_effect_compat periodic;
+ struct ff_condition_effect condition[2]; /* One for each axis */
+ struct ff_rumble_effect rumble;
+ } u;
+};
+
+/* 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;
+}
+
+static int evdev_ff_effect_from_user(const char __user *buffer, size_t size,
+ struct ff_effect *effect)
+{
+ if (COMPAT_TEST) {
+ struct ff_effect_compat *compat_effect;
+
+ if (size != sizeof(struct ff_effect_compat))
+ return -EINVAL;
+
+ /*
+ * It so happens that the pointer which needs to be changed
+ * is the last field in the structure, so we can copy the
+ * whole thing and replace just the pointer.
+ */
+
+ compat_effect = (struct ff_effect_compat *)effect;
+
+ if (copy_from_user(compat_effect, buffer,
+ sizeof(struct ff_effect_compat)))
+ return -EFAULT;
+
+ if (compat_effect->type == FF_PERIODIC &&
+ compat_effect->u.periodic.waveform == FF_CUSTOM)
+ effect->u.periodic.custom_data =
+ compat_ptr(compat_effect->u.periodic.custom_data);
+ } else {
+ if (size != sizeof(struct ff_effect))
+ return -EINVAL;
+
+ if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
+ 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;
+}
+
+static int evdev_ff_effect_from_user(const char __user *buffer, size_t size,
+ struct ff_effect *effect)
+{
+ if (size != sizeof(struct ff_effect))
+ return -EINVAL;
+
+ if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
+ 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;
+}
+
+#define OLD_KEY_MAX 0x1ff
+static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode)
+{
+ static unsigned long keymax_warn_time;
+ 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;
+ }
+
+ /*
+ * Work around bugs in userspace programs that like to do
+ * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
+ * should be in bytes, not in bits.
+ */
+ if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) {
+ len = OLD_KEY_MAX;
+ if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
+ printk(KERN_WARNING
+ "evdev.c(EVIOCGBIT): Suspicious buffer size %u, "
+ "limiting output to %zu bytes. See "
+ "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
+ OLD_KEY_MAX,
+ BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
+ }
+
+ return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
+}
+#undef OLD_KEY_MAX
+
+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 = input_get_keycode(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 input_set_keycode(dev, t, v);
+
+ 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)))
+ return handle_eviocgbit(dev, 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) == _IOC_NR(EVIOCSFF)) {
+
+ if (evdev_ff_effect_from_user(p, _IOC_SIZE(cmd), &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;
+ }
+
+ 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 = input_get_device(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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