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Diffstat (limited to 'drivers/hid/hidraw.c')
-rw-r--r--drivers/hid/hidraw.c407
1 files changed, 407 insertions, 0 deletions
diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
new file mode 100644
index 00000000000..a702e2f6da7
--- /dev/null
+++ b/drivers/hid/hidraw.c
@@ -0,0 +1,407 @@
+/*
+ * HID raw devices, giving access to raw HID events.
+ *
+ * In comparison to hiddev, this device does not process the
+ * hid events at all (no parsing, no lookups). This lets applications
+ * to work on raw hid events as they want to, and avoids a need to
+ * use a transport-specific userspace libhid/libusb libraries.
+ *
+ * Copyright (c) 2007 Jiri Kosina
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/cdev.h>
+#include <linux/poll.h>
+#include <linux/device.h>
+#include <linux/major.h>
+#include <linux/hid.h>
+#include <linux/mutex.h>
+
+#include <linux/hidraw.h>
+
+static int hidraw_major;
+static struct cdev hidraw_cdev;
+static struct class *hidraw_class;
+static struct hidraw *hidraw_table[HIDRAW_MAX_DEVICES];
+static DEFINE_SPINLOCK(minors_lock);
+
+static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
+{
+ struct hidraw_list *list = file->private_data;
+ int ret = 0, len;
+ char *report;
+ DECLARE_WAITQUEUE(wait, current);
+
+ while (ret == 0) {
+
+ mutex_lock(&list->read_mutex);
+
+ if (list->head == list->tail) {
+ add_wait_queue(&list->hidraw->wait, &wait);
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ while (list->head == list->tail) {
+ if (file->f_flags & O_NONBLOCK) {
+ ret = -EAGAIN;
+ break;
+ }
+ if (signal_pending(current)) {
+ ret = -ERESTARTSYS;
+ break;
+ }
+ if (!list->hidraw->exist) {
+ ret = -EIO;
+ break;
+ }
+
+ /* allow O_NONBLOCK to work well from other threads */
+ mutex_unlock(&list->read_mutex);
+ schedule();
+ mutex_lock(&list->read_mutex);
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&list->hidraw->wait, &wait);
+ }
+
+ if (ret)
+ goto out;
+
+ report = list->buffer[list->tail].value;
+ len = list->buffer[list->tail].len > count ?
+ count : list->buffer[list->tail].len;
+
+ if (copy_to_user(buffer, list->buffer[list->tail].value, len)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ ret += len;
+
+ kfree(list->buffer[list->tail].value);
+ list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
+ }
+out:
+ mutex_unlock(&list->read_mutex);
+ return ret;
+}
+
+/* the first byte is expected to be a report number */
+static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
+{
+ unsigned int minor = iminor(file->f_path.dentry->d_inode);
+ struct hid_device *dev = hidraw_table[minor]->hid;
+ __u8 *buf;
+ int ret = 0;
+
+ if (!dev->hid_output_raw_report)
+ return -ENODEV;
+
+ if (count > HID_MIN_BUFFER_SIZE) {
+ printk(KERN_WARNING "hidraw: pid %d passed too large report\n",
+ current->pid);
+ return -EINVAL;
+ }
+
+ if (count < 2) {
+ printk(KERN_WARNING "hidraw: pid %d passed too short report\n",
+ current->pid);
+ return -EINVAL;
+ }
+
+ buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ if (copy_from_user(buf, buffer, count)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ ret = dev->hid_output_raw_report(dev, buf, count);
+out:
+ kfree(buf);
+ return ret;
+}
+
+static unsigned int hidraw_poll(struct file *file, poll_table *wait)
+{
+ struct hidraw_list *list = file->private_data;
+
+ poll_wait(file, &list->hidraw->wait, wait);
+ if (list->head != list->tail)
+ return POLLIN | POLLRDNORM;
+ if (!list->hidraw->exist)
+ return POLLERR | POLLHUP;
+ return 0;
+}
+
+static int hidraw_open(struct inode *inode, struct file *file)
+{
+ unsigned int minor = iminor(inode);
+ struct hidraw *dev;
+ struct hidraw_list *list;
+ int err = 0;
+
+ if (!(list = kzalloc(sizeof(struct hidraw_list), GFP_KERNEL))) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ spin_lock(&minors_lock);
+ if (!hidraw_table[minor]) {
+ printk(KERN_EMERG "hidraw device with minor %d doesn't exist\n",
+ minor);
+ kfree(list);
+ err = -ENODEV;
+ goto out_unlock;
+ }
+
+ list->hidraw = hidraw_table[minor];
+ mutex_init(&list->read_mutex);
+ list_add_tail(&list->node, &hidraw_table[minor]->list);
+ file->private_data = list;
+
+ dev = hidraw_table[minor];
+ if (!dev->open++)
+ dev->hid->hid_open(dev->hid);
+
+out_unlock:
+ spin_unlock(&minors_lock);
+out:
+ return err;
+
+}
+
+static int hidraw_release(struct inode * inode, struct file * file)
+{
+ unsigned int minor = iminor(inode);
+ struct hidraw *dev;
+ struct hidraw_list *list = file->private_data;
+
+ if (!hidraw_table[minor]) {
+ printk(KERN_EMERG "hidraw device with minor %d doesn't exist\n",
+ minor);
+ return -ENODEV;
+ }
+
+ list_del(&list->node);
+ dev = hidraw_table[minor];
+ if (!dev->open--) {
+ if (list->hidraw->exist)
+ dev->hid->hid_close(dev->hid);
+ else
+ kfree(list->hidraw);
+ }
+
+ return 0;
+}
+
+static int hidraw_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+ unsigned int minor = iminor(inode);
+ struct hidraw *dev = hidraw_table[minor];
+ void __user *user_arg = (void __user*) arg;
+
+ switch (cmd) {
+ case HIDIOCGRDESCSIZE:
+ if (put_user(dev->hid->rsize, (int __user *)arg))
+ return -EFAULT;
+ return 0;
+
+ case HIDIOCGRDESC:
+ {
+ __u32 len;
+
+ if (get_user(len, (int __user *)arg))
+ return -EFAULT;
+
+ if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
+ return -EINVAL;
+
+ if (copy_to_user(user_arg + offsetof(
+ struct hidraw_report_descriptor,
+ value[0]),
+ dev->hid->rdesc,
+ min(dev->hid->rsize, len)))
+ return -EFAULT;
+ return 0;
+ }
+ case HIDIOCGRAWINFO:
+ {
+ struct hidraw_devinfo dinfo;
+
+ dinfo.bustype = dev->hid->bus;
+ dinfo.vendor = dev->hid->vendor;
+ dinfo.product = dev->hid->product;
+ if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
+ return -EFAULT;
+
+ return 0;
+ }
+ default:
+ printk(KERN_EMERG "hidraw: unsupported ioctl() %x\n",
+ cmd);
+ }
+ return -EINVAL;
+}
+
+static const struct file_operations hidraw_ops = {
+ .owner = THIS_MODULE,
+ .read = hidraw_read,
+ .write = hidraw_write,
+ .poll = hidraw_poll,
+ .open = hidraw_open,
+ .release = hidraw_release,
+ .ioctl = hidraw_ioctl,
+};
+
+void hidraw_report_event(struct hid_device *hid, u8 *data, int len)
+{
+ struct hidraw *dev = hid->hidraw;
+ struct hidraw_list *list;
+
+ list_for_each_entry(list, &dev->list, node) {
+ list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC);
+ list->buffer[list->head].len = len;
+ list->head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
+ kill_fasync(&list->fasync, SIGIO, POLL_IN);
+ }
+
+ wake_up_interruptible(&dev->wait);
+}
+EXPORT_SYMBOL_GPL(hidraw_report_event);
+
+int hidraw_connect(struct hid_device *hid)
+{
+ int minor, result;
+ struct hidraw *dev;
+
+ /* TODO currently we accept any HID device. This should later
+ * probably be fixed to accept only those devices which provide
+ * non-input applications
+ */
+
+ dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
+
+ result = -EINVAL;
+
+ spin_lock(&minors_lock);
+
+ for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
+ if (hidraw_table[minor])
+ continue;
+ hidraw_table[minor] = dev;
+ result = 0;
+ break;
+ }
+
+ spin_unlock(&minors_lock);
+
+ if (result) {
+ kfree(dev);
+ goto out;
+ }
+
+ dev->dev = device_create(hidraw_class, NULL, MKDEV(hidraw_major, minor),
+ "%s%d", "hidraw", minor);
+
+ if (IS_ERR(dev->dev)) {
+ spin_lock(&minors_lock);
+ hidraw_table[minor] = NULL;
+ spin_unlock(&minors_lock);
+ result = PTR_ERR(dev->dev);
+ kfree(dev);
+ goto out;
+ }
+
+ init_waitqueue_head(&dev->wait);
+ INIT_LIST_HEAD(&dev->list);
+
+ dev->hid = hid;
+ dev->minor = minor;
+
+ dev->exist = 1;
+ hid->hidraw = dev;
+
+out:
+ return result;
+
+}
+EXPORT_SYMBOL_GPL(hidraw_connect);
+
+void hidraw_disconnect(struct hid_device *hid)
+{
+ struct hidraw *hidraw = hid->hidraw;
+
+ hidraw->exist = 0;
+
+ spin_lock(&minors_lock);
+ hidraw_table[hidraw->minor] = NULL;
+ spin_unlock(&minors_lock);
+
+ device_destroy(hidraw_class, MKDEV(hidraw_major, hidraw->minor));
+
+ if (hidraw->open) {
+ hid->hid_close(hid);
+ wake_up_interruptible(&hidraw->wait);
+ } else {
+ kfree(hidraw);
+ }
+}
+EXPORT_SYMBOL_GPL(hidraw_disconnect);
+
+int __init hidraw_init(void)
+{
+ int result;
+ dev_t dev_id;
+
+ result = alloc_chrdev_region(&dev_id, HIDRAW_FIRST_MINOR,
+ HIDRAW_MAX_DEVICES, "hidraw");
+
+ hidraw_major = MAJOR(dev_id);
+
+ if (result < 0) {
+ printk(KERN_WARNING "hidraw: can't get major number\n");
+ result = 0;
+ goto out;
+ }
+
+ hidraw_class = class_create(THIS_MODULE, "hidraw");
+ if (IS_ERR(hidraw_class)) {
+ result = PTR_ERR(hidraw_class);
+ unregister_chrdev(hidraw_major, "hidraw");
+ goto out;
+ }
+
+ cdev_init(&hidraw_cdev, &hidraw_ops);
+ cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
+out:
+ return result;
+}
+
+void __exit hidraw_exit(void)
+{
+ dev_t dev_id = MKDEV(hidraw_major, 0);
+
+ cdev_del(&hidraw_cdev);
+ class_destroy(hidraw_class);
+ unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
+
+}
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