1 files changed, 395 insertions, 0 deletions

diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
new file mode 100644
index 000000000000..20ebba1032b8
--- /dev/null
+++ b/drivers/hid/hidraw.c
@@ -0,0 +1,395 @@
+/*
+ * 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 (copy_to_user(*((__u8 **)(user_arg +
+                                                        sizeof(__u32))),
+                                                        dev->hid->rdesc, 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 = -EINVAL;
+        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
+         */
+
+        if (!(dev = kzalloc(sizeof(struct hidraw), GFP_KERNEL)))
+                return -1;
+
+        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)
+                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);
+                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);
+
+}