// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  USB HID support for Linux
 *
 *  Copyright (c) 1999 Andreas Gal
 *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
 *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
 *  Copyright (c) 2007-2008 Oliver Neukum
 *  Copyright (c) 2006-2010 Jiri Kosina
 */

/*
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/property.h>
#include <linux/spinlock.h>
#include <linux/unaligned.h>
#include <asm/byteorder.h>
#include <linux/input.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
#include <linux/string.h>

#include <linux/usb.h>

#include <linux/hid.h>
#include <linux/hiddev.h>
#include <linux/hid-debug.h>
#include <linux/hidraw.h>
#include "usbhid.h"
#include "hid-pidff.h"

/*
 * Version Information
 */

#define DRIVER_DESC "USB HID core driver"

/*
 * Module parameters.
 */

static unsigned int hid_mousepoll_interval;
module_param_named(mousepoll, hid_mousepoll_interval, uint, 0644);
MODULE_PARM_DESC(mousepoll, "Polling interval of mice");

static unsigned int hid_jspoll_interval;
module_param_named(jspoll, hid_jspoll_interval, uint, 0644);
MODULE_PARM_DESC(jspoll, "Polling interval of joysticks");

static unsigned int hid_kbpoll_interval;
module_param_named(kbpoll, hid_kbpoll_interval, uint, 0644);
MODULE_PARM_DESC(kbpoll, "Polling interval of keyboards");

static unsigned int ignoreled;
module_param_named(ignoreled, ignoreled, uint, 0644);
MODULE_PARM_DESC(ignoreled, "Autosuspend with active leds");

/* Quirks specified at module load time */
static char *quirks_param[MAX_USBHID_BOOT_QUIRKS];
module_param_array_named(quirks, quirks_param, charp, NULL, 0444);
MODULE_PARM_DESC(quirks, "Add/modify USB HID quirks by specifying "
                " quirks=vendorID:productID:quirks"
                " where vendorID, productID, and quirks are all in"
                " 0x-prefixed hex");
/*
 * Input submission and I/O error handler.
 */
static void hid_io_error(struct hid_device *hid);
static int hid_submit_out(struct hid_device *hid);
static int hid_submit_ctrl(struct hid_device *hid);
static void hid_cancel_delayed_stuff(struct usbhid_device *usbhid);

/* Start up the input URB */
static int hid_start_in(struct hid_device *hid)
{
        unsigned long flags;
        int rc = 0;
        struct usbhid_device *usbhid = hid->driver_data;

        spin_lock_irqsave(&usbhid->lock, flags);
        if (test_bit(HID_IN_POLLING, &usbhid->iofl) &&
            !test_bit(HID_DISCONNECTED, &usbhid->iofl) &&
            !test_bit(HID_SUSPENDED, &usbhid->iofl) &&
            !test_and_set_bit(HID_IN_RUNNING, &usbhid->iofl)) {
                rc = usb_submit_urb(usbhid->urbin, GFP_ATOMIC);
                if (rc != 0) {
                        clear_bit(HID_IN_RUNNING, &usbhid->iofl);
                        if (rc == -ENOSPC)
                                set_bit(HID_NO_BANDWIDTH, &usbhid->iofl);
                } else {
                        clear_bit(HID_NO_BANDWIDTH, &usbhid->iofl);
                }
        }
        spin_unlock_irqrestore(&usbhid->lock, flags);
        return rc;
}

/* I/O retry timer routine */
static void hid_retry_timeout(struct timer_list *t)
{
        struct usbhid_device *usbhid = timer_container_of(usbhid, t, io_retry);
        struct hid_device *hid = usbhid->hid;

        dev_dbg(&usbhid->intf->dev, "retrying intr urb\n");
        if (hid_start_in(hid))
                hid_io_error(hid);
}

/* Workqueue routine to reset the device or clear a halt */
static void hid_reset(struct work_struct *work)
{
        struct usbhid_device *usbhid =
                container_of(work, struct usbhid_device, reset_work);
        struct hid_device *hid = usbhid->hid;
        int rc;

        if (test_bit(HID_CLEAR_HALT, &usbhid->iofl)) {
                dev_dbg(&usbhid->intf->dev, "clear halt\n");
                rc = usb_clear_halt(hid_to_usb_dev(hid), usbhid->urbin->pipe);
                clear_bit(HID_CLEAR_HALT, &usbhid->iofl);
                if (rc == 0) {
                        hid_start_in(hid);
                } else {
                        dev_dbg(&usbhid->intf->dev,
                                        "clear-halt failed: %d\n", rc);
                        set_bit(HID_RESET_PENDING, &usbhid->iofl);
                }
        }

        if (test_bit(HID_RESET_PENDING, &usbhid->iofl)) {
                dev_dbg(&usbhid->intf->dev, "resetting device\n");
                usb_queue_reset_device(usbhid->intf);
        }
}

/* Main I/O error handler */
static void hid_io_error(struct hid_device *hid)
{
        unsigned long flags;
        struct usbhid_device *usbhid = hid->driver_data;

        spin_lock_irqsave(&usbhid->lock, flags);

        /* Stop when disconnected */
        if (test_bit(HID_DISCONNECTED, &usbhid->iofl))
                goto done;

        /* If it has been a while since the last error, we'll assume
         * this a brand new error and reset the retry timeout. */
        if (time_after(jiffies, usbhid->stop_retry + HZ/2))
                usbhid->retry_delay = 0;

        /* When an error occurs, retry at increasing intervals */
        if (usbhid->retry_delay == 0) {
                usbhid->retry_delay = 13;       /* Then 26, 52, 104, 104, ... */
                usbhid->stop_retry = jiffies + msecs_to_jiffies(1000);
        } else if (usbhid->retry_delay < 100)
                usbhid->retry_delay *= 2;

        if (time_after(jiffies, usbhid->stop_retry)) {

                /* Retries failed, so do a port reset unless we lack bandwidth*/
                if (!test_bit(HID_NO_BANDWIDTH, &usbhid->iofl)
                     && !test_and_set_bit(HID_RESET_PENDING, &usbhid->iofl)) {

                        schedule_work(&usbhid->reset_work);
                        goto done;
                }
        }

        mod_timer(&usbhid->io_retry,
                        jiffies + msecs_to_jiffies(usbhid->retry_delay));
done:
        spin_unlock_irqrestore(&usbhid->lock, flags);
}

static void usbhid_mark_busy(struct usbhid_device *usbhid)
{
        struct usb_interface *intf = usbhid->intf;

        usb_mark_last_busy(interface_to_usbdev(intf));
}

static int usbhid_restart_out_queue(struct usbhid_device *usbhid)
{
        struct hid_device *hid = usb_get_intfdata(usbhid->intf);
        int kicked;
        int r;

        if (!hid || test_bit(HID_RESET_PENDING, &usbhid->iofl) ||
                        test_bit(HID_SUSPENDED, &usbhid->iofl))
                return 0;

        if ((kicked = (usbhid->outhead != usbhid->outtail))) {
                hid_dbg(hid, "Kicking head %d tail %d", usbhid->outhead, usbhid->outtail);

                /* Try to wake up from autosuspend... */
                r = usb_autopm_get_interface_async(usbhid->intf);
                if (r < 0)
                        return r;

                /*
                 * If still suspended, don't submit.  Submission will
                 * occur if/when resume drains the queue.
                 */
                if (test_bit(HID_SUSPENDED, &usbhid->iofl)) {
                        usb_autopm_put_interface_no_suspend(usbhid->intf);
                        return r;
                }

                /* Asynchronously flush queue. */
                set_bit(HID_OUT_RUNNING, &usbhid->iofl);
                if (hid_submit_out(hid)) {
                        clear_bit(HID_OUT_RUNNING, &usbhid->iofl);
                        usb_autopm_put_interface_async(usbhid->intf);
                }
                wake_up(&usbhid->wait);
        }
        return kicked;
}

static int usbhid_restart_ctrl_queue(struct usbhid_device *usbhid)
{
        struct hid_device *hid = usb_get_intfdata(usbhid->intf);
        int kicked;
        int r;

        WARN_ON(hid == NULL);
        if (!hid || test_bit(HID_RESET_PENDING, &usbhid->iofl) ||
                        test_bit(HID_SUSPENDED, &usbhid->iofl))
                return 0;

        if ((kicked = (usbhid->ctrlhead != usbhid->ctrltail))) {
                hid_dbg(hid, "Kicking head %d tail %d", usbhid->ctrlhead, usbhid->ctrltail);

                /* Try to wake up from autosuspend... */
                r = usb_autopm_get_interface_async(usbhid->intf);
                if (r < 0)
                        return r;

                /*
                 * If still suspended, don't submit.  Submission will
                 * occur if/when resume drains the queue.
                 */
                if (test_bit(HID_SUSPENDED, &usbhid->iofl)) {
                        usb_autopm_put_interface_no_suspend(usbhid->intf);
                        return r;
                }

                /* Asynchronously flush queue. */
                set_bit(HID_CTRL_RUNNING, &usbhid->iofl);
                if (hid_submit_ctrl(hid)) {
                        clear_bit(HID_CTRL_RUNNING, &usbhid->iofl);
                        usb_autopm_put_interface_async(usbhid->intf);
                }
                wake_up(&usbhid->wait);
        }
        return kicked;
}

/*
 * Input interrupt completion handler.
 */

static void hid_irq_in(struct urb *urb)
{
        struct hid_device       *hid = urb->context;
        struct usbhid_device    *usbhid = hid->driver_data;
        int                     status;

        switch (urb->status) {
        case 0:                 /* success */
                usbhid->retry_delay = 0;
                if (!test_bit(HID_OPENED, &usbhid->iofl))
                        break;
                usbhid_mark_busy(usbhid);
                if (!test_bit(HID_RESUME_RUNNING, &usbhid->iofl)) {
                        hid_input_report(urb->context, HID_INPUT_REPORT,
                                         urb->transfer_buffer,
                                         urb->actual_length, 1);
                        /*
                         * autosuspend refused while keys are pressed
                         * because most keyboards don't wake up when
                         * a key is released
                         */
                        if (hid_check_keys_pressed(hid))
                                set_bit(HID_KEYS_PRESSED, &usbhid->iofl);
                        else
                                clear_bit(HID_KEYS_PRESSED, &usbhid->iofl);
                }
                break;
        case -EPIPE:            /* stall */
                usbhid_mark_busy(usbhid);
                clear_bit(HID_IN_RUNNING, &usbhid->iofl);
                set_bit(HID_CLEAR_HALT, &usbhid->iofl);
                schedule_work(&usbhid->reset_work);
                return;
        case -ECONNRESET:       /* unlink */
        case -ENOENT:
        case -ESHUTDOWN:        /* unplug */
                clear_bit(HID_IN_RUNNING, &usbhid->iofl);
                return;
        case -EILSEQ:           /* protocol error or unplug */
        case -EPROTO:           /* protocol error or unplug */
        case -ETIME:            /* protocol error or unplug */
        case -ETIMEDOUT:        /* Should never happen, but... */
                usbhid_mark_busy(usbhid);
                clear_bit(HID_IN_RUNNING, &usbhid->iofl);
                hid_io_error(hid);
                return;
        default:                /* error */
                hid_warn(urb->dev, "input irq status %d received\n",
                         urb->status);
        }

        status = usb_submit_urb(urb, GFP_ATOMIC);
        if (status) {
                clear_bit(HID_IN_RUNNING, &usbhid->iofl);
                if (status != -EPERM) {
                        hid_err(hid, "can't resubmit intr, %s-%s/input%d, status %d\n",
                                hid_to_usb_dev(hid)->bus->bus_name,
                                hid_to_usb_dev(hid)->devpath,
                                usbhid->ifnum, status);
                        hid_io_error(hid);
                }
        }
}

static int hid_submit_out(struct hid_device *hid)
{
        struct hid_report *report;
        char *raw_report;
        struct usbhid_device *usbhid = hid->driver_data;
        int r;

        report = usbhid->out[usbhid->outtail].report;
        raw_report = usbhid->out[usbhid->outtail].raw_report;

        usbhid->urbout->transfer_buffer_length = hid_report_len(report);
        usbhid->urbout->dev = hid_to_usb_dev(hid);
        if (raw_report) {
                memcpy(usbhid->outbuf, raw_report,
                                usbhid->urbout->transfer_buffer_length);
                kfree(raw_report);
                usbhid->out[usbhid->outtail].raw_report = NULL;
        }

        dbg_hid("submitting out urb\n");

        r = usb_submit_urb(usbhid->urbout, GFP_ATOMIC);
        if (r < 0) {
                hid_err(hid, "usb_submit_urb(out) failed: %d\n", r);
                return r;
        }
        usbhid->last_out = jiffies;
        return 0;
}

static int hid_submit_ctrl(struct hid_device *hid)
{
        struct hid_report *report;
        unsigned char dir;
        char *raw_report;
        int len, r;
        struct usbhid_device *usbhid = hid->driver_data;

        report = usbhid->ctrl[usbhid->ctrltail].report;
        raw_report = usbhid->ctrl[usbhid->ctrltail].raw_report;
        dir = usbhid->ctrl[usbhid->ctrltail].dir;

        len = hid_report_len(report);
        if (dir == USB_DIR_OUT) {
                usbhid->urbctrl->pipe = usb_sndctrlpipe(hid_to_usb_dev(hid), 0);
                if (raw_report) {
                        memcpy(usbhid->ctrlbuf, raw_report, len);
                        kfree(raw_report);
                        usbhid->ctrl[usbhid->ctrltail].raw_report = NULL;
                }
        } else {
                int maxpacket;

                usbhid->urbctrl->pipe = usb_rcvctrlpipe(hid_to_usb_dev(hid), 0);
                maxpacket = usb_maxpacket(hid_to_usb_dev(hid),
                                          usbhid->urbctrl->pipe);
                len += (len == 0);      /* Don't allow 0-length reports */
                len = round_up(len, maxpacket);
                if (len > usbhid->bufsize)
                        len = usbhid->bufsize;
        }
        usbhid->urbctrl->transfer_buffer_length = len;
        usbhid->urbctrl->dev = hid_to_usb_dev(hid);

        usbhid->cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE | dir;
        usbhid->cr->bRequest = (dir == USB_DIR_OUT) ? HID_REQ_SET_REPORT :
                                                      HID_REQ_GET_REPORT;
        usbhid->cr->wValue = cpu_to_le16(((report->type + 1) << 8) |
                                         report->id);
        usbhid->cr->wIndex = cpu_to_le16(usbhid->ifnum);
        usbhid->cr->wLength = cpu_to_le16(len);

        dbg_hid("submitting ctrl urb: %s wValue=0x%04x wIndex=0x%04x wLength=%u\n",
                usbhid->cr->bRequest == HID_REQ_SET_REPORT ? "Set_Report" :
                                                             "Get_Report",
                usbhid->cr->wValue, usbhid->cr->wIndex, usbhid->cr->wLength);

        r = usb_submit_urb(usbhid->urbctrl, GFP_ATOMIC);
        if (r < 0) {
                hid_err(hid, "usb_submit_urb(ctrl) failed: %d\n", r);
                return r;
        }
        usbhid->last_ctrl = jiffies;
        return 0;
}

/*
 * Output interrupt completion handler.
 */

static void hid_irq_out(struct urb *urb)
{
        struct hid_device *hid = urb->context;
        struct usbhid_device *usbhid = hid->driver_data;
        unsigned long flags;
        int unplug = 0;

        switch (urb->status) {
        case 0:                 /* success */
                break;
        case -ESHUTDOWN:        /* unplug */
                unplug = 1;
                break;
        case -EILSEQ:           /* protocol error or unplug */
        case -EPROTO:           /* protocol error or unplug */
        case -ECONNRESET:       /* unlink */
        case -ENOENT:
                break;
        default:                /* error */
                hid_warn(urb->dev, "output irq status %d received\n",
                         urb->status);
        }

        spin_lock_irqsave(&usbhid->lock, flags);

        if (unplug) {
                usbhid->outtail = usbhid->outhead;
        } else {
                usbhid->outtail = (usbhid->outtail + 1) & (HID_OUTPUT_FIFO_SIZE - 1);

                if (usbhid->outhead != usbhid->outtail &&
                                hid_submit_out(hid) == 0) {
                        /* Successfully submitted next urb in queue */
                        spin_unlock_irqrestore(&usbhid->lock, flags);
                        return;
                }
        }

        clear_bit(HID_OUT_RUNNING, &usbhid->iofl);
        spin_unlock_irqrestore(&usbhid->lock, flags);
        usb_autopm_put_interface_async(usbhid->intf);
        wake_up(&usbhid->wait);
}

/*
 * Control pipe completion handler.
 */

static void hid_ctrl(struct urb *urb)
{
        struct hid_device *hid = urb->context;
        struct usbhid_device *usbhid = hid->driver_data;
        unsigned long flags;
        int unplug = 0, status = urb->status;

        switch (status) {
        case 0:                 /* success */
                if (usbhid->ctrl[usbhid->ctrltail].dir == USB_DIR_IN)
                        hid_input_report(urb->context,
                                usbhid->ctrl[usbhid->ctrltail].report->type,
                                urb->transfer_buffer, urb->actual_length, 0);
                break;
        case -ESHUTDOWN:        /* unplug */
                unplug = 1;
                break;
        case -EILSEQ:           /* protocol error or unplug */
        case -EPROTO:           /* protocol error or unplug */
        case -ECONNRESET:       /* unlink */
        case -ENOENT:
        case -EPIPE:            /* report not available */
                break;
        default:                /* error */
                hid_warn(urb->dev, "ctrl urb status %d received\n", status);
        }

        spin_lock_irqsave(&usbhid->lock, flags);

        if (unplug) {
                usbhid->ctrltail = usbhid->ctrlhead;
        } else if (usbhid->ctrlhead != usbhid->ctrltail) {
                usbhid->ctrltail = (usbhid->ctrltail + 1) & (HID_CONTROL_FIFO_SIZE - 1);

                if (usbhid->ctrlhead != usbhid->ctrltail &&
                                hid_submit_ctrl(hid) == 0) {
                        /* Successfully submitted next urb in queue */
                        spin_unlock_irqrestore(&usbhid->lock, flags);
                        return;
                }
        }

        clear_bit(HID_CTRL_RUNNING, &usbhid->iofl);
        spin_unlock_irqrestore(&usbhid->lock, flags);
        usb_autopm_put_interface_async(usbhid->intf);
        wake_up(&usbhid->wait);
}

static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *report,
                                   unsigned char dir)
{
        int head;
        struct usbhid_device *usbhid = hid->driver_data;

        if (((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN) ||
                test_bit(HID_DISCONNECTED, &usbhid->iofl))
                return;

        if (usbhid->urbout && dir == USB_DIR_OUT && report->type == HID_OUTPUT_REPORT) {
                if ((head = (usbhid->outhead + 1) & (HID_OUTPUT_FIFO_SIZE - 1)) == usbhid->outtail) {
                        hid_warn(hid, "output queue full\n");
                        return;
                }

                usbhid->out[usbhid->outhead].raw_report = hid_alloc_report_buf(report, GFP_ATOMIC);
                if (!usbhid->out[usbhid->outhead].raw_report) {
                        hid_warn(hid, "output queueing failed\n");
                        return;
                }
                hid_output_report(report, usbhid->out[usbhid->outhead].raw_report);
                usbhid->out[usbhid->outhead].report = report;
                usbhid->outhead = head;

                /* If the queue isn't running, restart it */
                if (!test_bit(HID_OUT_RUNNING, &usbhid->iofl)) {
                        usbhid_restart_out_queue(usbhid);

                /* Otherwise see if an earlier request has timed out */
                } else if (time_after(jiffies, usbhid->last_out + HZ * 5)) {

                        /* Prevent autosuspend following the unlink */
                        usb_autopm_get_interface_no_resume(usbhid->intf);

                        /*
                         * Prevent resubmission in case the URB completes
                         * before we can unlink it.  We don't want to cancel
                         * the wrong transfer!
                         */
                        usb_block_urb(usbhid->urbout);

                        /* Drop lock to avoid deadlock if the callback runs */
                        spin_unlock(&usbhid->lock);

                        usb_unlink_urb(usbhid->urbout);
                        spin_lock(&usbhid->lock);
                        usb_unblock_urb(usbhid->urbout);

                        /* Unlink might have stopped the queue */
                        if (!test_bit(HID_OUT_RUNNING, &usbhid->iofl))
                                usbhid_restart_out_queue(usbhid);

                        /* Now we can allow autosuspend again */
                        usb_autopm_put_interface_async(usbhid->intf);
                }
                return;
        }

        if ((head = (usbhid->ctrlhead + 1) & (HID_CONTROL_FIFO_SIZE - 1)) == usbhid->ctrltail) {
                hid_warn(hid, "control queue full\n");
                return;
        }

        if (dir == USB_DIR_OUT) {
                usbhid->ctrl[usbhid->ctrlhead].raw_report = hid_alloc_report_buf(report, GFP_ATOMIC);
                if (!usbhid->ctrl[usbhid->ctrlhead].raw_report) {
                        hid_warn(hid, "control queueing failed\n");
                        return;
                }
                hid_output_report(report, usbhid->ctrl[usbhid->ctrlhead].raw_report);
        }
        usbhid->ctrl[usbhid->ctrlhead].report = report;
        usbhid->ctrl[usbhid->ctrlhead].dir = dir;
        usbhid->ctrlhead = head;

        /* If the queue isn't running, restart it */
        if (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl)) {
                usbhid_restart_ctrl_queue(usbhid);

        /* Otherwise see if an earlier request has timed out */
        } else if (time_after(jiffies, usbhid->last_ctrl + HZ * 5)) {

                /* Prevent autosuspend following the unlink */
                usb_autopm_get_interface_no_resume(usbhid->intf);

                /*
                 * Prevent resubmission in case the URB completes
                 * before we can unlink it.  We don't want to cancel
                 * the wrong transfer!
                 */
                usb_block_urb(usbhid->urbctrl);

                /* Drop lock to avoid deadlock if the callback runs */
                spin_unlock(&usbhid->lock);

                usb_unlink_urb(usbhid->urbctrl);
                spin_lock(&usbhid->lock);
                usb_unblock_urb(usbhid->urbctrl);

                /* Unlink might have stopped the queue */
                if (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl))
                        usbhid_restart_ctrl_queue(usbhid);

                /* Now we can allow autosuspend again */
                usb_autopm_put_interface_async(usbhid->intf);
        }
}

static void usbhid_submit_report(struct hid_device *hid, struct hid_report *report, unsigned char dir)
{
        struct usbhid_device *usbhid = hid->driver_data;
        unsigned long flags;

        spin_lock_irqsave(&usbhid->lock, flags);
        __usbhid_submit_report(hid, report, dir);
        spin_unlock_irqrestore(&usbhid->lock, flags);
}

static int usbhid_wait_io(struct hid_device *hid)
{
        struct usbhid_device *usbhid = hid->driver_data;

        if (!wait_event_timeout(usbhid->wait,
                                (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl) &&
                                !test_bit(HID_OUT_RUNNING, &usbhid->iofl)),
                                        10*HZ)) {
                dbg_hid("timeout waiting for ctrl or out queue to clear\n");
                return -1;
        }

        return 0;
}

static int hid_set_idle(struct usb_device *dev, int ifnum, int report, int idle)
{
        return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                HID_REQ_SET_IDLE, USB_TYPE_CLASS | USB_RECIP_INTERFACE, (idle << 8) | report,
                ifnum, NULL, 0, USB_CTRL_SET_TIMEOUT);
}

static int hid_get_class_descriptor(struct usb_device *dev, int ifnum,
                unsigned char type, void *buf, int size)
{
        int result, retries = 4;

        memset(buf, 0, size);

        do {
                result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
                                USB_REQ_GET_DESCRIPTOR, USB_RECIP_INTERFACE | USB_DIR_IN,
                                (type << 8), ifnum, buf, size, USB_CTRL_GET_TIMEOUT);
                retries--;
        } while (result < size && retries);
        return result;
}

static int usbhid_open(struct hid_device *hid)
{
        struct usbhid_device *usbhid = hid->driver_data;
        int res;

        mutex_lock(&usbhid->mutex);

        set_bit(HID_OPENED, &usbhid->iofl);

        if (hid->quirks & HID_QUIRK_ALWAYS_POLL) {
                res = 0;
                goto Done;
        }

        res = usb_autopm_get_interface(usbhid->intf);
        /* the device must be awake to reliably request remote wakeup */
        if (res < 0) {
                clear_bit(HID_OPENED, &usbhid->iofl);
                res = -EIO;
                goto Done;
        }

        usbhid->intf->needs_remote_wakeup = 1;

        set_bit(HID_RESUME_RUNNING, &usbhid->iofl);
        set_bit(HID_IN_POLLING, &usbhid->iofl);

        res = hid_start_in(hid);
        if (res) {
                if (res != -ENOSPC) {
                        hid_io_error(hid);
                        res = 0;
                } else {
                        /* no use opening if resources are insufficient */
                        res = -EBUSY;
                        clear_bit(HID_OPENED, &usbhid->iofl);
                        clear_bit(HID_IN_POLLING, &usbhid->iofl);
                        usbhid->intf->needs_remote_wakeup = 0;
                }
        }

        usb_autopm_put_interface(usbhid->intf);

        /*
         * In case events are generated while nobody was listening,
         * some are released when the device is re-opened.
         * Wait 50 msec for the queue to empty before allowing events
         * to go through hid.
         */
        if (res == 0)
                msleep(50);

        clear_bit(HID_RESUME_RUNNING, &usbhid->iofl);

 Done:
        mutex_unlock(&usbhid->mutex);
        return res;
}

static void usbhid_close(struct hid_device *hid)
{
        struct usbhid_device *usbhid = hid->driver_data;

        mutex_lock(&usbhid->mutex);

        /*
         * Make sure we don't restart data acquisition due to
         * a resumption we no longer care about by avoiding racing
         * with hid_start_in().
         */
        spin_lock_irq(&usbhid->lock);
        clear_bit(HID_OPENED, &usbhid->iofl);
        if (!(hid->quirks & HID_QUIRK_ALWAYS_POLL))
                clear_bit(HID_IN_POLLING, &usbhid->iofl);
        spin_unlock_irq(&usbhid->lock);

        if (!(hid->quirks & HID_QUIRK_ALWAYS_POLL)) {
                hid_cancel_delayed_stuff(usbhid);
                usb_kill_urb(usbhid->urbin);
                usbhid->intf->needs_remote_wakeup = 0;
        }

        mutex_unlock(&usbhid->mutex);
}

/*
 * Initialize all reports
 */

void usbhid_init_reports(struct hid_device *hid)
{
        struct hid_report *report;
        struct usbhid_device *usbhid = hid->driver_data;
        struct hid_report_enum *report_enum;
        int err, ret;

        report_enum = &hid->report_enum[HID_INPUT_REPORT];
        list_for_each_entry(report, &report_enum->report_list, list)
                usbhid_submit_report(hid, report, USB_DIR_IN);

        report_enum = &hid->report_enum[HID_FEATURE_REPORT];
        list_for_each_entry(report, &report_enum->report_list, list)
                usbhid_submit_report(hid, report, USB_DIR_IN);

        err = 0;
        ret = usbhid_wait_io(hid);
        while (ret) {
                err |= ret;
                if (test_bit(HID_CTRL_RUNNING, &usbhid->iofl))
                        usb_kill_urb(usbhid->urbctrl);
                if (test_bit(HID_OUT_RUNNING, &usbhid->iofl))
                        usb_kill_urb(usbhid->urbout);
                ret = usbhid_wait_io(hid);
        }

        if (err)
                hid_warn(hid, "timeout initializing reports\n");
}

/*
 * Reset LEDs which BIOS might have left on. For now, just NumLock (0x01).
 */
static int hid_find_field_early(struct hid_device *hid, unsigned int page,
    unsigned int hid_code, struct hid_field **pfield)
{
        struct hid_report *report;
        struct hid_field *field;
        struct hid_usage *usage;
        int i, j;

        list_for_each_entry(report, &hid->report_enum[HID_OUTPUT_REPORT].report_list, list) {
                for (i = 0; i < report->maxfield; i++) {
                        field = report->field[i];
                        for (j = 0; j < field->maxusage; j++) {
                                usage = &field->usage[j];
                                if ((usage->hid & HID_USAGE_PAGE) == page &&
                                    (usage->hid & 0xFFFF) == hid_code) {
                                        *pfield = field;
                                        return j;
                                }
                        }
                }
        }
        return -1;
}

static void usbhid_set_leds(struct hid_device *hid)
{
        struct hid_field *field;
        int offset;

        if ((offset = hid_find_field_early(hid, HID_UP_LED, 0x01, &field)) != -1) {
                hid_set_field(field, offset, 0);
                usbhid_submit_report(hid, field->report, USB_DIR_OUT);
        }
}

/*
 * Traverse the supplied list of reports and find the longest
 */
static void hid_find_max_report(struct hid_device *hid, unsigned int type,
                unsigned int *max)
{
        struct hid_report *report;
        unsigned int size;

        list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
                size = ((report->size - 1) >> 3) + 1 + hid->report_enum[type].numbered;
                if (*max < size)
                        *max = size;
        }
}

static int hid_alloc_buffers(struct usb_device *dev, struct hid_device *hid)
{
        struct usbhid_device *usbhid = hid->driver_data;

        usbhid->inbuf = usb_alloc_coherent(dev, usbhid->bufsize, GFP_KERNEL,
                        &usbhid->inbuf_dma);
        usbhid->outbuf = usb_alloc_coherent(dev, usbhid->bufsize, GFP_KERNEL,
                        &usbhid->outbuf_dma);
        usbhid->cr = kmalloc_obj(*usbhid->cr);
        usbhid->ctrlbuf = usb_alloc_coherent(dev, usbhid->bufsize, GFP_KERNEL,
                        &usbhid->ctrlbuf_dma);
        if (!usbhid->inbuf || !usbhid->outbuf || !usbhid->cr ||
                        !usbhid->ctrlbuf)
                return -1;

        return 0;
}

static int usbhid_get_raw_report(struct hid_device *hid,
                unsigned char report_number, __u8 *buf, size_t count,
                unsigned char report_type)
{
        struct usbhid_device *usbhid = hid->driver_data;
        struct usb_device *dev = hid_to_usb_dev(hid);
        struct usb_interface *intf = usbhid->intf;
        struct usb_host_interface *interface = intf->cur_altsetting;
        int skipped_report_id = 0;
        int ret;

        /* Byte 0 is the report number. Report data starts at byte 1.*/
        buf[0] = report_number;
        if (report_number == 0x0) {
                /* Offset the return buffer by 1, so that the report ID
                   will remain in byte 0. */
                buf++;
                count--;
                skipped_report_id = 1;
        }
        ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
                HID_REQ_GET_REPORT,
                USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
                ((report_type + 1) << 8) | report_number,
                interface->desc.bInterfaceNumber, buf, count,
                USB_CTRL_SET_TIMEOUT);

        /* count also the report id */
        if (ret > 0 && skipped_report_id)
                ret++;

        return ret;
}

static int usbhid_set_raw_report(struct hid_device *hid, unsigned int reportnum,
                                 __u8 *buf, size_t count, unsigned char rtype)
{
        struct usbhid_device *usbhid = hid->driver_data;
        struct usb_device *dev = hid_to_usb_dev(hid);
        struct usb_interface *intf = usbhid->intf;
        struct usb_host_interface *interface = intf->cur_altsetting;
        int ret, skipped_report_id = 0;

        /* Byte 0 is the report number. Report data starts at byte 1.*/
        if ((rtype == HID_OUTPUT_REPORT) &&
            (hid->quirks & HID_QUIRK_SKIP_OUTPUT_REPORT_ID))
                buf[0] = 0;
        else
                buf[0] = reportnum;

        if (buf[0] == 0x0) {
                /* Don't send the Report ID */
                buf++;
                count--;
                skipped_report_id = 1;
        }

        ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                        HID_REQ_SET_REPORT,
                        USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
                        ((rtype + 1) << 8) | reportnum,
                        interface->desc.bInterfaceNumber, buf, count,
                        USB_CTRL_SET_TIMEOUT);
        /* count also the report id, if this was a numbered report. */
        if (ret > 0 && skipped_report_id)
                ret++;

        return ret;
}

static int usbhid_output_report(struct hid_device *hid, __u8 *buf, size_t count)
{
        struct usbhid_device *usbhid = hid->driver_data;
        struct usb_device *dev = hid_to_usb_dev(hid);
        int actual_length, skipped_report_id = 0, ret;

        if (!usbhid->urbout)
                return -ENOSYS;

        if (buf[0] == 0x0) {
                /* Don't send the Report ID */
                buf++;
                count--;
                skipped_report_id = 1;
        }

        ret = usb_interrupt_msg(dev, usbhid->urbout->pipe,
                                buf, count, &actual_length,
                                USB_CTRL_SET_TIMEOUT);
        /* return the number of bytes transferred */
        if (ret == 0) {
                ret = actual_length;
                /* count also the report id */
                if (skipped_report_id)
                        ret++;
        }

        return ret;
}

static void hid_free_buffers(struct usb_device *dev, struct hid_device *hid)
{
        struct usbhid_device *usbhid = hid->driver_data;

        usb_free_coherent(dev, usbhid->bufsize, usbhid->inbuf, usbhid->inbuf_dma);
        usb_free_coherent(dev, usbhid->bufsize, usbhid->outbuf, usbhid->outbuf_dma);
        kfree(usbhid->cr);
        usb_free_coherent(dev, usbhid->bufsize, usbhid->ctrlbuf, usbhid->ctrlbuf_dma);
}

static int usbhid_parse(struct hid_device *hid)
{
        struct usb_interface *intf = to_usb_interface(hid->dev.parent);
        struct usb_host_interface *interface = intf->cur_altsetting;
        struct usb_device *dev = interface_to_usbdev (intf);
        struct hid_descriptor *hdesc;
        struct hid_class_descriptor *hcdesc;
        __u8 fixed_opt_descriptors_size;
        u32 quirks = 0;
        unsigned int rsize = 0;
        char *rdesc;
        int ret;

        quirks = hid_lookup_quirk(hid);

        if (quirks & HID_QUIRK_IGNORE)
                return -ENODEV;

        /* Many keyboards and mice don't like to be polled for reports,
         * so we will always set the HID_QUIRK_NOGET flag for them. */
        if (interface->desc.bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {
                if (interface->desc.bInterfaceProtocol == USB_INTERFACE_PROTOCOL_KEYBOARD ||
                        interface->desc.bInterfaceProtocol == USB_INTERFACE_PROTOCOL_MOUSE)
                                quirks |= HID_QUIRK_NOGET;
        }

        if (usb_get_extra_descriptor(interface, HID_DT_HID, &hdesc) &&
            (!interface->desc.bNumEndpoints ||
             usb_get_extra_descriptor(&interface->endpoint[0], HID_DT_HID, &hdesc))) {
                dbg_hid("class descriptor not present\n");
                return -ENODEV;
        }

        if (!hdesc->bNumDescriptors ||
            hdesc->bLength != sizeof(*hdesc) +
                              (hdesc->bNumDescriptors - 1) * sizeof(*hcdesc)) {
                dbg_hid("hid descriptor invalid, bLen=%hhu bNum=%hhu\n",
                        hdesc->bLength, hdesc->bNumDescriptors);

                /*
                 * Some devices may expose a wrong number of descriptors compared
                 * to the provided length.
                 * However, we ignore the optional hid class descriptors entirely
                 * so we can safely recompute the proper field.
                 */
                if (hdesc->bLength >= sizeof(*hdesc)) {
                        fixed_opt_descriptors_size = hdesc->bLength - sizeof(*hdesc);

                        hid_warn(intf, "fixing wrong optional hid class descriptors count\n");
                        hdesc->bNumDescriptors = fixed_opt_descriptors_size / sizeof(*hcdesc) + 1;
                } else {
                        return -EINVAL;
                }
        }

        hid->version = le16_to_cpu(hdesc->bcdHID);
        hid->country = hdesc->bCountryCode;

        if (hdesc->rpt_desc.bDescriptorType == HID_DT_REPORT)
                rsize = le16_to_cpu(hdesc->rpt_desc.wDescriptorLength);

        if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
                dbg_hid("weird size of report descriptor (%u)\n", rsize);
                return -EINVAL;
        }

        rdesc = kmalloc(rsize, GFP_KERNEL);
        if (!rdesc)
                return -ENOMEM;

        hid_set_idle(dev, interface->desc.bInterfaceNumber, 0, 0);

        ret = hid_get_class_descriptor(dev, interface->desc.bInterfaceNumber,
                        HID_DT_REPORT, rdesc, rsize);
        if (ret < 0) {
                dbg_hid("reading report descriptor failed\n");
                kfree(rdesc);
                goto err;
        }

        ret = hid_parse_report(hid, rdesc, rsize);
        kfree(rdesc);
        if (ret) {
                dbg_hid("parsing report descriptor failed\n");
                goto err;
        }

        if (hdesc->bNumDescriptors > 1)
                hid_warn(intf,
                        "%u unsupported optional hid class descriptors\n",
                        (int)(hdesc->bNumDescriptors - 1));

        hid->quirks |= quirks;

        return 0;
err:
        return ret;
}

static int usbhid_start(struct hid_device *hid)
{
        struct usb_interface *intf = to_usb_interface(hid->dev.parent);
        struct usb_host_interface *interface = intf->cur_altsetting;
        struct usb_device *dev = interface_to_usbdev(intf);
        struct usbhid_device *usbhid = hid->driver_data;
        unsigned int n, insize = 0;
        int ret;

        mutex_lock(&usbhid->mutex);

        clear_bit(HID_DISCONNECTED, &usbhid->iofl);

        usbhid->bufsize = HID_MIN_BUFFER_SIZE;
        hid_find_max_report(hid, HID_INPUT_REPORT, &usbhid->bufsize);
        hid_find_max_report(hid, HID_OUTPUT_REPORT, &usbhid->bufsize);
        hid_find_max_report(hid, HID_FEATURE_REPORT, &usbhid->bufsize);

        if (usbhid->bufsize > HID_MAX_BUFFER_SIZE)
                usbhid->bufsize = HID_MAX_BUFFER_SIZE;

        hid_find_max_report(hid, HID_INPUT_REPORT, &insize);

        if (insize > HID_MAX_BUFFER_SIZE)
                insize = HID_MAX_BUFFER_SIZE;

        if (hid_alloc_buffers(dev, hid)) {
                ret = -ENOMEM;
                goto fail;
        }

        for (n = 0; n < interface->desc.bNumEndpoints; n++) {
                struct usb_endpoint_descriptor *endpoint;
                int pipe;
                int interval;

                endpoint = &interface->endpoint[n].desc;
                if (!usb_endpoint_xfer_int(endpoint))
                        continue;

                interval = endpoint->bInterval;

                /* Some vendors give fullspeed interval on highspeed devices */
                if (hid->quirks & HID_QUIRK_FULLSPEED_INTERVAL &&
                    dev->speed == USB_SPEED_HIGH) {
                        interval = fls(endpoint->bInterval*8);
                        pr_info("%s: Fixing fullspeed to highspeed interval: %d -> %d\n",
                                hid->name, endpoint->bInterval, interval);
                }

                /* Change the polling interval of mice, joysticks
                 * and keyboards.
                 */
                switch (hid->collection->usage) {
                case HID_GD_MOUSE:
                        if (hid_mousepoll_interval > 0)
                                interval = hid_mousepoll_interval;
                        break;
                case HID_GD_JOYSTICK:
                        if (hid_jspoll_interval > 0)
                                interval = hid_jspoll_interval;
                        break;
                case HID_GD_KEYBOARD:
                        if (hid_kbpoll_interval > 0)
                                interval = hid_kbpoll_interval;
                        break;
                }

                ret = -ENOMEM;
                if (usb_endpoint_dir_in(endpoint)) {
                        if (usbhid->urbin)
                                continue;
                        if (!(usbhid->urbin = usb_alloc_urb(0, GFP_KERNEL)))
                                goto fail;
                        pipe = usb_rcvintpipe(dev, endpoint->bEndpointAddress);
                        usb_fill_int_urb(usbhid->urbin, dev, pipe, usbhid->inbuf, insize,
                                         hid_irq_in, hid, interval);
                        usbhid->urbin->transfer_dma = usbhid->inbuf_dma;
                        usbhid->urbin->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
                } else {
                        if (usbhid->urbout)
                                continue;
                        if (!(usbhid->urbout = usb_alloc_urb(0, GFP_KERNEL)))
                                goto fail;
                        pipe = usb_sndintpipe(dev, endpoint->bEndpointAddress);
                        usb_fill_int_urb(usbhid->urbout, dev, pipe, usbhid->outbuf, 0,
                                         hid_irq_out, hid, interval);
                        usbhid->urbout->transfer_dma = usbhid->outbuf_dma;
                        usbhid->urbout->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
                }
        }

        usbhid->urbctrl = usb_alloc_urb(0, GFP_KERNEL);
        if (!usbhid->urbctrl) {
                ret = -ENOMEM;
                goto fail;
        }

        usb_fill_control_urb(usbhid->urbctrl, dev, 0, (void *) usbhid->cr,
                             usbhid->ctrlbuf, 1, hid_ctrl, hid);
        usbhid->urbctrl->transfer_dma = usbhid->ctrlbuf_dma;
        usbhid->urbctrl->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

        set_bit(HID_STARTED, &usbhid->iofl);

        if (hid->quirks & HID_QUIRK_ALWAYS_POLL) {
                ret = usb_autopm_get_interface(usbhid->intf);
                if (ret)
                        goto fail;
                set_bit(HID_IN_POLLING, &usbhid->iofl);
                usbhid->intf->needs_remote_wakeup = 1;
                ret = hid_start_in(hid);
                if (ret) {
                        dev_err(&hid->dev,
                                "failed to start in urb: %d\n", ret);
                }
                usb_autopm_put_interface(usbhid->intf);
        }

        /* Some keyboards don't work until their LEDs have been set.
         * Since BIOSes do set the LEDs, it must be safe for any device
         * that supports the keyboard boot protocol.
         * In addition, enable remote wakeup by default for all keyboard
         * devices supporting the boot protocol.
         */
        if (interface->desc.bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT &&
                        interface->desc.bInterfaceProtocol ==
                                USB_INTERFACE_PROTOCOL_KEYBOARD) {
                usbhid_set_leds(hid);
                device_set_wakeup_enable(&dev->dev, 1);
        }

        mutex_unlock(&usbhid->mutex);
        return 0;

fail:
        usb_free_urb(usbhid->urbin);
        usb_free_urb(usbhid->urbout);
        usb_free_urb(usbhid->urbctrl);
        usbhid->urbin = NULL;
        usbhid->urbout = NULL;
        usbhid->urbctrl = NULL;
        hid_free_buffers(dev, hid);
        mutex_unlock(&usbhid->mutex);
        return ret;
}

static void usbhid_stop(struct hid_device *hid)
{
        struct usbhid_device *usbhid = hid->driver_data;

        if (WARN_ON(!usbhid))
                return;

        if (hid->quirks & HID_QUIRK_ALWAYS_POLL) {
                clear_bit(HID_IN_POLLING, &usbhid->iofl);
                usbhid->intf->needs_remote_wakeup = 0;
        }

        mutex_lock(&usbhid->mutex);

        clear_bit(HID_STARTED, &usbhid->iofl);

        spin_lock_irq(&usbhid->lock);   /* Sync with error and led handlers */
        set_bit(HID_DISCONNECTED, &usbhid->iofl);
        while (usbhid->ctrltail != usbhid->ctrlhead) {
                if (usbhid->ctrl[usbhid->ctrltail].dir == USB_DIR_OUT) {
                        kfree(usbhid->ctrl[usbhid->ctrltail].raw_report);
                        usbhid->ctrl[usbhid->ctrltail].raw_report = NULL;
                }

                usbhid->ctrltail = (usbhid->ctrltail + 1) &
                        (HID_CONTROL_FIFO_SIZE - 1);
        }
        spin_unlock_irq(&usbhid->lock);

        usb_kill_urb(usbhid->urbin);
        usb_kill_urb(usbhid->urbout);
        usb_kill_urb(usbhid->urbctrl);

        hid_cancel_delayed_stuff(usbhid);

        hid->claimed = 0;

        usb_free_urb(usbhid->urbin);
        usb_free_urb(usbhid->urbctrl);
        usb_free_urb(usbhid->urbout);
        usbhid->urbin = NULL; /* don't mess up next start */
        usbhid->urbctrl = NULL;
        usbhid->urbout = NULL;

        hid_free_buffers(hid_to_usb_dev(hid), hid);

        mutex_unlock(&usbhid->mutex);
}

static int usbhid_power(struct hid_device *hid, int lvl)
{
        struct usbhid_device *usbhid = hid->driver_data;
        int r = 0;

        switch (lvl) {
        case PM_HINT_FULLON:
                r = usb_autopm_get_interface(usbhid->intf);
                break;

        case PM_HINT_NORMAL:
                usb_autopm_put_interface(usbhid->intf);
                break;
        }

        return r;
}

static void usbhid_request(struct hid_device *hid, struct hid_report *rep, int reqtype)
{
        switch (reqtype) {
        case HID_REQ_GET_REPORT:
                usbhid_submit_report(hid, rep, USB_DIR_IN);
                break;
        case HID_REQ_SET_REPORT:
                usbhid_submit_report(hid, rep, USB_DIR_OUT);
                break;
        }
}

static int usbhid_raw_request(struct hid_device *hid, unsigned char reportnum,
                              __u8 *buf, size_t len, unsigned char rtype,
                              int reqtype)
{
        switch (reqtype) {
        case HID_REQ_GET_REPORT:
                return usbhid_get_raw_report(hid, reportnum, buf, len, rtype);
        case HID_REQ_SET_REPORT:
                return usbhid_set_raw_report(hid, reportnum, buf, len, rtype);
        default:
                return -EIO;
        }
}

static int usbhid_idle(struct hid_device *hid, int report, int idle,
                int reqtype)
{
        struct usb_device *dev = hid_to_usb_dev(hid);
        struct usb_interface *intf = to_usb_interface(hid->dev.parent);
        struct usb_host_interface *interface = intf->cur_altsetting;
        int ifnum = interface->desc.bInterfaceNumber;

        if (reqtype != HID_REQ_SET_IDLE)
                return -EINVAL;

        return hid_set_idle(dev, ifnum, report, idle);
}

static bool usbhid_may_wakeup(struct hid_device *hid)
{
        struct usb_device *dev = hid_to_usb_dev(hid);

        return device_may_wakeup(&dev->dev);
}

static const struct hid_ll_driver usb_hid_driver = {
        .parse = usbhid_parse,
        .start = usbhid_start,
        .stop = usbhid_stop,
        .open = usbhid_open,
        .close = usbhid_close,
        .power = usbhid_power,
        .request = usbhid_request,
        .wait = usbhid_wait_io,
        .raw_request = usbhid_raw_request,
        .output_report = usbhid_output_report,
        .idle = usbhid_idle,
        .may_wakeup = usbhid_may_wakeup,
};

bool hid_is_usb(const struct hid_device *hdev)
{
        return hdev->ll_driver == &usb_hid_driver;
}
EXPORT_SYMBOL_GPL(hid_is_usb);

static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
        struct usb_host_interface *interface = intf->cur_altsetting;
        struct usb_device *dev = interface_to_usbdev(intf);
        struct usbhid_device *usbhid;
        struct hid_device *hid;
        unsigned int n, has_in = 0;
        size_t len;
        int ret;

        dbg_hid("HID probe called for ifnum %d\n",
                        intf->altsetting->desc.bInterfaceNumber);

        for (n = 0; n < interface->desc.bNumEndpoints; n++)
                if (usb_endpoint_is_int_in(&interface->endpoint[n].desc))
                        has_in++;
        if (!has_in) {
                hid_err(intf, "couldn't find an input interrupt endpoint\n");
                return -ENODEV;
        }

        hid = hid_allocate_device();
        if (IS_ERR(hid))
                return PTR_ERR(hid);

        usb_set_intfdata(intf, hid);
        hid->ll_driver = &usb_hid_driver;
        hid->ff_init = hid_pidff_init;
#ifdef CONFIG_USB_HIDDEV
        hid->hiddev_connect = hiddev_connect;
        hid->hiddev_disconnect = hiddev_disconnect;
        hid->hiddev_hid_event = hiddev_hid_event;
        hid->hiddev_report_event = hiddev_report_event;
#endif
        hid->dev.parent = &intf->dev;
        device_set_node(&hid->dev, dev_fwnode(&intf->dev));
        hid->bus = BUS_USB;
        hid->vendor = le16_to_cpu(dev->descriptor.idVendor);
        hid->product = le16_to_cpu(dev->descriptor.idProduct);
        hid->version = le16_to_cpu(dev->descriptor.bcdDevice);
        hid->name[0] = 0;
        if (intf->cur_altsetting->desc.bInterfaceProtocol ==
                        USB_INTERFACE_PROTOCOL_MOUSE)
                hid->type = HID_TYPE_USBMOUSE;
        else if (intf->cur_altsetting->desc.bInterfaceProtocol == 0)
                hid->type = HID_TYPE_USBNONE;

        if (dev->manufacturer)
                strscpy(hid->name, dev->manufacturer, sizeof(hid->name));

        if (dev->product) {
                if (dev->manufacturer)
                        strlcat(hid->name, " ", sizeof(hid->name));
                strlcat(hid->name, dev->product, sizeof(hid->name));
        }

        if (!strlen(hid->name))
                snprintf(hid->name, sizeof(hid->name), "HID %04x:%04x",
                         le16_to_cpu(dev->descriptor.idVendor),
                         le16_to_cpu(dev->descriptor.idProduct));

        usb_make_path(dev, hid->phys, sizeof(hid->phys));
        strlcat(hid->phys, "/input", sizeof(hid->phys));
        len = strlen(hid->phys);
        if (len < sizeof(hid->phys) - 1)
                snprintf(hid->phys + len, sizeof(hid->phys) - len,
                         "%d", intf->altsetting[0].desc.bInterfaceNumber);

        if (usb_string(dev, dev->descriptor.iSerialNumber, hid->uniq, 64) <= 0)
                hid->uniq[0] = 0;

        usbhid = kzalloc_obj(*usbhid);
        if (usbhid == NULL) {
                ret = -ENOMEM;
                goto err;
        }

        hid->driver_data = usbhid;
        usbhid->hid = hid;
        usbhid->intf = intf;
        usbhid->ifnum = interface->desc.bInterfaceNumber;

        init_waitqueue_head(&usbhid->wait);
        INIT_WORK(&usbhid->reset_work, hid_reset);
        timer_setup(&usbhid->io_retry, hid_retry_timeout, 0);
        spin_lock_init(&usbhid->lock);
        mutex_init(&usbhid->mutex);

        ret = hid_add_device(hid);
        if (ret) {
                if (ret != -ENODEV)
                        hid_err(intf, "can't add hid device: %d\n", ret);
                goto err_free;
        }

        return 0;
err_free:
        kfree(usbhid);
err:
        hid_destroy_device(hid);
        return ret;
}

static void usbhid_disconnect(struct usb_interface *intf)
{
        struct hid_device *hid = usb_get_intfdata(intf);
        struct usbhid_device *usbhid;

        if (WARN_ON(!hid))
                return;

        usbhid = hid->driver_data;
        spin_lock_irq(&usbhid->lock);   /* Sync with error and led handlers */
        set_bit(HID_DISCONNECTED, &usbhid->iofl);
        spin_unlock_irq(&usbhid->lock);
        hid_destroy_device(hid);
        kfree(usbhid);
}

static void hid_cancel_delayed_stuff(struct usbhid_device *usbhid)
{
        timer_delete_sync(&usbhid->io_retry);
        cancel_work_sync(&usbhid->reset_work);
}

static void hid_cease_io(struct usbhid_device *usbhid)
{
        timer_delete_sync(&usbhid->io_retry);
        usb_kill_urb(usbhid->urbin);
        usb_kill_urb(usbhid->urbctrl);
        usb_kill_urb(usbhid->urbout);
}

static void hid_restart_io(struct hid_device *hid)
{
        struct usbhid_device *usbhid = hid->driver_data;
        int clear_halt = test_bit(HID_CLEAR_HALT, &usbhid->iofl);
        int reset_pending = test_bit(HID_RESET_PENDING, &usbhid->iofl);

        spin_lock_irq(&usbhid->lock);
        clear_bit(HID_SUSPENDED, &usbhid->iofl);
        usbhid_mark_busy(usbhid);

        if (clear_halt || reset_pending)
                schedule_work(&usbhid->reset_work);
        usbhid->retry_delay = 0;
        spin_unlock_irq(&usbhid->lock);

        if (reset_pending || !test_bit(HID_STARTED, &usbhid->iofl))
                return;

        if (!clear_halt) {
                if (hid_start_in(hid) < 0)
                        hid_io_error(hid);
        }

        spin_lock_irq(&usbhid->lock);
        if (usbhid->urbout && !test_bit(HID_OUT_RUNNING, &usbhid->iofl))
                usbhid_restart_out_queue(usbhid);
        if (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl))
                usbhid_restart_ctrl_queue(usbhid);
        spin_unlock_irq(&usbhid->lock);
}

/* Treat USB reset pretty much the same as suspend/resume */
static int hid_pre_reset(struct usb_interface *intf)
{
        struct hid_device *hid = usb_get_intfdata(intf);
        struct usbhid_device *usbhid = hid->driver_data;

        spin_lock_irq(&usbhid->lock);
        set_bit(HID_RESET_PENDING, &usbhid->iofl);
        spin_unlock_irq(&usbhid->lock);
        hid_cease_io(usbhid);

        return 0;
}

/* Same routine used for post_reset and reset_resume */
static int hid_post_reset(struct usb_interface *intf)
{
        struct usb_device *dev = interface_to_usbdev (intf);
        struct hid_device *hid = usb_get_intfdata(intf);
        struct usbhid_device *usbhid = hid->driver_data;
        struct usb_host_interface *interface = intf->cur_altsetting;
        int status;
        char *rdesc;

        /* Fetch and examine the HID report descriptor. If this
         * has changed, then rebind. Since usbcore's check of the
         * configuration descriptors passed, we already know that
         * the size of the HID report descriptor has not changed.
         */
        rdesc = kmalloc(hid->dev_rsize, GFP_KERNEL);
        if (!rdesc)
                return -ENOMEM;

        status = hid_get_class_descriptor(dev,
                                interface->desc.bInterfaceNumber,
                                HID_DT_REPORT, rdesc, hid->dev_rsize);
        if (status < 0) {
                dbg_hid("reading report descriptor failed (post_reset)\n");
                kfree(rdesc);
                return status;
        }
        status = memcmp(rdesc, hid->dev_rdesc, hid->dev_rsize);
        kfree(rdesc);
        if (status != 0) {
                dbg_hid("report descriptor changed\n");
                return -EPERM;
        }

        /* No need to do another reset or clear a halted endpoint */
        spin_lock_irq(&usbhid->lock);
        clear_bit(HID_RESET_PENDING, &usbhid->iofl);
        clear_bit(HID_CLEAR_HALT, &usbhid->iofl);
        spin_unlock_irq(&usbhid->lock);
        hid_set_idle(dev, intf->cur_altsetting->desc.bInterfaceNumber, 0, 0);

        hid_restart_io(hid);

        return 0;
}

static int hid_resume_common(struct hid_device *hid, bool driver_suspended)
{
        int status = 0;

        hid_restart_io(hid);
        if (driver_suspended)
                status = hid_driver_resume(hid);
        return status;
}

static int hid_suspend(struct usb_interface *intf, pm_message_t message)
{
        struct hid_device *hid = usb_get_intfdata(intf);
        struct usbhid_device *usbhid = hid->driver_data;
        int status = 0;
        bool driver_suspended = false;
        unsigned int ledcount;

        if (PMSG_IS_AUTO(message)) {
                ledcount = hidinput_count_leds(hid);
                spin_lock_irq(&usbhid->lock);   /* Sync with error handler */
                if (!test_bit(HID_RESET_PENDING, &usbhid->iofl)
                    && !test_bit(HID_CLEAR_HALT, &usbhid->iofl)
                    && !test_bit(HID_OUT_RUNNING, &usbhid->iofl)
                    && !test_bit(HID_CTRL_RUNNING, &usbhid->iofl)
                    && !test_bit(HID_KEYS_PRESSED, &usbhid->iofl)
                    && (!ledcount || ignoreled))
                {
                        set_bit(HID_SUSPENDED, &usbhid->iofl);
                        spin_unlock_irq(&usbhid->lock);
                        status = hid_driver_suspend(hid, message);
                        if (status < 0)
                                goto failed;
                        driver_suspended = true;
                } else {
                        usbhid_mark_busy(usbhid);
                        spin_unlock_irq(&usbhid->lock);
                        return -EBUSY;
                }

        } else {
                /* TODO: resume() might need to handle suspend failure */
                status = hid_driver_suspend(hid, message);
                driver_suspended = true;
                spin_lock_irq(&usbhid->lock);
                set_bit(HID_SUSPENDED, &usbhid->iofl);
                spin_unlock_irq(&usbhid->lock);
                if (usbhid_wait_io(hid) < 0)
                        status = -EIO;
        }

        hid_cancel_delayed_stuff(usbhid);
        hid_cease_io(usbhid);

        if (PMSG_IS_AUTO(message) && test_bit(HID_KEYS_PRESSED, &usbhid->iofl)) {
                /* lost race against keypresses */
                status = -EBUSY;
                goto failed;
        }
        dev_dbg(&intf->dev, "suspend\n");
        return status;

 failed:
        hid_resume_common(hid, driver_suspended);
        return status;
}

static int hid_resume(struct usb_interface *intf)
{
        struct hid_device *hid = usb_get_intfdata (intf);
        int status;

        status = hid_resume_common(hid, true);
        dev_dbg(&intf->dev, "resume status %d\n", status);
        return 0;
}

static int hid_reset_resume(struct usb_interface *intf)
{
        struct hid_device *hid = usb_get_intfdata(intf);
        int status;

        status = hid_post_reset(intf);
        if (status >= 0) {
                int ret = hid_driver_reset_resume(hid);
                if (ret < 0)
                        status = ret;
        }
        return status;
}

static const struct usb_device_id hid_usb_ids[] = {
        { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
                .bInterfaceClass = USB_INTERFACE_CLASS_HID },
        { }                                             /* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, hid_usb_ids);

static struct usb_driver hid_driver = {
        .name =         "usbhid",
        .probe =        usbhid_probe,
        .disconnect =   usbhid_disconnect,
        .suspend =      pm_ptr(hid_suspend),
        .resume =       pm_ptr(hid_resume),
        .reset_resume = pm_ptr(hid_reset_resume),
        .pre_reset =    hid_pre_reset,
        .post_reset =   hid_post_reset,
        .id_table =     hid_usb_ids,
        .supports_autosuspend = 1,
};

struct usb_interface *usbhid_find_interface(int minor)
{
        return usb_find_interface(&hid_driver, minor);
}

static int __init hid_init(void)
{
        int retval;

        retval = hid_quirks_init(quirks_param, BUS_USB, MAX_USBHID_BOOT_QUIRKS);
        if (retval)
                goto usbhid_quirks_init_fail;
        retval = usb_register(&hid_driver);
        if (retval)
                goto usb_register_fail;
        pr_info(KBUILD_MODNAME ": " DRIVER_DESC "\n");

        return 0;
usb_register_fail:
        hid_quirks_exit(BUS_USB);
usbhid_quirks_init_fail:
        return retval;
}

static void __exit hid_exit(void)
{
        usb_deregister(&hid_driver);
        hid_quirks_exit(BUS_USB);
}

module_init(hid_init);
module_exit(hid_exit);

MODULE_AUTHOR("Andreas Gal");
MODULE_AUTHOR("Vojtech Pavlik");
MODULE_AUTHOR("Jiri Kosina");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");