// SPDX-License-Identifier: GPL-2.0-or-later
 /*
 *  Copyright (c) 2000-2002 Vojtech Pavlik <vojtech@ucw.cz>
 *  Copyright (c) 2001-2002, 2007 Johann Deneux <johann.deneux@gmail.com>
 *
 *  USB/RS232 I-Force joysticks and wheels.
 */

#include <linux/usb.h>
#include "iforce.h"

struct iforce_usb {
        struct iforce iforce;

        struct usb_device *usbdev;
        struct usb_interface *intf;
        struct urb *irq, *out;

        u8 data_in[IFORCE_MAX_LENGTH] ____cacheline_aligned;
        u8 data_out[IFORCE_MAX_LENGTH] ____cacheline_aligned;
};

static void __iforce_usb_xmit(struct iforce *iforce)
{
        struct iforce_usb *iforce_usb = container_of(iforce, struct iforce_usb,
                                                     iforce);
        int n, c;

        guard(spinlock_irqsave)(&iforce->xmit_lock);

        if (iforce->xmit.head == iforce->xmit.tail) {
                iforce_clear_xmit_and_wake(iforce);
                return;
        }

        ((char *)iforce_usb->out->transfer_buffer)[0] = iforce->xmit.buf[iforce->xmit.tail];
        XMIT_INC(iforce->xmit.tail, 1);
        n = iforce->xmit.buf[iforce->xmit.tail];
        XMIT_INC(iforce->xmit.tail, 1);

        iforce_usb->out->transfer_buffer_length = n + 1;
        iforce_usb->out->dev = iforce_usb->usbdev;

        /* Copy rest of data then */
        c = CIRC_CNT_TO_END(iforce->xmit.head, iforce->xmit.tail, XMIT_SIZE);
        if (n < c)
                c = n;

        memcpy(iforce_usb->out->transfer_buffer + 1,
               &iforce->xmit.buf[iforce->xmit.tail],
               c);
        if (n != c) {
                memcpy(iforce_usb->out->transfer_buffer + 1 + c,
                       &iforce->xmit.buf[0],
                       n - c);
        }
        XMIT_INC(iforce->xmit.tail, n);

        n=usb_submit_urb(iforce_usb->out, GFP_ATOMIC);
        if (n) {
                dev_warn(&iforce_usb->intf->dev,
                         "usb_submit_urb failed %d\n", n);
                iforce_clear_xmit_and_wake(iforce);
        }

        /* The IFORCE_XMIT_RUNNING bit is not cleared here. That's intended.
         * As long as the urb completion handler is not called, the transmiting
         * is considered to be running */
}

static void iforce_usb_xmit(struct iforce *iforce)
{
        if (!test_and_set_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags))
                __iforce_usb_xmit(iforce);
}

static int iforce_usb_get_id(struct iforce *iforce, u8 id,
                             u8 *response_data, size_t *response_len)
{
        struct iforce_usb *iforce_usb = container_of(iforce, struct iforce_usb,
                                                     iforce);
        u8 *buf;
        int status;

        buf = kmalloc(IFORCE_MAX_LENGTH, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        status = usb_control_msg(iforce_usb->usbdev,
                                 usb_rcvctrlpipe(iforce_usb->usbdev, 0),
                                 id,
                                 USB_TYPE_VENDOR | USB_DIR_IN |
                                        USB_RECIP_INTERFACE,
                                 0, 0, buf, IFORCE_MAX_LENGTH, 1000);
        if (status < 0) {
                dev_err(&iforce_usb->intf->dev,
                        "usb_submit_urb failed: %d\n", status);
        } else if (buf[0] != id) {
                status = -EIO;
        } else {
                memcpy(response_data, buf, status);
                *response_len = status;
                status = 0;
        }

        kfree(buf);
        return status;
}

static int iforce_usb_start_io(struct iforce *iforce)
{
        struct iforce_usb *iforce_usb = container_of(iforce, struct iforce_usb,
                                                     iforce);

        if (usb_submit_urb(iforce_usb->irq, GFP_KERNEL))
                return -EIO;

        return 0;
}

static void iforce_usb_stop_io(struct iforce *iforce)
{
        struct iforce_usb *iforce_usb = container_of(iforce, struct iforce_usb,
                                                     iforce);

        usb_kill_urb(iforce_usb->irq);
        usb_kill_urb(iforce_usb->out);
}

static const struct iforce_xport_ops iforce_usb_xport_ops = {
        .xmit           = iforce_usb_xmit,
        .get_id         = iforce_usb_get_id,
        .start_io       = iforce_usb_start_io,
        .stop_io        = iforce_usb_stop_io,
};

static void iforce_usb_irq(struct urb *urb)
{
        struct iforce_usb *iforce_usb = urb->context;
        struct iforce *iforce = &iforce_usb->iforce;
        struct device *dev = &iforce_usb->intf->dev;
        int status;

        switch (urb->status) {
        case 0:
                /* success */
                break;
        case -ECONNRESET:
        case -ENOENT:
        case -ESHUTDOWN:
                /* this urb is terminated, clean up */
                dev_dbg(dev, "%s - urb shutting down with status: %d\n",
                        __func__, urb->status);
                return;
        default:
                dev_dbg(dev, "%s - urb has status of: %d\n",
                        __func__, urb->status);
                goto exit;
        }

        iforce_process_packet(iforce, iforce_usb->data_in[0],
                              iforce_usb->data_in + 1, urb->actual_length - 1);

exit:
        status = usb_submit_urb(urb, GFP_ATOMIC);
        if (status)
                dev_err(dev, "%s - usb_submit_urb failed with result %d\n",
                        __func__, status);
}

static void iforce_usb_out(struct urb *urb)
{
        struct iforce_usb *iforce_usb = urb->context;
        struct iforce *iforce = &iforce_usb->iforce;

        if (urb->status) {
                dev_dbg(&iforce_usb->intf->dev, "urb->status %d, exiting\n",
                        urb->status);
                iforce_clear_xmit_and_wake(iforce);
                return;
        }

        __iforce_usb_xmit(iforce);

        wake_up_all(&iforce->wait);
}

static int iforce_usb_probe(struct usb_interface *intf,
                                const struct usb_device_id *id)
{
        struct usb_device *dev = interface_to_usbdev(intf);
        struct usb_host_interface *interface;
        struct usb_endpoint_descriptor *epirq, *epout;
        struct iforce_usb *iforce_usb;
        int err = -ENOMEM;

        interface = intf->cur_altsetting;

        if (interface->desc.bNumEndpoints < 2)
                return -ENODEV;

        epirq = &interface->endpoint[0].desc;
        if (!usb_endpoint_is_int_in(epirq))
                return -ENODEV;

        epout = &interface->endpoint[1].desc;
        if (!usb_endpoint_is_int_out(epout))
                return -ENODEV;

        iforce_usb = kzalloc_obj(*iforce_usb);
        if (!iforce_usb)
                goto fail;

        iforce_usb->irq = usb_alloc_urb(0, GFP_KERNEL);
        if (!iforce_usb->irq)
                goto fail;

        iforce_usb->out = usb_alloc_urb(0, GFP_KERNEL);
        if (!iforce_usb->out)
                goto fail;

        iforce_usb->iforce.xport_ops = &iforce_usb_xport_ops;

        iforce_usb->usbdev = dev;
        iforce_usb->intf = intf;

        usb_fill_int_urb(iforce_usb->irq, dev,
                         usb_rcvintpipe(dev, epirq->bEndpointAddress),
                         iforce_usb->data_in, sizeof(iforce_usb->data_in),
                         iforce_usb_irq, iforce_usb, epirq->bInterval);

        usb_fill_int_urb(iforce_usb->out, dev,
                         usb_sndintpipe(dev, epout->bEndpointAddress),
                         iforce_usb->data_out, sizeof(iforce_usb->data_out),
                         iforce_usb_out, iforce_usb, epout->bInterval);

        err = iforce_init_device(&intf->dev, BUS_USB, &iforce_usb->iforce);
        if (err)
                goto fail;

        usb_set_intfdata(intf, iforce_usb);
        return 0;

fail:
        if (iforce_usb) {
                usb_free_urb(iforce_usb->irq);
                usb_free_urb(iforce_usb->out);
                kfree(iforce_usb);
        }

        return err;
}

static void iforce_usb_disconnect(struct usb_interface *intf)
{
        struct iforce_usb *iforce_usb = usb_get_intfdata(intf);

        usb_set_intfdata(intf, NULL);

        input_unregister_device(iforce_usb->iforce.dev);

        usb_free_urb(iforce_usb->irq);
        usb_free_urb(iforce_usb->out);

        kfree(iforce_usb);
}

static const struct usb_device_id iforce_usb_ids[] = {
        { USB_DEVICE(0x044f, 0xa01c) },         /* Thrustmaster Motor Sport GT */
        { USB_DEVICE(0x046d, 0xc281) },         /* Logitech WingMan Force */
        { USB_DEVICE(0x046d, 0xc291) },         /* Logitech WingMan Formula Force */
        { USB_DEVICE(0x05ef, 0x020a) },         /* AVB Top Shot Pegasus */
        { USB_DEVICE(0x05ef, 0x8884) },         /* AVB Mag Turbo Force */
        { USB_DEVICE(0x05ef, 0x8888) },         /* AVB Top Shot FFB Racing Wheel */
        { USB_DEVICE(0x061c, 0xc0a4) },         /* ACT LABS Force RS */
        { USB_DEVICE(0x061c, 0xc084) },         /* ACT LABS Force RS */
        { USB_DEVICE(0x06a3, 0xff04) },         /* Saitek R440 Force Wheel */
        { USB_DEVICE(0x06f8, 0x0001) },         /* Guillemot Race Leader Force Feedback */
        { USB_DEVICE(0x06f8, 0x0003) },         /* Guillemot Jet Leader Force Feedback */
        { USB_DEVICE(0x06f8, 0x0004) },         /* Guillemot Force Feedback Racing Wheel */
        { USB_DEVICE(0x06f8, 0xa302) },         /* Guillemot Jet Leader 3D */
        { }                                     /* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, iforce_usb_ids);

struct usb_driver iforce_usb_driver = {
        .name =         "iforce",
        .probe =        iforce_usb_probe,
        .disconnect =   iforce_usb_disconnect,
        .id_table =     iforce_usb_ids,
};

module_usb_driver(iforce_usb_driver);

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>, Johann Deneux <johann.deneux@gmail.com>");
MODULE_DESCRIPTION("USB I-Force joysticks and wheels driver");
MODULE_LICENSE("GPL");