/*

 * Linux host USB redirector

 *

 * Copyright (c) 2005 Fabrice Bellard

 *

 * Copyright (c) 2008 Max Krasnyansky

 *      Support for host device auto connect & disconnect

 *      Major rewrite to support fully async operation

 *

 * Copyright 2008 TJ <linux@tjworld.net>

 *      Added flexible support for /dev/bus/usb /sys/bus/usb/devices in addition

 *      to the legacy /proc/bus/usb USB device discovery and handling

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "qemu-common.h"

#include "qemu-timer.h"

#include "console.h"

#include <dirent.h>

#include <sys/ioctl.h>

#include <signal.h>

#include <linux/usbdevice_fs.h>

#include <linux/version.h>

#include "hw/usb.h"

/* We redefine it to avoid version problems */

struct usb_ctrltransfer {

    uint8_t  bRequestType;

    uint8_t  bRequest;

    uint16_t wValue;

    uint16_t wIndex;

    uint16_t wLength;

    uint32_t timeout;

    void *data;

};

struct usb_ctrlrequest {

    uint8_t bRequestType;

    uint8_t bRequest;

    uint16_t wValue;

    uint16_t wIndex;

    uint16_t wLength;

};

typedef int USBScanFunc(void *opaque, int bus_num, int addr, int class_id,

                        int vendor_id, int product_id,

                        const char *product_name, int speed);

static int usb_host_find_device(int *pbus_num, int *paddr,

                                char *product_name, int product_name_size,

                                const char *devname);

//#define DEBUG

#ifdef DEBUG

#define dprintf printf

#else

#define dprintf(...)

#endif

#define USBDBG_DEVOPENED "husb: opened %s/devices\n"

#define USBPROCBUS_PATH "/proc/bus/usb"

#define PRODUCT_NAME_SZ 32

#define MAX_ENDPOINTS 16

#define USBDEVBUS_PATH "/dev/bus/usb"

#define USBSYSBUS_PATH "/sys/bus/usb"

static char *usb_host_device_path;

#define USB_FS_NONE 0

#define USB_FS_PROC 1

#define USB_FS_DEV 2

#define USB_FS_SYS 3

static int usb_fs_type;

/* endpoint association data */

struct endp_data {

    uint8_t type;

    uint8_t halted;

};

enum {

    CTRL_STATE_IDLE = 0,

    CTRL_STATE_SETUP,

    CTRL_STATE_DATA,

    CTRL_STATE_ACK

};

/*

 * Control transfer state.

 * Note that 'buffer' _must_ follow 'req' field because 

 * we need contigious buffer when we submit control URB.

 */ 

struct ctrl_struct {

    uint16_t len;

    uint16_t offset;

    uint8_t  state;

    struct   usb_ctrlrequest req;

    uint8_t  buffer[1024];

};

typedef struct USBHostDevice {

    USBDevice dev;

    int       fd;

    uint8_t   descr[1024];

    int       descr_len;

    int       configuration;

    int       ninterfaces;

    int       closing;

    struct ctrl_struct ctrl;

    struct endp_data endp_table[MAX_ENDPOINTS];

    /* Host side address */

    int bus_num;

    int addr;

    struct USBHostDevice *next;

} USBHostDevice;

static int is_isoc(USBHostDevice *s, int ep)

{

    return s->endp_table[ep - 1].type == USBDEVFS_URB_TYPE_ISO;

}

static int is_halted(USBHostDevice *s, int ep)

{

    return s->endp_table[ep - 1].halted;

}

static void clear_halt(USBHostDevice *s, int ep)

{

    s->endp_table[ep - 1].halted = 0;

}

static void set_halt(USBHostDevice *s, int ep)

{

    s->endp_table[ep - 1].halted = 1;

}

static USBHostDevice *hostdev_list;

static void hostdev_link(USBHostDevice *dev)

{

    dev->next = hostdev_list;

    hostdev_list = dev;

}

static void hostdev_unlink(USBHostDevice *dev)

{

    USBHostDevice *pdev = hostdev_list;

    USBHostDevice **prev = &hostdev_list;

    while (pdev) {

	if (pdev == dev) {

            *prev = dev->next;

            return;

        }

        prev = &pdev->next;

        pdev = pdev->next;

    }

}

static USBHostDevice *hostdev_find(int bus_num, int addr)

{

    USBHostDevice *s = hostdev_list;

    while (s) {

        if (s->bus_num == bus_num && s->addr == addr)

            return s;

        s = s->next;

    }

    return NULL;

}

/* 

 * Async URB state.

 * We always allocate one isoc descriptor even for bulk transfers

 * to simplify allocation and casts. 

 */

typedef struct AsyncURB

{

    struct usbdevfs_urb urb;

    struct usbdevfs_iso_packet_desc isocpd;

    USBPacket     *packet;

    USBHostDevice *hdev;

} AsyncURB;

static AsyncURB *async_alloc(void)

{

    return (AsyncURB *) qemu_mallocz(sizeof(AsyncURB));

}

static void async_free(AsyncURB *aurb)

{

    qemu_free(aurb);

}

static void async_complete_ctrl(USBHostDevice *s, USBPacket *p)

{

    switch(s->ctrl.state) {

    case CTRL_STATE_SETUP:

        if (p->len < s->ctrl.len)

            s->ctrl.len = p->len;

        s->ctrl.state = CTRL_STATE_DATA;

        p->len = 8;

        break;

    case CTRL_STATE_ACK:

        s->ctrl.state = CTRL_STATE_IDLE;

        p->len = 0;

        break;

    default:

        break;

    }

}

static void async_complete(void *opaque)

{

    USBHostDevice *s = opaque;

    AsyncURB *aurb;

    while (1) {

    	USBPacket *p;

	int r = ioctl(s->fd, USBDEVFS_REAPURBNDELAY, &aurb);

        if (r < 0) {

            if (errno == EAGAIN)

                return;

            if (errno == ENODEV && !s->closing) {

                printf("husb: device %d.%d disconnected\n", s->bus_num, s->addr);

	        usb_device_del_addr(0, s->dev.addr);

                return;

            }

            dprintf("husb: async. reap urb failed errno %d\n", errno);

            return;

        }

        p = aurb->packet;

	dprintf("husb: async completed. aurb %p status %d alen %d\n", 

                aurb, aurb->urb.status, aurb->urb.actual_length);

	if (p) {

            switch (aurb->urb.status) {

            case 0:

                p->len = aurb->urb.actual_length;

                if (aurb->urb.type == USBDEVFS_URB_TYPE_CONTROL)

                    async_complete_ctrl(s, p);

                break;

            case -EPIPE:

                set_halt(s, p->devep);

                /* fall through */

            default:

                p->len = USB_RET_NAK;

                break;

            }

            usb_packet_complete(p);

	}

        async_free(aurb);

    }

}

static void async_cancel(USBPacket *unused, void *opaque)

{

    AsyncURB *aurb = opaque;

    USBHostDevice *s = aurb->hdev;

    dprintf("husb: async cancel. aurb %p\n", aurb);

    /* Mark it as dead (see async_complete above) */

    aurb->packet = NULL;

    int r = ioctl(s->fd, USBDEVFS_DISCARDURB, aurb);

    if (r < 0) {

        dprintf("husb: async. discard urb failed errno %d\n", errno);

    }

}

static int usb_host_claim_interfaces(USBHostDevice *dev, int configuration)

{

    int dev_descr_len, config_descr_len;

    int interface, nb_interfaces, nb_configurations;

    int ret, i;

    if (configuration == 0) /* address state - ignore */

        return 1;

    dprintf("husb: claiming interfaces. config %d\n", configuration);

    i = 0;

    dev_descr_len = dev->descr[0];

    if (dev_descr_len > dev->descr_len)

        goto fail;

    nb_configurations = dev->descr[17];

    i += dev_descr_len;

    while (i < dev->descr_len) {

        dprintf("husb: i is %d, descr_len is %d, dl %d, dt %d\n", i, dev->descr_len,

               dev->descr[i], dev->descr[i+1]);

        if (dev->descr[i+1] != USB_DT_CONFIG) {

            i += dev->descr[i];

            continue;

        }

        config_descr_len = dev->descr[i];

	printf("husb: config #%d need %d\n", dev->descr[i + 5], configuration); 

        if (configuration < 0 || configuration == dev->descr[i + 5]) {

            configuration = dev->descr[i + 5];

            break;

        }

        i += config_descr_len;

    }

    if (i >= dev->descr_len) {

        fprintf(stderr, "husb: update iface failed. no matching configuration\n");

        goto fail;

    }

    nb_interfaces = dev->descr[i + 4];

#ifdef USBDEVFS_DISCONNECT

    /* earlier Linux 2.4 do not support that */

    {

        struct usbdevfs_ioctl ctrl;

        for (interface = 0; interface < nb_interfaces; interface++) {

            ctrl.ioctl_code = USBDEVFS_DISCONNECT;

            ctrl.ifno = interface;

            ret = ioctl(dev->fd, USBDEVFS_IOCTL, &ctrl);

            if (ret < 0 && errno != ENODATA) {

                perror("USBDEVFS_DISCONNECT");

                goto fail;

            }

        }

    }

#endif

    /* XXX: only grab if all interfaces are free */

    for (interface = 0; interface < nb_interfaces; interface++) {

        ret = ioctl(dev->fd, USBDEVFS_CLAIMINTERFACE, &interface);

        if (ret < 0) {

            if (errno == EBUSY) {

                printf("husb: update iface. device already grabbed\n");

            } else {

                perror("husb: failed to claim interface");

            }

        fail:

            return 0;

        }

    }

    printf("husb: %d interfaces claimed for configuration %d\n",

           nb_interfaces, configuration);

    dev->ninterfaces   = nb_interfaces;

    dev->configuration = configuration;

    return 1;

}

static int usb_host_release_interfaces(USBHostDevice *s)

{

    int ret, i;

    dprintf("husb: releasing interfaces\n");

    for (i = 0; i < s->ninterfaces; i++) {

        ret = ioctl(s->fd, USBDEVFS_RELEASEINTERFACE, &i);

        if (ret < 0) {

            perror("husb: failed to release interface");

            return 0;

        }

    }

    return 1;

}

static void usb_host_handle_reset(USBDevice *dev)

{

    USBHostDevice *s = (USBHostDevice *) dev;

    dprintf("husb: reset device %u.%u\n", s->bus_num, s->addr);

    ioctl(s->fd, USBDEVFS_RESET);

    usb_host_claim_interfaces(s, s->configuration);

}

static void usb_host_handle_destroy(USBDevice *dev)

{

    USBHostDevice *s = (USBHostDevice *)dev;

    s->closing = 1;

    qemu_set_fd_handler(s->fd, NULL, NULL, NULL);

    hostdev_unlink(s);

    async_complete(s);

    if (s->fd >= 0)

        close(s->fd);

    qemu_free(s);

}

static int usb_linux_update_endp_table(USBHostDevice *s);

static int usb_host_handle_data(USBHostDevice *s, USBPacket *p)

{

    struct usbdevfs_urb *urb;

    AsyncURB *aurb;

    int ret;

    aurb = async_alloc();

    if (!aurb) {

        dprintf("husb: async malloc failed\n");

        return USB_RET_NAK;

    }

    aurb->hdev   = s;

    aurb->packet = p;

    urb = &aurb->urb;

    if (p->pid == USB_TOKEN_IN)

    	urb->endpoint = p->devep | 0x80;

    else

    	urb->endpoint = p->devep;

    if (is_halted(s, p->devep)) {

	ret = ioctl(s->fd, USBDEVFS_CLEAR_HALT, &urb->endpoint);

        if (ret < 0) {

            dprintf("husb: failed to clear halt. ep 0x%x errno %d\n", 

                   urb->endpoint, errno);

            return USB_RET_NAK;

        }

        clear_halt(s, p->devep);

    }

    urb->buffer        = p->data;

    urb->buffer_length = p->len;

    if (is_isoc(s, p->devep)) {

        /* Setup ISOC transfer */

        urb->type     = USBDEVFS_URB_TYPE_ISO;

        urb->flags    = USBDEVFS_URB_ISO_ASAP;

        urb->number_of_packets = 1;

        urb->iso_frame_desc[0].length = p->len;

    } else {

        /* Setup bulk transfer */

        urb->type     = USBDEVFS_URB_TYPE_BULK;

    }

    urb->usercontext = s;

    ret = ioctl(s->fd, USBDEVFS_SUBMITURB, urb);

    dprintf("husb: data submit. ep 0x%x len %u aurb %p\n", urb->endpoint, p->len, aurb);

    if (ret < 0) {

        dprintf("husb: submit failed. errno %d\n", errno);

        async_free(aurb);

        switch(errno) {

        case ETIMEDOUT:

            return USB_RET_NAK;

        case EPIPE:

        default:

            return USB_RET_STALL;

        }

    }

    usb_defer_packet(p, async_cancel, aurb);

    return USB_RET_ASYNC;

}

static int ctrl_error(void)

{

    if (errno == ETIMEDOUT)

        return USB_RET_NAK;

    else 

        return USB_RET_STALL;

}

static int usb_host_set_address(USBHostDevice *s, int addr)

{

    dprintf("husb: ctrl set addr %u\n", addr);

    s->dev.addr = addr;

    return 0;

}

static int usb_host_set_config(USBHostDevice *s, int config)

{

    usb_host_release_interfaces(s);

    int ret = ioctl(s->fd, USBDEVFS_SETCONFIGURATION, &config);

    dprintf("husb: ctrl set config %d ret %d errno %d\n", config, ret, errno);

    if (ret < 0)

        return ctrl_error();