/*

 * FTDI FT232BM Device emulation

 *

 * Copyright (c) 2006 CodeSourcery.

 * Copyright (c) 2008 Samuel Thibault <samuel.thibault@ens-lyon.org>

 * Written by Paul Brook, reused for FTDI by Samuel Thibault

 *

 * This code is licenced under the LGPL.

 */

#include "qemu-common.h"

#include "usb.h"

#include "qemu-char.h"

//#define DEBUG_Serial

#ifdef DEBUG_Serial

#define DPRINTF(fmt, args...) \

do { printf("usb-serial: " fmt , ##args); } while (0)

#else

#define DPRINTF(fmt, args...) do {} while(0)

#endif

#define RECV_BUF 384

/* Commands */

#define FTDI_RESET		0

#define FTDI_SET_MDM_CTRL	1

#define FTDI_SET_FLOW_CTRL	2

#define FTDI_SET_BAUD		3

#define FTDI_SET_DATA		4

#define FTDI_GET_MDM_ST		5

#define FTDI_SET_EVENT_CHR	6

#define FTDI_SET_ERROR_CHR	7

#define FTDI_SET_LATENCY	9

#define FTDI_GET_LATENCY	10

#define DeviceOutVendor	((USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)

#define DeviceInVendor	((USB_DIR_IN |USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)

/* RESET */

#define FTDI_RESET_SIO	0

#define FTDI_RESET_RX	1

#define FTDI_RESET_TX	2

/* SET_MDM_CTRL */

#define FTDI_DTR	1

#define FTDI_SET_DTR	(FTDI_DTR << 8)

#define FTDI_RTS	2

#define FTDI_SET_RTS	(FTDI_RTS << 8)

/* SET_FLOW_CTRL */

#define FTDI_RTS_CTS_HS		1

#define FTDI_DTR_DSR_HS		2

#define FTDI_XON_XOFF_HS	4

/* SET_DATA */

#define FTDI_PARITY	(0x7 << 8)

#define FTDI_ODD	(0x1 << 8)

#define FTDI_EVEN	(0x2 << 8)

#define FTDI_MARK	(0x3 << 8)

#define FTDI_SPACE	(0x4 << 8)

#define FTDI_STOP	(0x3 << 11)

#define FTDI_STOP1	(0x0 << 11)

#define FTDI_STOP15	(0x1 << 11)

#define FTDI_STOP2	(0x2 << 11)

/* GET_MDM_ST */

/* TODO: should be sent every 40ms */

#define FTDI_CTS  (1<<4)        // CTS line status

#define FTDI_DSR  (1<<5)        // DSR line status

#define FTDI_RI   (1<<6)        // RI line status

#define FTDI_RLSD (1<<7)        // Receive Line Signal Detect

/* Status */

#define FTDI_DR   (1<<0)        // Data Ready

#define FTDI_OE   (1<<1)        // Overrun Err

#define FTDI_PE   (1<<2)        // Parity Err

#define FTDI_FE   (1<<3)        // Framing Err

#define FTDI_BI   (1<<4)        // Break Interrupt

#define FTDI_THRE (1<<5)        // Transmitter Holding Register

#define FTDI_TEMT (1<<6)        // Transmitter Empty

#define FTDI_FIFO (1<<7)        // Error in FIFO

typedef struct {

    USBDevice dev;

    uint16_t vendorid;

    uint16_t productid;

    uint8_t recv_buf[RECV_BUF];

    uint16_t recv_ptr;

    uint16_t recv_used;

    uint8_t event_chr;

    uint8_t error_chr;

    uint8_t event_trigger;

    QEMUSerialSetParams params;

    int latency;        /* ms */

    CharDriverState *cs;

} USBSerialState;

static const uint8_t qemu_serial_dev_descriptor[] = {

        0x12,       /*  u8 bLength; */

        0x01,       /*  u8 bDescriptorType; Device */

        0x00, 0x02, /*  u16 bcdUSB; v2.0 */

        0x00,       /*  u8  bDeviceClass; */

        0x00,       /*  u8  bDeviceSubClass; */

        0x00,       /*  u8  bDeviceProtocol; [ low/full speeds only ] */

        0x08,       /*  u8  bMaxPacketSize0; 8 Bytes */

        /* Vendor and product id are arbitrary.  */

        0x03, 0x04, /*  u16 idVendor; */

        0x00, 0xFF, /*  u16 idProduct; */

        0x00, 0x04, /*  u16 bcdDevice */

        0x01,       /*  u8  iManufacturer; */

        0x02,       /*  u8  iProduct; */

        0x03,       /*  u8  iSerialNumber; */

        0x01        /*  u8  bNumConfigurations; */

};

static const uint8_t qemu_serial_config_descriptor[] = {

        /* one configuration */

        0x09,       /*  u8  bLength; */

        0x02,       /*  u8  bDescriptorType; Configuration */

        0x20, 0x00, /*  u16 wTotalLength; */

        0x01,       /*  u8  bNumInterfaces; (1) */

        0x01,       /*  u8  bConfigurationValue; */

        0x00,       /*  u8  iConfiguration; */

        0x80,       /*  u8  bmAttributes;

                                 Bit 7: must be set,

                                     6: Self-powered,

                                     5: Remote wakeup,

                                     4..0: resvd */

        100/2,       /*  u8  MaxPower; */

        /* one interface */

        0x09,       /*  u8  if_bLength; */

        0x04,       /*  u8  if_bDescriptorType; Interface */

        0x00,       /*  u8  if_bInterfaceNumber; */

        0x00,       /*  u8  if_bAlternateSetting; */

        0x02,       /*  u8  if_bNumEndpoints; */

        0xff,       /*  u8  if_bInterfaceClass; Vendor Specific */

        0xff,       /*  u8  if_bInterfaceSubClass; Vendor Specific */

        0xff,       /*  u8  if_bInterfaceProtocol; Vendor Specific */

        0x02,       /*  u8  if_iInterface; */

        /* Bulk-In endpoint */

        0x07,       /*  u8  ep_bLength; */

        0x05,       /*  u8  ep_bDescriptorType; Endpoint */

        0x81,       /*  u8  ep_bEndpointAddress; IN Endpoint 1 */

        0x02,       /*  u8  ep_bmAttributes; Bulk */

        0x40, 0x00, /*  u16 ep_wMaxPacketSize; */

        0x00,       /*  u8  ep_bInterval; */

        /* Bulk-Out endpoint */

        0x07,       /*  u8  ep_bLength; */

        0x05,       /*  u8  ep_bDescriptorType; Endpoint */

        0x02,       /*  u8  ep_bEndpointAddress; OUT Endpoint 2 */

        0x02,       /*  u8  ep_bmAttributes; Bulk */

        0x40, 0x00, /*  u16 ep_wMaxPacketSize; */

        0x00        /*  u8  ep_bInterval; */

};

static void usb_serial_reset(USBSerialState *s)

{

    /* TODO: Set flow control to none */

    s->event_chr = 0x0d;

    s->event_trigger = 0;

    s->recv_ptr = 0;

    s->recv_used = 0;

    /* TODO: purge in char driver */

}

static void usb_serial_handle_reset(USBDevice *dev)

{

    USBSerialState *s = (USBSerialState *)dev;

    DPRINTF("Reset\n");

    usb_serial_reset(s);

    /* TODO: Reset char device, send BREAK? */

}

static uint8_t usb_get_modem_lines(USBSerialState *s)

{

    int flags;

    uint8_t ret;

    if (qemu_chr_ioctl(s->cs, CHR_IOCTL_SERIAL_GET_TIOCM, &flags) == -ENOTSUP)

        return FTDI_CTS|FTDI_DSR|FTDI_RLSD;

    ret = 0;

    if (flags & CHR_TIOCM_CTS)

        ret |= FTDI_CTS;

    if (flags & CHR_TIOCM_DSR)

        ret |= FTDI_DSR;

    if (flags & CHR_TIOCM_RI)

        ret |= FTDI_RI;

    if (flags & CHR_TIOCM_CAR)

        ret |= FTDI_RLSD;

    return ret;

}

static int usb_serial_handle_control(USBDevice *dev, int request, int value,

                                  int index, int length, uint8_t *data)

{

    USBSerialState *s = (USBSerialState *)dev;

    int ret = 0;

    //DPRINTF("got control %x, value %x\n",request, value);

    switch (request) {

    case DeviceRequest | USB_REQ_GET_STATUS:

        data[0] = (0 << USB_DEVICE_SELF_POWERED) |

            (dev->remote_wakeup << USB_DEVICE_REMOTE_WAKEUP);

        data[1] = 0x00;

        ret = 2;

        break;

    case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:

        if (value == USB_DEVICE_REMOTE_WAKEUP) {

            dev->remote_wakeup = 0;

        } else {

            goto fail;

        }

        ret = 0;

        break;

    case DeviceOutRequest | USB_REQ_SET_FEATURE:

        if (value == USB_DEVICE_REMOTE_WAKEUP) {

            dev->remote_wakeup = 1;

        } else {

            goto fail;

        }

        ret = 0;

        break;

    case DeviceOutRequest | USB_REQ_SET_ADDRESS:

        dev->addr = value;

        ret = 0;

        break;

    case DeviceRequest | USB_REQ_GET_DESCRIPTOR:

        switch(value >> 8) {

        case USB_DT_DEVICE:

            memcpy(data, qemu_serial_dev_descriptor,

                   sizeof(qemu_serial_dev_descriptor));

            data[8] = s->vendorid & 0xff;

            data[9] = ((s->vendorid) >> 8) & 0xff;

            data[10] = s->productid & 0xff;

            data[11] = ((s->productid) >> 8) & 0xff;

            ret = sizeof(qemu_serial_dev_descriptor);

            break;

        case USB_DT_CONFIG:

            memcpy(data, qemu_serial_config_descriptor,

                   sizeof(qemu_serial_config_descriptor));

            ret = sizeof(qemu_serial_config_descriptor);

            break;

        case USB_DT_STRING:

            switch(value & 0xff) {

            case 0:

                /* language ids */

                data[0] = 4;

                data[1] = 3;

                data[2] = 0x09;

                data[3] = 0x04;

                ret = 4;

                break;

            case 1:

                /* vendor description */

                ret = set_usb_string(data, "QEMU " QEMU_VERSION);

                break;

            case 2:

                /* product description */

                ret = set_usb_string(data, "QEMU USB SERIAL");

                break;

            case 3:

                /* serial number */

                ret = set_usb_string(data, "1");

                break;

            default:

                goto fail;

            }

            break;

        default:

            goto fail;

        }

        break;

    case DeviceRequest | USB_REQ_GET_CONFIGURATION:

        data[0] = 1;

        ret = 1;

        break;

    case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:

        ret = 0;

        break;

    case DeviceRequest | USB_REQ_GET_INTERFACE:

        data[0] = 0;

        ret = 1;

        break;

    case InterfaceOutRequest | USB_REQ_SET_INTERFACE:

        ret = 0;

        break;

    case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:

        ret = 0;

        break;

        /* Class specific requests.  */

    case DeviceOutVendor | FTDI_RESET:

        switch (value) {

        case FTDI_RESET_SIO:

            usb_serial_reset(s);

            break;

        case FTDI_RESET_RX:

            s->recv_ptr = 0;

            s->recv_used = 0;

            /* TODO: purge from char device */

            break;

        case FTDI_RESET_TX:

            /* TODO: purge from char device */

            break;

        }

        break;

    case DeviceOutVendor | FTDI_SET_MDM_CTRL:

    {

        static int flags;

        qemu_chr_ioctl(s->cs,CHR_IOCTL_SERIAL_GET_TIOCM, &flags);

        if (value & FTDI_SET_RTS) {

            if (value & FTDI_RTS)

                flags |= CHR_TIOCM_RTS;

            else

                flags &= ~CHR_TIOCM_RTS;

        }

        if (value & FTDI_SET_DTR) {

            if (value & FTDI_DTR)

                flags |= CHR_TIOCM_DTR;

            else

                flags &= ~CHR_TIOCM_DTR;

        }

        qemu_chr_ioctl(s->cs,CHR_IOCTL_SERIAL_SET_TIOCM, &flags);

        break;

    }

    case DeviceOutVendor | FTDI_SET_FLOW_CTRL:

        /* TODO: ioctl */

        break;

    case DeviceOutVendor | FTDI_SET_BAUD: {

        static const int subdivisors8[8] = { 0, 4, 2, 1, 3, 5, 6, 7 };

        int subdivisor8 = subdivisors8[((value & 0xc000) >> 14)

                                     | ((index & 1) << 2)];

        int divisor = value & 0x3fff;

        /* chip special cases */

        if (divisor == 1 && subdivisor8 == 0)

            subdivisor8 = 4;

        if (divisor == 0 && subdivisor8 == 0)

            divisor = 1;

        s->params.speed = (48000000 / 2) / (8 * divisor + subdivisor8);

        qemu_chr_ioctl(s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);

        break;

    }

    case DeviceOutVendor | FTDI_SET_DATA:

        switch (value & FTDI_PARITY) {

            case 0:

                s->params.parity = 'N';

                break;

            case FTDI_ODD:

                s->params.parity = 'O';

                break;

            case FTDI_EVEN:

                s->params.parity = 'E';

                break;

            default:

                DPRINTF("unsupported parity %d\n", value & FTDI_PARITY);

                goto fail;

        }

        switch (value & FTDI_STOP) {

            case FTDI_STOP1:

                s->params.stop_bits = 1;

                break;

            case FTDI_STOP2:

                s->params.stop_bits = 2;

                break;

            default:

                DPRINTF("unsupported stop bits %d\n", value & FTDI_STOP);

                goto fail;

        }

        qemu_chr_ioctl(s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);

        /* TODO: TX ON/OFF */

        break;

    case DeviceInVendor | FTDI_GET_MDM_ST:

        data[0] = usb_get_modem_lines(s) | 1;

        data[1] = 0;

        ret = 2;

        break;

    case DeviceOutVendor | FTDI_SET_EVENT_CHR:

        /* TODO: handle it */

        s->event_chr = value;

        break;

    case DeviceOutVendor | FTDI_SET_ERROR_CHR:

        /* TODO: handle it */

        s->error_chr = value;

        break;

    case DeviceOutVendor | FTDI_SET_LATENCY:

        s->latency = value;

        break;

    case DeviceInVendor | FTDI_GET_LATENCY:

        data[0] = s->latency;

        ret = 1;

        break;

    default:

    fail:

        DPRINTF("got unsupported/bogus control %x, value %x\n", request, value);

        ret = USB_RET_STALL;

        break;

    }

    return ret;

}

static int usb_serial_handle_data(USBDevice *dev, USBPacket *p)

{

    USBSerialState *s = (USBSerialState *)dev;

    int ret = 0;

    uint8_t devep = p->devep;

    uint8_t *data = p->data;

    int len = p->len;

    int first_len;

    switch (p->pid) {

    case USB_TOKEN_OUT:

        if (devep != 2)

            goto fail;

        qemu_chr_write(s->cs, data, len);

        break;

    case USB_TOKEN_IN:

        if (devep != 1)

            goto fail;

        first_len = RECV_BUF - s->recv_ptr;

        if (len <= 2) {

            ret = USB_RET_NAK;

            break;

        }

        *data++ = usb_get_modem_lines(s) | 1;

        /* We do not have the uart details */

        *data++ = 0;

        len -= 2;

        if (len > s->recv_used)

            len = s->recv_used;

        if (!len) {

            ret = USB_RET_NAK;

            break;

        }

        if (first_len > len)

            first_len = len;

        memcpy(data, s->recv_buf + s->recv_ptr, first_len);

        if (len > first_len)

            memcpy(data + first_len, s->recv_buf, len - first_len);

        s->recv_used -= len;

        s->recv_ptr = (s->recv_ptr + len) % RECV_BUF;

        ret = len + 2;

        break;

    default:

        DPRINTF("Bad token\n");

    fail:

        ret = USB_RET_STALL;

        break;

    }

    return ret;

}

static void usb_serial_handle_destroy(USBDevice *dev)

{

    USBSerialState *s = (USBSerialState *)dev;

    qemu_chr_close(s->cs);

    qemu_free(s);

}

static int usb_serial_can_read(void *opaque)

{

    USBSerialState *s = opaque;

    return RECV_BUF - s->recv_used;

}

static void usb_serial_read(void *opaque, const uint8_t *buf, int size)

{

    USBSerialState *s = opaque;

    int first_size = RECV_BUF - s->recv_ptr;

    if (first_size > size)

        first_size = size;

    memcpy(s->recv_buf + s->recv_ptr + s->recv_used, buf, first_size);

    if (size > first_size)

        memcpy(s->recv_buf, buf + first_size, size - first_size);

    s->recv_used += size;

}

static void usb_serial_event(void *opaque, int event)

{

    USBSerialState *s = opaque;

    switch (event) {

        case CHR_EVENT_BREAK:

            /* TODO: Send Break to USB */

            break;

        case CHR_EVENT_FOCUS:

            break;

        case CHR_EVENT_RESET:

            usb_serial_reset(s);

            /* TODO: Reset USB port */

            break;

    }

}

USBDevice *usb_serial_init(const char *filename)

{

    USBSerialState *s;

    CharDriverState *cdrv;

    unsigned short vendorid = 0x0403, productid = 0x6001;

    char label[32];

    static int index;

    while (*filename && *filename != ':') {

        const char *p;