usb-serial.c

xen虚拟机源代码安装包

        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:
        s->lines = value & FTDI_MDM_CTRL;
        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:
        /* TODO: return modem status */
        data[0] = 0;
        ret = 1;
        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;
        }
        /* TODO: Report serial line status */
        *data++ = 0;
        *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);
}

int usb_serial_can_read(void *opaque)
{
    USBSerialState *s = opaque;
    return RECV_BUF - s->recv_used;
}

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;
}

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;

    while (*filename && *filename != ':') {
        const char *p;
        char *e;
        if (strstart(filename, "vendorid=", &p)) {
            vendorid = strtol(p, &e, 16);
            if (e == p || (*e && *e != ',' && *e != ':')) {
                printf("bogus vendor ID %s\n", p);
                return NULL;
            }
            filename = e;
        } else if (strstart(filename, "productid=", &p)) {
            productid = strtol(p, &e, 16);
            if (e == p || (*e && *e != ',' && *e != ':')) {
                printf("bogus product ID %s\n", p);
                return NULL;
            }
            filename = e;
        } else {
            printf("unrecognized serial USB option %s\n", filename);
            return NULL;
        }
        while(*filename == ',')
            filename++;
    }
    if (!*filename) {
        printf("character device specification needed\n");
        return NULL;
    }
    filename++;
    s = qemu_mallocz(sizeof(USBSerialState));
    if (!s)
        return NULL;

    cdrv = qemu_chr_open(filename);
    if (!cdrv)
        goto fail;
    s->cs = cdrv;
    qemu_chr_add_handlers(cdrv, usb_serial_can_read, usb_serial_read, usb_serial_event, s);

    s->dev.speed = USB_SPEED_FULL;
    s->dev.handle_packet = usb_generic_handle_packet;

    s->dev.handle_reset = usb_serial_handle_reset;
    s->dev.handle_control = usb_serial_handle_control;
    s->dev.handle_data = usb_serial_handle_data;
    s->dev.handle_destroy = usb_serial_handle_destroy;

    s->vendorid = vendorid;
    s->productid = productid;

    snprintf(s->dev.devname, sizeof(s->dev.devname), "QEMU USB Serial(%.16s)",
             filename);

    usb_serial_handle_reset((USBDevice *)s);
    return (USBDevice *)s;
 fail:
    qemu_free(s);
    return NULL;
}