Commit 1b4b29a1 authored by Gerd Hoffmann's avatar Gerd Hoffmann
Browse files

usb: add shortcut for control transfers 



Add a more direct code path to submit control transfers.  Instead of
feeding three usb packets (setup, data, ack) to usb_handle_packet and
have the do_token_* functions in usb.c poke the control transfer
parameters out of it just submit a single packet carrying the actual
data with the control xfer parameters filled into USBPacket->parameters.

Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
parent 9424d4e7

hw/usb.c

+59 −0
Original line number Diff line number Diff line
@@ -95,6 +95,7 @@ void usb_wakeup(USBEndpoint *ep) 
#define SETUP_STATE_SETUP 1

#define SETUP_STATE_DATA  2

#define SETUP_STATE_ACK   3

#define SETUP_STATE_PARAM 4



static int do_token_setup(USBDevice *s, USBPacket *p)

{
@@ -226,6 +227,50 @@ static int do_token_out(USBDevice *s, USBPacket *p) 
    }

}



static int do_parameter(USBDevice *s, USBPacket *p)

{

    int request, value, index;

    int i, ret = 0;



    for (i = 0; i < 8; i++) {

        s->setup_buf[i] = p->parameter >> (i*8);

    }



    s->setup_state = SETUP_STATE_PARAM;

    s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];

    s->setup_index = 0;



    request = (s->setup_buf[0] << 8) | s->setup_buf[1];

    value   = (s->setup_buf[3] << 8) | s->setup_buf[2];

    index   = (s->setup_buf[5] << 8) | s->setup_buf[4];



    if (s->setup_len > sizeof(s->data_buf)) {

        fprintf(stderr,

                "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",

                s->setup_len, sizeof(s->data_buf));

        return USB_RET_STALL;

    }



    if (p->pid == USB_TOKEN_OUT) {

        usb_packet_copy(p, s->data_buf, s->setup_len);

    }



    ret = usb_device_handle_control(s, p, request, value, index,

                                    s->setup_len, s->data_buf);

    if (ret < 0) {

        return ret;

    }



    if (ret < s->setup_len) {

        s->setup_len = ret;

    }

    if (p->pid == USB_TOKEN_IN) {

        usb_packet_copy(p, s->data_buf, s->setup_len);

    }



    return ret;

}



/* ctrl complete function for devices which use usb_generic_handle_packet and

   may return USB_RET_ASYNC from their handle_control callback. Device code

   which does this *must* call this function instead of the normal
@@ -250,6 +295,16 @@ void usb_generic_async_ctrl_complete(USBDevice *s, USBPacket *p) 
        p->result = 0;

        break;



    case SETUP_STATE_PARAM:

        if (p->result < s->setup_len) {

            s->setup_len = p->result;

        }

        if (p->pid == USB_TOKEN_IN) {

            p->result = 0;

            usb_packet_copy(p, s->data_buf, s->setup_len);

        }

        break;



    default:

        break;

    }
@@ -292,6 +347,9 @@ static int usb_process_one(USBPacket *p) 


    if (p->ep->nr == 0) {

        /* control pipe */

        if (p->parameter) {

            return do_parameter(dev, p);

        }

        switch (p->pid) {

        case USB_TOKEN_SETUP:

            return do_token_setup(dev, p);
@@ -416,6 +474,7 @@ void usb_packet_setup(USBPacket *p, int pid, USBEndpoint *ep) 
    p->pid = pid;

    p->ep = ep;

    p->result = 0;

    p->parameter = 0;

    qemu_iovec_reset(&p->iov);

    usb_packet_set_state(p, USB_PACKET_SETUP);

}

hw/usb.h

+1 −0
Original line number Diff line number Diff line
@@ -327,6 +327,7 @@ struct USBPacket { 
    int pid;

    USBEndpoint *ep;

    QEMUIOVector iov;

    uint64_t parameter; /* control transfers */

    int result; /* transfer length or USB_RET_* status code */

    /* Internal use by the USB layer.  */

    USBPacketState state;