usb-urb.c

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/* usb-urb.c is part of the DVB USB library.
 *
 * Copyright (C) 2004-6 Patrick Boettcher ([email protected])
 * see dvb-usb-init.c for copyright information.
 *
 * This file keeps functions for initializing and handling the
 * BULK and ISOC USB data transfers in a generic way.
 * Can be used for DVB-only and also, that's the plan, for
 * Hybrid USB devices (analog and DVB).
 */
#include "dvb-usb-common.h"

/* URB stuff for streaming */
static void usb_urb_complete(struct urb *urb)
{
    struct usb_data_stream *stream = urb->context;
    int ptype = usb_pipetype(urb->pipe);
    int i;
    u8 *b;

    deb_uxfer("'%s' urb completed. status: %d, length: %d/%d, pack_num: %d, errors: %d\n",
        ptype == PIPE_ISOCHRONOUS ? "isoc" : "bulk",
        urb->status,urb->actual_length,urb->transfer_buffer_length,
        urb->number_of_packets,urb->error_count);

    switch (urb->status) {
        case 0:         /* success */
        case -ETIMEDOUT:    /* NAK */
            break;
        case -ECONNRESET:   /* kill */
        case -ENOENT:
        case -ESHUTDOWN:
            return;
        default:        /* error */
            deb_ts("urb completition error %d.\n", urb->status);
            break;
    }

    b = (u8 *) urb->transfer_buffer;
    switch (ptype) {
        case PIPE_ISOCHRONOUS:
            for (i = 0; i < urb->number_of_packets; i++) {

                if (urb->iso_frame_desc[i].status != 0)
                    deb_ts("iso frame descriptor has an error: %d\n",urb->iso_frame_desc[i].status);
                else if (urb->iso_frame_desc[i].actual_length > 0)
                    stream->complete(stream, b + urb->iso_frame_desc[i].offset, urb->iso_frame_desc[i].actual_length);

                urb->iso_frame_desc[i].status = 0;
                urb->iso_frame_desc[i].actual_length = 0;
            }
            debug_dump(b,20,deb_uxfer);
            break;
        case PIPE_BULK:
            if (urb->actual_length > 0)
                stream->complete(stream, b, urb->actual_length);
            break;
        default:
            err("unknown endpoint type in completition handler.");
            return;
    }
    usb_submit_urb(urb,GFP_ATOMIC);
}

int usb_urb_kill(struct usb_data_stream *stream)
{
    int i;
    for (i = 0; i < stream->urbs_submitted; i++) {
        deb_ts("killing URB no. %d.\n",i);

        /* stop the URB */
        usb_kill_urb(stream->urb_list[i]);
    }
    stream->urbs_submitted = 0;
    return 0;
}

int usb_urb_submit(struct usb_data_stream *stream)
{
    int i,ret;
    for (i = 0; i < stream->urbs_initialized; i++) {
        deb_ts("submitting URB no. %d\n",i);
        if ((ret = usb_submit_urb(stream->urb_list[i],GFP_ATOMIC))) {
            err("could not submit URB no. %d - get them all back",i);
            usb_urb_kill(stream);
            return ret;
        }
        stream->urbs_submitted++;
    }
    return 0;
}

static int usb_free_stream_buffers(struct usb_data_stream *stream)
{
    if (stream->state & USB_STATE_URB_BUF) {
        while (stream->buf_num) {
            stream->buf_num--;
            deb_mem("freeing buffer %d\n",stream->buf_num);
            usb_free_coherent(stream->udev, stream->buf_size,
                      stream->buf_list[stream->buf_num],
                      stream->dma_addr[stream->buf_num]);
        }
    }

    stream->state &= ~USB_STATE_URB_BUF;

    return 0;
}

static int usb_allocate_stream_buffers(struct usb_data_stream *stream, int num, unsigned long size)
{
    stream->buf_num = 0;
    stream->buf_size = size;

    deb_mem("all in all I will use %lu bytes for streaming\n",num*size);

    for (stream->buf_num = 0; stream->buf_num < num; stream->buf_num++) {
        deb_mem("allocating buffer %d\n",stream->buf_num);
        if (( stream->buf_list[stream->buf_num] =
                    usb_alloc_coherent(stream->udev, size, GFP_ATOMIC,
                    &stream->dma_addr[stream->buf_num]) ) == NULL) {
            deb_mem("not enough memory for urb-buffer allocation.\n");
            usb_free_stream_buffers(stream);
            return -ENOMEM;
        }
        deb_mem("buffer %d: %p (dma: %Lu)\n",
            stream->buf_num,
stream->buf_list[stream->buf_num], (long long)stream->dma_addr[stream->buf_num]);
        memset(stream->buf_list[stream->buf_num],0,size);
        stream->state |= USB_STATE_URB_BUF;
    }
    deb_mem("allocation successful\n");

    return 0;
}

static int usb_bulk_urb_init(struct usb_data_stream *stream)
{
    int i, j;

    if ((i = usb_allocate_stream_buffers(stream,stream->props.count,
                    stream->props.u.bulk.buffersize)) < 0)
        return i;

    /* allocate the URBs */
    for (i = 0; i < stream->props.count; i++) {
        stream->urb_list[i] = usb_alloc_urb(0, GFP_ATOMIC);
        if (!stream->urb_list[i]) {
            deb_mem("not enough memory for urb_alloc_urb!.\n");
            for (j = 0; j < i; j++)
                usb_free_urb(stream->urb_list[j]);
            return -ENOMEM;
        }
        usb_fill_bulk_urb( stream->urb_list[i], stream->udev,
                usb_rcvbulkpipe(stream->udev,stream->props.endpoint),
                stream->buf_list[i],
                stream->props.u.bulk.buffersize,
                usb_urb_complete, stream);

        stream->urb_list[i]->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
        stream->urb_list[i]->transfer_dma = stream->dma_addr[i];
        stream->urbs_initialized++;
    }
    return 0;
}

static int usb_isoc_urb_init(struct usb_data_stream *stream)
{
    int i,j;

    if ((i = usb_allocate_stream_buffers(stream,stream->props.count,
                    stream->props.u.isoc.framesize*stream->props.u.isoc.framesperurb)) < 0)
        return i;

    /* allocate the URBs */
    for (i = 0; i < stream->props.count; i++) {
        struct urb *urb;
        int frame_offset = 0;

        stream->urb_list[i] = usb_alloc_urb(stream->props.u.isoc.framesperurb, GFP_ATOMIC);
        if (!stream->urb_list[i]) {
            deb_mem("not enough memory for urb_alloc_urb!\n");
            for (j = 0; j < i; j++)
                usb_free_urb(stream->urb_list[j]);
            return -ENOMEM;
        }

        urb = stream->urb_list[i];

        urb->dev = stream->udev;
        urb->context = stream;
        urb->complete = usb_urb_complete;
        urb->pipe = usb_rcvisocpipe(stream->udev,stream->props.endpoint);
        urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
        urb->interval = stream->props.u.isoc.interval;
        urb->number_of_packets = stream->props.u.isoc.framesperurb;
        urb->transfer_buffer_length = stream->buf_size;
        urb->transfer_buffer = stream->buf_list[i];
        urb->transfer_dma = stream->dma_addr[i];

        for (j = 0; j < stream->props.u.isoc.framesperurb; j++) {
            urb->iso_frame_desc[j].offset = frame_offset;
            urb->iso_frame_desc[j].length = stream->props.u.isoc.framesize;
            frame_offset += stream->props.u.isoc.framesize;
        }

        stream->urbs_initialized++;
    }
    return 0;
}

int usb_urb_init(struct usb_data_stream *stream, struct usb_data_stream_properties *props)
{
    if (stream == NULL || props == NULL)
        return -EINVAL;

    memcpy(&stream->props, props, sizeof(*props));

    usb_clear_halt(stream->udev,usb_rcvbulkpipe(stream->udev,stream->props.endpoint));

    if (stream->complete == NULL) {
        err("there is no data callback - this doesn't make sense.");
        return -EINVAL;
    }

    switch (stream->props.type) {
        case USB_BULK:
            return usb_bulk_urb_init(stream);
        case USB_ISOC:
            return usb_isoc_urb_init(stream);
        default:
            err("unknown URB-type for data transfer.");
            return -EINVAL;
    }
}

int usb_urb_exit(struct usb_data_stream *stream)
{
    int i;

    usb_urb_kill(stream);

    for (i = 0; i < stream->urbs_initialized; i++) {
        if (stream->urb_list[i] != NULL) {
            deb_mem("freeing URB no. %d.\n",i);
            /* free the URBs */
            usb_free_urb(stream->urb_list[i]);
        }
    }
    stream->urbs_initialized = 0;

    usb_free_stream_buffers(stream);
    return 0;
}