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 */

int usb_urb_reconfig(struct usb_data_stream *stream,
        struct usb_data_stream_properties *props);

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;

    dev_dbg_ratelimited(&stream->udev->dev, "%s: %s urb completed " \
            "status=%d length=%d/%d pack_num=%d errors=%d\n",
            __func__, 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 */
        dev_dbg_ratelimited(&stream->udev->dev,
                "%s: urb completition failed=%d\n",
                __func__, 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)
                dev_dbg(&stream->udev->dev, "%s: iso frame " \
                        "descriptor has an error=%d\n",
                        __func__,
                        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;
        }
        break;
    case PIPE_BULK:
        if (urb->actual_length > 0)
            stream->complete(stream, b, urb->actual_length);
        break;
    default:
        dev_err(&stream->udev->dev, "%s: unknown endpoint type in " \
                "completition handler\n", KBUILD_MODNAME);
        return;
    }
    usb_submit_urb(urb, GFP_ATOMIC);
}

int usb_urb_killv2(struct usb_data_stream *stream)
{
    int i;
    for (i = 0; i < stream->urbs_submitted; i++) {
        dev_dbg(&stream->udev->dev, "%s: kill urb=%d\n", __func__, i);
        /* stop the URB */
        usb_kill_urb(stream->urb_list[i]);
    }
    stream->urbs_submitted = 0;
    return 0;
}

int usb_urb_submitv2(struct usb_data_stream *stream,
        struct usb_data_stream_properties *props)
{
    int i, ret;

    if (props) {
        ret = usb_urb_reconfig(stream, props);
        if (ret < 0)
            return ret;
    }

    for (i = 0; i < stream->urbs_initialized; i++) {
        dev_dbg(&stream->udev->dev, "%s: submit urb=%d\n", __func__, i);
        ret = usb_submit_urb(stream->urb_list[i], GFP_ATOMIC);
        if (ret) {
            dev_err(&stream->udev->dev, "%s: could not submit " \
                    "urb no. %d - get them all back\n",
                    KBUILD_MODNAME, i);
            usb_urb_killv2(stream);
            return ret;
        }
        stream->urbs_submitted++;
    }
    return 0;
}

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

    usb_urb_killv2(stream);

    for (i = stream->urbs_initialized - 1; i >= 0; i--) {
        if (stream->urb_list[i]) {
            dev_dbg(&stream->udev->dev, "%s: free urb=%d\n",
                    __func__, i);
            /* free the URBs */
            usb_free_urb(stream->urb_list[i]);
        }
    }
    stream->urbs_initialized = 0;

    return 0;
}

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

    /* allocate the URBs */
    for (i = 0; i < stream->props.count; i++) {
        dev_dbg(&stream->udev->dev, "%s: alloc urb=%d\n", __func__, i);
        stream->urb_list[i] = usb_alloc_urb(0, GFP_ATOMIC);
        if (!stream->urb_list[i]) {
            dev_dbg(&stream->udev->dev, "%s: failed\n", __func__);
            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_urb_alloc_isoc_urbs(struct usb_data_stream *stream)
{
    int i, j;

    /* allocate the URBs */
    for (i = 0; i < stream->props.count; i++) {
        struct urb *urb;
        int frame_offset = 0;
        dev_dbg(&stream->udev->dev, "%s: alloc urb=%d\n", __func__, i);
        stream->urb_list[i] = usb_alloc_urb(
                stream->props.u.isoc.framesperurb, GFP_ATOMIC);
        if (!stream->urb_list[i]) {
            dev_dbg(&stream->udev->dev, "%s: failed\n", __func__);
            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->props.u.isoc.framesize *
                stream->props.u.isoc.framesperurb;
        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_free_stream_buffers(struct usb_data_stream *stream)
{
    if (stream->state & USB_STATE_URB_BUF) {
        while (stream->buf_num) {
            stream->buf_num--;
            dev_dbg(&stream->udev->dev, "%s: free buf=%d\n",
                __func__, 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;
}

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

    dev_dbg(&stream->udev->dev, "%s: all in all I will use %lu bytes for " \
            "streaming\n", __func__,  num * size);

    for (stream->buf_num = 0; stream->buf_num < num; stream->buf_num++) {
        stream->buf_list[stream->buf_num] = usb_alloc_coherent(
                stream->udev, size, GFP_ATOMIC,
                &stream->dma_addr[stream->buf_num]);
        if (!stream->buf_list[stream->buf_num]) {
            dev_dbg(&stream->udev->dev, "%s: alloc buf=%d failed\n",
                    __func__, stream->buf_num);
            usb_free_stream_buffers(stream);
            return -ENOMEM;
        }

        dev_dbg(&stream->udev->dev, "%s: alloc buf=%d %p (dma %llu)\n",
                __func__, 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;
    }

    return 0;
}

int usb_urb_reconfig(struct usb_data_stream *stream,
        struct usb_data_stream_properties *props)
{
    int buf_size;

    if (!props)
        return 0;

    /* check allocated buffers are large enough for the request */
    if (props->type == USB_BULK) {
        buf_size = stream->props.u.bulk.buffersize;
    } else if (props->type == USB_ISOC) {
        buf_size = props->u.isoc.framesize * props->u.isoc.framesperurb;
    } else {
        dev_err(&stream->udev->dev, "%s: invalid endpoint type=%d\n",
                KBUILD_MODNAME, props->type);
        return -EINVAL;
    }

    if (stream->buf_num < props->count || stream->buf_size < buf_size) {
        dev_err(&stream->udev->dev, "%s: cannot reconfigure as " \
                "allocated buffers are too small\n",
                KBUILD_MODNAME);
        return -EINVAL;
    }

    /* check if all fields are same */
    if (stream->props.type == props->type &&
            stream->props.count == props->count &&
            stream->props.endpoint == props->endpoint) {
        if (props->type == USB_BULK &&
                props->u.bulk.buffersize ==
                stream->props.u.bulk.buffersize)
            return 0;
        else if (props->type == USB_ISOC &&
                props->u.isoc.framesperurb ==
                stream->props.u.isoc.framesperurb &&
                props->u.isoc.framesize ==
                stream->props.u.isoc.framesize &&
                props->u.isoc.interval ==
                stream->props.u.isoc.interval)
            return 0;
    }

    dev_dbg(&stream->udev->dev, "%s: re-alloc urbs\n", __func__);

    usb_urb_free_urbs(stream);
    memcpy(&stream->props, props, sizeof(*props));
    if (props->type == USB_BULK)
        return usb_urb_alloc_bulk_urbs(stream);
    else if (props->type == USB_ISOC)
        return usb_urb_alloc_isoc_urbs(stream);

    return 0;
}

int usb_urb_initv2(struct usb_data_stream *stream,
        const struct usb_data_stream_properties *props)
{
    int ret;

    if (!stream || !props)
        return -EINVAL;

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

    if (!stream->complete) {
        dev_err(&stream->udev->dev, "%s: there is no data callback - " \
                "this doesn't make sense\n", KBUILD_MODNAME);
        return -EINVAL;
    }

    switch (stream->props.type) {
    case USB_BULK:
        ret = usb_alloc_stream_buffers(stream, stream->props.count,
                stream->props.u.bulk.buffersize);
        if (ret < 0)
            return ret;

        return usb_urb_alloc_bulk_urbs(stream);
    case USB_ISOC:
        ret = usb_alloc_stream_buffers(stream, stream->props.count,
                stream->props.u.isoc.framesize *
                stream->props.u.isoc.framesperurb);
        if (ret < 0)
            return ret;

        return usb_urb_alloc_isoc_urbs(stream);
    default:
        dev_err(&stream->udev->dev, "%s: unknown urb-type for data " \
                "transfer\n", KBUILD_MODNAME);
        return -EINVAL;
    }
}

int usb_urb_exitv2(struct usb_data_stream *stream)
{
    usb_urb_free_urbs(stream);
    usb_free_stream_buffers(stream);

    return 0;
}