// SPDX-License-Identifier: GPL-2.0
/* usb-urb.c is part of the DVB USB library.
 *
 * Copyright (C) 2004-6 Patrick Boettcher (patrick.boettcher@posteo.de)
 * 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 completion 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 completion 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_KERNEL,
                                        &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_KERNEL);
                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_KERNEL);
                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;
}