// 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 */

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 completion 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 completion 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;
}

static 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->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->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];

                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;
}

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--;
                        kfree(stream->buf_list[stream->buf_num]);
                }
        }

        stream->state &= ~USB_STATE_URB_BUF;

        return 0;
}

static 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] = kzalloc(size, GFP_ATOMIC);
                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]);
                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;
}