usb-urb.c

  1// SPDX-License-Identifier: GPL-2.0
  2/* usb-urb.c is part of the DVB USB library.
  3 *
  4 * Copyright (C) 2004-6 Patrick Boettcher (patrick.boettcher@posteo.de)
  5 * see dvb-usb-init.c for copyright information.
  6 *
  7 * This file keeps functions for initializing and handling the
  8 * BULK and ISOC USB data transfers in a generic way.
  9 * Can be used for DVB-only and also, that's the plan, for
 10 * Hybrid USB devices (analog and DVB).
 11 */
 12#include "dvb-usb-common.h"
 13
 14/* URB stuff for streaming */
 15static void usb_urb_complete(struct urb *urb)
 16{
 17	struct usb_data_stream *stream = urb->context;
 18	int ptype = usb_pipetype(urb->pipe);
 19	int i;
 20	u8 *b;
 21
 22	deb_uxfer("'%s' urb completed. status: %d, length: %d/%d, pack_num: %d, errors: %d\n",
 23		ptype == PIPE_ISOCHRONOUS ? "isoc" : "bulk",
 24		urb->status,urb->actual_length,urb->transfer_buffer_length,
 25		urb->number_of_packets,urb->error_count);
 26
 27	switch (urb->status) {
 28		case 0:         /* success */
 29		case -ETIMEDOUT:    /* NAK */
 30			break;
 31		case -ECONNRESET:   /* kill */
 32		case -ENOENT:
 33		case -ESHUTDOWN:
 34			return;
 35		default:        /* error */
 36			deb_ts("urb completion error %d.\n", urb->status);
 37			break;
 38	}
 39
 40	b = (u8 *) urb->transfer_buffer;
 41	switch (ptype) {
 42		case PIPE_ISOCHRONOUS:
 43			for (i = 0; i < urb->number_of_packets; i++) {
 44
 45				if (urb->iso_frame_desc[i].status != 0)
 46					deb_ts("iso frame descriptor has an error: %d\n",urb->iso_frame_desc[i].status);
 47				else if (urb->iso_frame_desc[i].actual_length > 0)
 48					stream->complete(stream, b + urb->iso_frame_desc[i].offset, urb->iso_frame_desc[i].actual_length);
 49
 50				urb->iso_frame_desc[i].status = 0;
 51				urb->iso_frame_desc[i].actual_length = 0;
 52			}
 53			debug_dump(b,20,deb_uxfer);
 54			break;
 55		case PIPE_BULK:
 56			if (urb->actual_length > 0)
 57				stream->complete(stream, b, urb->actual_length);
 58			break;
 59		default:
 60			err("unknown endpoint type in completion handler.");
 61			return;
 62	}
 63	usb_submit_urb(urb,GFP_ATOMIC);
 64}
 65
 66int usb_urb_kill(struct usb_data_stream *stream)
 67{
 68	int i;
 69	for (i = 0; i < stream->urbs_submitted; i++) {
 70		deb_ts("killing URB no. %d.\n",i);
 71
 72		/* stop the URB */
 73		usb_kill_urb(stream->urb_list[i]);
 74	}
 75	stream->urbs_submitted = 0;
 76	return 0;
 77}
 78
 79int usb_urb_submit(struct usb_data_stream *stream)
 80{
 81	int i,ret;
 82	for (i = 0; i < stream->urbs_initialized; i++) {
 83		deb_ts("submitting URB no. %d\n",i);
 84		if ((ret = usb_submit_urb(stream->urb_list[i],GFP_ATOMIC))) {
 85			err("could not submit URB no. %d - get them all back",i);
 86			usb_urb_kill(stream);
 87			return ret;
 88		}
 89		stream->urbs_submitted++;
 90	}
 91	return 0;
 92}
 93
 94static int usb_free_stream_buffers(struct usb_data_stream *stream)
 95{
 96	if (stream->state & USB_STATE_URB_BUF) {
 97		while (stream->buf_num) {
 98			stream->buf_num--;
 99			deb_mem("freeing buffer %d\n",stream->buf_num);
100			usb_free_coherent(stream->udev, stream->buf_size,
101					  stream->buf_list[stream->buf_num],
102					  stream->dma_addr[stream->buf_num]);
103		}
104	}
105
106	stream->state &= ~USB_STATE_URB_BUF;
107
108	return 0;
109}
110
111static int usb_allocate_stream_buffers(struct usb_data_stream *stream, int num, unsigned long size)
112{
113	stream->buf_num = 0;
114	stream->buf_size = size;
115
116	deb_mem("all in all I will use %lu bytes for streaming\n",num*size);
117
118	for (stream->buf_num = 0; stream->buf_num < num; stream->buf_num++) {
119		deb_mem("allocating buffer %d\n",stream->buf_num);
120		if (( stream->buf_list[stream->buf_num] =
121					usb_alloc_coherent(stream->udev, size, GFP_KERNEL,
122					&stream->dma_addr[stream->buf_num]) ) == NULL) {
123			deb_mem("not enough memory for urb-buffer allocation.\n");
124			usb_free_stream_buffers(stream);
125			return -ENOMEM;
126		}
127		deb_mem("buffer %d: %p (dma: %Lu)\n",
128			stream->buf_num,
129stream->buf_list[stream->buf_num], (long long)stream->dma_addr[stream->buf_num]);
130		memset(stream->buf_list[stream->buf_num],0,size);
131		stream->state |= USB_STATE_URB_BUF;
132	}
133	deb_mem("allocation successful\n");
134
135	return 0;
136}
137
138static int usb_bulk_urb_init(struct usb_data_stream *stream)
139{
140	int i, j;
141
142	if ((i = usb_allocate_stream_buffers(stream,stream->props.count,
143					stream->props.u.bulk.buffersize)) < 0)
144		return i;
145
146	/* allocate the URBs */
147	for (i = 0; i < stream->props.count; i++) {
148		stream->urb_list[i] = usb_alloc_urb(0, GFP_KERNEL);
149		if (!stream->urb_list[i]) {
150			deb_mem("not enough memory for urb_alloc_urb!.\n");
151			for (j = 0; j < i; j++)
152				usb_free_urb(stream->urb_list[j]);
153			return -ENOMEM;
154		}
155		usb_fill_bulk_urb( stream->urb_list[i], stream->udev,
156				usb_rcvbulkpipe(stream->udev,stream->props.endpoint),
157				stream->buf_list[i],
158				stream->props.u.bulk.buffersize,
159				usb_urb_complete, stream);
160
161		stream->urb_list[i]->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
162		stream->urb_list[i]->transfer_dma = stream->dma_addr[i];
163		stream->urbs_initialized++;
164	}
165	return 0;
166}
167
168static int usb_isoc_urb_init(struct usb_data_stream *stream)
169{
170	int i,j;
171
172	if ((i = usb_allocate_stream_buffers(stream,stream->props.count,
173					stream->props.u.isoc.framesize*stream->props.u.isoc.framesperurb)) < 0)
174		return i;
175
176	/* allocate the URBs */
177	for (i = 0; i < stream->props.count; i++) {
178		struct urb *urb;
179		int frame_offset = 0;
180
181		stream->urb_list[i] = usb_alloc_urb(stream->props.u.isoc.framesperurb, GFP_KERNEL);
182		if (!stream->urb_list[i]) {
183			deb_mem("not enough memory for urb_alloc_urb!\n");
184			for (j = 0; j < i; j++)
185				usb_free_urb(stream->urb_list[j]);
186			return -ENOMEM;
187		}
188
189		urb = stream->urb_list[i];
190
191		urb->dev = stream->udev;
192		urb->context = stream;
193		urb->complete = usb_urb_complete;
194		urb->pipe = usb_rcvisocpipe(stream->udev,stream->props.endpoint);
195		urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
196		urb->interval = stream->props.u.isoc.interval;
197		urb->number_of_packets = stream->props.u.isoc.framesperurb;
198		urb->transfer_buffer_length = stream->buf_size;
199		urb->transfer_buffer = stream->buf_list[i];
200		urb->transfer_dma = stream->dma_addr[i];
201
202		for (j = 0; j < stream->props.u.isoc.framesperurb; j++) {
203			urb->iso_frame_desc[j].offset = frame_offset;
204			urb->iso_frame_desc[j].length = stream->props.u.isoc.framesize;
205			frame_offset += stream->props.u.isoc.framesize;
206		}
207
208		stream->urbs_initialized++;
209	}
210	return 0;
211}
212
213int usb_urb_init(struct usb_data_stream *stream, struct usb_data_stream_properties *props)
214{
215	if (stream == NULL || props == NULL)
216		return -EINVAL;
217
218	memcpy(&stream->props, props, sizeof(*props));
219
220	usb_clear_halt(stream->udev,usb_rcvbulkpipe(stream->udev,stream->props.endpoint));
221
222	if (stream->complete == NULL) {
223		err("there is no data callback - this doesn't make sense.");
224		return -EINVAL;
225	}
226
227	switch (stream->props.type) {
228		case USB_BULK:
229			return usb_bulk_urb_init(stream);
230		case USB_ISOC:
231			return usb_isoc_urb_init(stream);
232		default:
233			err("unknown URB-type for data transfer.");
234			return -EINVAL;
235	}
236}
237
238int usb_urb_exit(struct usb_data_stream *stream)
239{
240	int i;
241
242	usb_urb_kill(stream);
243
244	for (i = 0; i < stream->urbs_initialized; i++) {
245		if (stream->urb_list[i] != NULL) {
246			deb_mem("freeing URB no. %d.\n",i);
247			/* free the URBs */
248			usb_free_urb(stream->urb_list[i]);
249		}
250	}
251	stream->urbs_initialized = 0;
252
253	usb_free_stream_buffers(stream);
254	return 0;
255}