Add missing sys/time.h include
[libftdi] / src / ftdi_stream.c
... / ...
CommitLineData
1/***************************************************************************
2 ftdi_stream.c - description
3 -------------------
4 copyright : (C) 2009 Micah Dowty 2010 Uwe Bonnes
5 email : opensource@intra2net.com
6 ***************************************************************************/
7
8/***************************************************************************
9 * *
10 * This program is free software; you can redistribute it and/or modify *
11 * it under the terms of the GNU Lesser General Public License *
12 * version 2.1 as published by the Free Software Foundation; *
13 * *
14 ***************************************************************************/
15
16/* Adapted from
17 * fastftdi.c - A minimal FTDI FT232H interface for which supports bit-bang
18 * mode, but focuses on very high-performance support for
19 * synchronous FIFO mode. Requires libusb-1.0
20 *
21 * Copyright (C) 2009 Micah Dowty
22 *
23 * Permission is hereby granted, free of charge, to any person obtaining a copy
24 * of this software and associated documentation files (the "Software"), to deal
25 * in the Software without restriction, including without limitation the rights
26 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
27 * copies of the Software, and to permit persons to whom the Software is
28 * furnished to do so, subject to the following conditions:
29 *
30 * The above copyright notice and this permission notice shall be included in
31 * all copies or substantial portions of the Software.
32 *
33 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
34 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
35 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
36 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
37 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
38 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
39 * THE SOFTWARE.
40 */
41
42#include <stdlib.h>
43#include <stdio.h>
44#include <sys/time.h>
45#include <libusb.h>
46
47#include "ftdi.h"
48
49typedef struct
50{
51 FTDIStreamCallback *callback;
52 void *userdata;
53 int packetsize;
54 int activity;
55 int result;
56 FTDIProgressInfo progress;
57} FTDIStreamState;
58
59/* Handle callbacks
60 *
61 * With Exit request, free memory and release the transfer
62 *
63 * state->result is only set when some error happens
64 */
65static void LIBUSB_CALL
66ftdi_readstream_cb(struct libusb_transfer *transfer)
67{
68 FTDIStreamState *state = transfer->user_data;
69 int packet_size = state->packetsize;
70
71 state->activity++;
72 if (transfer->status == LIBUSB_TRANSFER_COMPLETED)
73 {
74 int i;
75 uint8_t *ptr = transfer->buffer;
76 int length = transfer->actual_length;
77 int numPackets = (length + packet_size - 1) / packet_size;
78 int res = 0;
79
80 for (i = 0; i < numPackets; i++)
81 {
82 int payloadLen;
83 int packetLen = length;
84
85 if (packetLen > packet_size)
86 packetLen = packet_size;
87
88 payloadLen = packetLen - 2;
89 state->progress.current.totalBytes += payloadLen;
90
91 res = state->callback(ptr + 2, payloadLen,
92 NULL, state->userdata);
93
94 ptr += packetLen;
95 length -= packetLen;
96 }
97 if (res)
98 {
99 free(transfer->buffer);
100 libusb_free_transfer(transfer);
101 }
102 else
103 {
104 transfer->status = -1;
105 state->result = libusb_submit_transfer(transfer);
106 }
107 }
108 else
109 {
110 fprintf(stderr, "unknown status %d\n",transfer->status);
111 state->result = LIBUSB_ERROR_IO;
112 }
113}
114
115/**
116 Helper function to calculate (unix) time differences
117
118 \param a timeval
119 \param b timeval
120*/
121static double
122TimevalDiff(const struct timeval *a, const struct timeval *b)
123{
124 return (a->tv_sec - b->tv_sec) + 1e-6 * (a->tv_usec - b->tv_usec);
125}
126
127/**
128 Streaming reading of data from the device
129
130 Use asynchronous transfers in libusb-1.0 for high-performance
131 streaming of data from a device interface back to the PC. This
132 function continuously transfers data until either an error occurs
133 or the callback returns a nonzero value. This function returns
134 a libusb error code or the callback's return value.
135
136 For every contiguous block of received data, the callback will
137 be invoked.
138
139 \param ftdi pointer to ftdi_context
140 \param callback to user supplied function for one block of data
141 \param userdata
142 \param packetsPerTransfer number of packets per transfer
143 \param numTransfers Number of transfers per callback
144
145*/
146
147int
148ftdi_readstream(struct ftdi_context *ftdi,
149 FTDIStreamCallback *callback, void *userdata,
150 int packetsPerTransfer, int numTransfers)
151{
152 struct libusb_transfer **transfers;
153 FTDIStreamState state = { callback, userdata, ftdi->max_packet_size, 1 };
154 int bufferSize = packetsPerTransfer * ftdi->max_packet_size;
155 int xferIndex;
156 int err = 0;
157
158 /* Only FT2232H and FT232H know about the synchronous FIFO Mode*/
159 if ((ftdi->type != TYPE_2232H) && (ftdi->type != TYPE_232H))
160 {
161 fprintf(stderr,"Device doesn't support synchronous FIFO mode\n");
162 return 1;
163 }
164
165 /* We don't know in what state we are, switch to reset*/
166 if (ftdi_set_bitmode(ftdi, 0xff, BITMODE_RESET) < 0)
167 {
168 fprintf(stderr,"Can't reset mode\n");
169 return 1;
170 }
171
172 /* Purge anything remaining in the buffers*/
173 if (ftdi_usb_purge_buffers(ftdi) < 0)
174 {
175 fprintf(stderr,"Can't Purge\n");
176 return 1;
177 }
178
179 /*
180 * Set up all transfers
181 */
182
183 transfers = calloc(numTransfers, sizeof *transfers);
184 if (!transfers)
185 {
186 err = LIBUSB_ERROR_NO_MEM;
187 goto cleanup;
188 }
189
190 for (xferIndex = 0; xferIndex < numTransfers; xferIndex++)
191 {
192 struct libusb_transfer *transfer;
193
194 transfer = libusb_alloc_transfer(0);
195 transfers[xferIndex] = transfer;
196 if (!transfer)
197 {
198 err = LIBUSB_ERROR_NO_MEM;
199 goto cleanup;
200 }
201
202 libusb_fill_bulk_transfer(transfer, ftdi->usb_dev, ftdi->out_ep,
203 malloc(bufferSize), bufferSize,
204 ftdi_readstream_cb,
205 &state, 0);
206
207 if (!transfer->buffer)
208 {
209 err = LIBUSB_ERROR_NO_MEM;
210 goto cleanup;
211 }
212
213 transfer->status = -1;
214 err = libusb_submit_transfer(transfer);
215 if (err)
216 goto cleanup;
217 }
218
219 /* Start the transfers only when everything has been set up.
220 * Otherwise the transfers start stuttering and the PC not
221 * fetching data for several to several ten milliseconds
222 * and we skip blocks
223 */
224 if (ftdi_set_bitmode(ftdi, 0xff, BITMODE_SYNCFF) < 0)
225 {
226 fprintf(stderr,"Can't set synchronous fifo mode: %s\n",
227 ftdi_get_error_string(ftdi));
228 goto cleanup;
229 }
230
231 /*
232 * Run the transfers, and periodically assess progress.
233 */
234
235 gettimeofday(&state.progress.first.time, NULL);
236
237 do
238 {
239 FTDIProgressInfo *progress = &state.progress;
240 const double progressInterval = 1.0;
241 struct timeval timeout = { 0, ftdi->usb_read_timeout * 1000};
242 struct timeval now;
243
244 int err = libusb_handle_events_timeout(ftdi->usb_ctx, &timeout);
245 if (err == LIBUSB_ERROR_INTERRUPTED)
246 /* restart interrupted events */
247 err = libusb_handle_events_timeout(ftdi->usb_ctx, &timeout);
248 if (!state.result)
249 {
250 state.result = err;
251 }
252 if (state.activity == 0)
253 state.result = 1;
254 else
255 state.activity = 0;
256
257 // If enough time has elapsed, update the progress
258 gettimeofday(&now, NULL);
259 if (TimevalDiff(&now, &progress->current.time) >= progressInterval)
260 {
261 progress->current.time = now;
262 progress->totalTime = TimevalDiff(&progress->current.time,
263 &progress->first.time);
264
265 if (progress->prev.totalBytes)
266 {
267 // We have enough information to calculate rates
268
269 double currentTime;
270
271 currentTime = TimevalDiff(&progress->current.time,
272 &progress->prev.time);
273
274 progress->totalRate =
275 progress->current.totalBytes /progress->totalTime;
276 progress->currentRate =
277 (progress->current.totalBytes -
278 progress->prev.totalBytes) / currentTime;
279 }
280
281 state.callback(NULL, 0, progress, state.userdata);
282 progress->prev = progress->current;
283
284 }
285 } while (!state.result);
286
287 /*
288 * Cancel any outstanding transfers, and free memory.
289 */
290
291cleanup:
292 fprintf(stderr, "cleanup\n");
293 if (transfers)
294 free(transfers);
295 if (err)
296 return err;
297 else
298 return state.result;
299}
300