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scanalogic2: Shorten a few function name prefixes.
[libsigrok.git] / hardware / ikalogic-scanalogic2 / protocol.c
1 /*
2  * This file is part of the libsigrok project.
3  *
4  * Copyright (C) 2013 Marc Schink <sigrok-dev@marcschink.de>
5  *
6  * This program is free software: you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation, either version 3 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19
20 #include "protocol.h"
21
22 extern struct sr_dev_driver ikalogic_scanalogic2_driver_info;
23 static struct sr_dev_driver *di = &ikalogic_scanalogic2_driver_info;
24
25 extern uint64_t sl2_samplerates[NUM_SAMPLERATES];
26
27 static void stop_acquisition(struct sr_dev_inst *sdi)
28 {
29         struct dev_context *devc;
30         struct sr_datafeed_packet packet;
31         unsigned int i;
32
33         devc = sdi->priv;
34
35         /* Remove USB file descriptors from polling. */
36         for (i = 0; i < devc->num_usbfd; i++)
37                 sr_source_remove(devc->usbfd[i]);
38
39         g_free(devc->usbfd);
40
41         packet.type = SR_DF_END;
42         sr_session_send(devc->cb_data, &packet);
43
44         sdi->status = SR_ST_ACTIVE;
45 }
46
47 static void abort_acquisition(struct sr_dev_inst *sdi)
48 {
49         struct dev_context *devc;
50         struct sr_datafeed_packet packet;
51         unsigned int i;
52
53         devc = sdi->priv;
54
55         /* Remove USB file descriptors from polling. */
56         for (i = 0; i < devc->num_usbfd; i++)
57                 sr_source_remove(devc->usbfd[i]);
58
59         g_free(devc->usbfd);
60
61         packet.type = SR_DF_END;
62         sr_session_send(devc->cb_data, &packet);
63
64         sdi->driver->dev_close(sdi);
65 }
66
67 static void buffer_sample_data(const struct sr_dev_inst *sdi)
68 {
69         struct dev_context *devc;
70         unsigned int offset, packet_length;
71
72         devc = sdi->priv;
73
74         if (devc->probes[devc->channel]->enabled) {
75                 offset = devc->sample_packet * PACKET_NUM_SAMPLE_BYTES;
76
77                 /*
78                  * Determine the packet length to ensure that the last packet
79                  * will not exceed the buffer size.
80                  */
81                 packet_length = MIN(PACKET_NUM_SAMPLE_BYTES,
82                         MAX_DEV_SAMPLE_BYTES - offset);
83
84                 /*
85                  * Skip the first 4 bytes of the source buffer because they
86                  * contain channel and packet information only.
87                  */
88                 memcpy(devc->sample_buffer[devc->channel] + offset,
89                         devc->xfer_data_in + 4, packet_length);
90         }
91 }
92
93 static void process_sample_data(const struct sr_dev_inst *sdi)
94 {
95         struct dev_context *devc;
96         struct sr_datafeed_packet packet;
97         struct sr_datafeed_logic logic;
98         uint8_t i, j, tmp, buffer[PACKET_NUM_SAMPLES], *ptr[NUM_PROBES];
99         uint16_t offset, n = 0;
100         int8_t k;
101
102         devc = sdi->priv;
103         offset = devc->sample_packet * PACKET_NUM_SAMPLE_BYTES;
104
105         /*
106          * Array of pointers to the sample data of all channels up to the last
107          * enabled one for an uniform access to them. Note that the currently
108          * received samples always belong to the last enabled channel.
109          */
110         for (i = 0; i < devc->num_enabled_probes - 1; i++)
111                 ptr[i] = devc->sample_buffer[devc->probe_map[i]] + offset;
112
113         /*
114          * Skip the first 4 bytes of the buffer because they contain channel
115          * and packet information only.
116          */
117         ptr[i] = devc->xfer_data_in + 4;
118
119         for (i = 0; i < PACKET_NUM_SAMPLE_BYTES; i++) {
120                 /* Stop processing if all requested samples are processed. */
121                 if (devc->samples_processed == devc->limit_samples)
122                         break;
123
124                 k = 7;
125
126                 if (devc->samples_processed == 0) {
127                         /*
128                          * Adjust the position of the first sample to be
129                          * processed because possibly more samples than
130                          * necessary might have been aquired. This is because
131                          * the number of aquired samples is always rounded up
132                          * to a multiple of 8.
133                          */
134                         k = k - (devc->pre_trigger_bytes * 8) +
135                                 devc->pre_trigger_samples;
136
137                         sr_dbg("Start processing at sample: %d.", 7 - k);
138
139                         /*
140                          * Send the trigger before the first sample is
141                          * processed if no pre trigger samples were calculated
142                          * through the capture ratio.
143                          */
144                         if (devc->trigger_type != TRIGGER_TYPE_NONE &&
145                                         devc->pre_trigger_samples == 0) {
146                                 packet.type = SR_DF_TRIGGER;
147                                 sr_session_send(devc->cb_data, &packet);
148                         }
149                 }
150
151                 for (; k >= 0; k--) {
152                         /*
153                          * Stop processing if all requested samples are
154                          * processed.
155                          */
156                         if (devc->samples_processed == devc->limit_samples)
157                                 break;
158
159                         buffer[n] = 0;
160
161                         /*
162                          * Extract the current sample for each enabled channel
163                          * and store them in the buffer.
164                          */
165                         for (j = 0; j < devc->num_enabled_probes; j++) {
166                                 tmp = (ptr[j][i] & (1 << k)) >> k;
167                                 buffer[n] |= tmp << devc->probe_map[j];
168                         }
169
170                         n++;
171                         devc->samples_processed++;
172
173                         /*
174                          * Send all processed samples and the trigger if the
175                          * number of processed samples reaches the calculated
176                          * number of pre trigger samples.
177                          */
178                         if (devc->samples_processed == devc->pre_trigger_samples &&
179                                         devc->trigger_type != TRIGGER_TYPE_NONE) {
180                                 packet.type = SR_DF_LOGIC;
181                                 packet.payload = &logic;
182                                 logic.length = n;
183                                 logic.unitsize = 1;
184                                 logic.data = buffer;
185                                 sr_session_send(devc->cb_data, &packet);
186
187                                 packet.type = SR_DF_TRIGGER;
188                                 sr_session_send(devc->cb_data, &packet);
189
190                                 n = 0;
191                         }
192                 }
193         }
194
195         if (n > 0) {
196                 packet.type = SR_DF_LOGIC;
197                 packet.payload = &logic;
198                 logic.length = n;
199                 logic.unitsize = 1;
200                 logic.data = buffer;
201                 sr_session_send(devc->cb_data, &packet);
202         }
203 }
204
205 SR_PRIV int ikalogic_scanalogic2_receive_data(int fd, int revents, void *cb_data)
206 {
207         struct sr_dev_inst *sdi;
208         struct dev_context *devc;
209         struct drv_context *drvc;
210         struct timeval tv;
211         int64_t current_time, time_elapsed;
212         int ret = 0;
213
214         (void)fd;
215         (void)revents;
216
217         if (!(sdi = cb_data))
218                 return TRUE;
219
220         if (!(devc = sdi->priv))
221                 return TRUE;
222
223         drvc = di->priv;
224         current_time = g_get_monotonic_time();
225
226         if (devc->state == STATE_WAIT_DATA_READY &&
227                         !devc->wait_data_ready_locked) {
228                 time_elapsed = current_time - devc->wait_data_ready_time;
229
230                 /*
231                  * Check here for stopping in addition to the transfer
232                  * callback functions to avoid waiting until the
233                  * WAIT_DATA_READY_INTERVAL has expired.
234                  */
235                 if (sdi->status == SR_ST_STOPPING) {
236                         if (!devc->stopping_in_progress) {
237                                 devc->next_state = STATE_RESET_AND_IDLE;
238                                 devc->stopping_in_progress = TRUE;
239                                 ret = libusb_submit_transfer(devc->xfer_in);
240                         }
241                 } else if (time_elapsed >= WAIT_DATA_READY_INTERVAL) {
242                         devc->wait_data_ready_locked = TRUE;
243                         ret = libusb_submit_transfer(devc->xfer_in);
244                 }
245         }
246
247         if (ret != 0) {
248                 sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
249                 abort_acquisition(sdi);
250                 return TRUE;
251         }
252
253         tv.tv_sec = 0;
254         tv.tv_usec = 0;
255
256         libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx, &tv,
257                 NULL);
258
259         /* Check if an error occurred on a transfer. */
260         if (devc->transfer_error)
261                 abort_acquisition(sdi);
262
263         return TRUE;
264 }
265
266 SR_PRIV void sl2_receive_transfer_in( struct libusb_transfer *transfer)
267 {
268         struct sr_dev_inst *sdi;
269         struct dev_context *devc;
270         uint8_t last_channel;
271         int ret = 0;
272
273         sdi = transfer->user_data;
274         devc = sdi->priv;
275
276         if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
277                 sr_err("Transfer to device failed: %i.", transfer->status);
278                 devc->transfer_error = TRUE;
279                 return;
280         }
281
282         if (sdi->status == SR_ST_STOPPING && !devc->stopping_in_progress) {
283                 devc->next_state = STATE_RESET_AND_IDLE;
284                 devc->stopping_in_progress = TRUE;
285
286                 if (libusb_submit_transfer(devc->xfer_in) != 0) {
287                         sr_err("Submit transfer failed: %s.",
288                                 libusb_error_name(ret));
289                         devc->transfer_error = TRUE;
290                 }
291
292                 return;
293         }
294
295         sr_spew("State changed from %i to %i.", devc->state, devc->next_state);
296         devc->state = devc->next_state;
297
298         if (devc->state == STATE_WAIT_DATA_READY) {
299                 /* Check if the received data are a valid device status. */
300                 if (devc->xfer_data_in[0] == 0x05) {
301                         if (devc->xfer_data_in[1] == STATUS_WAITING_FOR_TRIGGER)
302                                 sr_dbg("Waiting for trigger.");
303                         else if (devc->xfer_data_in[1] == STATUS_SAMPLING)
304                                 sr_dbg("Sampling in progress.");
305                 }
306
307                 /*
308                  * Check if the received data are a valid device status and the
309                  * sample data are ready.
310                  */
311                 if (devc->xfer_data_in[0] == 0x05 &&
312                                 devc->xfer_data_in[1] == STATUS_DATA_READY) {
313                         devc->next_state = STATE_RECEIVE_DATA;
314                         ret = libusb_submit_transfer(transfer);
315                 } else {
316                         devc->wait_data_ready_locked = FALSE;
317                         devc->wait_data_ready_time = g_get_monotonic_time();
318                 }
319         } else if (devc->state == STATE_RECEIVE_DATA) {
320                 last_channel = devc->probe_map[devc->num_enabled_probes - 1];
321
322                 if (devc->channel < last_channel) {
323                         buffer_sample_data(sdi);
324                 } else if (devc->channel == last_channel) {
325                         process_sample_data(sdi);
326                 } else {
327                         /*
328                          * Stop acquisition because all samples of enabled
329                          * probes are processed.
330                          */
331                         devc->next_state = STATE_RESET_AND_IDLE;
332                 }
333
334                 devc->sample_packet++;
335                 devc->sample_packet %= devc->num_sample_packets;
336
337                 if (devc->sample_packet == 0)
338                         devc->channel++;
339
340                 ret = libusb_submit_transfer(transfer);
341         } else if (devc->state == STATE_RESET_AND_IDLE) {
342                 /* Check if the received data are a valid device status. */
343                 if (devc->xfer_data_in[0] == 0x05) {
344                         if (devc->xfer_data_in[1] == STATUS_DEVICE_READY) {
345                                 devc->next_state = STATE_IDLE;
346                                 devc->xfer_data_out[0] = CMD_IDLE;
347                         } else {
348                                 devc->next_state = STATE_WAIT_DEVICE_READY;
349                                 devc->xfer_data_out[0] = CMD_RESET;
350                         }
351
352                         ret = libusb_submit_transfer(devc->xfer_out);
353                 } else {
354                         /*
355                          * The received device status is invalid which
356                          * indicates that the device is not ready to accept
357                          * commands. Request a new device status until a valid
358                          * device status is received.
359                          */
360                         ret = libusb_submit_transfer(transfer);
361                 }
362         } else if (devc->state == STATE_WAIT_DEVICE_READY) {
363                 /* Check if the received data are a valid device status. */
364                 if (devc->xfer_data_in[0] == 0x05) {
365                         if (devc->xfer_data_in[1] == STATUS_DEVICE_READY) {
366                                 devc->next_state = STATE_IDLE;
367                                 devc->xfer_data_out[0] = CMD_IDLE;
368                         } else {
369                                 /*
370                                  * The received device status is valid but the
371                                  * device is not ready. Probably the device did
372                                  * not recognize the last reset. Reset the
373                                  * device again.
374                                  */
375                                 devc->xfer_data_out[0] = CMD_RESET;
376                         }
377
378                         ret = libusb_submit_transfer(devc->xfer_out);
379                 } else {
380                         /*
381                          * The device is not ready and therefore not able to
382                          * change to the idle state. Request a new device
383                          * status until the device is ready.
384                          */
385                         ret = libusb_submit_transfer(transfer);
386                 }
387         }
388
389         if (ret != 0) {
390                 sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
391                 devc->transfer_error = TRUE;
392         }
393 }
394
395 SR_PRIV void sl2_receive_transfer_out( struct libusb_transfer *transfer)
396 {
397         struct sr_dev_inst *sdi;
398         struct dev_context *devc;
399         int ret = 0;
400
401         sdi = transfer->user_data;
402         devc = sdi->priv;
403
404         if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
405                 sr_err("Transfer to device failed: %i.", transfer->status);
406                 devc->transfer_error = TRUE;
407                 return;
408         }
409
410         if (sdi->status == SR_ST_STOPPING && !devc->stopping_in_progress) {
411                 devc->next_state = STATE_RESET_AND_IDLE;
412                 devc->stopping_in_progress = TRUE;
413
414                 if (libusb_submit_transfer(devc->xfer_in) != 0) {
415                         sr_err("Submit transfer failed: %s.",
416                                 libusb_error_name(ret));
417
418                         devc->transfer_error = TRUE;
419                 }
420
421                 return;
422         }
423
424         sr_spew("State changed from %i to %i.", devc->state, devc->next_state);
425         devc->state = devc->next_state;
426
427         if (devc->state == STATE_IDLE) {
428                 stop_acquisition(sdi);
429         } else if (devc->state == STATE_SAMPLE) {
430                 devc->next_state = STATE_WAIT_DATA_READY;
431                 ret = libusb_submit_transfer(devc->xfer_in);
432         } else if (devc->state == STATE_WAIT_DEVICE_READY) {
433                 ret = libusb_submit_transfer(devc->xfer_in);
434         }
435
436         if (ret != 0) {
437                 sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
438                 devc->transfer_error = TRUE;
439         }
440 }
441
442 SR_PRIV int sl2_set_samplerate(const struct sr_dev_inst *sdi,
443                 uint64_t samplerate)
444 {
445         struct dev_context *devc;
446         unsigned int i;
447
448         devc = sdi->priv;
449
450         for (i = 0; i < NUM_SAMPLERATES; i++) {
451                 if (sl2_samplerates[i] == samplerate) {
452                         devc->samplerate = samplerate;
453                         devc->samplerate_id = NUM_SAMPLERATES - i - 1;
454                         return SR_OK;
455                 }
456         }
457
458         return SR_ERR_ARG;
459 }
460
461 SR_PRIV int sl2_set_limit_samples(const struct sr_dev_inst *sdi,
462                                   uint64_t limit_samples)
463 {
464         struct dev_context *devc;
465
466         devc = sdi->priv;
467
468         if (limit_samples == 0) {
469                 sr_err("Invalid number of limit samples: %" PRIu64 ".",
470                         limit_samples);
471                 return SR_ERR_ARG;
472         }
473
474         if (limit_samples > MAX_SAMPLES)
475                 limit_samples = MAX_SAMPLES;
476
477         sr_dbg("Limit samples set to %" PRIu64 ".", limit_samples);
478
479         devc->limit_samples = limit_samples;
480
481         return SR_OK;
482 }
483
484 SR_PRIV void sl2_configure_trigger(const struct sr_dev_inst *sdi)
485 {
486         struct dev_context *devc;
487         struct sr_probe *probe;
488         uint8_t trigger_type;
489         int probe_index, num_triggers_anyedge;
490         char *trigger;
491         GSList *l;
492
493         devc = sdi->priv;
494
495         /* Disable the trigger by default. */
496         devc->trigger_channel = TRIGGER_CHANNEL_0;
497         devc->trigger_type = TRIGGER_TYPE_NONE;
498
499         num_triggers_anyedge = 0;
500
501         for (l = sdi->probes, probe_index = 0; l; l = l->next, probe_index++) {
502                 probe = l->data;
503                 trigger = probe->trigger;
504
505                 if (!trigger || !probe->enabled)
506                         continue;
507
508                 switch (*trigger) {
509                 case 'r':
510                         trigger_type = TRIGGER_TYPE_POSEDGE;
511                         break;
512                 case 'f':
513                         trigger_type = TRIGGER_TYPE_NEGEDGE;
514                         break;
515                 case 'c':
516                         trigger_type = TRIGGER_TYPE_ANYEDGE;
517                         num_triggers_anyedge++;
518                         break;
519                 default:
520                         continue;
521                 }
522
523                 devc->trigger_channel = probe_index + 1;
524                 devc->trigger_type = trigger_type;
525         }
526
527         /*
528          * Set trigger to any edge on all channels if the trigger for each
529          * channel is set to any edge.
530          */
531         if (num_triggers_anyedge == NUM_PROBES) {
532                 devc->trigger_channel = TRIGGER_CHANNEL_ALL;
533                 devc->trigger_type = TRIGGER_TYPE_ANYEDGE;
534         }
535
536         sr_dbg("Trigger set to channel 0x%02x and type 0x%02x.",
537                 devc->trigger_channel, devc->trigger_type);
538 }
539
540 SR_PRIV int sl2_set_capture_ratio(const struct sr_dev_inst *sdi,
541                                   uint64_t capture_ratio)
542 {
543         struct dev_context *devc;
544
545         devc = sdi->priv;
546
547         if (capture_ratio > 100) {
548                 sr_err("Invalid capture ratio: %" PRIu64 " %%.", capture_ratio);
549                 return SR_ERR_ARG;
550         }
551
552         sr_info("Capture ratio set to %" PRIu64 " %%.", capture_ratio);
553
554         devc->capture_ratio = capture_ratio;
555
556         return SR_OK;
557 }
558
559 SR_PRIV int sl2_set_after_trigger_delay(const struct sr_dev_inst *sdi,
560                                         uint64_t after_trigger_delay)
561 {
562         struct dev_context *devc;
563
564         devc = sdi->priv;
565
566         if (after_trigger_delay > MAX_AFTER_TRIGGER_DELAY) {
567                 sr_err("Invalid after trigger delay: %" PRIu64 " ms.",
568                         after_trigger_delay);
569                 return SR_ERR_ARG;
570         }
571
572         sr_info("After trigger delay set to %" PRIu64 " ms.",
573                 after_trigger_delay);
574
575         devc->after_trigger_delay = after_trigger_delay;
576
577         return SR_OK;
578 }
579
580 SR_PRIV void sl2_calculate_trigger_samples(const struct sr_dev_inst *sdi)
581 {
582         struct dev_context *devc;
583         uint64_t pre_trigger_samples, post_trigger_samples;
584         uint16_t pre_trigger_bytes, post_trigger_bytes;
585         uint8_t cr;
586
587         devc = sdi->priv;
588         cr = devc->capture_ratio;
589
590         /* Ignore the capture ratio if no trigger is enabled. */
591         if (devc->trigger_type == TRIGGER_TYPE_NONE)
592                 cr = 0;
593
594         pre_trigger_samples = (devc->limit_samples * cr) / 100;
595         post_trigger_samples = (devc->limit_samples * (100 - cr)) / 100;
596
597         /*
598          * Increase the number of post trigger samples by one to compensate the
599          * possible loss of a sample through integer rounding.
600          */
601         if (pre_trigger_samples + post_trigger_samples != devc->limit_samples)
602                 post_trigger_samples++;
603
604         /*
605          * The device requires the number of samples in multiples of 8 which
606          * will also be called sample bytes in the following.
607          */
608         pre_trigger_bytes = pre_trigger_samples / 8;
609         post_trigger_bytes = post_trigger_samples / 8;
610
611         /*
612          * Round up the number of sample bytes to ensure that at least the
613          * requested number of samples will be acquired. Note that due to this
614          * rounding the buffer to store these sample bytes needs to be at least
615          * one sample byte larger than the minimal number of sample bytes
616          * needed to store the requested samples.
617          */
618         if (pre_trigger_samples % 8 != 0)
619                 pre_trigger_bytes++;
620
621         if (post_trigger_samples % 8 != 0)
622                 post_trigger_bytes++;
623
624         sr_info("Pre trigger samples: %" PRIu64 ".", pre_trigger_samples);
625         sr_info("Post trigger samples: %" PRIu64 ".", post_trigger_samples);
626         sr_dbg("Pre trigger sample bytes: %" PRIu16 ".", pre_trigger_bytes);
627         sr_dbg("Post trigger sample bytes: %" PRIu16 ".", post_trigger_bytes);
628
629         devc->pre_trigger_samples = pre_trigger_samples;
630         devc->pre_trigger_bytes = pre_trigger_bytes;
631         devc->post_trigger_bytes = post_trigger_bytes;
632 }
633
634 SR_PRIV int sl2_get_device_info(struct sr_usb_dev_inst usb,
635                 struct device_info *dev_info)
636 {
637         struct drv_context *drvc;
638         uint8_t buffer[PACKET_LENGTH];
639         int ret;
640
641         drvc = di->priv;
642
643         if (!dev_info)
644                 return SR_ERR_ARG;
645
646         if (sr_usb_open(drvc->sr_ctx->libusb_ctx, &usb) != SR_OK)
647                 return SR_ERR;
648
649         /*
650          * Determine if a kernel driver is active on this interface and, if so,
651          * detach it.
652          */
653         if (libusb_kernel_driver_active(usb.devhdl, USB_INTERFACE) == 1) {
654                 ret = libusb_detach_kernel_driver(usb.devhdl,
655                         USB_INTERFACE);
656
657                 if (ret < 0) {
658                         sr_err("Failed to detach kernel driver: %i.",
659                                 libusb_error_name(ret));
660                         libusb_close(usb.devhdl);
661                         return SR_ERR;
662                 }
663         }
664
665         ret = libusb_claim_interface(usb.devhdl, USB_INTERFACE);
666
667         if (ret) {
668                 sr_err("Failed to claim interface: %s.",
669                         libusb_error_name(ret));
670                 libusb_close(usb.devhdl);
671                 return SR_ERR;
672         }
673
674         memset(buffer, 0, sizeof(buffer));
675
676         /*
677          * Reset the device to ensure it is in a proper state to request the
678          * device information.
679          */
680         buffer[0] = CMD_RESET;
681         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
682                 sr_err("Resetting of device failed: %s.",
683                         libusb_error_name(ret));
684                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
685                 libusb_close(usb.devhdl);
686                 return SR_ERR;
687         }
688
689         buffer[0] = CMD_INFO;
690         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
691                 sr_err("Requesting of device information failed: %s.",
692                         libusb_error_name(ret));
693                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
694                 libusb_close(usb.devhdl);
695                 return SR_ERR;
696         }
697
698         if ((ret = sl2_transfer_in(usb.devhdl, buffer)) != PACKET_LENGTH) {
699                 sr_err("Receiving of device information failed: %s.",
700                         libusb_error_name(ret));
701                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
702                 libusb_close(usb.devhdl);
703                 return SR_ERR;
704         }
705
706         memcpy(&(dev_info->serial), buffer + 1, sizeof(uint32_t));
707         dev_info->serial = GUINT32_FROM_LE(dev_info->serial);
708
709         dev_info->fw_ver_major = buffer[5];
710         dev_info->fw_ver_minor = buffer[6];
711
712         buffer[0] = CMD_RESET;
713         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
714                 sr_err("Device reset failed: %s.", libusb_error_name(ret));
715                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
716                 libusb_close(usb.devhdl);
717                 return SR_ERR;
718         }
719
720         /*
721          * Set the device to idle state. If the device is not in idle state it
722          * possibly will reset itself after a few seconds without being used
723          * and thereby close the connection.
724          */
725         buffer[0] = CMD_IDLE;
726         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
727                 sr_err("Failed to set device in idle state: %s.",
728                         libusb_error_name(ret));
729                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
730                 libusb_close(usb.devhdl);
731                 return SR_ERR;
732         }
733
734         ret = libusb_release_interface(usb.devhdl, USB_INTERFACE);
735
736         if (ret < 0) {
737                 sr_err("Failed to release interface: %i.",
738                         libusb_error_name(ret));
739                 libusb_close(usb.devhdl);
740                 return SR_ERR;
741         }
742
743         libusb_close(usb.devhdl);
744
745         return SR_OK;
746 }
747
748 SR_PRIV int sl2_transfer_in(libusb_device_handle *dev_handle, uint8_t *data)
749 {
750         return libusb_control_transfer(dev_handle, USB_REQUEST_TYPE_IN,
751                 USB_HID_SET_REPORT, USB_HID_REPORT_TYPE_FEATURE, USB_INTERFACE,
752                 (unsigned char *)data, PACKET_LENGTH, USB_TIMEOUT);
753 }
754
755 SR_PRIV int sl2_transfer_out(libusb_device_handle *dev_handle, uint8_t *data)
756 {
757         return libusb_control_transfer(dev_handle, USB_REQUEST_TYPE_OUT,
758                 USB_HID_SET_REPORT, USB_HID_REPORT_TYPE_FEATURE, USB_INTERFACE,
759                 (unsigned char *)data, PACKET_LENGTH, USB_TIMEOUT);
760 }