949b2c0454e1b0fce154c53df624acaaad810374
[libsigrok.git] / src / hardware / openbench-logic-sniffer / protocol.c
1 /*
2  * This file is part of the libsigrok project.
3  *
4  * Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
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 <config.h>
21 #include "protocol.h"
22
23
24 struct ols_basic_trigger_desc {
25         uint32_t trigger_mask[NUM_BASIC_TRIGGER_STAGES];
26         uint32_t trigger_value[NUM_BASIC_TRIGGER_STAGES];
27         int num_stages;
28 };
29
30 SR_PRIV int send_shortcommand(struct sr_serial_dev_inst *serial,
31                 uint8_t command)
32 {
33         char buf[1];
34
35         sr_dbg("Sending cmd 0x%.2x.", command);
36         buf[0] = command;
37         if (serial_write_blocking(serial, buf, 1, serial_timeout(serial, 1)) != 1)
38                 return SR_ERR;
39
40         if (serial_drain(serial) != SR_OK)
41                 return SR_ERR;
42
43         return SR_OK;
44 }
45
46 SR_PRIV int send_longcommand(struct sr_serial_dev_inst *serial,
47                 uint8_t command, uint8_t *data)
48 {
49         char buf[5];
50
51         sr_dbg("Sending cmd 0x%.2x data 0x%.2x%.2x%.2x%.2x.", command,
52                         data[0], data[1], data[2], data[3]);
53         buf[0] = command;
54         buf[1] = data[0];
55         buf[2] = data[1];
56         buf[3] = data[2];
57         buf[4] = data[3];
58         if (serial_write_blocking(serial, buf, 5, serial_timeout(serial, 1)) != 5)
59                 return SR_ERR;
60
61         if (serial_drain(serial) != SR_OK)
62                 return SR_ERR;
63
64         return SR_OK;
65 }
66
67 SR_PRIV int ols_send_reset(struct sr_serial_dev_inst *serial)
68 {
69         unsigned int i;
70
71         for (i = 0; i < 5; i++) {
72                 if (send_shortcommand(serial, CMD_RESET) != SR_OK)
73                         return SR_ERR;
74         }
75
76         return SR_OK;
77 }
78
79 /* Configures the channel mask based on which channels are enabled. */
80 SR_PRIV uint32_t ols_channel_mask(const struct sr_dev_inst *sdi)
81 {
82         uint32_t channel_mask = 0;
83         for (const GSList *l = sdi->channels; l; l = l->next) {
84                 struct sr_channel *channel = l->data;
85                 if (channel->enabled)
86                         channel_mask |= 1 << channel->index;
87         }
88
89         return channel_mask;
90 }
91
92 static int convert_trigger(const struct sr_dev_inst *sdi, struct ols_basic_trigger_desc *ols_trigger)
93 {
94         struct sr_trigger *trigger;
95         struct sr_trigger_stage *stage;
96         struct sr_trigger_match *match;
97         const GSList *l, *m;
98         int i;
99
100         ols_trigger->num_stages = 0;
101         for (i = 0; i < NUM_BASIC_TRIGGER_STAGES; i++) {
102                 ols_trigger->trigger_mask[i] = 0;
103                 ols_trigger->trigger_value[i] = 0;
104         }
105
106         if (!(trigger = sr_session_trigger_get(sdi->session)))
107                 return SR_OK;
108
109         ols_trigger->num_stages = g_slist_length(trigger->stages);
110         if (ols_trigger->num_stages > NUM_BASIC_TRIGGER_STAGES) {
111                 sr_err("This device only supports %d trigger stages.",
112                                 NUM_BASIC_TRIGGER_STAGES);
113                 return SR_ERR;
114         }
115
116         for (l = trigger->stages; l; l = l->next) {
117                 stage = l->data;
118                 for (m = stage->matches; m; m = m->next) {
119                         match = m->data;
120                         if (!match->channel->enabled)
121                                 /* Ignore disabled channels with a trigger. */
122                                 continue;
123                         ols_trigger->trigger_mask[stage->stage] |= 1 << match->channel->index;
124                         if (match->match == SR_TRIGGER_ONE)
125                                 ols_trigger->trigger_value[stage->stage] |= 1 << match->channel->index;
126                 }
127         }
128
129         return SR_OK;
130 }
131
132 SR_PRIV struct dev_context *ols_dev_new(void)
133 {
134         struct dev_context *devc;
135
136         devc = g_malloc0(sizeof(struct dev_context));
137         devc->trigger_at_smpl = OLS_NO_TRIGGER;
138
139         return devc;
140 }
141
142 static void ols_channel_new(struct sr_dev_inst *sdi, int num_chan)
143 {
144         struct dev_context *devc = sdi->priv;
145         int i;
146
147         for (i = 0; i < num_chan; i++)
148                 sr_channel_new(sdi, i, SR_CHANNEL_LOGIC, TRUE,
149                                 ols_channel_names[i]);
150
151         devc->max_channels = num_chan;
152 }
153
154 static void ols_metadata_quirks(struct sr_dev_inst *sdi)
155 {
156         struct dev_context *devc;
157         gboolean is_shrimp;
158
159         if (!sdi)
160                 return;
161         devc = sdi->priv;
162         if (!devc)
163                 return;
164
165         is_shrimp = sdi->model && strcmp(sdi->model, "Shrimp1.0") == 0;
166         if (is_shrimp) {
167                 if (!devc->max_channels)
168                         ols_channel_new(sdi, 4);
169                 if (!devc->max_samples)
170                         devc->max_samples = 256 * 1024;
171                 if (!devc->max_samplerate)
172                         devc->max_samplerate = SR_MHZ(20);
173         }
174
175         if (sdi->version && strstr(sdi->version, "FPGA version 3.07"))
176                 devc->device_flags |= DEVICE_FLAG_IS_DEMON_CORE;
177 }
178
179 SR_PRIV struct sr_dev_inst *get_metadata(struct sr_serial_dev_inst *serial)
180 {
181         struct sr_dev_inst *sdi;
182         struct dev_context *devc;
183         uint32_t tmp_int;
184         uint8_t key, type;
185         int delay_ms;
186         GString *tmp_str, *devname, *version;
187         guchar tmp_c;
188
189         sdi = g_malloc0(sizeof(struct sr_dev_inst));
190         sdi->status = SR_ST_INACTIVE;
191         devc = ols_dev_new();
192         sdi->priv = devc;
193
194         devname = g_string_new("");
195         version = g_string_new("");
196
197         key = 0xff;
198         while (key) {
199                 delay_ms = serial_timeout(serial, 1);
200                 if (serial_read_blocking(serial, &key, 1, delay_ms) != 1)
201                         break;
202                 if (key == METADATA_TOKEN_END) {
203                         sr_dbg("Got metadata key 0x00, metadata ends.");
204                         break;
205                 }
206                 type = key >> 5;
207                 switch (type) {
208                 case 0:
209                         /* NULL-terminated string */
210                         tmp_str = g_string_new("");
211                         delay_ms = serial_timeout(serial, 1);
212                         while (serial_read_blocking(serial, &tmp_c, 1, delay_ms) == 1 && tmp_c != '\0')
213                                 g_string_append_c(tmp_str, tmp_c);
214                         sr_dbg("Got metadata token 0x%.2x value '%s'.", key, tmp_str->str);
215                         switch (key) {
216                         case METADATA_TOKEN_DEVICE_NAME:
217                                 /* Device name */
218                                 devname = g_string_append(devname, tmp_str->str);
219                                 break;
220                         case METADATA_TOKEN_FPGA_VERSION:
221                                 /* FPGA firmware version */
222                                 if (version->len)
223                                         g_string_append(version, ", ");
224                                 g_string_append(version, "FPGA version ");
225                                 g_string_append(version, tmp_str->str);
226                                 break;
227                         case METADATA_TOKEN_ANCILLARY_VERSION:
228                                 /* Ancillary version */
229                                 if (version->len)
230                                         g_string_append(version, ", ");
231                                 g_string_append(version, "Ancillary version ");
232                                 g_string_append(version, tmp_str->str);
233                                 break;
234                         default:
235                                 sr_info("ols: unknown token 0x%.2x: '%s'", key, tmp_str->str);
236                                 break;
237                         }
238                         g_string_free(tmp_str, TRUE);
239                         break;
240                 case 1:
241                         /* 32-bit unsigned integer */
242                         delay_ms = serial_timeout(serial, 4);
243                         if (serial_read_blocking(serial, &tmp_int, 4, delay_ms) != 4)
244                                 break;
245                         tmp_int = RB32(&tmp_int);
246                         sr_dbg("Got metadata token 0x%.2x value 0x%.8x.", key, tmp_int);
247                         switch (key) {
248                         case METADATA_TOKEN_NUM_PROBES_LONG:
249                                 /* Number of usable channels */
250                                 ols_channel_new(sdi, tmp_int);
251                                 break;
252                         case METADATA_TOKEN_SAMPLE_MEMORY_BYTES:
253                                 /* Amount of sample memory available (bytes) */
254                                 devc->max_samples = tmp_int;
255                                 break;
256                         case METADATA_TOKEN_DYNAMIC_MEMORY_BYTES:
257                                 /* Amount of dynamic memory available (bytes) */
258                                 /* what is this for? */
259                                 break;
260                         case METADATA_TOKEN_MAX_SAMPLE_RATE_HZ:
261                                 /* Maximum sample rate (Hz) */
262                                 devc->max_samplerate = tmp_int;
263                                 break;
264                         case METADATA_TOKEN_PROTOCOL_VERSION_LONG:
265                                 /* protocol version */
266                                 devc->protocol_version = tmp_int;
267                                 break;
268                         default:
269                                 sr_info("Unknown token 0x%.2x: 0x%.8x.", key, tmp_int);
270                                 break;
271                         }
272                         break;
273                 case 2:
274                         /* 8-bit unsigned integer */
275                         delay_ms = serial_timeout(serial, 1);
276                         if (serial_read_blocking(serial, &tmp_c, 1, delay_ms) != 1)
277                                 break;
278                         sr_dbg("Got metadata token 0x%.2x value 0x%.2x.", key, tmp_c);
279                         switch (key) {
280                         case METADATA_TOKEN_NUM_PROBES_SHORT:
281                                 /* Number of usable channels */
282                                 ols_channel_new(sdi, tmp_c);
283                                 break;
284                         case METADATA_TOKEN_PROTOCOL_VERSION_SHORT:
285                                 /* protocol version */
286                                 devc->protocol_version = tmp_c;
287                                 break;
288                         default:
289                                 sr_info("Unknown token 0x%.2x: 0x%.2x.", key, tmp_c);
290                                 break;
291                         }
292                         break;
293                 default:
294                         /* unknown type */
295                         break;
296                 }
297         }
298
299         sdi->model = devname->str;
300         sdi->version = version->str;
301         g_string_free(devname, FALSE);
302         g_string_free(version, FALSE);
303
304         /* Optionally amend received metadata, model specific quirks. */
305         ols_metadata_quirks(sdi);
306
307         return sdi;
308 }
309
310 SR_PRIV int ols_set_samplerate(const struct sr_dev_inst *sdi,
311                 const uint64_t samplerate)
312 {
313         struct dev_context *devc;
314
315         devc = sdi->priv;
316         if (devc->max_samplerate && samplerate > devc->max_samplerate)
317                 return SR_ERR_SAMPLERATE;
318
319         if (samplerate > CLOCK_RATE) {
320                 sr_info("Enabling demux mode.");
321                 devc->capture_flags |= CAPTURE_FLAG_DEMUX;
322                 devc->capture_flags &= ~CAPTURE_FLAG_NOISE_FILTER;
323                 devc->cur_samplerate_divider = (CLOCK_RATE * 2 / samplerate) - 1;
324         } else {
325                 sr_info("Disabling demux mode.");
326                 devc->capture_flags &= ~CAPTURE_FLAG_DEMUX;
327                 devc->capture_flags |= CAPTURE_FLAG_NOISE_FILTER;
328                 devc->cur_samplerate_divider = (CLOCK_RATE / samplerate) - 1;
329         }
330
331         /* Calculate actual samplerate used and complain if it is different
332          * from the requested.
333          */
334         devc->cur_samplerate = CLOCK_RATE / (devc->cur_samplerate_divider + 1);
335         if (devc->capture_flags & CAPTURE_FLAG_DEMUX)
336                 devc->cur_samplerate *= 2;
337         if (devc->cur_samplerate != samplerate)
338                 sr_info("Can't match samplerate %" PRIu64 ", using %"
339                        PRIu64 ".", samplerate, devc->cur_samplerate);
340
341         return SR_OK;
342 }
343
344 SR_PRIV void abort_acquisition(const struct sr_dev_inst *sdi)
345 {
346         struct sr_serial_dev_inst *serial;
347
348         serial = sdi->conn;
349         ols_send_reset(serial);
350
351         serial_source_remove(sdi->session, serial);
352
353         std_session_send_df_end(sdi);
354 }
355
356 SR_PRIV int ols_receive_data(int fd, int revents, void *cb_data)
357 {
358         struct dev_context *devc;
359         struct sr_dev_inst *sdi;
360         struct sr_serial_dev_inst *serial;
361         struct sr_datafeed_packet packet;
362         struct sr_datafeed_logic logic;
363         uint32_t sample;
364         int num_changroups, offset, j;
365         unsigned int i;
366         unsigned char byte;
367
368         (void)fd;
369
370         sdi = cb_data;
371         serial = sdi->conn;
372         devc = sdi->priv;
373
374         if (devc->num_transfers == 0 && revents == 0) {
375                 /* Ignore timeouts as long as we haven't received anything */
376                 return TRUE;
377         }
378
379         if (devc->num_transfers++ == 0) {
380                 devc->raw_sample_buf = g_try_malloc(devc->limit_samples * 4);
381                 if (!devc->raw_sample_buf) {
382                         sr_err("Sample buffer malloc failed.");
383                         return FALSE;
384                 }
385                 /* fill with 1010... for debugging */
386                 memset(devc->raw_sample_buf, 0x82, devc->limit_samples * 4);
387         }
388
389         num_changroups = 0;
390         for (i = 0x20; i > 0x02; i >>= 1) {
391                 if ((devc->capture_flags & i) == 0) {
392                         num_changroups++;
393                 }
394         }
395
396         if (revents == G_IO_IN && devc->num_samples < devc->limit_samples) {
397                 if (serial_read_nonblocking(serial, &byte, 1) != 1)
398                         return FALSE;
399                 devc->cnt_bytes++;
400
401                 /* Ignore it if we've read enough. */
402                 if (devc->num_samples >= devc->limit_samples)
403                         return TRUE;
404
405                 devc->sample[devc->num_bytes++] = byte;
406                 sr_spew("Received byte 0x%.2x.", byte);
407                 if (devc->num_bytes == num_changroups) {
408                         devc->cnt_samples++;
409                         devc->cnt_samples_rle++;
410                         /*
411                          * Got a full sample. Convert from the OLS's little-endian
412                          * sample to the local format.
413                          */
414                         sample = devc->sample[0] | (devc->sample[1] << 8) \
415                                         | (devc->sample[2] << 16) | (devc->sample[3] << 24);
416                         sr_dbg("Received sample 0x%.*x.", devc->num_bytes * 2, sample);
417                         if (devc->capture_flags & CAPTURE_FLAG_RLE) {
418                                 /*
419                                  * In RLE mode the high bit of the sample is the
420                                  * "count" flag, meaning this sample is the number
421                                  * of times the previous sample occurred.
422                                  */
423                                 if (devc->sample[devc->num_bytes - 1] & 0x80) {
424                                         /* Clear the high bit. */
425                                         sample &= ~(0x80 << (devc->num_bytes - 1) * 8);
426                                         devc->rle_count = sample;
427                                         devc->cnt_samples_rle += devc->rle_count;
428                                         sr_dbg("RLE count: %u.", devc->rle_count);
429                                         devc->num_bytes = 0;
430                                         return TRUE;
431                                 }
432                         }
433                         devc->num_samples += devc->rle_count + 1;
434                         if (devc->num_samples > devc->limit_samples) {
435                                 /* Save us from overrunning the buffer. */
436                                 devc->rle_count -= devc->num_samples - devc->limit_samples;
437                                 devc->num_samples = devc->limit_samples;
438                         }
439
440                         if (num_changroups < 4) {
441                                 /*
442                                  * Some channel groups may have been turned
443                                  * off, to speed up transfer between the
444                                  * hardware and the PC. Expand that here before
445                                  * submitting it over the session bus --
446                                  * whatever is listening on the bus will be
447                                  * expecting a full 32-bit sample, based on
448                                  * the number of channels.
449                                  */
450                                 j = 0;
451                                 memset(devc->tmp_sample, 0, 4);
452                                 for (i = 0; i < 4; i++) {
453                                         if (((devc->capture_flags >> 2) & (1 << i)) == 0) {
454                                                 /*
455                                                  * This channel group was
456                                                  * enabled, copy from received
457                                                  * sample.
458                                                  */
459                                                 devc->tmp_sample[i] = devc->sample[j++];
460                                         } else if (devc->capture_flags & CAPTURE_FLAG_DEMUX && (i > 2)) {
461                                                 /* group 2 & 3 get added to 0 & 1 */
462                                                 devc->tmp_sample[i - 2] = devc->sample[j++];
463                                         }
464                                 }
465                                 memcpy(devc->sample, devc->tmp_sample, 4);
466                                 sr_spew("Expanded sample: 0x%.2hhx%.2hhx%.2hhx%.2hhx ",
467                                         devc->sample[3], devc->sample[2], devc->sample[1], devc->sample[0]);
468                         }
469
470                         /*
471                          * the OLS sends its sample buffer backwards.
472                          * store it in reverse order here, so we can dump
473                          * this on the session bus later.
474                          */
475                         offset = (devc->limit_samples - devc->num_samples) * 4;
476                         for (i = 0; i <= devc->rle_count; i++) {
477                                 memcpy(devc->raw_sample_buf + offset + (i * 4),
478                                        devc->sample, 4);
479                         }
480                         memset(devc->sample, 0, 4);
481                         devc->num_bytes = 0;
482                         devc->rle_count = 0;
483                 }
484         } else {
485                 /*
486                  * This is the main loop telling us a timeout was reached, or
487                  * we've acquired all the samples we asked for -- we're done.
488                  * Send the (properly-ordered) buffer to the frontend.
489                  */
490                 sr_dbg("Received %d bytes, %d samples, %d decompressed samples.",
491                                 devc->cnt_bytes, devc->cnt_samples,
492                                 devc->cnt_samples_rle);
493                 if (devc->trigger_at_smpl != OLS_NO_TRIGGER) {
494                         /*
495                          * A trigger was set up, so we need to tell the frontend
496                          * about it.
497                          */
498                         if (devc->trigger_at_smpl > 0) {
499                                 /* There are pre-trigger samples, send those first. */
500                                 packet.type = SR_DF_LOGIC;
501                                 packet.payload = &logic;
502                                 logic.length = devc->trigger_at_smpl * 4;
503                                 logic.unitsize = 4;
504                                 logic.data = devc->raw_sample_buf +
505                                         (devc->limit_samples - devc->num_samples) * 4;
506                                 sr_session_send(sdi, &packet);
507                         }
508
509                         /* Send the trigger. */
510                         std_session_send_df_trigger(sdi);
511                 }
512
513                 /* Send post-trigger / all captured samples. */
514                 int num_pre_trigger_samples = devc->trigger_at_smpl == OLS_NO_TRIGGER
515                         ? 0 : devc->trigger_at_smpl;
516                 packet.type = SR_DF_LOGIC;
517                 packet.payload = &logic;
518                 logic.length = (devc->num_samples - num_pre_trigger_samples) * 4;
519                 logic.unitsize = 4;
520                 logic.data = devc->raw_sample_buf + (num_pre_trigger_samples +
521                         devc->limit_samples - devc->num_samples) * 4;
522                 sr_session_send(sdi, &packet);
523
524                 g_free(devc->raw_sample_buf);
525
526                 serial_flush(serial);
527                 abort_acquisition(sdi);
528         }
529
530         return TRUE;
531 }
532
533 static int ols_set_basic_trigger_stage(const struct ols_basic_trigger_desc *trigger_desc, struct sr_serial_dev_inst *serial, int stage)
534 {
535         uint8_t cmd, arg[4];
536
537         cmd = CMD_SET_BASIC_TRIGGER_MASK0 + stage * 4;
538         arg[0] = trigger_desc->trigger_mask[stage] & 0xff;
539         arg[1] = (trigger_desc->trigger_mask[stage] >> 8) & 0xff;
540         arg[2] = (trigger_desc->trigger_mask[stage] >> 16) & 0xff;
541         arg[3] = (trigger_desc->trigger_mask[stage] >> 24) & 0xff;
542         if (send_longcommand(serial, cmd, arg) != SR_OK)
543                 return SR_ERR;
544
545         cmd = CMD_SET_BASIC_TRIGGER_VALUE0 + stage * 4;
546         arg[0] = trigger_desc->trigger_value[stage] & 0xff;
547         arg[1] = (trigger_desc->trigger_value[stage] >> 8) & 0xff;
548         arg[2] = (trigger_desc->trigger_value[stage] >> 16) & 0xff;
549         arg[3] = (trigger_desc->trigger_value[stage] >> 24) & 0xff;
550         if (send_longcommand(serial, cmd, arg) != SR_OK)
551                 return SR_ERR;
552
553         cmd = CMD_SET_BASIC_TRIGGER_CONFIG0 + stage * 4;
554         arg[0] = arg[1] = arg[3] = 0x00;
555         arg[2] = stage;
556         if (stage == trigger_desc->num_stages)
557                 /* Last stage, fire when this one matches. */
558                 arg[3] |= TRIGGER_START;
559         if (send_longcommand(serial, cmd, arg) != SR_OK)
560                 return SR_ERR;
561
562         return SR_OK;
563 }
564
565 SR_PRIV int ols_prepare_acquisition(const struct sr_dev_inst *sdi) {
566         int ret;
567         uint8_t arg[4];
568
569         struct dev_context *devc = sdi->priv;
570         struct sr_serial_dev_inst *serial = sdi->conn;
571
572         int num_changroups = 0;
573         uint8_t changroup_mask = 0;
574         uint32_t channel_mask = ols_channel_mask(sdi);
575         for (unsigned int i = 0; i < 4; i++) {
576                 if (channel_mask & (0xff << (i * 8))) {
577                         changroup_mask |= (1 << i);
578                         num_changroups++;
579                 }
580         }
581
582         /*
583          * Limit readcount to prevent reading past the end of the hardware
584          * buffer. Rather read too many samples than too few.
585          */
586         uint32_t samplecount = MIN(devc->max_samples / num_changroups, devc->limit_samples);
587         uint32_t readcount = (samplecount + 3) / 4;
588         uint32_t delaycount;
589
590         /* Basic triggers. */
591         struct ols_basic_trigger_desc basic_trigger_desc;
592         if (convert_trigger(sdi, &basic_trigger_desc) != SR_OK) {
593                 sr_err("Failed to configure channels.");
594                 return SR_ERR;
595         }
596         if (basic_trigger_desc.num_stages > 0) {
597                 /*
598                  * According to http://mygizmos.org/ols/Logic-Sniffer-FPGA-Spec.pdf
599                  * reset command must be send prior each arm command
600                  */
601                 sr_dbg("Send reset command before trigger configure");
602                 if (ols_send_reset(serial) != SR_OK)
603                         return SR_ERR;
604
605                 delaycount = readcount * (1 - devc->capture_ratio / 100.0);
606                 devc->trigger_at_smpl = (readcount - delaycount) * 4 - basic_trigger_desc.num_stages;
607                 for (int i = 0; i <= basic_trigger_desc.num_stages; i++) {
608                         sr_dbg("Setting OLS stage %d trigger.", i);
609                         if ((ret = ols_set_basic_trigger_stage(&basic_trigger_desc, serial, i)) != SR_OK)
610                                 return ret;
611                 }
612         } else {
613                 /* No triggers configured, force trigger on first stage. */
614                 sr_dbg("Forcing trigger at stage 0.");
615                 if ((ret = ols_set_basic_trigger_stage(&basic_trigger_desc, serial, 0)) != SR_OK)
616                         return ret;
617                 delaycount = readcount;
618         }
619
620         /* Samplerate. */
621         sr_dbg("Setting samplerate to %" PRIu64 "Hz (divider %u)",
622                         devc->cur_samplerate, devc->cur_samplerate_divider);
623         arg[0] = devc->cur_samplerate_divider & 0xff;
624         arg[1] = (devc->cur_samplerate_divider & 0xff00) >> 8;
625         arg[2] = (devc->cur_samplerate_divider & 0xff0000) >> 16;
626         arg[3] = 0x00;
627         if (send_longcommand(serial, CMD_SET_DIVIDER, arg) != SR_OK)
628                 return SR_ERR;
629
630         /* Send sample limit and pre/post-trigger capture ratio. */
631         sr_dbg("Setting sample limit %d, trigger point at %d",
632                         (readcount - 1) * 4, (delaycount - 1) * 4);
633
634         if (devc->max_samples > 256 * 1024) {
635                 arg[0] = ((readcount - 1) & 0xff);
636                 arg[1] = ((readcount - 1) & 0xff00) >> 8;
637                 arg[2] = ((readcount - 1) & 0xff0000) >> 16;
638                 arg[3] = ((readcount - 1) & 0xff000000) >> 24;
639                 if (send_longcommand(serial, CMD_CAPTURE_READCOUNT, arg) != SR_OK)
640                         return SR_ERR;
641                 arg[0] = ((delaycount - 1) & 0xff);
642                 arg[1] = ((delaycount - 1) & 0xff00) >> 8;
643                 arg[2] = ((delaycount - 1) & 0xff0000) >> 16;
644                 arg[3] = ((delaycount - 1) & 0xff000000) >> 24;
645                 if (send_longcommand(serial, CMD_CAPTURE_DELAYCOUNT, arg) != SR_OK)
646                         return SR_ERR;
647         } else {
648                 arg[0] = ((readcount - 1) & 0xff);
649                 arg[1] = ((readcount - 1) & 0xff00) >> 8;
650                 arg[2] = ((delaycount - 1) & 0xff);
651                 arg[3] = ((delaycount - 1) & 0xff00) >> 8;
652                 if (send_longcommand(serial, CMD_CAPTURE_SIZE, arg) != SR_OK)
653                         return SR_ERR;
654         }
655
656         /* Flag register. */
657         sr_dbg("Setting intpat %s, extpat %s, RLE %s, noise_filter %s, demux %s, %s clock%s",
658                         devc->capture_flags & CAPTURE_FLAG_INTERNAL_TEST_MODE ? "on": "off",
659                         devc->capture_flags & CAPTURE_FLAG_EXTERNAL_TEST_MODE ? "on": "off",
660                         devc->capture_flags & CAPTURE_FLAG_RLE ? "on" : "off",
661                         devc->capture_flags & CAPTURE_FLAG_NOISE_FILTER ? "on": "off",
662                         devc->capture_flags & CAPTURE_FLAG_DEMUX ? "on" : "off",
663                         devc->capture_flags & CAPTURE_FLAG_CLOCK_EXTERNAL ? "external" : "internal",
664                         devc->capture_flags & CAPTURE_FLAG_CLOCK_EXTERNAL ? (devc->capture_flags & CAPTURE_FLAG_INVERT_EXT_CLOCK
665                                 ? " on falling edge" : "on rising edge") : "");
666
667         /*
668          * Enable/disable OLS channel groups in the flag register according
669          * to the channel mask. 1 means "disable channel".
670          */
671         devc->capture_flags &= ~0x3c;
672         devc->capture_flags |= ~(changroup_mask << 2) & 0x3c;
673
674         /* RLE mode is always zero, for now. */
675
676         arg[0] = devc->capture_flags & 0xff;
677         arg[1] = devc->capture_flags >> 8;
678         arg[2] = arg[3] = 0x00;
679         if (send_longcommand(serial, CMD_SET_FLAGS, arg) != SR_OK)
680                 return SR_ERR;
681
682         return SR_OK;
683 }