2 * This file is part of the libsigrok project.
4 * Copyright (C) 2014 Daniel Elstner <daniel.kitta@gmail.com>
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.
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.
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/>.
24 /* Bit mask for the RLE repeat-count-follows flag. */
25 #define RLE_FLAG_LEN_FOLLOWS ((uint64_t)1 << 35)
27 /* Start address of capture status memory area to read. */
28 #define CAP_STAT_ADDR 5
30 /* Number of 64-bit words read from the capture status memory. */
31 #define CAP_STAT_LEN 5
33 /* The bitstream filenames are indexed by the clock_config enumeration.
35 static const char bitstream_map[][32] = {
36 "sysclk-lwla1034-off.rbf",
37 "sysclk-lwla1034-int.rbf",
38 "sysclk-lwla1034-extpos.rbf",
39 "sysclk-lwla1034-extneg.rbf",
42 /* Submit an already filled-in USB transfer.
44 static int submit_transfer(struct dev_context *devc,
45 struct libusb_transfer *xfer)
49 ret = libusb_submit_transfer(xfer);
52 sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
53 devc->transfer_error = TRUE;
60 /* Set up the LWLA in preparation for an acquisition session.
62 static int capture_setup(const struct sr_dev_inst *sdi)
64 struct dev_context *devc;
65 struct acquisition_state *acq;
66 uint64_t divider_count;
67 uint64_t trigger_mask;
68 uint64_t memory_limit;
69 uint16_t command[3 + (10 * 4)];
72 acq = devc->acquisition;
74 command[0] = LWLA_WORD(CMD_CAP_SETUP);
75 command[1] = LWLA_WORD(0); /* address */
76 command[2] = LWLA_WORD(10); /* length */
78 command[3] = LWLA_WORD_0(devc->channel_mask);
79 command[4] = LWLA_WORD_1(devc->channel_mask);
80 command[5] = LWLA_WORD_2(devc->channel_mask);
81 command[6] = LWLA_WORD_3(devc->channel_mask);
83 /* Set the clock divide counter maximum for samplerates of up to
84 * 100 MHz. At the highest samplerate of 125 MHz the clock divider
87 if (!acq->bypass_clockdiv && devc->samplerate > 0)
88 divider_count = SR_MHZ(100) / devc->samplerate - 1;
92 command[7] = LWLA_WORD_0(divider_count);
93 command[8] = LWLA_WORD_1(divider_count);
94 command[9] = LWLA_WORD_2(divider_count);
95 command[10] = LWLA_WORD_3(divider_count);
97 command[11] = LWLA_WORD_0(devc->trigger_values);
98 command[12] = LWLA_WORD_1(devc->trigger_values);
99 command[13] = LWLA_WORD_2(devc->trigger_values);
100 command[14] = LWLA_WORD_3(devc->trigger_values);
102 command[15] = LWLA_WORD_0(devc->trigger_edge_mask);
103 command[16] = LWLA_WORD_1(devc->trigger_edge_mask);
104 command[17] = LWLA_WORD_2(devc->trigger_edge_mask);
105 command[18] = LWLA_WORD_3(devc->trigger_edge_mask);
107 trigger_mask = devc->trigger_mask;
108 /* Set bits to select external TRG input edge. */
109 if (devc->cfg_trigger_source == TRIGGER_EXT_TRG)
110 switch (devc->cfg_trigger_slope) {
112 trigger_mask |= (uint64_t)1 << 35;
115 trigger_mask |= (uint64_t)1 << 34;
119 command[19] = LWLA_WORD_0(trigger_mask);
120 command[20] = LWLA_WORD_1(trigger_mask);
121 command[21] = LWLA_WORD_2(trigger_mask);
122 command[22] = LWLA_WORD_3(trigger_mask);
124 /* Set the capture memory full threshold. This is slightly less
125 * than the actual maximum, most likely in order to compensate for
128 memory_limit = MEMORY_DEPTH - 16;
130 command[23] = LWLA_WORD_0(memory_limit);
131 command[24] = LWLA_WORD_1(memory_limit);
132 command[25] = LWLA_WORD_2(memory_limit);
133 command[26] = LWLA_WORD_3(memory_limit);
135 /* Fill remaining words with zeroes. */
136 memset(&command[27], 0, sizeof(command) - 27 * sizeof(command[0]));
138 return lwla_send_command(sdi->conn, command, ARRAY_SIZE(command));
141 /* Issue a register write command as an asynchronous USB transfer.
143 static int issue_write_reg(const struct sr_dev_inst *sdi,
144 unsigned int reg, unsigned int value)
146 struct dev_context *devc;
147 struct acquisition_state *acq;
150 acq = devc->acquisition;
152 acq->xfer_buf_out[0] = LWLA_WORD(CMD_WRITE_REG);
153 acq->xfer_buf_out[1] = LWLA_WORD(reg);
154 acq->xfer_buf_out[2] = LWLA_WORD_0(value);
155 acq->xfer_buf_out[3] = LWLA_WORD_1(value);
157 acq->xfer_out->length = 4 * sizeof(uint16_t);
159 return submit_transfer(devc, acq->xfer_out);
162 /* Issue a register write command as an asynchronous USB transfer for the
163 * next register/value pair of the currently active register write sequence.
165 static int issue_next_write_reg(const struct sr_dev_inst *sdi)
167 struct dev_context *devc;
168 struct regval_pair *regval;
173 if (devc->reg_write_pos >= devc->reg_write_len) {
174 sr_err("Already written all registers in sequence.");
177 regval = &devc->reg_write_seq[devc->reg_write_pos];
179 ret = issue_write_reg(sdi, regval->reg, regval->val);
183 ++devc->reg_write_pos;
187 /* Issue a capture status request as an asynchronous USB transfer.
189 static void request_capture_status(const struct sr_dev_inst *sdi)
191 struct dev_context *devc;
192 struct acquisition_state *acq;
195 acq = devc->acquisition;
197 acq->xfer_buf_out[0] = LWLA_WORD(CMD_CAP_STATUS);
198 acq->xfer_buf_out[1] = LWLA_WORD(CAP_STAT_ADDR);
199 acq->xfer_buf_out[2] = LWLA_WORD(CAP_STAT_LEN);
201 acq->xfer_out->length = 3 * sizeof(uint16_t);
203 if (submit_transfer(devc, acq->xfer_out) == SR_OK)
204 devc->state = STATE_STATUS_REQUEST;
207 /* Issue a request for the capture buffer fill level as
208 * an asynchronous USB transfer.
210 static void request_capture_length(const struct sr_dev_inst *sdi)
212 struct dev_context *devc;
213 struct acquisition_state *acq;
216 acq = devc->acquisition;
218 acq->xfer_buf_out[0] = LWLA_WORD(CMD_READ_REG);
219 acq->xfer_buf_out[1] = LWLA_WORD(REG_MEM_FILL);
221 acq->xfer_out->length = 2 * sizeof(uint16_t);
223 if (submit_transfer(devc, acq->xfer_out) == SR_OK)
224 devc->state = STATE_LENGTH_REQUEST;
227 /* Initiate the capture memory read operation: Reset the acquisition state
228 * and start a sequence of register writes in order to set up the device for
229 * reading from the capture buffer.
231 static void issue_read_start(const struct sr_dev_inst *sdi)
233 struct dev_context *devc;
234 struct acquisition_state *acq;
235 struct regval_pair *regvals;
238 acq = devc->acquisition;
240 /* Reset RLE state. */
241 acq->rle = RLE_STATE_DATA;
245 acq->samples_done = 0;
247 /* For some reason, the start address is 4 rather than 0. */
248 acq->mem_addr_done = 4;
249 acq->mem_addr_next = 4;
250 acq->mem_addr_stop = acq->mem_addr_fill;
252 /* Sample position in the packet output buffer. */
255 regvals = devc->reg_write_seq;
257 regvals[0].reg = REG_DIV_BYPASS;
260 regvals[1].reg = REG_MEM_CTRL2;
263 regvals[2].reg = REG_MEM_CTRL4;
266 devc->reg_write_pos = 0;
267 devc->reg_write_len = 3;
269 if (issue_next_write_reg(sdi) == SR_OK)
270 devc->state = STATE_READ_PREPARE;
273 /* Issue a command as an asynchronous USB transfer which returns the device
274 * to normal state after a read operation. Sets a new device context state
277 static void issue_read_end(const struct sr_dev_inst *sdi)
279 struct dev_context *devc;
283 if (issue_write_reg(sdi, REG_DIV_BYPASS, 0) == SR_OK)
284 devc->state = STATE_READ_END;
287 /* Decode an incoming response to a buffer fill level request and act on it
288 * as appropriate. Note that this function changes the device context state.
290 static void process_capture_length(const struct sr_dev_inst *sdi)
292 struct dev_context *devc;
293 struct acquisition_state *acq;
296 acq = devc->acquisition;
298 if (acq->xfer_in->actual_length != 4) {
299 sr_err("Received size %d doesn't match expected size 4.",
300 acq->xfer_in->actual_length);
301 devc->transfer_error = TRUE;
304 acq->mem_addr_fill = LWLA_TO_UINT32(acq->xfer_buf_in[0]);
306 sr_dbg("%zu words in capture buffer.", acq->mem_addr_fill);
308 if (acq->mem_addr_fill > 0 && !devc->cancel_requested)
309 issue_read_start(sdi);
314 /* Initiate a sequence of register write commands with the effect of
315 * cancelling a running capture operation. This sets a new device state
316 * if issuing the first command succeeds.
318 static void issue_stop_capture(const struct sr_dev_inst *sdi)
320 struct dev_context *devc;
321 struct regval_pair *regvals;
325 if (devc->stopping_in_progress)
328 regvals = devc->reg_write_seq;
330 regvals[0].reg = REG_LONG_ADDR;
333 regvals[1].reg = REG_LONG_LOW;
336 regvals[2].reg = REG_LONG_HIGH;
339 regvals[3].reg = REG_LONG_STROBE;
342 regvals[4].reg = REG_DIV_BYPASS;
345 devc->reg_write_pos = 0;
346 devc->reg_write_len = 5;
348 if (issue_next_write_reg(sdi) == SR_OK) {
349 devc->stopping_in_progress = TRUE;
350 devc->state = STATE_STOP_CAPTURE;
354 /* Decode an incoming capture status response and act on it as appropriate.
355 * Note that this function changes the device state.
357 static void process_capture_status(const struct sr_dev_inst *sdi)
360 struct dev_context *devc;
361 struct acquisition_state *acq;
362 unsigned int mem_fill;
366 acq = devc->acquisition;
368 if (acq->xfer_in->actual_length != CAP_STAT_LEN * 8) {
369 sr_err("Received size %d doesn't match expected size %d.",
370 acq->xfer_in->actual_length, CAP_STAT_LEN * 8);
371 devc->transfer_error = TRUE;
375 /* TODO: Find out the actual bit width of these fields as stored
376 * in the FPGA. These fields are definitely less than 64 bit wide
377 * internally, and the unused bits occasionally even contain garbage.
379 mem_fill = LWLA_TO_UINT32(acq->xfer_buf_in[0]);
380 duration = LWLA_TO_UINT32(acq->xfer_buf_in[4]);
381 flags = LWLA_TO_UINT32(acq->xfer_buf_in[8]) & STATUS_FLAG_MASK;
383 /* The LWLA1034 runs at 125 MHz if the clock divider is bypassed.
384 * However, the time base used for the duration is apparently not
385 * adjusted for this "boost" mode. Whereas normally the duration
386 * unit is 1 ms, it is 0.8 ms when the clock divider is bypassed.
387 * As 0.8 = 100 MHz / 125 MHz, it seems that the internal cycle
388 * counter period is the same as at the 100 MHz setting.
390 if (acq->bypass_clockdiv)
391 acq->duration_now = duration * 4 / 5;
393 acq->duration_now = duration;
395 sr_spew("Captured %u words, %" PRIu64 " ms, flags 0x%02X.",
396 mem_fill, acq->duration_now, flags);
398 if ((flags & STATUS_TRIGGERED) > (acq->capture_flags & STATUS_TRIGGERED))
399 sr_info("Capture triggered.");
401 acq->capture_flags = flags;
403 if (acq->duration_now >= acq->duration_max) {
404 sr_dbg("Time limit reached, stopping capture.");
405 issue_stop_capture(sdi);
408 devc->state = STATE_STATUS_WAIT;
410 if ((acq->capture_flags & STATUS_TRIGGERED) == 0) {
411 sr_spew("Waiting for trigger.");
412 } else if ((acq->capture_flags & STATUS_MEM_AVAIL) == 0) {
413 sr_dbg("Capture memory filled.");
414 request_capture_length(sdi);
415 } else if ((acq->capture_flags & STATUS_CAPTURING) != 0) {
416 sr_spew("Sampling in progress.");
420 /* Issue a capture buffer read request as an asynchronous USB transfer.
421 * The address and size of the memory area to read are derived from the
422 * current acquisition state.
424 static void request_read_mem(const struct sr_dev_inst *sdi)
426 struct dev_context *devc;
427 struct acquisition_state *acq;
431 acq = devc->acquisition;
433 if (acq->mem_addr_next >= acq->mem_addr_stop)
436 /* Always read a multiple of 8 device words. */
437 count = (acq->mem_addr_stop - acq->mem_addr_next + 7) / 8 * 8;
438 count = MIN(count, READ_CHUNK_LEN);
440 acq->xfer_buf_out[0] = LWLA_WORD(CMD_READ_MEM);
441 acq->xfer_buf_out[1] = LWLA_WORD_0(acq->mem_addr_next);
442 acq->xfer_buf_out[2] = LWLA_WORD_1(acq->mem_addr_next);
443 acq->xfer_buf_out[3] = LWLA_WORD_0(count);
444 acq->xfer_buf_out[4] = LWLA_WORD_1(count);
446 acq->xfer_out->length = 5 * sizeof(uint16_t);
448 if (submit_transfer(devc, acq->xfer_out) == SR_OK) {
449 acq->mem_addr_next += count;
450 devc->state = STATE_READ_REQUEST;
454 /* Demangle and decompress incoming sample data from the capture buffer.
455 * The data chunk is taken from the acquisition state, and is expected to
456 * contain a multiple of 8 device words.
457 * All data currently in the acquisition buffer will be processed. Packets
458 * of decoded samples are sent off to the session bus whenever the output
459 * buffer becomes full while decoding.
461 static int process_sample_data(const struct sr_dev_inst *sdi)
464 uint64_t high_nibbles;
466 struct dev_context *devc;
467 struct acquisition_state *acq;
470 struct sr_datafeed_packet packet;
471 struct sr_datafeed_logic logic;
474 size_t out_max_samples;
475 size_t out_run_samples;
477 size_t in_words_left;
481 acq = devc->acquisition;
483 if (acq->mem_addr_done >= acq->mem_addr_stop
484 || acq->samples_done >= acq->samples_max)
487 in_words_left = MIN(acq->mem_addr_stop - acq->mem_addr_done,
489 expect_len = LWLA1034_MEMBUF_LEN(in_words_left) * sizeof(uint32_t);
490 actual_len = acq->xfer_in->actual_length;
492 if (actual_len != expect_len) {
493 sr_err("Received size %zu does not match expected size %zu.",
494 actual_len, expect_len);
495 devc->transfer_error = TRUE;
498 acq->mem_addr_done += in_words_left;
500 /* Prepare session packet. */
501 packet.type = SR_DF_LOGIC;
502 packet.payload = &logic;
503 logic.unitsize = UNIT_SIZE;
504 logic.data = acq->out_packet;
506 slice = acq->xfer_buf_in;
507 si = 0; /* word index within slice */
510 /* Calculate number of samples to write into packet. */
511 out_max_samples = MIN(acq->samples_max - acq->samples_done,
512 PACKET_LENGTH - acq->out_index);
513 out_run_samples = MIN(acq->run_len, out_max_samples);
515 /* Expand run-length samples into session packet. */
516 sample = acq->sample;
517 out_p = &acq->out_packet[acq->out_index * UNIT_SIZE];
519 for (ri = 0; ri < out_run_samples; ++ri) {
520 out_p[0] = sample & 0xFF;
521 out_p[1] = (sample >> 8) & 0xFF;
522 out_p[2] = (sample >> 16) & 0xFF;
523 out_p[3] = (sample >> 24) & 0xFF;
524 out_p[4] = (sample >> 32) & 0xFF;
527 acq->run_len -= out_run_samples;
528 acq->out_index += out_run_samples;
529 acq->samples_done += out_run_samples;
531 /* Packet full or sample count limit reached? */
532 if (out_run_samples == out_max_samples) {
533 logic.length = acq->out_index * UNIT_SIZE;
534 sr_session_send(sdi, &packet);
537 if (acq->samples_done >= acq->samples_max)
538 return SR_OK; /* sample limit reached */
539 if (acq->run_len > 0)
540 continue; /* need another packet */
543 if (in_words_left == 0)
544 break; /* done with current chunk */
546 /* Now work on the current slice. */
547 high_nibbles = LWLA_TO_UINT32(slice[8]);
548 word = LWLA_TO_UINT32(slice[si]);
549 word |= (high_nibbles << (4 * si + 4)) & ((uint64_t)0xF << 32);
551 if (acq->rle == RLE_STATE_DATA) {
552 acq->sample = word & ALL_CHANNELS_MASK;
553 acq->run_len = ((word >> NUM_CHANNELS) & 1) + 1;
554 if (word & RLE_FLAG_LEN_FOLLOWS)
555 acq->rle = RLE_STATE_LEN;
557 acq->run_len += word << 1;
558 acq->rle = RLE_STATE_DATA;
561 /* Move to next word. */
568 /* Send out partially filled packet if this was the last chunk. */
569 if (acq->mem_addr_done >= acq->mem_addr_stop && acq->out_index > 0) {
570 logic.length = acq->out_index * UNIT_SIZE;
571 sr_session_send(sdi, &packet);
577 /* Finish an acquisition session. This sends the end packet to the session
578 * bus and removes the listener for asynchronous USB transfers.
580 static void end_acquisition(struct sr_dev_inst *sdi)
582 struct drv_context *drvc;
583 struct dev_context *devc;
584 struct sr_datafeed_packet packet;
586 drvc = sdi->driver->context;
589 if (devc->state == STATE_IDLE)
592 devc->state = STATE_IDLE;
594 /* Remove USB file descriptors from polling. */
595 usb_source_remove(sdi->session, drvc->sr_ctx);
597 packet.type = SR_DF_END;
598 sr_session_send(sdi, &packet);
600 lwla_free_acquisition_state(devc->acquisition);
601 devc->acquisition = NULL;
602 devc->cancel_requested = FALSE;
605 /* USB output transfer completion callback.
607 static void LIBUSB_CALL receive_transfer_out(struct libusb_transfer *transfer)
609 struct sr_dev_inst *sdi;
610 struct dev_context *devc;
612 sdi = transfer->user_data;
615 if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
616 sr_err("Transfer to device failed: %d.", transfer->status);
617 devc->transfer_error = TRUE;
621 if (devc->reg_write_pos < devc->reg_write_len) {
622 issue_next_write_reg(sdi);
624 switch (devc->state) {
625 case STATE_START_CAPTURE:
626 devc->state = STATE_STATUS_WAIT;
628 case STATE_STATUS_REQUEST:
629 devc->state = STATE_STATUS_RESPONSE;
630 submit_transfer(devc, devc->acquisition->xfer_in);
632 case STATE_STOP_CAPTURE:
633 if (!devc->cancel_requested)
634 request_capture_length(sdi);
636 end_acquisition(sdi);
638 case STATE_LENGTH_REQUEST:
639 devc->state = STATE_LENGTH_RESPONSE;
640 submit_transfer(devc, devc->acquisition->xfer_in);
642 case STATE_READ_PREPARE:
643 request_read_mem(sdi);
645 case STATE_READ_REQUEST:
646 devc->state = STATE_READ_RESPONSE;
647 submit_transfer(devc, devc->acquisition->xfer_in);
650 end_acquisition(sdi);
653 sr_err("Unexpected device state %d.", devc->state);
659 /* USB input transfer completion callback.
661 static void LIBUSB_CALL receive_transfer_in(struct libusb_transfer *transfer)
663 struct sr_dev_inst *sdi;
664 struct dev_context *devc;
665 struct acquisition_state *acq;
667 sdi = transfer->user_data;
669 acq = devc->acquisition;
671 if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
672 sr_err("Transfer from device failed: %d.", transfer->status);
673 devc->transfer_error = TRUE;
677 switch (devc->state) {
678 case STATE_STATUS_RESPONSE:
679 process_capture_status(sdi);
681 case STATE_LENGTH_RESPONSE:
682 process_capture_length(sdi);
684 case STATE_READ_RESPONSE:
685 if (process_sample_data(sdi) == SR_OK
686 && acq->mem_addr_next < acq->mem_addr_stop
687 && acq->samples_done < acq->samples_max)
688 request_read_mem(sdi);
693 sr_err("Unexpected device state %d.", devc->state);
698 /* Initialize the LWLA. This downloads a bitstream into the FPGA
699 * and executes a simple device test sequence.
701 SR_PRIV int lwla_init_device(const struct sr_dev_inst *sdi)
703 struct dev_context *devc;
709 /* Force reload of bitstream */
710 devc->cur_clock_config = CONF_CLOCK_NONE;
712 ret = lwla_set_clock_config(sdi);
717 ret = lwla_write_reg(sdi->conn, REG_LONG_ADDR, 100);
721 ret = lwla_read_reg(sdi->conn, REG_LONG_STROBE, &value);
724 sr_dbg("Received test word 0x%08X back.", value);
725 if (value != 0x12345678)
728 ret = lwla_read_reg(sdi->conn, REG_LONG_HIGH, &value);
731 sr_dbg("Received test word 0x%08X back.", value);
732 if (value != 0x12345678)
735 ret = lwla_read_reg(sdi->conn, REG_LONG_LOW, &value);
738 sr_dbg("Received test word 0x%08X back.", value);
739 if (value != 0x87654321)
745 /* Select the LWLA clock configuration. If the clock source changed from
746 * the previous setting, this will download a new bitstream to the FPGA.
748 SR_PRIV int lwla_set_clock_config(const struct sr_dev_inst *sdi)
750 struct dev_context *devc;
751 struct drv_context *drvc;
753 enum clock_config choice;
756 drvc = sdi->driver->context;
758 if (sdi->status == SR_ST_INACTIVE)
759 choice = CONF_CLOCK_NONE;
760 else if (devc->cfg_clock_source == CLOCK_INTERNAL)
761 choice = CONF_CLOCK_INT;
762 else if (devc->cfg_clock_edge == EDGE_POSITIVE)
763 choice = CONF_CLOCK_EXT_RISE;
765 choice = CONF_CLOCK_EXT_FALL;
767 if (choice != devc->cur_clock_config) {
768 devc->cur_clock_config = CONF_CLOCK_NONE;
769 ret = lwla_send_bitstream(drvc->sr_ctx, sdi->conn,
770 bitstream_map[choice]);
772 devc->cur_clock_config = choice;
778 /* Configure the LWLA in preparation for an acquisition session.
780 SR_PRIV int lwla_setup_acquisition(const struct sr_dev_inst *sdi)
782 struct dev_context *devc;
783 struct sr_usb_dev_inst *usb;
784 struct acquisition_state *acq;
785 struct regval_pair regvals[7];
790 acq = devc->acquisition;
792 if (devc->limit_msec > 0) {
793 acq->duration_max = devc->limit_msec;
794 sr_info("Acquisition time limit %" PRIu64 " ms.",
797 acq->duration_max = MAX_LIMIT_MSEC;
799 if (devc->limit_samples > 0) {
800 acq->samples_max = devc->limit_samples;
801 sr_info("Acquisition sample count limit %" PRIu64 ".",
802 devc->limit_samples);
804 acq->samples_max = MAX_LIMIT_SAMPLES;
806 if (devc->cfg_clock_source == CLOCK_INTERNAL) {
807 sr_info("Internal clock, samplerate %" PRIu64 ".",
809 if (devc->samplerate == 0)
811 /* At 125 MHz, the clock divider is bypassed. */
812 acq->bypass_clockdiv = (devc->samplerate > SR_MHZ(100));
814 /* If only one of the limits is set, derive the other one. */
815 if (devc->limit_msec == 0 && devc->limit_samples > 0)
816 acq->duration_max = devc->limit_samples
817 * 1000 / devc->samplerate + 1;
818 else if (devc->limit_samples == 0 && devc->limit_msec > 0)
819 acq->samples_max = devc->limit_msec
820 * devc->samplerate / 1000;
822 acq->bypass_clockdiv = TRUE;
824 if (devc->cfg_clock_edge == EDGE_NEGATIVE)
825 sr_info("External clock, falling edge.");
827 sr_info("External clock, rising edge.");
830 regvals[0].reg = REG_MEM_CTRL2;
833 regvals[1].reg = REG_MEM_CTRL2;
836 regvals[2].reg = REG_LONG_ADDR;
839 regvals[3].reg = REG_LONG_LOW;
840 regvals[3].val = 0x74;
842 regvals[4].reg = REG_LONG_HIGH;
845 regvals[5].reg = REG_LONG_STROBE;
848 regvals[6].reg = REG_DIV_BYPASS;
849 regvals[6].val = acq->bypass_clockdiv;
851 ret = lwla_write_regs(usb, regvals, ARRAY_SIZE(regvals));
855 return capture_setup(sdi);
858 /* Start the capture operation on the LWLA device. Beginning with this
859 * function, all USB transfers will be asynchronous until the end of the
860 * acquisition session.
862 SR_PRIV int lwla_start_acquisition(const struct sr_dev_inst *sdi)
864 struct dev_context *devc;
865 struct sr_usb_dev_inst *usb;
866 struct acquisition_state *acq;
867 struct regval_pair *regvals;
871 acq = devc->acquisition;
873 acq->duration_now = 0;
874 acq->mem_addr_fill = 0;
875 acq->capture_flags = 0;
877 libusb_fill_bulk_transfer(acq->xfer_out, usb->devhdl, EP_COMMAND,
878 (unsigned char *)acq->xfer_buf_out, 0,
879 &receive_transfer_out,
880 (struct sr_dev_inst *)sdi, USB_TIMEOUT_MS);
882 libusb_fill_bulk_transfer(acq->xfer_in, usb->devhdl, EP_REPLY,
883 (unsigned char *)acq->xfer_buf_in,
884 sizeof acq->xfer_buf_in,
885 &receive_transfer_in,
886 (struct sr_dev_inst *)sdi, USB_TIMEOUT_MS);
888 regvals = devc->reg_write_seq;
890 regvals[0].reg = REG_LONG_ADDR;
893 regvals[1].reg = REG_LONG_LOW;
896 regvals[2].reg = REG_LONG_HIGH;
899 regvals[3].reg = REG_LONG_STROBE;
902 devc->reg_write_pos = 0;
903 devc->reg_write_len = 4;
905 devc->state = STATE_START_CAPTURE;
907 return issue_next_write_reg(sdi);
910 /* Allocate an acquisition state object.
912 SR_PRIV struct acquisition_state *lwla_alloc_acquisition_state(void)
914 struct acquisition_state *acq;
916 acq = g_malloc0(sizeof(struct acquisition_state));
918 acq->xfer_in = libusb_alloc_transfer(0);
920 sr_err("Transfer malloc failed.");
925 acq->xfer_out = libusb_alloc_transfer(0);
926 if (!acq->xfer_out) {
927 sr_err("Transfer malloc failed.");
928 libusb_free_transfer(acq->xfer_in);
936 /* Deallocate an acquisition state object.
938 SR_PRIV void lwla_free_acquisition_state(struct acquisition_state *acq)
941 libusb_free_transfer(acq->xfer_out);
942 libusb_free_transfer(acq->xfer_in);
947 /* USB I/O source callback.
949 SR_PRIV int lwla_receive_data(int fd, int revents, void *cb_data)
951 struct sr_dev_inst *sdi;
952 struct dev_context *devc;
953 struct drv_context *drvc;
961 drvc = sdi->driver->context;
966 /* No timeout: return immediately. */
970 ret = libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx,
973 sr_err("Event handling failed: %s.", libusb_error_name(ret));
975 /* If no event flags are set the timeout must have expired. */
976 if (revents == 0 && devc->state == STATE_STATUS_WAIT) {
977 if (devc->cancel_requested)
978 issue_stop_capture(sdi);
980 request_capture_status(sdi);
983 /* Check if an error occurred on a transfer. */
984 if (devc->transfer_error)
985 end_acquisition(sdi);