+ packet.type = SR_DF_LOGIC;
+ packet.payload = &logic;
+ logic.unitsize = UNIT_SIZE;
+ logic.data = acq->out_packet;
+ logic.length = acq->out_offset;
+
+ samples = acq->out_offset / UNIT_SIZE;
+ last = FALSE;
+
+ /* Cut the packet short if necessary. */
+ if (acq->transferred_samples + samples >= devc->limit_samples) {
+ samples = devc->limit_samples - acq->transferred_samples;
+ logic.length = samples * UNIT_SIZE;
+ last = TRUE;
+ }
+ acq->transferred_samples += samples;
+ acq->out_offset = 0;
+
+ /* Send off logic datafeed packet. */
+ sr_session_send(sdi, &packet);
+
+ return last;
+}
+
+/* Demangle and decompress incoming sample data from the capture buffer.
+ * The data chunk is taken from the acquisition state, and is expected to
+ * contain a multiple of 8 device words.
+ * All data currently in the acquisition buffer will be processed. Packets
+ * of decoded samples are sent off to the session bus whenever the output
+ * buffer becomes full while decoding.
+ */
+static int process_sample_data(const struct sr_dev_inst *sdi)
+{
+ uint64_t sample;
+ uint64_t run_len;
+ uint64_t high_nibbles;
+ uint64_t word;
+ struct dev_context *devc;
+ struct acquisition_state *acq;
+ uint8_t *out_p;
+ uint16_t *slice;
+ size_t expect_len;
+ size_t actual_len;
+ size_t in_words_left;
+ size_t si;
+
+ devc = sdi->priv;
+ acq = devc->acquisition;
+
+ if (acq->mem_addr_done >= acq->mem_addr_stop
+ || acq->transferred_samples >= devc->limit_samples)
+ return SR_OK;
+
+ in_words_left = MIN(acq->mem_addr_stop - acq->mem_addr_done,
+ READ_CHUNK_LEN);
+ expect_len = LWLA1034_MEMBUF_LEN(in_words_left) * sizeof(uint16_t);
+ actual_len = acq->xfer_in->actual_length;
+
+ if (actual_len != expect_len) {
+ sr_err("Received size %lu does not match expected size %lu.",
+ (unsigned long)actual_len, (unsigned long)expect_len);
+ devc->transfer_error = TRUE;
+ return SR_ERR;
+ }
+ acq->mem_addr_done += in_words_left;
+ slice = acq->xfer_buf_in;
+ si = 0; /* word index within slice */
+
+ for (;;) {
+ sample = acq->sample;
+ /* Expand run-length samples into session packet. */
+ for (run_len = acq->run_len; run_len > 0; --run_len) {
+ out_p = &acq->out_packet[acq->out_offset];
+ out_p[0] = sample & 0xFF;
+ out_p[1] = (sample >> 8) & 0xFF;
+ out_p[2] = (sample >> 16) & 0xFF;
+ out_p[3] = (sample >> 24) & 0xFF;
+ out_p[4] = (sample >> 32) & 0xFF;
+ acq->out_offset += UNIT_SIZE;
+
+ /* Send out packet if it is full. */
+ if (acq->out_offset > PACKET_SIZE - UNIT_SIZE)
+ if (send_logic_packet(sdi))
+ return SR_OK; /* sample limit reached */
+ }
+ acq->run_len = 0;
+
+ if (in_words_left == 0)
+ break; /* done with current chunk */
+
+ /* Now work on the current slice. */
+ high_nibbles = LWLA_READ32(&slice[8 * 2]);
+ word = LWLA_READ32(&slice[si * 2]);
+ word |= (high_nibbles << (4 * si + 4)) & ((uint64_t)0xF << 32);
+
+ if (acq->rle == RLE_STATE_DATA) {
+ acq->sample = word & ALL_CHANNELS_MASK;
+ acq->run_len = ((word >> NUM_PROBES) & 1) + 1;
+ if (word & RLE_FLAG_LEN_FOLLOWS)
+ acq->rle = RLE_STATE_LEN;
+ } else {
+ acq->run_len += word << 1;
+ acq->rle = RLE_STATE_DATA;
+ }
+
+ /* Move to next word. */
+ if (++si >= 8) {
+ si = 0;
+ slice += 9 * 2;
+ }
+ --in_words_left;
+ }
+
+ /* Send out partially filled packet if it is the last one. */
+ if (acq->mem_addr_done >= acq->mem_addr_stop && acq->out_offset > 0)
+ send_logic_packet(sdi);
+
+ return SR_OK;
+}
+
+/* Finish an acquisition session. This sends the end packet to the session
+ * bus and removes the listener for asynchronous USB transfers.
+ */
+static void end_acquisition(struct sr_dev_inst *sdi)
+{
+ struct drv_context *drvc;
+ struct dev_context *devc;
+ struct sr_datafeed_packet packet;
+
+ drvc = sdi->driver->priv;
+ devc = sdi->priv;
+
+ if (devc->state == STATE_IDLE)
+ return;
+
+ devc->state = STATE_IDLE;
+
+ /* Remove USB file descriptors from polling. */
+ usb_source_remove(drvc->sr_ctx);
+
+ packet.type = SR_DF_END;
+ sr_session_send(sdi, &packet);
+
+ lwla_free_acquisition_state(devc->acquisition);
+ devc->acquisition = NULL;
+
+ sdi->status = SR_ST_ACTIVE;
+}
+
+/* USB output transfer completion callback.
+ */
+static void receive_transfer_out(struct libusb_transfer *transfer)
+{
+ struct sr_dev_inst *sdi;
+ struct dev_context *devc;
+
+ sdi = transfer->user_data;
+ devc = sdi->priv;
+
+ if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
+ sr_err("Transfer to device failed: %d.", transfer->status);
+ devc->transfer_error = TRUE;
+ return;
+ }
+
+ if (devc->reg_write_pos < devc->reg_write_len) {
+ issue_next_write_reg(sdi);
+ } else {
+ switch (devc->state) {
+ case STATE_START_CAPTURE:
+ devc->state = STATE_STATUS_WAIT;
+ break;
+ case STATE_STATUS_REQUEST:
+ devc->state = STATE_STATUS_RESPONSE;
+ submit_transfer(devc, devc->acquisition->xfer_in);
+ break;
+ case STATE_STOP_CAPTURE:
+ if (sdi->status == SR_ST_ACTIVE)
+ request_capture_length(sdi);
+ else
+ end_acquisition(sdi);
+ break;
+ case STATE_LENGTH_REQUEST:
+ devc->state = STATE_LENGTH_RESPONSE;
+ submit_transfer(devc, devc->acquisition->xfer_in);
+ break;
+ case STATE_READ_PREPARE:
+ request_read_mem(sdi);
+ break;
+ case STATE_READ_REQUEST:
+ devc->state = STATE_READ_RESPONSE;
+ submit_transfer(devc, devc->acquisition->xfer_in);
+ break;
+ case STATE_READ_END:
+ end_acquisition(sdi);
+ break;
+ default:
+ sr_err("Unexpected device state %d.", devc->state);
+ break;
+ }
+ }
+}
+
+/* USB input transfer completion callback.
+ */
+static void receive_transfer_in(struct libusb_transfer *transfer)
+{
+ struct sr_dev_inst *sdi;
+ struct dev_context *devc;
+ struct acquisition_state *acq;
+
+ sdi = transfer->user_data;
+ devc = sdi->priv;
+ acq = devc->acquisition;
+
+ if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
+ sr_err("Transfer from device failed: %d.", transfer->status);
+ devc->transfer_error = TRUE;
+ return;
+ }
+
+ switch (devc->state) {
+ case STATE_STATUS_RESPONSE:
+ process_capture_status(sdi);
+ break;
+ case STATE_LENGTH_RESPONSE:
+ process_capture_length(sdi);
+ break;
+ case STATE_READ_RESPONSE:
+ if (process_sample_data(sdi) == SR_OK
+ && acq->mem_addr_next < acq->mem_addr_stop
+ && acq->transferred_samples < devc->limit_samples)
+ request_read_mem(sdi);
+ else
+ issue_read_end(sdi);
+ break;
+ default:
+ sr_err("Unexpected device state %d.", devc->state);
+ break;
+ }
+}
+
+/* Initialize the LWLA. This downloads a bitstream into the FPGA
+ * and executes a simple device test sequence.
+ */
+SR_PRIV int lwla_init_device(const struct sr_dev_inst *sdi)
+{
+ struct dev_context *devc;
+ int ret;
+ uint32_t value;
+
+ devc = sdi->priv;
+
+ /* Select internal clock if it hasn't been set yet */
+ if (devc->selected_clock_source == CLOCK_SOURCE_NONE)
+ devc->selected_clock_source = CLOCK_SOURCE_INT;
+
+ /* Force reload of bitstream */
+ devc->cur_clock_source = CLOCK_SOURCE_NONE;
+
+ ret = lwla_set_clock_source(sdi);
+
+ if (ret != SR_OK)
+ return ret;
+
+ ret = lwla_write_reg(sdi->conn, REG_CMD_CTRL2, 100);
+ if (ret != SR_OK)
+ return ret;
+
+ ret = lwla_read_reg(sdi->conn, REG_CMD_CTRL1, &value);
+ if (ret != SR_OK)
+ return ret;
+ sr_info("Received test word 0x%08X back.", value);
+ if (value != 0x12345678)
+ return SR_ERR;
+
+ ret = lwla_read_reg(sdi->conn, REG_CMD_CTRL4, &value);
+ if (ret != SR_OK)
+ return ret;
+ sr_info("Received test word 0x%08X back.", value);
+ if (value != 0x12345678)
+ return SR_ERR;
+
+ ret = lwla_read_reg(sdi->conn, REG_CMD_CTRL3, &value);
+ if (ret != SR_OK)
+ return ret;
+ sr_info("Received test word 0x%08X back.", value);
+ if (value != 0x87654321)
+ return SR_ERR;
+
+ return ret;
+}
+
+/* Select the LWLA clock source. If the clock source changed from the
+ * previous setting, this will download a new bitstream to the FPGA.
+ */
+SR_PRIV int lwla_set_clock_source(const struct sr_dev_inst *sdi)
+{
+ struct dev_context *devc;
+ int ret;
+ enum clock_source selected;
+
+ devc = sdi->priv;
+ selected = devc->selected_clock_source;
+
+ if (devc->cur_clock_source != selected) {
+ devc->cur_clock_source = CLOCK_SOURCE_NONE;
+
+ if (selected >= 0 && selected < G_N_ELEMENTS(bitstream_map)) {
+ ret = lwla_send_bitstream(sdi->conn,
+ bitstream_map[selected]);
+ if (ret == SR_OK)
+ devc->cur_clock_source = selected;
+ return ret;
+ }