+ drvc = di->priv;
+ devc = sdi->priv;
+ usb = sdi->conn;
+
+ devc->cb_data = cb_data;
+ devc->num_samples = 0;
+
+ /* Send header packet to the session bus. */
+ std_session_send_df_header(cb_data, LOG_PREFIX);
+
+ if (devc->data_source == DATA_SOURCE_LIVE) {
+ /* Force configuration. */
+ kecheng_kc_330b_configure(sdi);
+
+ if (kecheng_kc_330b_status_get(sdi, &ret) != SR_OK)
+ return SR_ERR;
+ if (ret != DEVICE_ACTIVE) {
+ sr_err("Device is inactive");
+ /* Still continue though, since the device will
+ * just return 30.0 until the user hits the button
+ * on the device -- and then start feeding good
+ * samples back. */
+ }
+ } else {
+ if (kecheng_kc_330b_log_info_get(sdi, buf) != SR_OK)
+ return SR_ERR;
+ stored_mqflags = buf[4] ? SR_MQFLAG_SPL_TIME_WEIGHT_S : SR_MQFLAG_SPL_TIME_WEIGHT_F;
+ stored_mqflags |= buf[5] ? SR_MQFLAG_SPL_FREQ_WEIGHT_C : SR_MQFLAG_SPL_FREQ_WEIGHT_A;
+ devc->stored_samples = (buf[7] << 8) | buf[8];
+ if (devc->stored_samples == 0) {
+ /* Notify frontend of empty log by sending start/end packets. */
+ packet.type = SR_DF_END;
+ sr_session_send(cb_data, &packet);
+ return SR_OK;
+ }
+
+ if (devc->limit_samples && devc->limit_samples < devc->stored_samples)
+ devc->stored_samples = devc->limit_samples;
+
+ si = kecheng_kc_330b_sample_intervals[buf[1]];
+ rational[0] = g_variant_new_uint64(si[0]);
+ rational[1] = g_variant_new_uint64(si[1]);
+ gvar = g_variant_new_tuple(rational, 2);
+ src = sr_config_new(SR_CONF_SAMPLE_INTERVAL, gvar);
+ packet.type = SR_DF_META;
+ packet.payload = &meta;
+ meta.config = g_slist_append(NULL, src);
+ sr_session_send(devc->cb_data, &packet);
+ g_free(src);
+ }
+
+ if (!(devc->xfer = libusb_alloc_transfer(0)))
+ return SR_ERR;
+
+ usb_source_add(drvc->sr_ctx, 10,
+ kecheng_kc_330b_handle_events, (void *)sdi);
+
+ if (devc->data_source == DATA_SOURCE_LIVE) {
+ buf[0] = CMD_GET_LIVE_SPL;
+ buf_len = 1;
+ devc->state = LIVE_SPL_WAIT;
+ devc->last_live_request = g_get_monotonic_time() / 1000;
+ req_len = 3;
+ } else {
+ buf[0] = CMD_GET_LOG_DATA;
+ buf[1] = 0;
+ buf[2] = 0;
+ buf_len = 4;
+ devc->state = LOG_DATA_WAIT;
+ if (devc->stored_samples < 63)
+ buf[3] = devc->stored_samples;
+ else
+ buf[3] = 63;
+ /* Command ack byte + 2 bytes per sample. */
+ req_len = 1 + buf[3] * 2;
+ }
+
+ ret = libusb_bulk_transfer(usb->devhdl, EP_OUT, buf, buf_len, &len, 5);
+ if (ret != 0 || len != 1) {
+ sr_dbg("Failed to start acquisition: %s", libusb_error_name(ret));
+ libusb_free_transfer(devc->xfer);
+ return SR_ERR;
+ }
+
+ libusb_fill_bulk_transfer(devc->xfer, usb->devhdl, EP_IN, devc->buf,
+ req_len, kecheng_kc_330b_receive_transfer, (void *)sdi, 15);
+ if (libusb_submit_transfer(devc->xfer) != 0) {
+ libusb_free_transfer(devc->xfer);
+ return SR_ERR;
+ }