]> sigrok.org Git - libsigrok.git/blobdiff - hardware/saleae-logic16/protocol.c
Add struct sr_session parameter to all session source backends.
[libsigrok.git] / hardware / saleae-logic16 / protocol.c
index 048fd19c2c7baa17bcc68a38d6528d4fa5425f77..785833432749f2f71f772a841699197e5d56da41 100644 (file)
@@ -2,6 +2,8 @@
  * This file is part of the libsigrok project.
  *
  * Copyright (C) 2013 Marcus Comstedt <marcus@mc.pp.se>
+ * Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
+ * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
 
 #include "protocol.h"
 
-SR_PRIV int saleae_logic16_receive_data(int fd, int revents, void *cb_data)
+#include <stdint.h>
+#include <string.h>
+#include <glib.h>
+#include <glib/gstdio.h>
+#include <stdio.h>
+#include <errno.h>
+#include <math.h>
+#include "libsigrok.h"
+#include "libsigrok-internal.h"
+
+#define FPGA_FIRMWARE_18       FIRMWARE_DIR"/saleae-logic16-fpga-18.bitstream"
+#define FPGA_FIRMWARE_33       FIRMWARE_DIR"/saleae-logic16-fpga-33.bitstream"
+
+#define MAX_SAMPLE_RATE                SR_MHZ(100)
+#define MAX_4CH_SAMPLE_RATE    SR_MHZ(50)
+#define MAX_7CH_SAMPLE_RATE    SR_MHZ(40)
+#define MAX_8CH_SAMPLE_RATE    SR_MHZ(32)
+#define MAX_10CH_SAMPLE_RATE   SR_MHZ(25)
+#define MAX_13CH_SAMPLE_RATE   SR_MHZ(16)
+
+#define BASE_CLOCK_0_FREQ      SR_MHZ(100)
+#define BASE_CLOCK_1_FREQ      SR_MHZ(160)
+
+#define COMMAND_START_ACQUISITION      1
+#define COMMAND_ABORT_ACQUISITION_ASYNC        2
+#define COMMAND_WRITE_EEPROM           6
+#define COMMAND_READ_EEPROM            7
+#define COMMAND_WRITE_LED_TABLE                0x7a
+#define COMMAND_SET_LED_MODE           0x7b
+#define COMMAND_RETURN_TO_BOOTLOADER   0x7c
+#define COMMAND_ABORT_ACQUISITION_SYNC 0x7d
+#define COMMAND_FPGA_UPLOAD_INIT       0x7e
+#define COMMAND_FPGA_UPLOAD_SEND_DATA  0x7f
+#define COMMAND_FPGA_WRITE_REGISTER    0x80
+#define COMMAND_FPGA_READ_REGISTER     0x81
+#define COMMAND_GET_REVID              0x82
+
+#define WRITE_EEPROM_COOKIE1           0x42
+#define WRITE_EEPROM_COOKIE2           0x55
+#define READ_EEPROM_COOKIE1            0x33
+#define READ_EEPROM_COOKIE2            0x81
+#define ABORT_ACQUISITION_SYNC_PATTERN 0x55
+
+#define MAX_EMPTY_TRANSFERS            64
+
+static void encrypt(uint8_t *dest, const uint8_t *src, uint8_t cnt)
+{
+       uint8_t state1 = 0x9b, state2 = 0x54;
+       uint8_t t, v;
+       int i;
+
+       for (i = 0; i < cnt; i++) {
+               v = src[i];
+               t = (((v ^ state2 ^ 0x2b) - 0x05) ^ 0x35) - 0x39;
+               t = (((t ^ state1 ^ 0x5a) - 0xb0) ^ 0x38) - 0x45;
+               dest[i] = state2 = t;
+               state1 = v;
+       }
+}
+
+static void decrypt(uint8_t *dest, const uint8_t *src, uint8_t cnt)
+{
+       uint8_t state1 = 0x9b, state2 = 0x54;
+       uint8_t t, v;
+       int i;
+
+       for (i = 0; i < cnt; i++) {
+               v = src[i];
+               t = (((v + 0x45) ^ 0x38) + 0xb0) ^ 0x5a ^ state1;
+               t = (((t + 0x39) ^ 0x35) + 0x05) ^ 0x2b ^ state2;
+               dest[i] = state1 = t;
+               state2 = v;
+       }
+}
+
+static int do_ep1_command(const struct sr_dev_inst *sdi,
+                         const uint8_t *command, uint8_t cmd_len,
+                         uint8_t *reply, uint8_t reply_len)
+{
+       uint8_t buf[64];
+       struct sr_usb_dev_inst *usb;
+       int ret, xfer;
+
+       usb = sdi->conn;
+
+       if (cmd_len < 1 || cmd_len > 64 || reply_len > 64 ||
+           command == NULL || (reply_len > 0 && reply == NULL))
+               return SR_ERR_ARG;
+
+       encrypt(buf, command, cmd_len);
+
+       ret = libusb_bulk_transfer(usb->devhdl, 1, buf, cmd_len, &xfer, 1000);
+       if (ret != 0) {
+               sr_dbg("Failed to send EP1 command 0x%02x: %s.",
+                      command[0], libusb_error_name(ret));
+               return SR_ERR;
+       }
+       if (xfer != cmd_len) {
+               sr_dbg("Failed to send EP1 command 0x%02x: incorrect length "
+                      "%d != %d.", xfer, cmd_len);
+               return SR_ERR;
+       }
+
+       if (reply_len == 0)
+               return SR_OK;
+
+       ret = libusb_bulk_transfer(usb->devhdl, 0x80 | 1, buf, reply_len,
+                                  &xfer, 1000);
+       if (ret != 0) {
+               sr_dbg("Failed to receive reply to EP1 command 0x%02x: %s.",
+                      command[0], libusb_error_name(ret));
+               return SR_ERR;
+       }
+       if (xfer != reply_len) {
+               sr_dbg("Failed to receive reply to EP1 command 0x%02x: "
+                      "incorrect length %d != %d.", xfer, reply_len);
+               return SR_ERR;
+       }
+
+       decrypt(reply, buf, reply_len);
+
+       return SR_OK;
+}
+
+static int read_eeprom(const struct sr_dev_inst *sdi,
+                      uint8_t address, uint8_t length, uint8_t *buf)
+{
+       uint8_t command[5] = {
+               COMMAND_READ_EEPROM,
+               READ_EEPROM_COOKIE1,
+               READ_EEPROM_COOKIE2,
+               address,
+               length,
+       };
+
+       return do_ep1_command(sdi, command, 5, buf, length);
+}
+
+static int upload_led_table(const struct sr_dev_inst *sdi,
+                           const uint8_t *table, uint8_t offset, uint8_t cnt)
+{
+       uint8_t chunk, command[64];
+       int ret;
+
+       if (cnt < 1 || cnt + offset > 64 || table == NULL)
+               return SR_ERR_ARG;
+
+       while (cnt > 0) {
+               chunk = (cnt > 32 ? 32 : cnt);
+
+               command[0] = COMMAND_WRITE_LED_TABLE;
+               command[1] = offset;
+               command[2] = chunk;
+               memcpy(command + 3, table, chunk);
+
+               ret = do_ep1_command(sdi, command, 3 + chunk, NULL, 0);
+               if (ret != SR_OK)
+                       return ret;
+
+               table += chunk;
+               offset += chunk;
+               cnt -= chunk;
+       }
+
+       return SR_OK;
+}
+
+static int set_led_mode(const struct sr_dev_inst *sdi,
+                       uint8_t animate, uint16_t t2reload, uint8_t div,
+                       uint8_t repeat)
+{
+       uint8_t command[6] = {
+               COMMAND_SET_LED_MODE,
+               animate,
+               t2reload & 0xff,
+               t2reload >> 8,
+               div,
+               repeat,
+       };
+
+       return do_ep1_command(sdi, command, 6, NULL, 0);
+}
+
+static int read_fpga_register(const struct sr_dev_inst *sdi,
+                             uint8_t address, uint8_t *value)
+{
+       uint8_t command[3] = {
+               COMMAND_FPGA_READ_REGISTER,
+               1,
+               address,
+       };
+
+       return do_ep1_command(sdi, command, 3, value, 1);
+}
+
+static int write_fpga_registers(const struct sr_dev_inst *sdi,
+                               uint8_t (*regs)[2], uint8_t cnt)
+{
+       uint8_t command[64];
+       int i;
+
+       if (cnt < 1 || cnt > 31)
+               return SR_ERR_ARG;
+
+       command[0] = COMMAND_FPGA_WRITE_REGISTER;
+       command[1] = cnt;
+       for (i = 0; i < cnt; i++) {
+               command[2 + 2 * i] = regs[i][0];
+               command[3 + 2 * i] = regs[i][1];
+       }
+
+       return do_ep1_command(sdi, command, 2 * (cnt + 1), NULL, 0);
+}
+
+static int write_fpga_register(const struct sr_dev_inst *sdi,
+                              uint8_t address, uint8_t value)
+{
+       uint8_t regs[2] = { address, value };
+
+       return write_fpga_registers(sdi, &regs, 1);
+}
+
+static uint8_t map_eeprom_data(uint8_t v)
+{
+       return (((v ^ 0x80) + 0x44) ^ 0xd5) + 0x69;
+}
+
+static int prime_fpga(const struct sr_dev_inst *sdi)
+{
+       uint8_t eeprom_data[16];
+       uint8_t old_reg_10, version;
+       uint8_t regs[8][2] = {
+               {10, 0x00},
+               {10, 0x40},
+               {12, 0},
+               {10, 0xc0},
+               {10, 0x40},
+               {6, 0},
+               {7, 1},
+               {7, 0}
+       };
+       int i, ret;
+
+       if ((ret = read_eeprom(sdi, 16, 16, eeprom_data)) != SR_OK)
+               return ret;
+
+       if ((ret = read_fpga_register(sdi, 10, &old_reg_10)) != SR_OK)
+               return ret;
+
+       regs[0][1] = (old_reg_10 &= 0x7f);
+       regs[1][1] |= old_reg_10;
+       regs[3][1] |= old_reg_10;
+       regs[4][1] |= old_reg_10;
+
+       for (i = 0; i < 16; i++) {
+               regs[2][1] = eeprom_data[i];
+               regs[5][1] = map_eeprom_data(eeprom_data[i]);
+               if (i)
+                       ret = write_fpga_registers(sdi, &regs[2], 6);
+               else
+                       ret = write_fpga_registers(sdi, &regs[0], 8);
+               if (ret != SR_OK)
+                       return ret;
+       }
+
+       if ((ret = write_fpga_register(sdi, 10, old_reg_10)) != SR_OK)
+               return ret;
+
+       if ((ret = read_fpga_register(sdi, 0, &version)) != SR_OK)
+               return ret;
+
+       if (version != 0x10) {
+               sr_err("Invalid FPGA bitstream version: 0x%02x != 0x10.", version);
+               return SR_ERR;
+       }
+
+       return SR_OK;
+}
+
+static void make_heartbeat(uint8_t *table, int len)
+{
+       int i, j;
+
+       memset(table, 0, len);
+       len >>= 3;
+       for (i = 0; i < 2; i++)
+               for (j = 0; j < len; j++)
+                       *table++ = sin(j * M_PI / len) * 255;
+}
+
+static int configure_led(const struct sr_dev_inst *sdi)
+{
+       uint8_t table[64];
+       int ret;
+
+       make_heartbeat(table, 64);
+       if ((ret = upload_led_table(sdi, table, 0, 64)) != SR_OK)
+               return ret;
+
+       return set_led_mode(sdi, 1, 6250, 0, 1);
+}
+
+static int upload_fpga_bitstream(const struct sr_dev_inst *sdi,
+                                enum voltage_range vrange)
+{
+       struct dev_context *devc;
+       int offset, chunksize, ret;
+       const char *filename;
+       uint8_t len, buf[256 * 62], command[64];
+       FILE *fw;
+
+       devc = sdi->priv;
+
+       if (devc->cur_voltage_range == vrange)
+               return SR_OK;
+
+       switch (vrange) {
+       case VOLTAGE_RANGE_18_33_V:
+               filename = FPGA_FIRMWARE_18;
+               break;
+       case VOLTAGE_RANGE_5_V:
+               filename = FPGA_FIRMWARE_33;
+               break;
+       default:
+               sr_err("Unsupported voltage range.");
+               return SR_ERR;
+       }
+
+       sr_info("Uploading FPGA bitstream at %s.", filename);
+       if ((fw = g_fopen(filename, "rb")) == NULL) {
+               sr_err("Unable to open bitstream file %s for reading: %s.",
+                      filename, strerror(errno));
+               return SR_ERR;
+       }
+
+       buf[0] = COMMAND_FPGA_UPLOAD_INIT;
+       if ((ret = do_ep1_command(sdi, buf, 1, NULL, 0)) != SR_OK) {
+               fclose(fw);
+               return ret;
+       }
+
+       while (1) {
+               chunksize = fread(buf, 1, sizeof(buf), fw);
+               if (chunksize == 0)
+                       break;
+
+               for (offset = 0; offset < chunksize; offset += 62) {
+                       len = (offset + 62 > chunksize ?
+                               chunksize - offset : 62);
+                       command[0] = COMMAND_FPGA_UPLOAD_SEND_DATA;
+                       command[1] = len;
+                       memcpy(command + 2, buf + offset, len);
+                       ret = do_ep1_command(sdi, command, len + 2, NULL, 0);
+                       if (ret != SR_OK) {
+                               fclose(fw);
+                               return ret;
+                       }
+               }
+
+               sr_info("Uploaded %d bytes.", chunksize);
+       }
+       fclose(fw);
+       sr_info("FPGA bitstream upload done.");
+
+       if ((ret = prime_fpga(sdi)) != SR_OK)
+               return ret;
+
+       if ((ret = configure_led(sdi)) != SR_OK)
+               return ret;
+
+       devc->cur_voltage_range = vrange;
+       return SR_OK;
+}
+
+static int abort_acquisition_sync(const struct sr_dev_inst *sdi)
 {
-       (void)fd;
+       static const uint8_t command[2] = {
+               COMMAND_ABORT_ACQUISITION_SYNC,
+               ABORT_ACQUISITION_SYNC_PATTERN,
+       };
+       uint8_t reply, expected_reply;
+       int ret;
 
-       const struct sr_dev_inst *sdi;
+       if ((ret = do_ep1_command(sdi, command, 2, &reply, 1)) != SR_OK)
+               return ret;
+
+       expected_reply = ~command[1];
+       if (reply != expected_reply) {
+               sr_err("Invalid response for abort acquisition command: "
+                      "0x%02x != 0x%02x.", reply, expected_reply);
+               return SR_ERR;
+       }
+
+       return SR_OK;
+}
+
+SR_PRIV int logic16_setup_acquisition(const struct sr_dev_inst *sdi,
+                            uint64_t samplerate, uint16_t channels)
+{
+       uint8_t clock_select, reg1, reg10;
+       uint64_t div;
+       int i, ret, nchan = 0;
        struct dev_context *devc;
 
-       if (!(sdi = cb_data))
-               return TRUE;
+       devc = sdi->priv;
+
+       if (samplerate == 0 || samplerate > MAX_SAMPLE_RATE) {
+               sr_err("Unable to sample at %" PRIu64 "Hz.", samplerate);
+               return SR_ERR;
+       }
+
+       if (BASE_CLOCK_0_FREQ % samplerate == 0 &&
+           (div = BASE_CLOCK_0_FREQ / samplerate) <= 256) {
+               clock_select = 0;
+       } else if (BASE_CLOCK_1_FREQ % samplerate == 0 &&
+                  (div = BASE_CLOCK_1_FREQ / samplerate) <= 256) {
+               clock_select = 1;
+       } else {
+               sr_err("Unable to sample at %" PRIu64 "Hz.", samplerate);
+               return SR_ERR;
+       }
+
+       for (i = 0; i < 16; i++)
+               if (channels & (1U << i))
+                       nchan++;
+
+       if ((nchan >= 13 && samplerate > MAX_13CH_SAMPLE_RATE) ||
+           (nchan >= 10 && samplerate > MAX_10CH_SAMPLE_RATE) ||
+           (nchan >= 8  && samplerate > MAX_8CH_SAMPLE_RATE) ||
+           (nchan >= 7  && samplerate > MAX_7CH_SAMPLE_RATE) ||
+           (nchan >= 4  && samplerate > MAX_4CH_SAMPLE_RATE)) {
+               sr_err("Unable to sample at %" PRIu64 "Hz "
+                      "with this many channels.", samplerate);
+               return SR_ERR;
+       }
+
+       ret = upload_fpga_bitstream(sdi, devc->selected_voltage_range);
+       if (ret != SR_OK)
+               return ret;
+
+       if ((ret = read_fpga_register(sdi, 1, &reg1)) != SR_OK)
+               return ret;
+
+       if (reg1 != 0x08) {
+               sr_dbg("Invalid state at acquisition setup: 0x%02x != 0x08.", reg1);
+               return SR_ERR;
+       }
+
+       if ((ret = write_fpga_register(sdi, 1, 0x40)) != SR_OK)
+               return ret;
+
+       if ((ret = write_fpga_register(sdi, 10, clock_select)) != SR_OK)
+               return ret;
+
+       if ((ret = write_fpga_register(sdi, 4, (uint8_t)(div - 1))) != SR_OK)
+               return ret;
+
+       if ((ret = write_fpga_register(sdi, 2, (uint8_t)(channels & 0xff))) != SR_OK)
+               return ret;
+
+       if ((ret = write_fpga_register(sdi, 3, (uint8_t)(channels >> 8))) != SR_OK)
+               return ret;
+
+       if ((ret = write_fpga_register(sdi, 1, 0x42)) != SR_OK)
+               return ret;
+
+       if ((ret = write_fpga_register(sdi, 1, 0x40)) != SR_OK)
+               return ret;
+
+       if ((ret = read_fpga_register(sdi, 1, &reg1)) != SR_OK)
+               return ret;
+
+       if (reg1 != 0x48) {
+               sr_dbg("Invalid state at acquisition setup: 0x%02x != 0x48.", reg1);
+               return SR_ERR;
+       }
+
+       if ((ret = read_fpga_register(sdi, 10, &reg10)) != SR_OK)
+               return ret;
+
+       if (reg10 != clock_select) {
+               sr_dbg("Invalid state at acquisition setup: 0x%02x != 0x%02x.",
+                      reg10, clock_select);
+               return SR_ERR;
+       }
+
+       return SR_OK;
+}
+
+SR_PRIV int logic16_start_acquisition(const struct sr_dev_inst *sdi)
+{
+       static const uint8_t command[1] = {
+               COMMAND_START_ACQUISITION,
+       };
+       int ret;
+
+       if ((ret = do_ep1_command(sdi, command, 1, NULL, 0)) != SR_OK)
+               return ret;
+
+       return write_fpga_register(sdi, 1, 0x41);
+}
+
+SR_PRIV int logic16_abort_acquisition(const struct sr_dev_inst *sdi)
+{
+       static const uint8_t command[1] = {
+               COMMAND_ABORT_ACQUISITION_ASYNC,
+       };
+       int ret;
+       uint8_t reg1, reg8, reg9;
+
+       if ((ret = do_ep1_command(sdi, command, 1, NULL, 0)) != SR_OK)
+               return ret;
+
+       if ((ret = write_fpga_register(sdi, 1, 0x00)) != SR_OK)
+               return ret;
+
+       if ((ret = read_fpga_register(sdi, 1, &reg1)) != SR_OK)
+               return ret;
+
+       if (reg1 != 0x08) {
+               sr_dbg("Invalid state at acquisition stop: 0x%02x != 0x08.", reg1);
+               return SR_ERR;
+       }
+
+       if ((ret = read_fpga_register(sdi, 8, &reg8)) != SR_OK)
+               return ret;
+
+       if ((ret = read_fpga_register(sdi, 9, &reg9)) != SR_OK)
+               return ret;
+
+       return SR_OK;
+}
+
+SR_PRIV int logic16_init_device(const struct sr_dev_inst *sdi)
+{
+       struct dev_context *devc;
+       int ret;
+
+       devc = sdi->priv;
+
+       devc->cur_voltage_range = VOLTAGE_RANGE_UNKNOWN;
+
+       if ((ret = abort_acquisition_sync(sdi)) != SR_OK)
+               return ret;
+
+       if ((ret = read_eeprom(sdi, 8, 8, devc->eeprom_data)) != SR_OK)
+               return ret;
+
+       ret = upload_fpga_bitstream(sdi, devc->selected_voltage_range);
+       if (ret != SR_OK)
+               return ret;
+
+       return SR_OK;
+}
+
+static void finish_acquisition(struct sr_dev_inst *sdi)
+{
+       struct sr_datafeed_packet packet;
+       struct dev_context *devc;
+
+       devc = sdi->priv;
+
+       /* Terminate session. */
+       packet.type = SR_DF_END;
+       sr_session_send(devc->cb_data, &packet);
+
+       /* Remove fds from polling. */
+       usb_source_remove(sdi->session, devc->ctx);
+
+       devc->num_transfers = 0;
+       g_free(devc->transfers);
+       g_free(devc->convbuffer);
+       if (devc->stl) {
+               soft_trigger_logic_free(devc->stl);
+               devc->stl = NULL;
+       }
+}
+
+static void free_transfer(struct libusb_transfer *transfer)
+{
+       struct sr_dev_inst *sdi;
+       struct dev_context *devc;
+       unsigned int i;
+
+       sdi = transfer->user_data;
+       devc = sdi->priv;
+
+       g_free(transfer->buffer);
+       transfer->buffer = NULL;
+       libusb_free_transfer(transfer);
+
+       for (i = 0; i < devc->num_transfers; i++) {
+               if (devc->transfers[i] == transfer) {
+                       devc->transfers[i] = NULL;
+                       break;
+               }
+       }
+
+       devc->submitted_transfers--;
+       if (devc->submitted_transfers == 0)
+               finish_acquisition(sdi);
+}
+
+static void resubmit_transfer(struct libusb_transfer *transfer)
+{
+       int ret;
+
+       if ((ret = libusb_submit_transfer(transfer)) == LIBUSB_SUCCESS)
+               return;
+
+       free_transfer(transfer);
+       /* TODO: Stop session? */
+
+       sr_err("%s: %s", __func__, libusb_error_name(ret));
+}
+
+static size_t convert_sample_data(struct dev_context *devc,
+               uint8_t *dest, size_t destcnt, const uint8_t *src, size_t srccnt)
+{
+       uint16_t *channel_data;
+       int i, cur_channel;
+       size_t ret = 0;
+       uint16_t sample, channel_mask;
+
+       srccnt /= 2;
+
+       channel_data = devc->channel_data;
+       cur_channel = devc->cur_channel;
+
+       while (srccnt--) {
+               sample = src[0] | (src[1] << 8);
+               src += 2;
+
+               channel_mask = devc->channel_masks[cur_channel];
+
+               for (i = 15; i >= 0; --i, sample >>= 1)
+                       if (sample & 1)
+                               channel_data[i] |= channel_mask;
+
+               if (++cur_channel == devc->num_channels) {
+                       cur_channel = 0;
+                       if (destcnt < 16 * 2) {
+                               sr_err("Conversion buffer too small!");
+                               break;
+                       }
+                       memcpy(dest, channel_data, 16 * 2);
+                       memset(channel_data, 0, 16 * 2);
+                       dest += 16 * 2;
+                       ret += 16;
+                       destcnt -= 16 * 2;
+               }
+       }
+
+       devc->cur_channel = cur_channel;
+
+       return ret;
+}
+
+SR_PRIV void logic16_receive_transfer(struct libusb_transfer *transfer)
+{
+       gboolean packet_has_error = FALSE;
+       struct sr_datafeed_packet packet;
+       struct sr_datafeed_logic logic;
+       struct sr_dev_inst *sdi;
+       struct dev_context *devc;
+       size_t new_samples, num_samples;
+       int trigger_offset;
+
+       sdi = transfer->user_data;
+       devc = sdi->priv;
+
+       /*
+        * If acquisition has already ended, just free any queued up
+        * transfer that come in.
+        */
+       if (devc->sent_samples < 0) {
+               free_transfer(transfer);
+               return;
+       }
+
+       sr_info("receive_transfer(): status %d received %d bytes.",
+               transfer->status, transfer->actual_length);
+
+       switch (transfer->status) {
+       case LIBUSB_TRANSFER_NO_DEVICE:
+               devc->sent_samples = -2;
+               free_transfer(transfer);
+               return;
+       case LIBUSB_TRANSFER_COMPLETED:
+       case LIBUSB_TRANSFER_TIMED_OUT: /* We may have received some data though. */
+               break;
+       default:
+               packet_has_error = TRUE;
+               break;
+       }
+
+       if (transfer->actual_length & 1) {
+               sr_err("Got an odd number of bytes from the device. "
+                      "This should not happen.");
+               /* Bail out right away. */
+               packet_has_error = TRUE;
+               devc->empty_transfer_count = MAX_EMPTY_TRANSFERS;
+       }
+
+       if (transfer->actual_length == 0 || packet_has_error) {
+               devc->empty_transfer_count++;
+               if (devc->empty_transfer_count > MAX_EMPTY_TRANSFERS) {
+                       /*
+                        * The FX2 gave up. End the acquisition, the frontend
+                        * will work out that the samplecount is short.
+                        */
+                       devc->sent_samples = -2;
+                       free_transfer(transfer);
+               } else {
+                       resubmit_transfer(transfer);
+               }
+               return;
+       } else {
+               devc->empty_transfer_count = 0;
+       }
+
+       new_samples = convert_sample_data(devc, devc->convbuffer,
+                       devc->convbuffer_size, transfer->buffer, transfer->actual_length);
+
+       if (new_samples > 0) {
+               if (devc->trigger_fired) {
+                       /* Send the incoming transfer to the session bus. */
+                       packet.type = SR_DF_LOGIC;
+                       packet.payload = &logic;
+                       if (devc->limit_samples &&
+                                       new_samples > devc->limit_samples - devc->sent_samples)
+                               new_samples = devc->limit_samples - devc->sent_samples;
+                       logic.length = new_samples * 2;
+                       logic.unitsize = 2;
+                       logic.data = devc->convbuffer;
+                       sr_session_send(devc->cb_data, &packet);
+                       devc->sent_samples += new_samples;
+               } else {
+                       trigger_offset = soft_trigger_logic_check(devc->stl,
+                                       devc->convbuffer, new_samples * 2);
+                       if (trigger_offset > -1) {
+                               packet.type = SR_DF_LOGIC;
+                               packet.payload = &logic;
+                               num_samples = new_samples - trigger_offset;
+                               if (devc->limit_samples &&
+                                               num_samples > devc->limit_samples - devc->sent_samples)
+                                       num_samples = devc->limit_samples - devc->sent_samples;
+                               logic.length = num_samples * 2;
+                               logic.unitsize = 2;
+                               logic.data = devc->convbuffer + trigger_offset * 2;
+                               sr_session_send(devc->cb_data, &packet);
+                               devc->sent_samples += num_samples;
 
-       if (!(devc = sdi->priv))
-               return TRUE;
+                               devc->trigger_fired = TRUE;
+                       }
+               }
 
-       if (revents == G_IO_IN) {
-               /* TODO */
+               if (devc->limit_samples &&
+                               (uint64_t)devc->sent_samples >= devc->limit_samples) {
+                       devc->sent_samples = -2;
+                       free_transfer(transfer);
+                       return;
+               }
        }
 
-       return TRUE;
+       resubmit_transfer(transfer);
 }