From: Daniel Elstner <redacted>
Date: Mon, 13 Jan 2014 21:57:59 +0000 (+0100)
Subject: sysclk-lwla: Implement support for the LWLA1034.
X-Git-Tag: libsigrok-0.3.0~294
X-Git-Url: https://sigrok.org/gitweb/?p=libsigrok.git;a=commitdiff_plain;h=5874e88d83cabbec62e36c37e9016fab983d957b;hp=aeaad0b0b5db53f3d600359834b2738422feaeaf

sysclk-lwla: Implement support for the LWLA1034.
---

diff --git a/contrib/z60_libsigrok.rules b/contrib/z60_libsigrok.rules
index 16e71cd7..6ec5667f 100644
--- a/contrib/z60_libsigrok.rules
+++ b/contrib/z60_libsigrok.rules
@@ -142,6 +142,9 @@ ATTRS{idVendor}=="0925", ATTRS{idProduct}=="3881", MODE="664", GROUP="plugdev"
 # Saleae Logic16
 ATTRS{idVendor}=="21a9", ATTRS{idProduct}=="1001", MODE="664", GROUP="plugdev"
 
+# SysClk LWLA1034
+ATTRS{idVendor}=="2961", ATTRS{idProduct}=="6689", MODE="664", GROUP="plugdev"
+
 # UNI-T UT-D04 multimeter cable (for various UNI-T and rebranded DMMs)
 # http://sigrok.org/wiki/Device_cables#UNI-T_UT-D04
 # UNI-T UT325
diff --git a/hardware/sysclk-lwla/Makefile.am b/hardware/sysclk-lwla/Makefile.am
index 31bbcbd0..3733f750 100644
--- a/hardware/sysclk-lwla/Makefile.am
+++ b/hardware/sysclk-lwla/Makefile.am
@@ -19,11 +19,15 @@
 
 if HW_SYSCLK_LWLA
 
+AM_CPPFLAGS = -DFIRMWARE_DIR='"$(FIRMWARE_DIR)"'
+
 # Local lib, this is NOT meant to be installed!
 noinst_LTLIBRARIES = libsigrok_hw_sysclk_lwla.la
 
 libsigrok_hw_sysclk_lwla_la_SOURCES = \
 	api.c \
+	lwla.c \
+	lwla.h \
 	protocol.c \
 	protocol.h
 
diff --git a/hardware/sysclk-lwla/api.c b/hardware/sysclk-lwla/api.c
index 26556eb5..444b6a1b 100644
--- a/hardware/sysclk-lwla/api.c
+++ b/hardware/sysclk-lwla/api.c
@@ -18,59 +18,208 @@
  */
 
 #include "protocol.h"
+#include "libsigrok.h"
+#include "libsigrok-internal.h"
+#include <glib.h>
+#include <libusb.h>
+#include <stdlib.h>
+#include <string.h>
+
+static const int32_t hwcaps[] = {
+	SR_CONF_LOGIC_ANALYZER,
+	SR_CONF_SAMPLERATE,
+	SR_CONF_EXTERNAL_CLOCK,
+	SR_CONF_TRIGGER_TYPE,
+	SR_CONF_LIMIT_SAMPLES,
+};
+
+/* The hardware supports more samplerates than these, but these are the
+ * options hardcoded into the vendor's Windows GUI.
+ */
+static const uint64_t samplerates[] = {
+	SR_MHZ(125), SR_MHZ(100),
+	SR_MHZ(50),  SR_MHZ(20),  SR_MHZ(10),
+	SR_MHZ(5),   SR_MHZ(2),   SR_MHZ(1),
+	SR_KHZ(500), SR_KHZ(200), SR_KHZ(100),
+	SR_KHZ(50),  SR_KHZ(20),  SR_KHZ(10),
+	SR_KHZ(5),   SR_KHZ(2),   SR_KHZ(1),
+	SR_HZ(500),  SR_HZ(200),  SR_HZ(100),
+};
 
 SR_PRIV struct sr_dev_driver sysclk_lwla_driver_info;
-static struct sr_dev_driver *di = &sysclk_lwla_driver_info;
+static struct sr_dev_driver *const di = &sysclk_lwla_driver_info;
 
 static int init(struct sr_context *sr_ctx)
 {
 	return std_init(sr_ctx, di, LOG_PREFIX);
 }
 
+static GSList *gen_probe_list(int num_probes)
+{
+	GSList *list;
+	struct sr_probe *probe;
+	int i;
+	char name[8];
+
+	list = NULL;
+
+	for (i = num_probes; i > 0; --i) {
+		/* The LWLA series simply number probes from CH1 to CHxx. */
+		g_ascii_formatd(name, sizeof name, "CH%.0f", i);
+
+		probe = sr_probe_new(i - 1, SR_PROBE_LOGIC, TRUE, name);
+		list = g_slist_prepend(list, probe);
+	}
+
+	return list;
+}
+
 static GSList *scan(GSList *options)
 {
+	GSList *usb_devices, *devices, *node;
 	struct drv_context *drvc;
-	GSList *devices;
+	struct sr_dev_inst *sdi;
+	struct dev_context *devc;
+	struct sr_usb_dev_inst *usb;
+	int device_index;
 
 	(void)options;
 
 	devices = NULL;
 	drvc = di->priv;
 	drvc->instances = NULL;
+	device_index = 0;
+
+	usb_devices = sr_usb_find(drvc->sr_ctx->libusb_ctx, USB_VID_PID);
+
+	for (node = usb_devices; node != NULL; node = node->next) {
+		usb = node->data;
+
+		/* Allocate memory for our private driver context. */
+		devc = g_try_new0(struct dev_context, 1);
+		if (!devc) {
+			sr_err("Device context malloc failed.");
+			sr_usb_dev_inst_free(usb);
+			continue;
+		}
+		/* Register the device with libsigrok. */
+		sdi = sr_dev_inst_new(device_index, SR_ST_INACTIVE,
+				      VENDOR_NAME, MODEL_NAME, NULL);
+		if (!sdi) {
+			sr_err("Failed to instantiate device.");
+			g_free(devc);
+			sr_usb_dev_inst_free(usb);
+			continue;
+		}
+		sdi->driver = di;
+		sdi->priv = devc;
+		sdi->inst_type = SR_INST_USB;
+		sdi->conn = usb;
+		sdi->probes = gen_probe_list(NUM_PROBES);
+
+		drvc->instances = g_slist_append(drvc->instances, sdi);
+		devices = g_slist_append(devices, sdi);
+	}
 
-	/* TODO: scan for devices, either based on a SR_CONF_CONN option
-	 * or on a USB scan. */
+	g_slist_free(usb_devices);
 
 	return devices;
 }
 
 static GSList *dev_list(void)
 {
-	return ((struct drv_context *)(di->priv))->instances;
+	struct drv_context *drvc;
+
+	drvc = di->priv;
+
+	return drvc->instances;
+}
+
+static void clear_dev_context(void *priv)
+{
+	struct dev_context *devc;
+
+	devc = priv;
+
+	sr_dbg("Device context cleared.");
+
+	lwla_free_acquisition_state(devc->acquisition);
+	g_free(devc);
 }
 
 static int dev_clear(void)
 {
-	return std_dev_clear(di, NULL);
+	return std_dev_clear(di, &clear_dev_context);
 }
 
 static int dev_open(struct sr_dev_inst *sdi)
 {
-	(void)sdi;
+	struct drv_context *drvc;
+	struct dev_context *devc;
+	struct sr_usb_dev_inst *usb;
+	int ret;
 
-	/* TODO: get handle from sdi->conn and open it. */
+	drvc = di->priv;
 
-	sdi->status = SR_ST_ACTIVE;
+	if (!drvc) {
+		sr_err("Driver was not initialized.");
+		return SR_ERR;
+	}
 
-	return SR_OK;
+	usb  = sdi->conn;
+	devc = sdi->priv;
+
+	ret = sr_usb_open(drvc->sr_ctx->libusb_ctx, usb);
+	if (ret != SR_OK)
+		return ret;
+
+	ret = libusb_claim_interface(usb->devhdl, USB_INTERFACE);
+	if (ret < 0) {
+		sr_err("Failed to claim interface: %s.",
+			libusb_error_name(ret));
+		return SR_ERR;
+	}
+
+	sdi->status = SR_ST_INITIALIZING;
+
+	if (devc->samplerate == 0)
+		/* Apply default if the samplerate hasn't been set yet. */
+		devc->samplerate = DEFAULT_SAMPLERATE;
+
+	ret = lwla_init_device(sdi);
+
+	if (ret == SR_OK)
+		sdi->status = SR_ST_ACTIVE;
+
+	return ret;
 }
 
 static int dev_close(struct sr_dev_inst *sdi)
 {
-	(void)sdi;
+	struct sr_usb_dev_inst *usb;
+	struct dev_context *devc;
+
+	if (!di->priv) {
+		sr_err("Driver was not initialized.");
+		return SR_ERR;
+	}
+
+	usb  = sdi->conn;
+	devc = sdi->priv;
 
-	/* TODO: get handle from sdi->conn and close it. */
+	if (!usb->devhdl)
+		return SR_OK;
 
+	/* Trigger download of the shutdown bitstream. */
+	devc->selected_clock_source = CLOCK_SOURCE_NONE;
+
+	if (lwla_set_clock_source(sdi) != SR_OK)
+		sr_err("Unable to shut down device.");
+
+	libusb_release_interface(usb->devhdl, USB_INTERFACE);
+	libusb_close(usb->devhdl);
+
+	usb->devhdl = NULL;
 	sdi->status = SR_ST_INACTIVE;
 
 	return SR_OK;
@@ -78,83 +227,228 @@ static int dev_close(struct sr_dev_inst *sdi)
 
 static int cleanup(void)
 {
-	dev_clear();
-
-	/* TODO: free other driver resources, if any. */
-
-	return SR_OK;
+	return dev_clear();
 }
 
 static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
-		const struct sr_probe_group *probe_group)
+		      const struct sr_probe_group *probe_group)
 {
-	int ret;
+	struct dev_context *devc;
 
-	(void)sdi;
-	(void)data;
 	(void)probe_group;
 
-	ret = SR_OK;
+	if (!sdi)
+		return SR_ERR_ARG;
+
+	devc = sdi->priv;
+
 	switch (key) {
-	/* TODO */
+	case SR_CONF_SAMPLERATE:
+		*data = g_variant_new_uint64(devc->samplerate);
+		break;
+	case SR_CONF_LIMIT_SAMPLES:
+		*data = g_variant_new_uint64(devc->limit_samples);
+		break;
+	case SR_CONF_EXTERNAL_CLOCK:
+		*data = g_variant_new_boolean(devc->selected_clock_source
+						>= CLOCK_SOURCE_EXT_RISE);
+		break;
 	default:
 		return SR_ERR_NA;
 	}
 
-	return ret;
+	return SR_OK;
 }
 
 static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
-		const struct sr_probe_group *probe_group)
+		      const struct sr_probe_group *probe_group)
 {
-	int ret;
+	struct dev_context *devc;
+	uint64_t rate;
 
-	(void)data;
 	(void)probe_group;
 
-	if (sdi->status != SR_ST_ACTIVE)
+	devc = sdi->priv;
+	if (!devc)
 		return SR_ERR_DEV_CLOSED;
 
-	ret = SR_OK;
 	switch (key) {
-	/* TODO */
+	case SR_CONF_SAMPLERATE:
+		rate = g_variant_get_uint64(data);
+		sr_info("Setting samplerate %" G_GUINT64_FORMAT, rate);
+		if (rate > samplerates[0]
+		    || rate < samplerates[G_N_ELEMENTS(samplerates) - 1])
+			return SR_ERR_SAMPLERATE;
+		devc->samplerate = rate;
+		break;
+	case SR_CONF_LIMIT_SAMPLES:
+		devc->limit_samples = g_variant_get_uint64(data);
+		break;
+	case SR_CONF_EXTERNAL_CLOCK:
+		if (g_variant_get_boolean(data)) {
+			sr_info("Enabling external clock.");
+			/* TODO: Allow the external clock to be inverted */
+			devc->selected_clock_source = CLOCK_SOURCE_EXT_RISE;
+		} else {
+			sr_info("Disabling external clock.");
+			devc->selected_clock_source = CLOCK_SOURCE_INT;
+		}
+		if (sdi->status == SR_ST_ACTIVE)
+			return lwla_set_clock_source(sdi);
+		break;
 	default:
-		ret = SR_ERR_NA;
+		return SR_ERR_NA;
 	}
 
-	return ret;
+	return SR_OK;
 }
 
 static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
-		const struct sr_probe_group *probe_group)
+		       const struct sr_probe_group *probe_group)
 {
-	int ret;
+	GVariant *gvar;
+	GVariantBuilder gvb;
 
 	(void)sdi;
-	(void)data;
 	(void)probe_group;
 
-	ret = SR_OK;
 	switch (key) {
-	/* TODO */
+	case SR_CONF_DEVICE_OPTIONS:
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		break;
+	case SR_CONF_SAMPLERATE:
+		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
+		gvar = g_variant_new_fixed_array(G_VARIANT_TYPE("t"),
+				samplerates, ARRAY_SIZE(samplerates),
+				sizeof(uint64_t));
+		g_variant_builder_add(&gvb, "{sv}", "samplerates", gvar);
+		*data = g_variant_builder_end(&gvb);
+		break;
+	case SR_CONF_TRIGGER_TYPE:
+		*data = g_variant_new_string(TRIGGER_TYPES);
+		break;
 	default:
 		return SR_ERR_NA;
 	}
 
-	return ret;
+	return SR_OK;
 }
 
-static int dev_acquisition_start(const struct sr_dev_inst *sdi,
-				    void *cb_data)
+static int configure_probes(const struct sr_dev_inst *sdi)
 {
-	(void)sdi;
+	struct dev_context *devc;
+	const struct sr_probe *probe;
+	const GSList *node;
+	uint64_t probe_bit;
+
+	devc = sdi->priv;
+
+	devc->channel_mask = 0;
+	devc->trigger_mask = 0;
+	devc->trigger_edge_mask = 0;
+	devc->trigger_values = 0;
+
+	for (node = sdi->probes, probe_bit = 1;
+			node != NULL;
+			node = node->next, probe_bit <<= 1) {
+
+		if (probe_bit >= ((uint64_t)1 << NUM_PROBES)) {
+			sr_err("Channels over the limit of %d.", NUM_PROBES);
+			return SR_ERR;
+		}
+		probe = node->data;
+		if (!probe || !probe->enabled)
+			continue;
+
+		/* Enable input channel for this probe. */
+		devc->channel_mask |= probe_bit;
+
+		if (!probe->trigger || probe->trigger[0] == '\0')
+			continue;
+
+		if (probe->trigger[1] != '\0') {
+			sr_err("Only one trigger stage is supported.");
+			return SR_ERR;
+		}
+		/* Enable trigger for this probe. */
+		devc->trigger_mask |= probe_bit;
+
+		/* Configure edge mask and trigger value. */
+		switch (probe->trigger[0]) {
+		case '1': devc->trigger_values |= probe_bit;
+		case '0': break;
+
+		case 'r': devc->trigger_values |= probe_bit;
+		case 'f': devc->trigger_edge_mask |= probe_bit;
+			  break;
+		default:
+			sr_err("Trigger type '%c' is not supported.",
+			       probe->trigger[0]);
+			return SR_ERR;
+		}
+	}
+	return SR_OK;
+}
+
+static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
+{
+	struct drv_context *drvc;
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+	int ret;
+
 	(void)cb_data;
 
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	/* TODO: configure hardware, reset acquisition state, set up
-	 * callbacks and send header packet. */
+	devc = sdi->priv;
+	drvc = di->priv;
+
+	if (devc->acquisition) {
+		sr_err("Acquisition still in progress?");
+		return SR_ERR;
+	}
+	acq = lwla_alloc_acquisition_state();
+	if (!acq)
+		return SR_ERR_MALLOC;
+
+	devc->stopping_in_progress = FALSE;
+	devc->transfer_error = FALSE;
+
+	ret = configure_probes(sdi);
+	if (ret != SR_OK) {
+		sr_err("Failed to configure probes.");
+		lwla_free_acquisition_state(acq);
+		return ret;
+	}
+
+	sr_info("Starting acquisition.");
+
+	devc->acquisition = acq;
+	ret = lwla_setup_acquisition(sdi);
+	if (ret != SR_OK) {
+		sr_err("Failed to set up aquisition.");
+		devc->acquisition = NULL;
+		lwla_free_acquisition_state(acq);
+		return ret;
+	}
+
+	ret = lwla_start_acquisition(sdi);
+	if (ret != SR_OK) {
+		sr_err("Failed to start aquisition.");
+		devc->acquisition = NULL;
+		lwla_free_acquisition_state(acq);
+		return ret;
+	}
+	usb_source_add(drvc->sr_ctx, 100, &lwla_receive_data,
+		       (struct sr_dev_inst *)sdi);
+
+	sr_info("Waiting for data.");
+
+	/* Send header packet to the session bus. */
+	std_session_send_df_header(sdi, LOG_PREFIX);
 
 	return SR_OK;
 }
@@ -166,14 +460,16 @@ static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	/* TODO: stop acquisition. */
+	sr_dbg("Stopping acquisition.");
+
+	sdi->status = SR_ST_STOPPING;
 
 	return SR_OK;
 }
 
 SR_PRIV struct sr_dev_driver sysclk_lwla_driver_info = {
 	.name = "sysclk-lwla",
-	.longname = "SysClk LWLA",
+	.longname = "SysClk LWLA series",
 	.api_version = 1,
 	.init = init,
 	.cleanup = cleanup,
diff --git a/hardware/sysclk-lwla/lwla.c b/hardware/sysclk-lwla/lwla.c
new file mode 100644
index 00000000..82dc90d4
--- /dev/null
+++ b/hardware/sysclk-lwla/lwla.c
@@ -0,0 +1,186 @@
+/*
+ * This file is part of the libsigrok project.
+ *
+ * Copyright (C) 2014 Daniel Elstner <daniel.kitta@gmail.com>
+ *
+ * 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
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "lwla.h"
+#include "protocol.h"
+#include "libsigrok-internal.h"
+
+SR_PRIV int lwla_send_bitstream(const struct sr_usb_dev_inst *usb,
+				const char *filename)
+{
+	GMappedFile *file;
+	GError *error;
+	char *stream;
+	size_t length;
+	int ret;
+	int xfer_len;
+
+	if (usb == NULL || filename == NULL)
+		return SR_ERR_ARG;
+
+	sr_info("Downloading FPGA bitstream at '%s'.", filename);
+
+	/* Map bitstream file into memory. */
+	error = NULL;
+	file = g_mapped_file_new(filename, FALSE, &error);
+	if (!file) {
+		sr_err("Unable to open bitstream file: %s.", error->message);
+		g_error_free(error);
+		return SR_ERR;
+	}
+	stream = g_mapped_file_get_contents(file);
+	length = g_mapped_file_get_length(file);
+
+	/* Sanity check. */
+	if (!stream || length < 4 || RB32(stream) != length) {
+		sr_err("Invalid FPGA bitstream.");
+		g_mapped_file_unref(file);
+		return SR_ERR;
+	}
+
+	/* Transfer the entire bitstream in one URB. */
+	ret = libusb_bulk_transfer(usb->devhdl, EP_BITSTREAM,
+				   (unsigned char *)stream, length,
+				   &xfer_len, USB_TIMEOUT);
+	if (ret != 0) {
+		sr_err("Failed to transfer bitstream: %s.",
+		       libusb_error_name(ret));
+		g_mapped_file_unref(file);
+		return SR_ERR;
+	}
+	if (xfer_len != (int)length) {
+		sr_err("Failed to transfer bitstream: incorrect length "
+		       "%d != %d.", xfer_len, (int)length);
+		g_mapped_file_unref(file);
+		return SR_ERR;
+	}
+	g_mapped_file_unref(file);
+	sr_info("FPGA bitstream download of %d bytes done.", xfer_len);
+
+	/* This delay appears to be necessary for reliable operation. */
+	g_usleep(30000);
+
+	return SR_OK;
+}
+
+SR_PRIV int lwla_send_command(const struct sr_usb_dev_inst *usb,
+			      const uint16_t *command, int cmd_len)
+{
+	int ret;
+	int xfer_len = 0;
+
+	if (usb == NULL || command == NULL || cmd_len < 1)
+		return SR_ERR_ARG;
+
+	ret = libusb_bulk_transfer(usb->devhdl, EP_COMMAND,
+				   (unsigned char *)command, cmd_len * 2,
+				   &xfer_len, USB_TIMEOUT);
+	if (ret != 0) {
+		sr_dbg("Failed to send command %u: %s.",
+		       LWLA_READ16(command), libusb_error_name(ret));
+		return SR_ERR;
+	}
+	if (xfer_len != cmd_len * 2) {
+		sr_dbg("Failed to send command %u: incorrect length %d != %d.",
+		       LWLA_READ16(command), xfer_len, cmd_len * 2);
+		return SR_ERR;
+	}
+	return SR_OK;
+}
+
+SR_PRIV int lwla_receive_reply(const struct sr_usb_dev_inst *usb,
+			       uint16_t *reply, int reply_len, int expect_len)
+{
+	int ret;
+	int xfer_len = 0;
+
+	if (reply_len == 0)
+		return SR_OK;
+
+	if (usb == NULL || reply == NULL || reply_len < 0)
+		return SR_ERR_ARG;
+
+	ret = libusb_bulk_transfer(usb->devhdl, EP_REPLY,
+				   (unsigned char *)reply, reply_len * 2,
+				   &xfer_len, USB_TIMEOUT);
+	if (ret != 0) {
+		sr_dbg("Failed to receive reply: %s.", libusb_error_name(ret));
+		return SR_ERR;
+	}
+	if (xfer_len != expect_len * 2) {
+		sr_dbg("Failed to receive reply: incorrect length %d != %d.",
+		       xfer_len, expect_len * 2);
+		return SR_ERR;
+	}
+	return SR_OK;
+}
+
+SR_PRIV int lwla_read_reg(const struct sr_usb_dev_inst *usb,
+			  uint16_t reg, uint32_t *value)
+{
+	int ret;
+	uint16_t command[2];
+	uint16_t reply[256];
+
+	command[0] = LWLA_WORD(CMD_READ_REG);
+	command[1] = LWLA_WORD(reg);
+
+	ret = lwla_send_command(usb, command, G_N_ELEMENTS(command));
+
+	if (ret != SR_OK)
+		return ret;
+
+	ret = lwla_receive_reply(usb, reply, G_N_ELEMENTS(reply), 2);
+
+	if (ret == SR_OK)
+		*value = LWLA_READ32(reply);
+
+	return ret;
+}
+
+SR_PRIV int lwla_write_reg(const struct sr_usb_dev_inst *usb,
+			   uint16_t reg, uint32_t value)
+{
+	uint16_t command[4];
+
+	command[0] = LWLA_WORD(CMD_WRITE_REG);
+	command[1] = LWLA_WORD(reg);
+	command[2] = LWLA_WORD_0(value);
+	command[3] = LWLA_WORD_1(value);
+
+	return lwla_send_command(usb, command, G_N_ELEMENTS(command));
+}
+
+SR_PRIV int lwla_write_regs(const struct sr_usb_dev_inst *usb,
+			    const struct regval_pair *regvals, int count)
+{
+	int i;
+	int ret;
+
+	ret = SR_OK;
+
+	for (i = 0; i < count; ++i) {
+		ret = lwla_write_reg(usb, regvals[i].reg, regvals[i].val);
+
+		if (ret != SR_OK)
+			break;
+	}
+
+	return ret;
+}
diff --git a/hardware/sysclk-lwla/lwla.h b/hardware/sysclk-lwla/lwla.h
new file mode 100644
index 00000000..78c1183c
--- /dev/null
+++ b/hardware/sysclk-lwla/lwla.h
@@ -0,0 +1,122 @@
+/*
+ * This file is part of the libsigrok project.
+ *
+ * Copyright (C) 2014 Daniel Elstner <daniel.kitta@gmail.com>
+ *
+ * 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
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef LIBSIGROK_HARDWARE_SYSCLK_LWLA_LWLA_H
+#define LIBSIGROK_HARDWARE_SYSCLK_LWLA_LWLA_H
+
+#include "libsigrok.h"
+#include <stdint.h>
+#include <libusb.h>
+#include <glib.h>
+
+struct sr_usb_dev_inst;
+
+/* Read mixed endian words from a buffer of 16-bit units. */
+#define LWLA_READ16(buf) GUINT16_FROM_LE(*(buf))
+#define LWLA_READ32(buf) \
+	(((uint32_t)GUINT16_FROM_LE((buf)[0]) << 16) | \
+	 ((uint32_t)GUINT16_FROM_LE((buf)[1])))
+#define LWLA_READ64(buf) \
+	(((uint64_t)LWLA_READ32((buf))) | \
+	 ((uint64_t)LWLA_READ32((buf) + 2) << 32))
+
+/* Convert 16-bit argument to little endian. */
+#define LWLA_WORD(val) GUINT16_TO_LE(val)
+
+/* Extract 16-bit units from 32/64-bit value in mixed endian order. */
+#define LWLA_WORD_0(val) GUINT16_TO_LE(((val) & 0xFFFF0000u) >> 16)
+#define LWLA_WORD_1(val) GUINT16_TO_LE(((val) & 0x0000FFFFu))
+#define LWLA_WORD_2(val) \
+	GUINT16_TO_LE(((val) & G_GUINT64_CONSTANT(0xFFFF000000000000)) >> 48)
+#define LWLA_WORD_3(val) \
+	GUINT16_TO_LE(((val) & G_GUINT64_CONSTANT(0x0000FFFF00000000)) >> 32)
+
+/** USB device end points.
+ */
+enum {
+	EP_COMMAND   = 2,
+	EP_BITSTREAM = 4,
+	EP_REPLY     = 6 | LIBUSB_ENDPOINT_IN
+};
+
+/** LWLA protocol command ID codes.
+ */
+enum {
+	CMD_READ_REG	= 1,
+	CMD_WRITE_REG	= 2,
+	CMD_READ_MEM	= 6,
+	CMD_CAP_SETUP	= 7,
+	CMD_CAP_STATUS	= 8,
+};
+
+/** LWLA capture state flags.
+ */
+enum {
+	STATUS_CAPTURING = 1 << 1,
+	STATUS_TRIGGERED = 1 << 4,
+	STATUS_MEM_AVAIL = 1 << 5,
+	STATUS_FLAG_MASK = 0x3F
+};
+
+/** LWLA register addresses.
+ */
+enum {
+	REG_MEM_CTRL2   = 0x1074, /* capture buffer control ??? */
+	REG_MEM_FILL    = 0x1078, /* capture buffer fill level */
+	REG_MEM_CTRL4   = 0x107C, /* capture buffer control ??? */
+
+	REG_DIV_BYPASS  = 0x1094, /* bypass clock divider flag */
+
+	REG_CMD_CTRL1   = 0x10B0, /* command control ??? */
+	REG_CMD_CTRL2   = 0x10B4, /* command control ??? */
+	REG_CMD_CTRL3   = 0x10B8, /* command control ??? */
+	REG_CMD_CTRL4   = 0x10BC, /* command control ??? */
+
+	REG_FREQ_CH1    = 0x10C0, /* channel 1 live frequency */
+	REG_FREQ_CH2    = 0x10C4, /* channel 2 live frequency */
+	REG_FREQ_CH3    = 0x10C8, /* channel 3 live frequency */
+	REG_FREQ_CH4    = 0x10CC, /* channel 4 live frequency */
+};
+
+/** Register/value pair.
+ */
+struct regval_pair {
+	unsigned int reg;
+	unsigned int val;
+};
+
+SR_PRIV int lwla_send_bitstream(const struct sr_usb_dev_inst *usb,
+				const char *filename);
+
+SR_PRIV int lwla_send_command(const struct sr_usb_dev_inst *usb,
+			      const uint16_t *command, int cmd_len);
+
+SR_PRIV int lwla_receive_reply(const struct sr_usb_dev_inst *usb,
+			       uint16_t *reply, int reply_len, int expect_len);
+
+SR_PRIV int lwla_read_reg(const struct sr_usb_dev_inst *usb,
+			  uint16_t reg, uint32_t *value);
+
+SR_PRIV int lwla_write_reg(const struct sr_usb_dev_inst *usb,
+			   uint16_t reg, uint32_t value);
+
+SR_PRIV int lwla_write_regs(const struct sr_usb_dev_inst *usb,
+			    const struct regval_pair *regvals, int count);
+
+#endif /* !LIBSIGROK_HARDWARE_SYSCLK_LWLA_LWLA_H */
diff --git a/hardware/sysclk-lwla/protocol.c b/hardware/sysclk-lwla/protocol.c
index 0aa0406f..5b3dd6fc 100644
--- a/hardware/sysclk-lwla/protocol.c
+++ b/hardware/sysclk-lwla/protocol.c
@@ -18,23 +18,912 @@
  */
 
 #include "protocol.h"
+#include <string.h>
 
-SR_PRIV int sysclk_lwla_receive_data(int fd, int revents, void *cb_data)
+/* Bit mask covering all 34 channels. */
+#define ALL_CHANNELS_MASK (((uint64_t)1 << NUM_PROBES) - 1)
+
+/* Bit mask for the RLE repeat-count-follows flag. */
+#define RLE_FLAG_LEN_FOLLOWS ((uint64_t)1 << 35)
+
+/* Start address of capture status memory area to read. */
+#define CAP_STAT_ADDR 5
+
+/* Number of 64-bit words read from the capture status memory. */
+#define CAP_STAT_LEN 5
+
+/* The bitstream filenames are indexed by the clock source enumeration.
+ */
+static const char *const bitstream_map[] = {
+	FIRMWARE_DIR "/sysclk-lwla1034-off.bitstream",
+	FIRMWARE_DIR "/sysclk-lwla1034-int.bitstream",
+	FIRMWARE_DIR "/sysclk-lwla1034-extpos.bitstream",
+	FIRMWARE_DIR "/sysclk-lwla1034-extneg.bitstream",
+};
+
+/* Submit an already filled-in USB transfer.
+ */
+static int submit_transfer(struct dev_context *devc,
+			   struct libusb_transfer *xfer)
+{
+	int ret;
+
+	ret = libusb_submit_transfer(xfer);
+
+	if (ret != 0) {
+		sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
+		devc->transfer_error = TRUE;
+		return SR_ERR;
+	}
+
+	return SR_OK;
+}
+
+/* Set up the LWLA in preparation for an acquisition session.
+ */
+static int capture_setup(const struct sr_dev_inst *sdi)
 {
-	const struct sr_dev_inst *sdi;
 	struct dev_context *devc;
+	uint64_t divider_count;
+	uint64_t memory_limit;
+	uint16_t command[3 + 10*4];
 
-	(void)fd;
+	devc = sdi->priv;
 
-	if (!(sdi = cb_data))
-		return TRUE;
+	command[0] = LWLA_WORD(CMD_CAP_SETUP);
+	command[1] = LWLA_WORD(0); /* address */
+	command[2] = LWLA_WORD(10); /* length */
+
+	command[3] = LWLA_WORD_0(devc->channel_mask);
+	command[4] = LWLA_WORD_1(devc->channel_mask);
+	command[5] = LWLA_WORD_2(devc->channel_mask);
+	command[6] = LWLA_WORD_3(devc->channel_mask);
+
+	/* Set the clock divide counter maximum for samplerates of up to
+	 * 100 MHz. At the highest samplerate of 125 MHz the clock divider
+	 * is bypassed.
+	 */
+	if (devc->samplerate > 0 && devc->samplerate < SR_MHZ(100))
+		divider_count = SR_MHZ(100) / devc->samplerate - 1;
+	else
+		divider_count = 0;
+
+	command[7]  = LWLA_WORD_0(divider_count);
+	command[8]  = LWLA_WORD_1(divider_count);
+	command[9]  = LWLA_WORD_2(divider_count);
+	command[10] = LWLA_WORD_3(divider_count);
+
+	command[11] = LWLA_WORD_0(devc->trigger_values);
+	command[12] = LWLA_WORD_1(devc->trigger_values);
+	command[13] = LWLA_WORD_2(devc->trigger_values);
+	command[14] = LWLA_WORD_3(devc->trigger_values);
+
+	command[15] = LWLA_WORD_0(devc->trigger_edge_mask);
+	command[16] = LWLA_WORD_1(devc->trigger_edge_mask);
+	command[17] = LWLA_WORD_2(devc->trigger_edge_mask);
+	command[18] = LWLA_WORD_3(devc->trigger_edge_mask);
+
+	command[19] = LWLA_WORD_0(devc->trigger_mask);
+	command[20] = LWLA_WORD_1(devc->trigger_mask);
+	command[21] = LWLA_WORD_2(devc->trigger_mask);
+	command[22] = LWLA_WORD_3(devc->trigger_mask);
+
+	/* Set the capture memory full threshold. This is slightly less
+	 * than the actual maximum, most likely in order to compensate for
+	 * pipeline latency.
+	 */
+	memory_limit = MEMORY_DEPTH - 16;
+
+	command[23] = LWLA_WORD_0(memory_limit);
+	command[24] = LWLA_WORD_1(memory_limit);
+	command[25] = LWLA_WORD_2(memory_limit);
+	command[26] = LWLA_WORD_3(memory_limit);
+
+	/* Fill remaining 64-bit words with zeroes. */
+	memset(&command[27], 0, 16 * sizeof(uint16_t));
+
+	return lwla_send_command(sdi->conn, command, G_N_ELEMENTS(command));
+}
+
+/* Issue a register write command as an asynchronous USB transfer.
+ */
+static int issue_write_reg(const struct sr_dev_inst *sdi,
+			   unsigned int reg, unsigned int value)
+{
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
+
+	acq->xfer_buf_out[0] = LWLA_WORD(CMD_WRITE_REG);
+	acq->xfer_buf_out[1] = LWLA_WORD(reg);
+	acq->xfer_buf_out[2] = LWLA_WORD_0(value);
+	acq->xfer_buf_out[3] = LWLA_WORD_1(value);
+
+	acq->xfer_out->length = 4 * sizeof(uint16_t);
+
+	return submit_transfer(devc, acq->xfer_out);
+}
+
+/* Issue a register write command as an asynchronous USB transfer for the
+ * next register/value pair of the currently active register write sequence.
+ */
+static int issue_next_write_reg(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct regval_pair *regval;
+	int ret;
+
+	devc = sdi->priv;
+
+	if (devc->reg_write_pos >= devc->reg_write_len) {
+		sr_err("Already written all registers in sequence.");
+		return SR_ERR_BUG;
+	}
+	regval = &devc->reg_write_seq[devc->reg_write_pos];
+
+	ret = issue_write_reg(sdi, regval->reg, regval->val);
+	if (ret != SR_OK)
+		return ret;
+
+	++devc->reg_write_pos;
+	return SR_OK;
+}
+
+/* Issue a capture status request as an asynchronous USB transfer.
+ */
+static void request_capture_status(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
+
+	acq->xfer_buf_out[0] = LWLA_WORD(CMD_CAP_STATUS);
+	acq->xfer_buf_out[1] = LWLA_WORD(CAP_STAT_ADDR);
+	acq->xfer_buf_out[2] = LWLA_WORD(CAP_STAT_LEN);
+
+	acq->xfer_out->length = 3 * sizeof(uint16_t);
+
+	if (submit_transfer(devc, acq->xfer_out) == SR_OK)
+		devc->state = STATE_STATUS_REQUEST;
+}
+
+/* Issue a request for the capture buffer fill level as
+ * an asynchronous USB transfer.
+ */
+static void request_capture_length(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
+
+	acq->xfer_buf_out[0] = LWLA_WORD(CMD_READ_REG);
+	acq->xfer_buf_out[1] = LWLA_WORD(REG_MEM_FILL);
+
+	acq->xfer_out->length = 2 * sizeof(uint16_t);
+
+	if (submit_transfer(devc, acq->xfer_out) == SR_OK)
+		devc->state = STATE_LENGTH_REQUEST;
+}
+
+/* Initiate the capture memory read operation:  Reset the acquisition state
+ * and start a sequence of register writes in order to set up the device for
+ * reading from the capture buffer.
+ */
+static void issue_read_start(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+	struct regval_pair *regvals;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
+
+	/* Reset RLE state. */
+	acq->rle = RLE_STATE_DATA;
+	acq->sample  = 0;
+	acq->run_len = 0;
+
+	acq->captured_samples    = 0;
+	acq->transferred_samples = 0;
+
+	/* For some reason, the start address is 4 rather than 0. */
+	acq->mem_addr_done = 4;
+	acq->mem_addr_next = 4;
+	acq->mem_addr_stop = acq->mem_addr_fill;
+
+	/* Byte offset into the packet output buffer. */
+	acq->out_offset = 0;
+
+	regvals = devc->reg_write_seq;
+
+	regvals[0].reg = REG_DIV_BYPASS;
+	regvals[0].val = 1;
+
+	regvals[1].reg = REG_MEM_CTRL2;
+	regvals[1].val = 2;
+
+	regvals[2].reg = REG_MEM_CTRL4;
+	regvals[2].val = 4;
+
+	devc->reg_write_pos = 0;
+	devc->reg_write_len = 3;
+
+	if (issue_next_write_reg(sdi) == SR_OK)
+		devc->state = STATE_READ_PREPARE;
+}
+
+static void issue_read_end(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+
+	devc = sdi->priv;
+
+	if (issue_write_reg(sdi, REG_DIV_BYPASS, 0) == SR_OK)
+		devc->state = STATE_READ_END;
+}
+
+/* Decode an incoming reponse to a buffer fill level request and act on it
+ * as appropriate.  Note that this function changes the device context state.
+ */
+static void process_capture_length(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
+
+	if (acq->xfer_in->actual_length != 4) {
+		sr_err("Received size %d doesn't match expected size 4.",
+		       acq->xfer_in->actual_length);
+		devc->transfer_error = TRUE;
+		return;
+	}
+	acq->mem_addr_fill = LWLA_READ32(acq->xfer_buf_in);
+
+	sr_dbg("%lu words in capture buffer.",
+	       (unsigned long)acq->mem_addr_fill);
+
+	if (acq->mem_addr_fill > 0 && sdi->status == SR_ST_ACTIVE)
+		issue_read_start(sdi);
+	else
+		issue_read_end(sdi);
+}
+
+/* Initiate a sequence of register write commands with the effect of
+ * cancelling a running capture operation.  This sets a new device state
+ * if issuing the first command succeeds.
+ */
+static void issue_stop_capture(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct regval_pair *regvals;
+
+	devc = sdi->priv;
+
+	if (devc->stopping_in_progress)
+		return;
+
+	regvals = devc->reg_write_seq;
+
+	regvals[0].reg = REG_CMD_CTRL2;
+	regvals[0].val = 10;
+
+	regvals[1].reg = REG_CMD_CTRL3;
+	regvals[1].val = 0;
+
+	regvals[2].reg = REG_CMD_CTRL4;
+	regvals[2].val = 0;
+
+	regvals[3].reg = REG_CMD_CTRL1;
+	regvals[3].val = 0;
+
+	regvals[4].reg = REG_DIV_BYPASS;
+	regvals[4].val = 0;
+
+	devc->reg_write_pos = 0;
+	devc->reg_write_len = 5;
+
+	if (issue_next_write_reg(sdi) == SR_OK) {
+		devc->stopping_in_progress = TRUE;
+		devc->state = STATE_STOP_CAPTURE;
+	}
+}
+
+/* Decode an incoming capture status reponse and act on it as appropriate.
+ * Note that this function changes the device state.
+ */
+static void process_capture_status(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
+
+	if (acq->xfer_in->actual_length != CAP_STAT_LEN * 8) {
+		sr_err("Received size %d doesn't match expected size %d.",
+		       acq->xfer_in->actual_length, CAP_STAT_LEN * 8);
+		devc->transfer_error = TRUE;
+		return;
+	}
+
+	/* TODO: Find out the actual bit width of these fields as stored
+	 * in the FPGA.  These fields are definitely less than 64 bit wide
+	 * internally, and the unused bits occasionally even contain garbage.
+	 */
+	acq->mem_addr_fill    = LWLA_READ32(&acq->xfer_buf_in[0]);
+	acq->captured_samples = LWLA_READ32(&acq->xfer_buf_in[8])
+				* (uint64_t)100000;
+	acq->capture_flags    = LWLA_READ32(&acq->xfer_buf_in[16])
+				& STATUS_FLAG_MASK;
+
+	sr_spew("Captured %lu words, %" PRIu64 " samples, flags 0x%02X",
+		(unsigned long)acq->mem_addr_fill,
+		acq->captured_samples, acq->capture_flags);
+
+	if (acq->captured_samples >= devc->limit_samples) {
+		issue_stop_capture(sdi);
+		return;
+	}
+	devc->state = STATE_STATUS_WAIT;
+
+	if ((acq->capture_flags & STATUS_TRIGGERED) == 0) {
+		sr_spew("Waiting for trigger.");
+	} else if ((acq->capture_flags & STATUS_MEM_AVAIL) == 0) {
+		sr_dbg("Capture memory filled.");
+		request_capture_length(sdi);
+	} else if ((acq->capture_flags & STATUS_CAPTURING) != 0) {
+		sr_spew("Sampling in progress.");
+	}
+}
+
+/* Issue a capture buffer read request as an asynchronous USB transfer.
+ * The address and size of the memory area to read are derived from the
+ * current acquisition state.
+ */
+static void request_read_mem(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+	size_t count;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
+
+	if (acq->mem_addr_next >= acq->mem_addr_stop)
+		return;
+
+	/* Always read a multiple of 8 device words. */
+	count = (acq->mem_addr_stop - acq->mem_addr_next + 7) / 8 * 8;
+	count = MIN(count, READ_CHUNK_LEN);
+
+	acq->xfer_buf_out[0] = LWLA_WORD(CMD_READ_MEM);
+	acq->xfer_buf_out[1] = LWLA_WORD_0(acq->mem_addr_next);
+	acq->xfer_buf_out[2] = LWLA_WORD_1(acq->mem_addr_next);
+	acq->xfer_buf_out[3] = LWLA_WORD_0(count);
+	acq->xfer_buf_out[4] = LWLA_WORD_1(count);
+
+	acq->xfer_out->length = 5 * sizeof(uint16_t);
+
+	if (submit_transfer(devc, acq->xfer_out) == SR_OK) {
+		acq->mem_addr_next += count;
+		devc->state = STATE_READ_REQUEST;
+	}
+}
+
+/* Send a packet of logic samples to the session bus.  The payload is taken
+ * from the acquisition state.  The return value indicates whether to stop
+ * reading more samples.
+ */
+static gboolean send_logic_packet(const struct sr_dev_inst *sdi)
+{
+	uint64_t samples;
+	struct dev_context *devc;
+	struct acquisition_state *acq;
+	struct sr_datafeed_packet packet;
+	struct sr_datafeed_logic  logic;
+	int last;
+
+	devc = sdi->priv;
+	acq  = devc->acquisition;
 
-	if (!(devc = sdi->priv))
+	if (acq->transferred_samples >= devc->limit_samples)
 		return TRUE;
 
-	if (revents == G_IO_IN) {
-		/* TODO */
+	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;
+		}
 	}
+	return SR_OK;
+}
+
+/* Configure the LWLA in preparation for an acquisition session.
+ */
+SR_PRIV int lwla_setup_acquisition(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct sr_usb_dev_inst *usb;
+	struct regval_pair regvals[7];
+	int ret;
+
+	devc = sdi->priv;
+	usb  = sdi->conn;
+
+	regvals[0].reg = REG_MEM_CTRL2;
+	regvals[0].val = 2;
+
+	regvals[1].reg = REG_MEM_CTRL2;
+	regvals[1].val = 1;
+
+	regvals[2].reg = REG_CMD_CTRL2;
+	regvals[2].val = 10;
+
+	regvals[3].reg = REG_CMD_CTRL3;
+	regvals[3].val = 0x74;
+
+	regvals[4].reg = REG_CMD_CTRL4;
+	regvals[4].val = 0;
+
+	regvals[5].reg = REG_CMD_CTRL1;
+	regvals[5].val = 0;
+
+	regvals[6].reg = REG_DIV_BYPASS;
+	regvals[6].val = (devc->samplerate > SR_MHZ(100)) ? 1 : 0;
+
+	ret = lwla_write_regs(usb, regvals, G_N_ELEMENTS(regvals));
+	if (ret != SR_OK)
+		return ret;
+
+	return capture_setup(sdi);
+}
+
+/* Start the capture operation on the LWLA device.  Beginning with this
+ * function, all USB transfers will be asynchronous until the end of the
+ * acquisition session.
+ */
+SR_PRIV int lwla_start_acquisition(const struct sr_dev_inst *sdi)
+{
+	struct dev_context *devc;
+	struct sr_usb_dev_inst *usb;
+	struct acquisition_state *acq;
+	struct regval_pair *regvals;
+
+	devc = sdi->priv;
+	usb  = sdi->conn;
+	acq  = devc->acquisition;
+
+	libusb_fill_bulk_transfer(acq->xfer_out, usb->devhdl, EP_COMMAND,
+				  (unsigned char *)acq->xfer_buf_out, 0,
+				  &receive_transfer_out,
+				  (struct sr_dev_inst *)sdi, USB_TIMEOUT);
+
+	libusb_fill_bulk_transfer(acq->xfer_in, usb->devhdl, EP_REPLY,
+				  (unsigned char *)acq->xfer_buf_in,
+				  sizeof acq->xfer_buf_in,
+				  &receive_transfer_in,
+				  (struct sr_dev_inst *)sdi, USB_TIMEOUT);
+
+	regvals = devc->reg_write_seq;
+
+	regvals[0].reg = REG_CMD_CTRL2;
+	regvals[0].val = 10;
+
+	regvals[1].reg = REG_CMD_CTRL3;
+	regvals[1].val = 1;
+
+	regvals[2].reg = REG_CMD_CTRL4;
+	regvals[2].val = 0;
+
+	regvals[3].reg = REG_CMD_CTRL1;
+	regvals[3].val = 0;
+
+	devc->reg_write_pos = 0;
+	devc->reg_write_len = 4;
+
+	devc->state = STATE_START_CAPTURE;
+
+	return issue_next_write_reg(sdi);
+}
+
+/* Allocate an acquisition state object.
+ */
+SR_PRIV struct acquisition_state *lwla_alloc_acquisition_state(void)
+{
+	struct acquisition_state *acq;
+
+	acq = g_try_new0(struct acquisition_state, 1);
+	if (!acq) {
+		sr_err("Acquisition state malloc failed.");
+		return NULL;
+	}
+
+	acq->xfer_in = libusb_alloc_transfer(0);
+	if (!acq->xfer_in) {
+		sr_err("Transfer malloc failed.");
+		g_free(acq);
+		return NULL;
+	}
+
+	acq->xfer_out = libusb_alloc_transfer(0);
+	if (!acq->xfer_out) {
+		sr_err("Transfer malloc failed.");
+		libusb_free_transfer(acq->xfer_in);
+		g_free(acq);
+		return NULL;
+	}
+
+	return acq;
+}
+
+/* Deallocate an acquisition state object.
+ */
+SR_PRIV void lwla_free_acquisition_state(struct acquisition_state *acq)
+{
+	if (acq) {
+		libusb_free_transfer(acq->xfer_out);
+		libusb_free_transfer(acq->xfer_in);
+		g_free(acq);
+	}
+}
+
+/* USB I/O source callback.
+ */
+SR_PRIV int lwla_receive_data(int fd, int revents, void *cb_data)
+{
+	struct sr_dev_inst *sdi;
+	struct dev_context *devc;
+	struct drv_context *drvc;
+	struct timeval tv;
+	int ret;
+
+	(void)fd;
+
+	sdi  = cb_data;
+	devc = sdi->priv;
+	drvc = sdi->driver->priv;
+
+	if (!devc || !drvc)
+		return FALSE;
+
+	/* No timeout: return immediately. */
+	tv.tv_sec  = 0;
+	tv.tv_usec = 0;
+
+	ret = libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx,
+						     &tv, NULL);
+	if (ret != 0)
+		sr_err("Event handling failed: %s.", libusb_error_name(ret));
+
+	/* If no event flags are set the timeout must have expired. */
+	if (revents == 0 && devc->state == STATE_STATUS_WAIT) {
+		if (sdi->status == SR_ST_STOPPING)
+			issue_stop_capture(sdi);
+		else
+			request_capture_status(sdi);
+	}
+
+	/* Check if an error occurred on a transfer. */
+	if (devc->transfer_error)
+		end_acquisition(sdi);
 
 	return TRUE;
 }
diff --git a/hardware/sysclk-lwla/protocol.h b/hardware/sysclk-lwla/protocol.h
index dd3e8b3b..be8aaeba 100644
--- a/hardware/sysclk-lwla/protocol.h
+++ b/hardware/sysclk-lwla/protocol.h
@@ -20,26 +20,194 @@
 #ifndef LIBSIGROK_HARDWARE_SYSCLK_LWLA_PROTOCOL_H
 #define LIBSIGROK_HARDWARE_SYSCLK_LWLA_PROTOCOL_H
 
-#include <stdint.h>
-#include <glib.h>
+/* Message logging helpers with subsystem-specific prefix string. */
+#define LOG_PREFIX "sysclk-lwla"
+
+#include "lwla.h"
 #include "libsigrok.h"
 #include "libsigrok-internal.h"
+#include <stdint.h>
+#include <glib.h>
 
-/* Message logging helpers with subsystem-specific prefix string. */
-#define LOG_PREFIX "sysclk-lwla"
+/* For now, only the LWLA1034 is supported.
+ */
+#define VENDOR_NAME	"SysClk"
+#define MODEL_NAME	"LWLA1034"
+
+#define USB_VID_PID	"2961.6689"
+#define USB_INTERFACE	0
+#define USB_TIMEOUT	3000 /* ms */
+
+#define NUM_PROBES	34
+#define TRIGGER_TYPES	"01fr"
+
+/** Unit and packet size for the sigrok logic datafeed.
+ */
+#define UNIT_SIZE	((NUM_PROBES + 7) / 8)
+#define PACKET_SIZE	(10000 * UNIT_SIZE)	/* bytes */
+
+/** Size of the acquisition buffer in device memory units.
+ */
+#define MEMORY_DEPTH	(256 * 1024)	/* 256k x 36 bit */
+
+/** Number of device memory units (36 bit) to read at a time.  Slices of 8
+ * consecutive 36-bit words are mapped to 9 32-bit words each, so the chunk
+ * length should be a multiple of 8 to ensure alignment to slice boundaries.
+ *
+ * Experimentation has shown that reading chunks larger than about 1024 bytes
+ * is unreliable.  The threshold seems to relate to the buffer size on the FX2
+ * USB chip:  The configured endpoint buffer size is 512, and with double or
+ * triple buffering enabled a multiple of 512 bytes can be kept in fly.
+ *
+ * The vendor software limits reads to 120 words (15 slices, 540 bytes) at
+ * a time.  So far, it appears safe to increase this to 224 words (28 slices,
+ * 1008 bytes), thus making the most of two 512 byte buffers.
+ */
+#define READ_CHUNK_LEN	(28 * 8)
+
+/** Calculate the required buffer size in 16-bit units for reading a given
+ * number of device memory words.  Rounded to a multiple of 8 device words.
+ */
+#define LWLA1034_MEMBUF_LEN(count) (((count) + 7) / 8 * 18)
+
+/** Maximum number of 16-bit words sent at a time during acquisition.
+ * Used for allocating the libusb transfer buffer.
+ */
+#define MAX_ACQ_SEND_WORDS	8 /* 5 for memory read request plus stuffing */
+
+/** Maximum number of 16-bit words received at a time during acquisition.
+ * Round to the next multiple of the endpoint buffer size to avoid nasty
+ * transfer overflow conditions on hiccups.
+ */
+#define MAX_ACQ_RECV_WORDS	((READ_CHUNK_LEN / 4 * 9 + 255) / 256 * 256)
+
+/** Maximum length of a register write sequence.
+ */
+#define MAX_REG_WRITE_SEQ_LEN   5
+
+/** Default configured samplerate.
+ */
+#define DEFAULT_SAMPLERATE	SR_MHZ(125)
+
+/** LWLA clock sources.
+ */
+enum clock_source {
+	CLOCK_SOURCE_NONE,
+	CLOCK_SOURCE_INT,
+	CLOCK_SOURCE_EXT_RISE,
+	CLOCK_SOURCE_EXT_FALL,
+};
+
+/** LWLA device states.
+ */
+enum device_state {
+	STATE_IDLE = 0,
+
+	STATE_START_CAPTURE,
+
+	STATE_STATUS_WAIT,
+	STATE_STATUS_REQUEST,
+	STATE_STATUS_RESPONSE,
+
+	STATE_STOP_CAPTURE,
+
+	STATE_LENGTH_REQUEST,
+	STATE_LENGTH_RESPONSE,
+
+	STATE_READ_PREPARE,
+	STATE_READ_REQUEST,
+	STATE_READ_RESPONSE,
+	STATE_READ_END,
+};
+
+/** LWLA run-length encoding states.
+ */
+enum rle_state {
+	RLE_STATE_DATA,
+	RLE_STATE_LEN
+};
+
+/** LWLA sample acquisition and decompression state.
+ */
+struct acquisition_state {
+	uint64_t sample;
+	uint64_t run_len;
+
+	/** Number of samples acquired so far. */
+	uint64_t captured_samples;
+	/** Number of samples sent to the session bus. */
+	uint64_t transferred_samples;
+
+	/** Capture memory fill level. */
+	size_t mem_addr_fill;
 
-/** Private, per-device-instance driver context. */
+	size_t mem_addr_done;
+	size_t mem_addr_next;
+	size_t mem_addr_stop;
+
+	size_t out_offset;
+
+	struct libusb_transfer *xfer_in;
+	struct libusb_transfer *xfer_out;
+
+	unsigned int capture_flags;
+
+	enum rle_state rle;
+
+	/* Payload data buffers for outgoing and incoming transfers. */
+	uint16_t xfer_buf_out[MAX_ACQ_SEND_WORDS];
+	uint16_t xfer_buf_in[MAX_ACQ_RECV_WORDS];
+
+	/* Payload buffer for sigrok logic packets. */
+	uint8_t out_packet[PACKET_SIZE];
+};
+
+/** Private, per-device-instance driver context.
+ */
 struct dev_context {
-	/* Model-specific information */
+	/** The samplerate selected by the user. */
+	uint64_t samplerate;
+
+	/** The maximimum number of samples to acquire. */
+	uint64_t limit_samples;
+
+	/** Channels to use. */
+	uint64_t channel_mask;
+
+	uint64_t trigger_mask;
+	uint64_t trigger_edge_mask;
+	uint64_t trigger_values;
 
-	/* Acquisition settings */
+	struct acquisition_state *acquisition;
 
-	/* Operational state */
+	struct regval_pair reg_write_seq[MAX_REG_WRITE_SEQ_LEN];
+	int reg_write_pos;
+	int reg_write_len;
 
-	/* Temporary state across callbacks */
+	enum device_state state;
+	enum device_state next_state;
 
+	/** The currently configured clock source of the device. */
+	enum clock_source cur_clock_source;
+	/** The clock source selected by the user. */
+	enum clock_source selected_clock_source;
+
+	/* Indicates that stopping the acquisition is currently in progress. */
+	gboolean stopping_in_progress;
+
+	/* Indicates whether a transfer failed. */
+	gboolean transfer_error;
 };
 
-SR_PRIV int sysclk_lwla_receive_data(int fd, int revents, void *cb_data);
+SR_PRIV struct acquisition_state *lwla_alloc_acquisition_state(void);
+SR_PRIV void lwla_free_acquisition_state(struct acquisition_state *acq);
+
+SR_PRIV int lwla_init_device(const struct sr_dev_inst *sdi);
+SR_PRIV int lwla_set_clock_source(const struct sr_dev_inst *sdi);
+SR_PRIV int lwla_setup_acquisition(const struct sr_dev_inst *sdi);
+SR_PRIV int lwla_start_acquisition(const struct sr_dev_inst *sdi);
+SR_PRIV int lwla_abort_acquisition(const struct sr_dev_inst *sdi);
+
+SR_PRIV int lwla_receive_data(int fd, int revents, void *cb_data);
 
-#endif
+#endif /* !LIBSIGROK_HARDWARE_SYSCLK_LWLA_PROTOCOL_H */