jtag: add opendous and estick support

Change-Id: I49c25d226f05fdcaca6cbfc35c2ab47e8464abec
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Reviewed-on: http://openocd.zylin.com/611
Tested-by: jenkins

8 files changed, 814 insertions, 1 deletions

diff --git a/configure.ac b/configure.ac
index 7b82be1..4d7b7d7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -478,6 +478,10 @@ AC_ARG_ENABLE([osbdm],
   AS_HELP_STRING([--enable-osbdm], [Enable building support for the OSBDM (JTAG only) Programmer]),
   [build_osbdm=$enableval], [build_osbdm=no])
 
+AC_ARG_ENABLE([opendous],
+  AS_HELP_STRING([--enable-opendous], [Enable building support for the estick/opendous JTAG Programmer]),
+  [build_opendous=$enableval], [build_opendous=no])
+
 AC_ARG_ENABLE([minidriver_dummy],
   AS_HELP_STRING([--enable-minidriver-dummy], [Enable the dummy minidriver.]),
   [build_minidriver_dummy=$enableval], [build_minidriver_dummy=no])
@@ -783,6 +787,12 @@ else
   AC_DEFINE([BUILD_OSBDM], [0], [0 if you don't want the OSBDM driver.])
 fi
 
+if test $build_opendous = yes; then
+  AC_DEFINE([BUILD_OPENDOUS], [1], [1 if you want the estick/opendous JTAG driver.])
+else
+  AC_DEFINE([BUILD_OPENDOUS], [0], [0 if you don't want the estick/opendous JTAG driver.])
+fi
+
 if test "$use_internal_jimtcl" = yes; then
   if test -f "$srcdir/jimtcl/configure.ac"; then
     AX_CONFIG_SUBDIR_OPTION([jimtcl], [--disable-install-jim])
@@ -1069,7 +1079,9 @@ fi
 
 # Check for libusb1 ported drivers.
 build_usb_ng=no
-if test $build_jlink = yes -o $build_stlink = yes -o $build_osbdm = yes; then
+if test $build_jlink = yes -o $build_stlink = yes -o $build_osbdm = yes -o \
+  $build_opendous = yes
+then
   build_usb_ng=yes
 fi
 
@@ -1118,6 +1130,7 @@ AM_CONDITIONAL([REMOTE_BITBANG], [test $build_remote_bitbang = yes])
 AM_CONDITIONAL([BUSPIRATE], [test $build_buspirate = yes])
 AM_CONDITIONAL([STLINK], [test $build_stlink = yes])
 AM_CONDITIONAL([OSBDM], [test $build_osbdm = yes])
+AM_CONDITIONAL([OPENDOUS], [test $build_opendous = yes])
 AM_CONDITIONAL([USB], [test $build_usb = yes])
 AM_CONDITIONAL([USB_NG], [test $build_usb_ng = yes])
 AM_CONDITIONAL([USE_LIBUSB0], [test $use_libusb0 = yes])
diff --git a/contrib/openocd.udev b/contrib/openocd.udev
index 998bddf..5d4e639 100644
--- a/contrib/openocd.udev
+++ b/contrib/openocd.udev
@@ -83,4 +83,7 @@ ATTRS{idVendor}=="0483", ATTRS{idProduct}=="3744", MODE="664", GROUP="plugdev"
 # stlink v2
 ATTRS{idVendor}=="0483", ATTRS{idProduct}=="3748", MODE="664", GROUP="plugdev"
 
+# opendous and estick
+ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="204f", MODE="664", GROUP="plugdev"
+
 LABEL="openocd_rules_end"
diff --git a/doc/openocd.texi b/doc/openocd.texi
index 3134afd..c32f28e 100644
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -461,6 +461,12 @@ The simplest solution is to get linux to ignore the ST-LINK using one of the fol
 
 @item @b{Buspirate}
 @* Link: @url{http://dangerousprototypes.com/bus-pirate-manual/}
+
+@item @b{opendous}
+@* Link: @url{http://code.google.com/p/opendous-jtag/}
+
+@item @b{estick}
+@* Link: @url{http://code.google.com/p/estick-jtag/}
 @end itemize
 
 @section IBM PC Parallel Printer Port Based
@@ -2693,6 +2699,10 @@ Manually sets the stlink api used, valid options are 1 or 2.
 @end deffn
 @end deffn
 
+@deffn {Interface Driver} {opendous}
+opendous-jtag is a freely programmable USB adapter.
+@end deffn
+
 @deffn {Interface Driver} {ZY1000}
 This is the Zylin ZY1000 JTAG debugger.
 @end deffn
diff --git a/src/jtag/drivers/Makefile.am b/src/jtag/drivers/Makefile.am
index 459027f..f977d42 100644
--- a/src/jtag/drivers/Makefile.am
+++ b/src/jtag/drivers/Makefile.am
@@ -101,6 +101,9 @@ endif
 if OSBDM
 DRIVERFILES += osbdm.c
 endif
+if OPENDOUS
+DRIVERFILES += opendous.c
+endif
 
 noinst_HEADERS = \
 	bitbang.h \
diff --git a/src/jtag/drivers/opendous.c b/src/jtag/drivers/opendous.c
new file mode 100644
index 0000000..c973bd2
--- /dev/null
+++ b/src/jtag/drivers/opendous.c
@@ -0,0 +1,764 @@
+/***************************************************************************
+ *                                                                         *
+ *   Copyright (C) 2009 by Cahya Wirawan <cahya@gmx.at>                    *
+ *   Based on opendous driver by Vladimir Fonov                            *
+ *                                                                         *
+ *   Copyright (C) 2009 by Vladimir Fonov <vladimir.fonov@gmai.com>        *
+ *   Based on J-link driver by  Juergen Stuber                             *
+ *                                                                         *
+ *   Copyright (C) 2007 by Juergen Stuber <juergen@jstuber.net>            *
+ *   based on Dominic Rath's and Benedikt Sauter's usbprog.c               *
+ *                                                                         *
+ *   Copyright (C) 2008 by Spencer Oliver                                  *
+ *   spen@spen-soft.co.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  *
+ *   the Free Software Foundation; either version 2 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, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <jtag/interface.h>
+#include <jtag/commands.h>
+#include "libusb_common.h"
+#include <string.h>
+#include <sys/timeb.h>
+#include <time.h>
+
+#define ESTICK_VID 0x1781
+#define ESTICK_PID 0xC0C0
+
+#define OPENDOUS_VID 0x03EB
+#define OPENDOUS_PID 0x204F
+
+/* pid could be specified at runtime */
+static uint16_t vids[] = { OPENDOUS_VID, ESTICK_VID, 0 };
+static uint16_t pids[] = { OPENDOUS_PID, ESTICK_PID, 0 };
+
+#define OPENDOUS_WRITE_ENDPOINT   0x02
+#define OPENDOUS_READ_ENDPOINT    0x81
+
+static unsigned int opendous_hw_jtag_version = 1;
+
+#define OPENDOUS_USB_TIMEOUT      1000
+
+#define OPENDOUS_USB_BUFFER_SIZE  360
+#define OPENDOUS_IN_BUFFER_SIZE   (OPENDOUS_USB_BUFFER_SIZE)
+#define OPENDOUS_OUT_BUFFER_SIZE  (OPENDOUS_USB_BUFFER_SIZE)
+
+/* Global USB buffers */
+static uint8_t usb_in_buffer[OPENDOUS_IN_BUFFER_SIZE];
+static uint8_t usb_out_buffer[OPENDOUS_OUT_BUFFER_SIZE];
+
+/* Constants for OPENDOUS command */
+
+#define OPENDOUS_MAX_SPEED			66
+#define OPENDOUS_MAX_TAP_TRANSMIT	350	/* even number is easier to handle */
+#define OPENDOUS_MAX_INPUT_DATA		(OPENDOUS_MAX_TAP_TRANSMIT*4)
+
+#define OPENDOUS_TAP_BUFFER_SIZE 65536
+
+#define MAX_PENDING_SCAN_RESULTS (OPENDOUS_MAX_INPUT_DATA)
+
+/* JTAG usb commands */
+#define JTAG_CMD_TAP_OUTPUT		0x0
+#define JTAG_CMD_SET_TRST		0x1
+#define JTAG_CMD_SET_SRST		0x2
+#define JTAG_CMD_READ_INPUT		0x3
+#define JTAG_CMD_TAP_OUTPUT_EMU	0x4
+#define JTAG_CMD_SET_DELAY		0x5
+#define JTAG_CMD_SET_SRST_TRST	0x6
+#define JTAG_CMD_READ_CONFIG	0x7
+
+/* External interface functions */
+static int opendous_execute_queue(void);
+static int opendous_speed(int speed);
+static int opendous_speed_div(int speed, int *khz);
+static int opendous_khz(int khz, int *jtag_speed);
+static int opendous_init(void);
+static int opendous_quit(void);
+
+/* Queue command functions */
+static void opendous_end_state(tap_state_t state);
+static void opendous_state_move(void);
+static void opendous_path_move(int num_states, tap_state_t *path);
+static void opendous_runtest(int num_cycles);
+static void opendous_scan(int ir_scan, enum scan_type type, uint8_t *buffer,
+		int scan_size, struct scan_command *command);
+static void opendous_reset(int trst, int srst);
+static void opendous_simple_command(uint8_t command, uint8_t _data);
+static int opendous_get_status(void);
+
+/* opendous tap buffer functions */
+static void opendous_tap_init(void);
+static int opendous_tap_execute(void);
+static void opendous_tap_ensure_space(int scans, int bits);
+static void opendous_tap_append_step(int tms, int tdi);
+static void opendous_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command);
+
+/* opendous lowlevel functions */
+struct opendous_jtag {
+	struct jtag_libusb_device_handle *usb_handle;
+};
+
+static struct opendous_jtag *opendous_usb_open(void);
+static void opendous_usb_close(struct opendous_jtag *opendous_jtag);
+static int opendous_usb_message(struct opendous_jtag *opendous_jtag, int out_length, int in_length);
+static int opendous_usb_write(struct opendous_jtag *opendous_jtag, int out_length);
+static int opendous_usb_read(struct opendous_jtag *opendous_jtag);
+
+/* helper functions */
+int opendous_get_version_info(void);
+
+#ifdef _DEBUG_USB_COMMS_
+char time_str[50];
+static void opendous_debug_buffer(uint8_t *buffer, int length);
+char *opendous_get_time(char *);
+#endif
+
+static struct opendous_jtag *opendous_jtag_handle;
+
+/***************************************************************************/
+/* External interface implementation */
+
+COMMAND_HANDLER(opendous_handle_opendous_info_command)
+{
+	if (opendous_get_version_info() == ERROR_OK) {
+		/* attempt to get status */
+		opendous_get_status();
+	}
+
+	return ERROR_OK;
+}
+
+COMMAND_HANDLER(opendous_handle_opendous_hw_jtag_command)
+{
+	switch (CMD_ARGC) {
+		case 0:
+			command_print(CMD_CTX, "opendous hw jtag  %i", opendous_hw_jtag_version);
+			break;
+
+		case 1: {
+			int request_version = atoi(CMD_ARGV[0]);
+			switch (request_version) {
+				case 2:
+				case 3:
+					opendous_hw_jtag_version = request_version;
+					break;
+
+			default:
+				return ERROR_COMMAND_SYNTAX_ERROR;
+			}
+			break;
+		}
+
+		default:
+			return ERROR_COMMAND_SYNTAX_ERROR;
+	}
+
+	return ERROR_OK;
+}
+
+static const struct command_registration opendous_command_handlers[] = {
+	{
+		.name = "opendous_info",
+		.handler = &opendous_handle_opendous_info_command,
+		.mode = COMMAND_EXEC,
+		.help = "show opendous info",
+	},
+	{
+		.name = "opendous_hw_jtag",
+		.handler = &opendous_handle_opendous_hw_jtag_command,
+		.mode = COMMAND_EXEC,
+		.help = "access opendous HW JTAG command version",
+		.usage = "[2|3]",
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+struct jtag_interface opendous_interface = {
+	.name = "opendous",
+	.commands = opendous_command_handlers,
+	.execute_queue = opendous_execute_queue,
+	.speed = opendous_speed,
+	.speed_div = opendous_speed_div,
+	.khz = opendous_khz,
+	.init = opendous_init,
+	.quit = opendous_quit,
+};
+
+static int opendous_execute_queue(void)
+{
+	struct jtag_command *cmd = jtag_command_queue;
+	int scan_size;
+	enum scan_type type;
+	uint8_t *buffer;
+
+	while (cmd != NULL) {
+		switch (cmd->type) {
+			case JTAG_RUNTEST:
+				DEBUG_JTAG_IO("runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, \
+					cmd->cmd.runtest->end_state);
+
+				if (cmd->cmd.runtest->end_state != -1)
+					opendous_end_state(cmd->cmd.runtest->end_state);
+				opendous_runtest(cmd->cmd.runtest->num_cycles);
+				break;
+
+			case JTAG_TLR_RESET:
+				DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
+
+				if (cmd->cmd.statemove->end_state != -1)
+					opendous_end_state(cmd->cmd.statemove->end_state);
+				opendous_state_move();
+				break;
+
+			case JTAG_PATHMOVE:
+				DEBUG_JTAG_IO("pathmove: %i states, end in %i", \
+					cmd->cmd.pathmove->num_states, \
+					cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
+
+				opendous_path_move(cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path);
+				break;
+
+			case JTAG_SCAN:
+				DEBUG_JTAG_IO("scan end in %i", cmd->cmd.scan->end_state);
+
+				if (cmd->cmd.scan->end_state != -1)
+					opendous_end_state(cmd->cmd.scan->end_state);
+
+				scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
+				DEBUG_JTAG_IO("scan input, length = %d", scan_size);
+
+#ifdef _DEBUG_USB_COMMS_
+				opendous_debug_buffer(buffer, (scan_size + 7) / 8);
+#endif
+				type = jtag_scan_type(cmd->cmd.scan);
+				opendous_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size, cmd->cmd.scan);
+				break;
+
+			case JTAG_RESET:
+				DEBUG_JTAG_IO("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
+
+				opendous_tap_execute();
+
+				if (cmd->cmd.reset->trst == 1)
+					tap_set_state(TAP_RESET);
+				opendous_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
+				break;
+
+			case JTAG_SLEEP:
+				DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
+				opendous_tap_execute();
+				jtag_sleep(cmd->cmd.sleep->us);
+				break;
+
+			default:
+				LOG_ERROR("BUG: unknown JTAG command type encountered");
+				exit(-1);
+		}
+		cmd = cmd->next;
+	}
+	return opendous_tap_execute();
+}
+
+/* Sets speed in kHz. */
+static int opendous_speed(int speed)
+{
+	if (speed <= OPENDOUS_MAX_SPEED) {
+		/* one day... */
+		return ERROR_OK;
+	} else
+		LOG_INFO("Requested speed %dkHz exceeds maximum of %dkHz, ignored", speed, OPENDOUS_MAX_SPEED);
+
+	return ERROR_OK;
+}
+
+static int opendous_speed_div(int speed, int *khz)
+{
+	*khz = speed;
+
+	return ERROR_OK;
+}
+
+static int opendous_khz(int khz, int *jtag_speed)
+{
+	*jtag_speed = khz;
+	/* TODO: convert this into delay value for opendous */
+
+	return ERROR_OK;
+}
+
+static int opendous_init(void)
+{
+	int check_cnt;
+
+	opendous_jtag_handle = opendous_usb_open();
+
+	if (opendous_jtag_handle == 0) {
+		LOG_ERROR("Cannot find opendous Interface! Please check connection and permissions.");
+		return ERROR_JTAG_INIT_FAILED;
+	}
+
+	check_cnt = 0;
+	while (check_cnt < 3) {
+		if (opendous_get_version_info() == ERROR_OK) {
+			/* attempt to get status */
+			opendous_get_status();
+			break;
+		}
+
+		check_cnt++;
+	}
+
+	LOG_INFO("opendous JTAG Interface ready");
+
+	opendous_reset(0, 0);
+	opendous_tap_init();
+
+	return ERROR_OK;
+}
+
+static int opendous_quit(void)
+{
+	opendous_usb_close(opendous_jtag_handle);
+	return ERROR_OK;
+}
+
+/***************************************************************************/
+/* Queue command implementations */
+
+void opendous_end_state(tap_state_t state)
+{
+	if (tap_is_state_stable(state))
+		tap_set_end_state(state);
+	else {
+		LOG_ERROR("BUG: %i is not a valid end state", state);
+		exit(-1);
+	}
+}
+
+/* Goes to the end state. */
+void opendous_state_move(void)
+{
+	int i;
+	int tms = 0;
+	uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
+	uint8_t tms_scan_bits = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
+
+	for (i = 0; i < tms_scan_bits; i++) {
+		tms = (tms_scan >> i) & 1;
+		opendous_tap_append_step(tms, 0);
+	}
+
+	tap_set_state(tap_get_end_state());
+}
+
+void opendous_path_move(int num_states, tap_state_t *path)
+{
+	int i;
+
+	for (i = 0; i < num_states; i++) {
+		if (path[i] == tap_state_transition(tap_get_state(), false))
+			opendous_tap_append_step(0, 0);
+		else if (path[i] == tap_state_transition(tap_get_state(), true))
+			opendous_tap_append_step(1, 0);
+		else {
+			LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition",
+					tap_state_name(tap_get_state()), tap_state_name(path[i]));
+			exit(-1);
+		}
+
+		tap_set_state(path[i]);
+	}
+
+	tap_set_end_state(tap_get_state());
+}
+
+void opendous_runtest(int num_cycles)
+{
+	int i;
+
+	tap_state_t saved_end_state = tap_get_end_state();
+
+	/* only do a state_move when we're not already in IDLE */
+	if (tap_get_state() != TAP_IDLE) {
+		opendous_end_state(TAP_IDLE);
+		opendous_state_move();
+	}
+
+	/* execute num_cycles */
+	for (i = 0; i < num_cycles; i++)
+		opendous_tap_append_step(0, 0);
+
+	/* finish in end_state */
+	opendous_end_state(saved_end_state);
+	if (tap_get_state() != tap_get_end_state())
+		opendous_state_move();
+}
+
+void opendous_scan(int ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command)
+{
+	tap_state_t saved_end_state;
+
+	opendous_tap_ensure_space(1, scan_size + 8);
+
+	saved_end_state = tap_get_end_state();
+
+	/* Move to appropriate scan state */
+	opendous_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
+
+	opendous_state_move();
+	opendous_end_state(saved_end_state);
+
+	/* Scan */
+	opendous_tap_append_scan(scan_size, buffer, command);
+
+	/* We are in Exit1, go to Pause */
+	opendous_tap_append_step(0, 0);
+
+	tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
+
+	if (tap_get_state() != tap_get_end_state())
+		opendous_state_move();
+}
+
+void opendous_reset(int trst, int srst)
+{
+	LOG_DEBUG("trst: %i, srst: %i", trst, srst);
+
+	/* Signals are active low */
+#if 0
+	if (srst == 0)
+		opendous_simple_command(JTAG_CMD_SET_SRST, 1);
+	else if (srst == 1)
+		opendous_simple_command(JTAG_CMD_SET_SRST, 0);
+
+	if (trst == 0)
+		opendous_simple_command(JTAG_CMD_SET_TRST, 1);
+	else if (trst == 1)
+		opendous_simple_command(JTAG_CMD_SET_TRST, 0);
+#endif
+
+	srst = srst ? 0 : 1;
+	trst = trst ? 0 : 2;
+	opendous_simple_command(JTAG_CMD_SET_SRST_TRST, srst | trst);
+}
+
+void opendous_simple_command(uint8_t command, uint8_t _data)
+{
+	int result;
+
+	DEBUG_JTAG_IO("0x%02x 0x%02x", command, _data);
+
+	usb_out_buffer[0] = (uint16_t) 2;
+	usb_out_buffer[2] = command;
+	usb_out_buffer[3] = _data;
+
+	result = opendous_usb_message(opendous_jtag_handle, 4, 1);
+	if (result != 1)
+		LOG_ERROR("opendous command 0x%02x failed (%d)", command, result);
+}
+
+int opendous_get_status(void)
+{
+	return ERROR_OK;
+}
+
+int opendous_get_version_info(void)
+{
+	return ERROR_OK;
+}
+
+/***************************************************************************/
+/* Estick tap functions */
+
+static int tap_length;
+static uint8_t tms_buffer[OPENDOUS_TAP_BUFFER_SIZE];
+static uint8_t tdo_buffer[OPENDOUS_TAP_BUFFER_SIZE];
+
+struct pending_scan_result {
+	int first;	/* First bit position in tdo_buffer to read */
+	int length; /* Number of bits to read */
+	struct scan_command *command; /* Corresponding scan command */
+	uint8_t *buffer;
+};
+
+static int pending_scan_results_length;
+static struct pending_scan_result pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
+
+static int last_tms;
+
+void opendous_tap_init(void)
+{
+	tap_length = 0;
+	pending_scan_results_length = 0;
+}
+
+void opendous_tap_ensure_space(int scans, int bits)
+{
+	int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
+
+	if (scans > available_scans)
+		opendous_tap_execute();
+}
+
+void opendous_tap_append_step(int tms, int tdi)
+{
+	last_tms = tms;
+	unsigned char _tms = tms ? 1 : 0;
+	unsigned char _tdi = tdi ? 1 : 0;
+
+	int tap_index =  tap_length / 4;
+	int bits  = (tap_length % 4) * 2;
+
+	if (tap_length < OPENDOUS_TAP_BUFFER_SIZE) {
+		if (!bits)
+			tms_buffer[tap_index] = 0;
+
+		tms_buffer[tap_index] |= (_tdi << bits)|(_tms << (bits + 1)) ;
+		tap_length++;
+	} else
+		LOG_ERROR("opendous_tap_append_step, overflow");
+}
+
+void opendous_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command)
+{
+	DEBUG_JTAG_IO("append scan, length = %d", length);
+
+	struct pending_scan_result *pending_scan_result = &pending_scan_results_buffer[pending_scan_results_length];
+	int i;
+
+	pending_scan_result->first = tap_length;
+	pending_scan_result->length = length;
+	pending_scan_result->command = command;
+	pending_scan_result->buffer = buffer;
+
+	for (i = 0; i < length; i++)
+		opendous_tap_append_step((i < length-1 ? 0 : 1), (buffer[i / 8] >> (i % 8)) & 1);
+	pending_scan_results_length++;
+}
+
+/* Pad and send a tap sequence to the device, and receive the answer.
+ * For the purpose of padding we assume that we are in idle or pause state. */
+int opendous_tap_execute(void)
+{
+	int byte_length, byte_length_out;
+	int i, j;
+	int result;
+	int output_counter;
+
+	if (tap_length > 0) {
+
+		/* memset(tdo_buffer,0,OPENDOUS_TAP_BUFFER_SIZE); */
+		/* LOG_INFO("OPENDOUS tap execute %d",tap_length); */
+		byte_length = (tap_length + 3) / 4;
+		byte_length_out = (tap_length + 7) / 8;
+
+#ifdef _DEBUG_USB_COMMS_
+		LOG_DEBUG("opendous is sending %d bytes", byte_length);
+#endif
+
+		output_counter = 0;
+		for (j = 0, i = 0; j <  byte_length;) {
+
+			int recieve;
+			int transmit = byte_length - j;
+			if (transmit > OPENDOUS_MAX_TAP_TRANSMIT) {
+				transmit = OPENDOUS_MAX_TAP_TRANSMIT;
+				recieve = (OPENDOUS_MAX_TAP_TRANSMIT) / 2;
+				usb_out_buffer[2] = JTAG_CMD_TAP_OUTPUT;
+			} else {
+				usb_out_buffer[2] = JTAG_CMD_TAP_OUTPUT | ((tap_length % 4) << 4);
+				recieve = (transmit + 1) / 2;
+			}
+			usb_out_buffer[0] = (transmit + 1) & 0xff;
+			usb_out_buffer[1] = ((transmit + 1) >> 8) & 0xff;
+
+			memmove(usb_out_buffer + 3, tms_buffer + j, transmit);
+			result = opendous_usb_message(opendous_jtag_handle, 3 + transmit, recieve);
+			if (result != recieve) {
+				LOG_ERROR("opendous_tap_execute, wrong result %d, expected %d", result, recieve);
+				return ERROR_JTAG_QUEUE_FAILED;
+			}
+
+			memmove(tdo_buffer + i, usb_in_buffer, recieve);
+			i += recieve;
+			j += transmit;
+		}
+
+		result = byte_length_out;
+#ifdef _DEBUG_USB_COMMS_
+		LOG_DEBUG("opendous tap result %d", result);
+		opendous_debug_buffer(tdo_buffer, result);
+#endif
+
+		/* LOG_INFO("eStick tap execute %d",tap_length); */
+		for (i = 0; i < pending_scan_results_length; i++) {
+
+			struct pending_scan_result *pending_scan_result = &pending_scan_results_buffer[i];
+			uint8_t *buffer = pending_scan_result->buffer;
+			int length = pending_scan_result->length;
+			int first = pending_scan_result->first;
+			struct scan_command *command = pending_scan_result->command;
+
+			/* Copy to buffer */
+			buf_set_buf(tdo_buffer, first, buffer, 0, length);
+
+			DEBUG_JTAG_IO("pending scan result, length = %d", length);
+
+#ifdef _DEBUG_USB_COMMS_
+			opendous_debug_buffer(buffer, byte_length_out);
+#endif
+
+			if (jtag_read_buffer(buffer, command) != ERROR_OK) {
+				opendous_tap_init();
+				return ERROR_JTAG_QUEUE_FAILED;
+			}
+
+			if (pending_scan_result->buffer != NULL)
+				free(pending_scan_result->buffer);
+		}
+
+		opendous_tap_init();
+	}
+
+	return ERROR_OK;
+}
+
+/*****************************************************************************/
+/* Estick USB low-level functions */
+
+struct opendous_jtag *opendous_usb_open(void)
+{
+	struct opendous_jtag *result;
+
+	struct jtag_libusb_device_handle *devh;
+	if (jtag_libusb_open(vids, pids, &devh) != ERROR_OK)
+		return NULL;
+
+	jtag_libusb_set_configuration(devh, 0);
+	jtag_libusb_claim_interface(devh, 0);
+
+	result = (struct opendous_jtag *) malloc(sizeof(struct opendous_jtag));
+	result->usb_handle = devh;
+	return result;
+}
+
+void opendous_usb_close(struct opendous_jtag *opendous_jtag)
+{
+	jtag_libusb_close(opendous_jtag->usb_handle);
+	free(opendous_jtag);
+}
+
+/* Send a message and receive the reply. */
+int opendous_usb_message(struct opendous_jtag *opendous_jtag, int out_length, int in_length)
+{
+	int result;
+
+	result = opendous_usb_write(opendous_jtag, out_length);
+	if (result == out_length) {
+		result = opendous_usb_read(opendous_jtag);
+		if (result == in_length)
+			return result;
+		else {
+			LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)", in_length, result);
+			return -1;
+		}
+	} else {
+		LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)", out_length, result);
+		return -1;
+	}
+}
+
+/* Write data from out_buffer to USB. */
+int opendous_usb_write(struct opendous_jtag *opendous_jtag, int out_length)
+{
+	int result;
+
+	if (out_length > OPENDOUS_OUT_BUFFER_SIZE) {
+		LOG_ERROR("opendous_jtag_write illegal out_length=%d (max=%d)", out_length, OPENDOUS_OUT_BUFFER_SIZE);
+		return -1;
+	}
+
+#ifdef _DEBUG_USB_COMMS_
+	LOG_DEBUG("%s: USB write begin", opendous_get_time(time_str));
+#endif
+	result = jtag_libusb_bulk_write(opendous_jtag->usb_handle, OPENDOUS_WRITE_ENDPOINT, \
+		(char *)usb_out_buffer, out_length, OPENDOUS_USB_TIMEOUT);
+#ifdef _DEBUG_USB_COMMS_
+	LOG_DEBUG("%s: USB write end: %d bytes", opendous_get_time(time_str), result);
+#endif
+
+	DEBUG_JTAG_IO("opendous_usb_write, out_length = %d, result = %d", out_length, result);
+
+#ifdef _DEBUG_USB_COMMS_
+	opendous_debug_buffer(usb_out_buffer, out_length);
+#endif
+	return result;
+}
+
+/* Read data from USB into in_buffer. */
+int opendous_usb_read(struct opendous_jtag *opendous_jtag)
+{
+#ifdef _DEBUG_USB_COMMS_
+	LOG_DEBUG("%s: USB read begin", opendous_get_time(time_str));
+#endif
+	int result = jtag_libusb_bulk_read(opendous_jtag->usb_handle, OPENDOUS_READ_ENDPOINT,
+		(char *)usb_in_buffer, OPENDOUS_IN_BUFFER_SIZE, OPENDOUS_USB_TIMEOUT);
+#ifdef _DEBUG_USB_COMMS_
+	LOG_DEBUG("%s: USB read end: %d bytes", opendous_get_time(time_str), result);
+#endif
+	DEBUG_JTAG_IO("opendous_usb_read, result = %d", result);
+
+#ifdef _DEBUG_USB_COMMS_
+	opendous_debug_buffer(usb_in_buffer, result);
+#endif
+	return result;
+}
+
+#ifdef _DEBUG_USB_COMMS_
+#define BYTES_PER_LINE  16
+
+void opendous_debug_buffer(uint8_t *buffer, int length)
+{
+	char line[81];
+	char s[4];
+	int i;
+	int j;
+
+	for (i = 0; i < length; i += BYTES_PER_LINE) {
+		snprintf(line, 5, "%04x", i);
+		for (j = i; j < i + BYTES_PER_LINE && j < length; j++) {
+			snprintf(s, 4, " %02x", buffer[j]);
+			strcat(line, s);
+		}
+		LOG_DEBUG("%s", line);
+	}
+}
+
+char *opendous_get_time(char *str)
+{
+	struct timeb timebuffer;
+	char *timeline;
+
+	ftime(&timebuffer);
+	timeline = ctime(&(timebuffer.time));
+	snprintf(str, 49, "%.8s.%hu", &timeline[11], timebuffer.millitm);
+	return str;
+}
+#endif
diff --git a/src/jtag/interfaces.c b/src/jtag/interfaces.c
index 4937adb..88bf929 100644
--- a/src/jtag/interfaces.c
+++ b/src/jtag/interfaces.c
@@ -107,6 +107,9 @@ extern struct jtag_interface stlink_interface;
 #if BUILD_OSBDM == 1
 extern struct jtag_interface osbdm_interface;
 #endif
+#if BUILD_OPENDOUS == 1
+extern struct jtag_interface opendous_interface;
+#endif
 #endif /* standard drivers */
 
 /**
@@ -182,6 +185,9 @@ struct jtag_interface *jtag_interfaces[] = {
 #if BUILD_OSBDM == 1
 		&osbdm_interface,
 #endif
+#if BUILD_OPENDOUS == 1
+		&opendous_interface,
+#endif
 #endif /* standard drivers */
 		NULL,
 	};
diff --git a/tcl/interface/estick.cfg b/tcl/interface/estick.cfg
new file mode 100644
index 0000000..adefcb7
--- /dev/null
+++ b/tcl/interface/estick.cfg
@@ -0,0 +1,7 @@
+#
+# eStick
+#
+# http://code.google.com/p/estick-jtag/
+#
+
+interface opendous
diff --git a/tcl/interface/opendous.cfg b/tcl/interface/opendous.cfg
new file mode 100644
index 0000000..21ced6f
--- /dev/null
+++ b/tcl/interface/opendous.cfg
@@ -0,0 +1,7 @@
+#
+# opendous-jtag
+#
+# http://code.google.com/p/opendous-jtag/
+#
+
+interface opendous