X-Git-Url: https://review.openocd.org/gitweb?p=openocd.git;a=blobdiff_plain;f=src%2Fjtag%2Fdrivers%2Fvsllink.c;h=4907ef0e2efd7e08ec1c064385d89fb78b3be31f;hp=451d5f8f05328c46d07421788e223411a5c95cb0;hb=HEAD;hpb=db464f3cd4ed83b9f3411a98362dd67aad7bc3fd

diff --git a/src/jtag/drivers/vsllink.c b/src/jtag/drivers/vsllink.c
index 451d5f8f05..34525d5468 100644
--- a/src/jtag/drivers/vsllink.c
+++ b/src/jtag/drivers/vsllink.c
@@ -1,242 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
 /***************************************************************************
  *   Copyright (C) 2009-2010 by Simon Qian <SimonQian@SimonQian.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 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.             *
  ***************************************************************************/
 
 /* Versaloon is a programming tool for multiple MCUs.
  * It's distributed under GPLv3.
- * You can find it at http://www.SimonQian.com/en/Versaloon.
+ * You can find it at http://www.Versaloon.com/.
  */
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
+#include <jtag/adapter.h>
 #include <jtag/interface.h>
 #include <jtag/commands.h>
-#include "usb_common.h"
-
-//#define _VSLLINK_IN_DEBUG_MODE_
-
-static uint16_t vsllink_usb_vid;
-static uint16_t vsllink_usb_pid;
-static uint8_t  vsllink_usb_bulkout;
-static uint8_t  vsllink_usb_bulkin;
-static uint8_t  vsllink_usb_interface;
-static int      VSLLINK_USB_TIMEOUT = 1000;
-
-static int vsllink_tms_offset = 0;
-
-/* Global USB buffers */
-static uint8_t* vsllink_usb_in_buffer  = NULL;
-static uint8_t* vsllink_usb_out_buffer = NULL;
-static int      vsllink_buffer_size    = 128;
-
-/* Constants for Versaloon command */
-#define VERSALOON_GET_INFO				0x00
-#define VERSALOON_GET_TVCC				0x01
-
-/* Constants for VSLLink command */
-#define VSLLINK_CMD_CONN				0x80
-#define VSLLINK_CMD_DISCONN				0x81
-#define VSLLINK_CMD_SET_SPEED			0x82
-#define VSLLINK_CMD_SET_PORT			0x90
-#define VSLLINK_CMD_GET_PORT			0x91
-#define VSLLINK_CMD_SET_PORTDIR			0x92
-#define VSLLINK_CMD_HW_JTAGSEQCMD		0xA0
-#define VSLLINK_CMD_HW_JTAGHLCMD		0xA1
-#define VSLLINK_CMD_HW_SWDCMD			0xA2
-#define VSLLINK_CMD_HW_JTAGRAWCMD		0xA3
-
-#define VSLLINK_CMDJTAGSEQ_TMSBYTE		0x00
-#define VSLLINK_CMDJTAGSEQ_TMSCLOCK		0x40
-#define VSLLINK_CMDJTAGSEQ_SCAN			0x80
-
-#define VSLLINK_CMDJTAGSEQ_CMDMSK		0xC0
-#define VSLLINK_CMDJTAGSEQ_LENMSK		0x3F
-
-#define JTAG_PINMSK_SRST				(1 << 0)
-#define JTAG_PINMSK_TRST				(1 << 1)
-#define JTAG_PINMSK_USR1				(1 << 2)
-#define JTAG_PINMSK_USR2				(1 << 3)
-#define JTAG_PINMSK_TCK					(1 << 4)
-#define JTAG_PINMSK_TMS					(1 << 5)
-#define JTAG_PINMSK_TDI					(1 << 6)
-#define JTAG_PINMSK_TDO					(1 << 7)
+#include <jtag/swd.h>
+#include <libusb.h>
+
+#include "versaloon/versaloon_include.h"
+#include "versaloon/versaloon.h"
+
+static int vsllink_tms_offset;
 
 struct pending_scan_result {
 	int src_offset;
 	int dest_offset;
-	int length; /* Number of bits to read */
-	struct scan_command *command; /* Corresponding scan command */
+	int length;	/* Number of bits to read */
+	struct scan_command *command;	/* Corresponding scan command */
+	uint8_t *ack;
 	uint8_t *buffer;
-	bool last; /* indicate the last scan pending */
+	bool last;	/* indicate the last scan pending */
 };
 
 #define MAX_PENDING_SCAN_RESULTS 256
 
 static int pending_scan_results_length;
-static struct pending_scan_result \
-						pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
+static struct pending_scan_result
+	pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 
 /* Queue command functions */
 static void vsllink_end_state(tap_state_t state);
 static void vsllink_state_move(void);
 static void vsllink_path_move(int num_states, tap_state_t *path);
+static void vsllink_tms(int num_bits, const uint8_t *bits);
 static void vsllink_runtest(int num_cycles);
 static void vsllink_stableclocks(int num_cycles, int tms);
-static void vsllink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, \
-							int scan_size, struct scan_command *command);
-static void vsllink_reset(int trst, int srst);
-static void vsllink_simple_command(uint8_t command);
+static void vsllink_scan(bool ir_scan, enum scan_type type,
+		uint8_t *buffer, int scan_size, struct scan_command *command);
+static int vsllink_reset(int trst, int srst);
 
 /* VSLLink tap buffer functions */
 static void vsllink_tap_append_step(int tms, int tdi);
 static void vsllink_tap_init(void);
 static int  vsllink_tap_execute(void);
 static void vsllink_tap_ensure_pending(int scans);
-static void vsllink_tap_append_scan(int length, uint8_t *buffer, \
-									struct scan_command *command);
+static void vsllink_tap_append_scan(int length, uint8_t *buffer,
+		struct scan_command *command);
+
+/* VSLLink SWD functions */
+static int_least32_t vsllink_swd_frequency(int_least32_t hz);
+static int vsllink_swd_switch_seq(enum swd_special_seq seq);
 
 /* VSLLink lowlevel functions */
 struct vsllink {
-	struct usb_dev_handle* usb_handle;
+	struct libusb_context *libusb_ctx;
+	struct libusb_device_handle *usb_device_handle;
 };
 
-static struct vsllink *vsllink_usb_open(void);
+static int vsllink_usb_open(struct vsllink *vsllink);
 static void vsllink_usb_close(struct vsllink *vsllink);
-static int vsllink_usb_message(struct vsllink *vsllink, int out_length, \
-								int in_length);
-static int vsllink_usb_write(struct vsllink *vsllink, int out_length);
-static int vsllink_usb_read(struct vsllink *vsllink);
 
-#if defined _DEBUG_USB_COMMS_ || defined _DEBUG_JTAG_IO_
 static void vsllink_debug_buffer(uint8_t *buffer, int length);
-#endif
 
-static int tap_length = 0;
-static int tap_buffer_size = 0;
-static uint8_t *tms_buffer = NULL;
-static uint8_t *tdi_buffer = NULL;
-static uint8_t *tdo_buffer = NULL;
+static int tap_length;
+static int tap_buffer_size;
+static uint8_t *tms_buffer;
+static uint8_t *tdi_buffer;
+static uint8_t *tdo_buffer;
 
-static struct vsllink* vsllink_handle = NULL;
+static bool swd_mode;
 
-static void reset_command_pointer(void)
-{
-	tap_length = 0;
-}
+static struct vsllink *vsllink_handle;
 
-static int vsllink_execute_queue(void)
+static int vsllink_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
 
-	DEBUG_JTAG_IO(	"-------------------------------------"
-					" vsllink "
-					"-------------------------------------");
+	LOG_DEBUG_IO("-------------------------------------"
+		" vsllink "
+		"-------------------------------------");
 
-	reset_command_pointer();
-	while (cmd != NULL)
-	{
-		switch (cmd->type)
-		{
+	while (cmd) {
+		switch (cmd->type) {
 			case JTAG_RUNTEST:
-				DEBUG_JTAG_IO("runtest %i cycles, end in %s", \
-								cmd->cmd.runtest->num_cycles, \
-								tap_state_name(cmd->cmd.runtest->end_state));
+				LOG_DEBUG_IO("runtest %i cycles, end in %s",
+						cmd->cmd.runtest->num_cycles,
+						tap_state_name(cmd->cmd.runtest->end_state));
 
 				vsllink_end_state(cmd->cmd.runtest->end_state);
 				vsllink_runtest(cmd->cmd.runtest->num_cycles);
 				break;
 
-			case JTAG_STATEMOVE:
-				DEBUG_JTAG_IO("statemove end in %s", \
-								tap_state_name(cmd->cmd.statemove->end_state));
+			case JTAG_TLR_RESET:
+				LOG_DEBUG_IO("statemove end in %s",
+						tap_state_name(cmd->cmd.statemove->end_state));
 
 				vsllink_end_state(cmd->cmd.statemove->end_state);
 				vsllink_state_move();
 				break;
 
 			case JTAG_PATHMOVE:
-				DEBUG_JTAG_IO("pathmove: %i states, end in %s", \
-					cmd->cmd.pathmove->num_states, \
-					tap_state_name(cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]));
+				LOG_DEBUG_IO("pathmove: %i states, end in %s",
+						cmd->cmd.pathmove->num_states,
+						tap_state_name(cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]));
 
-				vsllink_path_move(cmd->cmd.pathmove->num_states, \
-									cmd->cmd.pathmove->path);
+				vsllink_path_move(cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path);
 				break;
 
 			case JTAG_SCAN:
+				LOG_DEBUG_IO("JTAG Scan...");
+
 				vsllink_end_state(cmd->cmd.scan->end_state);
 
-				scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
+				scan_size = jtag_build_buffer(
+						cmd->cmd.scan, &buffer);
+
 				if (cmd->cmd.scan->ir_scan)
-				{
-					DEBUG_JTAG_IO("JTAG Scan write IR(%d bits), end in %s:", \
-									scan_size, \
-									tap_state_name(cmd->cmd.scan->end_state));
-				}
+					LOG_DEBUG_IO(
+							"JTAG Scan write IR(%d bits), "
+							"end in %s:",
+							scan_size,
+							tap_state_name(cmd->cmd.scan->end_state));
+
 				else
-				{
-					DEBUG_JTAG_IO("JTAG Scan write DR(%d bits), end in %s:", \
-									scan_size, \
-									tap_state_name(cmd->cmd.scan->end_state));
-				}
+					LOG_DEBUG_IO(
+							"JTAG Scan write DR(%d bits), "
+							"end in %s:",
+							scan_size,
+							tap_state_name(cmd->cmd.scan->end_state));
 
-#ifdef _DEBUG_JTAG_IO_
-				vsllink_debug_buffer(buffer, DIV_ROUND_UP(scan_size, 8));
-#endif
+				if (LOG_LEVEL_IS(LOG_LVL_DEBUG_IO))
+					vsllink_debug_buffer(buffer, DIV_ROUND_UP(scan_size, 8));
 
 				type = jtag_scan_type(cmd->cmd.scan);
 
-				vsllink_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);
-
-				vsllink_tap_execute();
-
-				if (cmd->cmd.reset->trst == 1)
-				{
-					tap_set_state(TAP_RESET);
-				}
-				vsllink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
+				vsllink_scan(cmd->cmd.scan->ir_scan,
+						type, buffer, scan_size,
+						cmd->cmd.scan);
 				break;
 
 			case JTAG_SLEEP:
-				DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
+				LOG_DEBUG_IO("sleep %" PRIu32, cmd->cmd.sleep->us);
 				vsllink_tap_execute();
 				jtag_sleep(cmd->cmd.sleep->us);
 				break;
 
 			case JTAG_STABLECLOCKS:
-				DEBUG_JTAG_IO("add %d clocks", \
-								cmd->cmd.stableclocks->num_cycles);
-				switch (tap_get_state())
-				{
+				LOG_DEBUG_IO("add %d clocks",
+						cmd->cmd.stableclocks->num_cycles);
+
+				switch (tap_get_state()) {
 				case TAP_RESET:
-					// tms should be '1' to stay in TAP_RESET mode
+					/* tms must be '1' to stay
+					 * n TAP_RESET mode
+					 */
 					scan_size = 1;
 					break;
 				case TAP_DRSHIFT:
@@ -244,22 +176,31 @@ static int vsllink_execute_queue(void)
 				case TAP_DRPAUSE:
 				case TAP_IRSHIFT:
 				case TAP_IRPAUSE:
-					// in other mode, tms should be '0'
+					/* else, tms should be '0' */
 					scan_size = 0;
-					break;			/* above stable states are OK */
+					break;
+				/* above stable states are OK */
 				default:
-					 LOG_ERROR("jtag_add_clocks() in non-stable state \"%s\"",
-								tap_state_name(tap_get_state()));
-					 exit(-1);
+					LOG_ERROR("jtag_add_clocks() "
+							"in non-stable state \"%s\"",
+							tap_state_name(tap_get_state())
+					);
+					exit(-1);
 				}
-				vsllink_stableclocks(cmd->cmd.stableclocks->num_cycles, \
-										scan_size);
+				vsllink_stableclocks(cmd->cmd.stableclocks->num_cycles, scan_size);
 				break;
 
-			default:
-				LOG_ERROR("BUG: unknown JTAG command type encountered: %d", \
-							cmd->type);
-				exit(-1);
+				case JTAG_TMS:
+					LOG_DEBUG_IO("add %d jtag tms",
+							cmd->cmd.tms->num_bits);
+
+					vsllink_tms(cmd->cmd.tms->num_bits, cmd->cmd.tms->bits);
+					break;
+
+				default:
+					LOG_ERROR("BUG: unknown JTAG command type "
+							"encountered: %d", cmd->type);
+					exit(-1);
 		}
 		cmd = cmd->next;
 	}
@@ -269,25 +210,13 @@ static int vsllink_execute_queue(void)
 
 static int vsllink_speed(int speed)
 {
-	int result;
-
-	vsllink_usb_out_buffer[0] = VSLLINK_CMD_SET_SPEED;
-	vsllink_usb_out_buffer[1] = (speed >> 0) & 0xff;
-	vsllink_usb_out_buffer[2] = (speed >> 8) & 0xFF;
-
-	result = vsllink_usb_write(vsllink_handle, 3);
-
-	if (result == 3)
-	{
+	if (swd_mode) {
+		vsllink_swd_frequency(speed * 1000);
 		return ERROR_OK;
 	}
-	else
-	{
-		LOG_ERROR("VSLLink setting speed failed (%d)", result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
 
-	return ERROR_OK;
+	versaloon_interface.adaptors.jtag_raw.config(0, (uint16_t)speed);
+	return versaloon_interface.adaptors.peripheral_commit();
 }
 
 static int vsllink_khz(int khz, int *jtag_speed)
@@ -304,182 +233,124 @@ static int vsllink_speed_div(int jtag_speed, int *khz)
 	return ERROR_OK;
 }
 
-static int vsllink_init(void)
+static void vsllink_free_buffer(void)
 {
-	int check_cnt, to_tmp;
-	int result;
-	char version_str[100];
+	free(tdi_buffer);
+	tdi_buffer = NULL;
 
-	vsllink_usb_in_buffer = malloc(vsllink_buffer_size);
-	vsllink_usb_out_buffer = malloc(vsllink_buffer_size);
-	if ((vsllink_usb_in_buffer == NULL) || (vsllink_usb_out_buffer == NULL))
-	{
-		LOG_ERROR("Not enough memory");
-		exit(-1);
-	}
+	free(tdo_buffer);
+	tdo_buffer = NULL;
 
-	vsllink_handle = vsllink_usb_open();
-	if (vsllink_handle == 0)
-	{
-		LOG_ERROR("Can't find USB JTAG Interface!"\
-					"Please check connection and permissions.");
-		return ERROR_JTAG_INIT_FAILED;
-	}
-	LOG_DEBUG("vsllink found on %04X:%04X", vsllink_usb_vid, vsllink_usb_pid);
+	free(tms_buffer);
+	tms_buffer = NULL;
+}
 
-	to_tmp = VSLLINK_USB_TIMEOUT;
-	VSLLINK_USB_TIMEOUT = 100;
-	check_cnt = 0;
-	while (check_cnt < 5)
-	{
-		vsllink_simple_command(VERSALOON_GET_INFO);
-		result = vsllink_usb_read(vsllink_handle);
-
-		if (result > 2)
-		{
-			vsllink_usb_in_buffer[result] = 0;
-			vsllink_buffer_size = vsllink_usb_in_buffer[0] + \
-									(vsllink_usb_in_buffer[1] << 8);
-			strncpy(version_str, (char *)vsllink_usb_in_buffer + 2, \
-					sizeof(version_str));
-			LOG_INFO("%s", version_str);
-
-			// free the pre-alloc memroy
-			free(vsllink_usb_in_buffer);
-			free(vsllink_usb_out_buffer);
-			vsllink_usb_in_buffer = NULL;
-			vsllink_usb_out_buffer = NULL;
-
-			// alloc new memory
-			vsllink_usb_in_buffer = malloc(vsllink_buffer_size);
-			vsllink_usb_out_buffer = malloc(vsllink_buffer_size);
-			if ((vsllink_usb_in_buffer == NULL) || \
-				(vsllink_usb_out_buffer == NULL))
-			{
-				LOG_ERROR("Not enough memory");
-				exit(-1);
-			}
-			else
-			{
-				LOG_INFO("buffer size for USB is %d bytes", \
-							vsllink_buffer_size);
-			}
-			// alloc tms/tdi/tdo buffer
-			tap_buffer_size = (vsllink_buffer_size - 3) / 2;
-			tms_buffer = (uint8_t*)malloc(tap_buffer_size);
-			tdi_buffer = (uint8_t*)malloc(tap_buffer_size);
-			tdo_buffer = (uint8_t*)malloc(tap_buffer_size);
-			if ((tms_buffer == NULL) || (tdi_buffer == NULL) || \
-				(tdo_buffer == NULL))
-			{
-				LOG_ERROR("Not enough memory");
-				exit(-1);
-			}
-			break;
-		}
-		vsllink_simple_command(VSLLINK_CMD_DISCONN);
-		check_cnt++;
-	}
-	if (check_cnt == 3)
-	{
-		// Fail to access Versaloon
-		LOG_ERROR("VSLLink initial failed");
-		exit(-1);
-	}
-	VSLLINK_USB_TIMEOUT = to_tmp;
-
-	/* Some older firmware versions sometimes fail if the
-	 * voltage isn't read first.
-	 */
-	vsllink_simple_command(VERSALOON_GET_TVCC);
-	result = vsllink_usb_read(vsllink_handle);
-	if (result != 2)
-	{
-		LOG_WARNING("Fail to get target voltage");
-	}
+static int vsllink_quit(void)
+{
+	versaloon_interface.adaptors.gpio.config(0, GPIO_SRST | GPIO_TRST,
+		0, 0, GPIO_SRST | GPIO_TRST);
+	versaloon_interface.adaptors.gpio.fini(0);
+
+	if (swd_mode)
+		versaloon_interface.adaptors.swd.fini(0);
 	else
-	{
-		LOG_INFO("Target runs at %d mV", vsllink_usb_in_buffer[0] + \
-					(vsllink_usb_in_buffer[1] << 8));
-	}
+		versaloon_interface.adaptors.jtag_raw.fini(0);
 
-	// connect to vsllink
-	vsllink_usb_out_buffer[0] = VSLLINK_CMD_CONN;
-	vsllink_usb_out_buffer[1] = 1;
-	vsllink_usb_message(vsllink_handle, 2, 0);
-	if (vsllink_usb_read(vsllink_handle) > 2)
-	{
-		strncpy(version_str, (char *)vsllink_usb_in_buffer + 2, \
-				sizeof(version_str));
-		LOG_INFO("%s", version_str);
-	}
+	versaloon_interface.adaptors.peripheral_commit();
+	versaloon_interface.fini();
 
-	// Set SRST and TRST to output, Set USR1 and USR2 to input
-	vsllink_usb_out_buffer[0] = VSLLINK_CMD_SET_PORTDIR;
-	vsllink_usb_out_buffer[1] = JTAG_PINMSK_SRST | JTAG_PINMSK_TRST | \
-								JTAG_PINMSK_USR1 | JTAG_PINMSK_USR2;
-	vsllink_usb_out_buffer[2] = JTAG_PINMSK_SRST | JTAG_PINMSK_TRST;
-	if (vsllink_usb_write(vsllink_handle, 3) != 3)
-	{
-		LOG_ERROR("VSLLink USB send data error");
-		exit(-1);
+	vsllink_free_buffer();
+	vsllink_usb_close(vsllink_handle);
+
+	libusb_exit(vsllink_handle->libusb_ctx);
+	free(vsllink_handle);
+
+	return ERROR_OK;
+}
+
+static int vsllink_interface_init(void)
+{
+	vsllink_handle = malloc(sizeof(struct vsllink));
+	if (!vsllink_handle) {
+		LOG_ERROR("unable to allocate memory");
+		return ERROR_FAIL;
 	}
 
-	vsllink_reset(0, 0);
+	libusb_init(&vsllink_handle->libusb_ctx);
 
-	LOG_INFO("VSLLink Interface ready");
+	if (vsllink_usb_open(vsllink_handle) != ERROR_OK) {
+		LOG_ERROR("Can't find USB JTAG Interface!"
+			"Please check connection and permissions.");
+		return ERROR_JTAG_INIT_FAILED;
+	}
+	LOG_DEBUG("vsllink found on %04X:%04X",
+		versaloon_interface.usb_setting.vid,
+		versaloon_interface.usb_setting.pid);
+	versaloon_usb_device_handle = vsllink_handle->usb_device_handle;
 
-	vsllink_tap_init();
+	if (versaloon_interface.init() != ERROR_OK)
+		return ERROR_FAIL;
+	if (versaloon_interface.usb_setting.buf_size < 32) {
+		versaloon_interface.fini();
+		return ERROR_FAIL;
+	}
 
 	return ERROR_OK;
 }
 
-static int vsllink_quit(void)
+static int vsllink_init(void)
 {
-	if ((vsllink_usb_in_buffer != NULL) && (vsllink_usb_out_buffer != NULL))
-	{
-		// Set all pins to input
-		vsllink_usb_out_buffer[0] = VSLLINK_CMD_SET_PORTDIR;
-		vsllink_usb_out_buffer[1] = JTAG_PINMSK_SRST | JTAG_PINMSK_TRST | \
-									JTAG_PINMSK_USR1 | JTAG_PINMSK_USR2;
-		vsllink_usb_out_buffer[2] = 0;
-		if (vsllink_usb_write(vsllink_handle, 3) != 3)
-		{
-			LOG_ERROR("VSLLink USB send data error");
-			exit(-1);
+	int retval = vsllink_interface_init();
+	if (retval != ERROR_OK)
+		return retval;
+
+	versaloon_interface.adaptors.gpio.init(0);
+	versaloon_interface.adaptors.gpio.config(0, GPIO_SRST, 0, GPIO_SRST,
+		GPIO_SRST);
+	versaloon_interface.adaptors.delay.delayms(100);
+	versaloon_interface.adaptors.peripheral_commit();
+
+	if (swd_mode) {
+		versaloon_interface.adaptors.gpio.config(0, GPIO_TRST, 0,
+			GPIO_TRST, GPIO_TRST);
+		versaloon_interface.adaptors.swd.init(0);
+		vsllink_swd_frequency(adapter_get_speed_khz() * 1000);
+		vsllink_swd_switch_seq(JTAG_TO_SWD);
+
+	} else {
+		/* malloc buffer size for tap */
+		tap_buffer_size = versaloon_interface.usb_setting.buf_size / 2 - 32;
+		vsllink_free_buffer();
+		tdi_buffer = malloc(tap_buffer_size);
+		tdo_buffer = malloc(tap_buffer_size);
+		tms_buffer = malloc(tap_buffer_size);
+		if ((!tdi_buffer) || (!tdo_buffer) || (!tms_buffer)) {
+			vsllink_quit();
+			return ERROR_FAIL;
 		}
 
-		// disconnect
-		vsllink_simple_command(VSLLINK_CMD_DISCONN);
-		vsllink_usb_close(vsllink_handle);
-		vsllink_handle = NULL;
+		versaloon_interface.adaptors.jtag_raw.init(0);
+		versaloon_interface.adaptors.jtag_raw.config(0, adapter_get_speed_khz());
+		versaloon_interface.adaptors.gpio.config(0, GPIO_SRST | GPIO_TRST,
+			GPIO_TRST, GPIO_SRST, GPIO_SRST);
 	}
 
-	if (vsllink_usb_in_buffer != NULL)
-	{
-		free(vsllink_usb_in_buffer);
-		vsllink_usb_in_buffer = NULL;
-	}
-	if (vsllink_usb_out_buffer != NULL)
-	{
-		free(vsllink_usb_out_buffer);
-		vsllink_usb_out_buffer = NULL;
-	}
+	if (versaloon_interface.adaptors.peripheral_commit() != ERROR_OK)
+		return ERROR_FAIL;
 
+	vsllink_reset(0, 0);
+	vsllink_tap_init();
 	return ERROR_OK;
 }
 
-/***************************************************************************/
-/* Queue command implementations */
+/**************************************************************************
+ * Queue command implementations */
 
 static void vsllink_end_state(tap_state_t state)
 {
 	if (tap_is_state_stable(state))
-	{
 		tap_set_end_state(state);
-	}
-	else
-	{
+	else {
 		LOG_ERROR("BUG: %i is not a valid end state", state);
 		exit(-1);
 	}
@@ -489,35 +360,28 @@ static void vsllink_end_state(tap_state_t state)
 static void vsllink_state_move(void)
 {
 	int i;
-	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());
+	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++)
-	{
 		vsllink_tap_append_step((tms_scan >> i) & 1, 0);
-	}
 
 	tap_set_state(tap_get_end_state());
 }
 
 static void vsllink_path_move(int num_states, tap_state_t *path)
 {
-	for (int i = 0; i < num_states; i++)
-	{
+	for (int i = 0; i < num_states; i++) {
 		if (path[i] == tap_state_transition(tap_get_state(), false))
-		{
 			vsllink_tap_append_step(0, 0);
-		}
 		else if (path[i] == tap_state_transition(tap_get_state(), true))
-		{
 			vsllink_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]));
+		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);
 		}
 
@@ -527,10 +391,15 @@ static void vsllink_path_move(int num_states, tap_state_t *path)
 	tap_set_end_state(tap_get_state());
 }
 
+static void vsllink_tms(int num_bits, const uint8_t *bits)
+{
+	for (int i = 0; i < num_bits; i++)
+		vsllink_tap_append_step((bits[i / 8] >> (i % 8)) & 1, 0);
+}
+
 static void vsllink_stableclocks(int num_cycles, int tms)
 {
-	while (num_cycles > 0)
-	{
+	while (num_cycles > 0) {
 		vsllink_tap_append_step(tms, 0);
 		num_cycles--;
 	}
@@ -540,26 +409,23 @@ static void vsllink_runtest(int num_cycles)
 {
 	tap_state_t saved_end_state = tap_get_end_state();
 
-	if (tap_get_state() != TAP_IDLE)
-	{
-		// enter into IDLE state
+	if (tap_get_state() != TAP_IDLE) {
+		/* enter IDLE state */
 		vsllink_end_state(TAP_IDLE);
 		vsllink_state_move();
 	}
 
 	vsllink_stableclocks(num_cycles, 0);
 
-	// post-process
-	// set end_state
+	/* post-process */
+	/* set end_state */
 	vsllink_end_state(saved_end_state);
 	if (tap_get_end_state() != tap_get_end_state())
-	{
 		vsllink_state_move();
-	}
 }
 
-static void vsllink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, \
-							int scan_size, struct scan_command *command)
+static void vsllink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer,
+	int scan_size, struct scan_command *command)
 {
 	tap_state_t saved_end_state;
 
@@ -569,9 +435,7 @@ static void vsllink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, \
 	vsllink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
 
 	if (tap_get_state() != tap_get_end_state())
-	{
 		vsllink_state_move();
-	}
 	vsllink_end_state(saved_end_state);
 
 	/* Scan */
@@ -584,100 +448,56 @@ static void vsllink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, \
 	tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
 
 	if (tap_get_state() != tap_get_end_state())
-	{
 		vsllink_state_move();
-	}
 }
 
-static void vsllink_reset(int trst, int srst)
+static int vsllink_reset(int trst, int srst)
 {
-	int result;
-
 	LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 
-	/* Signals are active low */
-	vsllink_usb_out_buffer[0] = VSLLINK_CMD_SET_PORT;
-	vsllink_usb_out_buffer[1] = JTAG_PINMSK_SRST | JTAG_PINMSK_TRST;
-	vsllink_usb_out_buffer[2] = 0;
-	if (srst == 0)
-	{
-		vsllink_usb_out_buffer[2] |= JTAG_PINMSK_SRST;
-	}
-	if (trst == 0)
-	{
-		vsllink_usb_out_buffer[2] |= JTAG_PINMSK_TRST;
-	}
-
-	result = vsllink_usb_write(vsllink_handle, 3);
-	if (result != 3)
-	{
-		LOG_ERROR("VSLLink command VSLLINK_CMD_SET_PORT failed (%d)", result);
-	}
-}
-
-static void vsllink_simple_command(uint8_t command)
-{
-	int result;
-
-	DEBUG_JTAG_IO("0x%02x", command);
-
-	vsllink_usb_out_buffer[0] = command;
-	result = vsllink_usb_write(vsllink_handle, 1);
-
-	if (result != 1)
-	{
-		LOG_ERROR("VSLLink command 0x%02x failed (%d)", command, result);
-	}
-}
+	if (!srst)
+		versaloon_interface.adaptors.gpio.config(0, GPIO_SRST, 0, GPIO_SRST, GPIO_SRST);
+	else
+		versaloon_interface.adaptors.gpio.config(0, GPIO_SRST, GPIO_SRST, 0, 0);
 
-COMMAND_HANDLER(vsllink_handle_mode_command)
-{
-	if (CMD_ARGC != 1) {
-		LOG_ERROR("parameter error, "
-					"should be one parameter for mode");
-		return ERROR_FAIL;
+	if (!swd_mode) {
+		if (!trst)
+			versaloon_interface.adaptors.gpio.out(0, GPIO_TRST, GPIO_TRST);
+		else
+			versaloon_interface.adaptors.gpio.out(0, GPIO_TRST, 0);
 	}
 
-	return ERROR_OK;
+	return versaloon_interface.adaptors.peripheral_commit();
 }
 
 COMMAND_HANDLER(vsllink_handle_usb_vid_command)
 {
 	if (CMD_ARGC != 1)
-	{
-		LOG_ERROR("parameter error, "
-					"should be one parameter for VID");
-		return ERROR_OK;
-	}
+		return ERROR_COMMAND_SYNTAX_ERROR;
 
-	COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], vsllink_usb_vid);
+	COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0],
+		versaloon_interface.usb_setting.vid);
 	return ERROR_OK;
 }
 
 COMMAND_HANDLER(vsllink_handle_usb_pid_command)
 {
 	if (CMD_ARGC != 1)
-	{
-		LOG_ERROR("parameter error, "
-					"should be one parameter for PID");
-		return ERROR_OK;
-	}
-	COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], vsllink_usb_pid);
+		return ERROR_COMMAND_SYNTAX_ERROR;
+	COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0],
+		versaloon_interface.usb_setting.pid);
 	return ERROR_OK;
 }
 
 COMMAND_HANDLER(vsllink_handle_usb_bulkin_command)
 {
 	if (CMD_ARGC != 1)
-	{
-		LOG_ERROR("parameter error, "
-					"should be one parameter for BULKIN endpoint");
-		return ERROR_OK;
-	}
+		return ERROR_COMMAND_SYNTAX_ERROR;
 
-	COMMAND_PARSE_NUMBER(u8, CMD_ARGV[0], vsllink_usb_bulkin);
+	COMMAND_PARSE_NUMBER(u8, CMD_ARGV[0],
+		versaloon_interface.usb_setting.ep_in);
 
-	vsllink_usb_bulkin |= 0x80;
+	versaloon_interface.usb_setting.ep_in |= 0x80;
 
 	return ERROR_OK;
 }
@@ -685,15 +505,12 @@ COMMAND_HANDLER(vsllink_handle_usb_bulkin_command)
 COMMAND_HANDLER(vsllink_handle_usb_bulkout_command)
 {
 	if (CMD_ARGC != 1)
-	{
-		LOG_ERROR("parameter error, "
-					"should be one parameter for BULKOUT endpoint");
-		return ERROR_OK;
-	}
+		return ERROR_COMMAND_SYNTAX_ERROR;
 
-	COMMAND_PARSE_NUMBER(u8, CMD_ARGV[0], vsllink_usb_bulkout);
+	COMMAND_PARSE_NUMBER(u8, CMD_ARGV[0],
+		versaloon_interface.usb_setting.ep_out);
 
-	vsllink_usb_bulkout &= ~0x80;
+	versaloon_interface.usb_setting.ep_out &= ~0x80;
 
 	return ERROR_OK;
 }
@@ -701,18 +518,15 @@ COMMAND_HANDLER(vsllink_handle_usb_bulkout_command)
 COMMAND_HANDLER(vsllink_handle_usb_interface_command)
 {
 	if (CMD_ARGC != 1)
-	{
-		LOG_ERROR("parameter error, "
-					"should be one parameter for interface number");
-		return ERROR_OK;
-	}
+		return ERROR_COMMAND_SYNTAX_ERROR;
 
-	COMMAND_PARSE_NUMBER(u8, CMD_ARGV[0], vsllink_usb_interface);
+	COMMAND_PARSE_NUMBER(u8, CMD_ARGV[0],
+		versaloon_interface.usb_setting.interface);
 	return ERROR_OK;
 }
 
-/***************************************************************************/
-/* VSLLink tap functions */
+/**************************************************************************
+ * VSLLink tap functions */
 
 static void vsllink_tap_init(void)
 {
@@ -723,69 +537,55 @@ static void vsllink_tap_init(void)
 
 static void vsllink_tap_ensure_pending(int scans)
 {
-	int available_scans = \
-			MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
+	int available_scans =
+		MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 
 	if (scans > available_scans)
-	{
 		vsllink_tap_execute();
-	}
 }
 
 static void vsllink_tap_append_step(int tms, int tdi)
 {
-	int index = tap_length / 8;
+	int index_var = tap_length / 8;
 
 	int bit_index = tap_length % 8;
 	uint8_t bit = 1 << bit_index;
 
 	if (tms)
-	{
-		tms_buffer[index] |= bit;
-	}
+		tms_buffer[index_var] |= bit;
 	else
-	{
-		tms_buffer[index] &= ~bit;
-	}
+		tms_buffer[index_var] &= ~bit;
 
 	if (tdi)
-	{
-		tdi_buffer[index] |= bit;
-	}
+		tdi_buffer[index_var] |= bit;
 	else
-	{
-		tdi_buffer[index] &= ~bit;
-	}
+		tdi_buffer[index_var] &= ~bit;
 
 	tap_length++;
+
 	if (tap_buffer_size * 8 <= tap_length)
-	{
 		vsllink_tap_execute();
-	}
 }
 
-static void vsllink_tap_append_scan(int length, uint8_t *buffer, \
-										struct scan_command *command)
+static void vsllink_tap_append_scan(int length, uint8_t *buffer,
+	struct scan_command *command)
 {
 	struct pending_scan_result *pending_scan_result;
 	int len_tmp, len_all, i;
 
 	len_all = 0;
-	while (len_all < length)
-	{
+	while (len_all < length) {
 		vsllink_tap_ensure_pending(1);
-		pending_scan_result = \
-				&pending_scan_results_buffer[pending_scan_results_length];
+		pending_scan_result =
+			&pending_scan_results_buffer[
+				pending_scan_results_length];
 
-		if ((length - len_all) > (tap_buffer_size * 8 - tap_length))
-		{
-			/* Use all memory available 
+		if ((length - len_all) > (tap_buffer_size * 8 - tap_length)) {
+			/* Use all memory available
 			   vsllink_tap_append_step will commit automatically */
 			len_tmp = tap_buffer_size * 8 - tap_length;
 			pending_scan_result->last = false;
-		}
-		else
-		{
+		} else {
 			len_tmp = length - len_all;
 			pending_scan_result->last = true;
 		}
@@ -796,134 +596,63 @@ static void vsllink_tap_append_scan(int length, uint8_t *buffer, \
 		pending_scan_result->buffer = buffer;
 		pending_scan_results_length++;
 
-		for (i = 0; i < len_tmp; i++)
-		{
-			vsllink_tap_append_step(((len_all + i) < length-1 ? 0 : 1), \
-						(buffer[(len_all + i)/8] >> ((len_all + i)%8)) & 1);
+		for (i = 0; i < len_tmp; i++) {
+			vsllink_tap_append_step(((len_all + i) < length-1
+						 ? 0 : 1),
+				(buffer[(len_all + i)/8]
+				 >> ((len_all + i)%8)) & 1);
 		}
 
 		len_all += len_tmp;
 	}
 }
 
-static int vsllink_tap_execute(void)
+static int vsllink_jtag_execute(void)
 {
-	int byte_length;
 	int i;
 	int result;
 
 	if (tap_length <= 0)
-	{
 		return ERROR_OK;
-	}
 
-	/* Pad data so that tap_length is divisible by 8 */
-	if ((tap_length % 8) != 0)
-	{
-		if (vsllink_tms_offset > 0)
-		{
-			/* append tms:0 at vsllink_tms_offset, which is in Pause */
-			int start_pos = DIV_ROUND_UP(tap_length, 8) - 1;
-			int end_pos = DIV_ROUND_UP(vsllink_tms_offset, 8) - 1;
-			int shift_cnt = (start_pos + 1) * 8 - tap_length;
-			uint8_t last_mask = ~((1 << (vsllink_tms_offset % 8)) - 1);
-
-			while (1)
-			{
-				if (start_pos == end_pos)
-				{
-					tms_buffer[start_pos] = \
-								(tms_buffer[start_pos] & ~last_mask) | \
-								((tms_buffer[start_pos] & last_mask) << shift_cnt);
-					tdi_buffer[start_pos] = \
-								(tdi_buffer[start_pos] & ~last_mask) | \
-								((tdi_buffer[start_pos] & last_mask) << shift_cnt);
-					break;
-				}
-				else if (start_pos == (end_pos + 1))
-				{
-					tms_buffer[start_pos] = \
-						(tms_buffer[start_pos] << shift_cnt) | \
-						((tms_buffer[start_pos - 1] & last_mask) >> (8 - shift_cnt));
-					tdi_buffer[start_pos] = \
-						(tdi_buffer[start_pos] << shift_cnt) | \
-						((tdi_buffer[start_pos - 1] & last_mask) >> (8 - shift_cnt));
-				}
-				else
-				{
-					tms_buffer[start_pos] = \
-						(tms_buffer[start_pos] << shift_cnt) | \
-						(tms_buffer[start_pos - 1] >> (8 - shift_cnt));
-					tdi_buffer[start_pos] = \
-						(tdi_buffer[start_pos] << shift_cnt) | \
-						(tdi_buffer[start_pos - 1] >> (8 - shift_cnt));
-				}
-				start_pos--;
-			}
-			tap_length = DIV_ROUND_UP(tap_length, 8) * 8;
-		}
-		else
-		{
-			/* append data at last */
-			while ((tap_length % 8) != 0)
-			{
-				vsllink_tap_append_step((tap_get_state() == TAP_RESET)?1:0, 0);
-			}
-		}
-	}
-	byte_length = tap_length / 8;
+	versaloon_interface.adaptors.jtag_raw.execute(0, tdi_buffer, tms_buffer,
+		tdo_buffer, tap_length);
 
-	vsllink_usb_out_buffer[0] = VSLLINK_CMD_HW_JTAGRAWCMD;
-	vsllink_usb_out_buffer[1] = ((byte_length * 2 + 3) >> 0) & 0xff;
-	vsllink_usb_out_buffer[2] = ((byte_length * 2 + 3) >> 8) & 0xff;
+	result = versaloon_interface.adaptors.peripheral_commit();
 
-	memcpy(&vsllink_usb_out_buffer[3], tdi_buffer, byte_length);
-	memcpy(&vsllink_usb_out_buffer[3 + byte_length], tms_buffer, byte_length);
-
-	result = vsllink_usb_message(vsllink_handle, 3 + 2 * byte_length, \
-									byte_length);
-
-	if (result == byte_length)
-	{
-		for (i = 0; i < pending_scan_results_length; i++)
-		{
-			struct pending_scan_result *pending_scan_result = \
-											&pending_scan_results_buffer[i];
+	if (result == ERROR_OK) {
+		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 src_first = pending_scan_result->src_offset;
 			int dest_first = pending_scan_result->dest_offset;
 			bool last = pending_scan_result->last;
 
-			struct scan_command *command = pending_scan_result->command;
-			buf_set_buf(vsllink_usb_in_buffer, src_first, buffer, \
-							dest_first, length);
+			struct scan_command *command;
 
-			DEBUG_JTAG_IO("JTAG scan read(%d bits, from %d bits):", \
-							length, dest_first);
-#ifdef _DEBUG_JTAG_IO_
-			vsllink_debug_buffer(buffer + dest_first / 8, DIV_ROUND_UP(length, 7));
-#endif
+			command = pending_scan_result->command;
+			buf_set_buf(tdo_buffer, src_first, buffer, dest_first, length);
 
-			if (last)
-			{
-				if (jtag_read_buffer(buffer, command) != ERROR_OK)
-				{
+			LOG_DEBUG_IO(
+				"JTAG scan read(%d bits, from src %d bits to dest %d bits):",
+				length, src_first, dest_first);
+			if (LOG_LEVEL_IS(LOG_LVL_DEBUG_IO))
+				vsllink_debug_buffer(buffer + dest_first / 8, DIV_ROUND_UP(length, 7));
+
+			if (last) {
+				if (jtag_read_buffer(buffer, command)
+				    != ERROR_OK) {
 					vsllink_tap_init();
 					return ERROR_JTAG_QUEUE_FAILED;
 				}
 
-				if (pending_scan_result->buffer != NULL)
-				{
-					free(pending_scan_result->buffer);
-				}
+				free(pending_scan_result->buffer);
 			}
 		}
-	}
-	else
-	{
-		LOG_ERROR("vsllink_tap_execute, wrong result %d, expected %d", \
-					result, byte_length);
+	} else {
+		LOG_ERROR("vsllink_jtag_execute failure");
 		return ERROR_JTAG_QUEUE_FAILED;
 	}
 
@@ -932,153 +661,191 @@ static int vsllink_tap_execute(void)
 	return ERROR_OK;
 }
 
-/*****************************************************************************/
-/* VSLLink USB low-level functions */
+static int vsllink_tap_execute(void)
+{
+	if (swd_mode)
+		return ERROR_OK;
 
-static struct vsllink* vsllink_usb_open(void)
+	return vsllink_jtag_execute();
+}
+
+static int vsllink_swd_init(void)
 {
-	usb_init();
-
-	const uint16_t vids[] = { vsllink_usb_vid, 0 };
-	const uint16_t pids[] = { vsllink_usb_pid, 0 };
-	struct usb_dev_handle *dev;
-	if (jtag_usb_open(vids, pids, &dev) != ERROR_OK)
-		return NULL;
-
-	/* usb_set_configuration required under win32 */
-	struct usb_device *udev = usb_device(dev);
-	int ret = usb_set_configuration(dev, udev->config[0].bConfigurationValue);
-	if (ret != 0)
-	{
-		LOG_ERROR("fail to set configuration to %d (error %d)."
-				"Not enough permissions for the device?",
-				udev->config[0].bConfigurationValue, ret);
-		return NULL;
-	}
-	ret = usb_claim_interface(dev, vsllink_usb_interface);
-	if (ret != 0)
-	{
-		LOG_ERROR("fail to claim interface %d, %d returned",
-				vsllink_usb_interface, ret);
-		return NULL;
-	}
-#if 0
-	/*
-	* This makes problems under Mac OS X. And is not needed
-	* under Windows. Hopefully this will not break a linux build
-	*/
-	usb_set_altinterface(dev, 0);
-#endif
+	LOG_INFO("VSLLink SWD mode enabled");
+	swd_mode = true;
 
-	struct vsllink *result = malloc(sizeof(struct vsllink));
-	result->usb_handle = dev;
-	return result;
+	return ERROR_OK;
 }
 
-static void vsllink_usb_close(struct vsllink *vsllink)
+static int_least32_t vsllink_swd_frequency(int_least32_t hz)
 {
-	int ret;
+	const int_least32_t delay2hz[] = {
+		1850000, 235000, 130000, 102000, 85000, 72000
+	};
 
-	ret = usb_release_interface(vsllink->usb_handle, vsllink_usb_interface);
-	if (ret != 0)
-	{
-		LOG_ERROR("fail to release interface %d, %d returned", \
-					vsllink_usb_interface, ret);
-		exit(-1);
+	if (hz > 0) {
+		uint16_t delay = UINT16_MAX;
+
+		for (uint16_t i = 0; i < ARRAY_SIZE(delay2hz); i++) {
+			if (hz >= delay2hz[i]) {
+				hz = delay2hz[i];
+				delay = i;
+				break;
+			}
+		}
+
+		if (delay == UINT16_MAX)
+			delay = (500000 / hz) - 1;
+
+		/* Calculate retry count after a WAIT response. This will give
+		 * a retry timeout at about ~250 ms. 54 is the number of bits
+		 * found in a transaction. */
+		uint16_t retry_count = 250 * hz / 1000 / 54;
+
+		LOG_DEBUG("SWD delay: %d, retry count: %d", delay, retry_count);
+
+		versaloon_interface.adaptors.swd.config(0, 2, retry_count, delay);
 	}
 
-	ret = usb_close(vsllink->usb_handle);
-	if (ret != 0)
-	{
-		LOG_ERROR("fail to close usb, %d returned", ret);
-		exit(-1);
+	return hz;
+}
+
+static int vsllink_swd_switch_seq(enum swd_special_seq seq)
+{
+	switch (seq) {
+	case LINE_RESET:
+		LOG_DEBUG("SWD line reset");
+		versaloon_interface.adaptors.swd.seqout(0, swd_seq_line_reset,
+				swd_seq_line_reset_len);
+		break;
+	case JTAG_TO_SWD:
+		LOG_DEBUG("JTAG-to-SWD");
+		versaloon_interface.adaptors.swd.seqout(0, swd_seq_jtag_to_swd,
+				swd_seq_jtag_to_swd_len);
+		break;
+	case SWD_TO_JTAG:
+		LOG_DEBUG("SWD-to-JTAG");
+		versaloon_interface.adaptors.swd.seqout(0, swd_seq_swd_to_jtag,
+				swd_seq_swd_to_jtag_len);
+		break;
+	default:
+		LOG_ERROR("Sequence %d not supported", seq);
+		return ERROR_FAIL;
 	}
 
-	free(vsllink);
+	return ERROR_OK;
 }
 
-/* Send a message and receive the reply. */
-static int vsllink_usb_message(struct vsllink *vsllink, int out_length, \
-								int in_length)
+static void vsllink_swd_read_reg(uint8_t cmd, uint32_t *value, uint32_t ap_delay_clk)
 {
-	int result;
+	versaloon_interface.adaptors.swd.transact(0, cmd, value, NULL);
+}
 
-	result = vsllink_usb_write(vsllink, out_length);
-	if (result == out_length)
-	{
-		if (in_length > 0)
-		{
-			result = vsllink_usb_read(vsllink);
-			if (result == in_length)
-			{
-				return result;
-			}
-			else
-			{
-				LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)", \
-							in_length, result);
-				return -1;
-			}
-		}
-		return 0;
-	}
-	else
-	{
-		LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)", \
-					out_length, result);
-		return -1;
-	}
+static void vsllink_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay_clk)
+{
+	versaloon_interface.adaptors.swd.transact(0, cmd, &value, NULL);
 }
 
-/* Write data from out_buffer to USB. */
-static int vsllink_usb_write(struct vsllink *vsllink, int out_length)
+static int vsllink_swd_run_queue(void)
 {
-	int result;
+	return versaloon_interface.adaptors.peripheral_commit();
+}
 
-	if (out_length > vsllink_buffer_size)
-	{
-		LOG_ERROR("vsllink_write illegal out_length=%d (max=%d)", \
-					out_length, vsllink_buffer_size);
-		return -1;
-	}
+/****************************************************************************
+ * VSLLink USB low-level functions */
 
-	result = usb_bulk_write(vsllink->usb_handle, vsllink_usb_bulkout, \
-		(char *)vsllink_usb_out_buffer, out_length, VSLLINK_USB_TIMEOUT);
+static int vsllink_check_usb_strings(
+	struct libusb_device_handle *usb_device_handle,
+	struct libusb_device_descriptor *usb_desc)
+{
+	char desc_string[256];
+	int retval;
 
-	DEBUG_JTAG_IO("vsllink_usb_write, out_length = %d, result = %d", \
-					out_length, result);
+	if (adapter_get_required_serial()) {
+		retval = libusb_get_string_descriptor_ascii(usb_device_handle,
+			usb_desc->iSerialNumber, (unsigned char *)desc_string,
+			sizeof(desc_string));
+		if (retval < 0)
+			return ERROR_FAIL;
 
-#ifdef _DEBUG_USB_COMMS_
-	LOG_DEBUG("USB out:");
-	vsllink_debug_buffer(vsllink_usb_out_buffer, out_length);
-#endif
+		if (strncmp(desc_string, adapter_get_required_serial(),
+				sizeof(desc_string)))
+			return ERROR_FAIL;
+	}
 
-#ifdef _VSLLINK_IN_DEBUG_MODE_
-	usleep(100000);
-#endif
+	retval = libusb_get_string_descriptor_ascii(usb_device_handle,
+		usb_desc->iProduct, (unsigned char *)desc_string,
+		sizeof(desc_string));
+	if (retval < 0)
+		return ERROR_FAIL;
+
+	if (!strstr(desc_string, "Versaloon"))
+		return ERROR_FAIL;
 
-	return result;
+	return ERROR_OK;
 }
 
-/* Read data from USB into in_buffer. */
-static int vsllink_usb_read(struct vsllink *vsllink)
+static int vsllink_usb_open(struct vsllink *vsllink)
 {
-	int result = usb_bulk_read(vsllink->usb_handle, vsllink_usb_bulkin, \
-		(char *)vsllink_usb_in_buffer, vsllink_buffer_size, \
-		VSLLINK_USB_TIMEOUT);
+	ssize_t num_devices, i;
+	struct libusb_device **usb_devices;
+	struct libusb_device_descriptor usb_desc;
+	struct libusb_device_handle *usb_device_handle;
+	int retval;
 
-	DEBUG_JTAG_IO("vsllink_usb_read, result = %d", result);
+	num_devices = libusb_get_device_list(vsllink->libusb_ctx, &usb_devices);
 
-#ifdef _DEBUG_USB_COMMS_
-	LOG_DEBUG("USB in:");
-	vsllink_debug_buffer(vsllink_usb_in_buffer, result);
-#endif
-	return result;
+	if (num_devices <= 0)
+		return ERROR_FAIL;
+
+	for (i = 0; i < num_devices; i++) {
+		struct libusb_device *device = usb_devices[i];
+
+		retval = libusb_get_device_descriptor(device, &usb_desc);
+		if (retval != 0)
+			continue;
+
+		if (usb_desc.idVendor != versaloon_interface.usb_setting.vid ||
+			usb_desc.idProduct != versaloon_interface.usb_setting.pid)
+			continue;
+
+		retval = libusb_open(device, &usb_device_handle);
+		if (retval != 0)
+			continue;
+
+		retval = vsllink_check_usb_strings(usb_device_handle, &usb_desc);
+		if (retval == ERROR_OK)
+			break;
+
+		libusb_close(usb_device_handle);
+	}
+
+	libusb_free_device_list(usb_devices, 1);
+
+	if (i == num_devices)
+		return ERROR_FAIL;
+
+	retval = libusb_claim_interface(usb_device_handle,
+		versaloon_interface.usb_setting.interface);
+	if (retval != 0) {
+		LOG_ERROR("unable to claim interface");
+		libusb_close(usb_device_handle);
+		return ERROR_FAIL;
+	}
+
+	vsllink->usb_device_handle = usb_device_handle;
+	return ERROR_OK;
+}
+
+static void vsllink_usb_close(struct vsllink *vsllink)
+{
+	libusb_release_interface(vsllink->usb_device_handle,
+		versaloon_interface.usb_setting.interface);
+	libusb_close(vsllink->usb_device_handle);
 }
 
 #define BYTES_PER_LINE  16
 
-#if defined _DEBUG_USB_COMMS_ || defined _DEBUG_JTAG_IO_
 static void vsllink_debug_buffer(uint8_t *buffer, int length)
 {
 	char line[81];
@@ -1086,61 +853,93 @@ static void vsllink_debug_buffer(uint8_t *buffer, int length)
 	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++)
-		{
+	for (i = 0; i < length; i += BYTES_PER_LINE) {
+		snprintf(line, 5, "%04x", i & 0xffff);
+		for (j = i; j < i + BYTES_PER_LINE && j < length; j++) {
 			snprintf(s, 4, " %02x", buffer[j]);
 			strcat(line, s);
 		}
-		LOG_DEBUG("%s", line);
+		LOG_DEBUG_IO("%s", line);
 	}
 }
-#endif // _DEBUG_USB_COMMS_ || _DEBUG_JTAG_IO_
 
-static const struct command_registration vsllink_command_handlers[] = {
+static const struct command_registration vsllink_subcommand_handlers[] = {
 	{
-		.name = "vsllink_usb_vid",
+		.name = "usb_vid",
 		.handler = &vsllink_handle_usb_vid_command,
 		.mode = COMMAND_CONFIG,
+		.help = "Set USB VID",
+		.usage = "<vid>",
 	},
 	{
-		.name = "vsllink_usb_pid",
+		.name = "usb_pid",
 		.handler = &vsllink_handle_usb_pid_command,
 		.mode = COMMAND_CONFIG,
+		.help = "Set USB PID",
+		.usage = "<pid>",
 	},
 	{
-		.name = "vsllink_usb_bulkin",
+		.name = "usb_bulkin",
 		.handler = &vsllink_handle_usb_bulkin_command,
 		.mode = COMMAND_CONFIG,
+		.help = "Set USB input endpoint",
+		.usage = "<ep_in>",
 	},
 	{
-		.name = "vsllink_usb_bulkout",
+		.name = "usb_bulkout",
 		.handler = &vsllink_handle_usb_bulkout_command,
 		.mode = COMMAND_CONFIG,
+		.help = "Set USB output endpoint",
+		.usage = "<ep_out>",
 	},
 	{
-		.name = "vsllink_usb_interface",
+		.name = "usb_interface",
 		.handler = &vsllink_handle_usb_interface_command,
 		.mode = COMMAND_CONFIG,
+		.help = "Set USB output interface",
+		.usage = "<interface>",
 	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration vsllink_command_handlers[] = {
 	{
-		.name = "vsllink_mode",
-		.handler = &vsllink_handle_mode_command,
-		.mode = COMMAND_CONFIG,
+		.name = "vsllink",
+		.mode = COMMAND_ANY,
+		.help = "perform vsllink management",
+		.chain = vsllink_subcommand_handlers,
+		.usage = "",
 	},
 	COMMAND_REGISTRATION_DONE
 };
 
-struct jtag_interface vsllink_interface = {
+static const char * const vsllink_transports[] = {"jtag", "swd", NULL};
+
+static const struct swd_driver vsllink_swd_driver = {
+	.init = vsllink_swd_init,
+	.switch_seq = vsllink_swd_switch_seq,
+	.read_reg = vsllink_swd_read_reg,
+	.write_reg = vsllink_swd_write_reg,
+	.run = vsllink_swd_run_queue,
+};
+
+static struct jtag_interface vsllink_interface = {
+	.supported = DEBUG_CAP_TMS_SEQ,
+	.execute_queue = vsllink_execute_queue,
+};
+
+struct adapter_driver vsllink_adapter_driver = {
 	.name = "vsllink",
+	.transports = vsllink_transports,
 	.commands = vsllink_command_handlers,
 
 	.init = vsllink_init,
 	.quit = vsllink_quit,
-	.khz = vsllink_khz,
+	.reset = vsllink_reset,
 	.speed = vsllink_speed,
+	.khz = vsllink_khz,
 	.speed_div = vsllink_speed_div,
-	.execute_queue = vsllink_execute_queue,
+
+	.jtag_ops = &vsllink_interface,
+	.swd_ops = &vsllink_swd_driver,
 };