From 847f1209d644fb1db45f7a385d9592eba76ab688 Mon Sep 17 00:00:00 2001
From: Evan Hunter <ehunter@broadcom.com>
Date: Wed, 31 Oct 2012 17:51:45 +1100
Subject: [PATCH] jtag interfaces: Reduce usage of global for jtag queue

Makes driver interface slightly more flexible.

Change-Id: I2c7f5cb6d014e94a0e6122cbe2f4002c77fbabb9
Signed-off-by: Evan Hunter <ehunter@broadcom.com>
Signed-off-by: David Ryskalczyk <david.rysk@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/945
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: jenkins
---
 src/jtag/commands.c                        | 7 ++++++-
 src/jtag/commands.h                        | 4 +---
 src/jtag/core.c                            | 4 ++--
 src/jtag/drivers/amt_jtagaccel.c           | 4 ++--
 src/jtag/drivers/angie.c                   | 6 +++---
 src/jtag/drivers/arm-jtag-ew.c             | 4 ++--
 src/jtag/drivers/bitbang.c                 | 5 +++--
 src/jtag/drivers/bitbang.h                 | 3 ++-
 src/jtag/drivers/bitq.c                    | 6 +++---
 src/jtag/drivers/bitq.h                    | 2 +-
 src/jtag/drivers/buspirate.c               | 6 +++---
 src/jtag/drivers/cmsis_dap.c               | 4 ++--
 src/jtag/drivers/ft232r.c                  | 4 ++--
 src/jtag/drivers/ftdi.c                    | 4 ++--
 src/jtag/drivers/gw16012.c                 | 4 ++--
 src/jtag/drivers/jlink.c                   | 4 ++--
 src/jtag/drivers/jtag_dpi.c                | 4 ++--
 src/jtag/drivers/jtag_vpi.c                | 4 ++--
 src/jtag/drivers/opendous.c                | 6 +++---
 src/jtag/drivers/openjtag.c                | 4 ++--
 src/jtag/drivers/osbdm.c                   | 4 ++--
 src/jtag/drivers/remote_bitbang.c          | 4 ++--
 src/jtag/drivers/rlink.c                   | 4 ++--
 src/jtag/drivers/ulink.c                   | 6 +++---
 src/jtag/drivers/usb_blaster/usb_blaster.c | 4 ++--
 src/jtag/drivers/usbprog.c                 | 4 ++--
 src/jtag/drivers/vdebug.c                  | 4 ++--
 src/jtag/drivers/vsllink.c                 | 4 ++--
 src/jtag/drivers/xds110.c                  | 4 ++--
 src/jtag/drivers/xlnx-pcie-xvc.c           | 4 ++--
 src/jtag/interface.h                       | 6 ++++--
 31 files changed, 72 insertions(+), 65 deletions(-)

diff --git a/src/jtag/commands.c b/src/jtag/commands.c
index 43cda8ad4e..c36c219233 100644
--- a/src/jtag/commands.c
+++ b/src/jtag/commands.c
@@ -33,7 +33,7 @@ struct cmd_queue_page {
 static struct cmd_queue_page *cmd_queue_pages;
 static struct cmd_queue_page *cmd_queue_pages_tail;
 
-struct jtag_command *jtag_command_queue;
+static struct jtag_command *jtag_command_queue;
 static struct jtag_command **next_command_pointer = &jtag_command_queue;
 
 void jtag_queue_command(struct jtag_command *cmd)
@@ -147,6 +147,11 @@ void jtag_command_queue_reset(void)
 	next_command_pointer = &jtag_command_queue;
 }
 
+struct jtag_command *jtag_command_queue_get(void)
+{
+	return jtag_command_queue;
+}
+
 /**
  * Copy a struct scan_field for insertion into the queue.
  *
diff --git a/src/jtag/commands.h b/src/jtag/commands.h
index a8c7ffdc66..a1096daa77 100644
--- a/src/jtag/commands.h
+++ b/src/jtag/commands.h
@@ -149,13 +149,11 @@ struct jtag_command {
 	struct jtag_command *next;
 };
 
-/** The current queue of jtag_command_s structures. */
-extern struct jtag_command *jtag_command_queue;
-
 void *cmd_queue_alloc(size_t size);
 
 void jtag_queue_command(struct jtag_command *cmd);
 void jtag_command_queue_reset(void);
+struct jtag_command *jtag_command_queue_get(void);
 
 void jtag_scan_field_clone(struct scan_field *dst, const struct scan_field *src);
 enum scan_type jtag_scan_type(const struct scan_command *cmd);
diff --git a/src/jtag/core.c b/src/jtag/core.c
index e2af6c53d9..c84d5aa3d3 100644
--- a/src/jtag/core.c
+++ b/src/jtag/core.c
@@ -951,9 +951,9 @@ int default_interface_jtag_execute_queue(void)
 			return ERROR_OK;
 	}
 
-	int result = adapter_driver->jtag_ops->execute_queue();
+	struct jtag_command *cmd = jtag_command_queue_get();
+	int result = adapter_driver->jtag_ops->execute_queue(cmd);
 
-	struct jtag_command *cmd = jtag_command_queue;
 	while (debug_level >= LOG_LVL_DEBUG_IO && cmd) {
 		switch (cmd->type) {
 			case JTAG_SCAN:
diff --git a/src/jtag/drivers/amt_jtagaccel.c b/src/jtag/drivers/amt_jtagaccel.c
index a4c8f32122..b28ce62ffb 100644
--- a/src/jtag/drivers/amt_jtagaccel.c
+++ b/src/jtag/drivers/amt_jtagaccel.c
@@ -317,9 +317,9 @@ static void amt_jtagaccel_scan(bool ir_scan, enum scan_type type, uint8_t *buffe
 	tap_set_state(tap_get_end_state());
 }
 
-static int amt_jtagaccel_execute_queue(void)
+static int amt_jtagaccel_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;	/* currently processed command */
+	struct jtag_command *cmd = cmd_queue;	/* currently processed command */
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
diff --git a/src/jtag/drivers/angie.c b/src/jtag/drivers/angie.c
index 62079f0156..c024667bdb 100644
--- a/src/jtag/drivers/angie.c
+++ b/src/jtag/drivers/angie.c
@@ -233,7 +233,7 @@ static int angie_post_process_scan(struct angie_cmd *angie_cmd);
 static int angie_post_process_queue(struct angie *device);
 
 /* adapter driver functions */
-static int angie_execute_queue(void);
+static int angie_execute_queue(struct jtag_command *cmd_queue);
 static int angie_khz(int khz, int *jtag_speed);
 static int angie_speed(int speed);
 static int angie_speed_div(int speed, int *khz);
@@ -2037,9 +2037,9 @@ static int angie_post_process_queue(struct angie *device)
  * @return on success: ERROR_OK
  * @return on failure: ERROR_FAIL
  */
-static int angie_execute_queue(void)
+static int angie_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 	int ret;
 
 	while (cmd) {
diff --git a/src/jtag/drivers/arm-jtag-ew.c b/src/jtag/drivers/arm-jtag-ew.c
index eada67f45c..4c50c54c9b 100644
--- a/src/jtag/drivers/arm-jtag-ew.c
+++ b/src/jtag/drivers/arm-jtag-ew.c
@@ -85,9 +85,9 @@ static struct armjtagew *armjtagew_handle;
 /**************************************************************************
  * External interface implementation */
 
-static int armjtagew_execute_queue(void)
+static int armjtagew_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;
diff --git a/src/jtag/drivers/bitbang.c b/src/jtag/drivers/bitbang.c
index 186d2098af..8df51764b7 100644
--- a/src/jtag/drivers/bitbang.c
+++ b/src/jtag/drivers/bitbang.c
@@ -15,6 +15,7 @@
 #include "config.h"
 #endif
 
+#include <jtag/jtag.h>      /* Added to avoid include loop in commands.h */
 #include "bitbang.h"
 #include <jtag/interface.h>
 #include <jtag/commands.h>
@@ -287,9 +288,9 @@ static void bitbang_sleep(unsigned int microseconds)
 	}
 }
 
-int bitbang_execute_queue(void)
+int bitbang_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;	/* currently processed command */
+	struct jtag_command *cmd = cmd_queue;	/* currently processed command */
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
diff --git a/src/jtag/drivers/bitbang.h b/src/jtag/drivers/bitbang.h
index 097a5c0d12..dc941796e2 100644
--- a/src/jtag/drivers/bitbang.h
+++ b/src/jtag/drivers/bitbang.h
@@ -12,6 +12,7 @@
 #define OPENOCD_JTAG_DRIVERS_BITBANG_H
 
 #include <jtag/swd.h>
+#include <jtag/commands.h>
 
 typedef enum {
 	BB_LOW,
@@ -64,7 +65,7 @@ struct bitbang_interface {
 
 extern const struct swd_driver bitbang_swd;
 
-int bitbang_execute_queue(void);
+int bitbang_execute_queue(struct jtag_command *cmd_queue);
 
 extern struct bitbang_interface *bitbang_interface;
 
diff --git a/src/jtag/drivers/bitq.c b/src/jtag/drivers/bitq.c
index 59e4f3574c..2e5cca2a49 100644
--- a/src/jtag/drivers/bitq.c
+++ b/src/jtag/drivers/bitq.c
@@ -203,11 +203,11 @@ static void bitq_scan(struct scan_command *cmd)
 	bitq_scan_field(&cmd->fields[i], 1);
 }
 
-int bitq_execute_queue(void)
+int bitq_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue; /* currently processed command */
+	struct jtag_command *cmd = cmd_queue; /* currently processed command */
 
-	bitq_in_state.cmd = jtag_command_queue;
+	bitq_in_state.cmd = cmd_queue;
 	bitq_in_state.field_idx = 0;
 	bitq_in_state.bit_pos   = 0;
 	bitq_in_state.status    = ERROR_OK;
diff --git a/src/jtag/drivers/bitq.h b/src/jtag/drivers/bitq.h
index 8e06fcf737..3ed182da4c 100644
--- a/src/jtag/drivers/bitq.h
+++ b/src/jtag/drivers/bitq.h
@@ -27,7 +27,7 @@ struct bitq_interface {
 
 extern struct bitq_interface *bitq_interface;
 
-int bitq_execute_queue(void);
+int bitq_execute_queue(struct jtag_command *cmd_queue);
 
 void bitq_cleanup(void);
 
diff --git a/src/jtag/drivers/buspirate.c b/src/jtag/drivers/buspirate.c
index 03b48e68b2..3b03337c94 100644
--- a/src/jtag/drivers/buspirate.c
+++ b/src/jtag/drivers/buspirate.c
@@ -20,7 +20,7 @@
 
 #undef DEBUG_SERIAL
 /*#define DEBUG_SERIAL */
-static int buspirate_execute_queue(void);
+static int buspirate_execute_queue(struct jtag_command *cmd_queue);
 static int buspirate_init(void);
 static int buspirate_quit(void);
 static int buspirate_reset(int trst, int srst);
@@ -151,10 +151,10 @@ static int buspirate_serial_read(int fd, uint8_t *buf, int size);
 static void buspirate_serial_close(int fd);
 static void buspirate_print_buffer(uint8_t *buf, int size);
 
-static int buspirate_execute_queue(void)
+static int buspirate_execute_queue(struct jtag_command *cmd_queue)
 {
 	/* currently processed command */
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
diff --git a/src/jtag/drivers/cmsis_dap.c b/src/jtag/drivers/cmsis_dap.c
index caacc9b916..341d35cdfa 100644
--- a/src/jtag/drivers/cmsis_dap.c
+++ b/src/jtag/drivers/cmsis_dap.c
@@ -1954,9 +1954,9 @@ static void cmsis_dap_execute_command(struct jtag_command *cmd)
 	}
 }
 
-static int cmsis_dap_execute_queue(void)
+static int cmsis_dap_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 
 	while (cmd) {
 		cmsis_dap_execute_command(cmd);
diff --git a/src/jtag/drivers/ft232r.c b/src/jtag/drivers/ft232r.c
index 2d9d9ef34d..766f6ddb5d 100644
--- a/src/jtag/drivers/ft232r.c
+++ b/src/jtag/drivers/ft232r.c
@@ -803,9 +803,9 @@ static void syncbb_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int
 		}
 }
 
-static int syncbb_execute_queue(void)
+static int syncbb_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue; /* currently processed command */
+	struct jtag_command *cmd = cmd_queue; /* currently processed command */
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
diff --git a/src/jtag/drivers/ftdi.c b/src/jtag/drivers/ftdi.c
index da5911ac99..2bde93169e 100644
--- a/src/jtag/drivers/ftdi.c
+++ b/src/jtag/drivers/ftdi.c
@@ -625,14 +625,14 @@ static void ftdi_execute_command(struct jtag_command *cmd)
 	}
 }
 
-static int ftdi_execute_queue(void)
+static int ftdi_execute_queue(struct jtag_command *cmd_queue)
 {
 	/* blink, if the current layout has that feature */
 	struct signal *led = find_signal_by_name("LED");
 	if (led)
 		ftdi_set_signal(led, '1');
 
-	for (struct jtag_command *cmd = jtag_command_queue; cmd; cmd = cmd->next) {
+	for (struct jtag_command *cmd = cmd_queue; cmd; cmd = cmd->next) {
 		/* fill the write buffer with the desired command */
 		ftdi_execute_command(cmd);
 	}
diff --git a/src/jtag/drivers/gw16012.c b/src/jtag/drivers/gw16012.c
index 592e170992..a4c6fd0f00 100644
--- a/src/jtag/drivers/gw16012.c
+++ b/src/jtag/drivers/gw16012.c
@@ -270,9 +270,9 @@ static void gw16012_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int
 	}
 }
 
-static int gw16012_execute_queue(void)
+static int gw16012_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue; /* currently processed command */
+	struct jtag_command *cmd = cmd_queue; /* currently processed command */
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
diff --git a/src/jtag/drivers/jlink.c b/src/jtag/drivers/jlink.c
index 97dc351fdf..1874557dcd 100644
--- a/src/jtag/drivers/jlink.c
+++ b/src/jtag/drivers/jlink.c
@@ -276,10 +276,10 @@ static int jlink_execute_command(struct jtag_command *cmd)
 	return ERROR_OK;
 }
 
-static int jlink_execute_queue(void)
+static int jlink_execute_queue(struct jtag_command *cmd_queue)
 {
 	int ret;
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 
 	while (cmd) {
 		ret = jlink_execute_command(cmd);
diff --git a/src/jtag/drivers/jtag_dpi.c b/src/jtag/drivers/jtag_dpi.c
index 2a36331efc..285f96e4bf 100644
--- a/src/jtag/drivers/jtag_dpi.c
+++ b/src/jtag/drivers/jtag_dpi.c
@@ -222,12 +222,12 @@ static int jtag_dpi_stableclocks(int cycles)
 	return jtag_dpi_runtest(cycles);
 }
 
-static int jtag_dpi_execute_queue(void)
+static int jtag_dpi_execute_queue(struct jtag_command *cmd_queue)
 {
 	struct jtag_command *cmd;
 	int ret = ERROR_OK;
 
-	for (cmd = jtag_command_queue; ret == ERROR_OK && cmd;
+	for (cmd = cmd_queue; ret == ERROR_OK && cmd;
 	     cmd = cmd->next) {
 		switch (cmd->type) {
 		case JTAG_RUNTEST:
diff --git a/src/jtag/drivers/jtag_vpi.c b/src/jtag/drivers/jtag_vpi.c
index c2b3b08083..9dec0d19df 100644
--- a/src/jtag/drivers/jtag_vpi.c
+++ b/src/jtag/drivers/jtag_vpi.c
@@ -480,12 +480,12 @@ static int jtag_vpi_stableclocks(int cycles)
 	return ERROR_OK;
 }
 
-static int jtag_vpi_execute_queue(void)
+static int jtag_vpi_execute_queue(struct jtag_command *cmd_queue)
 {
 	struct jtag_command *cmd;
 	int retval = ERROR_OK;
 
-	for (cmd = jtag_command_queue; retval == ERROR_OK && cmd;
+	for (cmd = cmd_queue; retval == ERROR_OK && cmd;
 	     cmd = cmd->next) {
 		switch (cmd->type) {
 		case JTAG_RESET:
diff --git a/src/jtag/drivers/opendous.c b/src/jtag/drivers/opendous.c
index 4d9fd998a7..81b74d40ec 100644
--- a/src/jtag/drivers/opendous.c
+++ b/src/jtag/drivers/opendous.c
@@ -99,7 +99,7 @@ static char *opendous_type;
 static const struct opendous_probe *opendous_probe;
 
 /* External interface functions */
-static int opendous_execute_queue(void);
+static int opendous_execute_queue(struct jtag_command *cmd_queue);
 static int opendous_init(void);
 static int opendous_quit(void);
 
@@ -238,9 +238,9 @@ struct adapter_driver opendous_adapter_driver = {
 	.jtag_ops = &opendous_interface,
 };
 
-static int opendous_execute_queue(void)
+static int opendous_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;
diff --git a/src/jtag/drivers/openjtag.c b/src/jtag/drivers/openjtag.c
index 086a411d6b..ea78ca8fd6 100644
--- a/src/jtag/drivers/openjtag.c
+++ b/src/jtag/drivers/openjtag.c
@@ -805,9 +805,9 @@ static void openjtag_execute_command(struct jtag_command *cmd)
 	}
 }
 
-static int openjtag_execute_queue(void)
+static int openjtag_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 
 	while (cmd) {
 		openjtag_execute_command(cmd);
diff --git a/src/jtag/drivers/osbdm.c b/src/jtag/drivers/osbdm.c
index 84f2fd66a0..8d4fc90d88 100644
--- a/src/jtag/drivers/osbdm.c
+++ b/src/jtag/drivers/osbdm.c
@@ -628,7 +628,7 @@ static int osbdm_execute_command(
 	return retval;
 }
 
-static int osbdm_execute_queue(void)
+static int osbdm_execute_queue(struct jtag_command *cmd_queue)
 {
 	int retval = ERROR_OK;
 
@@ -637,7 +637,7 @@ static int osbdm_execute_queue(void)
 		LOG_ERROR("BUG: can't allocate bit queue");
 		retval = ERROR_FAIL;
 	} else {
-		struct jtag_command *cmd = jtag_command_queue;
+		struct jtag_command *cmd = cmd_queue;
 
 		while (retval == ERROR_OK && cmd) {
 			retval = osbdm_execute_command(&osbdm_context, queue, cmd);
diff --git a/src/jtag/drivers/remote_bitbang.c b/src/jtag/drivers/remote_bitbang.c
index 6d0fba2e40..c97b6b6abe 100644
--- a/src/jtag/drivers/remote_bitbang.c
+++ b/src/jtag/drivers/remote_bitbang.c
@@ -456,14 +456,14 @@ static const struct command_registration remote_bitbang_command_handlers[] = {
 	COMMAND_REGISTRATION_DONE
 };
 
-static int remote_bitbang_execute_queue(void)
+static int remote_bitbang_execute_queue(struct jtag_command *cmd_queue)
 {
 	/* safety: the send buffer must be empty, no leftover characters from
 	 * previous transactions */
 	assert(remote_bitbang_send_buf_used == 0);
 
 	/* process the JTAG command queue */
-	int ret = bitbang_execute_queue();
+	int ret = bitbang_execute_queue(cmd_queue);
 	if (ret != ERROR_OK)
 		return ret;
 
diff --git a/src/jtag/drivers/rlink.c b/src/jtag/drivers/rlink.c
index a28e76e013..1b1f2e4de6 100644
--- a/src/jtag/drivers/rlink.c
+++ b/src/jtag/drivers/rlink.c
@@ -1262,9 +1262,9 @@ static int rlink_scan(struct jtag_command *cmd, enum scan_type type,
 	return 0;
 }
 
-static int rlink_execute_queue(void)
+static int rlink_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;	/* currently processed command */
+	struct jtag_command *cmd = cmd_queue;	/* currently processed command */
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
diff --git a/src/jtag/drivers/ulink.c b/src/jtag/drivers/ulink.c
index fd29f126e2..4f23c6c7fa 100644
--- a/src/jtag/drivers/ulink.c
+++ b/src/jtag/drivers/ulink.c
@@ -227,7 +227,7 @@ static int ulink_post_process_scan(struct ulink_cmd *ulink_cmd);
 static int ulink_post_process_queue(struct ulink *device);
 
 /* adapter driver functions */
-static int ulink_execute_queue(void);
+static int ulink_execute_queue(struct jtag_command *cmd_queue);
 static int ulink_khz(int khz, int *jtag_speed);
 static int ulink_speed(int speed);
 static int ulink_speed_div(int speed, int *khz);
@@ -1905,9 +1905,9 @@ static int ulink_post_process_queue(struct ulink *device)
  * @return on success: ERROR_OK
  * @return on failure: ERROR_FAIL
  */
-static int ulink_execute_queue(void)
+static int ulink_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 	int ret;
 
 	while (cmd) {
diff --git a/src/jtag/drivers/usb_blaster/usb_blaster.c b/src/jtag/drivers/usb_blaster/usb_blaster.c
index 8c37048144..c84055c4a1 100644
--- a/src/jtag/drivers/usb_blaster/usb_blaster.c
+++ b/src/jtag/drivers/usb_blaster/usb_blaster.c
@@ -765,7 +765,7 @@ static void ublast_initial_wipeout(void)
 	tap_set_state(TAP_RESET);
 }
 
-static int ublast_execute_queue(void)
+static int ublast_execute_queue(struct jtag_command *cmd_queue)
 {
 	struct jtag_command *cmd;
 	static int first_call = 1;
@@ -776,7 +776,7 @@ static int ublast_execute_queue(void)
 		ublast_initial_wipeout();
 	}
 
-	for (cmd = jtag_command_queue; ret == ERROR_OK && cmd;
+	for (cmd = cmd_queue; ret == ERROR_OK && cmd;
 	     cmd = cmd->next) {
 		switch (cmd->type) {
 		case JTAG_RESET:
diff --git a/src/jtag/drivers/usbprog.c b/src/jtag/drivers/usbprog.c
index aa655ed7e6..2d666d0728 100644
--- a/src/jtag/drivers/usbprog.c
+++ b/src/jtag/drivers/usbprog.c
@@ -83,9 +83,9 @@ static void usbprog_jtag_write_slice(struct usbprog_jtag *usbprog_jtag, unsigned
 static void usbprog_jtag_set_bit(struct usbprog_jtag *usbprog_jtag, int bit, int value);
 /* static int usbprog_jtag_get_bit(struct usbprog_jtag *usbprog_jtag, int bit); */
 
-static int usbprog_execute_queue(void)
+static int usbprog_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;	/* currently processed command */
+	struct jtag_command *cmd = cmd_queue;	/* currently processed command */
 	int scan_size;
 	enum scan_type type;
 	uint8_t *buffer;
diff --git a/src/jtag/drivers/vdebug.c b/src/jtag/drivers/vdebug.c
index 6d9016e9c6..f1fc4535f3 100644
--- a/src/jtag/drivers/vdebug.c
+++ b/src/jtag/drivers/vdebug.c
@@ -1046,11 +1046,11 @@ static int vdebug_jtag_div(int speed, int *khz)
 	return ERROR_OK;
 }
 
-static int vdebug_jtag_execute_queue(void)
+static int vdebug_jtag_execute_queue(struct jtag_command *cmd_queue)
 {
 	int rc = ERROR_OK;
 
-	for (struct jtag_command *cmd = jtag_command_queue; rc == ERROR_OK && cmd; cmd = cmd->next) {
+	for (struct jtag_command *cmd = cmd_queue; rc == ERROR_OK && cmd; cmd = cmd->next) {
 		switch (cmd->type) {
 		case JTAG_RUNTEST:
 			rc = vdebug_jtag_runtest(cmd->cmd.runtest->num_cycles, cmd->cmd.runtest->end_state, !cmd->next);
diff --git a/src/jtag/drivers/vsllink.c b/src/jtag/drivers/vsllink.c
index 255ff88a2f..34525d5468 100644
--- a/src/jtag/drivers/vsllink.c
+++ b/src/jtag/drivers/vsllink.c
@@ -84,9 +84,9 @@ static bool swd_mode;
 
 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;
diff --git a/src/jtag/drivers/xds110.c b/src/jtag/drivers/xds110.c
index 717295c73c..11fbaaab2a 100644
--- a/src/jtag/drivers/xds110.c
+++ b/src/jtag/drivers/xds110.c
@@ -1840,9 +1840,9 @@ static void xds110_execute_command(struct jtag_command *cmd)
 	}
 }
 
-static int xds110_execute_queue(void)
+static int xds110_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 
 	while (cmd) {
 		xds110_execute_command(cmd);
diff --git a/src/jtag/drivers/xlnx-pcie-xvc.c b/src/jtag/drivers/xlnx-pcie-xvc.c
index 6ad0255e71..233ade3f88 100644
--- a/src/jtag/drivers/xlnx-pcie-xvc.c
+++ b/src/jtag/drivers/xlnx-pcie-xvc.c
@@ -362,9 +362,9 @@ static int xlnx_pcie_xvc_execute_command(struct jtag_command *cmd)
 	return ERROR_OK;
 }
 
-static int xlnx_pcie_xvc_execute_queue(void)
+static int xlnx_pcie_xvc_execute_queue(struct jtag_command *cmd_queue)
 {
-	struct jtag_command *cmd = jtag_command_queue;
+	struct jtag_command *cmd = cmd_queue;
 	int ret;
 
 	while (cmd) {
diff --git a/src/jtag/interface.h b/src/jtag/interface.h
index 3df424086d..28c1458cb0 100644
--- a/src/jtag/interface.h
+++ b/src/jtag/interface.h
@@ -187,10 +187,12 @@ struct jtag_interface {
 #define DEBUG_CAP_TMS_SEQ	(1 << 0)
 
 	/**
-	 * Execute queued commands.
+	 * Execute commands in the supplied queue
+	 * @param cmd_queue - a linked list of commands to execute
 	 * @returns ERROR_OK on success, or an error code on failure.
 	 */
-	int (*execute_queue)(void);
+
+	int (*execute_queue)(struct jtag_command *cmd_queue);
 };
 
 /**
-- 
2.30.2