X-Git-Url: https://review.openocd.org/gitweb?a=blobdiff_plain;f=src%2Fjtag%2Fdrivers%2Fcmsis_dap_usb.c;h=231e7c81b71e92c6ecdf0ea805765590023192cc;hb=55abb63752196de5a2e79fc4944a6af24e6414f6;hp=345c1fd7e8f62b127c1abbbe41c16eda5dd3b861;hpb=06aebfacda1f60052f6ea0f3d09936184e1bfab8;p=openocd.git

diff --git a/src/jtag/drivers/cmsis_dap_usb.c b/src/jtag/drivers/cmsis_dap_usb.c
index 345c1fd7e8..231e7c81b7 100644
--- a/src/jtag/drivers/cmsis_dap_usb.c
+++ b/src/jtag/drivers/cmsis_dap_usb.c
@@ -206,6 +206,8 @@ static uint8_t queued_seq_buf[1024]; /* TODO: make dynamic / move into cmsis obj
 
 static int queued_retval;
 
+static uint8_t output_pins = SWJ_PIN_SRST | SWJ_PIN_TRST;
+
 static struct cmsis_dap *cmsis_dap_handle;
 
 static int cmsis_dap_usb_open(void)
@@ -790,15 +792,20 @@ static int cmsis_dap_swd_switch_seq(enum swd_special_seq seq)
 	unsigned int s_len;
 	int retval;
 
-	/* First disconnect before connecting, Atmel EDBG needs it for SAMD/R/L/C */
-	cmsis_dap_cmd_DAP_Disconnect();
+	if ((output_pins & (SWJ_PIN_SRST | SWJ_PIN_TRST)) == (SWJ_PIN_SRST | SWJ_PIN_TRST)) {
+		/* Following workaround deasserts reset on most adapters.
+		 * Do not reconnect if a reset line is active!
+		 * Reconnecting would break connecting under reset. */
 
-	/* When we are reconnecting, DAP_Connect needs to be rerun, at
-	 * least on Keil ULINK-ME */
-	retval = cmsis_dap_cmd_DAP_Connect(seq == LINE_RESET || seq == JTAG_TO_SWD ?
-					   CONNECT_SWD : CONNECT_JTAG);
-	if (retval != ERROR_OK)
-		return retval;
+		/* First disconnect before connecting, Atmel EDBG needs it for SAMD/R/L/C */
+		cmsis_dap_cmd_DAP_Disconnect();
+
+		/* When we are reconnecting, DAP_Connect needs to be rerun, at
+		 * least on Keil ULINK-ME */
+		retval = cmsis_dap_cmd_DAP_Connect(CONNECT_SWD);
+		if (retval != ERROR_OK)
+			return retval;
+	}
 
 	switch (seq) {
 	case LINE_RESET:
@@ -834,17 +841,6 @@ static int cmsis_dap_swd_open(void)
 {
 	int retval;
 
-	if (cmsis_dap_handle == NULL) {
-		/* SWD init */
-		retval = cmsis_dap_usb_open();
-		if (retval != ERROR_OK)
-			return retval;
-
-		retval = cmsis_dap_get_caps_info();
-		if (retval != ERROR_OK)
-			return retval;
-	}
-
 	if (!(cmsis_dap_handle->caps & INFO_CAPS_SWD)) {
 		LOG_ERROR("CMSIS-DAP: SWD not supported");
 		return ERROR_JTAG_DEVICE_ERROR;
@@ -865,6 +861,18 @@ static int cmsis_dap_init(void)
 	int retval;
 	uint8_t *data;
 
+	retval = cmsis_dap_usb_open();
+	if (retval != ERROR_OK)
+		return retval;
+
+	retval = cmsis_dap_get_caps_info();
+	if (retval != ERROR_OK)
+		return retval;
+
+	retval = cmsis_dap_get_version_info();
+	if (retval != ERROR_OK)
+		return retval;
+
 	if (swd_mode) {
 		retval = cmsis_dap_swd_open();
 		if (retval != ERROR_OK)
@@ -872,16 +880,6 @@ static int cmsis_dap_init(void)
 	}
 
 	if (cmsis_dap_handle == NULL) {
-
-		/* JTAG init */
-		retval = cmsis_dap_usb_open();
-		if (retval != ERROR_OK)
-			return retval;
-
-		retval = cmsis_dap_get_caps_info();
-		if (retval != ERROR_OK)
-			return retval;
-
 		/* Connect in JTAG mode */
 		if (!(cmsis_dap_handle->caps & INFO_CAPS_JTAG)) {
 			LOG_ERROR("CMSIS-DAP: JTAG not supported");
@@ -895,10 +893,6 @@ static int cmsis_dap_init(void)
 		LOG_INFO("CMSIS-DAP: Interface Initialised (JTAG)");
 	}
 
-	retval = cmsis_dap_get_version_info();
-	if (retval != ERROR_OK)
-		return retval;
-
 	/* INFO_ID_PKT_SZ - short */
 	retval = cmsis_dap_cmd_DAP_Info(INFO_ID_PKT_SZ, &data);
 	if (retval != ERROR_OK)
@@ -1010,14 +1004,14 @@ static void cmsis_dap_execute_reset(struct jtag_command *cmd)
 {
 	/* Set both TRST and SRST even if they're not enabled as
 	 * there's no way to tristate them */
-	uint8_t pins = 0;
 
+	output_pins = 0;
 	if (!cmd->cmd.reset->srst)
-		pins |= SWJ_PIN_SRST;
+		output_pins |= SWJ_PIN_SRST;
 	if (!cmd->cmd.reset->trst)
-		pins |= SWJ_PIN_TRST;
+		output_pins |= SWJ_PIN_TRST;
 
-	int retval = cmsis_dap_cmd_DAP_SWJ_Pins(pins,
+	int retval = cmsis_dap_cmd_DAP_SWJ_Pins(output_pins,
 			SWJ_PIN_TRST | SWJ_PIN_SRST, 0, NULL);
 	if (retval != ERROR_OK)
 		LOG_ERROR("CMSIS-DAP: Interface reset failed");