Add Jtag to Dormant sequence in case the target has both jtag and swd…

… and is jtag by default

src/target/adiv5_internal.h

@@ -44,6 +44,11 @@
 #define ADIV5_SWD_TO_JTAG_SELECT_SEQUENCE 0xe73cU /* 16 bits, LSB (MSB: 0x3ce7) */
 #define ADIV5_JTAG_TO_SWD_SELECT_SEQUENCE 0xe79eU /* 16 bits, LSB (MSB: 0x79e7) */
 
+/* ADIv5 JTAG to dormant sequence */
+#define ADIV5_JTAG_TO_DORMANT_SEQUENCE0 0x1fU       /* 5 bits */
+#define ADIV5_JTAG_TO_DORMANT_SEQUENCE1 0x33bbbbbaU /* 31 bits, LSB  (MSB : 0x2eeeeee6) */
+#define ADIV5_JTAG_TO_DORMANT_SEQUENCE2 0xffU       /* 8 bits  */
+
 /*
  * ADIv5 Selection Alert sequence
  * This sequence is sent MSB first and can be represented as either:

src/target/adiv5_swd.c

@@ -75,11 +75,19 @@ static void dormant_to_swd_sequence(void)
 	 * §5.3.4 Switching out of Dormant state
 	 */
 
-	DEBUG_INFO("Switching out of dormant state into SWD\n");
-
 	/* Send at least 8 SWCLKTCK cycles with SWDIOTMS HIGH */
 	swd_line_reset_sequence(false);
+
+	/* 
+	 * If the target is both JTAG and SWD with JTAG as default, switch JTAG->DS first. 
+	 * See B5.3.2
+	 */
+	DEBUG_INFO("Switching from JTAG do dormant\n");
+	swd_proc.seq_out(ADIV5_JTAG_TO_DORMANT_SEQUENCE0, 5U);
+	swd_proc.seq_out(ADIV5_JTAG_TO_DORMANT_SEQUENCE1, 31U);
+	swd_proc.seq_out(ADIV5_JTAG_TO_DORMANT_SEQUENCE2, 8U);
 	/* Send the 128-bit Selection Alert sequence on SWDIOTMS */
+	DEBUG_INFO("Switching out of dormant state into SWD\n");
 	swd_proc.seq_out(ADIV5_SELECTION_ALERT_SEQUENCE_0, 32U);
 	swd_proc.seq_out(ADIV5_SELECTION_ALERT_SEQUENCE_1, 32U);
 	swd_proc.seq_out(ADIV5_SELECTION_ALERT_SEQUENCE_2, 32U);