jtag/drivers/ftdi: do not touch unavailable reset signals

If the current reset_config doesn't specify availability of nTRST or
nSRST, just leave them alone, do not try to deassert them ever
(asserting would be prevented by the upper layer).

Change-Id: I90123c666e05a1c26f1e164625e82d766a3e3744
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/2186
Tested-by: jenkins
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>

diff --git a/src/jtag/drivers/ftdi.c b/src/jtag/drivers/ftdi.c
index b65dd2ac444f66a265037597e3080fbe3bec1a9f..0debc2dcfd3b23c88dbdd012aac7de0c9eb810f2 100644 (file)
--- a/src/jtag/drivers/ftdi.c
+++ b/src/jtag/drivers/ftdi.c
@@ -501,7 +501,8 @@ static void ftdi_execute_reset(struct jtag_command *cmd)
                        ftdi_set_signal(trst, '0');
                else
                        LOG_ERROR("Can't assert TRST: nTRST signal is not defined");
-       } else if (trst && cmd->cmd.reset->trst == 0) {
+       } else if (trst && jtag_get_reset_config() & RESET_HAS_TRST &&
+                       cmd->cmd.reset->trst == 0) {
                if (jtag_get_reset_config() & RESET_TRST_OPEN_DRAIN)
                        ftdi_set_signal(trst, 'z');
                else
@@ -514,7 +515,8 @@ static void ftdi_execute_reset(struct jtag_command *cmd)
                        ftdi_set_signal(srst, '0');
                else
                        LOG_ERROR("Can't assert SRST: nSRST signal is not defined");
-       } else if (srst && cmd->cmd.reset->srst == 0) {
+       } else if (srst && jtag_get_reset_config() & RESET_HAS_SRST &&
+                       cmd->cmd.reset->srst == 0) {
                if (jtag_get_reset_config() & RESET_SRST_PUSH_PULL)
                        ftdi_set_signal(srst, '1');
                else