From 0b248e04c1e58b374e82bad0361e42a5e8a96b77 Mon Sep 17 00:00:00 2001 From: Antonio Borneo Date: Thu, 5 Mar 2020 17:00:50 +0100 Subject: [PATCH] driver/ftdi: skip trst in swd mode When using the adapter olimex arm-jtag-swd (to convert to SWD a JTAG-only FTDI adapter), the pin trst on JTAG side is re-used to control the direction of pin SWDIO on SWD side. There is a single reset API at adapter driver to assert/deassert either srst and/or trst. A request to assert/deassert srst can cause also trst to change value, hanging the SWD communication. In SWD mode, ignore the value passed to trst. Change-Id: I5fe1eed851177d405d77ae6079da9642dc1a08f1 Signed-off-by: Antonio Borneo Reviewed-on: http://openocd.zylin.com/6006 Tested-by: jenkins --- src/jtag/drivers/ftdi.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/src/jtag/drivers/ftdi.c b/src/jtag/drivers/ftdi.c index 9d1c85cbd..9e47d3cad 100644 --- a/src/jtag/drivers/ftdi.c +++ b/src/jtag/drivers/ftdi.c @@ -524,17 +524,19 @@ static int ftdi_reset(int trst, int srst) LOG_DEBUG_IO("reset trst: %i srst %i", trst, srst); - if (trst == 1) { - if (sig_ntrst) - ftdi_set_signal(sig_ntrst, '0'); - else - LOG_ERROR("Can't assert TRST: nTRST signal is not defined"); - } else if (sig_ntrst && jtag_get_reset_config() & RESET_HAS_TRST && - trst == 0) { - if (jtag_get_reset_config() & RESET_TRST_OPEN_DRAIN) - ftdi_set_signal(sig_ntrst, 'z'); - else - ftdi_set_signal(sig_ntrst, '1'); + if (!swd_mode) { + if (trst == 1) { + if (sig_ntrst) + ftdi_set_signal(sig_ntrst, '0'); + else + LOG_ERROR("Can't assert TRST: nTRST signal is not defined"); + } else if (sig_ntrst && jtag_get_reset_config() & RESET_HAS_TRST && + trst == 0) { + if (jtag_get_reset_config() & RESET_TRST_OPEN_DRAIN) + ftdi_set_signal(sig_ntrst, 'z'); + else + ftdi_set_signal(sig_ntrst, '1'); + } } if (srst == 1) {