From 1f2735782901608656436b2b3e3a5fa9a77a441e Mon Sep 17 00:00:00 2001
From: Chris Ching <chingcodes@chromium.org>
Date: Tue, 16 Jan 2018 11:38:17 -0800
Subject: [PATCH] drivers/i2c/designware: Unset IC_ENABLE when setting target
 address

To set address on AMD, IC_ENABLE == 0.

BUG=b:69416132
BRANCH=none
TEST=Test communication with i2c TPM on grunt and coral

Change-Id: I7faee8e11439deceab946cc82d30d274b529b90d
Signed-off-by: Chris Ching <chingcodes@chromium.org>
Reviewed-on: https://review.coreboot.org/23293
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Subrata Banik <subrata.banik@intel.com>
---
 src/drivers/i2c/designware/dw_i2c.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/drivers/i2c/designware/dw_i2c.c b/src/drivers/i2c/designware/dw_i2c.c
index 384cca5783..af769ca02e 100644
--- a/src/drivers/i2c/designware/dw_i2c.c
+++ b/src/drivers/i2c/designware/dw_i2c.c
@@ -379,7 +379,11 @@ int dw_i2c_transfer(unsigned int bus,
 		}
 
 		/* Set target slave address */
-		write32(&regs->target_addr, segments->slave);
+		if (read32(&regs->target_addr) != segments->slave) {
+			dw_i2c_disable(regs);
+			write32(&regs->target_addr, segments->slave);
+			dw_i2c_enable(regs);
+		}
 
 		/* Read or write each byte in segment */
 		for (byte = 0; byte < segments->len; byte++) {