New patch to review for coreboot: 76c6cf6 tpm: i2c: When probing the TPM, write a 0 into the TPM access register.

[Isaac Christensen]

Isaac Christensen ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/7007

-gerrit

commit 76c6cf6052a22283b71d5abffe120bb34acfc163
Author: Gabe Black 
Date:   Wed Mar 26 21:51:41 2014 -0700

tpm: i2c: When probing the TPM, write a 0 into the TPM access register.

Not doing so makes it fail when run at high frequency.

Change-Id: I1cfb69c55f03cb90f66f437289803d897a1aad5c
    Signed-off-by: Gabe Black 
    Reviewed-on: https://chromium-review.googlesource.com/191812
    Reviewed-by: Tom Warren 
    Reviewed-by: Jimmy Zhang 
    Reviewed-by: David Hendricks 
    Tested-by: Tom Warren 
    Commit-Queue: Gabe Black 
    (cherry picked from commit 04452441d2bfe2cacd3e0b6990c0e9261b5350d1)
    Signed-off-by: Isaac Christensen 
---
 src/drivers/i2c/tpm/tis.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/drivers/i2c/tpm/tis.c b/src/drivers/i2c/tpm/tis.c
index 3a5f519..e8d69ac 100644
--- a/src/drivers/i2c/tpm/tis.c
+++ b/src/drivers/i2c/tpm/tis.c
@@ -79,10 +79,10 @@ int tis_init(void)
     * Probe TPM twice; the first probing might fail because TPM is asleep,
     * and the probing can wake up TPM.
     */
-	uint8_t tmp;
+	uint8_t tmp = 0;

-	if (i2c_read(bus, chip, 0, 0, &tmp, sizeof(tmp)) &&
-			i2c_read(bus, chip, 0, 0, &tmp, sizeof(tmp)))
+	if (i2c_write(bus, chip, 0, 1, &tmp, sizeof(tmp)) &&
+			i2c_write(bus, chip, 0, 1, &tmp, sizeof(tmp)))
    	return -1;

return 0;