From: Marcin Obara <marcin_obara@users.sourceforge.net>
Date: Thu, 16 Oct 2008 05:04:34 +0000 (-0700)
Subject: tpm: correct tpm timeouts to jiffies conversion
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=9e5b1b12226d5a501fbc6706ca090e00d18a01ad;p=openwrt%2Fstaging%2Fblogic.git

tpm: correct tpm timeouts to jiffies conversion

This patch fixes timeouts conversion to jiffies, by replacing
msecs_to_jiffies() calls with usecs_to_jiffies().  According to TCG TPM
Specification Version 1.2 Revision 103 (pages 166, 167) TPM timeouts and
durations are returned in microseconds (usec) not in miliseconds (msec).

This fixes a long hang while loading TPM driver, if TPM chip starts in
"Idle" state instead of "Ready" state.  Without this patch - 'modprobe'
may hang for 30 seconds or more.

Signed-off-by: Marcin Obara <marcin_obara@users.sourceforge.net>
Cc: Marcel Selhorst <tpm@selhorst.net>
Cc: Kylene Jo Hall <kjhall@us.ibm.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 1fee7034a386..6b5a0e0127a7 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -525,19 +525,19 @@ void tpm_get_timeouts(struct tpm_chip *chip)
 	timeout =
 	    be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX)));
 	if (timeout)
-		chip->vendor.timeout_a = msecs_to_jiffies(timeout);
+		chip->vendor.timeout_a = usecs_to_jiffies(timeout);
 	timeout =
 	    be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_2_IDX)));
 	if (timeout)
-		chip->vendor.timeout_b = msecs_to_jiffies(timeout);
+		chip->vendor.timeout_b = usecs_to_jiffies(timeout);
 	timeout =
 	    be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_3_IDX)));
 	if (timeout)
-		chip->vendor.timeout_c = msecs_to_jiffies(timeout);
+		chip->vendor.timeout_c = usecs_to_jiffies(timeout);
 	timeout =
 	    be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_4_IDX)));
 	if (timeout)
-		chip->vendor.timeout_d = msecs_to_jiffies(timeout);
+		chip->vendor.timeout_d = usecs_to_jiffies(timeout);
 
 duration:
 	memcpy(data, tpm_cap, sizeof(tpm_cap));
@@ -554,15 +554,15 @@ duration:
 		return;
 
 	chip->vendor.duration[TPM_SHORT] =
-	    msecs_to_jiffies(be32_to_cpu
+	    usecs_to_jiffies(be32_to_cpu
 			     (*((__be32 *) (data +
 					    TPM_GET_CAP_RET_UINT32_1_IDX))));
 	chip->vendor.duration[TPM_MEDIUM] =
-	    msecs_to_jiffies(be32_to_cpu
+	    usecs_to_jiffies(be32_to_cpu
 			     (*((__be32 *) (data +
 					    TPM_GET_CAP_RET_UINT32_2_IDX))));
 	chip->vendor.duration[TPM_LONG] =
-	    msecs_to_jiffies(be32_to_cpu
+	    usecs_to_jiffies(be32_to_cpu
 			     (*((__be32 *) (data +
 					    TPM_GET_CAP_RET_UINT32_3_IDX))));
 }