[PATCH 3.8 45/67] VME: Correct read/write alignment algorithm

[Kamal Mostafa]

3.8.13.19 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Martyn Welch <martyn.welch at ge.com>

commit f0342e66b397947ed8c3eef8c37b5ca2d5b1bb50 upstream.

In order to ensure the correct width cycles on the VME bus, the VME bridge
drivers implement an algorithm to utilise the largest possible width reads and
writes whilst maintaining natural alignment constraints. The algorithm
currently looks at the start address rather than the current read/write address
when determining whether a 16-bit width cycle is required to get to 32-bit
alignment.  This results in incorrect alignment,

Reported-by: Jim Strouth <james.strouth at ge.com>
Tested-by: Jim Strouth <james.strouth at ge.com>
Signed-off-by: Martyn Welch <martyn.welch at ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/vme/bridges/vme_ca91cx42.c | 4 ++--
 drivers/vme/bridges/vme_tsi148.c   | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/vme/bridges/vme_ca91cx42.c b/drivers/vme/bridges/vme_ca91cx42.c
index 64bfea3..8ca1030 100644
--- a/drivers/vme/bridges/vme_ca91cx42.c
+++ b/drivers/vme/bridges/vme_ca91cx42.c
@@ -880,7 +880,7 @@ static ssize_t ca91cx42_master_read(struct vme_master_resource *image,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			*(u8 *)(buf + done) = ioread8(addr + done);
 			done += 1;
@@ -934,7 +934,7 @@ static ssize_t ca91cx42_master_write(struct vme_master_resource *image,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			iowrite8(*(u8 *)(buf + done), addr + done);
 			done += 1;
diff --git a/drivers/vme/bridges/vme_tsi148.c b/drivers/vme/bridges/vme_tsi148.c
index 9c1aa4d..6342406 100644
--- a/drivers/vme/bridges/vme_tsi148.c
+++ b/drivers/vme/bridges/vme_tsi148.c
@@ -1283,7 +1283,7 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			*(u8 *)(buf + done) = ioread8(addr + done);
 			done += 1;
@@ -1365,7 +1365,7 @@ static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			iowrite8(*(u8 *)(buf + done), addr + done);
 			done += 1;
-- 
1.8.3.2