From a2bd970aa62f2f7f80fd0d212b1d4ccea5df4aed Mon Sep 17 00:00:00 2001
From: Nicolas VINCENT <nicolas.vincent@vossloh.com>
Date: Wed, 23 Sep 2020 16:08:40 +0200
Subject: [PATCH] i2c: cpm: Fix i2c_ram structure
Git-commit: a2bd970aa62f2f7f80fd0d212b1d4ccea5df4aed
Patch-mainline: v5.9-rc8
References: git-fixes

the i2c_ram structure is missing the sdmatmp field mentionned in
datasheet for MPC8272 at paragraph 36.5. With this field missing, the
hardware would write past the allocated memory done through
cpm_muram_alloc for the i2c_ram structure and land in memory allocated
for the buffers descriptors corrupting the cbd_bufaddr field. Since this
field is only set during setup(), the first i2c transaction would work
and the following would send data read from an arbitrary memory
location.

Fixes: 61045dbe9d8d ("i2c: Add support for I2C bus on Freescale CPM1/CPM2 controllers")
Signed-off-by: Nicolas VINCENT <nicolas.vincent@vossloh.com>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/i2c/busses/i2c-cpm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c
index 1213e1932ccb..24d584a1c9a7 100644
--- a/drivers/i2c/busses/i2c-cpm.c
+++ b/drivers/i2c/busses/i2c-cpm.c
@@ -65,6 +65,9 @@ struct i2c_ram {
 	char    res1[4];	/* Reserved */
 	ushort  rpbase;		/* Relocation pointer */
 	char    res2[2];	/* Reserved */
+	/* The following elements are only for CPM2 */
+	char    res3[4];	/* Reserved */
+	uint    sdmatmp;	/* Internal */
 };
 
 #define I2COM_START	0x80
-- 
2.16.4