According to the reference manuals for the corresponding SoCs, SEC
frequency ratio configuration is indicated by bit 26 of the POR Device
Status Register 2. Consequently, SEC_CFG bit should be tested by mask 0x20,
not 0x80. Testing the wrong bit leads to selection of wrong I2C clock
prescaler on those SoCs.

Signed-off-by: Arseny Solokha <asolo...@kb.kras.ru>
---
 drivers/i2c/busses/i2c-mpc.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index f47916466b82..8d60db0080f6 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -332,14 +332,18 @@ static u32 mpc_i2c_get_sec_cfg_8xxx(void)
                if (prop) {
                        /*
                         * Map and check POR Device Status Register 2
-                        * (PORDEVSR2) at 0xE0014
+                        * (PORDEVSR2) at 0xE0014. Note than while MPC8533
+                        * and MPC8544 indicate SEC frequency ratio
+                        * configuration as bit 26 in PORDEVSR2, other MPC8xxx
+                        * parts may store it differently or may not have it
+                        * at all.
                         */
                        reg = ioremap(get_immrbase() + *prop + 0x14, 0x4);
                        if (!reg)
                                printk(KERN_ERR
                                       "Error: couldn't map PORDEVSR2\n");
                        else
-                               val = in_be32(reg) & 0x00000080; /* sec-cfg */
+                               val = in_be32(reg) & 0x00000020; /* sec-cfg */
                        iounmap(reg);
                }
        }
-- 
2.15.0

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