From: Russell King <rmk+ker...@armlinux.org.uk>

[ Upstream commit e81c979f4e071d516aa27cf5a0c3939da00dc1ca ]

If we timeout during a message transfer, the control register may
contain bits that cause an action to be set. Read-modify-writing the
register leaving these bits set may trigger the hardware to attempt
one of these actions unintentionally.

Always clear these bits when cleaning up after a message or after
a timeout.

Signed-off-by: Russell King <rmk+ker...@armlinux.org.uk>
Signed-off-by: Wolfram Sang <w...@kernel.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/i2c/busses/i2c-pxa.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 466e4f681d7a..30a6e07212a4 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -747,11 +747,9 @@ static inline void i2c_pxa_stop_message(struct pxa_i2c 
*i2c)
 {
        u32 icr;
 
-       /*
-        * Clear the STOP and ACK flags
-        */
+       /* Clear the START, STOP, ACK, TB and MA flags */
        icr = readl(_ICR(i2c));
-       icr &= ~(ICR_STOP | ICR_ACKNAK);
+       icr &= ~(ICR_START | ICR_STOP | ICR_ACKNAK | ICR_TB | ICR_MA);
        writel(icr, _ICR(i2c));
 }
 
-- 
2.25.1

Reply via email to