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+kernel@xxxxxxxxxxxxxxx>
---
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 db739cce93ac..a72d07bdb793 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -795,11 +795,9 @@ 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));
}
--
2.20.1
