i2c: ocores: set IACK bit after core is enabled

commit 5a72477273066b5b357801ab2d315ef14949d402 upstream.

Setting IACK bit when core is disabled does not clear the "Interrupt Flag"
bit in the status register, and the interrupt remains pending.

Sometimes it causes failure for the very first message transfer, that is
usually a device probe.

Hence, set IACK bit after core is enabled to clear pending interrupt.

Fixes: 18f98b1e3147 ("[PATCH] i2c: New bus driver for the OpenCores I2C controller")
Signed-off-by: Grygorii Tertychnyi <grygorii.tertychnyi@leica-geosystems.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index 1c3595c8a761a8d92c5f21f3d6a6c6a4aa471a5e..f107a512210fade10538379fc2c37a0e566587c4 100644 (file)
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -443,8 +443,8 @@ static int ocores_init(struct device *dev, struct ocores_i2c *i2c)
        oc_setreg(i2c, OCI2C_PREHIGH, prescale >> 8);
 
        /* Init the device */
-       oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK);
        oc_setreg(i2c, OCI2C_CONTROL, ctrl | OCI2C_CTRL_EN);
+       oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK);
 
        return 0;
 }