i2c: ocores: set IACK bit after core is enabled

commit 5a72477 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: 18f98b1 ("[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>

Author: grembeter

drivers/i2c/busses/i2c-ocores.c

@@ -442,8 +442,8 @@ 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;
 }