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@xxxxxxxxxxxxxxxxxxxx> Acked-by: Peter Korsgaard <peter@xxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- V1 -> V2: Added "Acked-by:", "Fixes:" and "Cc:" tags drivers/i2c/busses/i2c-ocores.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c index e106af83cef4..350ccfbe8634 100644 --- a/drivers/i2c/busses/i2c-ocores.c +++ b/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; } -- 2.43.0