This is a note to let you know that I've just added the patch titled
i2c: ocores: set IACK bit after core is enabled
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
i2c-ocores-set-iack-bit-after-core-is-enabled.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 99bc9c04c215ee00533b69200ee5c59b2a93871b
Author: Grygorii Tertychnyi <grembeter@xxxxxxxxx>
Date: Mon May 20 17:39:32 2024 +0200
i2c: ocores: set IACK bit after core is enabled
[ Upstream commit 5a72477273066b5b357801ab2d315ef14949d402 ]
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
Signed-off-by: Andi Shyti <andi.shyti@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index aa852028d8c15..7646d6c99179b 100644
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -290,8 +290,8 @@ 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_IEN | OCI2C_CTRL_EN);
+ oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK);
return 0;
}
