This is a note to let you know that I've just added the patch titled
i2c: rcar: slave: only send STOP event when we have been addressed
to the 4.4-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-rcar-slave-only-send-stop-event-when-we-have-bee.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 4651725af4db3a35bc36d23ff6aa3be61f6a789c
Author: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Date: Mon Jun 29 17:38:07 2020 +0200
i2c: rcar: slave: only send STOP event when we have been addressed
[ Upstream commit 314139f9f0abdba61ed9a8463bbcb0bf900ac5a2 ]
When the SSR interrupt is activated, it will detect every STOP condition
on the bus, not only the ones after we have been addressed. So, enable
this interrupt only after we have been addressed, and disable it
otherwise.
Fixes: de20d1857dd6 ("i2c: rcar: add slave support")
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index dfe1a53ce4ad3..ddfb08a3e6c20 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -386,13 +386,14 @@ static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)
rcar_i2c_write(priv, ICSIER, SDR | SSR | SAR);
}
- rcar_i2c_write(priv, ICSSR, ~SAR & 0xff);
+ /* Clear SSR, too, because of old STOPs to other clients than us */
+ rcar_i2c_write(priv, ICSSR, ~(SAR | SSR) & 0xff);
}
/* master sent stop */
if (ssr_filtered & SSR) {
i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value);
- rcar_i2c_write(priv, ICSIER, SAR | SSR);
+ rcar_i2c_write(priv, ICSIER, SAR);
rcar_i2c_write(priv, ICSSR, ~SSR & 0xff);
}
@@ -541,7 +542,7 @@ static int rcar_reg_slave(struct i2c_client *slave)
priv->slave = slave;
rcar_i2c_write(priv, ICSAR, slave->addr);
rcar_i2c_write(priv, ICSSR, 0);
- rcar_i2c_write(priv, ICSIER, SAR | SSR);
+ rcar_i2c_write(priv, ICSIER, SAR);
rcar_i2c_write(priv, ICSCR, SIE | SDBS);
return 0;
