This is a note to let you know that I've just added the patch titled
usb: typec: ucsi: Clear pending after acking connector change
to the 5.10-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:
usb-typec-ucsi-clear-pending-after-acking-connector-change.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8c9b3caab3ac26db1da00b8117901640c55a69dd Mon Sep 17 00:00:00 2001
From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Date: Sat, 15 May 2021 21:09:53 -0700
Subject: usb: typec: ucsi: Clear pending after acking connector change
From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
commit 8c9b3caab3ac26db1da00b8117901640c55a69dd upstream.
It's possible that the interrupt handler for the UCSI driver signals a
connector changes after the handler clears the PENDING bit, but before
it has sent the acknowledge request. The result is that the handler is
invoked yet again, to ack the same connector change.
At least some versions of the Qualcomm UCSI firmware will not handle the
second - "spurious" - acknowledgment gracefully. So make sure to not
clear the pending flag until the change is acknowledged.
Any connector changes coming in after the acknowledgment, that would
have the pending flag incorrectly cleared, would afaict be covered by
the subsequent connector status check.
Fixes: 217504a05532 ("usb: typec: ucsi: Work around PPM losing change information")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Acked-By: Benjamin Berg <bberg@xxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210516040953.622409-1-bjorn.andersson@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/typec/ucsi/ucsi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -703,8 +703,8 @@ static void ucsi_handle_connector_change
ucsi_send_command(con->ucsi, command, NULL, 0);
/* 3. ACK connector change */
- clear_bit(EVENT_PENDING, &ucsi->flags);
ret = ucsi_acknowledge_connector_change(ucsi);
+ clear_bit(EVENT_PENDING, &ucsi->flags);
if (ret) {
dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret);
goto out_unlock;
Patches currently in stable-queue which might be from bjorn.andersson@xxxxxxxxxx are
queue-5.10/cpufreq-blocklist-qualcomm-sm8150-in-cpufreq-dt-plat.patch
queue-5.10/arm64-dts-qcom-msm8994-angler-fix-gpio-reserved-ranges-85-88.patch
queue-5.10/usb-typec-ucsi-clear-pending-after-acking-connector-change.patch
