]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
usb: ucsi_acpi: Fix command completion handling
authorChristian A. Ehrhardt <lk@c--e.de>
Sun, 21 Jan 2024 20:41:22 +0000 (21:41 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 23 Feb 2024 08:24:56 +0000 (09:24 +0100)
commitec68d8d25b8469882fc9c484cc6b0d88b025971e
tree080df25e4f6590b6890a94ee7cef7f798ae3ba7e
parent330d22aba17a4d30a56f007d0f51291d7e00862b
usb: ucsi_acpi: Fix command completion handling

commit 2840143e393a4ddc1caab4372969ea337371168c upstream.

In case of a spurious or otherwise delayed notification it is
possible that CCI still reports the previous completion. The
UCSI spec is aware of this and provides two completion bits in
CCI, one for normal commands and one for acks. As acks and commands
alternate the notification handler can determine if the completion
bit is from the current command.

The initial UCSI code correctly handled this but the distinction
between the two completion bits was lost with the introduction of
the new API.

To fix this revive the ACK_PENDING bit for ucsi_acpi and only complete
commands if the completion bit matches.

Fixes: f56de278e8ec ("usb: typec: ucsi: acpi: Move to the new API")
Cc: stable@vger.kernel.org
Signed-off-by: "Christian A. Ehrhardt" <lk@c--e.de>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240121204123.275441-3-lk@c--e.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/typec/ucsi/ucsi_acpi.c