From c9aed03a0a683fd1600ea92f2ad32232d4736272 Mon Sep 17 00:00:00 2001
From: "Christian A. Ehrhardt" <lk@c--e.de>
Date: Sun, 21 Jan 2024 21:41:21 +0100
Subject: [PATCH] usb: ucsi: Add missing ppm_lock
Git-commit: c9aed03a0a683fd1600ea92f2ad32232d4736272
Patch-mainline: v6.8-rc3
References: git-fixes
Calling ->sync_write must be done while holding the PPM lock as
the mailbox logic does not support concurrent commands.
At least since the addition of partner task this means that
ucsi_acknowledge_connector_change should be called with the
PPM lock held as it calls ->sync_write.
Thus protect the only call to ucsi_acknowledge_connector_change
with the PPM. All other calls to ->sync_write already happen
under the PPM lock.
Fixes: b9aa02ca39a4 ("usb: typec: ucsi: Add polling mechanism for partner tasks like alt mode checking")
Cc: stable@vger.kernel.org
Signed-off-by: "Christian A. Ehrhardt" <lk@c--e.de>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240121204123.275441-2-lk@c--e.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/usb/typec/ucsi/ucsi.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index 5392ec698959..14f5a7bfae2e 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -938,7 +938,9 @@ static void ucsi_handle_connector_change(struct work_struct *work)
clear_bit(EVENT_PENDING, &con->ucsi->flags);
+ mutex_lock(&ucsi->ppm_lock);
ret = ucsi_acknowledge_connector_change(ucsi);
+ mutex_unlock(&ucsi->ppm_lock);
if (ret)
dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret);
--
2.35.3