usb: typec: ucsi: Fix role swapping

commit eb5d7ff3cf0d55093c619b5ad107cd5c05ce8134 upstream.

All attempts to swap the roles timed out because the
completion was done without releasing the port lock. Fixing
that by releasing the lock before starting to wait for the
completion.

Link: https://lore.kernel.org/linux-usb/037de7ac-e210-bdf5-ec7a-8c0c88a0be20@gmail.com/
Fixes: ad74b8649bea ("usb: typec: ucsi: Preliminary support for alternate modes")
Cc: stable@vger.kernel.org
Reported-and-tested-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20220405134824.68067-3-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index e27a5c6fe8154e4719eab0d502eaa7de3c65bd68..8a7e2dd52ad5acff7b723be18d56b5b411feb52e 100644 (file)
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -964,14 +964,18 @@ static int ucsi_dr_swap(struct typec_port *port, enum typec_data_role role)
        if (ret < 0)
                goto out_unlock;
 
+       mutex_unlock(&con->lock);
+
        if (!wait_for_completion_timeout(&con->complete,
-                                       msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS)))
-               ret = -ETIMEDOUT;
+                                        msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS)))
+               return -ETIMEDOUT;
+
+       return 0;
 
 out_unlock:
        mutex_unlock(&con->lock);
 
-       return ret < 0 ? ret : 0;
+       return ret;
 }
 
 static int ucsi_pr_swap(struct typec_port *port, enum typec_role role)
@@ -1002,11 +1006,13 @@ static int ucsi_pr_swap(struct typec_port *port, enum typec_role role)
        if (ret < 0)
                goto out_unlock;
 
+       mutex_unlock(&con->lock);
+
        if (!wait_for_completion_timeout(&con->complete,
-                               msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS))) {
-               ret = -ETIMEDOUT;
-               goto out_unlock;
-       }
+                                        msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS)))
+               return -ETIMEDOUT;
+
+       mutex_lock(&con->lock);
 
        /* Something has gone wrong while swapping the role */
        if (UCSI_CONSTAT_PWR_OPMODE(con->status.flags) !=