usb: typec: ucsi: Resume in separate work

It can take more than one second to check each connector
when the system is resumed. So if you have, say, eight
connectors, it may take eight seconds for ucsi_resume() to
finish. That's a bit too much.

This will modify ucsi_resume() so that it schedules a work
where the interface is actually resumed instead of checking
the connectors directly. The connections will also be
checked in separate tasks which are queued for each connector
separately.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216706
Fixes: 99f6d436 ("usb: typec: ucsi: Check the connection on resume")
Cc: <stable@vger.kernel.org>
Reported-by: Todd Brandt <todd.e.brandt@intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20221123093021.25981-1-heikki.krogerus@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/ucsi/ucsi.c

@@ -1270,8 +1270,9 @@ static int ucsi_init(struct ucsi *ucsi)
 	return ret;
 }
 
-int ucsi_resume(struct ucsi *ucsi)
+static void ucsi_resume_work(struct work_struct *work)
 {
+	struct ucsi *ucsi = container_of(work, struct ucsi, resume_work);
 	struct ucsi_connector *con;
 	u64 command;
 	int ret;
@@ -1279,15 +1280,21 @@ int ucsi_resume(struct ucsi *ucsi)
 	/* Restore UCSI notification enable mask after system resume */
 	command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy;
 	ret = ucsi_send_command(ucsi, command, NULL, 0);
-	if (ret < 0)
-		return ret;
+	if (ret < 0) {
+		dev_err(ucsi->dev, "failed to re-enable notifications (%d)\n", ret);
+		return;
+	}
 
 	for (con = ucsi->connector; con->port; con++) {
 		mutex_lock(&con->lock);
-		ucsi_check_connection(con);
+		ucsi_partner_task(con, ucsi_check_connection, 1, 0);
 		mutex_unlock(&con->lock);
 	}
+}
 
+int ucsi_resume(struct ucsi *ucsi)
+{
+	queue_work(system_long_wq, &ucsi->resume_work);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(ucsi_resume);
@@ -1347,6 +1354,7 @@ struct ucsi *ucsi_create(struct device *dev, const struct ucsi_operations *ops)
 	if (!ucsi)
 		return ERR_PTR(-ENOMEM);
 
+	INIT_WORK(&ucsi->resume_work, ucsi_resume_work);
 	INIT_DELAYED_WORK(&ucsi->work, ucsi_init_work);
 	mutex_init(&ucsi->ppm_lock);
 	ucsi->dev = dev;
@@ -1401,6 +1409,7 @@ void ucsi_unregister(struct ucsi *ucsi)
 
 	/* Make sure that we are not in the middle of driver initialization */
 	cancel_delayed_work_sync(&ucsi->work);
+	cancel_work_sync(&ucsi->resume_work);
 
 	/* Disable notifications */
 	ucsi->ops->async_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));

drivers/usb/typec/ucsi/ucsi.h

@@ -287,6 +287,7 @@ struct ucsi {
 	struct ucsi_capability cap;
 	struct ucsi_connector *connector;
 
+	struct work_struct resume_work;
 	struct delayed_work work;
 	int work_count;
 #define UCSI_ROLE_SWITCH_RETRY_PER_HZ	10