[PATCH v2 1/3] soundwire: bus: Don't unassign dev_num before unregistering device

[Charles Keepax <ckeepax@opensource.cirrus.com>]

Don't mark dev_num as unassigned until after the driver remove has
been called. The driver may want to communicate with the device
as part of the driver remove operation, so the dev_num should
remain assigned until that has completed. This requires moving from
device_unregister() to manually calling device_del() and device_put()
to ensure that the slave struct isn't freed too early.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

Changes since v1:
 - Split device_unregister into device_del and put_device

 drivers/soundwire/bus.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index aeaae5a57c89d..1488b6540844c 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -175,8 +175,9 @@ static int sdw_delete_slave(struct device *dev, void *data)
 
 	sdw_slave_debugfs_exit(slave);
 
-	mutex_lock(&bus->bus_lock);
+	device_del(dev);
 
+	mutex_lock(&bus->bus_lock);
 	if (slave->dev_num) { /* clear dev_num if assigned */
 		clear_bit(slave->dev_num, bus->assigned);
 		if (bus->ops && bus->ops->put_device_num)
@@ -185,7 +186,8 @@ static int sdw_delete_slave(struct device *dev, void *data)
 	list_del_init(&slave->node);
 	mutex_unlock(&bus->bus_lock);
 
-	device_unregister(dev);
+	put_device(dev);
+
 	return 0;
 }
 
-- 
2.47.3