[PATCH 4.18 006/171] Input: wm97xx-ts - fix exit path

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

[ Upstream commit a3f7c3fcf60868c1e90671df5d0cf9be5900a09b ]

Loading then unloading wm97xx-ts.ko when CONFIG_AC97_BUS=m
causes a WARNING: from drivers/base/driver.c:

Unexpected driver unregister!
WARNING: CPU: 0 PID: 1709 at ../drivers/base/driver.c:193 driver_unregister+0x30/0x40

Fix this by only calling driver_unregister() with the same
condition that driver_register() is called.

Fixes: ae9d1b5fbd7b ("Input: wm97xx: add new AC97 bus support")

Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/input/touchscreen/wm97xx-core.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/input/touchscreen/wm97xx-core.c
+++ b/drivers/input/touchscreen/wm97xx-core.c
@@ -929,7 +929,8 @@ static int __init wm97xx_init(void)
 
 static void __exit wm97xx_exit(void)
 {
-	driver_unregister(&wm97xx_driver);
+	if (IS_BUILTIN(CONFIG_AC97_BUS))
+		driver_unregister(&wm97xx_driver);
 	platform_driver_unregister(&wm97xx_mfd_driver);
 }