The device_for_each_child() doesn't require the returned value to be checked. Thus, drop the dummy variable completely and have no warning anymore: drivers/spi/spi.c: In function ‘spi_unregister_controller’: drivers/spi/spi.c:2480:6: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable] int dummy; ^~~~~ Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> --- drivers/spi/spi.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 82063d2e4f36..caaae376d54e 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2477,7 +2477,6 @@ void spi_unregister_controller(struct spi_controller *ctlr) { struct spi_controller *found; int id = ctlr->bus_num; - int dummy; /* First make sure that this controller was ever added */ mutex_lock(&board_lock); @@ -2491,7 +2490,7 @@ void spi_unregister_controller(struct spi_controller *ctlr) list_del(&ctlr->list); mutex_unlock(&board_lock); - dummy = device_for_each_child(&ctlr->dev, NULL, __unregister); + device_for_each_child(&ctlr->dev, NULL, __unregister); device_unregister(&ctlr->dev); /* free bus id */ mutex_lock(&board_lock); -- 2.20.1