From ab1e59b4dc0370734ab3afb8de0c10a6f5a211ad Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Thu, 8 May 2014 18:24:55 -0700 Subject: [PATCH] backlight: gpio-backlight: Fix warning when the GPIO is on a I2C chip If the GPIO for the backlight is on an I2C chip, we currently get nasty warnings like this during the boot: WARNING: CPU: 0 PID: 6 at drivers/gpio/gpiolib.c:2364 gpiod_set_raw_value+0x40/0x4c() Modules linked in: CPU: 0 PID: 6 Comm: kworker/u2:0 Not tainted 3.15.0-rc4-12393-gcde9f4e #400 Workqueue: deferwq deferred_probe_work_func [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) from [] (dump_stack+0x80/0x9c) [] (dump_stack) from [] (warn_slowpath_common+0x68/0x8c) [] (warn_slowpath_common) from [] (warn_slowpath_null+0x1c/0x24) [] (warn_slowpath_null) from [] (gpiod_set_raw_value+0x40/0x4c) [] (gpiod_set_raw_value) from [] (gpio_backlight_update_status+0x4c/0x74) [] (gpio_backlight_update_status) from [] (gpio_backlight_probe+0x168/0x254) [] (gpio_backlight_probe) from [] (platform_drv_probe+0x18/0x48) [] (platform_drv_probe) from [] (driver_probe_device+0x10c/0x238) [] (driver_probe_device) from [] (bus_for_each_drv+0x44/0x8c) [] (bus_for_each_drv) from [] (device_attach+0x74/0x8c) [] (device_attach) from [] (bus_probe_device+0x88/0xb0) [] (bus_probe_device) from [] (deferred_probe_work_func+0x64/0x94) [] (deferred_probe_work_func) from [] (process_one_work+0x1b4/0x4bc) [] (process_one_work) from [] (worker_thread+0x11c/0x398) [] (worker_thread) from [] (kthread+0xc8/0xe4) [] (kthread) from [] (ret_from_fork+0x14/0x2c) Fix this by using gpio_set_value_cansleep() as suggested in drivers/gpio/gpiolib.c:2364. This is what the other backlight drivers are also doing. Signed-off-by: Tony Lindgren Acked-by: Jingoo Han Signed-off-by: Lee Jones --- drivers/video/backlight/gpio_backlight.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c index a2eba12..1cea688 100644 --- a/drivers/video/backlight/gpio_backlight.c +++ b/drivers/video/backlight/gpio_backlight.c @@ -38,7 +38,8 @@ static int gpio_backlight_update_status(struct backlight_device *bl) bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK)) brightness = 0; - gpio_set_value(gbl->gpio, brightness ? gbl->active : !gbl->active); + gpio_set_value_cansleep(gbl->gpio, + brightness ? gbl->active : !gbl->active); return 0; } -- 2.7.4