Commit 99a97a8b authored Apr 02, 2017 by Adam Borowski Committed by Ben Skeggs Apr 06, 2017

drm/nouveau/gpio: enable interrupts on cards with 32 gpio lines



The code attempts to enable them, but hits an undefined behaviour by
shifting by the entire register's width:

    int lines = 32;
    u32 mask = (1 << lines) - 1;    // 00000000 on x86
    u32 mask = (1 << lines) - 1;    // ffffffff on arm (32)
    u32 mask = (1 << lines) - 1;    // 00000000 on arm64
    u32 mask = (1ULL << lines) - 1; // ffffffff everywhere

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

parent b2c4ef70

drivers/gpu/drm/nouveau/nvkm/subdev/gpio/base.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -164,7 +164,7 @@ static int
		nvkm_gpio_fini(struct nvkm_subdev *subdev, bool suspend)
		{
		struct nvkm_gpio *gpio = nvkm_gpio(subdev);
		u32 mask = (1 << gpio->func->lines) - 1;
		u32 mask = (1ULL << gpio->func->lines) - 1;

		gpio->func->intr_mask(gpio, NVKM_GPIO_TOGGLED, mask, 0);
		gpio->func->intr_stat(gpio, &mask, &mask);