The driver uses kzalloc and kfree functions. So it should include linux/slab.h. This header file is implicitly included by v4l2-common.h if CONFIG_SPI is enabled. But when it is disabled, slab.h is not included. In this case, the driver does not compile: drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c: In function ‘mtk_jpeg_open’: drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c:1017:8: error: implicit declaration of function ‘kzalloc’ [-Werror=implicit-function-declaration] ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); ^~~~~~~ drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c:1017:6: warning: assignment makes pointer from integer without a cast [-Wint-conversion] ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); ^ drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c:1047:2: error: implicit declaration of function ‘kfree’ [-Werror=implicit-function-declaration] kfree(ctx); ^~~~~ This patch adds the missing include to fix this issue. Signed-off-by: Jérémy Lefaure <jeremy.lefaure@xxxxxxxxxxxx> --- drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c b/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c index b10183f7942b..f9bd58ce7d32 100644 --- a/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c +++ b/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c @@ -22,6 +22,7 @@ #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> +#include <linux/slab.h> #include <linux/spinlock.h> #include <media/v4l2-event.h> #include <media/v4l2-mem2mem.h> -- 2.12.0