From a238031d0240a4780a0942dec152c4e8b1a37b0b Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Sun, 8 Dec 2019 22:11:40 +0100 Subject: [PATCH] media: v4l2-device.h: Explicitly compare grp{id,mask} to zero in v4l2_device macros [ Upstream commit afb34781620274236bd9fc9246e22f6963ef5262 ] When building with Clang + -Wtautological-constant-compare, several of the ivtv and cx18 drivers warn along the lines of: drivers/media/pci/cx18/cx18-driver.c:1005:21: warning: converting the result of '<<' to a boolean always evaluates to true [-Wtautological-constant-compare] cx18_call_hw(cx, CX18_HW_GPIO_RESET_CTRL, ^ drivers/media/pci/cx18/cx18-cards.h:18:37: note: expanded from macro 'CX18_HW_GPIO_RESET_CTRL' #define CX18_HW_GPIO_RESET_CTRL (1 << 6) ^ 1 warning generated. This warning happens because the shift operation is implicitly converted to a boolean in v4l2_device_mask_call_all before being negated. This can be solved by just comparing the mask result to 0 explicitly so that there is no boolean conversion. The ultimate goal is to enable -Wtautological-compare globally because there are several subwarnings that would be helpful to have. For visual consistency and avoidance of these warnings in the future, all of the implicitly boolean conversions in the v4l2_device macros are converted to explicit ones as well. Link: https://github.com/ClangBuiltLinux/linux/issues/752 Reviewed-by: Ezequiel Garcia Reviewed-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- include/media/v4l2-device.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h index b330e4a08a6b..40840fec337c 100644 --- a/include/media/v4l2-device.h +++ b/include/media/v4l2-device.h @@ -372,7 +372,7 @@ static inline void v4l2_subdev_notify(struct v4l2_subdev *sd, struct v4l2_subdev *__sd; \ \ __v4l2_device_call_subdevs_p(v4l2_dev, __sd, \ - !(grpid) || __sd->grp_id == (grpid), o, f , \ + (grpid) == 0 || __sd->grp_id == (grpid), o, f , \ ##args); \ } while (0) @@ -404,7 +404,7 @@ static inline void v4l2_subdev_notify(struct v4l2_subdev *sd, ({ \ struct v4l2_subdev *__sd; \ __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, \ - !(grpid) || __sd->grp_id == (grpid), o, f , \ + (grpid) == 0 || __sd->grp_id == (grpid), o, f , \ ##args); \ }) @@ -432,8 +432,8 @@ static inline void v4l2_subdev_notify(struct v4l2_subdev *sd, struct v4l2_subdev *__sd; \ \ __v4l2_device_call_subdevs_p(v4l2_dev, __sd, \ - !(grpmsk) || (__sd->grp_id & (grpmsk)), o, f , \ - ##args); \ + (grpmsk) == 0 || (__sd->grp_id & (grpmsk)), o, \ + f , ##args); \ } while (0) /** @@ -463,8 +463,8 @@ static inline void v4l2_subdev_notify(struct v4l2_subdev *sd, ({ \ struct v4l2_subdev *__sd; \ __v4l2_device_call_subdevs_until_err_p(v4l2_dev, __sd, \ - !(grpmsk) || (__sd->grp_id & (grpmsk)), o, f , \ - ##args); \ + (grpmsk) == 0 || (__sd->grp_id & (grpmsk)), o, \ + f , ##args); \ })