soc/tegra: fuse: Fix bitwise vs. logical OR warning

A new warning in clang points out two instances where boolean
expressions are being used with a bitwise OR instead of logical OR:

drivers/soc/tegra/fuse/speedo-tegra20.c:72:9: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical]
                reg = tegra_fuse_read_spare(i) |
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~
                                               ||
drivers/soc/tegra/fuse/speedo-tegra20.c:72:9: note: cast one or both operands to int to silence this warning
drivers/soc/tegra/fuse/speedo-tegra20.c:87:9: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical]
                reg = tegra_fuse_read_spare(i) |
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~
                                               ||
drivers/soc/tegra/fuse/speedo-tegra20.c:87:9: note: cast one or both operands to int to silence this warning
2 warnings generated.

The motivation for the warning is that logical operations short circuit
while bitwise operations do not.

In this instance, tegra_fuse_read_spare() is not semantically returning
a boolean, it is returning a bit value. Use u32 for its return type so
that it can be used with either bitwise or boolean operators without any
warnings.

Fixes: 6f5f50b9e8aa ("ARM: tegra: Add speedo-based process identification")
Link: https://github.com/ClangBuiltLinux/linux/issues/1488
Suggested-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c
index f2151815db585b3f22bd968f0f1e984069b3b3fb..e714ed3b61bc368a7100869253657bef32da25e7 100644 (file)
--- a/drivers/soc/tegra/fuse/fuse-tegra.c
+++ b/drivers/soc/tegra/fuse/fuse-tegra.c
@@ -320,7 +320,7 @@ static struct platform_driver tegra_fuse_driver = {
 };
 builtin_platform_driver(tegra_fuse_driver);
 
-bool __init tegra_fuse_read_spare(unsigned int spare)
+u32 __init tegra_fuse_read_spare(unsigned int spare)
 {
        unsigned int offset = fuse->soc->info->spare + spare * 4;
 

diff --git a/drivers/soc/tegra/fuse/fuse.h b/drivers/soc/tegra/fuse/fuse.h
index de58feba0435015fecd06f20acdcbd911f52f464..ecff0c08e9595ace7f69deb0d99183d4ba0a6235 100644 (file)
--- a/drivers/soc/tegra/fuse/fuse.h
+++ b/drivers/soc/tegra/fuse/fuse.h
@@ -65,7 +65,7 @@ struct tegra_fuse {
 void tegra_init_revision(void);
 void tegra_init_apbmisc(void);
 
-bool __init tegra_fuse_read_spare(unsigned int spare);
+u32 __init tegra_fuse_read_spare(unsigned int spare);
 u32 __init tegra_fuse_read_early(unsigned int offset);
 
 u8 tegra_get_major_rev(void);