Clang-8 evaluates both sides of a ?: expression to check for
valid arithmetic even in the side that is never taken. This
results in a build warning:
drivers/spi/spi-sh-msiof.c:1052:24: error: shift count >= width of type
[-Werror,-Wshift-count-overflow]
.bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32),
^~~~~~~~~~~~~~~~~~~~~~~~~
Change the implementation to use the GENMASK() macro that does
what we want here but does not have a problem with the shift
count overflow.
Link: https://bugs.llvm.org/show_bug.cgi?id=38789
Signed-off-by: Arnd Bergmann <[email protected]>
---
v3: use GENMASK() instead of open-coding it
v2: add a code comment
---
include/linux/spi/spi.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 662b336aa2e4..b27386450089 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -444,8 +444,7 @@ struct spi_controller {
/* bitmask of supported bits_per_word for transfers */
u32 bits_per_word_mask;
#define SPI_BPW_MASK(bits) BIT((bits) - 1)
-#define SPI_BIT_MASK(bits) (((bits) == 32) ? ~0U : (BIT(bits) - 1))
-#define SPI_BPW_RANGE_MASK(min, max) (SPI_BIT_MASK(max) - SPI_BIT_MASK(min -
1))
+#define SPI_BPW_RANGE_MASK(min, max) GENMASK((min) - 1, (max) - 1)
/* limits on transfer speed */
u32 min_speed_hz;
--
2.20.0
