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authorMark Brown <broonie@kernel.org>2022-10-19 18:37:01 +0300
committerMark Brown <broonie@kernel.org>2022-10-19 18:37:01 +0300
commit008f05a72d32dcc14038801649ec67af765fcc3c (patch)
treec958a2ab7039ea3e03621b1cbae4fcad41ee947c /include/linux/overflow.h
parent32def55d237e8507d4eb8442628fc2e59a899ea0 (diff)
parentdf496157a5afa1b6d1f4c46ad6549c2c346d1e59 (diff)
downloadlinux-008f05a72d32dcc14038801649ec67af765fcc3c.tar.xz
ASoC: jz4752b: Capture fixes
Merge series from Siarhei Volkau <lis8215@gmail.com>: The patchset fixes: - Line In path stays powered off during capturing or bypass to mixer. - incorrectly represented dB values in alsamixer, et al. - incorrect represented Capture input selector in alsamixer in Playback tab. - wrong control selected as Capture Master
Diffstat (limited to 'include/linux/overflow.h')
-rw-r--r--include/linux/overflow.h72
1 files changed, 41 insertions, 31 deletions
diff --git a/include/linux/overflow.h b/include/linux/overflow.h
index 0eb3b192f07a..19dfdd74835e 100644
--- a/include/linux/overflow.h
+++ b/include/linux/overflow.h
@@ -51,40 +51,50 @@ static inline bool __must_check __must_check_overflow(bool overflow)
return unlikely(overflow);
}
-/*
- * For simplicity and code hygiene, the fallback code below insists on
- * a, b and *d having the same type (similar to the min() and max()
- * macros), whereas gcc's type-generic overflow checkers accept
- * different types. Hence we don't just make check_add_overflow an
- * alias for __builtin_add_overflow, but add type checks similar to
- * below.
+/** check_add_overflow() - Calculate addition with overflow checking
+ *
+ * @a: first addend
+ * @b: second addend
+ * @d: pointer to store sum
+ *
+ * Returns 0 on success.
+ *
+ * *@d holds the results of the attempted addition, but is not considered
+ * "safe for use" on a non-zero return value, which indicates that the
+ * sum has overflowed or been truncated.
*/
-#define check_add_overflow(a, b, d) __must_check_overflow(({ \
- typeof(a) __a = (a); \
- typeof(b) __b = (b); \
- typeof(d) __d = (d); \
- (void) (&__a == &__b); \
- (void) (&__a == __d); \
- __builtin_add_overflow(__a, __b, __d); \
-}))
+#define check_add_overflow(a, b, d) \
+ __must_check_overflow(__builtin_add_overflow(a, b, d))
-#define check_sub_overflow(a, b, d) __must_check_overflow(({ \
- typeof(a) __a = (a); \
- typeof(b) __b = (b); \
- typeof(d) __d = (d); \
- (void) (&__a == &__b); \
- (void) (&__a == __d); \
- __builtin_sub_overflow(__a, __b, __d); \
-}))
+/** check_sub_overflow() - Calculate subtraction with overflow checking
+ *
+ * @a: minuend; value to subtract from
+ * @b: subtrahend; value to subtract from @a
+ * @d: pointer to store difference
+ *
+ * Returns 0 on success.
+ *
+ * *@d holds the results of the attempted subtraction, but is not considered
+ * "safe for use" on a non-zero return value, which indicates that the
+ * difference has underflowed or been truncated.
+ */
+#define check_sub_overflow(a, b, d) \
+ __must_check_overflow(__builtin_sub_overflow(a, b, d))
-#define check_mul_overflow(a, b, d) __must_check_overflow(({ \
- typeof(a) __a = (a); \
- typeof(b) __b = (b); \
- typeof(d) __d = (d); \
- (void) (&__a == &__b); \
- (void) (&__a == __d); \
- __builtin_mul_overflow(__a, __b, __d); \
-}))
+/** check_mul_overflow() - Calculate multiplication with overflow checking
+ *
+ * @a: first factor
+ * @b: second factor
+ * @d: pointer to store product
+ *
+ * Returns 0 on success.
+ *
+ * *@d holds the results of the attempted multiplication, but is not
+ * considered "safe for use" on a non-zero return value, which indicates
+ * that the product has overflowed or been truncated.
+ */
+#define check_mul_overflow(a, b, d) \
+ __must_check_overflow(__builtin_mul_overflow(a, b, d))
/** check_shl_overflow() - Calculate a left-shifted value and check overflow
*