lib: isolate rational fractions helper function

Provide a helper function to determine optimum numerator
denominator value pairs taking into account restricted
register size. Useful especially with PLL and other clock
configurations.

Signed-off-by: Oskar Schirmer <os@emlix.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index 8ade0a7a91e0..9960be04cbbe 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -10,6 +10,9 @@ menu "Library routines"
 config BITREVERSE
         tristate
 
+config RATIONAL
+        boolean
+
 config GENERIC_FIND_FIRST_BIT
         bool