rtc: BCD codeshrink (d3de851a) · Commits · 戴 / test

This updates <linux/bcd.h> to define the key routines as constant functions, which the macros will then call. Newer code can now call bcd2bin() instead of SCREAMING BCD2BIN() TO THE FOUR WINDS. This lets each driver shrink their codespace by using N function calls to a single (global) copy of those routines, instead of N inlined copies of these functions per driver. These routines aren't used in speed-critical code. Almost all callers are in the RTC framework. Typical per-driver savings is near 300 bytes. Signed-off-by:

David Brownell <dbrownell@users.sourceforge.net> Acked-by:

Adrian Bunk <bunk@kernel.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

include/linux/bcd.h

+7 −2

Original line number	Diff line number	Diff line
		@@ -10,8 +10,13 @@
		#ifndef _BCD_H
		#define _BCD_H

		#define BCD2BIN(val) (((val) & 0x0f) + ((val)>>4)*10)
		#define BIN2BCD(val) ((((val)/10)<<4) + (val)%10)
		#include <linux/compiler.h>

		unsigned bcd2bin(unsigned char val) __attribute_const__;
		unsigned char bin2bcd(unsigned val) __attribute_const__;

		#define BCD2BIN(val) bcd2bin(val)
		#define BIN2BCD(val) bin2bcd(val)

		/* backwards compat */
		#define BCD_TO_BIN(val) ((val)=BCD2BIN(val))

lib/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -18,7 +18,7 @@ lib-$(CONFIG_SMP) += cpumask.o

		lib-y += kobject.o kref.o klist.o

		obj-y += div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
		obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
		bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o

		ifeq ($(CONFIG_DEBUG_KOBJECT),y)

lib/bcd.c

0 → 100644

+14 −0

Original line number	Diff line number	Diff line
		#include <linux/bcd.h>
		#include <linux/module.h>

		unsigned bcd2bin(unsigned char val)
		{
		return (val & 0x0f) + (val >> 4) * 10;
		}
		EXPORT_SYMBOL(bcd2bin);

		unsigned char bin2bcd(unsigned val)
		{
		return ((val / 10) << 4) + val % 10;
		}
		EXPORT_SYMBOL(bin2bcd);

Admin message