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Revision 4e68af0b0694ac5f16d0c61a7682aa2d46348454 authored by Linus Torvalds on 27 October 2016, 22:06:29 UTC, committed by Linus Torvalds on 27 October 2016, 22:06:29 UTC 
Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
 
Pull i2c fixes from Wolfram Sang:
 "I2C has some driver bugfixes, module autoload fixes, and driver
  enablement on some architectures"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: imx: defer probe if bus recovery GPIOs are not ready
  i2c: designware: Avoid aborted transfers with fast reacting I2C slaves
  i2c: i801: Fix I2C Block Read on 8-Series/C220 and later
  i2c: xgene: Avoid dma_buffer overrun
  i2c: digicolor: Fix module autoload
  i2c: xlr: Fix module autoload for OF registration
  i2c: xlp9xx: Fix module autoload
  i2c: jz4780: Fix module autoload
  i2c: allow configuration of imx driver for ColdFire architecture
  i2c: mark device nodes only in case of successful instantiation
  i2c: rk3x: Give the tuning value 0 during rk3x_i2c_v0_calc_timings
  i2c: hix5hd2: allow build with ARCH_HISI
2 parent s 7f2145b + 533169d
Raw File
hweight.c 
#include <linux/export.h>
#include <linux/bitops.h>
#include <asm/types.h>

/**
 * hweightN - returns the hamming weight of a N-bit word
 * @x: the word to weigh
 *
 * The Hamming Weight of a number is the total number of bits set in it.
 */

#ifndef __HAVE_ARCH_SW_HWEIGHT
unsigned int __sw_hweight32(unsigned int w)
{
#ifdef CONFIG_ARCH_HAS_FAST_MULTIPLIER
	w -= (w >> 1) & 0x55555555;
	w =  (w & 0x33333333) + ((w >> 2) & 0x33333333);
	w =  (w + (w >> 4)) & 0x0f0f0f0f;
	return (w * 0x01010101) >> 24;
#else
	unsigned int res = w - ((w >> 1) & 0x55555555);
	res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
	res = (res + (res >> 4)) & 0x0F0F0F0F;
	res = res + (res >> 8);
	return (res + (res >> 16)) & 0x000000FF;
#endif
}
EXPORT_SYMBOL(__sw_hweight32);
#endif

unsigned int __sw_hweight16(unsigned int w)
{
	unsigned int res = w - ((w >> 1) & 0x5555);
	res = (res & 0x3333) + ((res >> 2) & 0x3333);
	res = (res + (res >> 4)) & 0x0F0F;
	return (res + (res >> 8)) & 0x00FF;
}
EXPORT_SYMBOL(__sw_hweight16);

unsigned int __sw_hweight8(unsigned int w)
{
	unsigned int res = w - ((w >> 1) & 0x55);
	res = (res & 0x33) + ((res >> 2) & 0x33);
	return (res + (res >> 4)) & 0x0F;
}
EXPORT_SYMBOL(__sw_hweight8);

#ifndef __HAVE_ARCH_SW_HWEIGHT
unsigned long __sw_hweight64(__u64 w)
{
#if BITS_PER_LONG == 32
	return __sw_hweight32((unsigned int)(w >> 32)) +
	       __sw_hweight32((unsigned int)w);
#elif BITS_PER_LONG == 64
#ifdef CONFIG_ARCH_HAS_FAST_MULTIPLIER
	w -= (w >> 1) & 0x5555555555555555ul;
	w =  (w & 0x3333333333333333ul) + ((w >> 2) & 0x3333333333333333ul);
	w =  (w + (w >> 4)) & 0x0f0f0f0f0f0f0f0ful;
	return (w * 0x0101010101010101ul) >> 56;
#else
	__u64 res = w - ((w >> 1) & 0x5555555555555555ul);
	res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul);
	res = (res + (res >> 4)) & 0x0F0F0F0F0F0F0F0Ful;
	res = res + (res >> 8);
	res = res + (res >> 16);
	return (res + (res >> 32)) & 0x00000000000000FFul;
#endif
#endif
}
EXPORT_SYMBOL(__sw_hweight64);
#endif
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