ALSA: usb-audio: add support for Akai MPD16

[safe/jmp/linux-2.6] / lib / hweight.c

diff --git a/lib/hweight.c b/lib/hweight.c
index 721a4b8..3c79d50 100644 (file)
--- a/lib/hweight.c
+++ b/lib/hweight.c
@@ -1,4 +1,5 @@
 #include <linux/module.h>
+#include <linux/bitops.h>
 #include <asm/types.h>
 
 /**
@@ -8,47 +9,59 @@
  * The Hamming Weight of a number is the total number of bits set in it.
  */
 
-unsigned int hweight32(unsigned int w)
+unsigned int __sw_hweight32(unsigned int w)
 {
-       unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
+#ifdef 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 & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
-       res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
-       return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
+       res = (res + (res >> 4)) & 0x0F0F0F0F;
+       res = res + (res >> 8);
+       return (res + (res >> 16)) & 0x000000FF;
+#endif
 }
-EXPORT_SYMBOL(hweight32);
+EXPORT_SYMBOL(__sw_hweight32);
 
-unsigned int hweight16(unsigned int w)
+unsigned int __sw_hweight16(unsigned int w)
 {
-       unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
+       unsigned int res = w - ((w >> 1) & 0x5555);
        res = (res & 0x3333) + ((res >> 2) & 0x3333);
-       res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
-       return (res & 0x00FF) + ((res >> 8) & 0x00FF);
+       res = (res + (res >> 4)) & 0x0F0F;
+       return (res + (res >> 8)) & 0x00FF;
 }
-EXPORT_SYMBOL(hweight16);
+EXPORT_SYMBOL(__sw_hweight16);
 
-unsigned int hweight8(unsigned int w)
+unsigned int __sw_hweight8(unsigned int w)
 {
-       unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
+       unsigned int res = w - ((w >> 1) & 0x55);
        res = (res & 0x33) + ((res >> 2) & 0x33);
-       return (res & 0x0F) + ((res >> 4) & 0x0F);
+       return (res + (res >> 4)) & 0x0F;
 }
-EXPORT_SYMBOL(hweight8);
+EXPORT_SYMBOL(__sw_hweight8);
 
-unsigned long hweight64(__u64 w)
+unsigned long __sw_hweight64(__u64 w)
 {
 #if BITS_PER_LONG == 32
-       return hweight32((unsigned int)(w >> 32)) + hweight32((unsigned int)w);
+       return __sw_hweight32((unsigned int)(w >> 32)) +
+              __sw_hweight32((unsigned int)w);
 #elif BITS_PER_LONG == 64
-       u64 res;
-       res = (w & 0x5555555555555555ul) + ((w >> 1) & 0x5555555555555555ul);
-       res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul);
-       res = (res & 0x0F0F0F0F0F0F0F0Ful) + ((res >> 4) & 0x0F0F0F0F0F0F0F0Ful);
-       res = (res & 0x00FF00FF00FF00FFul) + ((res >> 8) & 0x00FF00FF00FF00FFul);
-       res = (res & 0x0000FFFF0000FFFFul) + ((res >> 16) & 0x0000FFFF0000FFFFul);
-       return (res & 0x00000000FFFFFFFFul) + ((res >> 32) & 0x00000000FFFFFFFFul);
+#ifdef ARCH_HAS_FAST_MULTIPLIER
+       w -= (w >> 1) & 0x5555555555555555ul;
+       w =  (w & 0x3333333333333333ul) + ((w >> 2) & 0x3333333333333333ul);
+       w =  (w + (w >> 4)) & 0x0f0f0f0f0f0f0f0ful;
+       return (w * 0x0101010101010101ul) >> 56;
 #else
-#error BITS_PER_LONG not defined
+       __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(hweight64);
+EXPORT_SYMBOL(__sw_hweight64);