Staging: echo: remove bit_operations.h

This file is no longer needed, thanks to the work done by David.

Cc: David Rowe <david@rowetel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/echo/bit_operations.h

-/*
- * SpanDSP - a series of DSP components for telephony
- *
- * bit_operations.h - Various bit level operations, such as bit reversal
- *
- * Written by Steve Underwood <steveu@coppice.org>
- *
- * Copyright (C) 2006 Steve Underwood
- *
- * All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2, as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-/*! \file */
-
-#if !defined(_BIT_OPERATIONS_H_)
-#define _BIT_OPERATIONS_H_
-
-#if defined(__i386__)  ||  defined(__x86_64__)
-/*! \brief Find the bit position of the highest set bit in a word
-    \param bits The word to be searched
-    \return The bit number of the highest set bit, or -1 if the word is zero. */
-static inline int top_bit(unsigned int bits)
-{
-	int res;
-
-	__asm__(" xorl %[res],%[res];\n"
-		" decl %[res];\n"
-		" bsrl %[bits],%[res]\n"
-		:[res] "=&r" (res)
-		:[bits] "rm"(bits)
-	);
-	return res;
-}
-
-/*! \brief Find the bit position of the lowest set bit in a word
-    \param bits The word to be searched
-    \return The bit number of the lowest set bit, or -1 if the word is zero. */
-static inline int bottom_bit(unsigned int bits)
-{
-	int res;
-
-	__asm__(" xorl %[res],%[res];\n"
-		" decl %[res];\n"
-		" bsfl %[bits],%[res]\n"
-		:[res] "=&r" (res)
-		:[bits] "rm"(bits)
-	);
-	return res;
-}
-#else
-static inline int top_bit(unsigned int bits)
-{
-	int i;
-
-	if (bits == 0)
-		return -1;
-	i = 0;
-	if (bits & 0xFFFF0000) {
-		bits &= 0xFFFF0000;
-		i += 16;
-	}
-	if (bits & 0xFF00FF00) {
-		bits &= 0xFF00FF00;
-		i += 8;
-	}
-	if (bits & 0xF0F0F0F0) {
-		bits &= 0xF0F0F0F0;
-		i += 4;
-	}
-	if (bits & 0xCCCCCCCC) {
-		bits &= 0xCCCCCCCC;
-		i += 2;
-	}
-	if (bits & 0xAAAAAAAA) {
-		bits &= 0xAAAAAAAA;
-		i += 1;
-	}
-	return i;
-}
-
-static inline int bottom_bit(unsigned int bits)
-{
-	int i;
-
-	if (bits == 0)
-		return -1;
-	i = 32;
-	if (bits & 0x0000FFFF) {
-		bits &= 0x0000FFFF;
-		i -= 16;
-	}
-	if (bits & 0x00FF00FF) {
-		bits &= 0x00FF00FF;
-		i -= 8;
-	}
-	if (bits & 0x0F0F0F0F) {
-		bits &= 0x0F0F0F0F;
-		i -= 4;
-	}
-	if (bits & 0x33333333) {
-		bits &= 0x33333333;
-		i -= 2;
-	}
-	if (bits & 0x55555555) {
-		bits &= 0x55555555;
-		i -= 1;
-	}
-	return i;
-}
-#endif
-
-/*! \brief Bit reverse a byte.
-    \param data The byte to be reversed.
-    \return The bit reversed version of data. */
-static inline uint8_t bit_reverse8(uint8_t x)
-{
-#if defined(__i386__)  ||  defined(__x86_64__)
-	/* If multiply is fast */
-	return ((x * 0x0802U & 0x22110U) | (x * 0x8020U & 0x88440U)) *
-	    0x10101U >> 16;
-#else
-	/* If multiply is slow, but we have a barrel shifter */
-	x = (x >> 4) | (x << 4);
-	x = ((x & 0xCC) >> 2) | ((x & 0x33) << 2);
-	return ((x & 0xAA) >> 1) | ((x & 0x55) << 1);
-#endif
-}
-
-/*! \brief Bit reverse a 16 bit word.
-    \param data The word to be reversed.
-    \return The bit reversed version of data. */
-uint16_t bit_reverse16(uint16_t data);
-
-/*! \brief Bit reverse a 32 bit word.
-    \param data The word to be reversed.
-    \return The bit reversed version of data. */
-uint32_t bit_reverse32(uint32_t data);
-
-/*! \brief Bit reverse each of the four bytes in a 32 bit word.
-    \param data The word to be reversed.
-    \return The bit reversed version of data. */
-uint32_t bit_reverse_4bytes(uint32_t data);
-
-/*! \brief Find the number of set bits in a 32 bit word.
-    \param x The word to be searched.
-    \return The number of set bits. */
-int one_bits32(uint32_t x);
-
-/*! \brief Create a mask as wide as the number in a 32 bit word.
-    \param x The word to be searched.
-    \return The mask. */
-uint32_t make_mask32(uint32_t x);
-
-/*! \brief Create a mask as wide as the number in a 16 bit word.
-    \param x The word to be searched.
-    \return The mask. */
-uint16_t make_mask16(uint16_t x);
-
-/*! \brief Find the least significant one in a word, and return a word
-	    with just that bit set.
-    \param x The word to be searched.
-    \return The word with the single set bit. */
-static inline uint32_t least_significant_one32(uint32_t x)
-{
-	return x & (-(int32_t) x);
-}
-
-/*! \brief Find the most significant one in a word, and return a word
-	    with just that bit set.
-    \param x The word to be searched.
-    \return The word with the single set bit. */
-static inline uint32_t most_significant_one32(uint32_t x)
-{
-#if defined(__i386__)  ||  defined(__x86_64__)
-	return 1 << top_bit(x);
-#else
-	x = make_mask32(x);
-	return x ^ (x >> 1);
-#endif
-}
-
-/*! \brief Find the parity of a byte.
-    \param x The byte to be checked.
-    \return 1 for odd, or 0 for even. */
-static inline int parity8(uint8_t x)
-{
-	x = (x ^ (x >> 4)) & 0x0F;
-	return (0x6996 >> x) & 1;
-}
-
-/*! \brief Find the parity of a 16 bit word.
-    \param x The word to be checked.
-    \return 1 for odd, or 0 for even. */
-static inline int parity16(uint16_t x)
-{
-	x ^= (x >> 8);
-	x = (x ^ (x >> 4)) & 0x0F;
-	return (0x6996 >> x) & 1;
-}
-
-/*! \brief Find the parity of a 32 bit word.
-    \param x The word to be checked.
-    \return 1 for odd, or 0 for even. */
-static inline int parity32(uint32_t x)
-{
-	x ^= (x >> 16);
-	x ^= (x >> 8);
-	x = (x ^ (x >> 4)) & 0x0F;
-	return (0x6996 >> x) & 1;
-}
-
-#endif
-/*- End of file ------------------------------------------------------------*/