X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fstaging%2Fecho%2Fbit_operations.h;h=cecdcf3fd755ab640d602ce6aebde0e1273b2c43;hb=45432371b448c80622d8069b845625996127caeb;hp=b32f4bf993970f4d58e1951640a63500b3715162;hpb=72558dde738b06cc01e16b3247a9659ca739e22d;p=linux-2.6-omap-h63xx.git diff --git a/drivers/staging/echo/bit_operations.h b/drivers/staging/echo/bit_operations.h index b32f4bf9939..cecdcf3fd75 100644 --- a/drivers/staging/echo/bit_operations.h +++ b/drivers/staging/echo/bit_operations.h @@ -30,114 +30,98 @@ #if !defined(_BIT_OPERATIONS_H_) #define _BIT_OPERATIONS_H_ -#ifdef __cplusplus -extern "C" { -#endif - #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; + int res; + + __asm__(" xorl %[res],%[res];\n" + " decl %[res];\n" + " bsrl %[bits],%[res]\n" + :[res] "=&r" (res) + :[bits] "rm"(bits) + ); + return res; } -/*- End of function --------------------------------------------------------*/ /*! \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; + int res; + + __asm__(" xorl %[res],%[res];\n" + " decl %[res];\n" + " bsfl %[bits],%[res]\n" + :[res] "=&r" (res) + :[bits] "rm"(bits) + ); + return res; } -/*- End of function --------------------------------------------------------*/ #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; + 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; } -/*- End of function --------------------------------------------------------*/ 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; + 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; } -/*- End of function --------------------------------------------------------*/ #endif /*! \brief Bit reverse a byte. @@ -146,16 +130,16 @@ static __inline__ int bottom_bit(unsigned int bits) 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; + /* 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); + /* 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 } -/*- End of function --------------------------------------------------------*/ /*! \brief Bit reverse a 16 bit word. \param data The word to be reversed. @@ -193,9 +177,8 @@ uint16_t make_mask16(uint16_t x); \return The word with the single set bit. */ static __inline__ uint32_t least_significant_one32(uint32_t x) { - return (x & (-(int32_t) x)); + return (x & (-(int32_t) x)); } -/*- End of function --------------------------------------------------------*/ /*! \brief Find the most significant one in a word, and return a word with just that bit set. @@ -204,50 +187,42 @@ static __inline__ uint32_t least_significant_one32(uint32_t x) static __inline__ uint32_t most_significant_one32(uint32_t x) { #if defined(__i386__) || defined(__x86_64__) - return 1 << top_bit(x); + return 1 << top_bit(x); #else - x = make_mask32(x); - return (x ^ (x >> 1)); + x = make_mask32(x); + return (x ^ (x >> 1)); #endif } -/*- End of function --------------------------------------------------------*/ /*! \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; + x = (x ^ (x >> 4)) & 0x0F; + return (0x6996 >> x) & 1; } -/*- End of function --------------------------------------------------------*/ /*! \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; + x ^= (x >> 8); + x = (x ^ (x >> 4)) & 0x0F; + return (0x6996 >> x) & 1; } -/*- End of function --------------------------------------------------------*/ /*! \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; + x ^= (x >> 16); + x ^= (x >> 8); + x = (x ^ (x >> 4)) & 0x0F; + return (0x6996 >> x) & 1; } -/*- End of function --------------------------------------------------------*/ - -#ifdef __cplusplus -} -#endif #endif /*- End of file ------------------------------------------------------------*/