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authorJohn W. Linville <linville@tuxdriver.com>2011-06-08 13:44:21 -0400
committerJohn W. Linville <linville@tuxdriver.com>2011-06-08 13:44:21 -0400
commitc0c33addcba2ce753b4e2746db99feaae2f82a85 (patch)
treedab480183ac0e64bfe9250e1f294705d1a424c78 /lib
parentffbc03bc75b39c7bd412e7cc6d2185c11b0ffedd (diff)
parent931749bf78b969c54de9bbc67cf29b13a40bb73b (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig14
-rw-r--r--lib/Makefile3
-rw-r--r--lib/cordic.c101
-rw-r--r--lib/crc8.c86
4 files changed, 204 insertions, 0 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 830181cc7a83..32f3e5ae2be5 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -79,6 +79,13 @@ config LIBCRC32C
79 require M here. See Castagnoli93. 79 require M here. See Castagnoli93.
80 Module will be libcrc32c. 80 Module will be libcrc32c.
81 81
82config CRC8
83 tristate "CRC8 function"
84 help
85 This option provides CRC8 function. Drivers may select this
86 when they need to do cyclic redundancy check according CRC8
87 algorithm. Module will be called crc8.
88
82config AUDIT_GENERIC 89config AUDIT_GENERIC
83 bool 90 bool
84 depends on AUDIT && !AUDIT_ARCH 91 depends on AUDIT && !AUDIT_ARCH
@@ -262,4 +269,11 @@ config AVERAGE
262 269
263 If unsure, say N. 270 If unsure, say N.
264 271
272config CORDIC
273 tristate "Cordic function"
274 help
275 The option provides arithmetic function using cordic algorithm
276 so its calculations are in fixed point. Modules can select this
277 when they require this function. Module will be called cordic.
278
265endmenu 279endmenu
diff --git a/lib/Makefile b/lib/Makefile
index 6b597fdb1898..892f4e282ea1 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_CRC_ITU_T) += crc-itu-t.o
61obj-$(CONFIG_CRC32) += crc32.o 61obj-$(CONFIG_CRC32) += crc32.o
62obj-$(CONFIG_CRC7) += crc7.o 62obj-$(CONFIG_CRC7) += crc7.o
63obj-$(CONFIG_LIBCRC32C) += libcrc32c.o 63obj-$(CONFIG_LIBCRC32C) += libcrc32c.o
64obj-$(CONFIG_CRC8) += crc8.o
64obj-$(CONFIG_GENERIC_ALLOCATOR) += genalloc.o 65obj-$(CONFIG_GENERIC_ALLOCATOR) += genalloc.o
65 66
66obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate/ 67obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate/
@@ -112,6 +113,8 @@ obj-$(CONFIG_AVERAGE) += average.o
112 113
113obj-$(CONFIG_CPU_RMAP) += cpu_rmap.o 114obj-$(CONFIG_CPU_RMAP) += cpu_rmap.o
114 115
116obj-$(CONFIG_CORDIC) += cordic.o
117
115hostprogs-y := gen_crc32table 118hostprogs-y := gen_crc32table
116clean-files := crc32table.h 119clean-files := crc32table.h
117 120
diff --git a/lib/cordic.c b/lib/cordic.c
new file mode 100644
index 000000000000..aa27a88d7e04
--- /dev/null
+++ b/lib/cordic.c
@@ -0,0 +1,101 @@
1/*
2 * Copyright (c) 2011 Broadcom Corporation
3 *
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
11 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
13 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
14 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16#include <linux/module.h>
17#include <linux/cordic.h>
18
19#define CORDIC_ANGLE_GEN 39797
20#define CORDIC_PRECISION_SHIFT 16
21#define CORDIC_NUM_ITER (CORDIC_PRECISION_SHIFT + 2)
22
23#define FIXED(X) ((s32)((X) << CORDIC_PRECISION_SHIFT))
24#define FLOAT(X) (((X) >= 0) \
25 ? ((((X) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1) \
26 : -((((-(X)) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1))
27
28static const s32 arctan_table[] = {
29 2949120,
30 1740967,
31 919879,
32 466945,
33 234379,
34 117304,
35 58666,
36 29335,
37 14668,
38 7334,
39 3667,
40 1833,
41 917,
42 458,
43 229,
44 115,
45 57,
46 29
47};
48
49/*
50 * cordic_calc_iq() - calculates the i/q coordinate for given angle
51 *
52 * theta: angle in degrees for which i/q coordinate is to be calculated
53 * coord: function output parameter holding the i/q coordinate
54 */
55struct cordic_iq cordic_calc_iq(s32 theta)
56{
57 struct cordic_iq coord;
58 s32 angle, valtmp;
59 unsigned iter;
60 int signx = 1;
61 int signtheta;
62
63 coord.i = CORDIC_ANGLE_GEN;
64 coord.q = 0;
65 angle = 0;
66
67 theta = FIXED(theta);
68 signtheta = (theta < 0) ? -1 : 1;
69 theta = ((theta + FIXED(180) * signtheta) % FIXED(360)) -
70 FIXED(180) * signtheta;
71
72 if (FLOAT(theta) > 90) {
73 theta -= FIXED(180);
74 signx = -1;
75 } else if (FLOAT(theta) < -90) {
76 theta += FIXED(180);
77 signx = -1;
78 }
79
80 for (iter = 0; iter < CORDIC_NUM_ITER; iter++) {
81 if (theta > angle) {
82 valtmp = coord.i - (coord.q >> iter);
83 coord.q += (coord.i >> iter);
84 angle += arctan_table[iter];
85 } else {
86 valtmp = coord.i + (coord.q >> iter);
87 coord.q -= (coord.i >> iter);
88 angle -= arctan_table[iter];
89 }
90 coord.i = valtmp;
91 }
92
93 coord.i *= signx;
94 coord.q *= signx;
95 return coord;
96}
97EXPORT_SYMBOL(cordic_calc_iq);
98
99MODULE_DESCRIPTION("Cordic functions");
100MODULE_AUTHOR("Broadcom Corporation");
101MODULE_LICENSE("Dual BSD/GPL");
diff --git a/lib/crc8.c b/lib/crc8.c
new file mode 100644
index 000000000000..87b59cafdb83
--- /dev/null
+++ b/lib/crc8.c
@@ -0,0 +1,86 @@
1/*
2 * Copyright (c) 2011 Broadcom Corporation
3 *
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
11 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
13 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
14 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19#include <linux/module.h>
20#include <linux/crc8.h>
21#include <linux/printk.h>
22
23/*
24 * crc8_populate_msb - fill crc table for given polynomial in reverse bit order.
25 *
26 * table: table to be filled.
27 * polynomial: polynomial for which table is to be filled.
28 */
29void crc8_populate_msb(u8 table[CRC8_TABLE_SIZE], u8 polynomial)
30{
31 int i, j;
32 const u8 msbit = 0x80;
33 u8 t = msbit;
34
35 table[0] = 0;
36
37 for (i = 1; i < CRC8_TABLE_SIZE; i *= 2) {
38 t = (t << 1) ^ (t & msbit ? polynomial : 0);
39 for (j = 0; j < i; j++)
40 table[i+j] = table[j] ^ t;
41 }
42}
43EXPORT_SYMBOL(crc8_populate_msb);
44
45/*
46 * crc8_populate_lsb - fill crc table for given polynomial in regular bit order.
47 *
48 * table: table to be filled.
49 * polynomial: polynomial for which table is to be filled.
50 */
51void crc8_populate_lsb(u8 table[CRC8_TABLE_SIZE], u8 polynomial)
52{
53 int i, j;
54 u8 t = 1;
55
56 table[0] = 0;
57
58 for (i = (CRC8_TABLE_SIZE >> 1); i; i >>= 1) {
59 t = (t >> 1) ^ (t & 1 ? polynomial : 0);
60 for (j = 0; j < CRC8_TABLE_SIZE; j += 2*i)
61 table[i+j] = table[j] ^ t;
62 }
63}
64EXPORT_SYMBOL(crc8_populate_lsb);
65
66/*
67 * crc8 - calculate a crc8 over the given input data.
68 *
69 * table: crc table used for calculation.
70 * pdata: pointer to data buffer.
71 * nbytes: number of bytes in data buffer.
72 * crc: previous returned crc8 value.
73 */
74u8 crc8(const u8 table[CRC8_TABLE_SIZE], u8 *pdata, size_t nbytes, u8 crc)
75{
76 /* loop over the buffer data */
77 while (nbytes-- > 0)
78 crc = table[(crc ^ *pdata++) & 0xff];
79
80 return crc;
81}
82EXPORT_SYMBOL(crc8);
83
84MODULE_DESCRIPTION("CRC8 (by Williams, Ross N.) function");
85MODULE_AUTHOR("Broadcom Corporation");
86MODULE_LICENSE("Dual BSD/GPL");