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author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2019-05-14 15:43:05 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-14 19:52:49 -0700 |
commit | 2c64e9cb0b6b858901e9a386860d7d929d1cbaeb (patch) | |
tree | 749da0ef8f5d478680a523c877fb0e16fc18409c /lib/cordic.c | |
parent | b5c56e0cdd62979dd538e5363b06be5bdf735a09 (diff) | |
download | lwn-2c64e9cb0b6b858901e9a386860d7d929d1cbaeb.tar.gz lwn-2c64e9cb0b6b858901e9a386860d7d929d1cbaeb.zip |
lib: Move mathematic helpers to separate folder
For better maintenance and expansion move the mathematic helpers to the
separate folder.
No functional change intended.
Note, the int_sqrt() is not used as a part of lib, so, moved to regular
obj.
Link: http://lkml.kernel.org/r/20190323172531.80025-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Ray Jui <rjui@broadcom.com>
[mchehab+samsung@kernel.org: fix broken doc references for div64.c and gcd.c]
Link: http://lkml.kernel.org/r/734f49bae5d4052b3c25691dfefad59bea2e5843.1555580999.git.mchehab+samsung@kernel.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/cordic.c')
-rw-r--r-- | lib/cordic.c | 92 |
1 files changed, 0 insertions, 92 deletions
diff --git a/lib/cordic.c b/lib/cordic.c deleted file mode 100644 index 8ef27c12956f..000000000000 --- a/lib/cordic.c +++ /dev/null @@ -1,92 +0,0 @@ -/* - * Copyright (c) 2011 Broadcom Corporation - * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES - * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF - * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY - * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES - * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION - * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN - * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. - */ -#include <linux/module.h> -#include <linux/cordic.h> - -static const s32 arctan_table[] = { - 2949120, - 1740967, - 919879, - 466945, - 234379, - 117304, - 58666, - 29335, - 14668, - 7334, - 3667, - 1833, - 917, - 458, - 229, - 115, - 57, - 29 -}; - -/* - * cordic_calc_iq() - calculates the i/q coordinate for given angle - * - * theta: angle in degrees for which i/q coordinate is to be calculated - * coord: function output parameter holding the i/q coordinate - */ -struct cordic_iq cordic_calc_iq(s32 theta) -{ - struct cordic_iq coord; - s32 angle, valtmp; - unsigned iter; - int signx = 1; - int signtheta; - - coord.i = CORDIC_ANGLE_GEN; - coord.q = 0; - angle = 0; - - theta = CORDIC_FIXED(theta); - signtheta = (theta < 0) ? -1 : 1; - theta = ((theta + CORDIC_FIXED(180) * signtheta) % CORDIC_FIXED(360)) - - CORDIC_FIXED(180) * signtheta; - - if (CORDIC_FLOAT(theta) > 90) { - theta -= CORDIC_FIXED(180); - signx = -1; - } else if (CORDIC_FLOAT(theta) < -90) { - theta += CORDIC_FIXED(180); - signx = -1; - } - - for (iter = 0; iter < CORDIC_NUM_ITER; iter++) { - if (theta > angle) { - valtmp = coord.i - (coord.q >> iter); - coord.q += (coord.i >> iter); - angle += arctan_table[iter]; - } else { - valtmp = coord.i + (coord.q >> iter); - coord.q -= (coord.i >> iter); - angle -= arctan_table[iter]; - } - coord.i = valtmp; - } - - coord.i *= signx; - coord.q *= signx; - return coord; -} -EXPORT_SYMBOL(cordic_calc_iq); - -MODULE_DESCRIPTION("CORDIC algorithm"); -MODULE_AUTHOR("Broadcom Corporation"); -MODULE_LICENSE("Dual BSD/GPL"); |