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author | Takashi Iwai <tiwai@suse.de> | 2011-08-08 14:30:29 +0200 |
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committer | Takashi Iwai <tiwai@suse.de> | 2011-08-08 14:30:29 +0200 |
commit | 0a2d31b62dba9b5b92a38c67c9cc42630513662a (patch) | |
tree | f755d74ec85248de645e10c45ed1a2ed467530f6 /include/linux/cordic.h | |
parent | 8039290a91c5dc4414093c086987a5d7738fe2fd (diff) | |
parent | df944f66784e6d4f2f50739263a4947885d8b6ae (diff) |
Merge branch 'fix/kconfig' into for-linus
Diffstat (limited to 'include/linux/cordic.h')
-rw-r--r-- | include/linux/cordic.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/include/linux/cordic.h b/include/linux/cordic.h new file mode 100644 index 00000000000..f932093e20c --- /dev/null +++ b/include/linux/cordic.h @@ -0,0 +1,48 @@ +/* + * 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. + */ +#ifndef __CORDIC_H_ +#define __CORDIC_H_ + +#include <linux/types.h> + +/** + * struct cordic_iq - i/q coordinate. + * + * @i: real part of coordinate (in phase). + * @q: imaginary part of coordinate (quadrature). + */ +struct cordic_iq { + s32 i; + s32 q; +}; + +/** + * 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. + * + * The function calculates the i/q coordinate for a given angle using + * cordic algorithm. The coordinate consists of a real (i) and an + * imaginary (q) part. The real part is essentially the cosine of the + * angle and the imaginary part is the sine of the angle. The returned + * values are scaled by 2^16 for precision. The range for theta is + * for -180 degrees to +180 degrees. Passed values outside this range are + * converted before doing the actual calculation. + */ +struct cordic_iq cordic_calc_iq(s32 theta); + +#endif /* __CORDIC_H_ */ |