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58d81d64e0
Now that these macros are in header file, we can eventually clean up the duplicate macros present in the drivers that utilize the same cordic algorithm implementation. Also add CORDIC_ prefix to nonprefixed macros. Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com> Signed-off-by: Priit Laes <plaes@plaes.org> Acked-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
58 lines
2.1 KiB
C
58 lines
2.1 KiB
C
/*
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* Copyright (c) 2011 Broadcom Corporation
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*
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* Permission to use, copy, modify, and/or distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
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* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
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* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
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* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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#ifndef __CORDIC_H_
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#define __CORDIC_H_
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#include <linux/types.h>
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#define CORDIC_ANGLE_GEN 39797
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#define CORDIC_PRECISION_SHIFT 16
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#define CORDIC_NUM_ITER (CORDIC_PRECISION_SHIFT + 2)
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#define CORDIC_FIXED(X) ((s32)((X) << CORDIC_PRECISION_SHIFT))
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#define CORDIC_FLOAT(X) (((X) >= 0) \
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? ((((X) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1) \
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: -((((-(X)) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1))
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/**
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* struct cordic_iq - i/q coordinate.
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*
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* @i: real part of coordinate (in phase).
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* @q: imaginary part of coordinate (quadrature).
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*/
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struct cordic_iq {
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s32 i;
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s32 q;
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};
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/**
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* cordic_calc_iq() - calculates the i/q coordinate for given angle.
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*
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* @theta: angle in degrees for which i/q coordinate is to be calculated.
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* @coord: function output parameter holding the i/q coordinate.
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*
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* The function calculates the i/q coordinate for a given angle using the
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* CORDIC algorithm. The coordinate consists of a real (i) and an
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* imaginary (q) part. The real part is essentially the cosine of the
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* angle and the imaginary part is the sine of the angle. The returned
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* values are scaled by 2^16 for precision. The range for theta is
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* for -180 degrees to +180 degrees. Passed values outside this range are
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* converted before doing the actual calculation.
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*/
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struct cordic_iq cordic_calc_iq(s32 theta);
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#endif /* __CORDIC_H_ */
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