1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Support for Intel Camera Imaging ISP subsystem.
4 * Copyright (c) 2015, Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 */
15
16 #ifndef __SH_CSS_FRAC_H
17 #define __SH_CSS_FRAC_H
18
19 #include <linux/minmax.h>
20
21 #include "mamoiada_params.h"
22
23 #define sISP_REG_BIT ISP_VEC_ELEMBITS
24 #define uISP_REG_BIT ((unsigned int)(sISP_REG_BIT - 1))
25 #define sSHIFT (16 - sISP_REG_BIT)
26 #define uSHIFT ((unsigned int)(16 - uISP_REG_BIT))
27 #define sFRACTION_BITS_FITTING(a) (a - sSHIFT)
28 #define uFRACTION_BITS_FITTING(a) ((unsigned int)(a - uSHIFT))
29 #define sISP_VAL_MIN (-(1 << uISP_REG_BIT))
30 #define sISP_VAL_MAX ((1 << uISP_REG_BIT) - 1)
31 #define uISP_VAL_MIN (0U)
32 #define uISP_VAL_MAX ((unsigned int)((1 << uISP_REG_BIT) - 1))
33
34 /* a:fraction bits for 16bit precision, b:fraction bits for ISP precision */
sDIGIT_FITTING(int v,int a,int b)35 static inline int sDIGIT_FITTING(int v, int a, int b)
36 {
37 int fit_shift = sFRACTION_BITS_FITTING(a) - b;
38
39 v >>= sSHIFT;
40 v >>= fit_shift > 0 ? fit_shift : 0;
41
42 return clamp_t(int, v, sISP_VAL_MIN, sISP_VAL_MAX);
43 }
44
uDIGIT_FITTING(unsigned int v,int a,int b)45 static inline unsigned int uDIGIT_FITTING(unsigned int v, int a, int b)
46 {
47 int fit_shift = uFRACTION_BITS_FITTING(a) - b;
48
49 v >>= uSHIFT;
50 v >>= fit_shift > 0 ? fit_shift : 0;
51
52 return clamp_t(unsigned int, v, uISP_VAL_MIN, uISP_VAL_MAX);
53 }
54
55 #endif /* __SH_CSS_FRAC_H */
56