1/*
2 * linux/drivers/video/omap2/dss/dispc_coefs.c
3 *
4 * Copyright (C) 2011 Texas Instruments
5 * Author: Chandrabhanu Mahapatra <cmahapatra@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License along with
17 * this program.  If not, see <http://www.gnu.org/licenses/>.
18 */
19
20#include <linux/kernel.h>
21#include <video/omapdss.h>
22
23#include "dispc.h"
24
25static const struct dispc_coef coef3_M8[8] = {
26	{ 0,  0, 128,  0, 0 },
27	{ 0, -4, 123,  9, 0 },
28	{ 0, -4, 108, 24, 0 },
29	{ 0, -2,  87, 43, 0 },
30	{ 0, 64,  64,  0, 0 },
31	{ 0, 43,  87, -2, 0 },
32	{ 0, 24, 108, -4, 0 },
33	{ 0,  9, 123, -4, 0 },
34};
35
36static const struct dispc_coef coef3_M9[8] = {
37	{ 0,  6, 116,  6, 0 },
38	{ 0,  0, 112, 16, 0 },
39	{ 0, -2, 100, 30, 0 },
40	{ 0, -2,  83, 47, 0 },
41	{ 0, 64,  64,  0, 0 },
42	{ 0, 47,  83, -2, 0 },
43	{ 0, 30, 100, -2, 0 },
44	{ 0, 16, 112,  0, 0 },
45};
46
47static const struct dispc_coef coef3_M10[8] = {
48	{ 0, 10, 108, 10, 0 },
49	{ 0,  3, 104, 21, 0 },
50	{ 0,  0,  94, 34, 0 },
51	{ 0, -1,  80, 49, 0 },
52	{ 0, 64,  64,  0, 0 },
53	{ 0, 49,  80, -1, 0 },
54	{ 0, 34,  94,  0, 0 },
55	{ 0, 21, 104,  3, 0 },
56};
57
58static const struct dispc_coef coef3_M11[8] = {
59	{ 0, 14, 100, 14, 0 },
60	{ 0,  6,  98, 24, 0 },
61	{ 0,  2,  90, 36, 0 },
62	{ 0,  0,  78, 50, 0 },
63	{ 0, 64,  64,  0, 0 },
64	{ 0, 50,  78,  0, 0 },
65	{ 0, 36,  90,  2, 0 },
66	{ 0, 24,  98,  6, 0 },
67};
68
69static const struct dispc_coef coef3_M12[8] = {
70	{ 0, 16,  96, 16, 0 },
71	{ 0,  9,  93, 26, 0 },
72	{ 0,  4,  86, 38, 0 },
73	{ 0,  1,  76, 51, 0 },
74	{ 0, 64,  64,  0, 0 },
75	{ 0, 51,  76,  1, 0 },
76	{ 0, 38,  86,  4, 0 },
77	{ 0, 26,  93,  9, 0 },
78};
79
80static const struct dispc_coef coef3_M13[8] = {
81	{ 0, 18,  92, 18, 0 },
82	{ 0, 10,  90, 28, 0 },
83	{ 0,  5,  83, 40, 0 },
84	{ 0,  1,  75, 52, 0 },
85	{ 0, 64,  64,  0, 0 },
86	{ 0, 52,  75,  1, 0 },
87	{ 0, 40,  83,  5, 0 },
88	{ 0, 28,  90, 10, 0 },
89};
90
91static const struct dispc_coef coef3_M14[8] = {
92	{ 0, 20, 88, 20, 0 },
93	{ 0, 12, 86, 30, 0 },
94	{ 0,  6, 81, 41, 0 },
95	{ 0,  2, 74, 52, 0 },
96	{ 0, 64, 64,  0, 0 },
97	{ 0, 52, 74,  2, 0 },
98	{ 0, 41, 81,  6, 0 },
99	{ 0, 30, 86, 12, 0 },
100};
101
102static const struct dispc_coef coef3_M16[8] = {
103	{ 0, 22, 84, 22, 0 },
104	{ 0, 14, 82, 32, 0 },
105	{ 0,  8, 78, 42, 0 },
106	{ 0,  3, 72, 53, 0 },
107	{ 0, 64, 64,  0, 0 },
108	{ 0, 53, 72,  3, 0 },
109	{ 0, 42, 78,  8, 0 },
110	{ 0, 32, 82, 14, 0 },
111};
112
113static const struct dispc_coef coef3_M19[8] = {
114	{ 0, 24, 80, 24, 0 },
115	{ 0, 16, 79, 33, 0 },
116	{ 0,  9, 76, 43, 0 },
117	{ 0,  4, 70, 54, 0 },
118	{ 0, 64, 64,  0, 0 },
119	{ 0, 54, 70,  4, 0 },
120	{ 0, 43, 76,  9, 0 },
121	{ 0, 33, 79, 16, 0 },
122};
123
124static const struct dispc_coef coef3_M22[8] = {
125	{ 0, 25, 78, 25, 0 },
126	{ 0, 17, 77, 34, 0 },
127	{ 0, 10, 74, 44, 0 },
128	{ 0,  5, 69, 54, 0 },
129	{ 0, 64, 64,  0, 0 },
130	{ 0, 54, 69,  5, 0 },
131	{ 0, 44, 74, 10, 0 },
132	{ 0, 34, 77, 17, 0 },
133};
134
135static const struct dispc_coef coef3_M26[8] = {
136	{ 0, 26, 76, 26, 0 },
137	{ 0, 19, 74, 35, 0 },
138	{ 0, 11, 72, 45, 0 },
139	{ 0,  5, 69, 54, 0 },
140	{ 0, 64, 64,  0, 0 },
141	{ 0, 54, 69,  5, 0 },
142	{ 0, 45, 72, 11, 0 },
143	{ 0, 35, 74, 19, 0 },
144};
145
146static const struct dispc_coef coef3_M32[8] = {
147	{ 0, 27, 74, 27, 0 },
148	{ 0, 19, 73, 36, 0 },
149	{ 0, 12, 71, 45, 0 },
150	{ 0,  6, 68, 54, 0 },
151	{ 0, 64, 64,  0, 0 },
152	{ 0, 54, 68,  6, 0 },
153	{ 0, 45, 71, 12, 0 },
154	{ 0, 36, 73, 19, 0 },
155};
156
157static const struct dispc_coef coef5_M8[8] = {
158	{   0,   0, 128,   0,   0 },
159	{  -2,  14, 125, -10,   1 },
160	{  -6,  33, 114, -15,   2 },
161	{ -10,  55,  98, -16,   1 },
162	{   0, -14,  78,  78, -14 },
163	{   1, -16,  98,  55, -10 },
164	{   2, -15, 114,  33,  -6 },
165	{   1, -10, 125,  14,  -2 },
166};
167
168static const struct dispc_coef coef5_M9[8] = {
169	{  -3,  10, 114,  10,  -3 },
170	{  -6,  24, 111,   0,  -1 },
171	{  -8,  40, 103,  -7,   0 },
172	{ -11,  58,  91, -11,   1 },
173	{   0, -12,  76,  76, -12 },
174	{   1, -11,  91,  58, -11 },
175	{   0,  -7, 103,  40,  -8 },
176	{  -1,   0, 111,  24,  -6 },
177};
178
179static const struct dispc_coef coef5_M10[8] = {
180	{  -4,  18, 100,  18,  -4 },
181	{  -6,  30,  99,   8,  -3 },
182	{  -8,  44,  93,   0,  -1 },
183	{  -9,  58,  84,  -5,   0 },
184	{   0,  -8,  72,  72,  -8 },
185	{   0,  -5,  84,  58,  -9 },
186	{  -1,   0,  93,  44,  -8 },
187	{  -3,   8,  99,  30,  -6 },
188};
189
190static const struct dispc_coef coef5_M11[8] = {
191	{  -5,  23,  92,  23,  -5 },
192	{  -6,  34,  90,  13,  -3 },
193	{  -6,  45,  85,   6,  -2 },
194	{  -6,  57,  78,   0,  -1 },
195	{   0,  -4,  68,  68,  -4 },
196	{  -1,   0,  78,  57,  -6 },
197	{  -2,   6,  85,  45,  -6 },
198	{  -3,  13,  90,  34,  -6 },
199};
200
201static const struct dispc_coef coef5_M12[8] = {
202	{  -4,  26,  84,  26,  -4 },
203	{  -5,  36,  82,  18,  -3 },
204	{  -4,  46,  78,  10,  -2 },
205	{  -3,  55,  72,   5,  -1 },
206	{   0,   0,  64,  64,   0 },
207	{  -1,   5,  72,  55,  -3 },
208	{  -2,  10,  78,  46,  -4 },
209	{  -3,  18,  82,  36,  -5 },
210};
211
212static const struct dispc_coef coef5_M13[8] = {
213	{  -3,  28,  78,  28,  -3 },
214	{  -3,  37,  76,  21,  -3 },
215	{  -2,  45,  73,  14,  -2 },
216	{   0,  53,  68,   8,  -1 },
217	{   0,   3,  61,  61,   3 },
218	{  -1,   8,  68,  53,   0 },
219	{  -2,  14,  73,  45,  -2 },
220	{  -3,  21,  76,  37,  -3 },
221};
222
223static const struct dispc_coef coef5_M14[8] = {
224	{  -2,  30,  72,  30,  -2 },
225	{  -1,  37,  71,  23,  -2 },
226	{   0,  45,  69,  16,  -2 },
227	{   3,  52,  64,  10,  -1 },
228	{   0,   6,  58,  58,   6 },
229	{  -1,  10,  64,  52,   3 },
230	{  -2,  16,  69,  45,   0 },
231	{  -2,  23,  71,  37,  -1 },
232};
233
234static const struct dispc_coef coef5_M16[8] = {
235	{   0,  31,  66,  31,   0 },
236	{   1,  38,  65,  25,  -1 },
237	{   3,  44,  62,  20,  -1 },
238	{   6,  49,  59,  14,   0 },
239	{   0,  10,  54,  54,  10 },
240	{   0,  14,  59,  49,   6 },
241	{  -1,  20,  62,  44,   3 },
242	{  -1,  25,  65,  38,   1 },
243};
244
245static const struct dispc_coef coef5_M19[8] = {
246	{   3,  32,  58,  32,   3 },
247	{   4,  38,  58,  27,   1 },
248	{   7,  42,  55,  23,   1 },
249	{  10,  46,  54,  18,   0 },
250	{   0,  14,  50,  50,  14 },
251	{   0,  18,  54,  46,  10 },
252	{   1,  23,  55,  42,   7 },
253	{   1,  27,  58,  38,   4 },
254};
255
256static const struct dispc_coef coef5_M22[8] = {
257	{   4,  33,  54,  33,   4 },
258	{   6,  37,  54,  28,   3 },
259	{   9,  41,  53,  24,   1 },
260	{  12,  45,  51,  20,   0 },
261	{   0,  16,  48,  48,  16 },
262	{   0,  20,  51,  45,  12 },
263	{   1,  24,  53,  41,   9 },
264	{   3,  28,  54,  37,   6 },
265};
266
267static const struct dispc_coef coef5_M26[8] = {
268	{   6,  33,  50,  33,   6 },
269	{   8,  36,  51,  29,   4 },
270	{  11,  40,  50,  25,   2 },
271	{  14,  43,  48,  22,   1 },
272	{   0,  18,  46,  46,  18 },
273	{   1,  22,  48,  43,  14 },
274	{   2,  25,  50,  40,  11 },
275	{   4,  29,  51,  36,   8 },
276};
277
278static const struct dispc_coef coef5_M32[8] = {
279	{   7,  33,  48,  33,   7 },
280	{  10,  36,  48,  29,   5 },
281	{  13,  39,  47,  26,   3 },
282	{  16,  42,  46,  23,   1 },
283	{   0,  19,  45,  45,  19 },
284	{   1,  23,  46,  42,  16 },
285	{   3,  26,  47,  39,  13 },
286	{   5,  29,  48,  36,  10 },
287};
288
289const struct dispc_coef *dispc_ovl_get_scale_coef(int inc, int five_taps)
290{
291	int i;
292	static const struct {
293		int Mmin;
294		int Mmax;
295		const struct dispc_coef *coef_3;
296		const struct dispc_coef *coef_5;
297	} coefs[] = {
298		{ 27, 32, coef3_M32, coef5_M32 },
299		{ 23, 26, coef3_M26, coef5_M26 },
300		{ 20, 22, coef3_M22, coef5_M22 },
301		{ 17, 19, coef3_M19, coef5_M19 },
302		{ 15, 16, coef3_M16, coef5_M16 },
303		{ 14, 14, coef3_M14, coef5_M14 },
304		{ 13, 13, coef3_M13, coef5_M13 },
305		{ 12, 12, coef3_M12, coef5_M12 },
306		{ 11, 11, coef3_M11, coef5_M11 },
307		{ 10, 10, coef3_M10, coef5_M10 },
308		{  9,  9,  coef3_M9,  coef5_M9 },
309		{  4,  8,  coef3_M8,  coef5_M8 },
310		/*
311		 * When upscaling more than two times, blockiness and outlines
312		 * around the image are observed when M8 tables are used. M11,
313		 * M16 and M19 tables are used to prevent this.
314		 */
315		{  3,  3, coef3_M11, coef5_M11 },
316		{  2,  2, coef3_M16, coef5_M16 },
317		{  0,  1, coef3_M19, coef5_M19 },
318	};
319
320	inc /= 128;
321	for (i = 0; i < ARRAY_SIZE(coefs); ++i)
322		if (inc >= coefs[i].Mmin && inc <= coefs[i].Mmax)
323			return five_taps ? coefs[i].coef_5 : coefs[i].coef_3;
324	return NULL;
325}
326