1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ImgTec IR Decoder setup for Philips RC-5 protocol.
4 *
5 * Copyright 2012-2014 Imagination Technologies Ltd.
6 */
7
8#include "img-ir-hw.h"
9
10/* Convert RC5 data to a scancode */
11static int img_ir_rc5_scancode(int len, u64 raw, u64 enabled_protocols,
12				struct img_ir_scancode_req *request)
13{
14	unsigned int addr, cmd, tgl, start;
15
16	/* Quirk in the decoder shifts everything by 2 to the left. */
17	raw   >>= 2;
18
19	start	=  (raw >> 13)	& 0x01;
20	tgl	=  (raw >> 11)	& 0x01;
21	addr	=  (raw >>  6)	& 0x1f;
22	cmd	=   raw		& 0x3f;
23	/*
24	 * 12th bit is used to extend the command in extended RC5 and has
25	 * no effect on standard RC5.
26	 */
27	cmd	+= ((raw >> 12) & 0x01) ? 0 : 0x40;
28
29	if (!start)
30		return -EINVAL;
31
32	request->protocol = RC_PROTO_RC5;
33	request->scancode = addr << 8 | cmd;
34	request->toggle   = tgl;
35	return IMG_IR_SCANCODE;
36}
37
38/* Convert RC5 scancode to RC5 data filter */
39static int img_ir_rc5_filter(const struct rc_scancode_filter *in,
40				 struct img_ir_filter *out, u64 protocols)
41{
42	/* Not supported by the hw. */
43	return -EINVAL;
44}
45
46/*
47 * RC-5 decoder
48 * see http://www.sbprojects.com/knowledge/ir/rc5.php
49 */
50struct img_ir_decoder img_ir_rc5 = {
51	.type      = RC_PROTO_BIT_RC5,
52	.control   = {
53		.bitoriend2	= 1,
54		.code_type	= IMG_IR_CODETYPE_BIPHASE,
55		.decodend2	= 1,
56	},
57	/* main timings */
58	.tolerance	= 16,
59	.unit		= 888888, /* 1/36k*32=888.888microseconds */
60	.timings	= {
61		/* 10 symbol */
62		.s10 = {
63			.pulse	= { 1 },
64			.space	= { 1 },
65		},
66
67		/* 11 symbol */
68		.s11 = {
69			.pulse	= { 1 },
70			.space	= { 1 },
71		},
72
73		/* free time */
74		.ft  = {
75			.minlen = 14,
76			.maxlen = 14,
77			.ft_min = 5,
78		},
79	},
80
81	/* scancode logic */
82	.scancode	= img_ir_rc5_scancode,
83	.filter		= img_ir_rc5_filter,
84};
85