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-rw-r--r--drivers/media/IR/ir-nec-decoder.c216
1 files changed, 0 insertions, 216 deletions
diff --git a/drivers/media/IR/ir-nec-decoder.c b/drivers/media/IR/ir-nec-decoder.c
deleted file mode 100644
index d597421d6547..000000000000
--- a/drivers/media/IR/ir-nec-decoder.c
+++ /dev/null
@@ -1,216 +0,0 @@
1/* ir-nec-decoder.c - handle NEC IR Pulse/Space protocol
2 *
3 * Copyright (C) 2010 by Mauro Carvalho Chehab <mchehab@redhat.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15#include <linux/bitrev.h>
16#include "ir-core-priv.h"
17
18#define NEC_NBITS 32
19#define NEC_UNIT 562500 /* ns */
20#define NEC_HEADER_PULSE (16 * NEC_UNIT)
21#define NECX_HEADER_PULSE (8 * NEC_UNIT) /* Less common NEC variant */
22#define NEC_HEADER_SPACE (8 * NEC_UNIT)
23#define NEC_REPEAT_SPACE (4 * NEC_UNIT)
24#define NEC_BIT_PULSE (1 * NEC_UNIT)
25#define NEC_BIT_0_SPACE (1 * NEC_UNIT)
26#define NEC_BIT_1_SPACE (3 * NEC_UNIT)
27#define NEC_TRAILER_PULSE (1 * NEC_UNIT)
28#define NEC_TRAILER_SPACE (10 * NEC_UNIT) /* even longer in reality */
29#define NECX_REPEAT_BITS 1
30
31enum nec_state {
32 STATE_INACTIVE,
33 STATE_HEADER_SPACE,
34 STATE_BIT_PULSE,
35 STATE_BIT_SPACE,
36 STATE_TRAILER_PULSE,
37 STATE_TRAILER_SPACE,
38};
39
40/**
41 * ir_nec_decode() - Decode one NEC pulse or space
42 * @input_dev: the struct input_dev descriptor of the device
43 * @duration: the struct ir_raw_event descriptor of the pulse/space
44 *
45 * This function returns -EINVAL if the pulse violates the state machine
46 */
47static int ir_nec_decode(struct input_dev *input_dev, struct ir_raw_event ev)
48{
49 struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
50 struct nec_dec *data = &ir_dev->raw->nec;
51 u32 scancode;
52 u8 address, not_address, command, not_command;
53
54 if (!(ir_dev->raw->enabled_protocols & IR_TYPE_NEC))
55 return 0;
56
57 if (IS_RESET(ev)) {
58 data->state = STATE_INACTIVE;
59 return 0;
60 }
61
62 IR_dprintk(2, "NEC decode started at state %d (%uus %s)\n",
63 data->state, TO_US(ev.duration), TO_STR(ev.pulse));
64
65 switch (data->state) {
66
67 case STATE_INACTIVE:
68 if (!ev.pulse)
69 break;
70
71 if (eq_margin(ev.duration, NEC_HEADER_PULSE, NEC_UNIT / 2)) {
72 data->is_nec_x = false;
73 data->necx_repeat = false;
74 } else if (eq_margin(ev.duration, NECX_HEADER_PULSE, NEC_UNIT / 2))
75 data->is_nec_x = true;
76 else
77 break;
78
79 data->count = 0;
80 data->state = STATE_HEADER_SPACE;
81 return 0;
82
83 case STATE_HEADER_SPACE:
84 if (ev.pulse)
85 break;
86
87 if (eq_margin(ev.duration, NEC_HEADER_SPACE, NEC_UNIT / 2)) {
88 data->state = STATE_BIT_PULSE;
89 return 0;
90 } else if (eq_margin(ev.duration, NEC_REPEAT_SPACE, NEC_UNIT / 2)) {
91 ir_repeat(input_dev);
92 IR_dprintk(1, "Repeat last key\n");
93 data->state = STATE_TRAILER_PULSE;
94 return 0;
95 }
96
97 break;
98
99 case STATE_BIT_PULSE:
100 if (!ev.pulse)
101 break;
102
103 if (!eq_margin(ev.duration, NEC_BIT_PULSE, NEC_UNIT / 2))
104 break;
105
106 data->state = STATE_BIT_SPACE;
107 return 0;
108
109 case STATE_BIT_SPACE:
110 if (ev.pulse)
111 break;
112
113 if (data->necx_repeat && data->count == NECX_REPEAT_BITS &&
114 geq_margin(ev.duration,
115 NEC_TRAILER_SPACE, NEC_UNIT / 2)) {
116 IR_dprintk(1, "Repeat last key\n");
117 ir_repeat(input_dev);
118 data->state = STATE_INACTIVE;
119 return 0;
120
121 } else if (data->count > NECX_REPEAT_BITS)
122 data->necx_repeat = false;
123
124 data->bits <<= 1;
125 if (eq_margin(ev.duration, NEC_BIT_1_SPACE, NEC_UNIT / 2))
126 data->bits |= 1;
127 else if (!eq_margin(ev.duration, NEC_BIT_0_SPACE, NEC_UNIT / 2))
128 break;
129 data->count++;
130
131 if (data->count == NEC_NBITS)
132 data->state = STATE_TRAILER_PULSE;
133 else
134 data->state = STATE_BIT_PULSE;
135
136 return 0;
137
138 case STATE_TRAILER_PULSE:
139 if (!ev.pulse)
140 break;
141
142 if (!eq_margin(ev.duration, NEC_TRAILER_PULSE, NEC_UNIT / 2))
143 break;
144
145 data->state = STATE_TRAILER_SPACE;
146 return 0;
147
148 case STATE_TRAILER_SPACE:
149 if (ev.pulse)
150 break;
151
152 if (!geq_margin(ev.duration, NEC_TRAILER_SPACE, NEC_UNIT / 2))
153 break;
154
155 address = bitrev8((data->bits >> 24) & 0xff);
156 not_address = bitrev8((data->bits >> 16) & 0xff);
157 command = bitrev8((data->bits >> 8) & 0xff);
158 not_command = bitrev8((data->bits >> 0) & 0xff);
159
160 if ((command ^ not_command) != 0xff) {
161 IR_dprintk(1, "NEC checksum error: received 0x%08x\n",
162 data->bits);
163 break;
164 }
165
166 if ((address ^ not_address) != 0xff) {
167 /* Extended NEC */
168 scancode = address << 16 |
169 not_address << 8 |
170 command;
171 IR_dprintk(1, "NEC (Ext) scancode 0x%06x\n", scancode);
172 } else {
173 /* Normal NEC */
174 scancode = address << 8 | command;
175 IR_dprintk(1, "NEC scancode 0x%04x\n", scancode);
176 }
177
178 if (data->is_nec_x)
179 data->necx_repeat = true;
180
181 ir_keydown(input_dev, scancode, 0);
182 data->state = STATE_INACTIVE;
183 return 0;
184 }
185
186 IR_dprintk(1, "NEC decode failed at state %d (%uus %s)\n",
187 data->state, TO_US(ev.duration), TO_STR(ev.pulse));
188 data->state = STATE_INACTIVE;
189 return -EINVAL;
190}
191
192static struct ir_raw_handler nec_handler = {
193 .protocols = IR_TYPE_NEC,
194 .decode = ir_nec_decode,
195};
196
197static int __init ir_nec_decode_init(void)
198{
199 ir_raw_handler_register(&nec_handler);
200
201 printk(KERN_INFO "IR NEC protocol handler initialized\n");
202 return 0;
203}
204
205static void __exit ir_nec_decode_exit(void)
206{
207 ir_raw_handler_unregister(&nec_handler);
208}
209
210module_init(ir_nec_decode_init);
211module_exit(ir_nec_decode_exit);
212
213MODULE_LICENSE("GPL");
214MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
215MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
216MODULE_DESCRIPTION("NEC IR protocol decoder");
generated by cgit v1.2.2 (git 2.25.0) at 2025-03-20 21:56:19 -0400