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path: root/drivers/media/rc/ir-sony-decoder.c
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Diffstat (limited to 'drivers/media/rc/ir-sony-decoder.c')
-rw-r--r--drivers/media/rc/ir-sony-decoder.c181
1 files changed, 181 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-sony-decoder.c b/drivers/media/rc/ir-sony-decoder.c
new file mode 100644
index 000000000000..a92de80c48db
--- /dev/null
+++ b/drivers/media/rc/ir-sony-decoder.c
@@ -0,0 +1,181 @@
1/* ir-sony-decoder.c - handle Sony IR Pulse/Space protocol
2 *
3 * Copyright (C) 2010 by David Härdeman <david@hardeman.nu>
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 "rc-core-priv.h"
17
18#define SONY_UNIT 600000 /* ns */
19#define SONY_HEADER_PULSE (4 * SONY_UNIT)
20#define SONY_HEADER_SPACE (1 * SONY_UNIT)
21#define SONY_BIT_0_PULSE (1 * SONY_UNIT)
22#define SONY_BIT_1_PULSE (2 * SONY_UNIT)
23#define SONY_BIT_SPACE (1 * SONY_UNIT)
24#define SONY_TRAILER_SPACE (10 * SONY_UNIT) /* minimum */
25
26enum sony_state {
27 STATE_INACTIVE,
28 STATE_HEADER_SPACE,
29 STATE_BIT_PULSE,
30 STATE_BIT_SPACE,
31 STATE_FINISHED,
32};
33
34/**
35 * ir_sony_decode() - Decode one Sony pulse or space
36 * @dev: the struct rc_dev descriptor of the device
37 * @ev: the struct ir_raw_event descriptor of the pulse/space
38 *
39 * This function returns -EINVAL if the pulse violates the state machine
40 */
41static int ir_sony_decode(struct rc_dev *dev, struct ir_raw_event ev)
42{
43 struct sony_dec *data = &dev->raw->sony;
44 u32 scancode;
45 u8 device, subdevice, function;
46
47 if (!(dev->raw->enabled_protocols & RC_TYPE_SONY))
48 return 0;
49
50 if (!is_timing_event(ev)) {
51 if (ev.reset)
52 data->state = STATE_INACTIVE;
53 return 0;
54 }
55
56 if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2))
57 goto out;
58
59 IR_dprintk(2, "Sony decode started at state %d (%uus %s)\n",
60 data->state, TO_US(ev.duration), TO_STR(ev.pulse));
61
62 switch (data->state) {
63
64 case STATE_INACTIVE:
65 if (!ev.pulse)
66 break;
67
68 if (!eq_margin(ev.duration, SONY_HEADER_PULSE, SONY_UNIT / 2))
69 break;
70
71 data->count = 0;
72 data->state = STATE_HEADER_SPACE;
73 return 0;
74
75 case STATE_HEADER_SPACE:
76 if (ev.pulse)
77 break;
78
79 if (!eq_margin(ev.duration, SONY_HEADER_SPACE, SONY_UNIT / 2))
80 break;
81
82 data->state = STATE_BIT_PULSE;
83 return 0;
84
85 case STATE_BIT_PULSE:
86 if (!ev.pulse)
87 break;
88
89 data->bits <<= 1;
90 if (eq_margin(ev.duration, SONY_BIT_1_PULSE, SONY_UNIT / 2))
91 data->bits |= 1;
92 else if (!eq_margin(ev.duration, SONY_BIT_0_PULSE, SONY_UNIT / 2))
93 break;
94
95 data->count++;
96 data->state = STATE_BIT_SPACE;
97 return 0;
98
99 case STATE_BIT_SPACE:
100 if (ev.pulse)
101 break;
102
103 if (!geq_margin(ev.duration, SONY_BIT_SPACE, SONY_UNIT / 2))
104 break;
105
106 decrease_duration(&ev, SONY_BIT_SPACE);
107
108 if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2)) {
109 data->state = STATE_BIT_PULSE;
110 return 0;
111 }
112
113 data->state = STATE_FINISHED;
114 /* Fall through */
115
116 case STATE_FINISHED:
117 if (ev.pulse)
118 break;
119
120 if (!geq_margin(ev.duration, SONY_TRAILER_SPACE, SONY_UNIT / 2))
121 break;
122
123 switch (data->count) {
124 case 12:
125 device = bitrev8((data->bits << 3) & 0xF8);
126 subdevice = 0;
127 function = bitrev8((data->bits >> 4) & 0xFE);
128 break;
129 case 15:
130 device = bitrev8((data->bits >> 0) & 0xFF);
131 subdevice = 0;
132 function = bitrev8((data->bits >> 7) & 0xFD);
133 break;
134 case 20:
135 device = bitrev8((data->bits >> 5) & 0xF8);
136 subdevice = bitrev8((data->bits >> 0) & 0xFF);
137 function = bitrev8((data->bits >> 12) & 0xFE);
138 break;
139 default:
140 IR_dprintk(1, "Sony invalid bitcount %u\n", data->count);
141 goto out;
142 }
143
144 scancode = device << 16 | subdevice << 8 | function;
145 IR_dprintk(1, "Sony(%u) scancode 0x%05x\n", data->count, scancode);
146 rc_keydown(dev, scancode, 0);
147 data->state = STATE_INACTIVE;
148 return 0;
149 }
150
151out:
152 IR_dprintk(1, "Sony decode failed at state %d (%uus %s)\n",
153 data->state, TO_US(ev.duration), TO_STR(ev.pulse));
154 data->state = STATE_INACTIVE;
155 return -EINVAL;
156}
157
158static struct ir_raw_handler sony_handler = {
159 .protocols = RC_TYPE_SONY,
160 .decode = ir_sony_decode,
161};
162
163static int __init ir_sony_decode_init(void)
164{
165 ir_raw_handler_register(&sony_handler);
166
167 printk(KERN_INFO "IR Sony protocol handler initialized\n");
168 return 0;
169}
170
171static void __exit ir_sony_decode_exit(void)
172{
173 ir_raw_handler_unregister(&sony_handler);
174}
175
176module_init(ir_sony_decode_init);
177module_exit(ir_sony_decode_exit);
178
179MODULE_LICENSE("GPL");
180MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
181MODULE_DESCRIPTION("Sony IR protocol decoder");
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-25 07:41:14 -0500