summaryrefslogtreecommitdiffstats
path: root/drivers/media/rc/ir-sony-decoder.c
blob: a47ced763031d2fcf20c15de9c4a837a7a1da101 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
/* ir-sony-decoder.c - handle Sony IR Pulse/Space protocol
 *
 * Copyright (C) 2010 by David Härdeman <david@hardeman.nu>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/bitrev.h>
#include <linux/module.h>
#include "rc-core-priv.h"

#define SONY_UNIT		600000 /* ns */
#define SONY_HEADER_PULSE	(4 * SONY_UNIT)
#define	SONY_HEADER_SPACE	(1 * SONY_UNIT)
#define SONY_BIT_0_PULSE	(1 * SONY_UNIT)
#define SONY_BIT_1_PULSE	(2 * SONY_UNIT)
#define SONY_BIT_SPACE		(1 * SONY_UNIT)
#define SONY_TRAILER_SPACE	(10 * SONY_UNIT) /* minimum */

enum sony_state {
	STATE_INACTIVE,
	STATE_HEADER_SPACE,
	STATE_BIT_PULSE,
	STATE_BIT_SPACE,
	STATE_FINISHED,
};

/**
 * ir_sony_decode() - Decode one Sony pulse or space
 * @dev:	the struct rc_dev descriptor of the device
 * @ev:         the struct ir_raw_event descriptor of the pulse/space
 *
 * This function returns -EINVAL if the pulse violates the state machine
 */
static int ir_sony_decode(struct rc_dev *dev, struct ir_raw_event ev)
{
	struct sony_dec *data = &dev->raw->sony;
	enum rc_proto protocol;
	u32 scancode;
	u8 device, subdevice, function;

	if (!is_timing_event(ev)) {
		if (ev.reset)
			data->state = STATE_INACTIVE;
		return 0;
	}

	if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2))
		goto out;

	IR_dprintk(2, "Sony decode started at state %d (%uus %s)\n",
		   data->state, TO_US(ev.duration), TO_STR(ev.pulse));

	switch (data->state) {

	case STATE_INACTIVE:
		if (!ev.pulse)
			break;

		if (!eq_margin(ev.duration, SONY_HEADER_PULSE, SONY_UNIT / 2))
			break;

		data->count = 0;
		data->state = STATE_HEADER_SPACE;
		return 0;

	case STATE_HEADER_SPACE:
		if (ev.pulse)
			break;

		if (!eq_margin(ev.duration, SONY_HEADER_SPACE, SONY_UNIT / 2))
			break;

		data->state = STATE_BIT_PULSE;
		return 0;

	case STATE_BIT_PULSE:
		if (!ev.pulse)
			break;

		data->bits <<= 1;
		if (eq_margin(ev.duration, SONY_BIT_1_PULSE, SONY_UNIT / 2))
			data->bits |= 1;
		else if (!eq_margin(ev.duration, SONY_BIT_0_PULSE, SONY_UNIT / 2))
			break;

		data->count++;
		data->state = STATE_BIT_SPACE;
		return 0;

	case STATE_BIT_SPACE:
		if (ev.pulse)
			break;

		if (!geq_margin(ev.duration, SONY_BIT_SPACE, SONY_UNIT / 2))
			break;

		decrease_duration(&ev, SONY_BIT_SPACE);

		if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2)) {
			data->state = STATE_BIT_PULSE;
			return 0;
		}

		data->state = STATE_FINISHED;
		/* Fall through */

	case STATE_FINISHED:
		if (ev.pulse)
			break;

		if (!geq_margin(ev.duration, SONY_TRAILER_SPACE, SONY_UNIT / 2))
			break;

		switch (data->count) {
		case 12:
			if (!(dev->enabled_protocols & RC_PROTO_BIT_SONY12))
				goto finish_state_machine;

			device    = bitrev8((data->bits <<  3) & 0xF8);
			subdevice = 0;
			function  = bitrev8((data->bits >>  4) & 0xFE);
			protocol = RC_PROTO_SONY12;
			break;
		case 15:
			if (!(dev->enabled_protocols & RC_PROTO_BIT_SONY15))
				goto finish_state_machine;

			device    = bitrev8((data->bits >>  0) & 0xFF);
			subdevice = 0;
			function  = bitrev8((data->bits >>  7) & 0xFE);
			protocol = RC_PROTO_SONY15;
			break;
		case 20:
			if (!(dev->enabled_protocols & RC_PROTO_BIT_SONY20))
				goto finish_state_machine;

			device    = bitrev8((data->bits >>  5) & 0xF8);
			subdevice = bitrev8((data->bits >>  0) & 0xFF);
			function  = bitrev8((data->bits >> 12) & 0xFE);
			protocol = RC_PROTO_SONY20;
			break;
		default:
			IR_dprintk(1, "Sony invalid bitcount %u\n", data->count);
			goto out;
		}

		scancode = device << 16 | subdevice << 8 | function;
		IR_dprintk(1, "Sony(%u) scancode 0x%05x\n", data->count, scancode);
		rc_keydown(dev, protocol, scancode, 0);
		goto finish_state_machine;
	}

out:
	IR_dprintk(1, "Sony decode failed at state %d (%uus %s)\n",
		   data->state, TO_US(ev.duration), TO_STR(ev.pulse));
	data->state = STATE_INACTIVE;
	return -EINVAL;

finish_state_machine:
	data->state = STATE_INACTIVE;
	return 0;
}

static const struct ir_raw_timings_pl ir_sony_timings = {
	.header_pulse  = SONY_HEADER_PULSE,
	.bit_space     = SONY_BIT_SPACE,
	.bit_pulse[0]  = SONY_BIT_0_PULSE,
	.bit_pulse[1]  = SONY_BIT_1_PULSE,
	.trailer_space = SONY_TRAILER_SPACE + SONY_BIT_SPACE,
	.msb_first     = 0,
};

/**
 * ir_sony_encode() - Encode a scancode as a stream of raw events
 *
 * @protocol:	protocol to encode
 * @scancode:	scancode to encode
 * @events:	array of raw ir events to write into
 * @max:	maximum size of @events
 *
 * Returns:	The number of events written.
 *		-ENOBUFS if there isn't enough space in the array to fit the
 *		encoding. In this case all @max events will have been written.
 */
static int ir_sony_encode(enum rc_proto protocol, u32 scancode,
			  struct ir_raw_event *events, unsigned int max)
{
	struct ir_raw_event *e = events;
	u32 raw, len;
	int ret;

	if (protocol == RC_PROTO_SONY12) {
		raw = (scancode & 0x7f) | ((scancode & 0x1f0000) >> 9);
		len = 12;
	} else if (protocol == RC_PROTO_SONY15) {
		raw = (scancode & 0x7f) | ((scancode & 0xff0000) >> 9);
		len = 15;
	} else {
		raw = (scancode & 0x7f) | ((scancode & 0x1f0000) >> 9) |
		       ((scancode & 0xff00) << 4);
		len = 20;
	}

	ret = ir_raw_gen_pl(&e, max, &ir_sony_timings, len, raw);
	if (ret < 0)
		return ret;

	return e - events;
}

static struct ir_raw_handler sony_handler = {
	.protocols	= RC_PROTO_BIT_SONY12 | RC_PROTO_BIT_SONY15 |
							RC_PROTO_BIT_SONY20,
	.decode		= ir_sony_decode,
	.encode		= ir_sony_encode,
};

static int __init ir_sony_decode_init(void)
{
	ir_raw_handler_register(&sony_handler);

	printk(KERN_INFO "IR Sony protocol handler initialized\n");
	return 0;
}

static void __exit ir_sony_decode_exit(void)
{
	ir_raw_handler_unregister(&sony_handler);
}

module_init(ir_sony_decode_init);
module_exit(ir_sony_decode_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
MODULE_DESCRIPTION("Sony IR protocol decoder");
OpenPOWER on IntegriCloud