arm: tegra: enterprise: Filling regulator supply info
[linux-2.6.git] / drivers / media / rc / ir-jvc-decoder.c
1 /* ir-jvc-decoder.c - handle JVC 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 JVC_NBITS               16              /* dev(8) + func(8) */
19 #define JVC_UNIT                525000          /* ns */
20 #define JVC_HEADER_PULSE        (16 * JVC_UNIT) /* lack of header -> repeat */
21 #define JVC_HEADER_SPACE        (8  * JVC_UNIT)
22 #define JVC_BIT_PULSE           (1  * JVC_UNIT)
23 #define JVC_BIT_0_SPACE         (1  * JVC_UNIT)
24 #define JVC_BIT_1_SPACE         (3  * JVC_UNIT)
25 #define JVC_TRAILER_PULSE       (1  * JVC_UNIT)
26 #define JVC_TRAILER_SPACE       (35 * JVC_UNIT)
27
28 enum jvc_state {
29         STATE_INACTIVE,
30         STATE_HEADER_SPACE,
31         STATE_BIT_PULSE,
32         STATE_BIT_SPACE,
33         STATE_TRAILER_PULSE,
34         STATE_TRAILER_SPACE,
35         STATE_CHECK_REPEAT,
36 };
37
38 /**
39  * ir_jvc_decode() - Decode one JVC pulse or space
40  * @dev:        the struct rc_dev descriptor of the device
41  * @duration:   the struct ir_raw_event descriptor of the pulse/space
42  *
43  * This function returns -EINVAL if the pulse violates the state machine
44  */
45 static int ir_jvc_decode(struct rc_dev *dev, struct ir_raw_event ev)
46 {
47         struct jvc_dec *data = &dev->raw->jvc;
48
49         if (!(dev->raw->enabled_protocols & RC_TYPE_JVC))
50                 return 0;
51
52         if (!is_timing_event(ev)) {
53                 if (ev.reset)
54                         data->state = STATE_INACTIVE;
55                 return 0;
56         }
57
58         if (!geq_margin(ev.duration, JVC_UNIT, JVC_UNIT / 2))
59                 goto out;
60
61         IR_dprintk(2, "JVC decode started at state %d (%uus %s)\n",
62                    data->state, TO_US(ev.duration), TO_STR(ev.pulse));
63
64 again:
65         switch (data->state) {
66
67         case STATE_INACTIVE:
68                 if (!ev.pulse)
69                         break;
70
71                 if (!eq_margin(ev.duration, JVC_HEADER_PULSE, JVC_UNIT / 2))
72                         break;
73
74                 data->count = 0;
75                 data->first = true;
76                 data->toggle = !data->toggle;
77                 data->state = STATE_HEADER_SPACE;
78                 return 0;
79
80         case STATE_HEADER_SPACE:
81                 if (ev.pulse)
82                         break;
83
84                 if (!eq_margin(ev.duration, JVC_HEADER_SPACE, JVC_UNIT / 2))
85                         break;
86
87                 data->state = STATE_BIT_PULSE;
88                 return 0;
89
90         case STATE_BIT_PULSE:
91                 if (!ev.pulse)
92                         break;
93
94                 if (!eq_margin(ev.duration, JVC_BIT_PULSE, JVC_UNIT / 2))
95                         break;
96
97                 data->state = STATE_BIT_SPACE;
98                 return 0;
99
100         case STATE_BIT_SPACE:
101                 if (ev.pulse)
102                         break;
103
104                 data->bits <<= 1;
105                 if (eq_margin(ev.duration, JVC_BIT_1_SPACE, JVC_UNIT / 2)) {
106                         data->bits |= 1;
107                         decrease_duration(&ev, JVC_BIT_1_SPACE);
108                 } else if (eq_margin(ev.duration, JVC_BIT_0_SPACE, JVC_UNIT / 2))
109                         decrease_duration(&ev, JVC_BIT_0_SPACE);
110                 else
111                         break;
112                 data->count++;
113
114                 if (data->count == JVC_NBITS)
115                         data->state = STATE_TRAILER_PULSE;
116                 else
117                         data->state = STATE_BIT_PULSE;
118                 return 0;
119
120         case STATE_TRAILER_PULSE:
121                 if (!ev.pulse)
122                         break;
123
124                 if (!eq_margin(ev.duration, JVC_TRAILER_PULSE, JVC_UNIT / 2))
125                         break;
126
127                 data->state = STATE_TRAILER_SPACE;
128                 return 0;
129
130         case STATE_TRAILER_SPACE:
131                 if (ev.pulse)
132                         break;
133
134                 if (!geq_margin(ev.duration, JVC_TRAILER_SPACE, JVC_UNIT / 2))
135                         break;
136
137                 if (data->first) {
138                         u32 scancode;
139                         scancode = (bitrev8((data->bits >> 8) & 0xff) << 8) |
140                                    (bitrev8((data->bits >> 0) & 0xff) << 0);
141                         IR_dprintk(1, "JVC scancode 0x%04x\n", scancode);
142                         rc_keydown(dev, scancode, data->toggle);
143                         data->first = false;
144                         data->old_bits = data->bits;
145                 } else if (data->bits == data->old_bits) {
146                         IR_dprintk(1, "JVC repeat\n");
147                         rc_repeat(dev);
148                 } else {
149                         IR_dprintk(1, "JVC invalid repeat msg\n");
150                         break;
151                 }
152
153                 data->count = 0;
154                 data->state = STATE_CHECK_REPEAT;
155                 return 0;
156
157         case STATE_CHECK_REPEAT:
158                 if (!ev.pulse)
159                         break;
160
161                 if (eq_margin(ev.duration, JVC_HEADER_PULSE, JVC_UNIT / 2))
162                         data->state = STATE_INACTIVE;
163   else
164                         data->state = STATE_BIT_PULSE;
165                 goto again;
166         }
167
168 out:
169         IR_dprintk(1, "JVC decode failed at state %d (%uus %s)\n",
170                    data->state, TO_US(ev.duration), TO_STR(ev.pulse));
171         data->state = STATE_INACTIVE;
172         return -EINVAL;
173 }
174
175 static struct ir_raw_handler jvc_handler = {
176         .protocols      = RC_TYPE_JVC,
177         .decode         = ir_jvc_decode,
178 };
179
180 static int __init ir_jvc_decode_init(void)
181 {
182         ir_raw_handler_register(&jvc_handler);
183
184         printk(KERN_INFO "IR JVC protocol handler initialized\n");
185         return 0;
186 }
187
188 static void __exit ir_jvc_decode_exit(void)
189 {
190         ir_raw_handler_unregister(&jvc_handler);
191 }
192
193 module_init(ir_jvc_decode_init);
194 module_exit(ir_jvc_decode_exit);
195
196 MODULE_LICENSE("GPL");
197 MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
198 MODULE_DESCRIPTION("JVC IR protocol decoder");