diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-20 12:37:45 -0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-20 12:37:45 -0400 |
commit | fb091be08d1acf184e8801dfdcace6e0cb19b1fe (patch) | |
tree | cbd0c4200fd8628d592167589ca790e36fc4ae26 /drivers/media/IR/ir-rc5-decoder.c | |
parent | bd7fc2f2d807fdb254f7efc542f8eec3f23e289e (diff) | |
parent | e8d0416796d43a950ec7b65629e53419b2e22453 (diff) |
Merge branch 'v4l_for_2.6.35' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
* 'v4l_for_2.6.35' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (534 commits)
V4L/DVB (13554a): v4l: Use the video_drvdata function in drivers
V4L/DVB: vivi and mem2mem_testdev need slab.h to build
V4L/DVB: tm6000: bugfix image position
V4L/DVB: IR/imon: remove dead IMON_KEY_RELEASE_OFFSET
V4L/DVB: tm6000: README - add vbi
V4L/DVB: Fix unlock logic at medusa_video_init
V4L/DVB: fix dvb frontend lockup
V4L/DVB: s2255drv: remove dead code
V4L/DVB: s2255drv: return if vdev not found
V4L/DVB: ov511: cleanup: remove unneeded null check
V4L/DVB: media/mem2mem: dereferencing free memory
V4L/DVB: media/IR: Add missing include file to rc-map.c
V4L/DVB: dvb/stv6110x: cleanup error handling
V4L/DVB: ngene: Add lgdt3303 and mt2131 deps to Kconfig
V4L/DVB: ngene: start separating out DVB functions into separate file
V4L/DVB: ngene: split out card specific code into a separate file
V4L/DVB: ngene: split out i2c code into a separate file
V4L/DVB: ngene: add initial support for digital side of Avermedia m780
V4L/DVB: ngene: properly support boards where channel 0 isn't a TS input
V4L-DVB: ngene: make sure that tuner headers are included
...
Diffstat (limited to 'drivers/media/IR/ir-rc5-decoder.c')
-rw-r--r-- | drivers/media/IR/ir-rc5-decoder.c | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/drivers/media/IR/ir-rc5-decoder.c b/drivers/media/IR/ir-rc5-decoder.c new file mode 100644 index 000000000000..23cdb1b1a3bc --- /dev/null +++ b/drivers/media/IR/ir-rc5-decoder.c | |||
@@ -0,0 +1,324 @@ | |||
1 | /* ir-rc5-decoder.c - handle RC5(x) 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 | /* | ||
16 | * This code handles 14 bits RC5 protocols and 20 bits RC5x protocols. | ||
17 | * There are other variants that use a different number of bits. | ||
18 | * This is currently unsupported. | ||
19 | * It considers a carrier of 36 kHz, with a total of 14/20 bits, where | ||
20 | * the first two bits are start bits, and a third one is a filing bit | ||
21 | */ | ||
22 | |||
23 | #include "ir-core-priv.h" | ||
24 | |||
25 | #define RC5_NBITS 14 | ||
26 | #define RC5X_NBITS 20 | ||
27 | #define CHECK_RC5X_NBITS 8 | ||
28 | #define RC5_UNIT 888888 /* ns */ | ||
29 | #define RC5_BIT_START (1 * RC5_UNIT) | ||
30 | #define RC5_BIT_END (1 * RC5_UNIT) | ||
31 | #define RC5X_SPACE (4 * RC5_UNIT) | ||
32 | |||
33 | /* Used to register rc5_decoder clients */ | ||
34 | static LIST_HEAD(decoder_list); | ||
35 | static DEFINE_SPINLOCK(decoder_lock); | ||
36 | |||
37 | enum rc5_state { | ||
38 | STATE_INACTIVE, | ||
39 | STATE_BIT_START, | ||
40 | STATE_BIT_END, | ||
41 | STATE_CHECK_RC5X, | ||
42 | STATE_FINISHED, | ||
43 | }; | ||
44 | |||
45 | struct decoder_data { | ||
46 | struct list_head list; | ||
47 | struct ir_input_dev *ir_dev; | ||
48 | int enabled:1; | ||
49 | |||
50 | /* State machine control */ | ||
51 | enum rc5_state state; | ||
52 | u32 rc5_bits; | ||
53 | struct ir_raw_event prev_ev; | ||
54 | unsigned count; | ||
55 | unsigned wanted_bits; | ||
56 | }; | ||
57 | |||
58 | |||
59 | /** | ||
60 | * get_decoder_data() - gets decoder data | ||
61 | * @input_dev: input device | ||
62 | * | ||
63 | * Returns the struct decoder_data that corresponds to a device | ||
64 | */ | ||
65 | |||
66 | static struct decoder_data *get_decoder_data(struct ir_input_dev *ir_dev) | ||
67 | { | ||
68 | struct decoder_data *data = NULL; | ||
69 | |||
70 | spin_lock(&decoder_lock); | ||
71 | list_for_each_entry(data, &decoder_list, list) { | ||
72 | if (data->ir_dev == ir_dev) | ||
73 | break; | ||
74 | } | ||
75 | spin_unlock(&decoder_lock); | ||
76 | return data; | ||
77 | } | ||
78 | |||
79 | static ssize_t store_enabled(struct device *d, | ||
80 | struct device_attribute *mattr, | ||
81 | const char *buf, | ||
82 | size_t len) | ||
83 | { | ||
84 | unsigned long value; | ||
85 | struct ir_input_dev *ir_dev = dev_get_drvdata(d); | ||
86 | struct decoder_data *data = get_decoder_data(ir_dev); | ||
87 | |||
88 | if (!data) | ||
89 | return -EINVAL; | ||
90 | |||
91 | if (strict_strtoul(buf, 10, &value) || value > 1) | ||
92 | return -EINVAL; | ||
93 | |||
94 | data->enabled = value; | ||
95 | |||
96 | return len; | ||
97 | } | ||
98 | |||
99 | static ssize_t show_enabled(struct device *d, | ||
100 | struct device_attribute *mattr, char *buf) | ||
101 | { | ||
102 | struct ir_input_dev *ir_dev = dev_get_drvdata(d); | ||
103 | struct decoder_data *data = get_decoder_data(ir_dev); | ||
104 | |||
105 | if (!data) | ||
106 | return -EINVAL; | ||
107 | |||
108 | if (data->enabled) | ||
109 | return sprintf(buf, "1\n"); | ||
110 | else | ||
111 | return sprintf(buf, "0\n"); | ||
112 | } | ||
113 | |||
114 | static DEVICE_ATTR(enabled, S_IRUGO | S_IWUSR, show_enabled, store_enabled); | ||
115 | |||
116 | static struct attribute *decoder_attributes[] = { | ||
117 | &dev_attr_enabled.attr, | ||
118 | NULL | ||
119 | }; | ||
120 | |||
121 | static struct attribute_group decoder_attribute_group = { | ||
122 | .name = "rc5_decoder", | ||
123 | .attrs = decoder_attributes, | ||
124 | }; | ||
125 | |||
126 | /** | ||
127 | * ir_rc5_decode() - Decode one RC-5 pulse or space | ||
128 | * @input_dev: the struct input_dev descriptor of the device | ||
129 | * @ev: the struct ir_raw_event descriptor of the pulse/space | ||
130 | * | ||
131 | * This function returns -EINVAL if the pulse violates the state machine | ||
132 | */ | ||
133 | static int ir_rc5_decode(struct input_dev *input_dev, struct ir_raw_event ev) | ||
134 | { | ||
135 | struct decoder_data *data; | ||
136 | struct ir_input_dev *ir_dev = input_get_drvdata(input_dev); | ||
137 | u8 toggle; | ||
138 | u32 scancode; | ||
139 | |||
140 | data = get_decoder_data(ir_dev); | ||
141 | if (!data) | ||
142 | return -EINVAL; | ||
143 | |||
144 | if (!data->enabled) | ||
145 | return 0; | ||
146 | |||
147 | if (IS_RESET(ev)) { | ||
148 | data->state = STATE_INACTIVE; | ||
149 | return 0; | ||
150 | } | ||
151 | |||
152 | if (!geq_margin(ev.duration, RC5_UNIT, RC5_UNIT / 2)) | ||
153 | goto out; | ||
154 | |||
155 | again: | ||
156 | IR_dprintk(2, "RC5(x) decode started at state %i (%uus %s)\n", | ||
157 | data->state, TO_US(ev.duration), TO_STR(ev.pulse)); | ||
158 | |||
159 | if (!geq_margin(ev.duration, RC5_UNIT, RC5_UNIT / 2)) | ||
160 | return 0; | ||
161 | |||
162 | switch (data->state) { | ||
163 | |||
164 | case STATE_INACTIVE: | ||
165 | if (!ev.pulse) | ||
166 | break; | ||
167 | |||
168 | data->state = STATE_BIT_START; | ||
169 | data->count = 1; | ||
170 | /* We just need enough bits to get to STATE_CHECK_RC5X */ | ||
171 | data->wanted_bits = RC5X_NBITS; | ||
172 | decrease_duration(&ev, RC5_BIT_START); | ||
173 | goto again; | ||
174 | |||
175 | case STATE_BIT_START: | ||
176 | if (!eq_margin(ev.duration, RC5_BIT_START, RC5_UNIT / 2)) | ||
177 | break; | ||
178 | |||
179 | data->rc5_bits <<= 1; | ||
180 | if (!ev.pulse) | ||
181 | data->rc5_bits |= 1; | ||
182 | data->count++; | ||
183 | data->prev_ev = ev; | ||
184 | data->state = STATE_BIT_END; | ||
185 | return 0; | ||
186 | |||
187 | case STATE_BIT_END: | ||
188 | if (!is_transition(&ev, &data->prev_ev)) | ||
189 | break; | ||
190 | |||
191 | if (data->count == data->wanted_bits) | ||
192 | data->state = STATE_FINISHED; | ||
193 | else if (data->count == CHECK_RC5X_NBITS) | ||
194 | data->state = STATE_CHECK_RC5X; | ||
195 | else | ||
196 | data->state = STATE_BIT_START; | ||
197 | |||
198 | decrease_duration(&ev, RC5_BIT_END); | ||
199 | goto again; | ||
200 | |||
201 | case STATE_CHECK_RC5X: | ||
202 | if (!ev.pulse && geq_margin(ev.duration, RC5X_SPACE, RC5_UNIT / 2)) { | ||
203 | /* RC5X */ | ||
204 | data->wanted_bits = RC5X_NBITS; | ||
205 | decrease_duration(&ev, RC5X_SPACE); | ||
206 | } else { | ||
207 | /* RC5 */ | ||
208 | data->wanted_bits = RC5_NBITS; | ||
209 | } | ||
210 | data->state = STATE_BIT_START; | ||
211 | goto again; | ||
212 | |||
213 | case STATE_FINISHED: | ||
214 | if (ev.pulse) | ||
215 | break; | ||
216 | |||
217 | if (data->wanted_bits == RC5X_NBITS) { | ||
218 | /* RC5X */ | ||
219 | u8 xdata, command, system; | ||
220 | xdata = (data->rc5_bits & 0x0003F) >> 0; | ||
221 | command = (data->rc5_bits & 0x00FC0) >> 6; | ||
222 | system = (data->rc5_bits & 0x1F000) >> 12; | ||
223 | toggle = (data->rc5_bits & 0x20000) ? 1 : 0; | ||
224 | command += (data->rc5_bits & 0x01000) ? 0 : 0x40; | ||
225 | scancode = system << 16 | command << 8 | xdata; | ||
226 | |||
227 | IR_dprintk(1, "RC5X scancode 0x%06x (toggle: %u)\n", | ||
228 | scancode, toggle); | ||
229 | |||
230 | } else { | ||
231 | /* RC5 */ | ||
232 | u8 command, system; | ||
233 | command = (data->rc5_bits & 0x0003F) >> 0; | ||
234 | system = (data->rc5_bits & 0x007C0) >> 6; | ||
235 | toggle = (data->rc5_bits & 0x00800) ? 1 : 0; | ||
236 | command += (data->rc5_bits & 0x01000) ? 0 : 0x40; | ||
237 | scancode = system << 8 | command; | ||
238 | |||
239 | IR_dprintk(1, "RC5 scancode 0x%04x (toggle: %u)\n", | ||
240 | scancode, toggle); | ||
241 | } | ||
242 | |||
243 | ir_keydown(input_dev, scancode, toggle); | ||
244 | data->state = STATE_INACTIVE; | ||
245 | return 0; | ||
246 | } | ||
247 | |||
248 | out: | ||
249 | IR_dprintk(1, "RC5(x) decode failed at state %i (%uus %s)\n", | ||
250 | data->state, TO_US(ev.duration), TO_STR(ev.pulse)); | ||
251 | data->state = STATE_INACTIVE; | ||
252 | return -EINVAL; | ||
253 | } | ||
254 | |||
255 | static int ir_rc5_register(struct input_dev *input_dev) | ||
256 | { | ||
257 | struct ir_input_dev *ir_dev = input_get_drvdata(input_dev); | ||
258 | struct decoder_data *data; | ||
259 | int rc; | ||
260 | |||
261 | rc = sysfs_create_group(&ir_dev->dev.kobj, &decoder_attribute_group); | ||
262 | if (rc < 0) | ||
263 | return rc; | ||
264 | |||
265 | data = kzalloc(sizeof(*data), GFP_KERNEL); | ||
266 | if (!data) { | ||
267 | sysfs_remove_group(&ir_dev->dev.kobj, &decoder_attribute_group); | ||
268 | return -ENOMEM; | ||
269 | } | ||
270 | |||
271 | data->ir_dev = ir_dev; | ||
272 | data->enabled = 1; | ||
273 | |||
274 | spin_lock(&decoder_lock); | ||
275 | list_add_tail(&data->list, &decoder_list); | ||
276 | spin_unlock(&decoder_lock); | ||
277 | |||
278 | return 0; | ||
279 | } | ||
280 | |||
281 | static int ir_rc5_unregister(struct input_dev *input_dev) | ||
282 | { | ||
283 | struct ir_input_dev *ir_dev = input_get_drvdata(input_dev); | ||
284 | static struct decoder_data *data; | ||
285 | |||
286 | data = get_decoder_data(ir_dev); | ||
287 | if (!data) | ||
288 | return 0; | ||
289 | |||
290 | sysfs_remove_group(&ir_dev->dev.kobj, &decoder_attribute_group); | ||
291 | |||
292 | spin_lock(&decoder_lock); | ||
293 | list_del(&data->list); | ||
294 | spin_unlock(&decoder_lock); | ||
295 | |||
296 | return 0; | ||
297 | } | ||
298 | |||
299 | static struct ir_raw_handler rc5_handler = { | ||
300 | .decode = ir_rc5_decode, | ||
301 | .raw_register = ir_rc5_register, | ||
302 | .raw_unregister = ir_rc5_unregister, | ||
303 | }; | ||
304 | |||
305 | static int __init ir_rc5_decode_init(void) | ||
306 | { | ||
307 | ir_raw_handler_register(&rc5_handler); | ||
308 | |||
309 | printk(KERN_INFO "IR RC5(x) protocol handler initialized\n"); | ||
310 | return 0; | ||
311 | } | ||
312 | |||
313 | static void __exit ir_rc5_decode_exit(void) | ||
314 | { | ||
315 | ir_raw_handler_unregister(&rc5_handler); | ||
316 | } | ||
317 | |||
318 | module_init(ir_rc5_decode_init); | ||
319 | module_exit(ir_rc5_decode_exit); | ||
320 | |||
321 | MODULE_LICENSE("GPL"); | ||
322 | MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>"); | ||
323 | MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)"); | ||
324 | MODULE_DESCRIPTION("RC5(x) IR protocol decoder"); | ||