1 /*
2 *
3 * some common structs and functions to handle infrared remotes via
4 * input layer ...
5 *
6 * (c) 2003 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
23 #include <linux/module.h>
24 #include <linux/string.h>
25 #include <linux/jiffies.h>
26 #include <media/ir-common.h>
27
28 /* -------------------------------------------------------------------------- */
29
30 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
31 MODULE_LICENSE("GPL");
32
33 static int repeat = 1;
34 module_param(repeat, int, 0444);
35 MODULE_PARM_DESC(repeat,"auto-repeat for IR keys (default: on)");
36
37 static int debug; /* debug level (0,1,2) */
38 module_param(debug, int, 0644);
39
40 #define dprintk(level, fmt, arg...) if (debug >= level) \
41 printk(KERN_DEBUG fmt , ## arg)
42
43 /* -------------------------------------------------------------------------- */
44
ir_input_key_event(struct input_dev * dev,struct ir_input_state * ir)45 static void ir_input_key_event(struct input_dev *dev, struct ir_input_state *ir)
46 {
47 if (KEY_RESERVED == ir->keycode) {
48 printk(KERN_INFO "%s: unknown key: key=0x%02x raw=0x%02x down=%d\n",
49 dev->name,ir->ir_key,ir->ir_raw,ir->keypressed);
50 return;
51 }
52 dprintk(1,"%s: key event code=%d down=%d\n",
53 dev->name,ir->keycode,ir->keypressed);
54 input_report_key(dev,ir->keycode,ir->keypressed);
55 input_sync(dev);
56 }
57
58 /* -------------------------------------------------------------------------- */
59
ir_input_init(struct input_dev * dev,struct ir_input_state * ir,int ir_type,IR_KEYTAB_TYPE * ir_codes)60 void ir_input_init(struct input_dev *dev, struct ir_input_state *ir,
61 int ir_type, IR_KEYTAB_TYPE *ir_codes)
62 {
63 int i;
64
65 ir->ir_type = ir_type;
66 if (ir_codes)
67 memcpy(ir->ir_codes, ir_codes, sizeof(ir->ir_codes));
68
69 dev->keycode = ir->ir_codes;
70 dev->keycodesize = sizeof(IR_KEYTAB_TYPE);
71 dev->keycodemax = IR_KEYTAB_SIZE;
72 for (i = 0; i < IR_KEYTAB_SIZE; i++)
73 set_bit(ir->ir_codes[i], dev->keybit);
74 clear_bit(0, dev->keybit);
75
76 set_bit(EV_KEY, dev->evbit);
77 if (repeat)
78 set_bit(EV_REP, dev->evbit);
79 }
80 EXPORT_SYMBOL_GPL(ir_input_init);
81
ir_input_nokey(struct input_dev * dev,struct ir_input_state * ir)82 void ir_input_nokey(struct input_dev *dev, struct ir_input_state *ir)
83 {
84 if (ir->keypressed) {
85 ir->keypressed = 0;
86 ir_input_key_event(dev,ir);
87 }
88 }
89 EXPORT_SYMBOL_GPL(ir_input_nokey);
90
ir_input_keydown(struct input_dev * dev,struct ir_input_state * ir,u32 ir_key,u32 ir_raw)91 void ir_input_keydown(struct input_dev *dev, struct ir_input_state *ir,
92 u32 ir_key, u32 ir_raw)
93 {
94 u32 keycode = IR_KEYCODE(ir->ir_codes, ir_key);
95
96 if (ir->keypressed && ir->keycode != keycode) {
97 ir->keypressed = 0;
98 ir_input_key_event(dev,ir);
99 }
100 if (!ir->keypressed) {
101 ir->ir_key = ir_key;
102 ir->ir_raw = ir_raw;
103 ir->keycode = keycode;
104 ir->keypressed = 1;
105 ir_input_key_event(dev,ir);
106 }
107 }
108 EXPORT_SYMBOL_GPL(ir_input_keydown);
109
110 /* -------------------------------------------------------------------------- */
111 /* extract mask bits out of data and pack them into the result */
ir_extract_bits(u32 data,u32 mask)112 u32 ir_extract_bits(u32 data, u32 mask)
113 {
114 u32 vbit = 1, value = 0;
115
116 do {
117 if (mask&1) {
118 if (data&1)
119 value |= vbit;
120 vbit<<=1;
121 }
122 data>>=1;
123 } while (mask>>=1);
124
125 return value;
126 }
127 EXPORT_SYMBOL_GPL(ir_extract_bits);
128
getbit(u32 * samples,int bit)129 static int inline getbit(u32 *samples, int bit)
130 {
131 return (samples[bit/32] & (1 << (31-(bit%32)))) ? 1 : 0;
132 }
133
134 /* sump raw samples for visual debugging ;) */
ir_dump_samples(u32 * samples,int count)135 int ir_dump_samples(u32 *samples, int count)
136 {
137 int i, bit, start;
138
139 printk(KERN_DEBUG "ir samples: ");
140 start = 0;
141 for (i = 0; i < count * 32; i++) {
142 bit = getbit(samples,i);
143 if (bit)
144 start = 1;
145 if (0 == start)
146 continue;
147 printk("%s", bit ? "#" : "_");
148 }
149 printk("\n");
150 return 0;
151 }
152 EXPORT_SYMBOL_GPL(ir_dump_samples);
153
154 /* decode raw samples, pulse distance coding used by NEC remotes */
ir_decode_pulsedistance(u32 * samples,int count,int low,int high)155 int ir_decode_pulsedistance(u32 *samples, int count, int low, int high)
156 {
157 int i,last,bit,len;
158 u32 curBit;
159 u32 value;
160
161 /* find start burst */
162 for (i = len = 0; i < count * 32; i++) {
163 bit = getbit(samples,i);
164 if (bit) {
165 len++;
166 } else {
167 if (len >= 29)
168 break;
169 len = 0;
170 }
171 }
172
173 /* start burst to short */
174 if (len < 29)
175 return 0xffffffff;
176
177 /* find start silence */
178 for (len = 0; i < count * 32; i++) {
179 bit = getbit(samples,i);
180 if (bit) {
181 break;
182 } else {
183 len++;
184 }
185 }
186
187 /* silence to short */
188 if (len < 7)
189 return 0xffffffff;
190
191 /* go decoding */
192 len = 0;
193 last = 1;
194 value = 0; curBit = 1;
195 for (; i < count * 32; i++) {
196 bit = getbit(samples,i);
197 if (last) {
198 if(bit) {
199 continue;
200 } else {
201 len = 1;
202 }
203 } else {
204 if (bit) {
205 if (len > (low + high) /2)
206 value |= curBit;
207 curBit <<= 1;
208 if (curBit == 1)
209 break;
210 } else {
211 len++;
212 }
213 }
214 last = bit;
215 }
216
217 return value;
218 }
219 EXPORT_SYMBOL_GPL(ir_decode_pulsedistance);
220
221 /* decode raw samples, biphase coding, used by rc5 for example */
ir_decode_biphase(u32 * samples,int count,int low,int high)222 int ir_decode_biphase(u32 *samples, int count, int low, int high)
223 {
224 int i,last,bit,len,flips;
225 u32 value;
226
227 /* find start bit (1) */
228 for (i = 0; i < 32; i++) {
229 bit = getbit(samples,i);
230 if (bit)
231 break;
232 }
233
234 /* go decoding */
235 len = 0;
236 flips = 0;
237 value = 1;
238 for (; i < count * 32; i++) {
239 if (len > high)
240 break;
241 if (flips > 1)
242 break;
243 last = bit;
244 bit = getbit(samples,i);
245 if (last == bit) {
246 len++;
247 continue;
248 }
249 if (len < low) {
250 len++;
251 flips++;
252 continue;
253 }
254 value <<= 1;
255 value |= bit;
256 flips = 0;
257 len = 1;
258 }
259 return value;
260 }
261 EXPORT_SYMBOL_GPL(ir_decode_biphase);
262
263 /* RC5 decoding stuff, moved from bttv-input.c to share it with
264 * saa7134 */
265
266 /* decode raw bit pattern to RC5 code */
ir_rc5_decode(unsigned int code)267 static u32 ir_rc5_decode(unsigned int code)
268 {
269 unsigned int org_code = code;
270 unsigned int pair;
271 unsigned int rc5 = 0;
272 int i;
273
274 for (i = 0; i < 14; ++i) {
275 pair = code & 0x3;
276 code >>= 2;
277
278 rc5 <<= 1;
279 switch (pair) {
280 case 0:
281 case 2:
282 break;
283 case 1:
284 rc5 |= 1;
285 break;
286 case 3:
287 dprintk(1, "ir-common: ir_rc5_decode(%x) bad code\n", org_code);
288 return 0;
289 }
290 }
291 dprintk(1, "ir-common: code=%x, rc5=%x, start=%x, toggle=%x, address=%x, "
292 "instr=%x\n", rc5, org_code, RC5_START(rc5),
293 RC5_TOGGLE(rc5), RC5_ADDR(rc5), RC5_INSTR(rc5));
294 return rc5;
295 }
296
ir_rc5_timer_end(unsigned long data)297 void ir_rc5_timer_end(unsigned long data)
298 {
299 struct card_ir *ir = (struct card_ir *)data;
300 struct timeval tv;
301 unsigned long current_jiffies, timeout;
302 u32 gap;
303 u32 rc5 = 0;
304
305 /* get time */
306 current_jiffies = jiffies;
307 do_gettimeofday(&tv);
308
309 /* avoid overflow with gap >1s */
310 if (tv.tv_sec - ir->base_time.tv_sec > 1) {
311 gap = 200000;
312 } else {
313 gap = 1000000 * (tv.tv_sec - ir->base_time.tv_sec) +
314 tv.tv_usec - ir->base_time.tv_usec;
315 }
316
317 /* signal we're ready to start a new code */
318 ir->active = 0;
319
320 /* Allow some timer jitter (RC5 is ~24ms anyway so this is ok) */
321 if (gap < 28000) {
322 dprintk(1, "ir-common: spurious timer_end\n");
323 return;
324 }
325
326 if (ir->last_bit < 20) {
327 /* ignore spurious codes (caused by light/other remotes) */
328 dprintk(1, "ir-common: short code: %x\n", ir->code);
329 } else {
330 ir->code = (ir->code << ir->shift_by) | 1;
331 rc5 = ir_rc5_decode(ir->code);
332
333 /* two start bits? */
334 if (RC5_START(rc5) != ir->start) {
335 dprintk(1, "ir-common: rc5 start bits invalid: %u\n", RC5_START(rc5));
336
337 /* right address? */
338 } else if (RC5_ADDR(rc5) == ir->addr) {
339 u32 toggle = RC5_TOGGLE(rc5);
340 u32 instr = RC5_INSTR(rc5);
341
342 /* Good code, decide if repeat/repress */
343 if (toggle != RC5_TOGGLE(ir->last_rc5) ||
344 instr != RC5_INSTR(ir->last_rc5)) {
345 dprintk(1, "ir-common: instruction %x, toggle %x\n", instr,
346 toggle);
347 ir_input_nokey(ir->dev, &ir->ir);
348 ir_input_keydown(ir->dev, &ir->ir, instr,
349 instr);
350 }
351
352 /* Set/reset key-up timer */
353 timeout = current_jiffies +
354 msecs_to_jiffies(ir->rc5_key_timeout);
355 mod_timer(&ir->timer_keyup, timeout);
356
357 /* Save code for repeat test */
358 ir->last_rc5 = rc5;
359 }
360 }
361 }
362 EXPORT_SYMBOL_GPL(ir_rc5_timer_end);
363
ir_rc5_timer_keyup(unsigned long data)364 void ir_rc5_timer_keyup(unsigned long data)
365 {
366 struct card_ir *ir = (struct card_ir *)data;
367
368 dprintk(1, "ir-common: key released\n");
369 ir_input_nokey(ir->dev, &ir->ir);
370 }
371 EXPORT_SYMBOL_GPL(ir_rc5_timer_keyup);
372