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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/media/IR/
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#include "ir-core-priv.h"
28
29/* -------------------------------------------------------------------------- */
30
31MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
32MODULE_LICENSE("GPL");
33
34static int repeat = 1;
35module_param(repeat, int, 0444);
36MODULE_PARM_DESC(repeat,"auto-repeat for IR keys (default: on)");
37
38/* -------------------------------------------------------------------------- */
39
40static void ir_input_key_event(struct input_dev *dev, struct ir_input_state *ir)
41{
42	if (KEY_RESERVED == ir->keycode) {
43		printk(KERN_INFO "%s: unknown key: key=0x%02x down=%d\n",
44		       dev->name, ir->ir_key, ir->keypressed);
45		return;
46	}
47	IR_dprintk(1,"%s: key event code=%d down=%d\n",
48		dev->name,ir->keycode,ir->keypressed);
49	input_report_key(dev,ir->keycode,ir->keypressed);
50	input_sync(dev);
51}
52
53/* -------------------------------------------------------------------------- */
54
55int ir_input_init(struct input_dev *dev, struct ir_input_state *ir,
56		  const u64 ir_type)
57{
58	ir->ir_type = ir_type;
59
60	if (repeat)
61		set_bit(EV_REP, dev->evbit);
62
63	return 0;
64}
65EXPORT_SYMBOL_GPL(ir_input_init);
66
67
68void ir_input_nokey(struct input_dev *dev, struct ir_input_state *ir)
69{
70	if (ir->keypressed) {
71		ir->keypressed = 0;
72		ir_input_key_event(dev,ir);
73	}
74}
75EXPORT_SYMBOL_GPL(ir_input_nokey);
76
77void ir_input_keydown(struct input_dev *dev, struct ir_input_state *ir,
78		      u32 ir_key)
79{
80	u32 keycode = ir_g_keycode_from_table(dev, ir_key);
81
82	if (ir->keypressed && ir->keycode != keycode) {
83		ir->keypressed = 0;
84		ir_input_key_event(dev,ir);
85	}
86	if (!ir->keypressed) {
87		ir->ir_key  = ir_key;
88		ir->keycode = keycode;
89		ir->keypressed = 1;
90		ir_input_key_event(dev,ir);
91	}
92}
93EXPORT_SYMBOL_GPL(ir_input_keydown);
94
95/* -------------------------------------------------------------------------- */
96/* extract mask bits out of data and pack them into the result */
97u32 ir_extract_bits(u32 data, u32 mask)
98{
99	u32 vbit = 1, value = 0;
100
101	do {
102	    if (mask&1) {
103		if (data&1)
104			value |= vbit;
105		vbit<<=1;
106	    }
107	    data>>=1;
108	} while (mask>>=1);
109
110	return value;
111}
112EXPORT_SYMBOL_GPL(ir_extract_bits);
113
114static int inline getbit(u32 *samples, int bit)
115{
116	return (samples[bit/32] & (1 << (31-(bit%32)))) ? 1 : 0;
117}
118
119/* sump raw samples for visual debugging ;) */
120int ir_dump_samples(u32 *samples, int count)
121{
122	int i, bit, start;
123
124	printk(KERN_DEBUG "ir samples: ");
125	start = 0;
126	for (i = 0; i < count * 32; i++) {
127		bit = getbit(samples,i);
128		if (bit)
129			start = 1;
130		if (0 == start)
131			continue;
132		printk("%s", bit ? "#" : "_");
133	}
134	printk("\n");
135	return 0;
136}
137EXPORT_SYMBOL_GPL(ir_dump_samples);
138
139/* decode raw samples, pulse distance coding used by NEC remotes */
140int ir_decode_pulsedistance(u32 *samples, int count, int low, int high)
141{
142	int i,last,bit,len;
143	u32 curBit;
144	u32 value;
145
146	/* find start burst */
147	for (i = len = 0; i < count * 32; i++) {
148		bit = getbit(samples,i);
149		if (bit) {
150			len++;
151		} else {
152			if (len >= 29)
153				break;
154			len = 0;
155		}
156	}
157
158	/* start burst to short */
159	if (len < 29)
160		return 0xffffffff;
161
162	/* find start silence */
163	for (len = 0; i < count * 32; i++) {
164		bit = getbit(samples,i);
165		if (bit) {
166			break;
167		} else {
168			len++;
169		}
170	}
171
172	/* silence to short */
173	if (len < 7)
174		return 0xffffffff;
175
176	/* go decoding */
177	len   = 0;
178	last = 1;
179	value = 0; curBit = 1;
180	for (; i < count * 32; i++) {
181		bit  = getbit(samples,i);
182		if (last) {
183			if(bit) {
184				continue;
185			} else {
186				len = 1;
187			}
188		} else {
189			if (bit) {
190				if (len > (low + high) /2)
191					value |= curBit;
192				curBit <<= 1;
193				if (curBit == 1)
194					break;
195			} else {
196				len++;
197			}
198		}
199		last = bit;
200	}
201
202	return value;
203}
204EXPORT_SYMBOL_GPL(ir_decode_pulsedistance);
205
206/* decode raw samples, biphase coding, used by rc5 for example */
207int ir_decode_biphase(u32 *samples, int count, int low, int high)
208{
209	int i,last,bit,len,flips;
210	u32 value;
211
212	/* find start bit (1) */
213	for (i = 0; i < 32; i++) {
214		bit = getbit(samples,i);
215		if (bit)
216			break;
217	}
218
219	/* go decoding */
220	len   = 0;
221	flips = 0;
222	value = 1;
223	for (; i < count * 32; i++) {
224		if (len > high)
225			break;
226		if (flips > 1)
227			break;
228		last = bit;
229		bit  = getbit(samples,i);
230		if (last == bit) {
231			len++;
232			continue;
233		}
234		if (len < low) {
235			len++;
236			flips++;
237			continue;
238		}
239		value <<= 1;
240		value |= bit;
241		flips = 0;
242		len   = 1;
243	}
244	return value;
245}
246EXPORT_SYMBOL_GPL(ir_decode_biphase);
247
248/* RC5 decoding stuff, moved from bttv-input.c to share it with
249 * saa7134 */
250
251/* decode raw bit pattern to RC5 code */
252u32 ir_rc5_decode(unsigned int code)
253{
254	unsigned int org_code = code;
255	unsigned int pair;
256	unsigned int rc5 = 0;
257	int i;
258
259	for (i = 0; i < 14; ++i) {
260		pair = code & 0x3;
261		code >>= 2;
262
263		rc5 <<= 1;
264		switch (pair) {
265		case 0:
266		case 2:
267			break;
268		case 1:
269			rc5 |= 1;
270			break;
271		case 3:
272			IR_dprintk(1, "ir-common: ir_rc5_decode(%x) bad code\n", org_code);
273			return 0;
274		}
275	}
276	IR_dprintk(1, "ir-common: code=%x, rc5=%x, start=%x, toggle=%x, address=%x, "
277		"instr=%x\n", rc5, org_code, RC5_START(rc5),
278		RC5_TOGGLE(rc5), RC5_ADDR(rc5), RC5_INSTR(rc5));
279	return rc5;
280}
281EXPORT_SYMBOL_GPL(ir_rc5_decode);
282
283void ir_rc5_timer_end(unsigned long data)
284{
285	struct card_ir *ir = (struct card_ir *)data;
286	struct timeval tv;
287	unsigned long current_jiffies, timeout;
288	u32 gap;
289	u32 rc5 = 0;
290
291	/* get time */
292	current_jiffies = jiffies;
293	do_gettimeofday(&tv);
294
295	/* avoid overflow with gap >1s */
296	if (tv.tv_sec - ir->base_time.tv_sec > 1) {
297		gap = 200000;
298	} else {
299		gap = 1000000 * (tv.tv_sec - ir->base_time.tv_sec) +
300		    tv.tv_usec - ir->base_time.tv_usec;
301	}
302
303	/* signal we're ready to start a new code */
304	ir->active = 0;
305
306	/* Allow some timer jitter (RC5 is ~24ms anyway so this is ok) */
307	if (gap < 28000) {
308		IR_dprintk(1, "ir-common: spurious timer_end\n");
309		return;
310	}
311
312	if (ir->last_bit < 20) {
313		/* ignore spurious codes (caused by light/other remotes) */
314		IR_dprintk(1, "ir-common: short code: %x\n", ir->code);
315	} else {
316		ir->code = (ir->code << ir->shift_by) | 1;
317		rc5 = ir_rc5_decode(ir->code);
318
319		/* two start bits? */
320		if (RC5_START(rc5) != ir->start) {
321			IR_dprintk(1, "ir-common: rc5 start bits invalid: %u\n", RC5_START(rc5));
322
323			/* right address? */
324		} else if (RC5_ADDR(rc5) == ir->addr) {
325			u32 toggle = RC5_TOGGLE(rc5);
326			u32 instr = RC5_INSTR(rc5);
327
328			/* Good code, decide if repeat/repress */
329			if (toggle != RC5_TOGGLE(ir->last_rc5) ||
330			    instr != RC5_INSTR(ir->last_rc5)) {
331				IR_dprintk(1, "ir-common: instruction %x, toggle %x\n", instr,
332					toggle);
333				ir_input_nokey(ir->dev, &ir->ir);
334				ir_input_keydown(ir->dev, &ir->ir, instr);
335			}
336
337			/* Set/reset key-up timer */
338			timeout = current_jiffies +
339				  msecs_to_jiffies(ir->rc5_key_timeout);
340			mod_timer(&ir->timer_keyup, timeout);
341
342			/* Save code for repeat test */
343			ir->last_rc5 = rc5;
344		}
345	}
346}
347EXPORT_SYMBOL_GPL(ir_rc5_timer_end);
348
349void ir_rc5_timer_keyup(unsigned long data)
350{
351	struct card_ir *ir = (struct card_ir *)data;
352
353	IR_dprintk(1, "ir-common: key released\n");
354	ir_input_nokey(ir->dev, &ir->ir);
355}
356EXPORT_SYMBOL_GPL(ir_rc5_timer_keyup);
357