1 /*
2   handle em28xx IR remotes via linux kernel input layer.
3 
4    Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it>
5 		      Markus Rechberger <mrechberger@gmail.com>
6 		      Mauro Carvalho Chehab <mchehab@infradead.org>
7 		      Sascha Sommer <saschasommer@freenet.de>
8 
9   This program is free software; you can redistribute it and/or modify
10   it under the terms of the GNU General Public License as published by
11   the Free Software Foundation; either version 2 of the License, or
12   (at your option) any later version.
13 
14   This program is distributed in the hope that it will be useful,
15   but WITHOUT ANY WARRANTY; without even the implied warranty of
16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License for more details.
18 
19   You should have received a copy of the GNU General Public License
20   along with this program; if not, write to the Free Software
21   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22  */
23 
24 #include "em28xx.h"
25 
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/delay.h>
29 #include <linux/interrupt.h>
30 #include <linux/usb.h>
31 #include <linux/slab.h>
32 #include <linux/bitrev.h>
33 
34 #define EM28XX_SNAPSHOT_KEY				KEY_CAMERA
35 #define EM28XX_BUTTONS_DEBOUNCED_QUERY_INTERVAL		500 /* [ms] */
36 #define EM28XX_BUTTONS_VOLATILE_QUERY_INTERVAL		100 /* [ms] */
37 
38 static unsigned int ir_debug;
39 module_param(ir_debug, int, 0644);
40 MODULE_PARM_DESC(ir_debug, "enable debug messages [IR]");
41 
42 #define MODULE_NAME "em28xx"
43 
44 #define dprintk( fmt, arg...) do {					\
45 	if (ir_debug)							\
46 		dev_printk(KERN_DEBUG, &ir->dev->intf->dev,		\
47 			   "input: %s: " fmt, __func__, ## arg);	\
48 } while (0)
49 
50 /**********************************************************
51  Polling structure used by em28xx IR's
52  **********************************************************/
53 
54 struct em28xx_ir_poll_result {
55 	unsigned int toggle_bit:1;
56 	unsigned int read_count:7;
57 
58 	enum rc_proto protocol;
59 	u32 scancode;
60 };
61 
62 struct em28xx_IR {
63 	struct em28xx *dev;
64 	struct rc_dev *rc;
65 	char name[32];
66 	char phys[32];
67 
68 	/* poll decoder */
69 	int polling;
70 	struct delayed_work work;
71 	unsigned int full_code:1;
72 	unsigned int last_readcount;
73 	u64 rc_proto;
74 
75 	struct i2c_client *i2c_client;
76 
77 	int  (*get_key_i2c)(struct i2c_client *ir, enum rc_proto *protocol,
78 			    u32 *scancode);
79 	int  (*get_key)(struct em28xx_IR *, struct em28xx_ir_poll_result *);
80 };
81 
82 /**********************************************************
83  I2C IR based get keycodes - should be used with ir-kbd-i2c
84  **********************************************************/
85 
86 static int em28xx_get_key_terratec(struct i2c_client *i2c_dev,
87 				   enum rc_proto *protocol, u32 *scancode)
88 {
89 	unsigned char b;
90 
91 	/* poll IR chip */
92 	if (1 != i2c_master_recv(i2c_dev, &b, 1))
93 		return -EIO;
94 
95 	/* it seems that 0xFE indicates that a button is still hold
96 	   down, while 0xff indicates that no button is hold down. */
97 
98 	if (b == 0xff)
99 		return 0;
100 
101 	if (b == 0xfe)
102 		/* keep old data */
103 		return 1;
104 
105 	*protocol = RC_PROTO_UNKNOWN;
106 	*scancode = b;
107 	return 1;
108 }
109 
110 static int em28xx_get_key_em_haup(struct i2c_client *i2c_dev,
111 				  enum rc_proto *protocol, u32 *scancode)
112 {
113 	unsigned char buf[2];
114 	int size;
115 
116 	/* poll IR chip */
117 	size = i2c_master_recv(i2c_dev, buf, sizeof(buf));
118 
119 	if (size != 2)
120 		return -EIO;
121 
122 	/* Does eliminate repeated parity code */
123 	if (buf[1] == 0xff)
124 		return 0;
125 
126 	/*
127 	 * Rearranges bits to the right order.
128 	 * The bit order were determined experimentally by using
129 	 * The original Hauppauge Grey IR and another RC5 that uses addr=0x08
130 	 * The RC5 code has 14 bits, but we've experimentally determined
131 	 * the meaning for only 11 bits.
132 	 * So, the code translation is not complete. Yet, it is enough to
133 	 * work with the provided RC5 IR.
134 	 */
135 	*protocol = RC_PROTO_RC5;
136 	*scancode = (bitrev8(buf[1]) & 0x1f) << 8 | bitrev8(buf[0]) >> 2;
137 	return 1;
138 }
139 
140 static int em28xx_get_key_pinnacle_usb_grey(struct i2c_client *i2c_dev,
141 					    enum rc_proto *protocol,
142 					    u32 *scancode)
143 {
144 	unsigned char buf[3];
145 
146 	/* poll IR chip */
147 
148 	if (3 != i2c_master_recv(i2c_dev, buf, 3))
149 		return -EIO;
150 
151 	if (buf[0] != 0x00)
152 		return 0;
153 
154 	*protocol = RC_PROTO_UNKNOWN;
155 	*scancode = buf[2] & 0x3f;
156 	return 1;
157 }
158 
159 static int em28xx_get_key_winfast_usbii_deluxe(struct i2c_client *i2c_dev,
160 					       enum rc_proto *protocol,
161 					       u32 *scancode)
162 {
163 	unsigned char subaddr, keydetect, key;
164 
165 	struct i2c_msg msg[] = { { .addr = i2c_dev->addr, .flags = 0, .buf = &subaddr, .len = 1},
166 				 { .addr = i2c_dev->addr, .flags = I2C_M_RD, .buf = &keydetect, .len = 1} };
167 
168 	subaddr = 0x10;
169 	if (2 != i2c_transfer(i2c_dev->adapter, msg, 2))
170 		return -EIO;
171 	if (keydetect == 0x00)
172 		return 0;
173 
174 	subaddr = 0x00;
175 	msg[1].buf = &key;
176 	if (2 != i2c_transfer(i2c_dev->adapter, msg, 2))
177 		return -EIO;
178 	if (key == 0x00)
179 		return 0;
180 
181 	*protocol = RC_PROTO_UNKNOWN;
182 	*scancode = key;
183 	return 1;
184 }
185 
186 /**********************************************************
187  Poll based get keycode functions
188  **********************************************************/
189 
190 /* This is for the em2860/em2880 */
191 static int default_polling_getkey(struct em28xx_IR *ir,
192 				  struct em28xx_ir_poll_result *poll_result)
193 {
194 	struct em28xx *dev = ir->dev;
195 	int rc;
196 	u8 msg[3] = { 0, 0, 0 };
197 
198 	/* Read key toggle, brand, and key code
199 	   on registers 0x45, 0x46 and 0x47
200 	 */
201 	rc = dev->em28xx_read_reg_req_len(dev, 0, EM28XX_R45_IR,
202 					  msg, sizeof(msg));
203 	if (rc < 0)
204 		return rc;
205 
206 	/* Infrared toggle (Reg 0x45[7]) */
207 	poll_result->toggle_bit = (msg[0] >> 7);
208 
209 	/* Infrared read count (Reg 0x45[6:0] */
210 	poll_result->read_count = (msg[0] & 0x7f);
211 
212 	/* Remote Control Address/Data (Regs 0x46/0x47) */
213 	switch (ir->rc_proto) {
214 	case RC_PROTO_BIT_RC5:
215 		poll_result->protocol = RC_PROTO_RC5;
216 		poll_result->scancode = RC_SCANCODE_RC5(msg[1], msg[2]);
217 		break;
218 
219 	case RC_PROTO_BIT_NEC:
220 		poll_result->protocol = RC_PROTO_NEC;
221 		poll_result->scancode = RC_SCANCODE_NEC(msg[1], msg[2]);
222 		break;
223 
224 	default:
225 		poll_result->protocol = RC_PROTO_UNKNOWN;
226 		poll_result->scancode = msg[1] << 8 | msg[2];
227 		break;
228 	}
229 
230 	return 0;
231 }
232 
233 static int em2874_polling_getkey(struct em28xx_IR *ir,
234 				 struct em28xx_ir_poll_result *poll_result)
235 {
236 	struct em28xx *dev = ir->dev;
237 	int rc;
238 	u8 msg[5] = { 0, 0, 0, 0, 0 };
239 
240 	/* Read key toggle, brand, and key code
241 	   on registers 0x51-55
242 	 */
243 	rc = dev->em28xx_read_reg_req_len(dev, 0, EM2874_R51_IR,
244 					  msg, sizeof(msg));
245 	if (rc < 0)
246 		return rc;
247 
248 	/* Infrared toggle (Reg 0x51[7]) */
249 	poll_result->toggle_bit = (msg[0] >> 7);
250 
251 	/* Infrared read count (Reg 0x51[6:0] */
252 	poll_result->read_count = (msg[0] & 0x7f);
253 
254 	/*
255 	 * Remote Control Address (Reg 0x52)
256 	 * Remote Control Data (Reg 0x53-0x55)
257 	 */
258 	switch (ir->rc_proto) {
259 	case RC_PROTO_BIT_RC5:
260 		poll_result->protocol = RC_PROTO_RC5;
261 		poll_result->scancode = RC_SCANCODE_RC5(msg[1], msg[2]);
262 		break;
263 
264 	case RC_PROTO_BIT_NEC:
265 		poll_result->scancode = msg[1] << 8 | msg[2];
266 		if ((msg[3] ^ msg[4]) != 0xff) {	/* 32 bits NEC */
267 			poll_result->protocol = RC_PROTO_NEC32;
268 			poll_result->scancode = RC_SCANCODE_NEC32((msg[1] << 24) |
269 								  (msg[2] << 16) |
270 								  (msg[3] << 8)  |
271 								  (msg[4]));
272 		} else if ((msg[1] ^ msg[2]) != 0xff) {	/* 24 bits NEC */
273 			poll_result->protocol = RC_PROTO_NECX;
274 			poll_result->scancode = RC_SCANCODE_NECX(msg[1] << 8 |
275 								 msg[2], msg[3]);
276 		} else {				/* Normal NEC */
277 			poll_result->protocol = RC_PROTO_NEC;
278 			poll_result->scancode = RC_SCANCODE_NEC(msg[1], msg[3]);
279 		}
280 		break;
281 
282 	case RC_PROTO_BIT_RC6_0:
283 		poll_result->protocol = RC_PROTO_RC6_0;
284 		poll_result->scancode = RC_SCANCODE_RC6_0(msg[1], msg[2]);
285 		break;
286 
287 	default:
288 		poll_result->protocol = RC_PROTO_UNKNOWN;
289 		poll_result->scancode = (msg[1] << 24) | (msg[2] << 16) |
290 					(msg[3] << 8)  | msg[4];
291 		break;
292 	}
293 
294 	return 0;
295 }
296 
297 /**********************************************************
298  Polling code for em28xx
299  **********************************************************/
300 
301 static int em28xx_i2c_ir_handle_key(struct em28xx_IR *ir)
302 {
303 	static u32 scancode;
304 	enum rc_proto protocol;
305 	int rc;
306 
307 	rc = ir->get_key_i2c(ir->i2c_client, &protocol, &scancode);
308 	if (rc < 0) {
309 		dprintk("ir->get_key_i2c() failed: %d\n", rc);
310 		return rc;
311 	}
312 
313 	if (rc) {
314 		dprintk("%s: proto = 0x%04x, scancode = 0x%04x\n",
315 			__func__, protocol, scancode);
316 		rc_keydown(ir->rc, protocol, scancode, 0);
317 	}
318 	return 0;
319 }
320 
321 static void em28xx_ir_handle_key(struct em28xx_IR *ir)
322 {
323 	int result;
324 	struct em28xx_ir_poll_result poll_result;
325 
326 	/* read the registers containing the IR status */
327 	result = ir->get_key(ir, &poll_result);
328 	if (unlikely(result < 0)) {
329 		dprintk("ir->get_key() failed: %d\n", result);
330 		return;
331 	}
332 
333 	if (unlikely(poll_result.read_count != ir->last_readcount)) {
334 		dprintk("%s: toggle: %d, count: %d, key 0x%04x\n", __func__,
335 			poll_result.toggle_bit, poll_result.read_count,
336 			poll_result.scancode);
337 		if (ir->full_code)
338 			rc_keydown(ir->rc,
339 				   poll_result.protocol,
340 				   poll_result.scancode,
341 				   poll_result.toggle_bit);
342 		else
343 			rc_keydown(ir->rc,
344 				   RC_PROTO_UNKNOWN,
345 				   poll_result.scancode & 0xff,
346 				   poll_result.toggle_bit);
347 
348 		if (ir->dev->chip_id == CHIP_ID_EM2874 ||
349 		    ir->dev->chip_id == CHIP_ID_EM2884)
350 			/* The em2874 clears the readcount field every time the
351 			   register is read.  The em2860/2880 datasheet says that it
352 			   is supposed to clear the readcount, but it doesn't.  So with
353 			   the em2874, we are looking for a non-zero read count as
354 			   opposed to a readcount that is incrementing */
355 			ir->last_readcount = 0;
356 		else
357 			ir->last_readcount = poll_result.read_count;
358 	}
359 }
360 
361 static void em28xx_ir_work(struct work_struct *work)
362 {
363 	struct em28xx_IR *ir = container_of(work, struct em28xx_IR, work.work);
364 
365 	if (ir->i2c_client) /* external i2c device */
366 		em28xx_i2c_ir_handle_key(ir);
367 	else /* internal device */
368 		em28xx_ir_handle_key(ir);
369 	schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
370 }
371 
372 static int em28xx_ir_start(struct rc_dev *rc)
373 {
374 	struct em28xx_IR *ir = rc->priv;
375 
376 	INIT_DELAYED_WORK(&ir->work, em28xx_ir_work);
377 	schedule_delayed_work(&ir->work, 0);
378 
379 	return 0;
380 }
381 
382 static void em28xx_ir_stop(struct rc_dev *rc)
383 {
384 	struct em28xx_IR *ir = rc->priv;
385 
386 	cancel_delayed_work_sync(&ir->work);
387 }
388 
389 static int em2860_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_proto)
390 {
391 	struct em28xx_IR *ir = rc_dev->priv;
392 	struct em28xx *dev = ir->dev;
393 
394 	/* Adjust xclk based on IR table for RC5/NEC tables */
395 	if (*rc_proto & RC_PROTO_BIT_RC5) {
396 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
397 		ir->full_code = 1;
398 		*rc_proto = RC_PROTO_BIT_RC5;
399 	} else if (*rc_proto & RC_PROTO_BIT_NEC) {
400 		dev->board.xclk &= ~EM28XX_XCLK_IR_RC5_MODE;
401 		ir->full_code = 1;
402 		*rc_proto = RC_PROTO_BIT_NEC;
403 	} else if (*rc_proto & RC_PROTO_BIT_UNKNOWN) {
404 		*rc_proto = RC_PROTO_BIT_UNKNOWN;
405 	} else {
406 		*rc_proto = ir->rc_proto;
407 		return -EINVAL;
408 	}
409 	em28xx_write_reg_bits(dev, EM28XX_R0F_XCLK, dev->board.xclk,
410 			      EM28XX_XCLK_IR_RC5_MODE);
411 
412 	ir->rc_proto = *rc_proto;
413 
414 	return 0;
415 }
416 
417 static int em2874_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_proto)
418 {
419 	struct em28xx_IR *ir = rc_dev->priv;
420 	struct em28xx *dev = ir->dev;
421 	u8 ir_config = EM2874_IR_RC5;
422 
423 	/* Adjust xclk and set type based on IR table for RC5/NEC/RC6 tables */
424 	if (*rc_proto & RC_PROTO_BIT_RC5) {
425 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
426 		ir->full_code = 1;
427 		*rc_proto = RC_PROTO_BIT_RC5;
428 	} else if (*rc_proto & RC_PROTO_BIT_NEC) {
429 		dev->board.xclk &= ~EM28XX_XCLK_IR_RC5_MODE;
430 		ir_config = EM2874_IR_NEC | EM2874_IR_NEC_NO_PARITY;
431 		ir->full_code = 1;
432 		*rc_proto = RC_PROTO_BIT_NEC;
433 	} else if (*rc_proto & RC_PROTO_BIT_RC6_0) {
434 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
435 		ir_config = EM2874_IR_RC6_MODE_0;
436 		ir->full_code = 1;
437 		*rc_proto = RC_PROTO_BIT_RC6_0;
438 	} else if (*rc_proto & RC_PROTO_BIT_UNKNOWN) {
439 		*rc_proto = RC_PROTO_BIT_UNKNOWN;
440 	} else {
441 		*rc_proto = ir->rc_proto;
442 		return -EINVAL;
443 	}
444 	em28xx_write_regs(dev, EM2874_R50_IR_CONFIG, &ir_config, 1);
445 	em28xx_write_reg_bits(dev, EM28XX_R0F_XCLK, dev->board.xclk,
446 			      EM28XX_XCLK_IR_RC5_MODE);
447 
448 	ir->rc_proto = *rc_proto;
449 
450 	return 0;
451 }
452 
453 static int em28xx_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_proto)
454 {
455 	struct em28xx_IR *ir = rc_dev->priv;
456 	struct em28xx *dev = ir->dev;
457 
458 	/* Setup the proper handler based on the chip */
459 	switch (dev->chip_id) {
460 	case CHIP_ID_EM2860:
461 	case CHIP_ID_EM2883:
462 		return em2860_ir_change_protocol(rc_dev, rc_proto);
463 	case CHIP_ID_EM2884:
464 	case CHIP_ID_EM2874:
465 	case CHIP_ID_EM28174:
466 	case CHIP_ID_EM28178:
467 		return em2874_ir_change_protocol(rc_dev, rc_proto);
468 	default:
469 		dev_err(&ir->dev->intf->dev,
470 			"Unrecognized em28xx chip id 0x%02x: IR not supported\n",
471 			dev->chip_id);
472 		return -EINVAL;
473 	}
474 }
475 
476 static int em28xx_probe_i2c_ir(struct em28xx *dev)
477 {
478 	int i = 0;
479 	/* Leadtek winfast tv USBII deluxe can find a non working IR-device */
480 	/* at address 0x18, so if that address is needed for another board in */
481 	/* the future, please put it after 0x1f. */
482 	const unsigned short addr_list[] = {
483 		 0x1f, 0x30, 0x47, I2C_CLIENT_END
484 	};
485 
486 	while (addr_list[i] != I2C_CLIENT_END) {
487 		if (i2c_probe_func_quick_read(&dev->i2c_adap[dev->def_i2c_bus], addr_list[i]) == 1)
488 			return addr_list[i];
489 		i++;
490 	}
491 
492 	return -ENODEV;
493 }
494 
495 /**********************************************************
496  Handle buttons
497  **********************************************************/
498 
499 static void em28xx_query_buttons(struct work_struct *work)
500 {
501 	struct em28xx *dev =
502 		container_of(work, struct em28xx, buttons_query_work.work);
503 	u8 i, j;
504 	int regval;
505 	bool is_pressed, was_pressed;
506 	const struct em28xx_led *led;
507 
508 	/* Poll and evaluate all addresses */
509 	for (i = 0; i < dev->num_button_polling_addresses; i++) {
510 		/* Read value from register */
511 		regval = em28xx_read_reg(dev, dev->button_polling_addresses[i]);
512 		if (regval < 0)
513 			continue;
514 		/* Check states of the buttons and act */
515 		j = 0;
516 		while (dev->board.buttons[j].role >= 0 &&
517 		       dev->board.buttons[j].role < EM28XX_NUM_BUTTON_ROLES) {
518 			struct em28xx_button *button = &dev->board.buttons[j];
519 			/* Check if button uses the current address */
520 			if (button->reg_r != dev->button_polling_addresses[i]) {
521 				j++;
522 				continue;
523 			}
524 			/* Determine if button is and was pressed last time */
525 			is_pressed = regval & button->mask;
526 			was_pressed = dev->button_polling_last_values[i]
527 				       & button->mask;
528 			if (button->inverted) {
529 				is_pressed = !is_pressed;
530 				was_pressed = !was_pressed;
531 			}
532 			/* Clear button state (if needed) */
533 			if (is_pressed && button->reg_clearing)
534 				em28xx_write_reg(dev, button->reg_clearing,
535 						 (~regval & button->mask)
536 						    | (regval & ~button->mask));
537 			/* Handle button state */
538 			if (!is_pressed || was_pressed) {
539 				j++;
540 				continue;
541 			}
542 			switch (button->role) {
543 			case EM28XX_BUTTON_SNAPSHOT:
544 				/* Emulate the keypress */
545 				input_report_key(dev->sbutton_input_dev,
546 						 EM28XX_SNAPSHOT_KEY, 1);
547 				/* Unpress the key */
548 				input_report_key(dev->sbutton_input_dev,
549 						 EM28XX_SNAPSHOT_KEY, 0);
550 				break;
551 			case EM28XX_BUTTON_ILLUMINATION:
552 				led = em28xx_find_led(dev,
553 						      EM28XX_LED_ILLUMINATION);
554 				/* Switch illumination LED on/off */
555 				if (led)
556 					em28xx_toggle_reg_bits(dev,
557 							       led->gpio_reg,
558 							       led->gpio_mask);
559 				break;
560 			default:
561 				WARN_ONCE(1, "BUG: unhandled button role.");
562 			}
563 			/* Next button */
564 			j++;
565 		}
566 		/* Save current value for comparison during the next polling */
567 		dev->button_polling_last_values[i] = regval;
568 	}
569 	/* Schedule next poll */
570 	schedule_delayed_work(&dev->buttons_query_work,
571 			      msecs_to_jiffies(dev->button_polling_interval));
572 }
573 
574 static int em28xx_register_snapshot_button(struct em28xx *dev)
575 {
576 	struct usb_device *udev = interface_to_usbdev(dev->intf);
577 	struct input_dev *input_dev;
578 	int err;
579 
580 	dev_info(&dev->intf->dev, "Registering snapshot button...\n");
581 	input_dev = input_allocate_device();
582 	if (!input_dev)
583 		return -ENOMEM;
584 
585 	usb_make_path(udev, dev->snapshot_button_path,
586 		      sizeof(dev->snapshot_button_path));
587 	strlcat(dev->snapshot_button_path, "/sbutton",
588 		sizeof(dev->snapshot_button_path));
589 
590 	input_dev->name = "em28xx snapshot button";
591 	input_dev->phys = dev->snapshot_button_path;
592 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
593 	set_bit(EM28XX_SNAPSHOT_KEY, input_dev->keybit);
594 	input_dev->keycodesize = 0;
595 	input_dev->keycodemax = 0;
596 	input_dev->id.bustype = BUS_USB;
597 	input_dev->id.vendor = le16_to_cpu(udev->descriptor.idVendor);
598 	input_dev->id.product = le16_to_cpu(udev->descriptor.idProduct);
599 	input_dev->id.version = 1;
600 	input_dev->dev.parent = &dev->intf->dev;
601 
602 	err = input_register_device(input_dev);
603 	if (err) {
604 		dev_err(&dev->intf->dev, "input_register_device failed\n");
605 		input_free_device(input_dev);
606 		return err;
607 	}
608 
609 	dev->sbutton_input_dev = input_dev;
610 	return 0;
611 }
612 
613 static void em28xx_init_buttons(struct em28xx *dev)
614 {
615 	u8  i = 0, j = 0;
616 	bool addr_new = false;
617 
618 	dev->button_polling_interval = EM28XX_BUTTONS_DEBOUNCED_QUERY_INTERVAL;
619 	while (dev->board.buttons[i].role >= 0 &&
620 	       dev->board.buttons[i].role < EM28XX_NUM_BUTTON_ROLES) {
621 		struct em28xx_button *button = &dev->board.buttons[i];
622 		/* Check if polling address is already on the list */
623 		addr_new = true;
624 		for (j = 0; j < dev->num_button_polling_addresses; j++) {
625 			if (button->reg_r == dev->button_polling_addresses[j]) {
626 				addr_new = false;
627 				break;
628 			}
629 		}
630 		/* Check if max. number of polling addresses is exceeded */
631 		if (addr_new && dev->num_button_polling_addresses
632 					   >= EM28XX_NUM_BUTTON_ADDRESSES_MAX) {
633 			WARN_ONCE(1, "BUG: maximum number of button polling addresses exceeded.");
634 			goto next_button;
635 		}
636 		/* Button role specific checks and actions */
637 		if (button->role == EM28XX_BUTTON_SNAPSHOT) {
638 			/* Register input device */
639 			if (em28xx_register_snapshot_button(dev) < 0)
640 				goto next_button;
641 		} else if (button->role == EM28XX_BUTTON_ILLUMINATION) {
642 			/* Check sanity */
643 			if (!em28xx_find_led(dev, EM28XX_LED_ILLUMINATION)) {
644 				dev_err(&dev->intf->dev,
645 					"BUG: illumination button defined, but no illumination LED.\n");
646 				goto next_button;
647 			}
648 		}
649 		/* Add read address to list of polling addresses */
650 		if (addr_new) {
651 			unsigned int index = dev->num_button_polling_addresses;
652 			dev->button_polling_addresses[index] = button->reg_r;
653 			dev->num_button_polling_addresses++;
654 		}
655 		/* Reduce polling interval if necessary */
656 		if (!button->reg_clearing)
657 			dev->button_polling_interval =
658 					 EM28XX_BUTTONS_VOLATILE_QUERY_INTERVAL;
659 next_button:
660 		/* Next button */
661 		i++;
662 	}
663 
664 	/* Start polling */
665 	if (dev->num_button_polling_addresses) {
666 		memset(dev->button_polling_last_values, 0,
667 		       EM28XX_NUM_BUTTON_ADDRESSES_MAX);
668 		schedule_delayed_work(&dev->buttons_query_work,
669 				      msecs_to_jiffies(dev->button_polling_interval));
670 	}
671 }
672 
673 static void em28xx_shutdown_buttons(struct em28xx *dev)
674 {
675 	/* Cancel polling */
676 	cancel_delayed_work_sync(&dev->buttons_query_work);
677 	/* Clear polling addresses list */
678 	dev->num_button_polling_addresses = 0;
679 	/* Deregister input devices */
680 	if (dev->sbutton_input_dev != NULL) {
681 		dev_info(&dev->intf->dev, "Deregistering snapshot button\n");
682 		input_unregister_device(dev->sbutton_input_dev);
683 		dev->sbutton_input_dev = NULL;
684 	}
685 }
686 
687 static int em28xx_ir_init(struct em28xx *dev)
688 {
689 	struct usb_device *udev = interface_to_usbdev(dev->intf);
690 	struct em28xx_IR *ir;
691 	struct rc_dev *rc;
692 	int err = -ENOMEM;
693 	u64 rc_proto;
694 	u16 i2c_rc_dev_addr = 0;
695 
696 	if (dev->is_audio_only) {
697 		/* Shouldn't initialize IR for this interface */
698 		return 0;
699 	}
700 
701 	kref_get(&dev->ref);
702 	INIT_DELAYED_WORK(&dev->buttons_query_work, em28xx_query_buttons);
703 
704 	if (dev->board.buttons)
705 		em28xx_init_buttons(dev);
706 
707 	if (dev->board.has_ir_i2c) {
708 		i2c_rc_dev_addr = em28xx_probe_i2c_ir(dev);
709 		if (!i2c_rc_dev_addr) {
710 			dev->board.has_ir_i2c = 0;
711 			dev_warn(&dev->intf->dev,
712 				 "No i2c IR remote control device found.\n");
713 			return -ENODEV;
714 		}
715 	}
716 
717 	if (dev->board.ir_codes == NULL && !dev->board.has_ir_i2c) {
718 		/* No remote control support */
719 		dev_warn(&dev->intf->dev,
720 			 "Remote control support is not available for this card.\n");
721 		return 0;
722 	}
723 
724 	dev_info(&dev->intf->dev, "Registering input extension\n");
725 
726 	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
727 	if (!ir)
728 		return -ENOMEM;
729 	rc = rc_allocate_device(RC_DRIVER_SCANCODE);
730 	if (!rc)
731 		goto error;
732 
733 	/* record handles to ourself */
734 	ir->dev = dev;
735 	dev->ir = ir;
736 	ir->rc = rc;
737 
738 	rc->priv = ir;
739 	rc->open = em28xx_ir_start;
740 	rc->close = em28xx_ir_stop;
741 
742 	if (dev->board.has_ir_i2c) {	/* external i2c device */
743 		switch (dev->model) {
744 		case EM2800_BOARD_TERRATEC_CINERGY_200:
745 		case EM2820_BOARD_TERRATEC_CINERGY_250:
746 			rc->map_name = RC_MAP_EM_TERRATEC;
747 			ir->get_key_i2c = em28xx_get_key_terratec;
748 			break;
749 		case EM2820_BOARD_PINNACLE_USB_2:
750 			rc->map_name = RC_MAP_PINNACLE_GREY;
751 			ir->get_key_i2c = em28xx_get_key_pinnacle_usb_grey;
752 			break;
753 		case EM2820_BOARD_HAUPPAUGE_WINTV_USB_2:
754 			rc->map_name = RC_MAP_HAUPPAUGE;
755 			ir->get_key_i2c = em28xx_get_key_em_haup;
756 			rc->allowed_protocols = RC_PROTO_BIT_RC5;
757 			break;
758 		case EM2820_BOARD_LEADTEK_WINFAST_USBII_DELUXE:
759 			rc->map_name = RC_MAP_WINFAST_USBII_DELUXE;
760 			ir->get_key_i2c = em28xx_get_key_winfast_usbii_deluxe;
761 			break;
762 		default:
763 			err = -ENODEV;
764 			goto error;
765 		}
766 
767 		ir->i2c_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
768 		if (!ir->i2c_client)
769 			goto error;
770 		ir->i2c_client->adapter = &ir->dev->i2c_adap[dev->def_i2c_bus];
771 		ir->i2c_client->addr = i2c_rc_dev_addr;
772 		ir->i2c_client->flags = 0;
773 		/* NOTE: all other fields of i2c_client are unused */
774 	} else {	/* internal device */
775 		switch (dev->chip_id) {
776 		case CHIP_ID_EM2860:
777 		case CHIP_ID_EM2883:
778 			rc->allowed_protocols = RC_PROTO_BIT_RC5 |
779 						RC_PROTO_BIT_NEC;
780 			ir->get_key = default_polling_getkey;
781 			break;
782 		case CHIP_ID_EM2884:
783 		case CHIP_ID_EM2874:
784 		case CHIP_ID_EM28174:
785 		case CHIP_ID_EM28178:
786 			ir->get_key = em2874_polling_getkey;
787 			rc->allowed_protocols = RC_PROTO_BIT_RC5 |
788 				RC_PROTO_BIT_NEC | RC_PROTO_BIT_NECX |
789 				RC_PROTO_BIT_NEC32 | RC_PROTO_BIT_RC6_0;
790 			break;
791 		default:
792 			err = -ENODEV;
793 			goto error;
794 		}
795 
796 		rc->change_protocol = em28xx_ir_change_protocol;
797 		rc->map_name = dev->board.ir_codes;
798 
799 		/* By default, keep protocol field untouched */
800 		rc_proto = RC_PROTO_BIT_UNKNOWN;
801 		err = em28xx_ir_change_protocol(rc, &rc_proto);
802 		if (err)
803 			goto error;
804 	}
805 
806 	/* This is how often we ask the chip for IR information */
807 	ir->polling = 100; /* ms */
808 
809 	/* init input device */
810 	snprintf(ir->name, sizeof(ir->name), "%s IR",
811 		 dev_name(&dev->intf->dev));
812 
813 	usb_make_path(udev, ir->phys, sizeof(ir->phys));
814 	strlcat(ir->phys, "/input0", sizeof(ir->phys));
815 
816 	rc->device_name = ir->name;
817 	rc->input_phys = ir->phys;
818 	rc->input_id.bustype = BUS_USB;
819 	rc->input_id.version = 1;
820 	rc->input_id.vendor = le16_to_cpu(udev->descriptor.idVendor);
821 	rc->input_id.product = le16_to_cpu(udev->descriptor.idProduct);
822 	rc->dev.parent = &dev->intf->dev;
823 	rc->driver_name = MODULE_NAME;
824 
825 	/* all done */
826 	err = rc_register_device(rc);
827 	if (err)
828 		goto error;
829 
830 	dev_info(&dev->intf->dev, "Input extension successfully initialized\n");
831 
832 	return 0;
833 
834 error:
835 	kfree(ir->i2c_client);
836 	dev->ir = NULL;
837 	rc_free_device(rc);
838 	kfree(ir);
839 	return err;
840 }
841 
842 static int em28xx_ir_fini(struct em28xx *dev)
843 {
844 	struct em28xx_IR *ir = dev->ir;
845 
846 	if (dev->is_audio_only) {
847 		/* Shouldn't initialize IR for this interface */
848 		return 0;
849 	}
850 
851 	dev_info(&dev->intf->dev, "Closing input extension\n");
852 
853 	em28xx_shutdown_buttons(dev);
854 
855 	/* skip detach on non attached boards */
856 	if (!ir)
857 		goto ref_put;
858 
859 	rc_unregister_device(ir->rc);
860 
861 	kfree(ir->i2c_client);
862 
863 	/* done */
864 	kfree(ir);
865 	dev->ir = NULL;
866 
867 ref_put:
868 	kref_put(&dev->ref, em28xx_free_device);
869 
870 	return 0;
871 }
872 
873 static int em28xx_ir_suspend(struct em28xx *dev)
874 {
875 	struct em28xx_IR *ir = dev->ir;
876 
877 	if (dev->is_audio_only)
878 		return 0;
879 
880 	dev_info(&dev->intf->dev, "Suspending input extension\n");
881 	if (ir)
882 		cancel_delayed_work_sync(&ir->work);
883 	cancel_delayed_work_sync(&dev->buttons_query_work);
884 	/* is canceling delayed work sufficient or does the rc event
885 	   kthread needs stopping? kthread is stopped in
886 	   ir_raw_event_unregister() */
887 	return 0;
888 }
889 
890 static int em28xx_ir_resume(struct em28xx *dev)
891 {
892 	struct em28xx_IR *ir = dev->ir;
893 
894 	if (dev->is_audio_only)
895 		return 0;
896 
897 	dev_info(&dev->intf->dev, "Resuming input extension\n");
898 	/* if suspend calls ir_raw_event_unregister(), the should call
899 	   ir_raw_event_register() */
900 	if (ir)
901 		schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
902 	if (dev->num_button_polling_addresses)
903 		schedule_delayed_work(&dev->buttons_query_work,
904 				      msecs_to_jiffies(dev->button_polling_interval));
905 	return 0;
906 }
907 
908 static struct em28xx_ops rc_ops = {
909 	.id   = EM28XX_RC,
910 	.name = "Em28xx Input Extension",
911 	.init = em28xx_ir_init,
912 	.fini = em28xx_ir_fini,
913 	.suspend = em28xx_ir_suspend,
914 	.resume = em28xx_ir_resume,
915 };
916 
917 static int __init em28xx_rc_register(void)
918 {
919 	return em28xx_register_extension(&rc_ops);
920 }
921 
922 static void __exit em28xx_rc_unregister(void)
923 {
924 	em28xx_unregister_extension(&rc_ops);
925 }
926 
927 MODULE_LICENSE("GPL");
928 MODULE_AUTHOR("Mauro Carvalho Chehab");
929 MODULE_DESCRIPTION(DRIVER_DESC " - input interface");
930 MODULE_VERSION(EM28XX_VERSION);
931 
932 module_init(em28xx_rc_register);
933 module_exit(em28xx_rc_unregister);
934