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 <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/interrupt.h>
28 #include <linux/usb.h>
29 #include <linux/slab.h>
30 #include <linux/bitrev.h>
31 
32 #include "em28xx.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...) \
45 	if (ir_debug) { \
46 		printk(KERN_DEBUG "%s/ir: " fmt, ir->name , ## arg); \
47 	}
48 
49 /**********************************************************
50  Polling structure used by em28xx IR's
51  **********************************************************/
52 
53 struct em28xx_ir_poll_result {
54 	unsigned int toggle_bit:1;
55 	unsigned int read_count:7;
56 
57 	enum rc_type protocol;
58 	u32 scancode;
59 };
60 
61 struct em28xx_IR {
62 	struct em28xx *dev;
63 	struct rc_dev *rc;
64 	char name[32];
65 	char phys[32];
66 
67 	/* poll decoder */
68 	int polling;
69 	struct delayed_work work;
70 	unsigned int full_code:1;
71 	unsigned int last_readcount;
72 	u64 rc_type;
73 
74 	/* i2c slave address of external device (if used) */
75 	u16 i2c_dev_addr;
76 
77 	int  (*get_key_i2c)(struct i2c_client *ir, enum rc_type *protocol, u32 *scancode);
78 	int  (*get_key)(struct em28xx_IR *, struct em28xx_ir_poll_result *);
79 };
80 
81 /**********************************************************
82  I2C IR based get keycodes - should be used with ir-kbd-i2c
83  **********************************************************/
84 
85 static int em28xx_get_key_terratec(struct i2c_client *i2c_dev,
86 				   enum rc_type *protocol, u32 *scancode)
87 {
88 	unsigned char b;
89 
90 	/* poll IR chip */
91 	if (1 != i2c_master_recv(i2c_dev, &b, 1))
92 		return -EIO;
93 
94 	/* it seems that 0xFE indicates that a button is still hold
95 	   down, while 0xff indicates that no button is hold down. */
96 
97 	if (b == 0xff)
98 		return 0;
99 
100 	if (b == 0xfe)
101 		/* keep old data */
102 		return 1;
103 
104 	*protocol = RC_TYPE_UNKNOWN;
105 	*scancode = b;
106 	return 1;
107 }
108 
109 static int em28xx_get_key_em_haup(struct i2c_client *i2c_dev,
110 				  enum rc_type *protocol, u32 *scancode)
111 {
112 	unsigned char buf[2];
113 	int size;
114 
115 	/* poll IR chip */
116 	size = i2c_master_recv(i2c_dev, buf, sizeof(buf));
117 
118 	if (size != 2)
119 		return -EIO;
120 
121 	/* Does eliminate repeated parity code */
122 	if (buf[1] == 0xff)
123 		return 0;
124 
125 	/*
126 	 * Rearranges bits to the right order.
127 	 * The bit order were determined experimentally by using
128 	 * The original Hauppauge Grey IR and another RC5 that uses addr=0x08
129 	 * The RC5 code has 14 bits, but we've experimentally determined
130 	 * the meaning for only 11 bits.
131 	 * So, the code translation is not complete. Yet, it is enough to
132 	 * work with the provided RC5 IR.
133 	 */
134 	*protocol = RC_TYPE_RC5;
135 	*scancode = (bitrev8(buf[1]) & 0x1f) << 8 | bitrev8(buf[0]) >> 2;
136 	return 1;
137 }
138 
139 static int em28xx_get_key_pinnacle_usb_grey(struct i2c_client *i2c_dev,
140 					    enum rc_type *protocol, u32 *scancode)
141 {
142 	unsigned char buf[3];
143 
144 	/* poll IR chip */
145 
146 	if (3 != i2c_master_recv(i2c_dev, buf, 3))
147 		return -EIO;
148 
149 	if (buf[0] != 0x00)
150 		return 0;
151 
152 	*protocol = RC_TYPE_UNKNOWN;
153 	*scancode = buf[2] & 0x3f;
154 	return 1;
155 }
156 
157 static int em28xx_get_key_winfast_usbii_deluxe(struct i2c_client *i2c_dev,
158 					       enum rc_type *protocol, u32 *scancode)
159 {
160 	unsigned char subaddr, keydetect, key;
161 
162 	struct i2c_msg msg[] = { { .addr = i2c_dev->addr, .flags = 0, .buf = &subaddr, .len = 1},
163 				 { .addr = i2c_dev->addr, .flags = I2C_M_RD, .buf = &keydetect, .len = 1} };
164 
165 	subaddr = 0x10;
166 	if (2 != i2c_transfer(i2c_dev->adapter, msg, 2))
167 		return -EIO;
168 	if (keydetect == 0x00)
169 		return 0;
170 
171 	subaddr = 0x00;
172 	msg[1].buf = &key;
173 	if (2 != i2c_transfer(i2c_dev->adapter, msg, 2))
174 		return -EIO;
175 	if (key == 0x00)
176 		return 0;
177 
178 	*protocol = RC_TYPE_UNKNOWN;
179 	*scancode = key;
180 	return 1;
181 }
182 
183 /**********************************************************
184  Poll based get keycode functions
185  **********************************************************/
186 
187 /* This is for the em2860/em2880 */
188 static int default_polling_getkey(struct em28xx_IR *ir,
189 				  struct em28xx_ir_poll_result *poll_result)
190 {
191 	struct em28xx *dev = ir->dev;
192 	int rc;
193 	u8 msg[3] = { 0, 0, 0 };
194 
195 	/* Read key toggle, brand, and key code
196 	   on registers 0x45, 0x46 and 0x47
197 	 */
198 	rc = dev->em28xx_read_reg_req_len(dev, 0, EM28XX_R45_IR,
199 					  msg, sizeof(msg));
200 	if (rc < 0)
201 		return rc;
202 
203 	/* Infrared toggle (Reg 0x45[7]) */
204 	poll_result->toggle_bit = (msg[0] >> 7);
205 
206 	/* Infrared read count (Reg 0x45[6:0] */
207 	poll_result->read_count = (msg[0] & 0x7f);
208 
209 	/* Remote Control Address/Data (Regs 0x46/0x47) */
210 	switch (ir->rc_type) {
211 	case RC_BIT_RC5:
212 		poll_result->protocol = RC_TYPE_RC5;
213 		poll_result->scancode = RC_SCANCODE_RC5(msg[1], msg[2]);
214 		break;
215 
216 	case RC_BIT_NEC:
217 		poll_result->protocol = RC_TYPE_NEC;
218 		poll_result->scancode = RC_SCANCODE_NEC(msg[1], msg[2]);
219 		break;
220 
221 	default:
222 		poll_result->protocol = RC_TYPE_UNKNOWN;
223 		poll_result->scancode = msg[1] << 8 | msg[2];
224 		break;
225 	}
226 
227 	return 0;
228 }
229 
230 static int em2874_polling_getkey(struct em28xx_IR *ir,
231 				 struct em28xx_ir_poll_result *poll_result)
232 {
233 	struct em28xx *dev = ir->dev;
234 	int rc;
235 	u8 msg[5] = { 0, 0, 0, 0, 0 };
236 
237 	/* Read key toggle, brand, and key code
238 	   on registers 0x51-55
239 	 */
240 	rc = dev->em28xx_read_reg_req_len(dev, 0, EM2874_R51_IR,
241 					  msg, sizeof(msg));
242 	if (rc < 0)
243 		return rc;
244 
245 	/* Infrared toggle (Reg 0x51[7]) */
246 	poll_result->toggle_bit = (msg[0] >> 7);
247 
248 	/* Infrared read count (Reg 0x51[6:0] */
249 	poll_result->read_count = (msg[0] & 0x7f);
250 
251 	/*
252 	 * Remote Control Address (Reg 0x52)
253 	 * Remote Control Data (Reg 0x53-0x55)
254 	 */
255 	switch (ir->rc_type) {
256 	case RC_BIT_RC5:
257 		poll_result->protocol = RC_TYPE_RC5;
258 		poll_result->scancode = RC_SCANCODE_RC5(msg[1], msg[2]);
259 		break;
260 
261 	case RC_BIT_NEC:
262 		poll_result->protocol = RC_TYPE_RC5;
263 		poll_result->scancode = msg[1] << 8 | msg[2];
264 		if ((msg[3] ^ msg[4]) != 0xff)		/* 32 bits NEC */
265 			poll_result->scancode = RC_SCANCODE_NEC32((msg[1] << 24) |
266 								  (msg[2] << 16) |
267 								  (msg[3] << 8)  |
268 								  (msg[4]));
269 		else if ((msg[1] ^ msg[2]) != 0xff)	/* 24 bits NEC */
270 			poll_result->scancode = RC_SCANCODE_NECX(msg[1] << 8 |
271 								 msg[2], msg[3]);
272 		else					/* Normal NEC */
273 			poll_result->scancode = RC_SCANCODE_NEC(msg[1], msg[3]);
274 		break;
275 
276 	case RC_BIT_RC6_0:
277 		poll_result->protocol = RC_TYPE_RC6_0;
278 		poll_result->scancode = RC_SCANCODE_RC6_0(msg[1], msg[2]);
279 		break;
280 
281 	default:
282 		poll_result->protocol = RC_TYPE_UNKNOWN;
283 		poll_result->scancode = (msg[1] << 24) | (msg[2] << 16) |
284 					(msg[3] << 8)  | msg[4];
285 		break;
286 	}
287 
288 	return 0;
289 }
290 
291 /**********************************************************
292  Polling code for em28xx
293  **********************************************************/
294 
295 static int em28xx_i2c_ir_handle_key(struct em28xx_IR *ir)
296 {
297 	struct em28xx *dev = ir->dev;
298 	static u32 scancode;
299 	enum rc_type protocol;
300 	int rc;
301 	struct i2c_client client;
302 
303 	client.adapter = &ir->dev->i2c_adap[dev->def_i2c_bus];
304 	client.addr = ir->i2c_dev_addr;
305 
306 	rc = ir->get_key_i2c(&client, &protocol, &scancode);
307 	if (rc < 0) {
308 		dprintk("ir->get_key_i2c() failed: %d\n", rc);
309 		return rc;
310 	}
311 
312 	if (rc) {
313 		dprintk("%s: proto = 0x%04x, scancode = 0x%04x\n",
314 			__func__, protocol, scancode);
315 		rc_keydown(ir->rc, protocol, scancode, 0);
316 	}
317 	return 0;
318 }
319 
320 static void em28xx_ir_handle_key(struct em28xx_IR *ir)
321 {
322 	int result;
323 	struct em28xx_ir_poll_result poll_result;
324 
325 	/* read the registers containing the IR status */
326 	result = ir->get_key(ir, &poll_result);
327 	if (unlikely(result < 0)) {
328 		dprintk("ir->get_key() failed: %d\n", result);
329 		return;
330 	}
331 
332 	if (unlikely(poll_result.read_count != ir->last_readcount)) {
333 		dprintk("%s: toggle: %d, count: %d, key 0x%04x\n", __func__,
334 			poll_result.toggle_bit, poll_result.read_count,
335 			poll_result.scancode);
336 		if (ir->full_code)
337 			rc_keydown(ir->rc,
338 				   poll_result.protocol,
339 				   poll_result.scancode,
340 				   poll_result.toggle_bit);
341 		else
342 			rc_keydown(ir->rc,
343 				   RC_TYPE_UNKNOWN,
344 				   poll_result.scancode & 0xff,
345 				   poll_result.toggle_bit);
346 
347 		if (ir->dev->chip_id == CHIP_ID_EM2874 ||
348 		    ir->dev->chip_id == CHIP_ID_EM2884)
349 			/* The em2874 clears the readcount field every time the
350 			   register is read.  The em2860/2880 datasheet says that it
351 			   is supposed to clear the readcount, but it doesn't.  So with
352 			   the em2874, we are looking for a non-zero read count as
353 			   opposed to a readcount that is incrementing */
354 			ir->last_readcount = 0;
355 		else
356 			ir->last_readcount = poll_result.read_count;
357 	}
358 }
359 
360 static void em28xx_ir_work(struct work_struct *work)
361 {
362 	struct em28xx_IR *ir = container_of(work, struct em28xx_IR, work.work);
363 
364 	if (ir->i2c_dev_addr) /* external i2c device */
365 		em28xx_i2c_ir_handle_key(ir);
366 	else /* internal device */
367 		em28xx_ir_handle_key(ir);
368 	schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
369 }
370 
371 static int em28xx_ir_start(struct rc_dev *rc)
372 {
373 	struct em28xx_IR *ir = rc->priv;
374 
375 	INIT_DELAYED_WORK(&ir->work, em28xx_ir_work);
376 	schedule_delayed_work(&ir->work, 0);
377 
378 	return 0;
379 }
380 
381 static void em28xx_ir_stop(struct rc_dev *rc)
382 {
383 	struct em28xx_IR *ir = rc->priv;
384 
385 	cancel_delayed_work_sync(&ir->work);
386 }
387 
388 static int em2860_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_type)
389 {
390 	struct em28xx_IR *ir = rc_dev->priv;
391 	struct em28xx *dev = ir->dev;
392 
393 	/* Adjust xclk based on IR table for RC5/NEC tables */
394 	if (*rc_type & RC_BIT_RC5) {
395 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
396 		ir->full_code = 1;
397 		*rc_type = RC_BIT_RC5;
398 	} else if (*rc_type & RC_BIT_NEC) {
399 		dev->board.xclk &= ~EM28XX_XCLK_IR_RC5_MODE;
400 		ir->full_code = 1;
401 		*rc_type = RC_BIT_NEC;
402 	} else if (*rc_type & RC_BIT_UNKNOWN) {
403 		*rc_type = RC_BIT_UNKNOWN;
404 	} else {
405 		*rc_type = ir->rc_type;
406 		return -EINVAL;
407 	}
408 	em28xx_write_reg_bits(dev, EM28XX_R0F_XCLK, dev->board.xclk,
409 			      EM28XX_XCLK_IR_RC5_MODE);
410 
411 	ir->rc_type = *rc_type;
412 
413 	return 0;
414 }
415 
416 static int em2874_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_type)
417 {
418 	struct em28xx_IR *ir = rc_dev->priv;
419 	struct em28xx *dev = ir->dev;
420 	u8 ir_config = EM2874_IR_RC5;
421 
422 	/* Adjust xclk and set type based on IR table for RC5/NEC/RC6 tables */
423 	if (*rc_type & RC_BIT_RC5) {
424 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
425 		ir->full_code = 1;
426 		*rc_type = RC_BIT_RC5;
427 	} else if (*rc_type & RC_BIT_NEC) {
428 		dev->board.xclk &= ~EM28XX_XCLK_IR_RC5_MODE;
429 		ir_config = EM2874_IR_NEC | EM2874_IR_NEC_NO_PARITY;
430 		ir->full_code = 1;
431 		*rc_type = RC_BIT_NEC;
432 	} else if (*rc_type & RC_BIT_RC6_0) {
433 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
434 		ir_config = EM2874_IR_RC6_MODE_0;
435 		ir->full_code = 1;
436 		*rc_type = RC_BIT_RC6_0;
437 	} else if (*rc_type & RC_BIT_UNKNOWN) {
438 		*rc_type = RC_BIT_UNKNOWN;
439 	} else {
440 		*rc_type = ir->rc_type;
441 		return -EINVAL;
442 	}
443 	em28xx_write_regs(dev, EM2874_R50_IR_CONFIG, &ir_config, 1);
444 	em28xx_write_reg_bits(dev, EM28XX_R0F_XCLK, dev->board.xclk,
445 			      EM28XX_XCLK_IR_RC5_MODE);
446 
447 	ir->rc_type = *rc_type;
448 
449 	return 0;
450 }
451 static int em28xx_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_type)
452 {
453 	struct em28xx_IR *ir = rc_dev->priv;
454 	struct em28xx *dev = ir->dev;
455 
456 	/* Setup the proper handler based on the chip */
457 	switch (dev->chip_id) {
458 	case CHIP_ID_EM2860:
459 	case CHIP_ID_EM2883:
460 		return em2860_ir_change_protocol(rc_dev, rc_type);
461 	case CHIP_ID_EM2884:
462 	case CHIP_ID_EM2874:
463 	case CHIP_ID_EM28174:
464 	case CHIP_ID_EM28178:
465 		return em2874_ir_change_protocol(rc_dev, rc_type);
466 	default:
467 		printk("Unrecognized em28xx chip id 0x%02x: IR not supported\n",
468 			dev->chip_id);
469 		return -EINVAL;
470 	}
471 }
472 
473 static int em28xx_probe_i2c_ir(struct em28xx *dev)
474 {
475 	int i = 0;
476 	/* Leadtek winfast tv USBII deluxe can find a non working IR-device */
477 	/* at address 0x18, so if that address is needed for another board in */
478 	/* the future, please put it after 0x1f. */
479 	const unsigned short addr_list[] = {
480 		 0x1f, 0x30, 0x47, I2C_CLIENT_END
481 	};
482 
483 	while (addr_list[i] != I2C_CLIENT_END) {
484 		if (i2c_probe_func_quick_read(&dev->i2c_adap[dev->def_i2c_bus], addr_list[i]) == 1)
485 			return addr_list[i];
486 		i++;
487 	}
488 
489 	return -ENODEV;
490 }
491 
492 /**********************************************************
493  Handle buttons
494  **********************************************************/
495 
496 static void em28xx_query_buttons(struct work_struct *work)
497 {
498 	struct em28xx *dev =
499 		container_of(work, struct em28xx, buttons_query_work.work);
500 	u8 i, j;
501 	int regval;
502 	bool is_pressed, was_pressed;
503 	const struct em28xx_led *led;
504 
505 	/* Poll and evaluate all addresses */
506 	for (i = 0; i < dev->num_button_polling_addresses; i++) {
507 		/* Read value from register */
508 		regval = em28xx_read_reg(dev, dev->button_polling_addresses[i]);
509 		if (regval < 0)
510 			continue;
511 		/* Check states of the buttons and act */
512 		j = 0;
513 		while (dev->board.buttons[j].role >= 0 &&
514 			 dev->board.buttons[j].role < EM28XX_NUM_BUTTON_ROLES) {
515 			struct em28xx_button *button = &dev->board.buttons[j];
516 			/* Check if button uses the current address */
517 			if (button->reg_r != dev->button_polling_addresses[i]) {
518 				j++;
519 				continue;
520 			}
521 			/* Determine if button is and was pressed last time */
522 			is_pressed = regval & button->mask;
523 			was_pressed = dev->button_polling_last_values[i]
524 				       & button->mask;
525 			if (button->inverted) {
526 				is_pressed = !is_pressed;
527 				was_pressed = !was_pressed;
528 			}
529 			/* Clear button state (if needed) */
530 			if (is_pressed && button->reg_clearing)
531 				em28xx_write_reg(dev, button->reg_clearing,
532 						 (~regval & button->mask)
533 						    | (regval & ~button->mask));
534 			/* Handle button state */
535 			if (!is_pressed || was_pressed) {
536 				j++;
537 				continue;
538 			}
539 			switch (button->role) {
540 			case EM28XX_BUTTON_SNAPSHOT:
541 				/* Emulate the keypress */
542 				input_report_key(dev->sbutton_input_dev,
543 						 EM28XX_SNAPSHOT_KEY, 1);
544 				/* Unpress the key */
545 				input_report_key(dev->sbutton_input_dev,
546 						 EM28XX_SNAPSHOT_KEY, 0);
547 				break;
548 			case EM28XX_BUTTON_ILLUMINATION:
549 				led = em28xx_find_led(dev,
550 						      EM28XX_LED_ILLUMINATION);
551 				/* Switch illumination LED on/off */
552 				if (led)
553 					em28xx_toggle_reg_bits(dev,
554 							       led->gpio_reg,
555 							       led->gpio_mask);
556 				break;
557 			default:
558 				WARN_ONCE(1, "BUG: unhandled button role.");
559 			}
560 			/* Next button */
561 			j++;
562 		}
563 		/* Save current value for comparison during the next polling */
564 		dev->button_polling_last_values[i] = regval;
565 	}
566 	/* Schedule next poll */
567 	schedule_delayed_work(&dev->buttons_query_work,
568 			      msecs_to_jiffies(dev->button_polling_interval));
569 }
570 
571 static int em28xx_register_snapshot_button(struct em28xx *dev)
572 {
573 	struct input_dev *input_dev;
574 	int err;
575 
576 	em28xx_info("Registering snapshot button...\n");
577 	input_dev = input_allocate_device();
578 	if (!input_dev)
579 		return -ENOMEM;
580 
581 	usb_make_path(dev->udev, dev->snapshot_button_path,
582 		      sizeof(dev->snapshot_button_path));
583 	strlcat(dev->snapshot_button_path, "/sbutton",
584 		sizeof(dev->snapshot_button_path));
585 
586 	input_dev->name = "em28xx snapshot button";
587 	input_dev->phys = dev->snapshot_button_path;
588 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
589 	set_bit(EM28XX_SNAPSHOT_KEY, input_dev->keybit);
590 	input_dev->keycodesize = 0;
591 	input_dev->keycodemax = 0;
592 	input_dev->id.bustype = BUS_USB;
593 	input_dev->id.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
594 	input_dev->id.product = le16_to_cpu(dev->udev->descriptor.idProduct);
595 	input_dev->id.version = 1;
596 	input_dev->dev.parent = &dev->udev->dev;
597 
598 	err = input_register_device(input_dev);
599 	if (err) {
600 		em28xx_errdev("input_register_device failed\n");
601 		input_free_device(input_dev);
602 		return err;
603 	}
604 
605 	dev->sbutton_input_dev = input_dev;
606 	return 0;
607 }
608 
609 static void em28xx_init_buttons(struct em28xx *dev)
610 {
611 	u8  i = 0, j = 0;
612 	bool addr_new = 0;
613 
614 	dev->button_polling_interval = EM28XX_BUTTONS_DEBOUNCED_QUERY_INTERVAL;
615 	while (dev->board.buttons[i].role >= 0 &&
616 			 dev->board.buttons[i].role < EM28XX_NUM_BUTTON_ROLES) {
617 		struct em28xx_button *button = &dev->board.buttons[i];
618 		/* Check if polling address is already on the list */
619 		addr_new = 1;
620 		for (j = 0; j < dev->num_button_polling_addresses; j++) {
621 			if (button->reg_r == dev->button_polling_addresses[j]) {
622 				addr_new = 0;
623 				break;
624 			}
625 		}
626 		/* Check if max. number of polling addresses is exceeded */
627 		if (addr_new && dev->num_button_polling_addresses
628 					   >= EM28XX_NUM_BUTTON_ADDRESSES_MAX) {
629 			WARN_ONCE(1, "BUG: maximum number of button polling addresses exceeded.");
630 			goto next_button;
631 		}
632 		/* Button role specific checks and actions */
633 		if (button->role == EM28XX_BUTTON_SNAPSHOT) {
634 			/* Register input device */
635 			if (em28xx_register_snapshot_button(dev) < 0)
636 				goto next_button;
637 		} else if (button->role == EM28XX_BUTTON_ILLUMINATION) {
638 			/* Check sanity */
639 			if (!em28xx_find_led(dev, EM28XX_LED_ILLUMINATION)) {
640 				em28xx_errdev("BUG: illumination button defined, but no illumination LED.\n");
641 				goto next_button;
642 			}
643 		}
644 		/* Add read address to list of polling addresses */
645 		if (addr_new) {
646 			unsigned int index = dev->num_button_polling_addresses;
647 			dev->button_polling_addresses[index] = button->reg_r;
648 			dev->num_button_polling_addresses++;
649 		}
650 		/* Reduce polling interval if necessary */
651 		if (!button->reg_clearing)
652 			dev->button_polling_interval =
653 					 EM28XX_BUTTONS_VOLATILE_QUERY_INTERVAL;
654 next_button:
655 		/* Next button */
656 		i++;
657 	}
658 
659 	/* Start polling */
660 	if (dev->num_button_polling_addresses) {
661 		memset(dev->button_polling_last_values, 0,
662 					       EM28XX_NUM_BUTTON_ADDRESSES_MAX);
663 		INIT_DELAYED_WORK(&dev->buttons_query_work,
664 							  em28xx_query_buttons);
665 		schedule_delayed_work(&dev->buttons_query_work,
666 			       msecs_to_jiffies(dev->button_polling_interval));
667 	}
668 }
669 
670 static void em28xx_shutdown_buttons(struct em28xx *dev)
671 {
672 	/* Cancel polling */
673 	cancel_delayed_work_sync(&dev->buttons_query_work);
674 	/* Clear polling addresses list */
675 	dev->num_button_polling_addresses = 0;
676 	/* Deregister input devices */
677 	if (dev->sbutton_input_dev != NULL) {
678 		em28xx_info("Deregistering snapshot button\n");
679 		input_unregister_device(dev->sbutton_input_dev);
680 		dev->sbutton_input_dev = NULL;
681 	}
682 }
683 
684 static int em28xx_ir_init(struct em28xx *dev)
685 {
686 	struct em28xx_IR *ir;
687 	struct rc_dev *rc;
688 	int err = -ENOMEM;
689 	u64 rc_type;
690 	u16 i2c_rc_dev_addr = 0;
691 
692 	if (dev->is_audio_only) {
693 		/* Shouldn't initialize IR for this interface */
694 		return 0;
695 	}
696 
697 	kref_get(&dev->ref);
698 
699 	if (dev->board.buttons)
700 		em28xx_init_buttons(dev);
701 
702 	if (dev->board.has_ir_i2c) {
703 		i2c_rc_dev_addr = em28xx_probe_i2c_ir(dev);
704 		if (!i2c_rc_dev_addr) {
705 			dev->board.has_ir_i2c = 0;
706 			em28xx_warn("No i2c IR remote control device found.\n");
707 			return -ENODEV;
708 		}
709 	}
710 
711 	if (dev->board.ir_codes == NULL && !dev->board.has_ir_i2c) {
712 		/* No remote control support */
713 		em28xx_warn("Remote control support is not available for "
714 				"this card.\n");
715 		return 0;
716 	}
717 
718 	em28xx_info("Registering input extension\n");
719 
720 	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
721 	rc = rc_allocate_device();
722 	if (!ir || !rc)
723 		goto error;
724 
725 	/* record handles to ourself */
726 	ir->dev = dev;
727 	dev->ir = ir;
728 	ir->rc = rc;
729 
730 	rc->priv = ir;
731 	rc->open = em28xx_ir_start;
732 	rc->close = em28xx_ir_stop;
733 
734 	if (dev->board.has_ir_i2c) {	/* external i2c device */
735 		switch (dev->model) {
736 		case EM2800_BOARD_TERRATEC_CINERGY_200:
737 		case EM2820_BOARD_TERRATEC_CINERGY_250:
738 			rc->map_name = RC_MAP_EM_TERRATEC;
739 			ir->get_key_i2c = em28xx_get_key_terratec;
740 			break;
741 		case EM2820_BOARD_PINNACLE_USB_2:
742 			rc->map_name = RC_MAP_PINNACLE_GREY;
743 			ir->get_key_i2c = em28xx_get_key_pinnacle_usb_grey;
744 			break;
745 		case EM2820_BOARD_HAUPPAUGE_WINTV_USB_2:
746 			rc->map_name = RC_MAP_HAUPPAUGE;
747 			ir->get_key_i2c = em28xx_get_key_em_haup;
748 			rc->allowed_protocols = RC_BIT_RC5;
749 			break;
750 		case EM2820_BOARD_LEADTEK_WINFAST_USBII_DELUXE:
751 			rc->map_name = RC_MAP_WINFAST_USBII_DELUXE;
752 			ir->get_key_i2c = em28xx_get_key_winfast_usbii_deluxe;
753 			break;
754 		default:
755 			err = -ENODEV;
756 			goto error;
757 		}
758 
759 		ir->i2c_dev_addr = i2c_rc_dev_addr;
760 	} else {	/* internal device */
761 		switch (dev->chip_id) {
762 		case CHIP_ID_EM2860:
763 		case CHIP_ID_EM2883:
764 			rc->allowed_protocols = RC_BIT_RC5 | RC_BIT_NEC;
765 			ir->get_key = default_polling_getkey;
766 			break;
767 		case CHIP_ID_EM2884:
768 		case CHIP_ID_EM2874:
769 		case CHIP_ID_EM28174:
770 		case CHIP_ID_EM28178:
771 			ir->get_key = em2874_polling_getkey;
772 			rc->allowed_protocols = RC_BIT_RC5 | RC_BIT_NEC |
773 					     RC_BIT_RC6_0;
774 			break;
775 		default:
776 			err = -ENODEV;
777 			goto error;
778 		}
779 
780 		rc->change_protocol = em28xx_ir_change_protocol;
781 		rc->map_name = dev->board.ir_codes;
782 
783 		/* By default, keep protocol field untouched */
784 		rc_type = RC_BIT_UNKNOWN;
785 		err = em28xx_ir_change_protocol(rc, &rc_type);
786 		if (err)
787 			goto error;
788 	}
789 
790 	/* This is how often we ask the chip for IR information */
791 	ir->polling = 100; /* ms */
792 
793 	/* init input device */
794 	snprintf(ir->name, sizeof(ir->name), "em28xx IR (%s)", dev->name);
795 
796 	usb_make_path(dev->udev, ir->phys, sizeof(ir->phys));
797 	strlcat(ir->phys, "/input0", sizeof(ir->phys));
798 
799 	rc->input_name = ir->name;
800 	rc->input_phys = ir->phys;
801 	rc->input_id.bustype = BUS_USB;
802 	rc->input_id.version = 1;
803 	rc->input_id.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
804 	rc->input_id.product = le16_to_cpu(dev->udev->descriptor.idProduct);
805 	rc->dev.parent = &dev->udev->dev;
806 	rc->driver_name = MODULE_NAME;
807 
808 	/* all done */
809 	err = rc_register_device(rc);
810 	if (err)
811 		goto error;
812 
813 	em28xx_info("Input extension successfully initalized\n");
814 
815 	return 0;
816 
817 error:
818 	dev->ir = NULL;
819 	rc_free_device(rc);
820 	kfree(ir);
821 	return err;
822 }
823 
824 static int em28xx_ir_fini(struct em28xx *dev)
825 {
826 	struct em28xx_IR *ir = dev->ir;
827 
828 	if (dev->is_audio_only) {
829 		/* Shouldn't initialize IR for this interface */
830 		return 0;
831 	}
832 
833 	em28xx_info("Closing input extension");
834 
835 	em28xx_shutdown_buttons(dev);
836 
837 	/* skip detach on non attached boards */
838 	if (!ir)
839 		goto ref_put;
840 
841 	if (ir->rc)
842 		rc_unregister_device(ir->rc);
843 
844 	/* done */
845 	kfree(ir);
846 	dev->ir = NULL;
847 
848 ref_put:
849 	kref_put(&dev->ref, em28xx_free_device);
850 
851 	return 0;
852 }
853 
854 static int em28xx_ir_suspend(struct em28xx *dev)
855 {
856 	struct em28xx_IR *ir = dev->ir;
857 
858 	if (dev->is_audio_only)
859 		return 0;
860 
861 	em28xx_info("Suspending input extension");
862 	if (ir)
863 		cancel_delayed_work_sync(&ir->work);
864 	cancel_delayed_work_sync(&dev->buttons_query_work);
865 	/* is canceling delayed work sufficient or does the rc event
866 	   kthread needs stopping? kthread is stopped in
867 	   ir_raw_event_unregister() */
868 	return 0;
869 }
870 
871 static int em28xx_ir_resume(struct em28xx *dev)
872 {
873 	struct em28xx_IR *ir = dev->ir;
874 
875 	if (dev->is_audio_only)
876 		return 0;
877 
878 	em28xx_info("Resuming input extension");
879 	/* if suspend calls ir_raw_event_unregister(), the should call
880 	   ir_raw_event_register() */
881 	if (ir)
882 		schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
883 	if (dev->num_button_polling_addresses)
884 		schedule_delayed_work(&dev->buttons_query_work,
885 			       msecs_to_jiffies(dev->button_polling_interval));
886 	return 0;
887 }
888 
889 static struct em28xx_ops rc_ops = {
890 	.id   = EM28XX_RC,
891 	.name = "Em28xx Input Extension",
892 	.init = em28xx_ir_init,
893 	.fini = em28xx_ir_fini,
894 	.suspend = em28xx_ir_suspend,
895 	.resume = em28xx_ir_resume,
896 };
897 
898 static int __init em28xx_rc_register(void)
899 {
900 	return em28xx_register_extension(&rc_ops);
901 }
902 
903 static void __exit em28xx_rc_unregister(void)
904 {
905 	em28xx_unregister_extension(&rc_ops);
906 }
907 
908 MODULE_LICENSE("GPL");
909 MODULE_AUTHOR("Mauro Carvalho Chehab");
910 MODULE_DESCRIPTION(DRIVER_DESC " - input interface");
911 MODULE_VERSION(EM28XX_VERSION);
912 
913 module_init(em28xx_rc_register);
914 module_exit(em28xx_rc_unregister);
915