1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // handle em28xx IR remotes via linux kernel input layer.
4 //
5 // Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it>
6 //		      Markus Rechberger <mrechberger@gmail.com>
7 //		      Mauro Carvalho Chehab <mchehab@kernel.org>
8 //		      Sascha Sommer <saschasommer@freenet.de>
9 //
10 // This program is free software; you can redistribute it and/or modify
11 // it under the terms of the GNU General Public License as published by
12 // the Free Software Foundation; either version 2 of the License, or
13 // (at your option) any later version.
14 //
15 // This program is distributed in the hope that it will be useful,
16 // but WITHOUT ANY WARRANTY; without even the implied warranty of
17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 // GNU General Public License for more details.
19 
20 #include "em28xx.h"
21 
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/delay.h>
25 #include <linux/interrupt.h>
26 #include <linux/usb.h>
27 #include <linux/slab.h>
28 #include <linux/bitrev.h>
29 
30 #define EM28XX_SNAPSHOT_KEY				KEY_CAMERA
31 #define EM28XX_BUTTONS_DEBOUNCED_QUERY_INTERVAL		500 /* [ms] */
32 #define EM28XX_BUTTONS_VOLATILE_QUERY_INTERVAL		100 /* [ms] */
33 
34 static unsigned int ir_debug;
35 module_param(ir_debug, int, 0644);
36 MODULE_PARM_DESC(ir_debug, "enable debug messages [IR]");
37 
38 #define MODULE_NAME "em28xx"
39 
40 #define dprintk(fmt, arg...) do {					\
41 	if (ir_debug)							\
42 		dev_printk(KERN_DEBUG, &ir->dev->intf->dev,		\
43 			   "input: %s: " fmt, __func__, ## arg);	\
44 } while (0)
45 
46 /*
47  * Polling structure used by em28xx IR's
48  */
49 
50 struct em28xx_ir_poll_result {
51 	unsigned int toggle_bit:1;
52 	unsigned int read_count:7;
53 
54 	enum rc_proto protocol;
55 	u32 scancode;
56 };
57 
58 struct em28xx_IR {
59 	struct em28xx *dev;
60 	struct rc_dev *rc;
61 	char name[32];
62 	char phys[32];
63 
64 	/* poll decoder */
65 	int polling;
66 	struct delayed_work work;
67 	unsigned int full_code:1;
68 	unsigned int last_readcount;
69 	u64 rc_proto;
70 
71 	struct i2c_client *i2c_client;
72 
73 	int  (*get_key_i2c)(struct i2c_client *ir, enum rc_proto *protocol,
74 			    u32 *scancode);
75 	int  (*get_key)(struct em28xx_IR *ir, struct em28xx_ir_poll_result *r);
76 };
77 
78 /*
79  * I2C IR based get keycodes - should be used with ir-kbd-i2c
80  */
81 
82 static int em28xx_get_key_terratec(struct i2c_client *i2c_dev,
83 				   enum rc_proto *protocol, u32 *scancode)
84 {
85 	int rc;
86 	unsigned char b;
87 
88 	/* poll IR chip */
89 	rc = i2c_master_recv(i2c_dev, &b, 1);
90 	if (rc != 1) {
91 		if (rc < 0)
92 			return rc;
93 		return -EIO;
94 	}
95 
96 	/*
97 	 * it seems that 0xFE indicates that a button is still hold
98 	 * down, while 0xff indicates that no button is hold down.
99 	 */
100 
101 	if (b == 0xff)
102 		return 0;
103 
104 	if (b == 0xfe)
105 		/* keep old data */
106 		return 1;
107 
108 	*protocol = RC_PROTO_UNKNOWN;
109 	*scancode = b;
110 	return 1;
111 }
112 
113 static int em28xx_get_key_em_haup(struct i2c_client *i2c_dev,
114 				  enum rc_proto *protocol, u32 *scancode)
115 {
116 	unsigned char buf[2];
117 	int size;
118 
119 	/* poll IR chip */
120 	size = i2c_master_recv(i2c_dev, buf, sizeof(buf));
121 
122 	if (size != 2)
123 		return -EIO;
124 
125 	/* Does eliminate repeated parity code */
126 	if (buf[1] == 0xff)
127 		return 0;
128 
129 	/*
130 	 * Rearranges bits to the right order.
131 	 * The bit order were determined experimentally by using
132 	 * The original Hauppauge Grey IR and another RC5 that uses addr=0x08
133 	 * The RC5 code has 14 bits, but we've experimentally determined
134 	 * the meaning for only 11 bits.
135 	 * So, the code translation is not complete. Yet, it is enough to
136 	 * work with the provided RC5 IR.
137 	 */
138 	*protocol = RC_PROTO_RC5;
139 	*scancode = (bitrev8(buf[1]) & 0x1f) << 8 | bitrev8(buf[0]) >> 2;
140 	return 1;
141 }
142 
143 static int em28xx_get_key_pinnacle_usb_grey(struct i2c_client *i2c_dev,
144 					    enum rc_proto *protocol,
145 					    u32 *scancode)
146 {
147 	unsigned char buf[3];
148 
149 	/* poll IR chip */
150 
151 	if (i2c_master_recv(i2c_dev, buf, 3) != 3)
152 		return -EIO;
153 
154 	if (buf[0] != 0x00)
155 		return 0;
156 
157 	*protocol = RC_PROTO_UNKNOWN;
158 	*scancode = buf[2] & 0x3f;
159 	return 1;
160 }
161 
162 static int em28xx_get_key_winfast_usbii_deluxe(struct i2c_client *i2c_dev,
163 					       enum rc_proto *protocol,
164 					       u32 *scancode)
165 {
166 	unsigned char subaddr, keydetect, key;
167 
168 	struct i2c_msg msg[] = {
169 		{
170 			.addr = i2c_dev->addr,
171 			.flags = 0,
172 			.buf = &subaddr, .len = 1
173 		}, {
174 			.addr = i2c_dev->addr,
175 			.flags = I2C_M_RD,
176 			.buf = &keydetect,
177 			.len = 1
178 		}
179 	};
180 
181 	subaddr = 0x10;
182 	if (i2c_transfer(i2c_dev->adapter, msg, 2) != 2)
183 		return -EIO;
184 	if (keydetect == 0x00)
185 		return 0;
186 
187 	subaddr = 0x00;
188 	msg[1].buf = &key;
189 	if (i2c_transfer(i2c_dev->adapter, msg, 2) != 2)
190 		return -EIO;
191 	if (key == 0x00)
192 		return 0;
193 
194 	*protocol = RC_PROTO_UNKNOWN;
195 	*scancode = key;
196 	return 1;
197 }
198 
199 /*
200  * Poll based get keycode functions
201  */
202 
203 /* This is for the em2860/em2880 */
204 static int default_polling_getkey(struct em28xx_IR *ir,
205 				  struct em28xx_ir_poll_result *poll_result)
206 {
207 	struct em28xx *dev = ir->dev;
208 	int rc;
209 	u8 msg[3] = { 0, 0, 0 };
210 
211 	/*
212 	 * Read key toggle, brand, and key code
213 	 * on registers 0x45, 0x46 and 0x47
214 	 */
215 	rc = dev->em28xx_read_reg_req_len(dev, 0, EM28XX_R45_IR,
216 					  msg, sizeof(msg));
217 	if (rc < 0)
218 		return rc;
219 
220 	/* Infrared toggle (Reg 0x45[7]) */
221 	poll_result->toggle_bit = (msg[0] >> 7);
222 
223 	/* Infrared read count (Reg 0x45[6:0] */
224 	poll_result->read_count = (msg[0] & 0x7f);
225 
226 	/* Remote Control Address/Data (Regs 0x46/0x47) */
227 	switch (ir->rc_proto) {
228 	case RC_PROTO_BIT_RC5:
229 		poll_result->protocol = RC_PROTO_RC5;
230 		poll_result->scancode = RC_SCANCODE_RC5(msg[1], msg[2]);
231 		break;
232 
233 	case RC_PROTO_BIT_NEC:
234 		poll_result->protocol = RC_PROTO_NEC;
235 		poll_result->scancode = RC_SCANCODE_NEC(msg[1], msg[2]);
236 		break;
237 
238 	default:
239 		poll_result->protocol = RC_PROTO_UNKNOWN;
240 		poll_result->scancode = msg[1] << 8 | msg[2];
241 		break;
242 	}
243 
244 	return 0;
245 }
246 
247 static int em2874_polling_getkey(struct em28xx_IR *ir,
248 				 struct em28xx_ir_poll_result *poll_result)
249 {
250 	struct em28xx *dev = ir->dev;
251 	int rc;
252 	u8 msg[5] = { 0, 0, 0, 0, 0 };
253 
254 	/*
255 	 * Read key toggle, brand, and key code
256 	 * on registers 0x51-55
257 	 */
258 	rc = dev->em28xx_read_reg_req_len(dev, 0, EM2874_R51_IR,
259 					  msg, sizeof(msg));
260 	if (rc < 0)
261 		return rc;
262 
263 	/* Infrared toggle (Reg 0x51[7]) */
264 	poll_result->toggle_bit = (msg[0] >> 7);
265 
266 	/* Infrared read count (Reg 0x51[6:0] */
267 	poll_result->read_count = (msg[0] & 0x7f);
268 
269 	/*
270 	 * Remote Control Address (Reg 0x52)
271 	 * Remote Control Data (Reg 0x53-0x55)
272 	 */
273 	switch (ir->rc_proto) {
274 	case RC_PROTO_BIT_RC5:
275 		poll_result->protocol = RC_PROTO_RC5;
276 		poll_result->scancode = RC_SCANCODE_RC5(msg[1], msg[2]);
277 		break;
278 
279 	case RC_PROTO_BIT_NEC:
280 		poll_result->scancode = msg[1] << 8 | msg[2];
281 		if ((msg[3] ^ msg[4]) != 0xff) {	/* 32 bits NEC */
282 			poll_result->protocol = RC_PROTO_NEC32;
283 			poll_result->scancode = RC_SCANCODE_NEC32((msg[1] << 24) |
284 								  (msg[2] << 16) |
285 								  (msg[3] << 8)  |
286 								  (msg[4]));
287 		} else if ((msg[1] ^ msg[2]) != 0xff) {	/* 24 bits NEC */
288 			poll_result->protocol = RC_PROTO_NECX;
289 			poll_result->scancode = RC_SCANCODE_NECX(msg[1] << 8 |
290 								 msg[2], msg[3]);
291 		} else {				/* Normal NEC */
292 			poll_result->protocol = RC_PROTO_NEC;
293 			poll_result->scancode = RC_SCANCODE_NEC(msg[1], msg[3]);
294 		}
295 		break;
296 
297 	case RC_PROTO_BIT_RC6_0:
298 		poll_result->protocol = RC_PROTO_RC6_0;
299 		poll_result->scancode = RC_SCANCODE_RC6_0(msg[1], msg[2]);
300 		break;
301 
302 	default:
303 		poll_result->protocol = RC_PROTO_UNKNOWN;
304 		poll_result->scancode = (msg[1] << 24) | (msg[2] << 16) |
305 					(msg[3] << 8)  | msg[4];
306 		break;
307 	}
308 
309 	return 0;
310 }
311 
312 /*
313  * Polling code for em28xx
314  */
315 
316 static int em28xx_i2c_ir_handle_key(struct em28xx_IR *ir)
317 {
318 	static u32 scancode;
319 	enum rc_proto protocol;
320 	int rc;
321 
322 	rc = ir->get_key_i2c(ir->i2c_client, &protocol, &scancode);
323 	if (rc < 0) {
324 		dprintk("ir->get_key_i2c() failed: %d\n", rc);
325 		return rc;
326 	}
327 
328 	if (rc) {
329 		dprintk("%s: proto = 0x%04x, scancode = 0x%04x\n",
330 			__func__, protocol, scancode);
331 		rc_keydown(ir->rc, protocol, scancode, 0);
332 	}
333 	return 0;
334 }
335 
336 static void em28xx_ir_handle_key(struct em28xx_IR *ir)
337 {
338 	int result;
339 	struct em28xx_ir_poll_result poll_result;
340 
341 	/* read the registers containing the IR status */
342 	result = ir->get_key(ir, &poll_result);
343 	if (unlikely(result < 0)) {
344 		dprintk("ir->get_key() failed: %d\n", result);
345 		return;
346 	}
347 
348 	if (unlikely(poll_result.read_count != ir->last_readcount)) {
349 		dprintk("%s: toggle: %d, count: %d, key 0x%04x\n", __func__,
350 			poll_result.toggle_bit, poll_result.read_count,
351 			poll_result.scancode);
352 		if (ir->full_code)
353 			rc_keydown(ir->rc,
354 				   poll_result.protocol,
355 				   poll_result.scancode,
356 				   poll_result.toggle_bit);
357 		else
358 			rc_keydown(ir->rc,
359 				   RC_PROTO_UNKNOWN,
360 				   poll_result.scancode & 0xff,
361 				   poll_result.toggle_bit);
362 
363 		if (ir->dev->chip_id == CHIP_ID_EM2874 ||
364 		    ir->dev->chip_id == CHIP_ID_EM2884)
365 			/*
366 			 * The em2874 clears the readcount field every time the
367 			 * register is read.  The em2860/2880 datasheet says
368 			 * that it is supposed to clear the readcount, but it
369 			 * doesn't. So with the em2874, we are looking for a
370 			 * non-zero read count as opposed to a readcount
371 			 * that is incrementing
372 			 */
373 			ir->last_readcount = 0;
374 		else
375 			ir->last_readcount = poll_result.read_count;
376 	}
377 }
378 
379 static void em28xx_ir_work(struct work_struct *work)
380 {
381 	struct em28xx_IR *ir = container_of(work, struct em28xx_IR, work.work);
382 
383 	if (ir->i2c_client) /* external i2c device */
384 		em28xx_i2c_ir_handle_key(ir);
385 	else /* internal device */
386 		em28xx_ir_handle_key(ir);
387 	schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
388 }
389 
390 static int em28xx_ir_start(struct rc_dev *rc)
391 {
392 	struct em28xx_IR *ir = rc->priv;
393 
394 	INIT_DELAYED_WORK(&ir->work, em28xx_ir_work);
395 	schedule_delayed_work(&ir->work, 0);
396 
397 	return 0;
398 }
399 
400 static void em28xx_ir_stop(struct rc_dev *rc)
401 {
402 	struct em28xx_IR *ir = rc->priv;
403 
404 	cancel_delayed_work_sync(&ir->work);
405 }
406 
407 static int em2860_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_proto)
408 {
409 	struct em28xx_IR *ir = rc_dev->priv;
410 	struct em28xx *dev = ir->dev;
411 
412 	/* Adjust xclk based on IR table for RC5/NEC tables */
413 	if (*rc_proto & RC_PROTO_BIT_RC5) {
414 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
415 		ir->full_code = 1;
416 		*rc_proto = RC_PROTO_BIT_RC5;
417 	} else if (*rc_proto & RC_PROTO_BIT_NEC) {
418 		dev->board.xclk &= ~EM28XX_XCLK_IR_RC5_MODE;
419 		ir->full_code = 1;
420 		*rc_proto = RC_PROTO_BIT_NEC;
421 	} else if (*rc_proto & RC_PROTO_BIT_UNKNOWN) {
422 		*rc_proto = RC_PROTO_BIT_UNKNOWN;
423 	} else {
424 		*rc_proto = ir->rc_proto;
425 		return -EINVAL;
426 	}
427 	em28xx_write_reg_bits(dev, EM28XX_R0F_XCLK, dev->board.xclk,
428 			      EM28XX_XCLK_IR_RC5_MODE);
429 
430 	ir->rc_proto = *rc_proto;
431 
432 	return 0;
433 }
434 
435 static int em2874_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_proto)
436 {
437 	struct em28xx_IR *ir = rc_dev->priv;
438 	struct em28xx *dev = ir->dev;
439 	u8 ir_config = EM2874_IR_RC5;
440 
441 	/* Adjust xclk and set type based on IR table for RC5/NEC/RC6 tables */
442 	if (*rc_proto & RC_PROTO_BIT_RC5) {
443 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
444 		ir->full_code = 1;
445 		*rc_proto = RC_PROTO_BIT_RC5;
446 	} else if (*rc_proto & RC_PROTO_BIT_NEC) {
447 		dev->board.xclk &= ~EM28XX_XCLK_IR_RC5_MODE;
448 		ir_config = EM2874_IR_NEC | EM2874_IR_NEC_NO_PARITY;
449 		ir->full_code = 1;
450 		*rc_proto = RC_PROTO_BIT_NEC;
451 	} else if (*rc_proto & RC_PROTO_BIT_RC6_0) {
452 		dev->board.xclk |= EM28XX_XCLK_IR_RC5_MODE;
453 		ir_config = EM2874_IR_RC6_MODE_0;
454 		ir->full_code = 1;
455 		*rc_proto = RC_PROTO_BIT_RC6_0;
456 	} else if (*rc_proto & RC_PROTO_BIT_UNKNOWN) {
457 		*rc_proto = RC_PROTO_BIT_UNKNOWN;
458 	} else {
459 		*rc_proto = ir->rc_proto;
460 		return -EINVAL;
461 	}
462 	em28xx_write_regs(dev, EM2874_R50_IR_CONFIG, &ir_config, 1);
463 	em28xx_write_reg_bits(dev, EM28XX_R0F_XCLK, dev->board.xclk,
464 			      EM28XX_XCLK_IR_RC5_MODE);
465 
466 	ir->rc_proto = *rc_proto;
467 
468 	return 0;
469 }
470 
471 static int em28xx_ir_change_protocol(struct rc_dev *rc_dev, u64 *rc_proto)
472 {
473 	struct em28xx_IR *ir = rc_dev->priv;
474 	struct em28xx *dev = ir->dev;
475 
476 	/* Setup the proper handler based on the chip */
477 	switch (dev->chip_id) {
478 	case CHIP_ID_EM2860:
479 	case CHIP_ID_EM2883:
480 		return em2860_ir_change_protocol(rc_dev, rc_proto);
481 	case CHIP_ID_EM2884:
482 	case CHIP_ID_EM2874:
483 	case CHIP_ID_EM28174:
484 	case CHIP_ID_EM28178:
485 		return em2874_ir_change_protocol(rc_dev, rc_proto);
486 	default:
487 		dev_err(&ir->dev->intf->dev,
488 			"Unrecognized em28xx chip id 0x%02x: IR not supported\n",
489 			dev->chip_id);
490 		return -EINVAL;
491 	}
492 }
493 
494 static int em28xx_probe_i2c_ir(struct em28xx *dev)
495 {
496 	int i = 0;
497 	/*
498 	 * Leadtek winfast tv USBII deluxe can find a non working IR-device
499 	 * at address 0x18, so if that address is needed for another board in
500 	 * the future, please put it after 0x1f.
501 	 */
502 	const unsigned short addr_list[] = {
503 		 0x1f, 0x30, 0x47, I2C_CLIENT_END
504 	};
505 
506 	while (addr_list[i] != I2C_CLIENT_END) {
507 		if (i2c_probe_func_quick_read(&dev->i2c_adap[dev->def_i2c_bus],
508 					      addr_list[i]) == 1)
509 			return addr_list[i];
510 		i++;
511 	}
512 
513 	return -ENODEV;
514 }
515 
516 /*
517  * Handle buttons
518  */
519 
520 static void em28xx_query_buttons(struct work_struct *work)
521 {
522 	struct em28xx *dev =
523 		container_of(work, struct em28xx, buttons_query_work.work);
524 	u8 i, j;
525 	int regval;
526 	bool is_pressed, was_pressed;
527 	const struct em28xx_led *led;
528 
529 	/* Poll and evaluate all addresses */
530 	for (i = 0; i < dev->num_button_polling_addresses; i++) {
531 		/* Read value from register */
532 		regval = em28xx_read_reg(dev, dev->button_polling_addresses[i]);
533 		if (regval < 0)
534 			continue;
535 		/* Check states of the buttons and act */
536 		j = 0;
537 		while (dev->board.buttons[j].role >= 0 &&
538 		       dev->board.buttons[j].role < EM28XX_NUM_BUTTON_ROLES) {
539 			const struct em28xx_button *button;
540 
541 			button = &dev->board.buttons[j];
542 
543 			/* Check if button uses the current address */
544 			if (button->reg_r != dev->button_polling_addresses[i]) {
545 				j++;
546 				continue;
547 			}
548 			/* Determine if button is and was pressed last time */
549 			is_pressed = regval & button->mask;
550 			was_pressed = dev->button_polling_last_values[i]
551 				       & button->mask;
552 			if (button->inverted) {
553 				is_pressed = !is_pressed;
554 				was_pressed = !was_pressed;
555 			}
556 			/* Clear button state (if needed) */
557 			if (is_pressed && button->reg_clearing)
558 				em28xx_write_reg(dev, button->reg_clearing,
559 						 (~regval & button->mask)
560 						    | (regval & ~button->mask));
561 			/* Handle button state */
562 			if (!is_pressed || was_pressed) {
563 				j++;
564 				continue;
565 			}
566 			switch (button->role) {
567 			case EM28XX_BUTTON_SNAPSHOT:
568 				/* Emulate the keypress */
569 				input_report_key(dev->sbutton_input_dev,
570 						 EM28XX_SNAPSHOT_KEY, 1);
571 				/* Unpress the key */
572 				input_report_key(dev->sbutton_input_dev,
573 						 EM28XX_SNAPSHOT_KEY, 0);
574 				break;
575 			case EM28XX_BUTTON_ILLUMINATION:
576 				led = em28xx_find_led(dev,
577 						      EM28XX_LED_ILLUMINATION);
578 				/* Switch illumination LED on/off */
579 				if (led)
580 					em28xx_toggle_reg_bits(dev,
581 							       led->gpio_reg,
582 							       led->gpio_mask);
583 				break;
584 			default:
585 				WARN_ONCE(1, "BUG: unhandled button role.");
586 			}
587 			/* Next button */
588 			j++;
589 		}
590 		/* Save current value for comparison during the next polling */
591 		dev->button_polling_last_values[i] = regval;
592 	}
593 	/* Schedule next poll */
594 	schedule_delayed_work(&dev->buttons_query_work,
595 			      msecs_to_jiffies(dev->button_polling_interval));
596 }
597 
598 static int em28xx_register_snapshot_button(struct em28xx *dev)
599 {
600 	struct usb_device *udev = interface_to_usbdev(dev->intf);
601 	struct input_dev *input_dev;
602 	int err;
603 
604 	dev_info(&dev->intf->dev, "Registering snapshot button...\n");
605 	input_dev = input_allocate_device();
606 	if (!input_dev)
607 		return -ENOMEM;
608 
609 	usb_make_path(udev, dev->snapshot_button_path,
610 		      sizeof(dev->snapshot_button_path));
611 	strlcat(dev->snapshot_button_path, "/sbutton",
612 		sizeof(dev->snapshot_button_path));
613 
614 	input_dev->name = "em28xx snapshot button";
615 	input_dev->phys = dev->snapshot_button_path;
616 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
617 	set_bit(EM28XX_SNAPSHOT_KEY, input_dev->keybit);
618 	input_dev->keycodesize = 0;
619 	input_dev->keycodemax = 0;
620 	input_dev->id.bustype = BUS_USB;
621 	input_dev->id.vendor = le16_to_cpu(udev->descriptor.idVendor);
622 	input_dev->id.product = le16_to_cpu(udev->descriptor.idProduct);
623 	input_dev->id.version = 1;
624 	input_dev->dev.parent = &dev->intf->dev;
625 
626 	err = input_register_device(input_dev);
627 	if (err) {
628 		dev_err(&dev->intf->dev, "input_register_device failed\n");
629 		input_free_device(input_dev);
630 		return err;
631 	}
632 
633 	dev->sbutton_input_dev = input_dev;
634 	return 0;
635 }
636 
637 static void em28xx_init_buttons(struct em28xx *dev)
638 {
639 	u8  i = 0, j = 0;
640 	bool addr_new = false;
641 
642 	dev->button_polling_interval = EM28XX_BUTTONS_DEBOUNCED_QUERY_INTERVAL;
643 	while (dev->board.buttons[i].role >= 0 &&
644 	       dev->board.buttons[i].role < EM28XX_NUM_BUTTON_ROLES) {
645 		const struct em28xx_button *button = &dev->board.buttons[i];
646 
647 		/* Check if polling address is already on the list */
648 		addr_new = true;
649 		for (j = 0; j < dev->num_button_polling_addresses; j++) {
650 			if (button->reg_r == dev->button_polling_addresses[j]) {
651 				addr_new = false;
652 				break;
653 			}
654 		}
655 		/* Check if max. number of polling addresses is exceeded */
656 		if (addr_new && dev->num_button_polling_addresses
657 					   >= EM28XX_NUM_BUTTON_ADDRESSES_MAX) {
658 			WARN_ONCE(1, "BUG: maximum number of button polling addresses exceeded.");
659 			goto next_button;
660 		}
661 		/* Button role specific checks and actions */
662 		if (button->role == EM28XX_BUTTON_SNAPSHOT) {
663 			/* Register input device */
664 			if (em28xx_register_snapshot_button(dev) < 0)
665 				goto next_button;
666 		} else if (button->role == EM28XX_BUTTON_ILLUMINATION) {
667 			/* Check sanity */
668 			if (!em28xx_find_led(dev, EM28XX_LED_ILLUMINATION)) {
669 				dev_err(&dev->intf->dev,
670 					"BUG: illumination button defined, but no illumination LED.\n");
671 				goto next_button;
672 			}
673 		}
674 		/* Add read address to list of polling addresses */
675 		if (addr_new) {
676 			unsigned int index = dev->num_button_polling_addresses;
677 
678 			dev->button_polling_addresses[index] = button->reg_r;
679 			dev->num_button_polling_addresses++;
680 		}
681 		/* Reduce polling interval if necessary */
682 		if (!button->reg_clearing)
683 			dev->button_polling_interval =
684 					 EM28XX_BUTTONS_VOLATILE_QUERY_INTERVAL;
685 next_button:
686 		/* Next button */
687 		i++;
688 	}
689 
690 	/* Start polling */
691 	if (dev->num_button_polling_addresses) {
692 		memset(dev->button_polling_last_values, 0,
693 		       EM28XX_NUM_BUTTON_ADDRESSES_MAX);
694 		schedule_delayed_work(&dev->buttons_query_work,
695 				      msecs_to_jiffies(dev->button_polling_interval));
696 	}
697 }
698 
699 static void em28xx_shutdown_buttons(struct em28xx *dev)
700 {
701 	/* Cancel polling */
702 	cancel_delayed_work_sync(&dev->buttons_query_work);
703 	/* Clear polling addresses list */
704 	dev->num_button_polling_addresses = 0;
705 	/* Deregister input devices */
706 	if (dev->sbutton_input_dev) {
707 		dev_info(&dev->intf->dev, "Deregistering snapshot button\n");
708 		input_unregister_device(dev->sbutton_input_dev);
709 		dev->sbutton_input_dev = NULL;
710 	}
711 }
712 
713 static int em28xx_ir_init(struct em28xx *dev)
714 {
715 	struct usb_device *udev = interface_to_usbdev(dev->intf);
716 	struct em28xx_IR *ir;
717 	struct rc_dev *rc;
718 	int err = -ENOMEM;
719 	u64 rc_proto;
720 	u16 i2c_rc_dev_addr = 0;
721 
722 	if (dev->is_audio_only) {
723 		/* Shouldn't initialize IR for this interface */
724 		return 0;
725 	}
726 
727 	kref_get(&dev->ref);
728 	INIT_DELAYED_WORK(&dev->buttons_query_work, em28xx_query_buttons);
729 
730 	if (dev->board.buttons)
731 		em28xx_init_buttons(dev);
732 
733 	if (dev->board.has_ir_i2c) {
734 		i2c_rc_dev_addr = em28xx_probe_i2c_ir(dev);
735 		if (!i2c_rc_dev_addr) {
736 			dev->board.has_ir_i2c = 0;
737 			dev_warn(&dev->intf->dev,
738 				 "No i2c IR remote control device found.\n");
739 			return -ENODEV;
740 		}
741 	}
742 
743 	if (!dev->board.ir_codes && !dev->board.has_ir_i2c) {
744 		/* No remote control support */
745 		dev_warn(&dev->intf->dev,
746 			 "Remote control support is not available for this card.\n");
747 		return 0;
748 	}
749 
750 	dev_info(&dev->intf->dev, "Registering input extension\n");
751 
752 	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
753 	if (!ir)
754 		return -ENOMEM;
755 	rc = rc_allocate_device(RC_DRIVER_SCANCODE);
756 	if (!rc)
757 		goto error;
758 
759 	/* record handles to ourself */
760 	ir->dev = dev;
761 	dev->ir = ir;
762 	ir->rc = rc;
763 
764 	rc->priv = ir;
765 	rc->open = em28xx_ir_start;
766 	rc->close = em28xx_ir_stop;
767 
768 	if (dev->board.has_ir_i2c) {	/* external i2c device */
769 		switch (dev->model) {
770 		case EM2800_BOARD_TERRATEC_CINERGY_200:
771 		case EM2820_BOARD_TERRATEC_CINERGY_250:
772 			rc->map_name = RC_MAP_EM_TERRATEC;
773 			ir->get_key_i2c = em28xx_get_key_terratec;
774 			break;
775 		case EM2820_BOARD_PINNACLE_USB_2:
776 			rc->map_name = RC_MAP_PINNACLE_GREY;
777 			ir->get_key_i2c = em28xx_get_key_pinnacle_usb_grey;
778 			break;
779 		case EM2820_BOARD_HAUPPAUGE_WINTV_USB_2:
780 			rc->map_name = RC_MAP_HAUPPAUGE;
781 			ir->get_key_i2c = em28xx_get_key_em_haup;
782 			rc->allowed_protocols = RC_PROTO_BIT_RC5;
783 			break;
784 		case EM2820_BOARD_LEADTEK_WINFAST_USBII_DELUXE:
785 			rc->map_name = RC_MAP_WINFAST_USBII_DELUXE;
786 			ir->get_key_i2c = em28xx_get_key_winfast_usbii_deluxe;
787 			break;
788 		default:
789 			err = -ENODEV;
790 			goto error;
791 		}
792 
793 		ir->i2c_client = kzalloc(sizeof(*ir->i2c_client), GFP_KERNEL);
794 		if (!ir->i2c_client)
795 			goto error;
796 		ir->i2c_client->adapter = &ir->dev->i2c_adap[dev->def_i2c_bus];
797 		ir->i2c_client->addr = i2c_rc_dev_addr;
798 		ir->i2c_client->flags = 0;
799 		/* NOTE: all other fields of i2c_client are unused */
800 	} else {	/* internal device */
801 		switch (dev->chip_id) {
802 		case CHIP_ID_EM2860:
803 		case CHIP_ID_EM2883:
804 			rc->allowed_protocols = RC_PROTO_BIT_RC5 |
805 						RC_PROTO_BIT_NEC;
806 			ir->get_key = default_polling_getkey;
807 			break;
808 		case CHIP_ID_EM2884:
809 		case CHIP_ID_EM2874:
810 		case CHIP_ID_EM28174:
811 		case CHIP_ID_EM28178:
812 			ir->get_key = em2874_polling_getkey;
813 			rc->allowed_protocols = RC_PROTO_BIT_RC5 |
814 				RC_PROTO_BIT_NEC | RC_PROTO_BIT_NECX |
815 				RC_PROTO_BIT_NEC32 | RC_PROTO_BIT_RC6_0;
816 			break;
817 		default:
818 			err = -ENODEV;
819 			goto error;
820 		}
821 
822 		rc->change_protocol = em28xx_ir_change_protocol;
823 		rc->map_name = dev->board.ir_codes;
824 
825 		/* By default, keep protocol field untouched */
826 		rc_proto = RC_PROTO_BIT_UNKNOWN;
827 		err = em28xx_ir_change_protocol(rc, &rc_proto);
828 		if (err)
829 			goto error;
830 	}
831 
832 	/* This is how often we ask the chip for IR information */
833 	ir->polling = 100; /* ms */
834 
835 	/* init input device */
836 	snprintf(ir->name, sizeof(ir->name), "%s IR",
837 		 dev_name(&dev->intf->dev));
838 
839 	usb_make_path(udev, ir->phys, sizeof(ir->phys));
840 	strlcat(ir->phys, "/input0", sizeof(ir->phys));
841 
842 	rc->device_name = ir->name;
843 	rc->input_phys = ir->phys;
844 	rc->input_id.bustype = BUS_USB;
845 	rc->input_id.version = 1;
846 	rc->input_id.vendor = le16_to_cpu(udev->descriptor.idVendor);
847 	rc->input_id.product = le16_to_cpu(udev->descriptor.idProduct);
848 	rc->dev.parent = &dev->intf->dev;
849 	rc->driver_name = MODULE_NAME;
850 
851 	/* all done */
852 	err = rc_register_device(rc);
853 	if (err)
854 		goto error;
855 
856 	dev_info(&dev->intf->dev, "Input extension successfully initialized\n");
857 
858 	return 0;
859 
860 error:
861 	kfree(ir->i2c_client);
862 	dev->ir = NULL;
863 	rc_free_device(rc);
864 	kfree(ir);
865 	return err;
866 }
867 
868 static int em28xx_ir_fini(struct em28xx *dev)
869 {
870 	struct em28xx_IR *ir = dev->ir;
871 
872 	if (dev->is_audio_only) {
873 		/* Shouldn't initialize IR for this interface */
874 		return 0;
875 	}
876 
877 	dev_info(&dev->intf->dev, "Closing input extension\n");
878 
879 	em28xx_shutdown_buttons(dev);
880 
881 	/* skip detach on non attached boards */
882 	if (!ir)
883 		goto ref_put;
884 
885 	rc_unregister_device(ir->rc);
886 
887 	kfree(ir->i2c_client);
888 
889 	/* done */
890 	kfree(ir);
891 	dev->ir = NULL;
892 
893 ref_put:
894 	kref_put(&dev->ref, em28xx_free_device);
895 
896 	return 0;
897 }
898 
899 static int em28xx_ir_suspend(struct em28xx *dev)
900 {
901 	struct em28xx_IR *ir = dev->ir;
902 
903 	if (dev->is_audio_only)
904 		return 0;
905 
906 	dev_info(&dev->intf->dev, "Suspending input extension\n");
907 	if (ir)
908 		cancel_delayed_work_sync(&ir->work);
909 	cancel_delayed_work_sync(&dev->buttons_query_work);
910 	/*
911 	 * is canceling delayed work sufficient or does the rc event
912 	 * kthread needs stopping? kthread is stopped in
913 	 * ir_raw_event_unregister()
914 	 */
915 	return 0;
916 }
917 
918 static int em28xx_ir_resume(struct em28xx *dev)
919 {
920 	struct em28xx_IR *ir = dev->ir;
921 
922 	if (dev->is_audio_only)
923 		return 0;
924 
925 	dev_info(&dev->intf->dev, "Resuming input extension\n");
926 	/*
927 	 * if suspend calls ir_raw_event_unregister(), the should call
928 	 * ir_raw_event_register()
929 	 */
930 	if (ir)
931 		schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
932 	if (dev->num_button_polling_addresses)
933 		schedule_delayed_work(&dev->buttons_query_work,
934 				      msecs_to_jiffies(dev->button_polling_interval));
935 	return 0;
936 }
937 
938 static struct em28xx_ops rc_ops = {
939 	.id   = EM28XX_RC,
940 	.name = "Em28xx Input Extension",
941 	.init = em28xx_ir_init,
942 	.fini = em28xx_ir_fini,
943 	.suspend = em28xx_ir_suspend,
944 	.resume = em28xx_ir_resume,
945 };
946 
947 static int __init em28xx_rc_register(void)
948 {
949 	return em28xx_register_extension(&rc_ops);
950 }
951 
952 static void __exit em28xx_rc_unregister(void)
953 {
954 	em28xx_unregister_extension(&rc_ops);
955 }
956 
957 MODULE_LICENSE("GPL v2");
958 MODULE_AUTHOR("Mauro Carvalho Chehab");
959 MODULE_DESCRIPTION(DRIVER_DESC " - input interface");
960 MODULE_VERSION(EM28XX_VERSION);
961 
962 module_init(em28xx_rc_register);
963 module_exit(em28xx_rc_unregister);
964