1 /*
2  * keyspan_remote: USB driver for the Keyspan DMR
3  *
4  * Copyright (C) 2005 Zymeta Corporation - Michael Downey (downey@zymeta.com)
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License as
8  *	published by the Free Software Foundation, version 2.
9  *
10  * This driver has been put together with the support of Innosys, Inc.
11  * and Keyspan, Inc the manufacturers of the Keyspan USB DMR product.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/usb/input.h>
19 
20 #define DRIVER_VERSION	"v0.1"
21 #define DRIVER_AUTHOR	"Michael Downey <downey@zymeta.com>"
22 #define DRIVER_DESC	"Driver for the USB Keyspan remote control."
23 #define DRIVER_LICENSE	"GPL"
24 
25 /* Parameters that can be passed to the driver. */
26 static int debug;
27 module_param(debug, int, 0444);
28 MODULE_PARM_DESC(debug, "Enable extra debug messages and information");
29 
30 /* Vendor and product ids */
31 #define USB_KEYSPAN_VENDOR_ID		0x06CD
32 #define USB_KEYSPAN_PRODUCT_UIA11	0x0202
33 
34 /* Defines for converting the data from the remote. */
35 #define ZERO		0x18
36 #define ZERO_MASK	0x1F	/* 5 bits for a 0 */
37 #define ONE		0x3C
38 #define ONE_MASK	0x3F	/* 6 bits for a 1 */
39 #define SYNC		0x3F80
40 #define SYNC_MASK	0x3FFF	/* 14 bits for a SYNC sequence */
41 #define STOP		0x00
42 #define STOP_MASK	0x1F	/* 5 bits for the STOP sequence */
43 #define GAP		0xFF
44 
45 #define RECV_SIZE	8	/* The UIA-11 type have a 8 byte limit. */
46 
47 /*
48  * Table that maps the 31 possible keycodes to input keys.
49  * Currently there are 15 and 17 button models so RESERVED codes
50  * are blank areas in the mapping.
51  */
52 static const unsigned short keyspan_key_table[] = {
53 	KEY_RESERVED,		/* 0 is just a place holder. */
54 	KEY_RESERVED,
55 	KEY_STOP,
56 	KEY_PLAYCD,
57 	KEY_RESERVED,
58 	KEY_PREVIOUSSONG,
59 	KEY_REWIND,
60 	KEY_FORWARD,
61 	KEY_NEXTSONG,
62 	KEY_RESERVED,
63 	KEY_RESERVED,
64 	KEY_RESERVED,
65 	KEY_PAUSE,
66 	KEY_VOLUMEUP,
67 	KEY_RESERVED,
68 	KEY_RESERVED,
69 	KEY_RESERVED,
70 	KEY_VOLUMEDOWN,
71 	KEY_RESERVED,
72 	KEY_UP,
73 	KEY_RESERVED,
74 	KEY_MUTE,
75 	KEY_LEFT,
76 	KEY_ENTER,
77 	KEY_RIGHT,
78 	KEY_RESERVED,
79 	KEY_RESERVED,
80 	KEY_DOWN,
81 	KEY_RESERVED,
82 	KEY_KPASTERISK,
83 	KEY_RESERVED,
84 	KEY_MENU
85 };
86 
87 /* table of devices that work with this driver */
88 static struct usb_device_id keyspan_table[] = {
89 	{ USB_DEVICE(USB_KEYSPAN_VENDOR_ID, USB_KEYSPAN_PRODUCT_UIA11) },
90 	{ }					/* Terminating entry */
91 };
92 
93 /* Structure to store all the real stuff that a remote sends to us. */
94 struct keyspan_message {
95 	u16	system;
96 	u8	button;
97 	u8	toggle;
98 };
99 
100 /* Structure used for all the bit testing magic needed to be done. */
101 struct bit_tester {
102 	u32	tester;
103 	int	len;
104 	int	pos;
105 	int	bits_left;
106 	u8	buffer[32];
107 };
108 
109 /* Structure to hold all of our driver specific stuff */
110 struct usb_keyspan {
111 	char				name[128];
112 	char				phys[64];
113 	unsigned short			keymap[ARRAY_SIZE(keyspan_key_table)];
114 	struct usb_device		*udev;
115 	struct input_dev		*input;
116 	struct usb_interface		*interface;
117 	struct usb_endpoint_descriptor	*in_endpoint;
118 	struct urb*			irq_urb;
119 	int				open;
120 	dma_addr_t			in_dma;
121 	unsigned char			*in_buffer;
122 
123 	/* variables used to parse messages from remote. */
124 	struct bit_tester		data;
125 	int				stage;
126 	int				toggle;
127 };
128 
129 static struct usb_driver keyspan_driver;
130 
131 /*
132  * Debug routine that prints out what we've received from the remote.
133  */
134 static void keyspan_print(struct usb_keyspan* dev) /*unsigned char* data)*/
135 {
136 	char codes[4 * RECV_SIZE];
137 	int i;
138 
139 	for (i = 0; i < RECV_SIZE; i++)
140 		snprintf(codes + i * 3, 4, "%02x ", dev->in_buffer[i]);
141 
142 	dev_info(&dev->udev->dev, "%s\n", codes);
143 }
144 
145 /*
146  * Routine that manages the bit_tester structure.  It makes sure that there are
147  * at least bits_needed bits loaded into the tester.
148  */
149 static int keyspan_load_tester(struct usb_keyspan* dev, int bits_needed)
150 {
151 	if (dev->data.bits_left >= bits_needed)
152 		return 0;
153 
154 	/*
155 	 * Somehow we've missed the last message. The message will be repeated
156 	 * though so it's not too big a deal
157 	 */
158 	if (dev->data.pos >= dev->data.len) {
159 		dev_dbg(&dev->interface->dev,
160 			"%s - Error ran out of data. pos: %d, len: %d\n",
161 			__func__, dev->data.pos, dev->data.len);
162 		return -1;
163 	}
164 
165 	/* Load as much as we can into the tester. */
166 	while ((dev->data.bits_left + 7 < (sizeof(dev->data.tester) * 8)) &&
167 	       (dev->data.pos < dev->data.len)) {
168 		dev->data.tester += (dev->data.buffer[dev->data.pos++] << dev->data.bits_left);
169 		dev->data.bits_left += 8;
170 	}
171 
172 	return 0;
173 }
174 
175 static void keyspan_report_button(struct usb_keyspan *remote, int button, int press)
176 {
177 	struct input_dev *input = remote->input;
178 
179 	input_event(input, EV_MSC, MSC_SCAN, button);
180 	input_report_key(input, remote->keymap[button], press);
181 	input_sync(input);
182 }
183 
184 /*
185  * Routine that handles all the logic needed to parse out the message from the remote.
186  */
187 static void keyspan_check_data(struct usb_keyspan *remote)
188 {
189 	int i;
190 	int found = 0;
191 	struct keyspan_message message;
192 
193 	switch(remote->stage) {
194 	case 0:
195 		/*
196 		 * In stage 0 we want to find the start of a message.  The remote sends a 0xFF as filler.
197 		 * So the first byte that isn't a FF should be the start of a new message.
198 		 */
199 		for (i = 0; i < RECV_SIZE && remote->in_buffer[i] == GAP; ++i);
200 
201 		if (i < RECV_SIZE) {
202 			memcpy(remote->data.buffer, remote->in_buffer, RECV_SIZE);
203 			remote->data.len = RECV_SIZE;
204 			remote->data.pos = 0;
205 			remote->data.tester = 0;
206 			remote->data.bits_left = 0;
207 			remote->stage = 1;
208 		}
209 		break;
210 
211 	case 1:
212 		/*
213 		 * Stage 1 we should have 16 bytes and should be able to detect a
214 		 * SYNC.  The SYNC is 14 bits, 7 0's and then 7 1's.
215 		 */
216 		memcpy(remote->data.buffer + remote->data.len, remote->in_buffer, RECV_SIZE);
217 		remote->data.len += RECV_SIZE;
218 
219 		found = 0;
220 		while ((remote->data.bits_left >= 14 || remote->data.pos < remote->data.len) && !found) {
221 			for (i = 0; i < 8; ++i) {
222 				if (keyspan_load_tester(remote, 14) != 0) {
223 					remote->stage = 0;
224 					return;
225 				}
226 
227 				if ((remote->data.tester & SYNC_MASK) == SYNC) {
228 					remote->data.tester = remote->data.tester >> 14;
229 					remote->data.bits_left -= 14;
230 					found = 1;
231 					break;
232 				} else {
233 					remote->data.tester = remote->data.tester >> 1;
234 					--remote->data.bits_left;
235 				}
236 			}
237 		}
238 
239 		if (!found) {
240 			remote->stage = 0;
241 			remote->data.len = 0;
242 		} else {
243 			remote->stage = 2;
244 		}
245 		break;
246 
247 	case 2:
248 		/*
249 		 * Stage 2 we should have 24 bytes which will be enough for a full
250 		 * message.  We need to parse out the system code, button code,
251 		 * toggle code, and stop.
252 		 */
253 		memcpy(remote->data.buffer + remote->data.len, remote->in_buffer, RECV_SIZE);
254 		remote->data.len += RECV_SIZE;
255 
256 		message.system = 0;
257 		for (i = 0; i < 9; i++) {
258 			keyspan_load_tester(remote, 6);
259 
260 			if ((remote->data.tester & ZERO_MASK) == ZERO) {
261 				message.system = message.system << 1;
262 				remote->data.tester = remote->data.tester >> 5;
263 				remote->data.bits_left -= 5;
264 			} else if ((remote->data.tester & ONE_MASK) == ONE) {
265 				message.system = (message.system << 1) + 1;
266 				remote->data.tester = remote->data.tester >> 6;
267 				remote->data.bits_left -= 6;
268 			} else {
269 				dev_err(&remote->interface->dev,
270 					"%s - Unknown sequence found in system data.\n",
271 					__func__);
272 				remote->stage = 0;
273 				return;
274 			}
275 		}
276 
277 		message.button = 0;
278 		for (i = 0; i < 5; i++) {
279 			keyspan_load_tester(remote, 6);
280 
281 			if ((remote->data.tester & ZERO_MASK) == ZERO) {
282 				message.button = message.button << 1;
283 				remote->data.tester = remote->data.tester >> 5;
284 				remote->data.bits_left -= 5;
285 			} else if ((remote->data.tester & ONE_MASK) == ONE) {
286 				message.button = (message.button << 1) + 1;
287 				remote->data.tester = remote->data.tester >> 6;
288 				remote->data.bits_left -= 6;
289 			} else {
290 				dev_err(&remote->interface->dev,
291 					"%s - Unknown sequence found in button data.\n",
292 					__func__);
293 				remote->stage = 0;
294 				return;
295 			}
296 		}
297 
298 		keyspan_load_tester(remote, 6);
299 		if ((remote->data.tester & ZERO_MASK) == ZERO) {
300 			message.toggle = 0;
301 			remote->data.tester = remote->data.tester >> 5;
302 			remote->data.bits_left -= 5;
303 		} else if ((remote->data.tester & ONE_MASK) == ONE) {
304 			message.toggle = 1;
305 			remote->data.tester = remote->data.tester >> 6;
306 			remote->data.bits_left -= 6;
307 		} else {
308 			dev_err(&remote->interface->dev,
309 				"%s - Error in message, invalid toggle.\n",
310 				__func__);
311 			remote->stage = 0;
312 			return;
313 		}
314 
315 		keyspan_load_tester(remote, 5);
316 		if ((remote->data.tester & STOP_MASK) == STOP) {
317 			remote->data.tester = remote->data.tester >> 5;
318 			remote->data.bits_left -= 5;
319 		} else {
320 			dev_err(&remote->interface->dev,
321 				"Bad message received, no stop bit found.\n");
322 		}
323 
324 		dev_dbg(&remote->interface->dev,
325 			"%s found valid message: system: %d, button: %d, toggle: %d\n",
326 			__func__, message.system, message.button, message.toggle);
327 
328 		if (message.toggle != remote->toggle) {
329 			keyspan_report_button(remote, message.button, 1);
330 			keyspan_report_button(remote, message.button, 0);
331 			remote->toggle = message.toggle;
332 		}
333 
334 		remote->stage = 0;
335 		break;
336 	}
337 }
338 
339 /*
340  * Routine for sending all the initialization messages to the remote.
341  */
342 static int keyspan_setup(struct usb_device* dev)
343 {
344 	int retval = 0;
345 
346 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
347 				 0x11, 0x40, 0x5601, 0x0, NULL, 0, 0);
348 	if (retval) {
349 		dev_dbg(&dev->dev, "%s - failed to set bit rate due to error: %d\n",
350 			__func__, retval);
351 		return(retval);
352 	}
353 
354 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
355 				 0x44, 0x40, 0x0, 0x0, NULL, 0, 0);
356 	if (retval) {
357 		dev_dbg(&dev->dev, "%s - failed to set resume sensitivity due to error: %d\n",
358 			__func__, retval);
359 		return(retval);
360 	}
361 
362 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
363 				 0x22, 0x40, 0x0, 0x0, NULL, 0, 0);
364 	if (retval) {
365 		dev_dbg(&dev->dev, "%s - failed to turn receive on due to error: %d\n",
366 			__func__, retval);
367 		return(retval);
368 	}
369 
370 	dev_dbg(&dev->dev, "%s - Setup complete.\n", __func__);
371 	return(retval);
372 }
373 
374 /*
375  * Routine used to handle a new message that has come in.
376  */
377 static void keyspan_irq_recv(struct urb *urb)
378 {
379 	struct usb_keyspan *dev = urb->context;
380 	int retval;
381 
382 	/* Check our status in case we need to bail out early. */
383 	switch (urb->status) {
384 	case 0:
385 		break;
386 
387 	/* Device went away so don't keep trying to read from it. */
388 	case -ECONNRESET:
389 	case -ENOENT:
390 	case -ESHUTDOWN:
391 		return;
392 
393 	default:
394 		goto resubmit;
395 	}
396 
397 	if (debug)
398 		keyspan_print(dev);
399 
400 	keyspan_check_data(dev);
401 
402 resubmit:
403 	retval = usb_submit_urb(urb, GFP_ATOMIC);
404 	if (retval)
405 		dev_err(&dev->interface->dev,
406 			"%s - usb_submit_urb failed with result: %d\n",
407 			__func__, retval);
408 }
409 
410 static int keyspan_open(struct input_dev *dev)
411 {
412 	struct usb_keyspan *remote = input_get_drvdata(dev);
413 
414 	remote->irq_urb->dev = remote->udev;
415 	if (usb_submit_urb(remote->irq_urb, GFP_KERNEL))
416 		return -EIO;
417 
418 	return 0;
419 }
420 
421 static void keyspan_close(struct input_dev *dev)
422 {
423 	struct usb_keyspan *remote = input_get_drvdata(dev);
424 
425 	usb_kill_urb(remote->irq_urb);
426 }
427 
428 static struct usb_endpoint_descriptor *keyspan_get_in_endpoint(struct usb_host_interface *iface)
429 {
430 
431 	struct usb_endpoint_descriptor *endpoint;
432 	int i;
433 
434 	for (i = 0; i < iface->desc.bNumEndpoints; ++i) {
435 		endpoint = &iface->endpoint[i].desc;
436 
437 		if (usb_endpoint_is_int_in(endpoint)) {
438 			/* we found our interrupt in endpoint */
439 			return endpoint;
440 		}
441 	}
442 
443 	return NULL;
444 }
445 
446 /*
447  * Routine that sets up the driver to handle a specific USB device detected on the bus.
448  */
449 static int keyspan_probe(struct usb_interface *interface, const struct usb_device_id *id)
450 {
451 	struct usb_device *udev = interface_to_usbdev(interface);
452 	struct usb_endpoint_descriptor *endpoint;
453 	struct usb_keyspan *remote;
454 	struct input_dev *input_dev;
455 	int i, error;
456 
457 	endpoint = keyspan_get_in_endpoint(interface->cur_altsetting);
458 	if (!endpoint)
459 		return -ENODEV;
460 
461 	remote = kzalloc(sizeof(*remote), GFP_KERNEL);
462 	input_dev = input_allocate_device();
463 	if (!remote || !input_dev) {
464 		error = -ENOMEM;
465 		goto fail1;
466 	}
467 
468 	remote->udev = udev;
469 	remote->input = input_dev;
470 	remote->interface = interface;
471 	remote->in_endpoint = endpoint;
472 	remote->toggle = -1;	/* Set to -1 so we will always not match the toggle from the first remote message. */
473 
474 	remote->in_buffer = usb_alloc_coherent(udev, RECV_SIZE, GFP_ATOMIC, &remote->in_dma);
475 	if (!remote->in_buffer) {
476 		error = -ENOMEM;
477 		goto fail1;
478 	}
479 
480 	remote->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
481 	if (!remote->irq_urb) {
482 		error = -ENOMEM;
483 		goto fail2;
484 	}
485 
486 	error = keyspan_setup(udev);
487 	if (error) {
488 		error = -ENODEV;
489 		goto fail3;
490 	}
491 
492 	if (udev->manufacturer)
493 		strlcpy(remote->name, udev->manufacturer, sizeof(remote->name));
494 
495 	if (udev->product) {
496 		if (udev->manufacturer)
497 			strlcat(remote->name, " ", sizeof(remote->name));
498 		strlcat(remote->name, udev->product, sizeof(remote->name));
499 	}
500 
501 	if (!strlen(remote->name))
502 		snprintf(remote->name, sizeof(remote->name),
503 			 "USB Keyspan Remote %04x:%04x",
504 			 le16_to_cpu(udev->descriptor.idVendor),
505 			 le16_to_cpu(udev->descriptor.idProduct));
506 
507 	usb_make_path(udev, remote->phys, sizeof(remote->phys));
508 	strlcat(remote->phys, "/input0", sizeof(remote->phys));
509 	memcpy(remote->keymap, keyspan_key_table, sizeof(remote->keymap));
510 
511 	input_dev->name = remote->name;
512 	input_dev->phys = remote->phys;
513 	usb_to_input_id(udev, &input_dev->id);
514 	input_dev->dev.parent = &interface->dev;
515 	input_dev->keycode = remote->keymap;
516 	input_dev->keycodesize = sizeof(unsigned short);
517 	input_dev->keycodemax = ARRAY_SIZE(remote->keymap);
518 
519 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
520 	__set_bit(EV_KEY, input_dev->evbit);
521 	for (i = 0; i < ARRAY_SIZE(keyspan_key_table); i++)
522 		__set_bit(keyspan_key_table[i], input_dev->keybit);
523 	__clear_bit(KEY_RESERVED, input_dev->keybit);
524 
525 	input_set_drvdata(input_dev, remote);
526 
527 	input_dev->open = keyspan_open;
528 	input_dev->close = keyspan_close;
529 
530 	/*
531 	 * Initialize the URB to access the device.
532 	 * The urb gets sent to the device in keyspan_open()
533 	 */
534 	usb_fill_int_urb(remote->irq_urb,
535 			 remote->udev,
536 			 usb_rcvintpipe(remote->udev, endpoint->bEndpointAddress),
537 			 remote->in_buffer, RECV_SIZE, keyspan_irq_recv, remote,
538 			 endpoint->bInterval);
539 	remote->irq_urb->transfer_dma = remote->in_dma;
540 	remote->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
541 
542 	/* we can register the device now, as it is ready */
543 	error = input_register_device(remote->input);
544 	if (error)
545 		goto fail3;
546 
547 	/* save our data pointer in this interface device */
548 	usb_set_intfdata(interface, remote);
549 
550 	return 0;
551 
552  fail3:	usb_free_urb(remote->irq_urb);
553  fail2:	usb_free_coherent(udev, RECV_SIZE, remote->in_buffer, remote->in_dma);
554  fail1:	kfree(remote);
555 	input_free_device(input_dev);
556 
557 	return error;
558 }
559 
560 /*
561  * Routine called when a device is disconnected from the USB.
562  */
563 static void keyspan_disconnect(struct usb_interface *interface)
564 {
565 	struct usb_keyspan *remote;
566 
567 	remote = usb_get_intfdata(interface);
568 	usb_set_intfdata(interface, NULL);
569 
570 	if (remote) {	/* We have a valid driver structure so clean up everything we allocated. */
571 		input_unregister_device(remote->input);
572 		usb_kill_urb(remote->irq_urb);
573 		usb_free_urb(remote->irq_urb);
574 		usb_free_coherent(remote->udev, RECV_SIZE, remote->in_buffer, remote->in_dma);
575 		kfree(remote);
576 	}
577 }
578 
579 /*
580  * Standard driver set up sections
581  */
582 static struct usb_driver keyspan_driver =
583 {
584 	.name =		"keyspan_remote",
585 	.probe =	keyspan_probe,
586 	.disconnect =	keyspan_disconnect,
587 	.id_table =	keyspan_table
588 };
589 
590 module_usb_driver(keyspan_driver);
591 
592 MODULE_DEVICE_TABLE(usb, keyspan_table);
593 MODULE_AUTHOR(DRIVER_AUTHOR);
594 MODULE_DESCRIPTION(DRIVER_DESC);
595 MODULE_LICENSE(DRIVER_LICENSE);
596