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