1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * keyspan_remote: USB driver for the Keyspan DMR
4 *
5 * Copyright (C) 2005 Zymeta Corporation - Michael Downey (downey@zymeta.com)
6 *
7 * This driver has been put together with the support of Innosys, Inc.
8 * and Keyspan, Inc the manufacturers of the Keyspan USB DMR product.
9 */
10
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/slab.h>
14#include <linux/module.h>
15#include <linux/usb/input.h>
16
17/* Parameters that can be passed to the driver. */
18static int debug;
19module_param(debug, int, 0444);
20MODULE_PARM_DESC(debug, "Enable extra debug messages and information");
21
22/* Vendor and product ids */
23#define USB_KEYSPAN_VENDOR_ID		0x06CD
24#define USB_KEYSPAN_PRODUCT_UIA11	0x0202
25
26/* Defines for converting the data from the remote. */
27#define ZERO		0x18
28#define ZERO_MASK	0x1F	/* 5 bits for a 0 */
29#define ONE		0x3C
30#define ONE_MASK	0x3F	/* 6 bits for a 1 */
31#define SYNC		0x3F80
32#define SYNC_MASK	0x3FFF	/* 14 bits for a SYNC sequence */
33#define STOP		0x00
34#define STOP_MASK	0x1F	/* 5 bits for the STOP sequence */
35#define GAP		0xFF
36
37#define RECV_SIZE	8	/* The UIA-11 type have a 8 byte limit. */
38
39/*
40 * Table that maps the 31 possible keycodes to input keys.
41 * Currently there are 15 and 17 button models so RESERVED codes
42 * are blank areas in the mapping.
43 */
44static const unsigned short keyspan_key_table[] = {
45	KEY_RESERVED,		/* 0 is just a place holder. */
46	KEY_RESERVED,
47	KEY_STOP,
48	KEY_PLAYCD,
49	KEY_RESERVED,
50	KEY_PREVIOUSSONG,
51	KEY_REWIND,
52	KEY_FORWARD,
53	KEY_NEXTSONG,
54	KEY_RESERVED,
55	KEY_RESERVED,
56	KEY_RESERVED,
57	KEY_PAUSE,
58	KEY_VOLUMEUP,
59	KEY_RESERVED,
60	KEY_RESERVED,
61	KEY_RESERVED,
62	KEY_VOLUMEDOWN,
63	KEY_RESERVED,
64	KEY_UP,
65	KEY_RESERVED,
66	KEY_MUTE,
67	KEY_LEFT,
68	KEY_ENTER,
69	KEY_RIGHT,
70	KEY_RESERVED,
71	KEY_RESERVED,
72	KEY_DOWN,
73	KEY_RESERVED,
74	KEY_KPASTERISK,
75	KEY_RESERVED,
76	KEY_MENU
77};
78
79/* table of devices that work with this driver */
80static const struct usb_device_id keyspan_table[] = {
81	{ USB_DEVICE(USB_KEYSPAN_VENDOR_ID, USB_KEYSPAN_PRODUCT_UIA11) },
82	{ }					/* Terminating entry */
83};
84
85/* Structure to store all the real stuff that a remote sends to us. */
86struct keyspan_message {
87	u16	system;
88	u8	button;
89	u8	toggle;
90};
91
92/* Structure used for all the bit testing magic needed to be done. */
93struct bit_tester {
94	u32	tester;
95	int	len;
96	int	pos;
97	int	bits_left;
98	u8	buffer[32];
99};
100
101/* Structure to hold all of our driver specific stuff */
102struct usb_keyspan {
103	char				name[128];
104	char				phys[64];
105	unsigned short			keymap[ARRAY_SIZE(keyspan_key_table)];
106	struct usb_device		*udev;
107	struct input_dev		*input;
108	struct usb_interface		*interface;
109	struct usb_endpoint_descriptor	*in_endpoint;
110	struct urb*			irq_urb;
111	int				open;
112	dma_addr_t			in_dma;
113	unsigned char			*in_buffer;
114
115	/* variables used to parse messages from remote. */
116	struct bit_tester		data;
117	int				stage;
118	int				toggle;
119};
120
121static struct usb_driver keyspan_driver;
122
123/*
124 * Debug routine that prints out what we've received from the remote.
125 */
126static void keyspan_print(struct usb_keyspan* dev) /*unsigned char* data)*/
127{
128	char codes[4 * RECV_SIZE];
129	int i;
130
131	for (i = 0; i < RECV_SIZE; i++)
132		snprintf(codes + i * 3, 4, "%02x ", dev->in_buffer[i]);
133
134	dev_info(&dev->udev->dev, "%s\n", codes);
135}
136
137/*
138 * Routine that manages the bit_tester structure.  It makes sure that there are
139 * at least bits_needed bits loaded into the tester.
140 */
141static int keyspan_load_tester(struct usb_keyspan* dev, int bits_needed)
142{
143	if (dev->data.bits_left >= bits_needed)
144		return 0;
145
146	/*
147	 * Somehow we've missed the last message. The message will be repeated
148	 * though so it's not too big a deal
149	 */
150	if (dev->data.pos >= dev->data.len) {
151		dev_dbg(&dev->interface->dev,
152			"%s - Error ran out of data. pos: %d, len: %d\n",
153			__func__, dev->data.pos, dev->data.len);
154		return -1;
155	}
156
157	/* Load as much as we can into the tester. */
158	while ((dev->data.bits_left + 7 < (sizeof(dev->data.tester) * 8)) &&
159	       (dev->data.pos < dev->data.len)) {
160		dev->data.tester += (dev->data.buffer[dev->data.pos++] << dev->data.bits_left);
161		dev->data.bits_left += 8;
162	}
163
164	return 0;
165}
166
167static void keyspan_report_button(struct usb_keyspan *remote, int button, int press)
168{
169	struct input_dev *input = remote->input;
170
171	input_event(input, EV_MSC, MSC_SCAN, button);
172	input_report_key(input, remote->keymap[button], press);
173	input_sync(input);
174}
175
176/*
177 * Routine that handles all the logic needed to parse out the message from the remote.
178 */
179static 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				dev_err(&remote->interface->dev,
262					"%s - Unknown sequence found in system data.\n",
263					__func__);
264				remote->stage = 0;
265				return;
266			}
267		}
268
269		message.button = 0;
270		for (i = 0; i < 5; i++) {
271			keyspan_load_tester(remote, 6);
272
273			if ((remote->data.tester & ZERO_MASK) == ZERO) {
274				message.button = message.button << 1;
275				remote->data.tester = remote->data.tester >> 5;
276				remote->data.bits_left -= 5;
277			} else if ((remote->data.tester & ONE_MASK) == ONE) {
278				message.button = (message.button << 1) + 1;
279				remote->data.tester = remote->data.tester >> 6;
280				remote->data.bits_left -= 6;
281			} else {
282				dev_err(&remote->interface->dev,
283					"%s - Unknown sequence found in button data.\n",
284					__func__);
285				remote->stage = 0;
286				return;
287			}
288		}
289
290		keyspan_load_tester(remote, 6);
291		if ((remote->data.tester & ZERO_MASK) == ZERO) {
292			message.toggle = 0;
293			remote->data.tester = remote->data.tester >> 5;
294			remote->data.bits_left -= 5;
295		} else if ((remote->data.tester & ONE_MASK) == ONE) {
296			message.toggle = 1;
297			remote->data.tester = remote->data.tester >> 6;
298			remote->data.bits_left -= 6;
299		} else {
300			dev_err(&remote->interface->dev,
301				"%s - Error in message, invalid toggle.\n",
302				__func__);
303			remote->stage = 0;
304			return;
305		}
306
307		keyspan_load_tester(remote, 5);
308		if ((remote->data.tester & STOP_MASK) == STOP) {
309			remote->data.tester = remote->data.tester >> 5;
310			remote->data.bits_left -= 5;
311		} else {
312			dev_err(&remote->interface->dev,
313				"Bad message received, no stop bit found.\n");
314		}
315
316		dev_dbg(&remote->interface->dev,
317			"%s found valid message: system: %d, button: %d, toggle: %d\n",
318			__func__, message.system, message.button, message.toggle);
319
320		if (message.toggle != remote->toggle) {
321			keyspan_report_button(remote, message.button, 1);
322			keyspan_report_button(remote, message.button, 0);
323			remote->toggle = message.toggle;
324		}
325
326		remote->stage = 0;
327		break;
328	}
329}
330
331/*
332 * Routine for sending all the initialization messages to the remote.
333 */
334static int keyspan_setup(struct usb_device* dev)
335{
336	int retval = 0;
337
338	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
339				 0x11, 0x40, 0x5601, 0x0, NULL, 0,
340				 USB_CTRL_SET_TIMEOUT);
341	if (retval) {
342		dev_dbg(&dev->dev, "%s - failed to set bit rate due to error: %d\n",
343			__func__, retval);
344		return(retval);
345	}
346
347	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
348				 0x44, 0x40, 0x0, 0x0, NULL, 0,
349				 USB_CTRL_SET_TIMEOUT);
350	if (retval) {
351		dev_dbg(&dev->dev, "%s - failed to set resume sensitivity due to error: %d\n",
352			__func__, retval);
353		return(retval);
354	}
355
356	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
357				 0x22, 0x40, 0x0, 0x0, NULL, 0,
358				 USB_CTRL_SET_TIMEOUT);
359	if (retval) {
360		dev_dbg(&dev->dev, "%s - failed to turn receive on due to error: %d\n",
361			__func__, retval);
362		return(retval);
363	}
364
365	dev_dbg(&dev->dev, "%s - Setup complete.\n", __func__);
366	return(retval);
367}
368
369/*
370 * Routine used to handle a new message that has come in.
371 */
372static void keyspan_irq_recv(struct urb *urb)
373{
374	struct usb_keyspan *dev = urb->context;
375	int retval;
376
377	/* Check our status in case we need to bail out early. */
378	switch (urb->status) {
379	case 0:
380		break;
381
382	/* Device went away so don't keep trying to read from it. */
383	case -ECONNRESET:
384	case -ENOENT:
385	case -ESHUTDOWN:
386		return;
387
388	default:
389		goto resubmit;
390	}
391
392	if (debug)
393		keyspan_print(dev);
394
395	keyspan_check_data(dev);
396
397resubmit:
398	retval = usb_submit_urb(urb, GFP_ATOMIC);
399	if (retval)
400		dev_err(&dev->interface->dev,
401			"%s - usb_submit_urb failed with result: %d\n",
402			__func__, retval);
403}
404
405static int keyspan_open(struct input_dev *dev)
406{
407	struct usb_keyspan *remote = input_get_drvdata(dev);
408
409	remote->irq_urb->dev = remote->udev;
410	if (usb_submit_urb(remote->irq_urb, GFP_KERNEL))
411		return -EIO;
412
413	return 0;
414}
415
416static void keyspan_close(struct input_dev *dev)
417{
418	struct usb_keyspan *remote = input_get_drvdata(dev);
419
420	usb_kill_urb(remote->irq_urb);
421}
422
423static struct usb_endpoint_descriptor *keyspan_get_in_endpoint(struct usb_host_interface *iface)
424{
425
426	struct usb_endpoint_descriptor *endpoint;
427	int i;
428
429	for (i = 0; i < iface->desc.bNumEndpoints; ++i) {
430		endpoint = &iface->endpoint[i].desc;
431
432		if (usb_endpoint_is_int_in(endpoint)) {
433			/* we found our interrupt in endpoint */
434			return endpoint;
435		}
436	}
437
438	return NULL;
439}
440
441/*
442 * Routine that sets up the driver to handle a specific USB device detected on the bus.
443 */
444static int keyspan_probe(struct usb_interface *interface, const struct usb_device_id *id)
445{
446	struct usb_device *udev = interface_to_usbdev(interface);
447	struct usb_endpoint_descriptor *endpoint;
448	struct usb_keyspan *remote;
449	struct input_dev *input_dev;
450	int i, error;
451
452	endpoint = keyspan_get_in_endpoint(interface->cur_altsetting);
453	if (!endpoint)
454		return -ENODEV;
455
456	remote = kzalloc(sizeof(*remote), GFP_KERNEL);
457	input_dev = input_allocate_device();
458	if (!remote || !input_dev) {
459		error = -ENOMEM;
460		goto fail1;
461	}
462
463	remote->udev = udev;
464	remote->input = input_dev;
465	remote->interface = interface;
466	remote->in_endpoint = endpoint;
467	remote->toggle = -1;	/* Set to -1 so we will always not match the toggle from the first remote message. */
468
469	remote->in_buffer = usb_alloc_coherent(udev, RECV_SIZE, GFP_KERNEL, &remote->in_dma);
470	if (!remote->in_buffer) {
471		error = -ENOMEM;
472		goto fail1;
473	}
474
475	remote->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
476	if (!remote->irq_urb) {
477		error = -ENOMEM;
478		goto fail2;
479	}
480
481	error = keyspan_setup(udev);
482	if (error) {
483		error = -ENODEV;
484		goto fail3;
485	}
486
487	if (udev->manufacturer)
488		strscpy(remote->name, udev->manufacturer, sizeof(remote->name));
489
490	if (udev->product) {
491		if (udev->manufacturer)
492			strlcat(remote->name, " ", sizeof(remote->name));
493		strlcat(remote->name, udev->product, sizeof(remote->name));
494	}
495
496	if (!strlen(remote->name))
497		snprintf(remote->name, sizeof(remote->name),
498			 "USB Keyspan Remote %04x:%04x",
499			 le16_to_cpu(udev->descriptor.idVendor),
500			 le16_to_cpu(udev->descriptor.idProduct));
501
502	usb_make_path(udev, remote->phys, sizeof(remote->phys));
503	strlcat(remote->phys, "/input0", sizeof(remote->phys));
504	memcpy(remote->keymap, keyspan_key_table, sizeof(remote->keymap));
505
506	input_dev->name = remote->name;
507	input_dev->phys = remote->phys;
508	usb_to_input_id(udev, &input_dev->id);
509	input_dev->dev.parent = &interface->dev;
510	input_dev->keycode = remote->keymap;
511	input_dev->keycodesize = sizeof(unsigned short);
512	input_dev->keycodemax = ARRAY_SIZE(remote->keymap);
513
514	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
515	__set_bit(EV_KEY, input_dev->evbit);
516	for (i = 0; i < ARRAY_SIZE(keyspan_key_table); i++)
517		__set_bit(keyspan_key_table[i], input_dev->keybit);
518	__clear_bit(KEY_RESERVED, input_dev->keybit);
519
520	input_set_drvdata(input_dev, remote);
521
522	input_dev->open = keyspan_open;
523	input_dev->close = keyspan_close;
524
525	/*
526	 * Initialize the URB to access the device.
527	 * The urb gets sent to the device in keyspan_open()
528	 */
529	usb_fill_int_urb(remote->irq_urb,
530			 remote->udev,
531			 usb_rcvintpipe(remote->udev, endpoint->bEndpointAddress),
532			 remote->in_buffer, RECV_SIZE, keyspan_irq_recv, remote,
533			 endpoint->bInterval);
534	remote->irq_urb->transfer_dma = remote->in_dma;
535	remote->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
536
537	/* we can register the device now, as it is ready */
538	error = input_register_device(remote->input);
539	if (error)
540		goto fail3;
541
542	/* save our data pointer in this interface device */
543	usb_set_intfdata(interface, remote);
544
545	return 0;
546
547 fail3:	usb_free_urb(remote->irq_urb);
548 fail2:	usb_free_coherent(udev, RECV_SIZE, remote->in_buffer, remote->in_dma);
549 fail1:	kfree(remote);
550	input_free_device(input_dev);
551
552	return error;
553}
554
555/*
556 * Routine called when a device is disconnected from the USB.
557 */
558static void keyspan_disconnect(struct usb_interface *interface)
559{
560	struct usb_keyspan *remote;
561
562	remote = usb_get_intfdata(interface);
563	usb_set_intfdata(interface, NULL);
564
565	if (remote) {	/* We have a valid driver structure so clean up everything we allocated. */
566		input_unregister_device(remote->input);
567		usb_kill_urb(remote->irq_urb);
568		usb_free_urb(remote->irq_urb);
569		usb_free_coherent(remote->udev, RECV_SIZE, remote->in_buffer, remote->in_dma);
570		kfree(remote);
571	}
572}
573
574/*
575 * Standard driver set up sections
576 */
577static struct usb_driver keyspan_driver =
578{
579	.name =		"keyspan_remote",
580	.probe =	keyspan_probe,
581	.disconnect =	keyspan_disconnect,
582	.id_table =	keyspan_table
583};
584
585module_usb_driver(keyspan_driver);
586
587MODULE_DEVICE_TABLE(usb, keyspan_table);
588MODULE_AUTHOR("Michael Downey <downey@zymeta.com>");
589MODULE_DESCRIPTION("Driver for the USB Keyspan remote control.");
590MODULE_LICENSE("GPL");
591