1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Streamzap Remote Control driver
4 *
5 * Copyright (c) 2005 Christoph Bartelmus <lirc@bartelmus.de>
6 * Copyright (c) 2010 Jarod Wilson <jarod@wilsonet.com>
7 *
8 * This driver was based on the work of Greg Wickham and Adrian
9 * Dewhurst. It was substantially rewritten to support correct signal
10 * gaps and now maintains a delay buffer, which is used to present
11 * consistent timing behaviour to user space applications. Without the
12 * delay buffer an ugly hack would be required in lircd, which can
13 * cause sluggish signal decoding in certain situations.
14 *
15 * Ported to in-kernel ir-core interface by Jarod Wilson
16 *
17 * This driver is based on the USB skeleton driver packaged with the
18 * kernel; copyright (C) 2001-2003 Greg Kroah-Hartman (greg@kroah.com)
19 */
20
21#include <linux/device.h>
22#include <linux/module.h>
23#include <linux/slab.h>
24#include <linux/ktime.h>
25#include <linux/usb.h>
26#include <linux/usb/input.h>
27#include <media/rc-core.h>
28
29#define DRIVER_VERSION	"1.61"
30#define DRIVER_NAME	"streamzap"
31#define DRIVER_DESC	"Streamzap Remote Control driver"
32
33#define USB_STREAMZAP_VENDOR_ID		0x0e9c
34#define USB_STREAMZAP_PRODUCT_ID	0x0000
35
36/* table of devices that work with this driver */
37static const struct usb_device_id streamzap_table[] = {
38	/* Streamzap Remote Control */
39	{ USB_DEVICE(USB_STREAMZAP_VENDOR_ID, USB_STREAMZAP_PRODUCT_ID) },
40	/* Terminating entry */
41	{ }
42};
43
44MODULE_DEVICE_TABLE(usb, streamzap_table);
45
46#define SZ_PULSE_MASK 0xf0
47#define SZ_SPACE_MASK 0x0f
48#define SZ_TIMEOUT    0xff
49#define SZ_RESOLUTION 256
50
51/* number of samples buffered */
52#define SZ_BUF_LEN 128
53
54enum StreamzapDecoderState {
55	PulseSpace,
56	FullPulse,
57	FullSpace,
58	IgnorePulse
59};
60
61/* structure to hold our device specific stuff */
62struct streamzap_ir {
63	/* ir-core */
64	struct rc_dev *rdev;
65
66	/* core device info */
67	struct device *dev;
68
69	/* usb */
70	struct usb_device	*usbdev;
71	struct usb_interface	*interface;
72	struct usb_endpoint_descriptor *endpoint;
73	struct urb		*urb_in;
74
75	/* buffer & dma */
76	unsigned char		*buf_in;
77	dma_addr_t		dma_in;
78	unsigned int		buf_in_len;
79
80	/* track what state we're in */
81	enum StreamzapDecoderState decoder_state;
82	/* tracks whether we are currently receiving some signal */
83	bool			idle;
84	/* sum of signal lengths received since signal start */
85	unsigned long		sum;
86	/* start time of signal; necessary for gap tracking */
87	ktime_t			signal_last;
88	ktime_t			signal_start;
89	bool			timeout_enabled;
90
91	char			name[128];
92	char			phys[64];
93};
94
95
96/* local function prototypes */
97static int streamzap_probe(struct usb_interface *interface,
98			   const struct usb_device_id *id);
99static void streamzap_disconnect(struct usb_interface *interface);
100static void streamzap_callback(struct urb *urb);
101static int streamzap_suspend(struct usb_interface *intf, pm_message_t message);
102static int streamzap_resume(struct usb_interface *intf);
103
104/* usb specific object needed to register this driver with the usb subsystem */
105static struct usb_driver streamzap_driver = {
106	.name =		DRIVER_NAME,
107	.probe =	streamzap_probe,
108	.disconnect =	streamzap_disconnect,
109	.suspend =	streamzap_suspend,
110	.resume =	streamzap_resume,
111	.id_table =	streamzap_table,
112};
113
114static void sz_push(struct streamzap_ir *sz, struct ir_raw_event rawir)
115{
116	dev_dbg(sz->dev, "Storing %s with duration %u us\n",
117		(rawir.pulse ? "pulse" : "space"), rawir.duration);
118	ir_raw_event_store_with_filter(sz->rdev, &rawir);
119}
120
121static void sz_push_full_pulse(struct streamzap_ir *sz,
122			       unsigned char value)
123{
124	struct ir_raw_event rawir = {};
125
126	if (sz->idle) {
127		int delta;
128
129		sz->signal_last = sz->signal_start;
130		sz->signal_start = ktime_get_real();
131
132		delta = ktime_us_delta(sz->signal_start, sz->signal_last);
133		rawir.pulse = false;
134		if (delta > (15 * USEC_PER_SEC)) {
135			/* really long time */
136			rawir.duration = IR_MAX_DURATION;
137		} else {
138			rawir.duration = delta;
139			rawir.duration -= sz->sum;
140			rawir.duration = (rawir.duration > IR_MAX_DURATION) ?
141					 IR_MAX_DURATION : rawir.duration;
142		}
143		sz_push(sz, rawir);
144
145		sz->idle = false;
146		sz->sum = 0;
147	}
148
149	rawir.pulse = true;
150	rawir.duration = ((int) value) * SZ_RESOLUTION;
151	rawir.duration += SZ_RESOLUTION / 2;
152	sz->sum += rawir.duration;
153	rawir.duration = (rawir.duration > IR_MAX_DURATION) ?
154			 IR_MAX_DURATION : rawir.duration;
155	sz_push(sz, rawir);
156}
157
158static void sz_push_half_pulse(struct streamzap_ir *sz,
159			       unsigned char value)
160{
161	sz_push_full_pulse(sz, (value & SZ_PULSE_MASK) >> 4);
162}
163
164static void sz_push_full_space(struct streamzap_ir *sz,
165			       unsigned char value)
166{
167	struct ir_raw_event rawir = {};
168
169	rawir.pulse = false;
170	rawir.duration = ((int) value) * SZ_RESOLUTION;
171	rawir.duration += SZ_RESOLUTION / 2;
172	sz->sum += rawir.duration;
173	sz_push(sz, rawir);
174}
175
176static void sz_push_half_space(struct streamzap_ir *sz,
177			       unsigned long value)
178{
179	sz_push_full_space(sz, value & SZ_SPACE_MASK);
180}
181
182/*
183 * streamzap_callback - usb IRQ handler callback
184 *
185 * This procedure is invoked on reception of data from
186 * the usb remote.
187 */
188static void streamzap_callback(struct urb *urb)
189{
190	struct streamzap_ir *sz;
191	unsigned int i;
192	int len;
193
194	if (!urb)
195		return;
196
197	sz = urb->context;
198	len = urb->actual_length;
199
200	switch (urb->status) {
201	case -ECONNRESET:
202	case -ENOENT:
203	case -ESHUTDOWN:
204		/*
205		 * this urb is terminated, clean up.
206		 * sz might already be invalid at this point
207		 */
208		dev_err(sz->dev, "urb terminated, status: %d\n", urb->status);
209		return;
210	default:
211		break;
212	}
213
214	dev_dbg(sz->dev, "%s: received urb, len %d\n", __func__, len);
215	for (i = 0; i < len; i++) {
216		dev_dbg(sz->dev, "sz->buf_in[%d]: %x\n",
217			i, (unsigned char)sz->buf_in[i]);
218		switch (sz->decoder_state) {
219		case PulseSpace:
220			if ((sz->buf_in[i] & SZ_PULSE_MASK) ==
221				SZ_PULSE_MASK) {
222				sz->decoder_state = FullPulse;
223				continue;
224			} else if ((sz->buf_in[i] & SZ_SPACE_MASK)
225					== SZ_SPACE_MASK) {
226				sz_push_half_pulse(sz, sz->buf_in[i]);
227				sz->decoder_state = FullSpace;
228				continue;
229			} else {
230				sz_push_half_pulse(sz, sz->buf_in[i]);
231				sz_push_half_space(sz, sz->buf_in[i]);
232			}
233			break;
234		case FullPulse:
235			sz_push_full_pulse(sz, sz->buf_in[i]);
236			sz->decoder_state = IgnorePulse;
237			break;
238		case FullSpace:
239			if (sz->buf_in[i] == SZ_TIMEOUT) {
240				struct ir_raw_event rawir = {
241					.pulse = false,
242					.duration = sz->rdev->timeout
243				};
244				sz->idle = true;
245				if (sz->timeout_enabled)
246					sz_push(sz, rawir);
247				ir_raw_event_handle(sz->rdev);
248				ir_raw_event_reset(sz->rdev);
249			} else {
250				sz_push_full_space(sz, sz->buf_in[i]);
251			}
252			sz->decoder_state = PulseSpace;
253			break;
254		case IgnorePulse:
255			if ((sz->buf_in[i] & SZ_SPACE_MASK) ==
256				SZ_SPACE_MASK) {
257				sz->decoder_state = FullSpace;
258				continue;
259			}
260			sz_push_half_space(sz, sz->buf_in[i]);
261			sz->decoder_state = PulseSpace;
262			break;
263		}
264	}
265
266	ir_raw_event_handle(sz->rdev);
267	usb_submit_urb(urb, GFP_ATOMIC);
268
269	return;
270}
271
272static struct rc_dev *streamzap_init_rc_dev(struct streamzap_ir *sz)
273{
274	struct rc_dev *rdev;
275	struct device *dev = sz->dev;
276	int ret;
277
278	rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
279	if (!rdev) {
280		dev_err(dev, "remote dev allocation failed\n");
281		goto out;
282	}
283
284	snprintf(sz->name, sizeof(sz->name), "Streamzap PC Remote Infrared Receiver (%04x:%04x)",
285		 le16_to_cpu(sz->usbdev->descriptor.idVendor),
286		 le16_to_cpu(sz->usbdev->descriptor.idProduct));
287	usb_make_path(sz->usbdev, sz->phys, sizeof(sz->phys));
288	strlcat(sz->phys, "/input0", sizeof(sz->phys));
289
290	rdev->device_name = sz->name;
291	rdev->input_phys = sz->phys;
292	usb_to_input_id(sz->usbdev, &rdev->input_id);
293	rdev->dev.parent = dev;
294	rdev->priv = sz;
295	rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
296	rdev->driver_name = DRIVER_NAME;
297	rdev->map_name = RC_MAP_STREAMZAP;
298
299	ret = rc_register_device(rdev);
300	if (ret < 0) {
301		dev_err(dev, "remote input device register failed\n");
302		goto out;
303	}
304
305	return rdev;
306
307out:
308	rc_free_device(rdev);
309	return NULL;
310}
311
312/*
313 *	streamzap_probe
314 *
315 *	Called by usb-core to associated with a candidate device
316 *	On any failure the return value is the ERROR
317 *	On success return 0
318 */
319static int streamzap_probe(struct usb_interface *intf,
320			   const struct usb_device_id *id)
321{
322	struct usb_device *usbdev = interface_to_usbdev(intf);
323	struct usb_host_interface *iface_host;
324	struct streamzap_ir *sz = NULL;
325	char buf[63], name[128] = "";
326	int retval = -ENOMEM;
327	int pipe, maxp;
328
329	/* Allocate space for device driver specific data */
330	sz = kzalloc(sizeof(struct streamzap_ir), GFP_KERNEL);
331	if (!sz)
332		return -ENOMEM;
333
334	sz->usbdev = usbdev;
335	sz->interface = intf;
336
337	/* Check to ensure endpoint information matches requirements */
338	iface_host = intf->cur_altsetting;
339
340	if (iface_host->desc.bNumEndpoints != 1) {
341		dev_err(&intf->dev, "%s: Unexpected desc.bNumEndpoints (%d)\n",
342			__func__, iface_host->desc.bNumEndpoints);
343		retval = -ENODEV;
344		goto free_sz;
345	}
346
347	sz->endpoint = &(iface_host->endpoint[0].desc);
348	if (!usb_endpoint_dir_in(sz->endpoint)) {
349		dev_err(&intf->dev, "%s: endpoint doesn't match input device 02%02x\n",
350			__func__, sz->endpoint->bEndpointAddress);
351		retval = -ENODEV;
352		goto free_sz;
353	}
354
355	if (!usb_endpoint_xfer_int(sz->endpoint)) {
356		dev_err(&intf->dev, "%s: endpoint attributes don't match xfer 02%02x\n",
357			__func__, sz->endpoint->bmAttributes);
358		retval = -ENODEV;
359		goto free_sz;
360	}
361
362	pipe = usb_rcvintpipe(usbdev, sz->endpoint->bEndpointAddress);
363	maxp = usb_maxpacket(usbdev, pipe, usb_pipeout(pipe));
364
365	if (maxp == 0) {
366		dev_err(&intf->dev, "%s: endpoint Max Packet Size is 0!?!\n",
367			__func__);
368		retval = -ENODEV;
369		goto free_sz;
370	}
371
372	/* Allocate the USB buffer and IRQ URB */
373	sz->buf_in = usb_alloc_coherent(usbdev, maxp, GFP_ATOMIC, &sz->dma_in);
374	if (!sz->buf_in)
375		goto free_sz;
376
377	sz->urb_in = usb_alloc_urb(0, GFP_KERNEL);
378	if (!sz->urb_in)
379		goto free_buf_in;
380
381	sz->dev = &intf->dev;
382	sz->buf_in_len = maxp;
383
384	if (usbdev->descriptor.iManufacturer
385	    && usb_string(usbdev, usbdev->descriptor.iManufacturer,
386			  buf, sizeof(buf)) > 0)
387		strscpy(name, buf, sizeof(name));
388
389	if (usbdev->descriptor.iProduct
390	    && usb_string(usbdev, usbdev->descriptor.iProduct,
391			  buf, sizeof(buf)) > 0)
392		snprintf(name + strlen(name), sizeof(name) - strlen(name),
393			 " %s", buf);
394
395	sz->rdev = streamzap_init_rc_dev(sz);
396	if (!sz->rdev)
397		goto rc_dev_fail;
398
399	sz->idle = true;
400	sz->decoder_state = PulseSpace;
401	/* FIXME: don't yet have a way to set this */
402	sz->timeout_enabled = true;
403	sz->rdev->timeout = SZ_TIMEOUT * SZ_RESOLUTION;
404	#if 0
405	/* not yet supported, depends on patches from maxim */
406	/* see also: LIRC_GET_REC_RESOLUTION and LIRC_SET_REC_TIMEOUT */
407	sz->min_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
408	sz->max_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
409	#endif
410
411	sz->signal_start = ktime_get_real();
412
413	/* Complete final initialisations */
414	usb_fill_int_urb(sz->urb_in, usbdev, pipe, sz->buf_in,
415			 maxp, (usb_complete_t)streamzap_callback,
416			 sz, sz->endpoint->bInterval);
417	sz->urb_in->transfer_dma = sz->dma_in;
418	sz->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
419
420	usb_set_intfdata(intf, sz);
421
422	if (usb_submit_urb(sz->urb_in, GFP_ATOMIC))
423		dev_err(sz->dev, "urb submit failed\n");
424
425	dev_info(sz->dev, "Registered %s on usb%d:%d\n", name,
426		 usbdev->bus->busnum, usbdev->devnum);
427
428	return 0;
429
430rc_dev_fail:
431	usb_free_urb(sz->urb_in);
432free_buf_in:
433	usb_free_coherent(usbdev, maxp, sz->buf_in, sz->dma_in);
434free_sz:
435	kfree(sz);
436
437	return retval;
438}
439
440/*
441 * streamzap_disconnect
442 *
443 * Called by the usb core when the device is removed from the system.
444 *
445 * This routine guarantees that the driver will not submit any more urbs
446 * by clearing dev->usbdev.  It is also supposed to terminate any currently
447 * active urbs.  Unfortunately, usb_bulk_msg(), used in streamzap_read(),
448 * does not provide any way to do this.
449 */
450static void streamzap_disconnect(struct usb_interface *interface)
451{
452	struct streamzap_ir *sz = usb_get_intfdata(interface);
453	struct usb_device *usbdev = interface_to_usbdev(interface);
454
455	usb_set_intfdata(interface, NULL);
456
457	if (!sz)
458		return;
459
460	sz->usbdev = NULL;
461	rc_unregister_device(sz->rdev);
462	usb_kill_urb(sz->urb_in);
463	usb_free_urb(sz->urb_in);
464	usb_free_coherent(usbdev, sz->buf_in_len, sz->buf_in, sz->dma_in);
465
466	kfree(sz);
467}
468
469static int streamzap_suspend(struct usb_interface *intf, pm_message_t message)
470{
471	struct streamzap_ir *sz = usb_get_intfdata(intf);
472
473	usb_kill_urb(sz->urb_in);
474
475	return 0;
476}
477
478static int streamzap_resume(struct usb_interface *intf)
479{
480	struct streamzap_ir *sz = usb_get_intfdata(intf);
481
482	if (usb_submit_urb(sz->urb_in, GFP_ATOMIC)) {
483		dev_err(sz->dev, "Error submitting urb\n");
484		return -EIO;
485	}
486
487	return 0;
488}
489
490module_usb_driver(streamzap_driver);
491
492MODULE_AUTHOR("Jarod Wilson <jarod@wilsonet.com>");
493MODULE_DESCRIPTION(DRIVER_DESC);
494MODULE_LICENSE("GPL");
495