xref: /linux/drivers/media/rc/streamzap.c (revision b8d312aa075f33282565467662c4628dae0a2aff)
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 */
37 static 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 
44 MODULE_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 
54 enum StreamzapDecoderState {
55 	PulseSpace,
56 	FullPulse,
57 	FullSpace,
58 	IgnorePulse
59 };
60 
61 /* structure to hold our device specific stuff */
62 struct 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 */
97 static int streamzap_probe(struct usb_interface *interface,
98 			   const struct usb_device_id *id);
99 static void streamzap_disconnect(struct usb_interface *interface);
100 static void streamzap_callback(struct urb *urb);
101 static int streamzap_suspend(struct usb_interface *intf, pm_message_t message);
102 static int streamzap_resume(struct usb_interface *intf);
103 
104 /* usb specific object needed to register this driver with the usb subsystem */
105 static 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 
114 static 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 
121 static 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 = US_TO_NS(rawir.duration);
141 			rawir.duration = (rawir.duration > IR_MAX_DURATION) ?
142 					 IR_MAX_DURATION : rawir.duration;
143 		}
144 		sz_push(sz, rawir);
145 
146 		sz->idle = false;
147 		sz->sum = 0;
148 	}
149 
150 	rawir.pulse = true;
151 	rawir.duration = ((int) value) * SZ_RESOLUTION;
152 	rawir.duration += SZ_RESOLUTION / 2;
153 	sz->sum += rawir.duration;
154 	rawir.duration = US_TO_NS(rawir.duration);
155 	rawir.duration = (rawir.duration > IR_MAX_DURATION) ?
156 			 IR_MAX_DURATION : rawir.duration;
157 	sz_push(sz, rawir);
158 }
159 
160 static void sz_push_half_pulse(struct streamzap_ir *sz,
161 			       unsigned char value)
162 {
163 	sz_push_full_pulse(sz, (value & SZ_PULSE_MASK) >> 4);
164 }
165 
166 static void sz_push_full_space(struct streamzap_ir *sz,
167 			       unsigned char value)
168 {
169 	struct ir_raw_event rawir = {};
170 
171 	rawir.pulse = false;
172 	rawir.duration = ((int) value) * SZ_RESOLUTION;
173 	rawir.duration += SZ_RESOLUTION / 2;
174 	sz->sum += rawir.duration;
175 	rawir.duration = US_TO_NS(rawir.duration);
176 	sz_push(sz, rawir);
177 }
178 
179 static void sz_push_half_space(struct streamzap_ir *sz,
180 			       unsigned long value)
181 {
182 	sz_push_full_space(sz, value & SZ_SPACE_MASK);
183 }
184 
185 /*
186  * streamzap_callback - usb IRQ handler callback
187  *
188  * This procedure is invoked on reception of data from
189  * the usb remote.
190  */
191 static void streamzap_callback(struct urb *urb)
192 {
193 	struct streamzap_ir *sz;
194 	unsigned int i;
195 	int len;
196 
197 	if (!urb)
198 		return;
199 
200 	sz = urb->context;
201 	len = urb->actual_length;
202 
203 	switch (urb->status) {
204 	case -ECONNRESET:
205 	case -ENOENT:
206 	case -ESHUTDOWN:
207 		/*
208 		 * this urb is terminated, clean up.
209 		 * sz might already be invalid at this point
210 		 */
211 		dev_err(sz->dev, "urb terminated, status: %d\n", urb->status);
212 		return;
213 	default:
214 		break;
215 	}
216 
217 	dev_dbg(sz->dev, "%s: received urb, len %d\n", __func__, len);
218 	for (i = 0; i < len; i++) {
219 		dev_dbg(sz->dev, "sz->buf_in[%d]: %x\n",
220 			i, (unsigned char)sz->buf_in[i]);
221 		switch (sz->decoder_state) {
222 		case PulseSpace:
223 			if ((sz->buf_in[i] & SZ_PULSE_MASK) ==
224 				SZ_PULSE_MASK) {
225 				sz->decoder_state = FullPulse;
226 				continue;
227 			} else if ((sz->buf_in[i] & SZ_SPACE_MASK)
228 					== SZ_SPACE_MASK) {
229 				sz_push_half_pulse(sz, sz->buf_in[i]);
230 				sz->decoder_state = FullSpace;
231 				continue;
232 			} else {
233 				sz_push_half_pulse(sz, sz->buf_in[i]);
234 				sz_push_half_space(sz, sz->buf_in[i]);
235 			}
236 			break;
237 		case FullPulse:
238 			sz_push_full_pulse(sz, sz->buf_in[i]);
239 			sz->decoder_state = IgnorePulse;
240 			break;
241 		case FullSpace:
242 			if (sz->buf_in[i] == SZ_TIMEOUT) {
243 				struct ir_raw_event rawir = {
244 					.pulse = false,
245 					.duration = sz->rdev->timeout
246 				};
247 				sz->idle = true;
248 				if (sz->timeout_enabled)
249 					sz_push(sz, rawir);
250 				ir_raw_event_handle(sz->rdev);
251 				ir_raw_event_reset(sz->rdev);
252 			} else {
253 				sz_push_full_space(sz, sz->buf_in[i]);
254 			}
255 			sz->decoder_state = PulseSpace;
256 			break;
257 		case IgnorePulse:
258 			if ((sz->buf_in[i] & SZ_SPACE_MASK) ==
259 				SZ_SPACE_MASK) {
260 				sz->decoder_state = FullSpace;
261 				continue;
262 			}
263 			sz_push_half_space(sz, sz->buf_in[i]);
264 			sz->decoder_state = PulseSpace;
265 			break;
266 		}
267 	}
268 
269 	ir_raw_event_handle(sz->rdev);
270 	usb_submit_urb(urb, GFP_ATOMIC);
271 
272 	return;
273 }
274 
275 static struct rc_dev *streamzap_init_rc_dev(struct streamzap_ir *sz)
276 {
277 	struct rc_dev *rdev;
278 	struct device *dev = sz->dev;
279 	int ret;
280 
281 	rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
282 	if (!rdev) {
283 		dev_err(dev, "remote dev allocation failed\n");
284 		goto out;
285 	}
286 
287 	snprintf(sz->name, sizeof(sz->name), "Streamzap PC Remote Infrared Receiver (%04x:%04x)",
288 		 le16_to_cpu(sz->usbdev->descriptor.idVendor),
289 		 le16_to_cpu(sz->usbdev->descriptor.idProduct));
290 	usb_make_path(sz->usbdev, sz->phys, sizeof(sz->phys));
291 	strlcat(sz->phys, "/input0", sizeof(sz->phys));
292 
293 	rdev->device_name = sz->name;
294 	rdev->input_phys = sz->phys;
295 	usb_to_input_id(sz->usbdev, &rdev->input_id);
296 	rdev->dev.parent = dev;
297 	rdev->priv = sz;
298 	rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
299 	rdev->driver_name = DRIVER_NAME;
300 	rdev->map_name = RC_MAP_STREAMZAP;
301 
302 	ret = rc_register_device(rdev);
303 	if (ret < 0) {
304 		dev_err(dev, "remote input device register failed\n");
305 		goto out;
306 	}
307 
308 	return rdev;
309 
310 out:
311 	rc_free_device(rdev);
312 	return NULL;
313 }
314 
315 /*
316  *	streamzap_probe
317  *
318  *	Called by usb-core to associated with a candidate device
319  *	On any failure the return value is the ERROR
320  *	On success return 0
321  */
322 static int streamzap_probe(struct usb_interface *intf,
323 			   const struct usb_device_id *id)
324 {
325 	struct usb_device *usbdev = interface_to_usbdev(intf);
326 	struct usb_host_interface *iface_host;
327 	struct streamzap_ir *sz = NULL;
328 	char buf[63], name[128] = "";
329 	int retval = -ENOMEM;
330 	int pipe, maxp;
331 
332 	/* Allocate space for device driver specific data */
333 	sz = kzalloc(sizeof(struct streamzap_ir), GFP_KERNEL);
334 	if (!sz)
335 		return -ENOMEM;
336 
337 	sz->usbdev = usbdev;
338 	sz->interface = intf;
339 
340 	/* Check to ensure endpoint information matches requirements */
341 	iface_host = intf->cur_altsetting;
342 
343 	if (iface_host->desc.bNumEndpoints != 1) {
344 		dev_err(&intf->dev, "%s: Unexpected desc.bNumEndpoints (%d)\n",
345 			__func__, iface_host->desc.bNumEndpoints);
346 		retval = -ENODEV;
347 		goto free_sz;
348 	}
349 
350 	sz->endpoint = &(iface_host->endpoint[0].desc);
351 	if (!usb_endpoint_dir_in(sz->endpoint)) {
352 		dev_err(&intf->dev, "%s: endpoint doesn't match input device 02%02x\n",
353 			__func__, sz->endpoint->bEndpointAddress);
354 		retval = -ENODEV;
355 		goto free_sz;
356 	}
357 
358 	if (!usb_endpoint_xfer_int(sz->endpoint)) {
359 		dev_err(&intf->dev, "%s: endpoint attributes don't match xfer 02%02x\n",
360 			__func__, sz->endpoint->bmAttributes);
361 		retval = -ENODEV;
362 		goto free_sz;
363 	}
364 
365 	pipe = usb_rcvintpipe(usbdev, sz->endpoint->bEndpointAddress);
366 	maxp = usb_maxpacket(usbdev, pipe, usb_pipeout(pipe));
367 
368 	if (maxp == 0) {
369 		dev_err(&intf->dev, "%s: endpoint Max Packet Size is 0!?!\n",
370 			__func__);
371 		retval = -ENODEV;
372 		goto free_sz;
373 	}
374 
375 	/* Allocate the USB buffer and IRQ URB */
376 	sz->buf_in = usb_alloc_coherent(usbdev, maxp, GFP_ATOMIC, &sz->dma_in);
377 	if (!sz->buf_in)
378 		goto free_sz;
379 
380 	sz->urb_in = usb_alloc_urb(0, GFP_KERNEL);
381 	if (!sz->urb_in)
382 		goto free_buf_in;
383 
384 	sz->dev = &intf->dev;
385 	sz->buf_in_len = maxp;
386 
387 	if (usbdev->descriptor.iManufacturer
388 	    && usb_string(usbdev, usbdev->descriptor.iManufacturer,
389 			  buf, sizeof(buf)) > 0)
390 		strscpy(name, buf, sizeof(name));
391 
392 	if (usbdev->descriptor.iProduct
393 	    && usb_string(usbdev, usbdev->descriptor.iProduct,
394 			  buf, sizeof(buf)) > 0)
395 		snprintf(name + strlen(name), sizeof(name) - strlen(name),
396 			 " %s", buf);
397 
398 	sz->rdev = streamzap_init_rc_dev(sz);
399 	if (!sz->rdev)
400 		goto rc_dev_fail;
401 
402 	sz->idle = true;
403 	sz->decoder_state = PulseSpace;
404 	/* FIXME: don't yet have a way to set this */
405 	sz->timeout_enabled = true;
406 	sz->rdev->timeout = ((US_TO_NS(SZ_TIMEOUT * SZ_RESOLUTION) &
407 				IR_MAX_DURATION) | 0x03000000);
408 	#if 0
409 	/* not yet supported, depends on patches from maxim */
410 	/* see also: LIRC_GET_REC_RESOLUTION and LIRC_SET_REC_TIMEOUT */
411 	sz->min_timeout = US_TO_NS(SZ_TIMEOUT * SZ_RESOLUTION);
412 	sz->max_timeout = US_TO_NS(SZ_TIMEOUT * SZ_RESOLUTION);
413 	#endif
414 
415 	sz->signal_start = ktime_get_real();
416 
417 	/* Complete final initialisations */
418 	usb_fill_int_urb(sz->urb_in, usbdev, pipe, sz->buf_in,
419 			 maxp, (usb_complete_t)streamzap_callback,
420 			 sz, sz->endpoint->bInterval);
421 	sz->urb_in->transfer_dma = sz->dma_in;
422 	sz->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
423 
424 	usb_set_intfdata(intf, sz);
425 
426 	if (usb_submit_urb(sz->urb_in, GFP_ATOMIC))
427 		dev_err(sz->dev, "urb submit failed\n");
428 
429 	dev_info(sz->dev, "Registered %s on usb%d:%d\n", name,
430 		 usbdev->bus->busnum, usbdev->devnum);
431 
432 	return 0;
433 
434 rc_dev_fail:
435 	usb_free_urb(sz->urb_in);
436 free_buf_in:
437 	usb_free_coherent(usbdev, maxp, sz->buf_in, sz->dma_in);
438 free_sz:
439 	kfree(sz);
440 
441 	return retval;
442 }
443 
444 /*
445  * streamzap_disconnect
446  *
447  * Called by the usb core when the device is removed from the system.
448  *
449  * This routine guarantees that the driver will not submit any more urbs
450  * by clearing dev->usbdev.  It is also supposed to terminate any currently
451  * active urbs.  Unfortunately, usb_bulk_msg(), used in streamzap_read(),
452  * does not provide any way to do this.
453  */
454 static void streamzap_disconnect(struct usb_interface *interface)
455 {
456 	struct streamzap_ir *sz = usb_get_intfdata(interface);
457 	struct usb_device *usbdev = interface_to_usbdev(interface);
458 
459 	usb_set_intfdata(interface, NULL);
460 
461 	if (!sz)
462 		return;
463 
464 	sz->usbdev = NULL;
465 	rc_unregister_device(sz->rdev);
466 	usb_kill_urb(sz->urb_in);
467 	usb_free_urb(sz->urb_in);
468 	usb_free_coherent(usbdev, sz->buf_in_len, sz->buf_in, sz->dma_in);
469 
470 	kfree(sz);
471 }
472 
473 static int streamzap_suspend(struct usb_interface *intf, pm_message_t message)
474 {
475 	struct streamzap_ir *sz = usb_get_intfdata(intf);
476 
477 	usb_kill_urb(sz->urb_in);
478 
479 	return 0;
480 }
481 
482 static int streamzap_resume(struct usb_interface *intf)
483 {
484 	struct streamzap_ir *sz = usb_get_intfdata(intf);
485 
486 	if (usb_submit_urb(sz->urb_in, GFP_ATOMIC)) {
487 		dev_err(sz->dev, "Error submitting urb\n");
488 		return -EIO;
489 	}
490 
491 	return 0;
492 }
493 
494 module_usb_driver(streamzap_driver);
495 
496 MODULE_AUTHOR("Jarod Wilson <jarod@wilsonet.com>");
497 MODULE_DESCRIPTION(DRIVER_DESC);
498 MODULE_LICENSE("GPL");
499