xref: /openbmc/linux/drivers/media/rc/streamzap.c (revision 48cc39c3)
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 = (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 
158 static 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 
164 static 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 
176 static 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  */
188 static 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 
270 static struct rc_dev *streamzap_init_rc_dev(struct streamzap_ir *sz)
271 {
272 	struct rc_dev *rdev;
273 	struct device *dev = sz->dev;
274 	int ret;
275 
276 	rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
277 	if (!rdev) {
278 		dev_err(dev, "remote dev allocation failed\n");
279 		goto out;
280 	}
281 
282 	snprintf(sz->name, sizeof(sz->name), "Streamzap PC Remote Infrared Receiver (%04x:%04x)",
283 		 le16_to_cpu(sz->usbdev->descriptor.idVendor),
284 		 le16_to_cpu(sz->usbdev->descriptor.idProduct));
285 	usb_make_path(sz->usbdev, sz->phys, sizeof(sz->phys));
286 	strlcat(sz->phys, "/input0", sizeof(sz->phys));
287 
288 	rdev->device_name = sz->name;
289 	rdev->input_phys = sz->phys;
290 	usb_to_input_id(sz->usbdev, &rdev->input_id);
291 	rdev->dev.parent = dev;
292 	rdev->priv = sz;
293 	rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
294 	rdev->driver_name = DRIVER_NAME;
295 	rdev->map_name = RC_MAP_STREAMZAP;
296 
297 	ret = rc_register_device(rdev);
298 	if (ret < 0) {
299 		dev_err(dev, "remote input device register failed\n");
300 		goto out;
301 	}
302 
303 	return rdev;
304 
305 out:
306 	rc_free_device(rdev);
307 	return NULL;
308 }
309 
310 /*
311  *	streamzap_probe
312  *
313  *	Called by usb-core to associated with a candidate device
314  *	On any failure the return value is the ERROR
315  *	On success return 0
316  */
317 static int streamzap_probe(struct usb_interface *intf,
318 			   const struct usb_device_id *id)
319 {
320 	struct usb_device *usbdev = interface_to_usbdev(intf);
321 	struct usb_host_interface *iface_host;
322 	struct streamzap_ir *sz = NULL;
323 	char buf[63], name[128] = "";
324 	int retval = -ENOMEM;
325 	int pipe, maxp;
326 
327 	/* Allocate space for device driver specific data */
328 	sz = kzalloc(sizeof(struct streamzap_ir), GFP_KERNEL);
329 	if (!sz)
330 		return -ENOMEM;
331 
332 	sz->usbdev = usbdev;
333 	sz->interface = intf;
334 
335 	/* Check to ensure endpoint information matches requirements */
336 	iface_host = intf->cur_altsetting;
337 
338 	if (iface_host->desc.bNumEndpoints != 1) {
339 		dev_err(&intf->dev, "%s: Unexpected desc.bNumEndpoints (%d)\n",
340 			__func__, iface_host->desc.bNumEndpoints);
341 		retval = -ENODEV;
342 		goto free_sz;
343 	}
344 
345 	sz->endpoint = &(iface_host->endpoint[0].desc);
346 	if (!usb_endpoint_dir_in(sz->endpoint)) {
347 		dev_err(&intf->dev, "%s: endpoint doesn't match input device 02%02x\n",
348 			__func__, sz->endpoint->bEndpointAddress);
349 		retval = -ENODEV;
350 		goto free_sz;
351 	}
352 
353 	if (!usb_endpoint_xfer_int(sz->endpoint)) {
354 		dev_err(&intf->dev, "%s: endpoint attributes don't match xfer 02%02x\n",
355 			__func__, sz->endpoint->bmAttributes);
356 		retval = -ENODEV;
357 		goto free_sz;
358 	}
359 
360 	pipe = usb_rcvintpipe(usbdev, sz->endpoint->bEndpointAddress);
361 	maxp = usb_maxpacket(usbdev, pipe, usb_pipeout(pipe));
362 
363 	if (maxp == 0) {
364 		dev_err(&intf->dev, "%s: endpoint Max Packet Size is 0!?!\n",
365 			__func__);
366 		retval = -ENODEV;
367 		goto free_sz;
368 	}
369 
370 	/* Allocate the USB buffer and IRQ URB */
371 	sz->buf_in = usb_alloc_coherent(usbdev, maxp, GFP_ATOMIC, &sz->dma_in);
372 	if (!sz->buf_in)
373 		goto free_sz;
374 
375 	sz->urb_in = usb_alloc_urb(0, GFP_KERNEL);
376 	if (!sz->urb_in)
377 		goto free_buf_in;
378 
379 	sz->dev = &intf->dev;
380 	sz->buf_in_len = maxp;
381 
382 	if (usbdev->descriptor.iManufacturer
383 	    && usb_string(usbdev, usbdev->descriptor.iManufacturer,
384 			  buf, sizeof(buf)) > 0)
385 		strscpy(name, buf, sizeof(name));
386 
387 	if (usbdev->descriptor.iProduct
388 	    && usb_string(usbdev, usbdev->descriptor.iProduct,
389 			  buf, sizeof(buf)) > 0)
390 		snprintf(name + strlen(name), sizeof(name) - strlen(name),
391 			 " %s", buf);
392 
393 	sz->rdev = streamzap_init_rc_dev(sz);
394 	if (!sz->rdev)
395 		goto rc_dev_fail;
396 
397 	sz->idle = true;
398 	sz->decoder_state = PulseSpace;
399 	/* FIXME: don't yet have a way to set this */
400 	sz->timeout_enabled = true;
401 	sz->rdev->timeout = SZ_TIMEOUT * SZ_RESOLUTION;
402 	#if 0
403 	/* not yet supported, depends on patches from maxim */
404 	/* see also: LIRC_GET_REC_RESOLUTION and LIRC_SET_REC_TIMEOUT */
405 	sz->min_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
406 	sz->max_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
407 	#endif
408 
409 	sz->signal_start = ktime_get_real();
410 
411 	/* Complete final initialisations */
412 	usb_fill_int_urb(sz->urb_in, usbdev, pipe, sz->buf_in,
413 			 maxp, (usb_complete_t)streamzap_callback,
414 			 sz, sz->endpoint->bInterval);
415 	sz->urb_in->transfer_dma = sz->dma_in;
416 	sz->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
417 
418 	usb_set_intfdata(intf, sz);
419 
420 	if (usb_submit_urb(sz->urb_in, GFP_ATOMIC))
421 		dev_err(sz->dev, "urb submit failed\n");
422 
423 	dev_info(sz->dev, "Registered %s on usb%d:%d\n", name,
424 		 usbdev->bus->busnum, usbdev->devnum);
425 
426 	return 0;
427 
428 rc_dev_fail:
429 	usb_free_urb(sz->urb_in);
430 free_buf_in:
431 	usb_free_coherent(usbdev, maxp, sz->buf_in, sz->dma_in);
432 free_sz:
433 	kfree(sz);
434 
435 	return retval;
436 }
437 
438 /*
439  * streamzap_disconnect
440  *
441  * Called by the usb core when the device is removed from the system.
442  *
443  * This routine guarantees that the driver will not submit any more urbs
444  * by clearing dev->usbdev.  It is also supposed to terminate any currently
445  * active urbs.  Unfortunately, usb_bulk_msg(), used in streamzap_read(),
446  * does not provide any way to do this.
447  */
448 static void streamzap_disconnect(struct usb_interface *interface)
449 {
450 	struct streamzap_ir *sz = usb_get_intfdata(interface);
451 	struct usb_device *usbdev = interface_to_usbdev(interface);
452 
453 	usb_set_intfdata(interface, NULL);
454 
455 	if (!sz)
456 		return;
457 
458 	sz->usbdev = NULL;
459 	rc_unregister_device(sz->rdev);
460 	usb_kill_urb(sz->urb_in);
461 	usb_free_urb(sz->urb_in);
462 	usb_free_coherent(usbdev, sz->buf_in_len, sz->buf_in, sz->dma_in);
463 
464 	kfree(sz);
465 }
466 
467 static int streamzap_suspend(struct usb_interface *intf, pm_message_t message)
468 {
469 	struct streamzap_ir *sz = usb_get_intfdata(intf);
470 
471 	usb_kill_urb(sz->urb_in);
472 
473 	return 0;
474 }
475 
476 static int streamzap_resume(struct usb_interface *intf)
477 {
478 	struct streamzap_ir *sz = usb_get_intfdata(intf);
479 
480 	if (usb_submit_urb(sz->urb_in, GFP_ATOMIC)) {
481 		dev_err(sz->dev, "Error submitting urb\n");
482 		return -EIO;
483 	}
484 
485 	return 0;
486 }
487 
488 module_usb_driver(streamzap_driver);
489 
490 MODULE_AUTHOR("Jarod Wilson <jarod@wilsonet.com>");
491 MODULE_DESCRIPTION(DRIVER_DESC);
492 MODULE_LICENSE("GPL");
493