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/usb.h>
25#include <linux/usb/input.h>
26#include <media/rc-core.h>
27
28#define DRIVER_NAME	"streamzap"
29#define DRIVER_DESC	"Streamzap Remote Control driver"
30
31#define USB_STREAMZAP_VENDOR_ID		0x0e9c
32#define USB_STREAMZAP_PRODUCT_ID	0x0000
33
34/* table of devices that work with this driver */
35static const struct usb_device_id streamzap_table[] = {
36	/* Streamzap Remote Control */
37	{ USB_DEVICE(USB_STREAMZAP_VENDOR_ID, USB_STREAMZAP_PRODUCT_ID) },
38	/* Terminating entry */
39	{ }
40};
41
42MODULE_DEVICE_TABLE(usb, streamzap_table);
43
44#define SZ_PULSE_MASK 0xf0
45#define SZ_SPACE_MASK 0x0f
46#define SZ_TIMEOUT    0xff
47#define SZ_RESOLUTION 256
48
49/* number of samples buffered */
50#define SZ_BUF_LEN 128
51
52enum StreamzapDecoderState {
53	PulseSpace,
54	FullPulse,
55	FullSpace,
56	IgnorePulse
57};
58
59/* structure to hold our device specific stuff */
60struct streamzap_ir {
61	/* ir-core */
62	struct rc_dev *rdev;
63
64	/* core device info */
65	struct device *dev;
66
67	/* usb */
68	struct urb		*urb_in;
69
70	/* buffer & dma */
71	unsigned char		*buf_in;
72	dma_addr_t		dma_in;
73	unsigned int		buf_in_len;
74
75	/* track what state we're in */
76	enum StreamzapDecoderState decoder_state;
77
78	char			phys[64];
79};
80
81
82/* local function prototypes */
83static int streamzap_probe(struct usb_interface *interface,
84			   const struct usb_device_id *id);
85static void streamzap_disconnect(struct usb_interface *interface);
86static void streamzap_callback(struct urb *urb);
87static int streamzap_suspend(struct usb_interface *intf, pm_message_t message);
88static int streamzap_resume(struct usb_interface *intf);
89
90/* usb specific object needed to register this driver with the usb subsystem */
91static struct usb_driver streamzap_driver = {
92	.name =		DRIVER_NAME,
93	.probe =	streamzap_probe,
94	.disconnect =	streamzap_disconnect,
95	.suspend =	streamzap_suspend,
96	.resume =	streamzap_resume,
97	.id_table =	streamzap_table,
98};
99
100static void sz_push(struct streamzap_ir *sz, struct ir_raw_event rawir)
101{
102	dev_dbg(sz->dev, "Storing %s with duration %u us\n",
103		(rawir.pulse ? "pulse" : "space"), rawir.duration);
104	ir_raw_event_store_with_filter(sz->rdev, &rawir);
105}
106
107static void sz_push_full_pulse(struct streamzap_ir *sz,
108			       unsigned char value)
109{
110	struct ir_raw_event rawir = {
111		.pulse = true,
112		.duration = value * SZ_RESOLUTION + SZ_RESOLUTION / 2,
113	};
114
115	sz_push(sz, rawir);
116}
117
118static void sz_push_half_pulse(struct streamzap_ir *sz,
119			       unsigned char value)
120{
121	sz_push_full_pulse(sz, (value & SZ_PULSE_MASK) >> 4);
122}
123
124static void sz_push_full_space(struct streamzap_ir *sz,
125			       unsigned char value)
126{
127	struct ir_raw_event rawir = {
128		.pulse = false,
129		.duration = value * SZ_RESOLUTION + SZ_RESOLUTION / 2,
130	};
131
132	sz_push(sz, rawir);
133}
134
135static void sz_push_half_space(struct streamzap_ir *sz,
136			       unsigned long value)
137{
138	sz_push_full_space(sz, value & SZ_SPACE_MASK);
139}
140
141/*
142 * streamzap_callback - usb IRQ handler callback
143 *
144 * This procedure is invoked on reception of data from
145 * the usb remote.
146 */
147static void streamzap_callback(struct urb *urb)
148{
149	struct streamzap_ir *sz;
150	unsigned int i;
151	int len;
152
153	if (!urb)
154		return;
155
156	sz = urb->context;
157	len = urb->actual_length;
158
159	switch (urb->status) {
160	case -ECONNRESET:
161	case -ENOENT:
162	case -ESHUTDOWN:
163		/*
164		 * this urb is terminated, clean up.
165		 * sz might already be invalid at this point
166		 */
167		dev_err(sz->dev, "urb terminated, status: %d\n", urb->status);
168		return;
169	default:
170		break;
171	}
172
173	dev_dbg(sz->dev, "%s: received urb, len %d\n", __func__, len);
174	for (i = 0; i < len; i++) {
175		dev_dbg(sz->dev, "sz->buf_in[%d]: %x\n",
176			i, (unsigned char)sz->buf_in[i]);
177		switch (sz->decoder_state) {
178		case PulseSpace:
179			if ((sz->buf_in[i] & SZ_PULSE_MASK) ==
180				SZ_PULSE_MASK) {
181				sz->decoder_state = FullPulse;
182				continue;
183			} else if ((sz->buf_in[i] & SZ_SPACE_MASK)
184					== SZ_SPACE_MASK) {
185				sz_push_half_pulse(sz, sz->buf_in[i]);
186				sz->decoder_state = FullSpace;
187				continue;
188			} else {
189				sz_push_half_pulse(sz, sz->buf_in[i]);
190				sz_push_half_space(sz, sz->buf_in[i]);
191			}
192			break;
193		case FullPulse:
194			sz_push_full_pulse(sz, sz->buf_in[i]);
195			sz->decoder_state = IgnorePulse;
196			break;
197		case FullSpace:
198			if (sz->buf_in[i] == SZ_TIMEOUT) {
199				struct ir_raw_event rawir = {
200					.pulse = false,
201					.duration = sz->rdev->timeout
202				};
203				sz_push(sz, rawir);
204			} else {
205				sz_push_full_space(sz, sz->buf_in[i]);
206			}
207			sz->decoder_state = PulseSpace;
208			break;
209		case IgnorePulse:
210			if ((sz->buf_in[i] & SZ_SPACE_MASK) ==
211				SZ_SPACE_MASK) {
212				sz->decoder_state = FullSpace;
213				continue;
214			}
215			sz_push_half_space(sz, sz->buf_in[i]);
216			sz->decoder_state = PulseSpace;
217			break;
218		}
219	}
220
221	ir_raw_event_handle(sz->rdev);
222	usb_submit_urb(urb, GFP_ATOMIC);
223}
224
225static struct rc_dev *streamzap_init_rc_dev(struct streamzap_ir *sz,
226					    struct usb_device *usbdev)
227{
228	struct rc_dev *rdev;
229	struct device *dev = sz->dev;
230	int ret;
231
232	rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
233	if (!rdev)
234		goto out;
235
236	usb_make_path(usbdev, sz->phys, sizeof(sz->phys));
237	strlcat(sz->phys, "/input0", sizeof(sz->phys));
238
239	rdev->device_name = "Streamzap PC Remote Infrared Receiver";
240	rdev->input_phys = sz->phys;
241	usb_to_input_id(usbdev, &rdev->input_id);
242	rdev->dev.parent = dev;
243	rdev->priv = sz;
244	rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
245	rdev->driver_name = DRIVER_NAME;
246	rdev->map_name = RC_MAP_STREAMZAP;
247	rdev->rx_resolution = SZ_RESOLUTION;
248
249	ret = rc_register_device(rdev);
250	if (ret < 0) {
251		dev_err(dev, "remote input device register failed\n");
252		goto out;
253	}
254
255	return rdev;
256
257out:
258	rc_free_device(rdev);
259	return NULL;
260}
261
262/*
263 *	streamzap_probe
264 *
265 *	Called by usb-core to associated with a candidate device
266 *	On any failure the return value is the ERROR
267 *	On success return 0
268 */
269static int streamzap_probe(struct usb_interface *intf,
270			   const struct usb_device_id *id)
271{
272	struct usb_device *usbdev = interface_to_usbdev(intf);
273	struct usb_endpoint_descriptor *endpoint;
274	struct usb_host_interface *iface_host;
275	struct streamzap_ir *sz = NULL;
276	int retval = -ENOMEM;
277	int pipe, maxp;
278
279	/* Allocate space for device driver specific data */
280	sz = kzalloc(sizeof(struct streamzap_ir), GFP_KERNEL);
281	if (!sz)
282		return -ENOMEM;
283
284	/* Check to ensure endpoint information matches requirements */
285	iface_host = intf->cur_altsetting;
286
287	if (iface_host->desc.bNumEndpoints != 1) {
288		dev_err(&intf->dev, "%s: Unexpected desc.bNumEndpoints (%d)\n",
289			__func__, iface_host->desc.bNumEndpoints);
290		retval = -ENODEV;
291		goto free_sz;
292	}
293
294	endpoint = &iface_host->endpoint[0].desc;
295	if (!usb_endpoint_dir_in(endpoint)) {
296		dev_err(&intf->dev, "%s: endpoint doesn't match input device 02%02x\n",
297			__func__, endpoint->bEndpointAddress);
298		retval = -ENODEV;
299		goto free_sz;
300	}
301
302	if (!usb_endpoint_xfer_int(endpoint)) {
303		dev_err(&intf->dev, "%s: endpoint attributes don't match xfer 02%02x\n",
304			__func__, endpoint->bmAttributes);
305		retval = -ENODEV;
306		goto free_sz;
307	}
308
309	pipe = usb_rcvintpipe(usbdev, endpoint->bEndpointAddress);
310	maxp = usb_maxpacket(usbdev, pipe);
311
312	if (maxp == 0) {
313		dev_err(&intf->dev, "%s: endpoint Max Packet Size is 0!?!\n",
314			__func__);
315		retval = -ENODEV;
316		goto free_sz;
317	}
318
319	/* Allocate the USB buffer and IRQ URB */
320	sz->buf_in = usb_alloc_coherent(usbdev, maxp, GFP_ATOMIC, &sz->dma_in);
321	if (!sz->buf_in)
322		goto free_sz;
323
324	sz->urb_in = usb_alloc_urb(0, GFP_KERNEL);
325	if (!sz->urb_in)
326		goto free_buf_in;
327
328	sz->dev = &intf->dev;
329	sz->buf_in_len = maxp;
330
331	sz->rdev = streamzap_init_rc_dev(sz, usbdev);
332	if (!sz->rdev)
333		goto rc_dev_fail;
334
335	sz->decoder_state = PulseSpace;
336	/* FIXME: don't yet have a way to set this */
337	sz->rdev->timeout = SZ_TIMEOUT * SZ_RESOLUTION;
338	#if 0
339	/* not yet supported, depends on patches from maxim */
340	/* see also: LIRC_GET_REC_RESOLUTION and LIRC_SET_REC_TIMEOUT */
341	sz->min_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
342	sz->max_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
343	#endif
344
345	/* Complete final initialisations */
346	usb_fill_int_urb(sz->urb_in, usbdev, pipe, sz->buf_in,
347			 maxp, streamzap_callback, sz, endpoint->bInterval);
348	sz->urb_in->transfer_dma = sz->dma_in;
349	sz->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
350
351	usb_set_intfdata(intf, sz);
352
353	if (usb_submit_urb(sz->urb_in, GFP_ATOMIC))
354		dev_err(sz->dev, "urb submit failed\n");
355
356	return 0;
357
358rc_dev_fail:
359	usb_free_urb(sz->urb_in);
360free_buf_in:
361	usb_free_coherent(usbdev, maxp, sz->buf_in, sz->dma_in);
362free_sz:
363	kfree(sz);
364
365	return retval;
366}
367
368/*
369 * streamzap_disconnect
370 *
371 * Called by the usb core when the device is removed from the system.
372 *
373 * This routine guarantees that the driver will not submit any more urbs
374 * by clearing dev->usbdev.  It is also supposed to terminate any currently
375 * active urbs.  Unfortunately, usb_bulk_msg(), used in streamzap_read(),
376 * does not provide any way to do this.
377 */
378static void streamzap_disconnect(struct usb_interface *interface)
379{
380	struct streamzap_ir *sz = usb_get_intfdata(interface);
381	struct usb_device *usbdev = interface_to_usbdev(interface);
382
383	usb_set_intfdata(interface, NULL);
384
385	if (!sz)
386		return;
387
388	rc_unregister_device(sz->rdev);
389	usb_kill_urb(sz->urb_in);
390	usb_free_urb(sz->urb_in);
391	usb_free_coherent(usbdev, sz->buf_in_len, sz->buf_in, sz->dma_in);
392
393	kfree(sz);
394}
395
396static int streamzap_suspend(struct usb_interface *intf, pm_message_t message)
397{
398	struct streamzap_ir *sz = usb_get_intfdata(intf);
399
400	usb_kill_urb(sz->urb_in);
401
402	return 0;
403}
404
405static int streamzap_resume(struct usb_interface *intf)
406{
407	struct streamzap_ir *sz = usb_get_intfdata(intf);
408
409	if (usb_submit_urb(sz->urb_in, GFP_NOIO)) {
410		dev_err(sz->dev, "Error submitting urb\n");
411		return -EIO;
412	}
413
414	return 0;
415}
416
417module_usb_driver(streamzap_driver);
418
419MODULE_AUTHOR("Jarod Wilson <jarod@wilsonet.com>");
420MODULE_DESCRIPTION(DRIVER_DESC);
421MODULE_LICENSE("GPL");
422