xref: /openbmc/linux/drivers/media/rc/streamzap.c (revision 9a29f5fc)
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 */
35 static 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 
42 MODULE_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 
52 enum StreamzapDecoderState {
53 	PulseSpace,
54 	FullPulse,
55 	FullSpace,
56 	IgnorePulse
57 };
58 
59 /* structure to hold our device specific stuff */
60 struct 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 */
83 static int streamzap_probe(struct usb_interface *interface,
84 			   const struct usb_device_id *id);
85 static void streamzap_disconnect(struct usb_interface *interface);
86 static void streamzap_callback(struct urb *urb);
87 static int streamzap_suspend(struct usb_interface *intf, pm_message_t message);
88 static int streamzap_resume(struct usb_interface *intf);
89 
90 /* usb specific object needed to register this driver with the usb subsystem */
91 static 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 
100 static 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 
107 static 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 
118 static 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 
124 static 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 
135 static 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  */
147 static 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 
225 static 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 
257 out:
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  */
269 static 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 
358 rc_dev_fail:
359 	usb_free_urb(sz->urb_in);
360 free_buf_in:
361 	usb_free_coherent(usbdev, maxp, sz->buf_in, sz->dma_in);
362 free_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  */
378 static 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 
396 static 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 
405 static 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 
417 module_usb_driver(streamzap_driver);
418 
419 MODULE_AUTHOR("Jarod Wilson <jarod@wilsonet.com>");
420 MODULE_DESCRIPTION(DRIVER_DESC);
421 MODULE_LICENSE("GPL");
422