xref: /openbmc/linux/drivers/media/rc/iguanair.c (revision 060f35a317ef09101b128f399dce7ed13d019461)
1  // SPDX-License-Identifier: GPL-2.0-or-later
2  /*
3   * IguanaWorks USB IR Transceiver support
4   *
5   * Copyright (C) 2012 Sean Young <sean@mess.org>
6   */
7  
8  #include <linux/device.h>
9  #include <linux/kernel.h>
10  #include <linux/module.h>
11  #include <linux/usb.h>
12  #include <linux/usb/input.h>
13  #include <linux/slab.h>
14  #include <linux/completion.h>
15  #include <media/rc-core.h>
16  
17  #define BUF_SIZE 152
18  
19  struct iguanair {
20  	struct rc_dev *rc;
21  
22  	struct device *dev;
23  	struct usb_device *udev;
24  
25  	uint16_t version;
26  	uint8_t bufsize;
27  	uint8_t cycle_overhead;
28  
29  	/* receiver support */
30  	bool receiver_on;
31  	dma_addr_t dma_in, dma_out;
32  	uint8_t *buf_in;
33  	struct urb *urb_in, *urb_out;
34  	struct completion completion;
35  
36  	/* transmit support */
37  	bool tx_overflow;
38  	uint32_t carrier;
39  	struct send_packet *packet;
40  
41  	char name[64];
42  	char phys[64];
43  };
44  
45  #define CMD_NOP			0x00
46  #define CMD_GET_VERSION		0x01
47  #define CMD_GET_BUFSIZE		0x11
48  #define CMD_GET_FEATURES	0x10
49  #define CMD_SEND		0x15
50  #define CMD_EXECUTE		0x1f
51  #define CMD_RX_OVERFLOW		0x31
52  #define CMD_TX_OVERFLOW		0x32
53  #define CMD_RECEIVER_ON		0x12
54  #define CMD_RECEIVER_OFF	0x14
55  
56  #define DIR_IN			0xdc
57  #define DIR_OUT			0xcd
58  
59  #define MAX_IN_PACKET		8u
60  #define MAX_OUT_PACKET		(sizeof(struct send_packet) + BUF_SIZE)
61  #define TIMEOUT			1000
62  #define RX_RESOLUTION		21
63  
64  struct packet {
65  	uint16_t start;
66  	uint8_t direction;
67  	uint8_t cmd;
68  };
69  
70  struct send_packet {
71  	struct packet header;
72  	uint8_t length;
73  	uint8_t channels;
74  	uint8_t busy7;
75  	uint8_t busy4;
76  	uint8_t payload[];
77  };
78  
process_ir_data(struct iguanair * ir,unsigned len)79  static void process_ir_data(struct iguanair *ir, unsigned len)
80  {
81  	if (len >= 4 && ir->buf_in[0] == 0 && ir->buf_in[1] == 0) {
82  		switch (ir->buf_in[3]) {
83  		case CMD_GET_VERSION:
84  			if (len == 6) {
85  				ir->version = (ir->buf_in[5] << 8) |
86  							ir->buf_in[4];
87  				complete(&ir->completion);
88  			}
89  			break;
90  		case CMD_GET_BUFSIZE:
91  			if (len >= 5) {
92  				ir->bufsize = ir->buf_in[4];
93  				complete(&ir->completion);
94  			}
95  			break;
96  		case CMD_GET_FEATURES:
97  			if (len > 5) {
98  				ir->cycle_overhead = ir->buf_in[5];
99  				complete(&ir->completion);
100  			}
101  			break;
102  		case CMD_TX_OVERFLOW:
103  			ir->tx_overflow = true;
104  			fallthrough;
105  		case CMD_RECEIVER_OFF:
106  		case CMD_RECEIVER_ON:
107  		case CMD_SEND:
108  			complete(&ir->completion);
109  			break;
110  		case CMD_RX_OVERFLOW:
111  			dev_warn(ir->dev, "receive overflow\n");
112  			ir_raw_event_overflow(ir->rc);
113  			break;
114  		default:
115  			dev_warn(ir->dev, "control code %02x received\n",
116  							ir->buf_in[3]);
117  			break;
118  		}
119  	} else if (len >= 7) {
120  		struct ir_raw_event rawir = {};
121  		unsigned i;
122  		bool event = false;
123  
124  		for (i = 0; i < 7; i++) {
125  			if (ir->buf_in[i] == 0x80) {
126  				rawir.pulse = false;
127  				rawir.duration = 21845;
128  			} else {
129  				rawir.pulse = (ir->buf_in[i] & 0x80) == 0;
130  				rawir.duration = ((ir->buf_in[i] & 0x7f) + 1) *
131  								 RX_RESOLUTION;
132  			}
133  
134  			if (ir_raw_event_store_with_filter(ir->rc, &rawir))
135  				event = true;
136  		}
137  
138  		if (event)
139  			ir_raw_event_handle(ir->rc);
140  	}
141  }
142  
iguanair_rx(struct urb * urb)143  static void iguanair_rx(struct urb *urb)
144  {
145  	struct iguanair *ir;
146  	int rc;
147  
148  	if (!urb)
149  		return;
150  
151  	ir = urb->context;
152  	if (!ir)
153  		return;
154  
155  	switch (urb->status) {
156  	case 0:
157  		process_ir_data(ir, urb->actual_length);
158  		break;
159  	case -ECONNRESET:
160  	case -ENOENT:
161  	case -ESHUTDOWN:
162  		return;
163  	case -EPIPE:
164  	default:
165  		dev_dbg(ir->dev, "Error: urb status = %d\n", urb->status);
166  		break;
167  	}
168  
169  	rc = usb_submit_urb(urb, GFP_ATOMIC);
170  	if (rc && rc != -ENODEV)
171  		dev_warn(ir->dev, "failed to resubmit urb: %d\n", rc);
172  }
173  
iguanair_irq_out(struct urb * urb)174  static void iguanair_irq_out(struct urb *urb)
175  {
176  	struct iguanair *ir = urb->context;
177  
178  	if (urb->status)
179  		dev_dbg(ir->dev, "Error: out urb status = %d\n", urb->status);
180  
181  	/* if we sent an nop packet, do not expect a response */
182  	if (urb->status == 0 && ir->packet->header.cmd == CMD_NOP)
183  		complete(&ir->completion);
184  }
185  
iguanair_send(struct iguanair * ir,unsigned size)186  static int iguanair_send(struct iguanair *ir, unsigned size)
187  {
188  	int rc;
189  
190  	reinit_completion(&ir->completion);
191  
192  	ir->urb_out->transfer_buffer_length = size;
193  	rc = usb_submit_urb(ir->urb_out, GFP_KERNEL);
194  	if (rc)
195  		return rc;
196  
197  	if (wait_for_completion_timeout(&ir->completion, TIMEOUT) == 0) {
198  		usb_kill_urb(ir->urb_out);
199  		return -ETIMEDOUT;
200  	}
201  
202  	return rc;
203  }
204  
iguanair_get_features(struct iguanair * ir)205  static int iguanair_get_features(struct iguanair *ir)
206  {
207  	int rc;
208  
209  	/*
210  	 * On cold boot, the iguanair initializes on the first packet
211  	 * received but does not process that packet. Send an empty
212  	 * packet.
213  	 */
214  	ir->packet->header.start = 0;
215  	ir->packet->header.direction = DIR_OUT;
216  	ir->packet->header.cmd = CMD_NOP;
217  	iguanair_send(ir, sizeof(ir->packet->header));
218  
219  	ir->packet->header.cmd = CMD_GET_VERSION;
220  	rc = iguanair_send(ir, sizeof(ir->packet->header));
221  	if (rc) {
222  		dev_info(ir->dev, "failed to get version\n");
223  		goto out;
224  	}
225  
226  	if (ir->version < 0x205) {
227  		dev_err(ir->dev, "firmware 0x%04x is too old\n", ir->version);
228  		rc = -ENODEV;
229  		goto out;
230  	}
231  
232  	ir->bufsize = 150;
233  	ir->cycle_overhead = 65;
234  
235  	ir->packet->header.cmd = CMD_GET_BUFSIZE;
236  
237  	rc = iguanair_send(ir, sizeof(ir->packet->header));
238  	if (rc) {
239  		dev_info(ir->dev, "failed to get buffer size\n");
240  		goto out;
241  	}
242  
243  	if (ir->bufsize > BUF_SIZE) {
244  		dev_info(ir->dev, "buffer size %u larger than expected\n",
245  								ir->bufsize);
246  		ir->bufsize = BUF_SIZE;
247  	}
248  
249  	ir->packet->header.cmd = CMD_GET_FEATURES;
250  
251  	rc = iguanair_send(ir, sizeof(ir->packet->header));
252  	if (rc)
253  		dev_info(ir->dev, "failed to get features\n");
254  out:
255  	return rc;
256  }
257  
iguanair_receiver(struct iguanair * ir,bool enable)258  static int iguanair_receiver(struct iguanair *ir, bool enable)
259  {
260  	ir->packet->header.start = 0;
261  	ir->packet->header.direction = DIR_OUT;
262  	ir->packet->header.cmd = enable ? CMD_RECEIVER_ON : CMD_RECEIVER_OFF;
263  
264  	return iguanair_send(ir, sizeof(ir->packet->header));
265  }
266  
267  /*
268   * The iguanair creates the carrier by busy spinning after each half period.
269   * This is counted in CPU cycles, with the CPU running at 24MHz. It is
270   * broken down into 7-cycles and 4-cyles delays, with a preference for
271   * 4-cycle delays, minus the overhead of the loop itself (cycle_overhead).
272   */
iguanair_set_tx_carrier(struct rc_dev * dev,uint32_t carrier)273  static int iguanair_set_tx_carrier(struct rc_dev *dev, uint32_t carrier)
274  {
275  	struct iguanair *ir = dev->priv;
276  
277  	if (carrier < 25000 || carrier > 150000)
278  		return -EINVAL;
279  
280  	if (carrier != ir->carrier) {
281  		uint32_t cycles, fours, sevens;
282  
283  		ir->carrier = carrier;
284  
285  		cycles = DIV_ROUND_CLOSEST(24000000, carrier * 2) -
286  							ir->cycle_overhead;
287  
288  		/*
289  		 * Calculate minimum number of 7 cycles needed so
290  		 * we are left with a multiple of 4; so we want to have
291  		 * (sevens * 7) & 3 == cycles & 3
292  		 */
293  		sevens = (4 - cycles) & 3;
294  		fours = (cycles - sevens * 7) / 4;
295  
296  		/*
297  		 * The firmware interprets these values as a relative offset
298  		 * for a branch. Immediately following the branches, there
299  		 * 4 instructions of 7 cycles (2 bytes each) and 110
300  		 * instructions of 4 cycles (1 byte each). A relative branch
301  		 * of 0 will execute all of them, branch further for less
302  		 * cycle burning.
303  		 */
304  		ir->packet->busy7 = (4 - sevens) * 2;
305  		ir->packet->busy4 = 110 - fours;
306  	}
307  
308  	return 0;
309  }
310  
iguanair_set_tx_mask(struct rc_dev * dev,uint32_t mask)311  static int iguanair_set_tx_mask(struct rc_dev *dev, uint32_t mask)
312  {
313  	struct iguanair *ir = dev->priv;
314  
315  	if (mask > 15)
316  		return 4;
317  
318  	ir->packet->channels = mask << 4;
319  
320  	return 0;
321  }
322  
iguanair_tx(struct rc_dev * dev,unsigned * txbuf,unsigned count)323  static int iguanair_tx(struct rc_dev *dev, unsigned *txbuf, unsigned count)
324  {
325  	struct iguanair *ir = dev->priv;
326  	unsigned int i, size, p, periods;
327  	int rc;
328  
329  	/* convert from us to carrier periods */
330  	for (i = size = 0; i < count; i++) {
331  		periods = DIV_ROUND_CLOSEST(txbuf[i] * ir->carrier, 1000000);
332  		while (periods) {
333  			p = min(periods, 127u);
334  			if (size >= ir->bufsize) {
335  				rc = -EINVAL;
336  				goto out;
337  			}
338  			ir->packet->payload[size++] = p | ((i & 1) ? 0x80 : 0);
339  			periods -= p;
340  		}
341  	}
342  
343  	ir->packet->header.start = 0;
344  	ir->packet->header.direction = DIR_OUT;
345  	ir->packet->header.cmd = CMD_SEND;
346  	ir->packet->length = size;
347  
348  	ir->tx_overflow = false;
349  
350  	rc = iguanair_send(ir, sizeof(*ir->packet) + size);
351  
352  	if (rc == 0 && ir->tx_overflow)
353  		rc = -EOVERFLOW;
354  
355  out:
356  	return rc ? rc : count;
357  }
358  
iguanair_open(struct rc_dev * rdev)359  static int iguanair_open(struct rc_dev *rdev)
360  {
361  	struct iguanair *ir = rdev->priv;
362  	int rc;
363  
364  	rc = iguanair_receiver(ir, true);
365  	if (rc == 0)
366  		ir->receiver_on = true;
367  
368  	return rc;
369  }
370  
iguanair_close(struct rc_dev * rdev)371  static void iguanair_close(struct rc_dev *rdev)
372  {
373  	struct iguanair *ir = rdev->priv;
374  	int rc;
375  
376  	rc = iguanair_receiver(ir, false);
377  	ir->receiver_on = false;
378  	if (rc && rc != -ENODEV)
379  		dev_warn(ir->dev, "failed to disable receiver: %d\n", rc);
380  }
381  
iguanair_probe(struct usb_interface * intf,const struct usb_device_id * id)382  static int iguanair_probe(struct usb_interface *intf,
383  			  const struct usb_device_id *id)
384  {
385  	struct usb_device *udev = interface_to_usbdev(intf);
386  	struct iguanair *ir;
387  	struct rc_dev *rc;
388  	int ret, pipein, pipeout;
389  	struct usb_host_interface *idesc;
390  
391  	idesc = intf->cur_altsetting;
392  	if (idesc->desc.bNumEndpoints < 2)
393  		return -ENODEV;
394  
395  	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
396  	rc = rc_allocate_device(RC_DRIVER_IR_RAW);
397  	if (!ir || !rc) {
398  		ret = -ENOMEM;
399  		goto out;
400  	}
401  
402  	ir->buf_in = usb_alloc_coherent(udev, MAX_IN_PACKET, GFP_KERNEL,
403  								&ir->dma_in);
404  	ir->packet = usb_alloc_coherent(udev, MAX_OUT_PACKET, GFP_KERNEL,
405  								&ir->dma_out);
406  	ir->urb_in = usb_alloc_urb(0, GFP_KERNEL);
407  	ir->urb_out = usb_alloc_urb(0, GFP_KERNEL);
408  
409  	if (!ir->buf_in || !ir->packet || !ir->urb_in || !ir->urb_out ||
410  	    !usb_endpoint_is_int_in(&idesc->endpoint[0].desc) ||
411  	    !usb_endpoint_is_int_out(&idesc->endpoint[1].desc)) {
412  		ret = -ENOMEM;
413  		goto out;
414  	}
415  
416  	ir->rc = rc;
417  	ir->dev = &intf->dev;
418  	ir->udev = udev;
419  
420  	init_completion(&ir->completion);
421  	pipeout = usb_sndintpipe(udev,
422  				idesc->endpoint[1].desc.bEndpointAddress);
423  	usb_fill_int_urb(ir->urb_out, udev, pipeout, ir->packet, MAX_OUT_PACKET,
424  						iguanair_irq_out, ir, 1);
425  	ir->urb_out->transfer_dma = ir->dma_out;
426  	ir->urb_out->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
427  
428  	pipein = usb_rcvintpipe(udev, idesc->endpoint[0].desc.bEndpointAddress);
429  	usb_fill_int_urb(ir->urb_in, udev, pipein, ir->buf_in, MAX_IN_PACKET,
430  							 iguanair_rx, ir, 1);
431  	ir->urb_in->transfer_dma = ir->dma_in;
432  	ir->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
433  
434  	ret = usb_submit_urb(ir->urb_in, GFP_KERNEL);
435  	if (ret) {
436  		dev_warn(&intf->dev, "failed to submit urb: %d\n", ret);
437  		goto out;
438  	}
439  
440  	ret = iguanair_get_features(ir);
441  	if (ret)
442  		goto out2;
443  
444  	snprintf(ir->name, sizeof(ir->name),
445  		"IguanaWorks USB IR Transceiver version 0x%04x", ir->version);
446  
447  	usb_make_path(ir->udev, ir->phys, sizeof(ir->phys));
448  
449  	rc->device_name = ir->name;
450  	rc->input_phys = ir->phys;
451  	usb_to_input_id(ir->udev, &rc->input_id);
452  	rc->dev.parent = &intf->dev;
453  	rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
454  	rc->priv = ir;
455  	rc->open = iguanair_open;
456  	rc->close = iguanair_close;
457  	rc->s_tx_mask = iguanair_set_tx_mask;
458  	rc->s_tx_carrier = iguanair_set_tx_carrier;
459  	rc->tx_ir = iguanair_tx;
460  	rc->driver_name = KBUILD_MODNAME;
461  	rc->map_name = RC_MAP_RC6_MCE;
462  	rc->min_timeout = 1;
463  	rc->timeout = IR_DEFAULT_TIMEOUT;
464  	rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
465  	rc->rx_resolution = RX_RESOLUTION;
466  
467  	iguanair_set_tx_carrier(rc, 38000);
468  	iguanair_set_tx_mask(rc, 0);
469  
470  	ret = rc_register_device(rc);
471  	if (ret < 0) {
472  		dev_err(&intf->dev, "failed to register rc device %d", ret);
473  		goto out2;
474  	}
475  
476  	usb_set_intfdata(intf, ir);
477  
478  	return 0;
479  out2:
480  	usb_kill_urb(ir->urb_in);
481  	usb_kill_urb(ir->urb_out);
482  out:
483  	if (ir) {
484  		usb_free_urb(ir->urb_in);
485  		usb_free_urb(ir->urb_out);
486  		usb_free_coherent(udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
487  		usb_free_coherent(udev, MAX_OUT_PACKET, ir->packet,
488  								ir->dma_out);
489  	}
490  	rc_free_device(rc);
491  	kfree(ir);
492  	return ret;
493  }
494  
iguanair_disconnect(struct usb_interface * intf)495  static void iguanair_disconnect(struct usb_interface *intf)
496  {
497  	struct iguanair *ir = usb_get_intfdata(intf);
498  
499  	rc_unregister_device(ir->rc);
500  	usb_set_intfdata(intf, NULL);
501  	usb_kill_urb(ir->urb_in);
502  	usb_kill_urb(ir->urb_out);
503  	usb_free_urb(ir->urb_in);
504  	usb_free_urb(ir->urb_out);
505  	usb_free_coherent(ir->udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
506  	usb_free_coherent(ir->udev, MAX_OUT_PACKET, ir->packet, ir->dma_out);
507  	kfree(ir);
508  }
509  
iguanair_suspend(struct usb_interface * intf,pm_message_t message)510  static int iguanair_suspend(struct usb_interface *intf, pm_message_t message)
511  {
512  	struct iguanair *ir = usb_get_intfdata(intf);
513  	int rc = 0;
514  
515  	if (ir->receiver_on) {
516  		rc = iguanair_receiver(ir, false);
517  		if (rc)
518  			dev_warn(ir->dev, "failed to disable receiver for suspend\n");
519  	}
520  
521  	usb_kill_urb(ir->urb_in);
522  	usb_kill_urb(ir->urb_out);
523  
524  	return rc;
525  }
526  
iguanair_resume(struct usb_interface * intf)527  static int iguanair_resume(struct usb_interface *intf)
528  {
529  	struct iguanair *ir = usb_get_intfdata(intf);
530  	int rc;
531  
532  	rc = usb_submit_urb(ir->urb_in, GFP_KERNEL);
533  	if (rc)
534  		dev_warn(&intf->dev, "failed to submit urb: %d\n", rc);
535  
536  	if (ir->receiver_on) {
537  		rc = iguanair_receiver(ir, true);
538  		if (rc)
539  			dev_warn(ir->dev, "failed to enable receiver after resume\n");
540  	}
541  
542  	return rc;
543  }
544  
545  static const struct usb_device_id iguanair_table[] = {
546  	{ USB_DEVICE(0x1781, 0x0938) },
547  	{ }
548  };
549  
550  static struct usb_driver iguanair_driver = {
551  	.name =	KBUILD_MODNAME,
552  	.probe = iguanair_probe,
553  	.disconnect = iguanair_disconnect,
554  	.suspend = iguanair_suspend,
555  	.resume = iguanair_resume,
556  	.reset_resume = iguanair_resume,
557  	.id_table = iguanair_table,
558  	.soft_unbind = 1	/* we want to disable receiver on unbind */
559  };
560  
561  module_usb_driver(iguanair_driver);
562  
563  MODULE_DESCRIPTION("IguanaWorks USB IR Transceiver");
564  MODULE_AUTHOR("Sean Young <sean@mess.org>");
565  MODULE_LICENSE("GPL");
566  MODULE_DEVICE_TABLE(usb, iguanair_table);
567  
568