aboutsummaryrefslogtreecommitdiff
path: root/drivers/media/video/cx23885/cx23885-input.c
blob: 8d306d8bb61cd60260eb6b4906efa851b3328e4e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
/*
 *  Driver for the Conexant CX23885/7/8 PCIe bridge
 *
 *  Infrared remote control input device
 *
 *  Most of this file is
 *
 *  Copyright (C) 2009  Andy Walls <awalls@radix.net>
 *
 *  However, the cx23885_input_{init,fini} functions contained herein are
 *  derived from Linux kernel files linux/media/video/.../...-input.c marked as:
 *
 *  Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
 *  Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it>
 *		       Markus Rechberger <mrechberger@gmail.com>
 *		       Mauro Carvalho Chehab <mchehab@infradead.org>
 *		       Sascha Sommer <saschasommer@freenet.de>
 *  Copyright (C) 2004, 2005 Chris Pascoe
 *  Copyright (C) 2003, 2004 Gerd Knorr
 *  Copyright (C) 2003 Pavel Machek
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 *  02110-1301, USA.
 */

#include <linux/input.h>
#include <linux/slab.h>
#include <media/ir-common.h>
#include <media/v4l2-subdev.h>

#include "cx23885.h"

#define RC5_BITS		14
#define RC5_HALF_BITS		(2*RC5_BITS)
#define RC5_HALF_BITS_MASK	((1 << RC5_HALF_BITS) - 1)

#define RC5_START_BITS_NORMAL	0x3 /* Command range  0 -  63 */
#define RC5_START_BITS_EXTENDED	0x2 /* Command range 64 - 127 */

#define RC5_EXTENDED_COMMAND_OFFSET	64

#define MODULE_NAME "cx23885"

static inline unsigned int rc5_command(u32 rc5_baseband)
{
	return RC5_INSTR(rc5_baseband) +
		((RC5_START(rc5_baseband) == RC5_START_BITS_EXTENDED)
			? RC5_EXTENDED_COMMAND_OFFSET : 0);
}

static void cx23885_input_process_raw_rc5(struct cx23885_dev *dev)
{
	struct card_ir *ir_input = dev->ir_input;
	unsigned int code, command;
	u32 rc5;

	/* Ignore codes that are too short to be valid RC-5 */
	if (ir_input->last_bit < (RC5_HALF_BITS - 1))
		return;

	/* The library has the manchester coding backwards; XOR to adapt. */
	code = (ir_input->code & RC5_HALF_BITS_MASK) ^ RC5_HALF_BITS_MASK;
	rc5 = ir_rc5_decode(code);

	switch (RC5_START(rc5)) {
	case RC5_START_BITS_NORMAL:
		break;
	case RC5_START_BITS_EXTENDED:
		/* Don't allow if the remote only emits standard commands */
		if (ir_input->start == RC5_START_BITS_NORMAL)
			return;
		break;
	default:
		return;
	}

	if (ir_input->addr != RC5_ADDR(rc5))
		return;

	/* Don't generate a keypress for RC-5 auto-repeated keypresses */
	command = rc5_command(rc5);
	if (RC5_TOGGLE(rc5) != RC5_TOGGLE(ir_input->last_rc5) ||
	    command != rc5_command(ir_input->last_rc5) ||
	    /* Catch T == 0, CMD == 0 (e.g. '0') as first keypress after init */
	    RC5_START(ir_input->last_rc5) == 0) {
		/* This keypress is differnet: not an auto repeat */
		ir_input_nokey(ir_input->dev, &ir_input->ir);
		ir_input_keydown(ir_input->dev, &ir_input->ir, command);
	}
	ir_input->last_rc5 = rc5;

	/* Schedule when we should do the key up event: ir_input_nokey() */
	mod_timer(&ir_input->timer_keyup,
		  jiffies + msecs_to_jiffies(ir_input->rc5_key_timeout));
}

static void cx23885_input_next_pulse_width_rc5(struct cx23885_dev *dev,
					       u32 ns_pulse)
{
	const int rc5_quarterbit_ns = 444444; /* 32 cycles/36 kHz/2 = 444 us */
	struct card_ir *ir_input = dev->ir_input;
	int i, level, quarterbits, halfbits;

	if (!ir_input->active) {
		ir_input->active = 1;
		/* assume an initial space that we may not detect or measure */
		ir_input->code = 0;
		ir_input->last_bit = 0;
	}

	if (ns_pulse == V4L2_SUBDEV_IR_PULSE_RX_SEQ_END) {
		ir_input->last_bit++; /* Account for the final space */
		ir_input->active = 0;
		cx23885_input_process_raw_rc5(dev);
		return;
	}

	level = (ns_pulse & V4L2_SUBDEV_IR_PULSE_LEVEL_MASK) ? 1 : 0;

	/* Skip any leading space to sync to the start bit */
	if (ir_input->last_bit == 0 && level == 0)
		return;

	/*
	 * With valid RC-5 we can get up to two consecutive half-bits in a
	 * single pulse measurment.  Experiments have shown that the duration
	 * of a half-bit can vary.  Make sure we always end up with an even
	 * number of quarter bits at the same level (mark or space).
	 */
	ns_pulse &= V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS;
	quarterbits = ns_pulse / rc5_quarterbit_ns;
	if (quarterbits & 1)
		quarterbits++;
	halfbits = quarterbits / 2;

	for (i = 0; i < halfbits; i++) {
		ir_input->last_bit++;
		ir_input->code |= (level << ir_input->last_bit);

		if (ir_input->last_bit >= RC5_HALF_BITS-1) {
			ir_input->active = 0;
			cx23885_input_process_raw_rc5(dev);
			/*
			 * If level is 1, a leading mark is invalid for RC5.
			 * If level is 0, we scan past extra intial space.
			 * Either way we don't want to reactivate collecting
			 * marks or spaces here with any left over half-bits.
			 */
			break;
		}
	}
}

static void cx23885_input_process_pulse_widths_rc5(struct cx23885_dev *dev,
						   bool add_eom)
{
	struct card_ir *ir_input = dev->ir_input;
	struct ir_input_state *ir_input_state = &ir_input->ir;

	u32 ns_pulse[RC5_HALF_BITS+1];
	ssize_t num = 0;
	int count, i;

	do {
		v4l2_subdev_call(dev->sd_ir, ir, rx_read, (u8 *) ns_pulse,
				 sizeof(ns_pulse), &num);

		count = num / sizeof(u32);

		/* Append an end of Rx seq, if the caller requested */
		if (add_eom && count < ARRAY_SIZE(ns_pulse)) {
			ns_pulse[count] = V4L2_SUBDEV_IR_PULSE_RX_SEQ_END;
			count++;
		}

		/* Just drain the Rx FIFO, if we're called, but not RC-5 */
		if (ir_input_state->ir_type != IR_TYPE_RC5)
			continue;

		for (i = 0; i < count; i++)
			cx23885_input_next_pulse_width_rc5(dev, ns_pulse[i]);
	} while (num != 0);
}

void cx23885_input_rx_work_handler(struct cx23885_dev *dev, u32 events)
{
	struct v4l2_subdev_ir_parameters params;
	int overrun, data_available;

	if (dev->sd_ir == NULL || events == 0)
		return;

	switch (dev->board) {
	case CX23885_BOARD_HAUPPAUGE_HVR1850:
	case CX23885_BOARD_HAUPPAUGE_HVR1290:
		/*
		 * The only board we handle right now.  However other boards
		 * using the CX2388x integrated IR controller should be similar
		 */
		break;
	default:
		return;
	}

	overrun = events & (V4L2_SUBDEV_IR_RX_SW_FIFO_OVERRUN |
			    V4L2_SUBDEV_IR_RX_HW_FIFO_OVERRUN);

	data_available = events & (V4L2_SUBDEV_IR_RX_END_OF_RX_DETECTED |
				   V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ);

	if (overrun) {
		/* If there was a FIFO overrun, stop the device */
		v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
		params.enable = false;
		/* Mitigate race with cx23885_input_ir_stop() */
		params.shutdown = atomic_read(&dev->ir_input_stopping);
		v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
	}

	if (data_available)
		cx23885_input_process_pulse_widths_rc5(dev, overrun);

	if (overrun) {
		/* If there was a FIFO overrun, clear & restart the device */
		params.enable = true;
		/* Mitigate race with cx23885_input_ir_stop() */
		params.shutdown = atomic_read(&dev->ir_input_stopping);
		v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
	}
}

static void cx23885_input_ir_start(struct cx23885_dev *dev)
{
	struct card_ir *ir_input = dev->ir_input;
	struct ir_input_state *ir_input_state = &ir_input->ir;
	struct v4l2_subdev_ir_parameters params;

	if (dev->sd_ir == NULL)
		return;

	atomic_set(&dev->ir_input_stopping, 0);

	/* keyup timer set up, if needed */
	switch (dev->board) {
	case CX23885_BOARD_HAUPPAUGE_HVR1850:
	case CX23885_BOARD_HAUPPAUGE_HVR1290:
		setup_timer(&ir_input->timer_keyup,
			    ir_rc5_timer_keyup,	/* Not actually RC-5 specific */
			    (unsigned long) ir_input);
		if (ir_input_state->ir_type == IR_TYPE_RC5) {
			/*
			 * RC-5 repeats a held key every
			 * 64 bits * (2 * 32/36000) sec/bit = 113.778 ms
			 */
			ir_input->rc5_key_timeout = 115;
		}
		break;
	}

	v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
	switch (dev->board) {
	case CX23885_BOARD_HAUPPAUGE_HVR1850:
	case CX23885_BOARD_HAUPPAUGE_HVR1290:
		/*
		 * The IR controller on this board only returns pulse widths.
		 * Any other mode setting will fail to set up the device.
		*/
		params.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
		params.enable = true;
		params.interrupt_enable = true;
		params.shutdown = false;

		/* Setup for baseband compatible with both RC-5 and RC-6A */
		params.modulation = false;
		/* RC-5:  2,222,222 ns = 1/36 kHz * 32 cycles * 2 marks * 1.25*/
		/* RC-6A: 3,333,333 ns = 1/36 kHz * 16 cycles * 6 marks * 1.25*/
		params.max_pulse_width = 3333333; /* ns */
		/* RC-5:    666,667 ns = 1/36 kHz * 32 cycles * 1 mark * 0.75 */
		/* RC-6A:   333,333 ns = 1/36 kHz * 16 cycles * 1 mark * 0.75 */
		params.noise_filter_min_width = 333333; /* ns */
		/*
		 * This board has inverted receive sense:
		 * mark is received as low logic level;
		 * falling edges are detected as rising edges; etc.
		 */
		params.invert = true;
		break;
	}
	v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
}

static void cx23885_input_ir_stop(struct cx23885_dev *dev)
{
	struct card_ir *ir_input = dev->ir_input;
	struct v4l2_subdev_ir_parameters params;

	if (dev->sd_ir == NULL)
		return;

	/*
	 * Stop the sd_ir subdevice from generating notifications and
	 * scheduling work.
	 * It is shutdown this way in order to mitigate a race with
	 * cx23885_input_rx_work_handler() in the overrun case, which could
	 * re-enable the subdevice.
	 */
	atomic_set(&dev->ir_input_stopping, 1);
	v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
	while (params.shutdown == false) {
		params.enable = false;
		params.interrupt_enable = false;
		params.shutdown = true;
		v4l2_subdev_call(dev->sd_ir, ir, rx_s_parameters, &params);
		v4l2_subdev_call(dev->sd_ir, ir, rx_g_parameters, &params);
	}

	flush_scheduled_work();

	switch (dev->board) {
	case CX23885_BOARD_HAUPPAUGE_HVR1850:
	case CX23885_BOARD_HAUPPAUGE_HVR1290:
		del_timer_sync(&ir_input->timer_keyup);
		break;
	}
}

int cx23885_input_init(struct cx23885_dev *dev)
{
	struct card_ir *ir;
	struct input_dev *input_dev;
	char *ir_codes = NULL;
	int ir_type, ir_addr, ir_start;
	int ret;

	/*
	 * If the IR device (hardware registers, chip, GPIO lines, etc.) isn't
	 * encapsulated in a v4l2_subdev, then I'm not going to deal with it.
	 */
	if (dev->sd_ir == NULL)
		return -ENODEV;

	switch (dev->board) {
	case CX23885_BOARD_HAUPPAUGE_HVR1850:
	case CX23885_BOARD_HAUPPAUGE_HVR1290:
		/* Parameters for the grey Hauppauge remote for the HVR-1850 */
		ir_codes = RC_MAP_HAUPPAUGE_NEW;
		ir_type = IR_TYPE_RC5;
		ir_addr = 0x1e; /* RC-5 system bits emitted by the remote */
		ir_start = RC5_START_BITS_NORMAL; /* A basic RC-5 remote */
		break;
	}
	if (ir_codes == NULL)
		return -ENODEV;

	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!ir || !input_dev) {
		ret = -ENOMEM;
		goto err_out_free;
	}

	ir->dev = input_dev;
	ir->addr = ir_addr;
	ir->start = ir_start;

	/* init input device */
	snprintf(ir->name, sizeof(ir->name), "cx23885 IR (%s)",
		 cx23885_boards[dev->board].name);
	snprintf(ir->phys, sizeof(ir->phys), "pci-%s/ir0", pci_name(dev->pci));

	ret = ir_input_init(input_dev, &ir->ir, ir_type);
	if (ret < 0)
		goto err_out_free;

	input_dev->name = ir->name;
	input_dev->phys = ir->phys;
	input_dev->id.bustype = BUS_PCI;
	input_dev->id.version = 1;
	if (dev->pci->subsystem_vendor) {
		input_dev->id.vendor  = dev->pci->subsystem_vendor;
		input_dev->id.product = dev->pci->subsystem_device;
	} else {
		input_dev->id.vendor  = dev->pci->vendor;
		input_dev->id.product = dev->pci->device;
	}
	input_dev->dev.parent = &dev->pci->dev;

	dev->ir_input = ir;
	cx23885_input_ir_start(dev);

	ret = ir_input_register(ir->dev, ir_codes, NULL, MODULE_NAME);
	if (ret)
		goto err_out_stop;

	return 0;

err_out_stop:
	cx23885_input_ir_stop(dev);
	dev->ir_input = NULL;
err_out_free:
	kfree(ir);
	return ret;
}

void cx23885_input_fini(struct cx23885_dev *dev)
{
	/* Always stop the IR hardware from generating interrupts */
	cx23885_input_ir_stop(dev);

	if (dev->ir_input == NULL)
		return;
	ir_input_unregister(dev->ir_input->dev);
	kfree(dev->ir_input);
	dev->ir_input = NULL;
}