summaryrefslogtreecommitdiffstats
path: root/drivers/base/regmap/regmap-irq.c
blob: 82692068d3cbe8dfa4cc5fdb6b544b74168255ea (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
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
/*
 * regmap based irq_chip
 *
 * Copyright 2011 Wolfson Microelectronics plc
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/export.h>
#include <linux/device.h>
#include <linux/regmap.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>

#include "internal.h"

struct regmap_irq_chip_data {
	struct mutex lock;
	struct irq_chip irq_chip;

	struct regmap *map;
	const struct regmap_irq_chip *chip;

	int irq_base;
	struct irq_domain *domain;

	int irq;
	int wake_count;

	void *status_reg_buf;
	unsigned int *status_buf;
	unsigned int *mask_buf;
	unsigned int *mask_buf_def;
	unsigned int *wake_buf;

	unsigned int irq_reg_stride;
};

static inline const
struct regmap_irq *irq_to_regmap_irq(struct regmap_irq_chip_data *data,
				     int irq)
{
	return &data->chip->irqs[irq];
}

static void regmap_irq_lock(struct irq_data *data)
{
	struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);

	mutex_lock(&d->lock);
}

static void regmap_irq_sync_unlock(struct irq_data *data)
{
	struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
	struct regmap *map = d->map;
	int i, ret;
	u32 reg;

	if (d->chip->runtime_pm) {
		ret = pm_runtime_get_sync(map->dev);
		if (ret < 0)
			dev_err(map->dev, "IRQ sync failed to resume: %d\n",
				ret);
	}

	/*
	 * If there's been a change in the mask write it back to the
	 * hardware.  We rely on the use of the regmap core cache to
	 * suppress pointless writes.
	 */
	for (i = 0; i < d->chip->num_regs; i++) {
		reg = d->chip->mask_base +
			(i * map->reg_stride * d->irq_reg_stride);
		if (d->chip->mask_invert)
			ret = regmap_update_bits(d->map, reg,
					 d->mask_buf_def[i], ~d->mask_buf[i]);
		else
			ret = regmap_update_bits(d->map, reg,
					 d->mask_buf_def[i], d->mask_buf[i]);
		if (ret != 0)
			dev_err(d->map->dev, "Failed to sync masks in %x\n",
				reg);

		reg = d->chip->wake_base +
			(i * map->reg_stride * d->irq_reg_stride);
		if (d->wake_buf) {
			if (d->chip->wake_invert)
				ret = regmap_update_bits(d->map, reg,
							 d->mask_buf_def[i],
							 ~d->wake_buf[i]);
			else
				ret = regmap_update_bits(d->map, reg,
							 d->mask_buf_def[i],
							 d->wake_buf[i]);
			if (ret != 0)
				dev_err(d->map->dev,
					"Failed to sync wakes in %x: %d\n",
					reg, ret);
		}

		if (!d->chip->init_ack_masked)
			continue;
		/*
		 * Ack all the masked interrupts uncondictionly,
		 * OR if there is masked interrupt which hasn't been Acked,
		 * it'll be ignored in irq handler, then may introduce irq storm
		 */
		if (d->mask_buf[i] && (d->chip->ack_base || d->chip->use_ack)) {
			reg = d->chip->ack_base +
				(i * map->reg_stride * d->irq_reg_stride);
			ret = regmap_write(map, reg, d->mask_buf[i]);
			if (ret != 0)
				dev_err(d->map->dev, "Failed to ack 0x%x: %d\n",
					reg, ret);
		}
	}

	if (d->chip->runtime_pm)
		pm_runtime_put(map->dev);

	/* If we've changed our wakeup count propagate it to the parent */
	if (d->wake_count < 0)
		for (i = d->wake_count; i < 0; i++)
			irq_set_irq_wake(d->irq, 0);
	else if (d->wake_count > 0)
		for (i = 0; i < d->wake_count; i++)
			irq_set_irq_wake(d->irq, 1);

	d->wake_count = 0;

	mutex_unlock(&d->lock);
}

static void regmap_irq_enable(struct irq_data *data)
{
	struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
	struct regmap *map = d->map;
	const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->hwirq);

	d->mask_buf[irq_data->reg_offset / map->reg_stride] &= ~irq_data->mask;
}

static void regmap_irq_disable(struct irq_data *data)
{
	struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
	struct regmap *map = d->map;
	const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->hwirq);

	d->mask_buf[irq_data->reg_offset / map->reg_stride] |= irq_data->mask;
}

static int regmap_irq_set_wake(struct irq_data *data, unsigned int on)
{
	struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
	struct regmap *map = d->map;
	const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->hwirq);

	if (on) {
		if (d->wake_buf)
			d->wake_buf[irq_data->reg_offset / map->reg_stride]
				&= ~irq_data->mask;
		d->wake_count++;
	} else {
		if (d->wake_buf)
			d->wake_buf[irq_data->reg_offset / map->reg_stride]
				|= irq_data->mask;
		d->wake_count--;
	}

	return 0;
}

static const struct irq_chip regmap_irq_chip = {
	.irq_bus_lock		= regmap_irq_lock,
	.irq_bus_sync_unlock	= regmap_irq_sync_unlock,
	.irq_disable		= regmap_irq_disable,
	.irq_enable		= regmap_irq_enable,
	.irq_set_wake		= regmap_irq_set_wake,
};

static irqreturn_t regmap_irq_thread(int irq, void *d)
{
	struct regmap_irq_chip_data *data = d;
	const struct regmap_irq_chip *chip = data->chip;
	struct regmap *map = data->map;
	int ret, i;
	bool handled = false;
	u32 reg;

	if (chip->runtime_pm) {
		ret = pm_runtime_get_sync(map->dev);
		if (ret < 0) {
			dev_err(map->dev, "IRQ thread failed to resume: %d\n",
				ret);
			pm_runtime_put(map->dev);
			return IRQ_NONE;
		}
	}

	/*
	 * Read in the statuses, using a single bulk read if possible
	 * in order to reduce the I/O overheads.
	 */
	if (!map->use_single_rw && map->reg_stride == 1 &&
	    data->irq_reg_stride == 1) {
		u8 *buf8 = data->status_reg_buf;
		u16 *buf16 = data->status_reg_buf;
		u32 *buf32 = data->status_reg_buf;

		BUG_ON(!data->status_reg_buf);

		ret = regmap_bulk_read(map, chip->status_base,
				       data->status_reg_buf,
				       chip->num_regs);
		if (ret != 0) {
			dev_err(map->dev, "Failed to read IRQ status: %d\n",
				ret);
			return IRQ_NONE;
		}

		for (i = 0; i < data->chip->num_regs; i++) {
			switch (map->format.val_bytes) {
			case 1:
				data->status_buf[i] = buf8[i];
				break;
			case 2:
				data->status_buf[i] = buf16[i];
				break;
			case 4:
				data->status_buf[i] = buf32[i];
				break;
			default:
				BUG();
				return IRQ_NONE;
			}
		}

	} else {
		for (i = 0; i < data->chip->num_regs; i++) {
			ret = regmap_read(map, chip->status_base +
					  (i * map->reg_stride
					   * data->irq_reg_stride),
					  &data->status_buf[i]);

			if (ret != 0) {
				dev_err(map->dev,
					"Failed to read IRQ status: %d\n",
					ret);
				if (chip->runtime_pm)
					pm_runtime_put(map->dev);
				return IRQ_NONE;
			}
		}
	}

	/*
	 * Ignore masked IRQs and ack if we need to; we ack early so
	 * there is no race between handling and acknowleding the
	 * interrupt.  We assume that typically few of the interrupts
	 * will fire simultaneously so don't worry about overhead from
	 * doing a write per register.
	 */
	for (i = 0; i < data->chip->num_regs; i++) {
		data->status_buf[i] &= ~data->mask_buf[i];

		if (data->status_buf[i] && (chip->ack_base || chip->use_ack)) {
			reg = chip->ack_base +
				(i * map->reg_stride * data->irq_reg_stride);
			ret = regmap_write(map, reg, data->status_buf[i]);
			if (ret != 0)
				dev_err(map->dev, "Failed to ack 0x%x: %d\n",
					reg, ret);
		}
	}

	for (i = 0; i < chip->num_irqs; i++) {
		if (data->status_buf[chip->irqs[i].reg_offset /
				     map->reg_stride] & chip->irqs[i].mask) {
			handle_nested_irq(irq_find_mapping(data->domain, i));
			handled = true;
		}
	}

	if (chip->runtime_pm)
		pm_runtime_put(map->dev);

	if (handled)
		return IRQ_HANDLED;
	else
		return IRQ_NONE;
}

static int regmap_irq_map(struct irq_domain *h, unsigned int virq,
			  irq_hw_number_t hw)
{
	struct regmap_irq_chip_data *data = h->host_data;

	irq_set_chip_data(virq, data);
	irq_set_chip(virq, &data->irq_chip);
	irq_set_nested_thread(virq, 1);

	/* ARM needs us to explicitly flag the IRQ as valid
	 * and will set them noprobe when we do so. */
#ifdef CONFIG_ARM
	set_irq_flags(virq, IRQF_VALID);
#else
	irq_set_noprobe(virq);
#endif

	return 0;
}

static struct irq_domain_ops regmap_domain_ops = {
	.map	= regmap_irq_map,
	.xlate	= irq_domain_xlate_twocell,
};

/**
 * regmap_add_irq_chip(): Use standard regmap IRQ controller handling
 *
 * map:       The regmap for the device.
 * irq:       The IRQ the device uses to signal interrupts
 * irq_flags: The IRQF_ flags to use for the primary interrupt.
 * chip:      Configuration for the interrupt controller.
 * data:      Runtime data structure for the controller, allocated on success
 *
 * Returns 0 on success or an errno on failure.
 *
 * In order for this to be efficient the chip really should use a
 * register cache.  The chip driver is responsible for restoring the
 * register values used by the IRQ controller over suspend and resume.
 */
int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
			int irq_base, const struct regmap_irq_chip *chip,
			struct regmap_irq_chip_data **data)
{
	struct regmap_irq_chip_data *d;
	int i;
	int ret = -ENOMEM;
	u32 reg;

	for (i = 0; i < chip->num_irqs; i++) {
		if (chip->irqs[i].reg_offset % map->reg_stride)
			return -EINVAL;
		if (chip->irqs[i].reg_offset / map->reg_stride >=
		    chip->num_regs)
			return -EINVAL;
	}

	if (irq_base) {
		irq_base = irq_alloc_descs(irq_base, 0, chip->num_irqs, 0);
		if (irq_base < 0) {
			dev_warn(map->dev, "Failed to allocate IRQs: %d\n",
				 irq_base);
			return irq_base;
		}
	}

	d = kzalloc(sizeof(*d), GFP_KERNEL);
	if (!d)
		return -ENOMEM;

	*data = d;

	d->status_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
				GFP_KERNEL);
	if (!d->status_buf)
		goto err_alloc;

	d->mask_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
			      GFP_KERNEL);
	if (!d->mask_buf)
		goto err_alloc;

	d->mask_buf_def = kzalloc(sizeof(unsigned int) * chip->num_regs,
				  GFP_KERNEL);
	if (!d->mask_buf_def)
		goto err_alloc;

	if (chip->wake_base) {
		d->wake_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
				      GFP_KERNEL);
		if (!d->wake_buf)
			goto err_alloc;
	}

	d->irq_chip = regmap_irq_chip;
	d->irq_chip.name = chip->name;
	d->irq = irq;
	d->map = map;
	d->chip = chip;
	d->irq_base = irq_base;

	if (chip->irq_reg_stride)
		d->irq_reg_stride = chip->irq_reg_stride;
	else
		d->irq_reg_stride = 1;

	if (!map->use_single_rw && map->reg_stride == 1 &&
	    d->irq_reg_stride == 1) {
		d->status_reg_buf = kmalloc(map->format.val_bytes *
					    chip->num_regs, GFP_KERNEL);
		if (!d->status_reg_buf)
			goto err_alloc;
	}

	mutex_init(&d->lock);

	for (i = 0; i < chip->num_irqs; i++)
		d->mask_buf_def[chip->irqs[i].reg_offset / map->reg_stride]
			|= chip->irqs[i].mask;

	/* Mask all the interrupts by default */
	for (i = 0; i < chip->num_regs; i++) {
		d->mask_buf[i] = d->mask_buf_def[i];
		reg = chip->mask_base +
			(i * map->reg_stride * d->irq_reg_stride);
		if (chip->mask_invert)
			ret = regmap_update_bits(map, reg,
					 d->mask_buf[i], ~d->mask_buf[i]);
		else
			ret = regmap_update_bits(map, reg,
					 d->mask_buf[i], d->mask_buf[i]);
		if (ret != 0) {
			dev_err(map->dev, "Failed to set masks in 0x%x: %d\n",
				reg, ret);
			goto err_alloc;
		}

		if (!chip->init_ack_masked)
			continue;

		/* Ack masked but set interrupts */
		reg = chip->status_base +
			(i * map->reg_stride * d->irq_reg_stride);
		ret = regmap_read(map, reg, &d->status_buf[i]);
		if (ret != 0) {
			dev_err(map->dev, "Failed to read IRQ status: %d\n",
				ret);
			goto err_alloc;
		}

		if (d->status_buf[i] && (chip->ack_base || chip->use_ack)) {
			reg = chip->ack_base +
				(i * map->reg_stride * d->irq_reg_stride);
			ret = regmap_write(map, reg,
					d->status_buf[i] & d->mask_buf[i]);
			if (ret != 0) {
				dev_err(map->dev, "Failed to ack 0x%x: %d\n",
					reg, ret);
				goto err_alloc;
			}
		}
	}

	/* Wake is disabled by default */
	if (d->wake_buf) {
		for (i = 0; i < chip->num_regs; i++) {
			d->wake_buf[i] = d->mask_buf_def[i];
			reg = chip->wake_base +
				(i * map->reg_stride * d->irq_reg_stride);

			if (chip->wake_invert)
				ret = regmap_update_bits(map, reg,
							 d->mask_buf_def[i],
							 0);
			else
				ret = regmap_update_bits(map, reg,
							 d->mask_buf_def[i],
							 d->wake_buf[i]);
			if (ret != 0) {
				dev_err(map->dev, "Failed to set masks in 0x%x: %d\n",
					reg, ret);
				goto err_alloc;
			}
		}
	}

	if (irq_base)
		d->domain = irq_domain_add_legacy(map->dev->of_node,
						  chip->num_irqs, irq_base, 0,
						  &regmap_domain_ops, d);
	else
		d->domain = irq_domain_add_linear(map->dev->of_node,
						  chip->num_irqs,
						  &regmap_domain_ops, d);
	if (!d->domain) {
		dev_err(map->dev, "Failed to create IRQ domain\n");
		ret = -ENOMEM;
		goto err_alloc;
	}

	ret = request_threaded_irq(irq, NULL, regmap_irq_thread, irq_flags,
				   chip->name, d);
	if (ret != 0) {
		dev_err(map->dev, "Failed to request IRQ %d for %s: %d\n",
			irq, chip->name, ret);
		goto err_domain;
	}

	return 0;

err_domain:
	/* Should really dispose of the domain but... */
err_alloc:
	kfree(d->wake_buf);
	kfree(d->mask_buf_def);
	kfree(d->mask_buf);
	kfree(d->status_buf);
	kfree(d->status_reg_buf);
	kfree(d);
	return ret;
}
EXPORT_SYMBOL_GPL(regmap_add_irq_chip);

/**
 * regmap_del_irq_chip(): Stop interrupt handling for a regmap IRQ chip
 *
 * @irq: Primary IRQ for the device
 * @d:   regmap_irq_chip_data allocated by regmap_add_irq_chip()
 */
void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d)
{
	if (!d)
		return;

	free_irq(irq, d);
	/* We should unmap the domain but... */
	kfree(d->wake_buf);
	kfree(d->mask_buf_def);
	kfree(d->mask_buf);
	kfree(d->status_reg_buf);
	kfree(d->status_buf);
	kfree(d);
}
EXPORT_SYMBOL_GPL(regmap_del_irq_chip);

/**
 * regmap_irq_chip_get_base(): Retrieve interrupt base for a regmap IRQ chip
 *
 * Useful for drivers to request their own IRQs.
 *
 * @data: regmap_irq controller to operate on.
 */
int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data)
{
	WARN_ON(!data->irq_base);
	return data->irq_base;
}
EXPORT_SYMBOL_GPL(regmap_irq_chip_get_base);

/**
 * regmap_irq_get_virq(): Map an interrupt on a chip to a virtual IRQ
 *
 * Useful for drivers to request their own IRQs.
 *
 * @data: regmap_irq controller to operate on.
 * @irq: index of the interrupt requested in the chip IRQs
 */
int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq)
{
	/* Handle holes in the IRQ list */
	if (!data->chip->irqs[irq].mask)
		return -EINVAL;

	return irq_create_mapping(data->domain, irq);
}
EXPORT_SYMBOL_GPL(regmap_irq_get_virq);

/**
 * regmap_irq_get_domain(): Retrieve the irq_domain for the chip
 *
 * Useful for drivers to request their own IRQs and for integration
 * with subsystems.  For ease of integration NULL is accepted as a
 * domain, allowing devices to just call this even if no domain is
 * allocated.
 *
 * @data: regmap_irq controller to operate on.
 */
struct irq_domain *regmap_irq_get_domain(struct regmap_irq_chip_data *data)
{
	if (data)
		return data->domain;
	else
		return NULL;
}
EXPORT_SYMBOL_GPL(regmap_irq_get_domain);