summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-rcar.c
blob: 43b51045aa47a0c2a57c2faaec63e1dcb0b24cca (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
/*
 * Renesas R-Car GPIO Support
 *
 *  Copyright (C) 2014 Renesas Electronics Corporation
 *  Copyright (C) 2013 Magnus Damm
 *
 * 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
 *
 * 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.
 */

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/spinlock.h>
#include <linux/slab.h>

struct gpio_rcar_priv {
	void __iomem *base;
	spinlock_t lock;
	struct platform_device *pdev;
	struct gpio_chip gpio_chip;
	struct irq_chip irq_chip;
	struct clk *clk;
	unsigned int irq_parent;
	bool has_both_edge_trigger;
	bool needs_clk;
};

#define IOINTSEL 0x00	/* General IO/Interrupt Switching Register */
#define INOUTSEL 0x04	/* General Input/Output Switching Register */
#define OUTDT 0x08	/* General Output Register */
#define INDT 0x0c	/* General Input Register */
#define INTDT 0x10	/* Interrupt Display Register */
#define INTCLR 0x14	/* Interrupt Clear Register */
#define INTMSK 0x18	/* Interrupt Mask Register */
#define MSKCLR 0x1c	/* Interrupt Mask Clear Register */
#define POSNEG 0x20	/* Positive/Negative Logic Select Register */
#define EDGLEVEL 0x24	/* Edge/level Select Register */
#define FILONOFF 0x28	/* Chattering Prevention On/Off Register */
#define BOTHEDGE 0x4c	/* One Edge/Both Edge Select Register */

#define RCAR_MAX_GPIO_PER_BANK		32

static inline u32 gpio_rcar_read(struct gpio_rcar_priv *p, int offs)
{
	return ioread32(p->base + offs);
}

static inline void gpio_rcar_write(struct gpio_rcar_priv *p, int offs,
				   u32 value)
{
	iowrite32(value, p->base + offs);
}

static void gpio_rcar_modify_bit(struct gpio_rcar_priv *p, int offs,
				 int bit, bool value)
{
	u32 tmp = gpio_rcar_read(p, offs);

	if (value)
		tmp |= BIT(bit);
	else
		tmp &= ~BIT(bit);

	gpio_rcar_write(p, offs, tmp);
}

static void gpio_rcar_irq_disable(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct gpio_rcar_priv *p = gpiochip_get_data(gc);

	gpio_rcar_write(p, INTMSK, ~BIT(irqd_to_hwirq(d)));
}

static void gpio_rcar_irq_enable(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct gpio_rcar_priv *p = gpiochip_get_data(gc);

	gpio_rcar_write(p, MSKCLR, BIT(irqd_to_hwirq(d)));
}

static void gpio_rcar_config_interrupt_input_mode(struct gpio_rcar_priv *p,
						  unsigned int hwirq,
						  bool active_high_rising_edge,
						  bool level_trigger,
						  bool both)
{
	unsigned long flags;

	/* follow steps in the GPIO documentation for
	 * "Setting Edge-Sensitive Interrupt Input Mode" and
	 * "Setting Level-Sensitive Interrupt Input Mode"
	 */

	spin_lock_irqsave(&p->lock, flags);

	/* Configure postive or negative logic in POSNEG */
	gpio_rcar_modify_bit(p, POSNEG, hwirq, !active_high_rising_edge);

	/* Configure edge or level trigger in EDGLEVEL */
	gpio_rcar_modify_bit(p, EDGLEVEL, hwirq, !level_trigger);

	/* Select one edge or both edges in BOTHEDGE */
	if (p->has_both_edge_trigger)
		gpio_rcar_modify_bit(p, BOTHEDGE, hwirq, both);

	/* Select "Interrupt Input Mode" in IOINTSEL */
	gpio_rcar_modify_bit(p, IOINTSEL, hwirq, true);

	/* Write INTCLR in case of edge trigger */
	if (!level_trigger)
		gpio_rcar_write(p, INTCLR, BIT(hwirq));

	spin_unlock_irqrestore(&p->lock, flags);
}

static int gpio_rcar_irq_set_type(struct irq_data *d, unsigned int type)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct gpio_rcar_priv *p = gpiochip_get_data(gc);
	unsigned int hwirq = irqd_to_hwirq(d);

	dev_dbg(&p->pdev->dev, "sense irq = %d, type = %d\n", hwirq, type);

	switch (type & IRQ_TYPE_SENSE_MASK) {
	case IRQ_TYPE_LEVEL_HIGH:
		gpio_rcar_config_interrupt_input_mode(p, hwirq, true, true,
						      false);
		break;
	case IRQ_TYPE_LEVEL_LOW:
		gpio_rcar_config_interrupt_input_mode(p, hwirq, false, true,
						      false);
		break;
	case IRQ_TYPE_EDGE_RISING:
		gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
						      false);
		break;
	case IRQ_TYPE_EDGE_FALLING:
		gpio_rcar_config_interrupt_input_mode(p, hwirq, false, false,
						      false);
		break;
	case IRQ_TYPE_EDGE_BOTH:
		if (!p->has_both_edge_trigger)
			return -EINVAL;
		gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
						      true);
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static int gpio_rcar_irq_set_wake(struct irq_data *d, unsigned int on)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct gpio_rcar_priv *p = gpiochip_get_data(gc);
	int error;

	if (p->irq_parent) {
		error = irq_set_irq_wake(p->irq_parent, on);
		if (error) {
			dev_dbg(&p->pdev->dev,
				"irq %u doesn't support irq_set_wake\n",
				p->irq_parent);
			p->irq_parent = 0;
		}
	}

	if (!p->clk)
		return 0;

	if (on)
		clk_enable(p->clk);
	else
		clk_disable(p->clk);

	return 0;
}

static irqreturn_t gpio_rcar_irq_handler(int irq, void *dev_id)
{
	struct gpio_rcar_priv *p = dev_id;
	u32 pending;
	unsigned int offset, irqs_handled = 0;

	while ((pending = gpio_rcar_read(p, INTDT) &
			  gpio_rcar_read(p, INTMSK))) {
		offset = __ffs(pending);
		gpio_rcar_write(p, INTCLR, BIT(offset));
		generic_handle_irq(irq_find_mapping(p->gpio_chip.irqdomain,
						    offset));
		irqs_handled++;
	}

	return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
}

static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip,
						       unsigned int gpio,
						       bool output)
{
	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
	unsigned long flags;

	/* follow steps in the GPIO documentation for
	 * "Setting General Output Mode" and
	 * "Setting General Input Mode"
	 */

	spin_lock_irqsave(&p->lock, flags);

	/* Configure postive logic in POSNEG */
	gpio_rcar_modify_bit(p, POSNEG, gpio, false);

	/* Select "General Input/Output Mode" in IOINTSEL */
	gpio_rcar_modify_bit(p, IOINTSEL, gpio, false);

	/* Select Input Mode or Output Mode in INOUTSEL */
	gpio_rcar_modify_bit(p, INOUTSEL, gpio, output);

	spin_unlock_irqrestore(&p->lock, flags);
}

static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset)
{
	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
	int error;

	error = pm_runtime_get_sync(&p->pdev->dev);
	if (error < 0)
		return error;

	error = pinctrl_gpio_request(chip->base + offset);
	if (error)
		pm_runtime_put(&p->pdev->dev);

	return error;
}

static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset)
{
	struct gpio_rcar_priv *p = gpiochip_get_data(chip);

	pinctrl_gpio_free(chip->base + offset);

	/*
	 * Set the GPIO as an input to ensure that the next GPIO request won't
	 * drive the GPIO pin as an output.
	 */
	gpio_rcar_config_general_input_output_mode(chip, offset, false);

	pm_runtime_put(&p->pdev->dev);
}

static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset)
{
	gpio_rcar_config_general_input_output_mode(chip, offset, false);
	return 0;
}

static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset)
{
	u32 bit = BIT(offset);

	/* testing on r8a7790 shows that INDT does not show correct pin state
	 * when configured as output, so use OUTDT in case of output pins */
	if (gpio_rcar_read(gpiochip_get_data(chip), INOUTSEL) & bit)
		return !!(gpio_rcar_read(gpiochip_get_data(chip), OUTDT) & bit);
	else
		return !!(gpio_rcar_read(gpiochip_get_data(chip), INDT) & bit);
}

static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value)
{
	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
	unsigned long flags;

	spin_lock_irqsave(&p->lock, flags);
	gpio_rcar_modify_bit(p, OUTDT, offset, value);
	spin_unlock_irqrestore(&p->lock, flags);
}

static void gpio_rcar_set_multiple(struct gpio_chip *chip, unsigned long *mask,
				   unsigned long *bits)
{
	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
	unsigned long flags;
	u32 val, bankmask;

	bankmask = mask[0] & GENMASK(chip->ngpio - 1, 0);
	if (!bankmask)
		return;

	spin_lock_irqsave(&p->lock, flags);
	val = gpio_rcar_read(p, OUTDT);
	val &= ~bankmask;
	val |= (bankmask & bits[0]);
	gpio_rcar_write(p, OUTDT, val);
	spin_unlock_irqrestore(&p->lock, flags);
}

static int gpio_rcar_direction_output(struct gpio_chip *chip, unsigned offset,
				      int value)
{
	/* write GPIO value to output before selecting output mode of pin */
	gpio_rcar_set(chip, offset, value);
	gpio_rcar_config_general_input_output_mode(chip, offset, true);
	return 0;
}

struct gpio_rcar_info {
	bool has_both_edge_trigger;
	bool needs_clk;
};

static const struct gpio_rcar_info gpio_rcar_info_gen1 = {
	.has_both_edge_trigger = false,
	.needs_clk = false,
};

static const struct gpio_rcar_info gpio_rcar_info_gen2 = {
	.has_both_edge_trigger = true,
	.needs_clk = true,
};

static const struct of_device_id gpio_rcar_of_table[] = {
	{
		.compatible = "renesas,gpio-r8a7743",
		/* RZ/G1 GPIO is identical to R-Car Gen2. */
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-r8a7790",
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-r8a7791",
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-r8a7792",
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-r8a7793",
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-r8a7794",
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-r8a7795",
		/* Gen3 GPIO is identical to Gen2. */
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-r8a7796",
		/* Gen3 GPIO is identical to Gen2. */
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,rcar-gen1-gpio",
		.data = &gpio_rcar_info_gen1,
	}, {
		.compatible = "renesas,rcar-gen2-gpio",
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,rcar-gen3-gpio",
		/* Gen3 GPIO is identical to Gen2. */
		.data = &gpio_rcar_info_gen2,
	}, {
		.compatible = "renesas,gpio-rcar",
		.data = &gpio_rcar_info_gen1,
	}, {
		/* Terminator */
	},
};

MODULE_DEVICE_TABLE(of, gpio_rcar_of_table);

static int gpio_rcar_parse_dt(struct gpio_rcar_priv *p, unsigned int *npins)
{
	struct device_node *np = p->pdev->dev.of_node;
	const struct of_device_id *match;
	const struct gpio_rcar_info *info;
	struct of_phandle_args args;
	int ret;

	match = of_match_node(gpio_rcar_of_table, np);
	if (!match)
		return -EINVAL;

	info = match->data;

	ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &args);
	*npins = ret == 0 ? args.args[2] : RCAR_MAX_GPIO_PER_BANK;
	p->has_both_edge_trigger = info->has_both_edge_trigger;
	p->needs_clk = info->needs_clk;

	if (*npins == 0 || *npins > RCAR_MAX_GPIO_PER_BANK) {
		dev_warn(&p->pdev->dev,
			 "Invalid number of gpio lines %u, using %u\n", *npins,
			 RCAR_MAX_GPIO_PER_BANK);
		*npins = RCAR_MAX_GPIO_PER_BANK;
	}

	return 0;
}

static int gpio_rcar_probe(struct platform_device *pdev)
{
	struct gpio_rcar_priv *p;
	struct resource *io, *irq;
	struct gpio_chip *gpio_chip;
	struct irq_chip *irq_chip;
	struct device *dev = &pdev->dev;
	const char *name = dev_name(dev);
	unsigned int npins;
	int ret;

	p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
	if (!p)
		return -ENOMEM;

	p->pdev = pdev;
	spin_lock_init(&p->lock);

	/* Get device configuration from DT node */
	ret = gpio_rcar_parse_dt(p, &npins);
	if (ret < 0)
		return ret;

	platform_set_drvdata(pdev, p);

	p->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(p->clk)) {
		if (p->needs_clk) {
			dev_err(dev, "unable to get clock\n");
			ret = PTR_ERR(p->clk);
			goto err0;
		}
		p->clk = NULL;
	}

	pm_runtime_enable(dev);

	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);

	if (!io || !irq) {
		dev_err(dev, "missing IRQ or IOMEM\n");
		ret = -EINVAL;
		goto err0;
	}

	p->base = devm_ioremap_nocache(dev, io->start, resource_size(io));
	if (!p->base) {
		dev_err(dev, "failed to remap I/O memory\n");
		ret = -ENXIO;
		goto err0;
	}

	gpio_chip = &p->gpio_chip;
	gpio_chip->request = gpio_rcar_request;
	gpio_chip->free = gpio_rcar_free;
	gpio_chip->direction_input = gpio_rcar_direction_input;
	gpio_chip->get = gpio_rcar_get;
	gpio_chip->direction_output = gpio_rcar_direction_output;
	gpio_chip->set = gpio_rcar_set;
	gpio_chip->set_multiple = gpio_rcar_set_multiple;
	gpio_chip->label = name;
	gpio_chip->parent = dev;
	gpio_chip->owner = THIS_MODULE;
	gpio_chip->base = -1;
	gpio_chip->ngpio = npins;

	irq_chip = &p->irq_chip;
	irq_chip->name = name;
	irq_chip->parent_device = dev;
	irq_chip->irq_mask = gpio_rcar_irq_disable;
	irq_chip->irq_unmask = gpio_rcar_irq_enable;
	irq_chip->irq_set_type = gpio_rcar_irq_set_type;
	irq_chip->irq_set_wake = gpio_rcar_irq_set_wake;
	irq_chip->flags	= IRQCHIP_SET_TYPE_MASKED | IRQCHIP_MASK_ON_SUSPEND;

	ret = gpiochip_add_data(gpio_chip, p);
	if (ret) {
		dev_err(dev, "failed to add GPIO controller\n");
		goto err0;
	}

	ret = gpiochip_irqchip_add(gpio_chip, irq_chip, 0, handle_level_irq,
				   IRQ_TYPE_NONE);
	if (ret) {
		dev_err(dev, "cannot add irqchip\n");
		goto err1;
	}

	p->irq_parent = irq->start;
	if (devm_request_irq(dev, irq->start, gpio_rcar_irq_handler,
			     IRQF_SHARED, name, p)) {
		dev_err(dev, "failed to request IRQ\n");
		ret = -ENOENT;
		goto err1;
	}

	dev_info(dev, "driving %d GPIOs\n", npins);

	return 0;

err1:
	gpiochip_remove(gpio_chip);
err0:
	pm_runtime_disable(dev);
	return ret;
}

static int gpio_rcar_remove(struct platform_device *pdev)
{
	struct gpio_rcar_priv *p = platform_get_drvdata(pdev);

	gpiochip_remove(&p->gpio_chip);

	pm_runtime_disable(&pdev->dev);
	return 0;
}

static struct platform_driver gpio_rcar_device_driver = {
	.probe		= gpio_rcar_probe,
	.remove		= gpio_rcar_remove,
	.driver		= {
		.name	= "gpio_rcar",
		.of_match_table = of_match_ptr(gpio_rcar_of_table),
	}
};

module_platform_driver(gpio_rcar_device_driver);

MODULE_AUTHOR("Magnus Damm");
MODULE_DESCRIPTION("Renesas R-Car GPIO Driver");
MODULE_LICENSE("GPL v2");