summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-rcar.c
blob: 6038966ab045529b071242424e49b12237db316a (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
/*
 * Renesas R-Car GPIO Support
 *
 *  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/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/irqdomain.h>
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_data/gpio-rcar.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/slab.h>

struct gpio_rcar_priv {
	void __iomem *base;
	spinlock_t lock;
	struct gpio_rcar_config config;
	struct platform_device *pdev;
	struct gpio_chip gpio_chip;
	struct irq_chip irq_chip;
	struct irq_domain *irq_domain;
};

#define IOINTSEL 0x00
#define INOUTSEL 0x04
#define OUTDT 0x08
#define INDT 0x0c
#define INTDT 0x10
#define INTCLR 0x14
#define INTMSK 0x18
#define MSKCLR 0x1c
#define POSNEG 0x20
#define EDGLEVEL 0x24
#define FILONOFF 0x28
#define BOTHEDGE 0x4c

#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_rcar_priv *p = irq_data_get_irq_chip_data(d);

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

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

	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->config.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_rcar_priv *p = irq_data_get_irq_chip_data(d);
	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->config.has_both_edge_trigger)
			return -EINVAL;
		gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
						      true);
		break;
	default:
		return -EINVAL;
	}
	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))) {
		offset = __ffs(pending);
		gpio_rcar_write(p, INTCLR, BIT(offset));
		generic_handle_irq(irq_find_mapping(p->irq_domain, offset));
		irqs_handled++;
	}

	return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
}

static inline struct gpio_rcar_priv *gpio_to_priv(struct gpio_chip *chip)
{
	return container_of(chip, struct gpio_rcar_priv, gpio_chip);
}

static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip,
						       unsigned int gpio,
						       bool output)
{
	struct gpio_rcar_priv *p = gpio_to_priv(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)
{
	return pinctrl_request_gpio(chip->base + offset);
}

static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset)
{
	pinctrl_free_gpio(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);
}

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(gpio_to_priv(chip), INOUTSEL) & bit)
		return (int)(gpio_rcar_read(gpio_to_priv(chip), OUTDT) & bit);
	else
		return (int)(gpio_rcar_read(gpio_to_priv(chip), INDT) & bit);
}

static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value)
{
	struct gpio_rcar_priv *p = gpio_to_priv(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 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;
}

static int gpio_rcar_to_irq(struct gpio_chip *chip, unsigned offset)
{
	return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset);
}

static int gpio_rcar_irq_domain_map(struct irq_domain *h, unsigned int virq,
				 irq_hw_number_t hw)
{
	struct gpio_rcar_priv *p = h->host_data;

	dev_dbg(&p->pdev->dev, "map hw irq = %d, virq = %d\n", (int)hw, virq);

	irq_set_chip_data(virq, h->host_data);
	irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
	set_irq_flags(virq, IRQF_VALID); /* kill me now */
	return 0;
}

static struct irq_domain_ops gpio_rcar_irq_domain_ops = {
	.map	= gpio_rcar_irq_domain_map,
};

static void gpio_rcar_parse_pdata(struct gpio_rcar_priv *p)
{
	struct gpio_rcar_config *pdata = dev_get_platdata(&p->pdev->dev);
	struct device_node *np = p->pdev->dev.of_node;
	struct of_phandle_args args;
	int ret;

	if (pdata) {
		p->config = *pdata;
	} else if (IS_ENABLED(CONFIG_OF) && np) {
		ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0,
						       &args);
		p->config.number_of_pins = ret == 0 ? args.args[2]
					 : RCAR_MAX_GPIO_PER_BANK;
		p->config.gpio_base = -1;
	}

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

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;
	const char *name = dev_name(&pdev->dev);
	int ret;

	p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
	if (!p) {
		dev_err(&pdev->dev, "failed to allocate driver data\n");
		ret = -ENOMEM;
		goto err0;
	}

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

	/* Get device configuration from DT node or platform data. */
	gpio_rcar_parse_pdata(p);

	platform_set_drvdata(pdev, p);

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

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

	p->base = devm_ioremap_nocache(&pdev->dev, io->start,
				       resource_size(io));
	if (!p->base) {
		dev_err(&pdev->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->to_irq = gpio_rcar_to_irq;
	gpio_chip->label = name;
	gpio_chip->dev = &pdev->dev;
	gpio_chip->owner = THIS_MODULE;
	gpio_chip->base = p->config.gpio_base;
	gpio_chip->ngpio = p->config.number_of_pins;

	irq_chip = &p->irq_chip;
	irq_chip->name = name;
	irq_chip->irq_mask = gpio_rcar_irq_disable;
	irq_chip->irq_unmask = gpio_rcar_irq_enable;
	irq_chip->irq_enable = gpio_rcar_irq_enable;
	irq_chip->irq_disable = gpio_rcar_irq_disable;
	irq_chip->irq_set_type = gpio_rcar_irq_set_type;
	irq_chip->flags	= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_SET_TYPE_MASKED;

	p->irq_domain = irq_domain_add_simple(pdev->dev.of_node,
					      p->config.number_of_pins,
					      p->config.irq_base,
					      &gpio_rcar_irq_domain_ops, p);
	if (!p->irq_domain) {
		ret = -ENXIO;
		dev_err(&pdev->dev, "cannot initialize irq domain\n");
		goto err1;
	}

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

	ret = gpiochip_add(gpio_chip);
	if (ret) {
		dev_err(&pdev->dev, "failed to add GPIO controller\n");
		goto err1;
	}

	dev_info(&pdev->dev, "driving %d GPIOs\n", p->config.number_of_pins);

	/* warn in case of mismatch if irq base is specified */
	if (p->config.irq_base) {
		ret = irq_find_mapping(p->irq_domain, 0);
		if (p->config.irq_base != ret)
			dev_warn(&pdev->dev, "irq base mismatch (%u/%u)\n",
				 p->config.irq_base, ret);
	}

	if (p->config.pctl_name) {
		ret = gpiochip_add_pin_range(gpio_chip, p->config.pctl_name, 0,
					     gpio_chip->base, gpio_chip->ngpio);
		if (ret < 0)
			dev_warn(&pdev->dev, "failed to add pin range\n");
	}

	return 0;

err1:
	irq_domain_remove(p->irq_domain);
err0:
	return ret;
}

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

	ret = gpiochip_remove(&p->gpio_chip);
	if (ret)
		return ret;

	irq_domain_remove(p->irq_domain);
	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id gpio_rcar_of_table[] = {
	{
		.compatible = "renesas,gpio-rcar",
	},
	{ },
};

MODULE_DEVICE_TABLE(of, gpio_rcar_of_table);
#endif

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");