aboutsummaryrefslogtreecommitdiff
path: root/drivers/gpio/gpio-tegra.c
blob: 027e5f47dd28738f04e6347f1807c6b28b34e618 (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
/*
 * arch/arm/mach-tegra/gpio.c
 *
 * Copyright (c) 2010 Google, Inc
 *
 * Author:
 *	Erik Gilling <konkers@google.com>
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * 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/init.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/irqdomain.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm.h>

#define GPIO_BANK(x)		((x) >> 5)
#define GPIO_PORT(x)		(((x) >> 3) & 0x3)
#define GPIO_BIT(x)		((x) & 0x7)

#define GPIO_REG(x)		(GPIO_BANK(x) * tegra_gpio_bank_stride + \
					GPIO_PORT(x) * 4)

#define GPIO_CNF(x)		(GPIO_REG(x) + 0x00)
#define GPIO_OE(x)		(GPIO_REG(x) + 0x10)
#define GPIO_OUT(x)		(GPIO_REG(x) + 0X20)
#define GPIO_IN(x)		(GPIO_REG(x) + 0x30)
#define GPIO_INT_STA(x)		(GPIO_REG(x) + 0x40)
#define GPIO_INT_ENB(x)		(GPIO_REG(x) + 0x50)
#define GPIO_INT_LVL(x)		(GPIO_REG(x) + 0x60)
#define GPIO_INT_CLR(x)		(GPIO_REG(x) + 0x70)

#define GPIO_MSK_CNF(x)		(GPIO_REG(x) + tegra_gpio_upper_offset + 0x00)
#define GPIO_MSK_OE(x)		(GPIO_REG(x) + tegra_gpio_upper_offset + 0x10)
#define GPIO_MSK_OUT(x)		(GPIO_REG(x) + tegra_gpio_upper_offset + 0X20)
#define GPIO_MSK_INT_STA(x)	(GPIO_REG(x) + tegra_gpio_upper_offset + 0x40)
#define GPIO_MSK_INT_ENB(x)	(GPIO_REG(x) + tegra_gpio_upper_offset + 0x50)
#define GPIO_MSK_INT_LVL(x)	(GPIO_REG(x) + tegra_gpio_upper_offset + 0x60)

#define GPIO_INT_LVL_MASK		0x010101
#define GPIO_INT_LVL_EDGE_RISING	0x000101
#define GPIO_INT_LVL_EDGE_FALLING	0x000100
#define GPIO_INT_LVL_EDGE_BOTH		0x010100
#define GPIO_INT_LVL_LEVEL_HIGH		0x000001
#define GPIO_INT_LVL_LEVEL_LOW		0x000000

struct tegra_gpio_bank {
	int bank;
	int irq;
	spinlock_t lvl_lock[4];
#ifdef CONFIG_PM_SLEEP
	u32 cnf[4];
	u32 out[4];
	u32 oe[4];
	u32 int_enb[4];
	u32 int_lvl[4];
	u32 wake_enb[4];
#endif
};

static struct device *dev;
static struct irq_domain *irq_domain;
static void __iomem *regs;
static u32 tegra_gpio_bank_count;
static u32 tegra_gpio_bank_stride;
static u32 tegra_gpio_upper_offset;
static struct tegra_gpio_bank *tegra_gpio_banks;

static inline void tegra_gpio_writel(u32 val, u32 reg)
{
	__raw_writel(val, regs + reg);
}

static inline u32 tegra_gpio_readl(u32 reg)
{
	return __raw_readl(regs + reg);
}

static int tegra_gpio_compose(int bank, int port, int bit)
{
	return (bank << 5) | ((port & 0x3) << 3) | (bit & 0x7);
}

static void tegra_gpio_mask_write(u32 reg, int gpio, int value)
{
	u32 val;

	val = 0x100 << GPIO_BIT(gpio);
	if (value)
		val |= 1 << GPIO_BIT(gpio);
	tegra_gpio_writel(val, reg);
}

static void tegra_gpio_enable(int gpio)
{
	tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1);
}

static void tegra_gpio_disable(int gpio)
{
	tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0);
}

static int tegra_gpio_request(struct gpio_chip *chip, unsigned offset)
{
	return pinctrl_request_gpio(offset);
}

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

static void tegra_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
	tegra_gpio_mask_write(GPIO_MSK_OUT(offset), offset, value);
}

static int tegra_gpio_get(struct gpio_chip *chip, unsigned offset)
{
	/* If gpio is in output mode then read from the out value */
	if ((tegra_gpio_readl(GPIO_OE(offset)) >> GPIO_BIT(offset)) & 1)
		return (tegra_gpio_readl(GPIO_OUT(offset)) >>
				GPIO_BIT(offset)) & 0x1;

	return (tegra_gpio_readl(GPIO_IN(offset)) >> GPIO_BIT(offset)) & 0x1;
}

static int tegra_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
	tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 0);
	tegra_gpio_enable(offset);
	return 0;
}

static int tegra_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
					int value)
{
	tegra_gpio_set(chip, offset, value);
	tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 1);
	tegra_gpio_enable(offset);
	return 0;
}

static int tegra_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
	return irq_find_mapping(irq_domain, offset);
}

static struct gpio_chip tegra_gpio_chip = {
	.label			= "tegra-gpio",
	.request		= tegra_gpio_request,
	.free			= tegra_gpio_free,
	.direction_input	= tegra_gpio_direction_input,
	.get			= tegra_gpio_get,
	.direction_output	= tegra_gpio_direction_output,
	.set			= tegra_gpio_set,
	.to_irq			= tegra_gpio_to_irq,
	.base			= 0,
};

static void tegra_gpio_irq_ack(struct irq_data *d)
{
	int gpio = d->hwirq;

	tegra_gpio_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio));
}

static void tegra_gpio_irq_mask(struct irq_data *d)
{
	int gpio = d->hwirq;

	tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0);
}

static void tegra_gpio_irq_unmask(struct irq_data *d)
{
	int gpio = d->hwirq;

	tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 1);
}

static int tegra_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
	int gpio = d->hwirq;
	struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
	int port = GPIO_PORT(gpio);
	int lvl_type;
	int val;
	unsigned long flags;
	int ret;

	switch (type & IRQ_TYPE_SENSE_MASK) {
	case IRQ_TYPE_EDGE_RISING:
		lvl_type = GPIO_INT_LVL_EDGE_RISING;
		break;

	case IRQ_TYPE_EDGE_FALLING:
		lvl_type = GPIO_INT_LVL_EDGE_FALLING;
		break;

	case IRQ_TYPE_EDGE_BOTH:
		lvl_type = GPIO_INT_LVL_EDGE_BOTH;
		break;

	case IRQ_TYPE_LEVEL_HIGH:
		lvl_type = GPIO_INT_LVL_LEVEL_HIGH;
		break;

	case IRQ_TYPE_LEVEL_LOW:
		lvl_type = GPIO_INT_LVL_LEVEL_LOW;
		break;

	default:
		return -EINVAL;
	}

	ret = gpiochip_lock_as_irq(&tegra_gpio_chip, gpio);
	if (ret) {
		dev_err(dev, "unable to lock Tegra GPIO %d as IRQ\n", gpio);
		return ret;
	}

	spin_lock_irqsave(&bank->lvl_lock[port], flags);

	val = tegra_gpio_readl(GPIO_INT_LVL(gpio));
	val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio));
	val |= lvl_type << GPIO_BIT(gpio);
	tegra_gpio_writel(val, GPIO_INT_LVL(gpio));

	spin_unlock_irqrestore(&bank->lvl_lock[port], flags);

	tegra_gpio_mask_write(GPIO_MSK_OE(gpio), gpio, 0);
	tegra_gpio_enable(gpio);

	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
		irq_set_handler_locked(d, handle_level_irq);
	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
		irq_set_handler_locked(d, handle_edge_irq);

	return 0;
}

static void tegra_gpio_irq_shutdown(struct irq_data *d)
{
	int gpio = d->hwirq;

	gpiochip_unlock_as_irq(&tegra_gpio_chip, gpio);
}

static void tegra_gpio_irq_handler(struct irq_desc *desc)
{
	int port;
	int pin;
	int unmasked = 0;
	struct irq_chip *chip = irq_desc_get_chip(desc);
	struct tegra_gpio_bank *bank = irq_desc_get_handler_data(desc);

	chained_irq_enter(chip, desc);

	for (port = 0; port < 4; port++) {
		int gpio = tegra_gpio_compose(bank->bank, port, 0);
		unsigned long sta = tegra_gpio_readl(GPIO_INT_STA(gpio)) &
			tegra_gpio_readl(GPIO_INT_ENB(gpio));
		u32 lvl = tegra_gpio_readl(GPIO_INT_LVL(gpio));

		for_each_set_bit(pin, &sta, 8) {
			tegra_gpio_writel(1 << pin, GPIO_INT_CLR(gpio));

			/* if gpio is edge triggered, clear condition
			 * before executing the handler so that we don't
			 * miss edges
			 */
			if (lvl & (0x100 << pin)) {
				unmasked = 1;
				chained_irq_exit(chip, desc);
			}

			generic_handle_irq(gpio_to_irq(gpio + pin));
		}
	}

	if (!unmasked)
		chained_irq_exit(chip, desc);

}

#ifdef CONFIG_PM_SLEEP
static int tegra_gpio_resume(struct device *dev)
{
	unsigned long flags;
	int b;
	int p;

	local_irq_save(flags);

	for (b = 0; b < tegra_gpio_bank_count; b++) {
		struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];

		for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
			unsigned int gpio = (b<<5) | (p<<3);
			tegra_gpio_writel(bank->cnf[p], GPIO_CNF(gpio));
			tegra_gpio_writel(bank->out[p], GPIO_OUT(gpio));
			tegra_gpio_writel(bank->oe[p], GPIO_OE(gpio));
			tegra_gpio_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio));
			tegra_gpio_writel(bank->int_enb[p], GPIO_INT_ENB(gpio));
		}
	}

	local_irq_restore(flags);
	return 0;
}

static int tegra_gpio_suspend(struct device *dev)
{
	unsigned long flags;
	int b;
	int p;

	local_irq_save(flags);
	for (b = 0; b < tegra_gpio_bank_count; b++) {
		struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];

		for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
			unsigned int gpio = (b<<5) | (p<<3);
			bank->cnf[p] = tegra_gpio_readl(GPIO_CNF(gpio));
			bank->out[p] = tegra_gpio_readl(GPIO_OUT(gpio));
			bank->oe[p] = tegra_gpio_readl(GPIO_OE(gpio));
			bank->int_enb[p] = tegra_gpio_readl(GPIO_INT_ENB(gpio));
			bank->int_lvl[p] = tegra_gpio_readl(GPIO_INT_LVL(gpio));

			/* Enable gpio irq for wake up source */
			tegra_gpio_writel(bank->wake_enb[p],
					  GPIO_INT_ENB(gpio));
		}
	}
	local_irq_restore(flags);
	return 0;
}

static int tegra_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
{
	struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
	int gpio = d->hwirq;
	u32 port, bit, mask;

	port = GPIO_PORT(gpio);
	bit = GPIO_BIT(gpio);
	mask = BIT(bit);

	if (enable)
		bank->wake_enb[port] |= mask;
	else
		bank->wake_enb[port] &= ~mask;

	return irq_set_irq_wake(bank->irq, enable);
}
#endif

static struct irq_chip tegra_gpio_irq_chip = {
	.name		= "GPIO",
	.irq_ack	= tegra_gpio_irq_ack,
	.irq_mask	= tegra_gpio_irq_mask,
	.irq_unmask	= tegra_gpio_irq_unmask,
	.irq_set_type	= tegra_gpio_irq_set_type,
	.irq_shutdown	= tegra_gpio_irq_shutdown,
#ifdef CONFIG_PM_SLEEP
	.irq_set_wake	= tegra_gpio_irq_set_wake,
#endif
};

static const struct dev_pm_ops tegra_gpio_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(tegra_gpio_suspend, tegra_gpio_resume)
};

struct tegra_gpio_soc_config {
	u32 bank_stride;
	u32 upper_offset;
};

static struct tegra_gpio_soc_config tegra20_gpio_config = {
	.bank_stride = 0x80,
	.upper_offset = 0x800,
};

static struct tegra_gpio_soc_config tegra30_gpio_config = {
	.bank_stride = 0x100,
	.upper_offset = 0x80,
};

static const struct of_device_id tegra_gpio_of_match[] = {
	{ .compatible = "nvidia,tegra30-gpio", .data = &tegra30_gpio_config },
	{ .compatible = "nvidia,tegra20-gpio", .data = &tegra20_gpio_config },
	{ },
};

/* This lock class tells lockdep that GPIO irqs are in a different
 * category than their parents, so it won't report false recursion.
 */
static struct lock_class_key gpio_lock_class;

static int tegra_gpio_probe(struct platform_device *pdev)
{
	const struct of_device_id *match;
	struct tegra_gpio_soc_config *config;
	struct resource *res;
	struct tegra_gpio_bank *bank;
	int ret;
	int gpio;
	int i;
	int j;

	dev = &pdev->dev;

	match = of_match_device(tegra_gpio_of_match, &pdev->dev);
	if (!match) {
		dev_err(&pdev->dev, "Error: No device match found\n");
		return -ENODEV;
	}
	config = (struct tegra_gpio_soc_config *)match->data;

	tegra_gpio_bank_stride = config->bank_stride;
	tegra_gpio_upper_offset = config->upper_offset;

	for (;;) {
		res = platform_get_resource(pdev, IORESOURCE_IRQ, tegra_gpio_bank_count);
		if (!res)
			break;
		tegra_gpio_bank_count++;
	}
	if (!tegra_gpio_bank_count) {
		dev_err(&pdev->dev, "Missing IRQ resource\n");
		return -ENODEV;
	}

	tegra_gpio_chip.ngpio = tegra_gpio_bank_count * 32;

	tegra_gpio_banks = devm_kzalloc(&pdev->dev,
			tegra_gpio_bank_count * sizeof(*tegra_gpio_banks),
			GFP_KERNEL);
	if (!tegra_gpio_banks)
		return -ENODEV;

	irq_domain = irq_domain_add_linear(pdev->dev.of_node,
					   tegra_gpio_chip.ngpio,
					   &irq_domain_simple_ops, NULL);
	if (!irq_domain)
		return -ENODEV;

	for (i = 0; i < tegra_gpio_bank_count; i++) {
		res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
		if (!res) {
			dev_err(&pdev->dev, "Missing IRQ resource\n");
			return -ENODEV;
		}

		bank = &tegra_gpio_banks[i];
		bank->bank = i;
		bank->irq = res->start;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(regs))
		return PTR_ERR(regs);

	for (i = 0; i < tegra_gpio_bank_count; i++) {
		for (j = 0; j < 4; j++) {
			int gpio = tegra_gpio_compose(i, j, 0);
			tegra_gpio_writel(0x00, GPIO_INT_ENB(gpio));
		}
	}

	tegra_gpio_chip.of_node = pdev->dev.of_node;

	ret = gpiochip_add(&tegra_gpio_chip);
	if (ret < 0) {
		irq_domain_remove(irq_domain);
		return ret;
	}

	for (gpio = 0; gpio < tegra_gpio_chip.ngpio; gpio++) {
		int irq = irq_create_mapping(irq_domain, gpio);
		/* No validity check; all Tegra GPIOs are valid IRQs */

		bank = &tegra_gpio_banks[GPIO_BANK(gpio)];

		irq_set_lockdep_class(irq, &gpio_lock_class);
		irq_set_chip_data(irq, bank);
		irq_set_chip_and_handler(irq, &tegra_gpio_irq_chip,
					 handle_simple_irq);
	}

	for (i = 0; i < tegra_gpio_bank_count; i++) {
		bank = &tegra_gpio_banks[i];

		irq_set_chained_handler_and_data(bank->irq,
						 tegra_gpio_irq_handler, bank);

		for (j = 0; j < 4; j++)
			spin_lock_init(&bank->lvl_lock[j]);
	}

	return 0;
}

static struct platform_driver tegra_gpio_driver = {
	.driver		= {
		.name	= "tegra-gpio",
		.pm	= &tegra_gpio_pm_ops,
		.of_match_table = tegra_gpio_of_match,
	},
	.probe		= tegra_gpio_probe,
};

static int __init tegra_gpio_init(void)
{
	return platform_driver_register(&tegra_gpio_driver);
}
postcore_initcall(tegra_gpio_init);

#ifdef	CONFIG_DEBUG_FS

#include <linux/debugfs.h>
#include <linux/seq_file.h>

static int dbg_gpio_show(struct seq_file *s, void *unused)
{
	int i;
	int j;

	for (i = 0; i < tegra_gpio_bank_count; i++) {
		for (j = 0; j < 4; j++) {
			int gpio = tegra_gpio_compose(i, j, 0);
			seq_printf(s,
				"%d:%d %02x %02x %02x %02x %02x %02x %06x\n",
				i, j,
				tegra_gpio_readl(GPIO_CNF(gpio)),
				tegra_gpio_readl(GPIO_OE(gpio)),
				tegra_gpio_readl(GPIO_OUT(gpio)),
				tegra_gpio_readl(GPIO_IN(gpio)),
				tegra_gpio_readl(GPIO_INT_STA(gpio)),
				tegra_gpio_readl(GPIO_INT_ENB(gpio)),
				tegra_gpio_readl(GPIO_INT_LVL(gpio)));
		}
	}
	return 0;
}

static int dbg_gpio_open(struct inode *inode, struct file *file)
{
	return single_open(file, dbg_gpio_show, &inode->i_private);
}

static const struct file_operations debug_fops = {
	.open		= dbg_gpio_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int __init tegra_gpio_debuginit(void)
{
	(void) debugfs_create_file("tegra_gpio", S_IRUGO,
					NULL, NULL, &debug_fops);
	return 0;
}
late_initcall(tegra_gpio_debuginit);
#endif