xref: /openbmc/linux/drivers/gpio/gpio-bcm-kona.c (revision 82e6fdd6)
1 /*
2  * Broadcom Kona GPIO Driver
3  *
4  * Author: Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>
5  * Copyright (C) 2012-2014 Broadcom Corporation
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation version 2.
10  *
11  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12  * kind, whether express or implied; without even the implied warranty
13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/bitops.h>
18 #include <linux/err.h>
19 #include <linux/io.h>
20 #include <linux/gpio/driver.h>
21 #include <linux/of_device.h>
22 #include <linux/of_irq.h>
23 #include <linux/init.h>
24 #include <linux/irqdomain.h>
25 #include <linux/irqchip/chained_irq.h>
26 
27 #define BCM_GPIO_PASSWD				0x00a5a501
28 #define GPIO_PER_BANK				32
29 #define GPIO_MAX_BANK_NUM			8
30 
31 #define GPIO_BANK(gpio)				((gpio) >> 5)
32 #define GPIO_BIT(gpio)				((gpio) & (GPIO_PER_BANK - 1))
33 
34 /* There is a GPIO control register for each GPIO */
35 #define GPIO_CONTROL(gpio)			(0x00000100 + ((gpio) << 2))
36 
37 /* The remaining registers are per GPIO bank */
38 #define GPIO_OUT_STATUS(bank)			(0x00000000 + ((bank) << 2))
39 #define GPIO_IN_STATUS(bank)			(0x00000020 + ((bank) << 2))
40 #define GPIO_OUT_SET(bank)			(0x00000040 + ((bank) << 2))
41 #define GPIO_OUT_CLEAR(bank)			(0x00000060 + ((bank) << 2))
42 #define GPIO_INT_STATUS(bank)			(0x00000080 + ((bank) << 2))
43 #define GPIO_INT_MASK(bank)			(0x000000a0 + ((bank) << 2))
44 #define GPIO_INT_MSKCLR(bank)			(0x000000c0 + ((bank) << 2))
45 #define GPIO_PWD_STATUS(bank)			(0x00000500 + ((bank) << 2))
46 
47 #define GPIO_GPPWR_OFFSET			0x00000520
48 
49 #define GPIO_GPCTR0_DBR_SHIFT			5
50 #define GPIO_GPCTR0_DBR_MASK			0x000001e0
51 
52 #define GPIO_GPCTR0_ITR_SHIFT			3
53 #define GPIO_GPCTR0_ITR_MASK			0x00000018
54 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE		0x00000001
55 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE	0x00000002
56 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE		0x00000003
57 
58 #define GPIO_GPCTR0_IOTR_MASK			0x00000001
59 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT		0x00000000
60 #define GPIO_GPCTR0_IOTR_CMD_INPUT		0x00000001
61 
62 #define GPIO_GPCTR0_DB_ENABLE_MASK		0x00000100
63 
64 #define LOCK_CODE				0xffffffff
65 #define UNLOCK_CODE				0x00000000
66 
67 struct bcm_kona_gpio {
68 	void __iomem *reg_base;
69 	int num_bank;
70 	raw_spinlock_t lock;
71 	struct gpio_chip gpio_chip;
72 	struct irq_domain *irq_domain;
73 	struct bcm_kona_gpio_bank *banks;
74 	struct platform_device *pdev;
75 };
76 
77 struct bcm_kona_gpio_bank {
78 	int id;
79 	int irq;
80 	/* Used in the interrupt handler */
81 	struct bcm_kona_gpio *kona_gpio;
82 };
83 
84 static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
85 						int bank_id, u32 lockcode)
86 {
87 	writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
88 	writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
89 }
90 
91 static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
92 					unsigned gpio)
93 {
94 	u32 val;
95 	unsigned long flags;
96 	int bank_id = GPIO_BANK(gpio);
97 
98 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
99 
100 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
101 	val |= BIT(gpio);
102 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
103 
104 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
105 }
106 
107 static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
108 					unsigned gpio)
109 {
110 	u32 val;
111 	unsigned long flags;
112 	int bank_id = GPIO_BANK(gpio);
113 
114 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
115 
116 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
117 	val &= ~BIT(gpio);
118 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
119 
120 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
121 }
122 
123 static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
124 {
125 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
126 	void __iomem *reg_base = kona_gpio->reg_base;
127 	u32 val;
128 
129 	val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
130 	return !!val;
131 }
132 
133 static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
134 {
135 	struct bcm_kona_gpio *kona_gpio;
136 	void __iomem *reg_base;
137 	int bank_id = GPIO_BANK(gpio);
138 	int bit = GPIO_BIT(gpio);
139 	u32 val, reg_offset;
140 	unsigned long flags;
141 
142 	kona_gpio = gpiochip_get_data(chip);
143 	reg_base = kona_gpio->reg_base;
144 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
145 
146 	/* this function only applies to output pin */
147 	if (bcm_kona_gpio_get_dir(chip, gpio) == 1)
148 		goto out;
149 
150 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
151 
152 	val = readl(reg_base + reg_offset);
153 	val |= BIT(bit);
154 	writel(val, reg_base + reg_offset);
155 
156 out:
157 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
158 }
159 
160 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
161 {
162 	struct bcm_kona_gpio *kona_gpio;
163 	void __iomem *reg_base;
164 	int bank_id = GPIO_BANK(gpio);
165 	int bit = GPIO_BIT(gpio);
166 	u32 val, reg_offset;
167 	unsigned long flags;
168 
169 	kona_gpio = gpiochip_get_data(chip);
170 	reg_base = kona_gpio->reg_base;
171 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
172 
173 	if (bcm_kona_gpio_get_dir(chip, gpio) == 1)
174 		reg_offset = GPIO_IN_STATUS(bank_id);
175 	else
176 		reg_offset = GPIO_OUT_STATUS(bank_id);
177 
178 	/* read the GPIO bank status */
179 	val = readl(reg_base + reg_offset);
180 
181 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
182 
183 	/* return the specified bit status */
184 	return !!(val & BIT(bit));
185 }
186 
187 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
188 {
189 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
190 
191 	bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
192 	return 0;
193 }
194 
195 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
196 {
197 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
198 
199 	bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
200 }
201 
202 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
203 {
204 	struct bcm_kona_gpio *kona_gpio;
205 	void __iomem *reg_base;
206 	u32 val;
207 	unsigned long flags;
208 
209 	kona_gpio = gpiochip_get_data(chip);
210 	reg_base = kona_gpio->reg_base;
211 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
212 
213 	val = readl(reg_base + GPIO_CONTROL(gpio));
214 	val &= ~GPIO_GPCTR0_IOTR_MASK;
215 	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
216 	writel(val, reg_base + GPIO_CONTROL(gpio));
217 
218 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
219 
220 	return 0;
221 }
222 
223 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
224 					  unsigned gpio, int value)
225 {
226 	struct bcm_kona_gpio *kona_gpio;
227 	void __iomem *reg_base;
228 	int bank_id = GPIO_BANK(gpio);
229 	int bit = GPIO_BIT(gpio);
230 	u32 val, reg_offset;
231 	unsigned long flags;
232 
233 	kona_gpio = gpiochip_get_data(chip);
234 	reg_base = kona_gpio->reg_base;
235 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
236 
237 	val = readl(reg_base + GPIO_CONTROL(gpio));
238 	val &= ~GPIO_GPCTR0_IOTR_MASK;
239 	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
240 	writel(val, reg_base + GPIO_CONTROL(gpio));
241 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
242 
243 	val = readl(reg_base + reg_offset);
244 	val |= BIT(bit);
245 	writel(val, reg_base + reg_offset);
246 
247 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
248 
249 	return 0;
250 }
251 
252 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
253 {
254 	struct bcm_kona_gpio *kona_gpio;
255 
256 	kona_gpio = gpiochip_get_data(chip);
257 	if (gpio >= kona_gpio->gpio_chip.ngpio)
258 		return -ENXIO;
259 	return irq_create_mapping(kona_gpio->irq_domain, gpio);
260 }
261 
262 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
263 				      unsigned debounce)
264 {
265 	struct bcm_kona_gpio *kona_gpio;
266 	void __iomem *reg_base;
267 	u32 val, res;
268 	unsigned long flags;
269 
270 	kona_gpio = gpiochip_get_data(chip);
271 	reg_base = kona_gpio->reg_base;
272 	/* debounce must be 1-128ms (or 0) */
273 	if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
274 		dev_err(chip->parent, "Debounce value %u not in range\n",
275 			debounce);
276 		return -EINVAL;
277 	}
278 
279 	/* calculate debounce bit value */
280 	if (debounce != 0) {
281 		/* Convert to ms */
282 		debounce /= 1000;
283 		/* find the MSB */
284 		res = fls(debounce) - 1;
285 		/* Check if MSB-1 is set (round up or down) */
286 		if (res > 0 && (debounce & BIT(res - 1)))
287 			res++;
288 	}
289 
290 	/* spin lock for read-modify-write of the GPIO register */
291 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
292 
293 	val = readl(reg_base + GPIO_CONTROL(gpio));
294 	val &= ~GPIO_GPCTR0_DBR_MASK;
295 
296 	if (debounce == 0) {
297 		/* disable debounce */
298 		val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
299 	} else {
300 		val |= GPIO_GPCTR0_DB_ENABLE_MASK |
301 		    (res << GPIO_GPCTR0_DBR_SHIFT);
302 	}
303 
304 	writel(val, reg_base + GPIO_CONTROL(gpio));
305 
306 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
307 
308 	return 0;
309 }
310 
311 static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
312 				    unsigned long config)
313 {
314 	u32 debounce;
315 
316 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
317 		return -ENOTSUPP;
318 
319 	debounce = pinconf_to_config_argument(config);
320 	return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
321 }
322 
323 static const struct gpio_chip template_chip = {
324 	.label = "bcm-kona-gpio",
325 	.owner = THIS_MODULE,
326 	.request = bcm_kona_gpio_request,
327 	.free = bcm_kona_gpio_free,
328 	.get_direction = bcm_kona_gpio_get_dir,
329 	.direction_input = bcm_kona_gpio_direction_input,
330 	.get = bcm_kona_gpio_get,
331 	.direction_output = bcm_kona_gpio_direction_output,
332 	.set = bcm_kona_gpio_set,
333 	.set_config = bcm_kona_gpio_set_config,
334 	.to_irq = bcm_kona_gpio_to_irq,
335 	.base = 0,
336 };
337 
338 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
339 {
340 	struct bcm_kona_gpio *kona_gpio;
341 	void __iomem *reg_base;
342 	unsigned gpio = d->hwirq;
343 	int bank_id = GPIO_BANK(gpio);
344 	int bit = GPIO_BIT(gpio);
345 	u32 val;
346 	unsigned long flags;
347 
348 	kona_gpio = irq_data_get_irq_chip_data(d);
349 	reg_base = kona_gpio->reg_base;
350 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
351 
352 	val = readl(reg_base + GPIO_INT_STATUS(bank_id));
353 	val |= BIT(bit);
354 	writel(val, reg_base + GPIO_INT_STATUS(bank_id));
355 
356 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
357 }
358 
359 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
360 {
361 	struct bcm_kona_gpio *kona_gpio;
362 	void __iomem *reg_base;
363 	unsigned gpio = d->hwirq;
364 	int bank_id = GPIO_BANK(gpio);
365 	int bit = GPIO_BIT(gpio);
366 	u32 val;
367 	unsigned long flags;
368 
369 	kona_gpio = irq_data_get_irq_chip_data(d);
370 	reg_base = kona_gpio->reg_base;
371 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
372 
373 	val = readl(reg_base + GPIO_INT_MASK(bank_id));
374 	val |= BIT(bit);
375 	writel(val, reg_base + GPIO_INT_MASK(bank_id));
376 
377 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
378 }
379 
380 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
381 {
382 	struct bcm_kona_gpio *kona_gpio;
383 	void __iomem *reg_base;
384 	unsigned gpio = d->hwirq;
385 	int bank_id = GPIO_BANK(gpio);
386 	int bit = GPIO_BIT(gpio);
387 	u32 val;
388 	unsigned long flags;
389 
390 	kona_gpio = irq_data_get_irq_chip_data(d);
391 	reg_base = kona_gpio->reg_base;
392 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
393 
394 	val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
395 	val |= BIT(bit);
396 	writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
397 
398 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
399 }
400 
401 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
402 {
403 	struct bcm_kona_gpio *kona_gpio;
404 	void __iomem *reg_base;
405 	unsigned gpio = d->hwirq;
406 	u32 lvl_type;
407 	u32 val;
408 	unsigned long flags;
409 
410 	kona_gpio = irq_data_get_irq_chip_data(d);
411 	reg_base = kona_gpio->reg_base;
412 	switch (type & IRQ_TYPE_SENSE_MASK) {
413 	case IRQ_TYPE_EDGE_RISING:
414 		lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
415 		break;
416 
417 	case IRQ_TYPE_EDGE_FALLING:
418 		lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
419 		break;
420 
421 	case IRQ_TYPE_EDGE_BOTH:
422 		lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
423 		break;
424 
425 	case IRQ_TYPE_LEVEL_HIGH:
426 	case IRQ_TYPE_LEVEL_LOW:
427 		/* BCM GPIO doesn't support level triggering */
428 	default:
429 		dev_err(kona_gpio->gpio_chip.parent,
430 			"Invalid BCM GPIO irq type 0x%x\n", type);
431 		return -EINVAL;
432 	}
433 
434 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
435 
436 	val = readl(reg_base + GPIO_CONTROL(gpio));
437 	val &= ~GPIO_GPCTR0_ITR_MASK;
438 	val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
439 	writel(val, reg_base + GPIO_CONTROL(gpio));
440 
441 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
442 
443 	return 0;
444 }
445 
446 static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
447 {
448 	void __iomem *reg_base;
449 	int bit, bank_id;
450 	unsigned long sta;
451 	struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
452 	struct irq_chip *chip = irq_desc_get_chip(desc);
453 
454 	chained_irq_enter(chip, desc);
455 
456 	/*
457 	 * For bank interrupts, we can't use chip_data to store the kona_gpio
458 	 * pointer, since GIC needs it for its own purposes. Therefore, we get
459 	 * our pointer from the bank structure.
460 	 */
461 	reg_base = bank->kona_gpio->reg_base;
462 	bank_id = bank->id;
463 
464 	while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
465 		    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
466 		for_each_set_bit(bit, &sta, 32) {
467 			int hwirq = GPIO_PER_BANK * bank_id + bit;
468 			int child_irq =
469 				irq_find_mapping(bank->kona_gpio->irq_domain,
470 						 hwirq);
471 			/*
472 			 * Clear interrupt before handler is called so we don't
473 			 * miss any interrupt occurred during executing them.
474 			 */
475 			writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
476 			       BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
477 			/* Invoke interrupt handler */
478 			generic_handle_irq(child_irq);
479 		}
480 	}
481 
482 	chained_irq_exit(chip, desc);
483 }
484 
485 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
486 {
487 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
488 
489 	if (gpiochip_lock_as_irq(&kona_gpio->gpio_chip, d->hwirq)) {
490 		dev_err(kona_gpio->gpio_chip.parent,
491 			"unable to lock HW IRQ %lu for IRQ\n",
492 			d->hwirq);
493 		return -EINVAL;
494 	}
495 	return 0;
496 }
497 
498 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
499 {
500 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
501 
502 	gpiochip_unlock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
503 }
504 
505 static struct irq_chip bcm_gpio_irq_chip = {
506 	.name = "bcm-kona-gpio",
507 	.irq_ack = bcm_kona_gpio_irq_ack,
508 	.irq_mask = bcm_kona_gpio_irq_mask,
509 	.irq_unmask = bcm_kona_gpio_irq_unmask,
510 	.irq_set_type = bcm_kona_gpio_irq_set_type,
511 	.irq_request_resources = bcm_kona_gpio_irq_reqres,
512 	.irq_release_resources = bcm_kona_gpio_irq_relres,
513 };
514 
515 static struct of_device_id const bcm_kona_gpio_of_match[] = {
516 	{ .compatible = "brcm,kona-gpio" },
517 	{}
518 };
519 
520 /*
521  * This lock class tells lockdep that GPIO irqs are in a different
522  * category than their parents, so it won't report false recursion.
523  */
524 static struct lock_class_key gpio_lock_class;
525 static struct lock_class_key gpio_request_class;
526 
527 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
528 				 irq_hw_number_t hwirq)
529 {
530 	int ret;
531 
532 	ret = irq_set_chip_data(irq, d->host_data);
533 	if (ret < 0)
534 		return ret;
535 	irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
536 	irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
537 	irq_set_noprobe(irq);
538 
539 	return 0;
540 }
541 
542 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
543 {
544 	irq_set_chip_and_handler(irq, NULL, NULL);
545 	irq_set_chip_data(irq, NULL);
546 }
547 
548 static const struct irq_domain_ops bcm_kona_irq_ops = {
549 	.map = bcm_kona_gpio_irq_map,
550 	.unmap = bcm_kona_gpio_irq_unmap,
551 	.xlate = irq_domain_xlate_twocell,
552 };
553 
554 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
555 {
556 	void __iomem *reg_base;
557 	int i;
558 
559 	reg_base = kona_gpio->reg_base;
560 	/* disable interrupts and clear status */
561 	for (i = 0; i < kona_gpio->num_bank; i++) {
562 		/* Unlock the entire bank first */
563 		bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
564 		writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
565 		writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
566 		/* Now re-lock the bank */
567 		bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
568 	}
569 }
570 
571 static int bcm_kona_gpio_probe(struct platform_device *pdev)
572 {
573 	struct device *dev = &pdev->dev;
574 	const struct of_device_id *match;
575 	struct resource *res;
576 	struct bcm_kona_gpio_bank *bank;
577 	struct bcm_kona_gpio *kona_gpio;
578 	struct gpio_chip *chip;
579 	int ret;
580 	int i;
581 
582 	match = of_match_device(bcm_kona_gpio_of_match, dev);
583 	if (!match) {
584 		dev_err(dev, "Failed to find gpio controller\n");
585 		return -ENODEV;
586 	}
587 
588 	kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
589 	if (!kona_gpio)
590 		return -ENOMEM;
591 
592 	kona_gpio->gpio_chip = template_chip;
593 	chip = &kona_gpio->gpio_chip;
594 	kona_gpio->num_bank = of_irq_count(dev->of_node);
595 	if (kona_gpio->num_bank == 0) {
596 		dev_err(dev, "Couldn't determine # GPIO banks\n");
597 		return -ENOENT;
598 	}
599 	if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
600 		dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
601 			GPIO_MAX_BANK_NUM);
602 		return -ENXIO;
603 	}
604 	kona_gpio->banks = devm_kzalloc(dev,
605 					kona_gpio->num_bank *
606 					sizeof(*kona_gpio->banks), GFP_KERNEL);
607 	if (!kona_gpio->banks)
608 		return -ENOMEM;
609 
610 	kona_gpio->pdev = pdev;
611 	platform_set_drvdata(pdev, kona_gpio);
612 	chip->of_node = dev->of_node;
613 	chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
614 
615 	kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
616 						      chip->ngpio,
617 						      &bcm_kona_irq_ops,
618 						      kona_gpio);
619 	if (!kona_gpio->irq_domain) {
620 		dev_err(dev, "Couldn't allocate IRQ domain\n");
621 		return -ENXIO;
622 	}
623 
624 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
625 	kona_gpio->reg_base = devm_ioremap_resource(dev, res);
626 	if (IS_ERR(kona_gpio->reg_base)) {
627 		ret = -ENXIO;
628 		goto err_irq_domain;
629 	}
630 
631 	for (i = 0; i < kona_gpio->num_bank; i++) {
632 		bank = &kona_gpio->banks[i];
633 		bank->id = i;
634 		bank->irq = platform_get_irq(pdev, i);
635 		bank->kona_gpio = kona_gpio;
636 		if (bank->irq < 0) {
637 			dev_err(dev, "Couldn't get IRQ for bank %d", i);
638 			ret = -ENOENT;
639 			goto err_irq_domain;
640 		}
641 	}
642 
643 	dev_info(&pdev->dev, "Setting up Kona GPIO\n");
644 
645 	bcm_kona_gpio_reset(kona_gpio);
646 
647 	ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
648 	if (ret < 0) {
649 		dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
650 		goto err_irq_domain;
651 	}
652 	for (i = 0; i < kona_gpio->num_bank; i++) {
653 		bank = &kona_gpio->banks[i];
654 		irq_set_chained_handler_and_data(bank->irq,
655 						 bcm_kona_gpio_irq_handler,
656 						 bank);
657 	}
658 
659 	raw_spin_lock_init(&kona_gpio->lock);
660 
661 	return 0;
662 
663 err_irq_domain:
664 	irq_domain_remove(kona_gpio->irq_domain);
665 
666 	return ret;
667 }
668 
669 static struct platform_driver bcm_kona_gpio_driver = {
670 	.driver = {
671 			.name = "bcm-kona-gpio",
672 			.of_match_table = bcm_kona_gpio_of_match,
673 	},
674 	.probe = bcm_kona_gpio_probe,
675 };
676 builtin_platform_driver(bcm_kona_gpio_driver);
677