xref: /linux/drivers/gpio/gpio-bcm-kona.c (revision 0d4bb5e45aa698f2f357b1424b842bebe13b1c8b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Broadcom Kona GPIO Driver
4  *
5  * Author: Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>
6  * Copyright (C) 2012-2014 Broadcom Corporation
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/err.h>
11 #include <linux/io.h>
12 #include <linux/gpio/driver.h>
13 #include <linux/of_device.h>
14 #include <linux/init.h>
15 #include <linux/irqdomain.h>
16 #include <linux/irqchip/chained_irq.h>
17 
18 #define BCM_GPIO_PASSWD				0x00a5a501
19 #define GPIO_PER_BANK				32
20 #define GPIO_MAX_BANK_NUM			8
21 
22 #define GPIO_BANK(gpio)				((gpio) >> 5)
23 #define GPIO_BIT(gpio)				((gpio) & (GPIO_PER_BANK - 1))
24 
25 /* There is a GPIO control register for each GPIO */
26 #define GPIO_CONTROL(gpio)			(0x00000100 + ((gpio) << 2))
27 
28 /* The remaining registers are per GPIO bank */
29 #define GPIO_OUT_STATUS(bank)			(0x00000000 + ((bank) << 2))
30 #define GPIO_IN_STATUS(bank)			(0x00000020 + ((bank) << 2))
31 #define GPIO_OUT_SET(bank)			(0x00000040 + ((bank) << 2))
32 #define GPIO_OUT_CLEAR(bank)			(0x00000060 + ((bank) << 2))
33 #define GPIO_INT_STATUS(bank)			(0x00000080 + ((bank) << 2))
34 #define GPIO_INT_MASK(bank)			(0x000000a0 + ((bank) << 2))
35 #define GPIO_INT_MSKCLR(bank)			(0x000000c0 + ((bank) << 2))
36 #define GPIO_PWD_STATUS(bank)			(0x00000500 + ((bank) << 2))
37 
38 #define GPIO_GPPWR_OFFSET			0x00000520
39 
40 #define GPIO_GPCTR0_DBR_SHIFT			5
41 #define GPIO_GPCTR0_DBR_MASK			0x000001e0
42 
43 #define GPIO_GPCTR0_ITR_SHIFT			3
44 #define GPIO_GPCTR0_ITR_MASK			0x00000018
45 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE		0x00000001
46 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE	0x00000002
47 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE		0x00000003
48 
49 #define GPIO_GPCTR0_IOTR_MASK			0x00000001
50 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT		0x00000000
51 #define GPIO_GPCTR0_IOTR_CMD_INPUT		0x00000001
52 
53 #define GPIO_GPCTR0_DB_ENABLE_MASK		0x00000100
54 
55 #define LOCK_CODE				0xffffffff
56 #define UNLOCK_CODE				0x00000000
57 
58 struct bcm_kona_gpio {
59 	void __iomem *reg_base;
60 	int num_bank;
61 	raw_spinlock_t lock;
62 	struct gpio_chip gpio_chip;
63 	struct irq_domain *irq_domain;
64 	struct bcm_kona_gpio_bank *banks;
65 	struct platform_device *pdev;
66 };
67 
68 struct bcm_kona_gpio_bank {
69 	int id;
70 	int irq;
71 	/* Used in the interrupt handler */
72 	struct bcm_kona_gpio *kona_gpio;
73 };
74 
75 static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
76 						int bank_id, u32 lockcode)
77 {
78 	writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
79 	writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
80 }
81 
82 static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
83 					unsigned gpio)
84 {
85 	u32 val;
86 	unsigned long flags;
87 	int bank_id = GPIO_BANK(gpio);
88 
89 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
90 
91 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
92 	val |= BIT(gpio);
93 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
94 
95 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
96 }
97 
98 static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
99 					unsigned gpio)
100 {
101 	u32 val;
102 	unsigned long flags;
103 	int bank_id = GPIO_BANK(gpio);
104 
105 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
106 
107 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
108 	val &= ~BIT(gpio);
109 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
110 
111 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
112 }
113 
114 static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
115 {
116 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
117 	void __iomem *reg_base = kona_gpio->reg_base;
118 	u32 val;
119 
120 	val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
121 	return val ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
122 }
123 
124 static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
125 {
126 	struct bcm_kona_gpio *kona_gpio;
127 	void __iomem *reg_base;
128 	int bank_id = GPIO_BANK(gpio);
129 	int bit = GPIO_BIT(gpio);
130 	u32 val, reg_offset;
131 	unsigned long flags;
132 
133 	kona_gpio = gpiochip_get_data(chip);
134 	reg_base = kona_gpio->reg_base;
135 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
136 
137 	/* this function only applies to output pin */
138 	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
139 		goto out;
140 
141 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
142 
143 	val = readl(reg_base + reg_offset);
144 	val |= BIT(bit);
145 	writel(val, reg_base + reg_offset);
146 
147 out:
148 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
149 }
150 
151 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
152 {
153 	struct bcm_kona_gpio *kona_gpio;
154 	void __iomem *reg_base;
155 	int bank_id = GPIO_BANK(gpio);
156 	int bit = GPIO_BIT(gpio);
157 	u32 val, reg_offset;
158 	unsigned long flags;
159 
160 	kona_gpio = gpiochip_get_data(chip);
161 	reg_base = kona_gpio->reg_base;
162 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
163 
164 	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
165 		reg_offset = GPIO_IN_STATUS(bank_id);
166 	else
167 		reg_offset = GPIO_OUT_STATUS(bank_id);
168 
169 	/* read the GPIO bank status */
170 	val = readl(reg_base + reg_offset);
171 
172 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
173 
174 	/* return the specified bit status */
175 	return !!(val & BIT(bit));
176 }
177 
178 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
179 {
180 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
181 
182 	bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
183 	return 0;
184 }
185 
186 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
187 {
188 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
189 
190 	bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
191 }
192 
193 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
194 {
195 	struct bcm_kona_gpio *kona_gpio;
196 	void __iomem *reg_base;
197 	u32 val;
198 	unsigned long flags;
199 
200 	kona_gpio = gpiochip_get_data(chip);
201 	reg_base = kona_gpio->reg_base;
202 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
203 
204 	val = readl(reg_base + GPIO_CONTROL(gpio));
205 	val &= ~GPIO_GPCTR0_IOTR_MASK;
206 	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
207 	writel(val, reg_base + GPIO_CONTROL(gpio));
208 
209 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
210 
211 	return 0;
212 }
213 
214 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
215 					  unsigned gpio, int value)
216 {
217 	struct bcm_kona_gpio *kona_gpio;
218 	void __iomem *reg_base;
219 	int bank_id = GPIO_BANK(gpio);
220 	int bit = GPIO_BIT(gpio);
221 	u32 val, reg_offset;
222 	unsigned long flags;
223 
224 	kona_gpio = gpiochip_get_data(chip);
225 	reg_base = kona_gpio->reg_base;
226 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
227 
228 	val = readl(reg_base + GPIO_CONTROL(gpio));
229 	val &= ~GPIO_GPCTR0_IOTR_MASK;
230 	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
231 	writel(val, reg_base + GPIO_CONTROL(gpio));
232 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
233 
234 	val = readl(reg_base + reg_offset);
235 	val |= BIT(bit);
236 	writel(val, reg_base + reg_offset);
237 
238 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
239 
240 	return 0;
241 }
242 
243 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
244 {
245 	struct bcm_kona_gpio *kona_gpio;
246 
247 	kona_gpio = gpiochip_get_data(chip);
248 	if (gpio >= kona_gpio->gpio_chip.ngpio)
249 		return -ENXIO;
250 	return irq_create_mapping(kona_gpio->irq_domain, gpio);
251 }
252 
253 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
254 				      unsigned debounce)
255 {
256 	struct bcm_kona_gpio *kona_gpio;
257 	void __iomem *reg_base;
258 	u32 val, res;
259 	unsigned long flags;
260 
261 	kona_gpio = gpiochip_get_data(chip);
262 	reg_base = kona_gpio->reg_base;
263 	/* debounce must be 1-128ms (or 0) */
264 	if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
265 		dev_err(chip->parent, "Debounce value %u not in range\n",
266 			debounce);
267 		return -EINVAL;
268 	}
269 
270 	/* calculate debounce bit value */
271 	if (debounce != 0) {
272 		/* Convert to ms */
273 		debounce /= 1000;
274 		/* find the MSB */
275 		res = fls(debounce) - 1;
276 		/* Check if MSB-1 is set (round up or down) */
277 		if (res > 0 && (debounce & BIT(res - 1)))
278 			res++;
279 	}
280 
281 	/* spin lock for read-modify-write of the GPIO register */
282 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
283 
284 	val = readl(reg_base + GPIO_CONTROL(gpio));
285 	val &= ~GPIO_GPCTR0_DBR_MASK;
286 
287 	if (debounce == 0) {
288 		/* disable debounce */
289 		val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
290 	} else {
291 		val |= GPIO_GPCTR0_DB_ENABLE_MASK |
292 		    (res << GPIO_GPCTR0_DBR_SHIFT);
293 	}
294 
295 	writel(val, reg_base + GPIO_CONTROL(gpio));
296 
297 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
298 
299 	return 0;
300 }
301 
302 static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
303 				    unsigned long config)
304 {
305 	u32 debounce;
306 
307 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
308 		return -ENOTSUPP;
309 
310 	debounce = pinconf_to_config_argument(config);
311 	return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
312 }
313 
314 static const struct gpio_chip template_chip = {
315 	.label = "bcm-kona-gpio",
316 	.owner = THIS_MODULE,
317 	.request = bcm_kona_gpio_request,
318 	.free = bcm_kona_gpio_free,
319 	.get_direction = bcm_kona_gpio_get_dir,
320 	.direction_input = bcm_kona_gpio_direction_input,
321 	.get = bcm_kona_gpio_get,
322 	.direction_output = bcm_kona_gpio_direction_output,
323 	.set = bcm_kona_gpio_set,
324 	.set_config = bcm_kona_gpio_set_config,
325 	.to_irq = bcm_kona_gpio_to_irq,
326 	.base = 0,
327 };
328 
329 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
330 {
331 	struct bcm_kona_gpio *kona_gpio;
332 	void __iomem *reg_base;
333 	unsigned gpio = d->hwirq;
334 	int bank_id = GPIO_BANK(gpio);
335 	int bit = GPIO_BIT(gpio);
336 	u32 val;
337 	unsigned long flags;
338 
339 	kona_gpio = irq_data_get_irq_chip_data(d);
340 	reg_base = kona_gpio->reg_base;
341 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
342 
343 	val = readl(reg_base + GPIO_INT_STATUS(bank_id));
344 	val |= BIT(bit);
345 	writel(val, reg_base + GPIO_INT_STATUS(bank_id));
346 
347 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
348 }
349 
350 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
351 {
352 	struct bcm_kona_gpio *kona_gpio;
353 	void __iomem *reg_base;
354 	unsigned gpio = d->hwirq;
355 	int bank_id = GPIO_BANK(gpio);
356 	int bit = GPIO_BIT(gpio);
357 	u32 val;
358 	unsigned long flags;
359 
360 	kona_gpio = irq_data_get_irq_chip_data(d);
361 	reg_base = kona_gpio->reg_base;
362 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
363 
364 	val = readl(reg_base + GPIO_INT_MASK(bank_id));
365 	val |= BIT(bit);
366 	writel(val, reg_base + GPIO_INT_MASK(bank_id));
367 	gpiochip_disable_irq(&kona_gpio->gpio_chip, gpio);
368 
369 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
370 }
371 
372 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
373 {
374 	struct bcm_kona_gpio *kona_gpio;
375 	void __iomem *reg_base;
376 	unsigned gpio = d->hwirq;
377 	int bank_id = GPIO_BANK(gpio);
378 	int bit = GPIO_BIT(gpio);
379 	u32 val;
380 	unsigned long flags;
381 
382 	kona_gpio = irq_data_get_irq_chip_data(d);
383 	reg_base = kona_gpio->reg_base;
384 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
385 
386 	val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
387 	val |= BIT(bit);
388 	writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
389 	gpiochip_enable_irq(&kona_gpio->gpio_chip, gpio);
390 
391 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
392 }
393 
394 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
395 {
396 	struct bcm_kona_gpio *kona_gpio;
397 	void __iomem *reg_base;
398 	unsigned gpio = d->hwirq;
399 	u32 lvl_type;
400 	u32 val;
401 	unsigned long flags;
402 
403 	kona_gpio = irq_data_get_irq_chip_data(d);
404 	reg_base = kona_gpio->reg_base;
405 	switch (type & IRQ_TYPE_SENSE_MASK) {
406 	case IRQ_TYPE_EDGE_RISING:
407 		lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
408 		break;
409 
410 	case IRQ_TYPE_EDGE_FALLING:
411 		lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
412 		break;
413 
414 	case IRQ_TYPE_EDGE_BOTH:
415 		lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
416 		break;
417 
418 	case IRQ_TYPE_LEVEL_HIGH:
419 	case IRQ_TYPE_LEVEL_LOW:
420 		/* BCM GPIO doesn't support level triggering */
421 	default:
422 		dev_err(kona_gpio->gpio_chip.parent,
423 			"Invalid BCM GPIO irq type 0x%x\n", type);
424 		return -EINVAL;
425 	}
426 
427 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
428 
429 	val = readl(reg_base + GPIO_CONTROL(gpio));
430 	val &= ~GPIO_GPCTR0_ITR_MASK;
431 	val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
432 	writel(val, reg_base + GPIO_CONTROL(gpio));
433 
434 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
435 
436 	return 0;
437 }
438 
439 static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
440 {
441 	void __iomem *reg_base;
442 	int bit, bank_id;
443 	unsigned long sta;
444 	struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
445 	struct irq_chip *chip = irq_desc_get_chip(desc);
446 
447 	chained_irq_enter(chip, desc);
448 
449 	/*
450 	 * For bank interrupts, we can't use chip_data to store the kona_gpio
451 	 * pointer, since GIC needs it for its own purposes. Therefore, we get
452 	 * our pointer from the bank structure.
453 	 */
454 	reg_base = bank->kona_gpio->reg_base;
455 	bank_id = bank->id;
456 
457 	while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
458 		    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
459 		for_each_set_bit(bit, &sta, 32) {
460 			int hwirq = GPIO_PER_BANK * bank_id + bit;
461 			/*
462 			 * Clear interrupt before handler is called so we don't
463 			 * miss any interrupt occurred during executing them.
464 			 */
465 			writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
466 			       BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
467 			/* Invoke interrupt handler */
468 			generic_handle_domain_irq(bank->kona_gpio->irq_domain,
469 						  hwirq);
470 		}
471 	}
472 
473 	chained_irq_exit(chip, desc);
474 }
475 
476 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
477 {
478 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
479 
480 	return gpiochip_reqres_irq(&kona_gpio->gpio_chip, d->hwirq);
481 }
482 
483 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
484 {
485 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
486 
487 	gpiochip_relres_irq(&kona_gpio->gpio_chip, d->hwirq);
488 }
489 
490 static struct irq_chip bcm_gpio_irq_chip = {
491 	.name = "bcm-kona-gpio",
492 	.irq_ack = bcm_kona_gpio_irq_ack,
493 	.irq_mask = bcm_kona_gpio_irq_mask,
494 	.irq_unmask = bcm_kona_gpio_irq_unmask,
495 	.irq_set_type = bcm_kona_gpio_irq_set_type,
496 	.irq_request_resources = bcm_kona_gpio_irq_reqres,
497 	.irq_release_resources = bcm_kona_gpio_irq_relres,
498 };
499 
500 static struct of_device_id const bcm_kona_gpio_of_match[] = {
501 	{ .compatible = "brcm,kona-gpio" },
502 	{}
503 };
504 
505 /*
506  * This lock class tells lockdep that GPIO irqs are in a different
507  * category than their parents, so it won't report false recursion.
508  */
509 static struct lock_class_key gpio_lock_class;
510 static struct lock_class_key gpio_request_class;
511 
512 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
513 				 irq_hw_number_t hwirq)
514 {
515 	int ret;
516 
517 	ret = irq_set_chip_data(irq, d->host_data);
518 	if (ret < 0)
519 		return ret;
520 	irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
521 	irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
522 	irq_set_noprobe(irq);
523 
524 	return 0;
525 }
526 
527 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
528 {
529 	irq_set_chip_and_handler(irq, NULL, NULL);
530 	irq_set_chip_data(irq, NULL);
531 }
532 
533 static const struct irq_domain_ops bcm_kona_irq_ops = {
534 	.map = bcm_kona_gpio_irq_map,
535 	.unmap = bcm_kona_gpio_irq_unmap,
536 	.xlate = irq_domain_xlate_twocell,
537 };
538 
539 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
540 {
541 	void __iomem *reg_base;
542 	int i;
543 
544 	reg_base = kona_gpio->reg_base;
545 	/* disable interrupts and clear status */
546 	for (i = 0; i < kona_gpio->num_bank; i++) {
547 		/* Unlock the entire bank first */
548 		bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
549 		writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
550 		writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
551 		/* Now re-lock the bank */
552 		bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
553 	}
554 }
555 
556 static int bcm_kona_gpio_probe(struct platform_device *pdev)
557 {
558 	struct device *dev = &pdev->dev;
559 	const struct of_device_id *match;
560 	struct bcm_kona_gpio_bank *bank;
561 	struct bcm_kona_gpio *kona_gpio;
562 	struct gpio_chip *chip;
563 	int ret;
564 	int i;
565 
566 	match = of_match_device(bcm_kona_gpio_of_match, dev);
567 	if (!match) {
568 		dev_err(dev, "Failed to find gpio controller\n");
569 		return -ENODEV;
570 	}
571 
572 	kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
573 	if (!kona_gpio)
574 		return -ENOMEM;
575 
576 	kona_gpio->gpio_chip = template_chip;
577 	chip = &kona_gpio->gpio_chip;
578 	ret = platform_irq_count(pdev);
579 	if (!ret) {
580 		dev_err(dev, "Couldn't determine # GPIO banks\n");
581 		return -ENOENT;
582 	} else if (ret < 0) {
583 		return dev_err_probe(dev, ret, "Couldn't determine GPIO banks\n");
584 	}
585 	kona_gpio->num_bank = ret;
586 
587 	if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
588 		dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
589 			GPIO_MAX_BANK_NUM);
590 		return -ENXIO;
591 	}
592 	kona_gpio->banks = devm_kcalloc(dev,
593 					kona_gpio->num_bank,
594 					sizeof(*kona_gpio->banks),
595 					GFP_KERNEL);
596 	if (!kona_gpio->banks)
597 		return -ENOMEM;
598 
599 	kona_gpio->pdev = pdev;
600 	platform_set_drvdata(pdev, kona_gpio);
601 	chip->parent = dev;
602 	chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
603 
604 	kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
605 						      chip->ngpio,
606 						      &bcm_kona_irq_ops,
607 						      kona_gpio);
608 	if (!kona_gpio->irq_domain) {
609 		dev_err(dev, "Couldn't allocate IRQ domain\n");
610 		return -ENXIO;
611 	}
612 
613 	kona_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
614 	if (IS_ERR(kona_gpio->reg_base)) {
615 		ret = PTR_ERR(kona_gpio->reg_base);
616 		goto err_irq_domain;
617 	}
618 
619 	for (i = 0; i < kona_gpio->num_bank; i++) {
620 		bank = &kona_gpio->banks[i];
621 		bank->id = i;
622 		bank->irq = platform_get_irq(pdev, i);
623 		bank->kona_gpio = kona_gpio;
624 		if (bank->irq < 0) {
625 			dev_err(dev, "Couldn't get IRQ for bank %d", i);
626 			ret = -ENOENT;
627 			goto err_irq_domain;
628 		}
629 	}
630 
631 	dev_info(&pdev->dev, "Setting up Kona GPIO\n");
632 
633 	bcm_kona_gpio_reset(kona_gpio);
634 
635 	ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
636 	if (ret < 0) {
637 		dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
638 		goto err_irq_domain;
639 	}
640 	for (i = 0; i < kona_gpio->num_bank; i++) {
641 		bank = &kona_gpio->banks[i];
642 		irq_set_chained_handler_and_data(bank->irq,
643 						 bcm_kona_gpio_irq_handler,
644 						 bank);
645 	}
646 
647 	raw_spin_lock_init(&kona_gpio->lock);
648 
649 	return 0;
650 
651 err_irq_domain:
652 	irq_domain_remove(kona_gpio->irq_domain);
653 
654 	return ret;
655 }
656 
657 static struct platform_driver bcm_kona_gpio_driver = {
658 	.driver = {
659 			.name = "bcm-kona-gpio",
660 			.of_match_table = bcm_kona_gpio_of_match,
661 	},
662 	.probe = bcm_kona_gpio_probe,
663 };
664 builtin_platform_driver(bcm_kona_gpio_driver);
665