xref: /linux/drivers/gpio/gpio-bcm-kona.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
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/gpio/driver.h>
12 #include <linux/init.h>
13 #include <linux/io.h>
14 #include <linux/irqdomain.h>
15 #include <linux/irqchip/chained_irq.h>
16 #include <linux/mod_devicetable.h>
17 #include <linux/platform_device.h>
18 #include <linux/property.h>
19 
20 #define BCM_GPIO_PASSWD				0x00a5a501
21 #define GPIO_PER_BANK				32
22 #define GPIO_MAX_BANK_NUM			8
23 
24 #define GPIO_BANK(gpio)				((gpio) >> 5)
25 #define GPIO_BIT(gpio)				((gpio) & (GPIO_PER_BANK - 1))
26 
27 /* There is a GPIO control register for each GPIO */
28 #define GPIO_CONTROL(gpio)			(0x00000100 + ((gpio) << 2))
29 
30 /* The remaining registers are per GPIO bank */
31 #define GPIO_OUT_STATUS(bank)			(0x00000000 + ((bank) << 2))
32 #define GPIO_IN_STATUS(bank)			(0x00000020 + ((bank) << 2))
33 #define GPIO_OUT_SET(bank)			(0x00000040 + ((bank) << 2))
34 #define GPIO_OUT_CLEAR(bank)			(0x00000060 + ((bank) << 2))
35 #define GPIO_INT_STATUS(bank)			(0x00000080 + ((bank) << 2))
36 #define GPIO_INT_MASK(bank)			(0x000000a0 + ((bank) << 2))
37 #define GPIO_INT_MSKCLR(bank)			(0x000000c0 + ((bank) << 2))
38 #define GPIO_PWD_STATUS(bank)			(0x00000500 + ((bank) << 2))
39 
40 #define GPIO_GPPWR_OFFSET			0x00000520
41 
42 #define GPIO_GPCTR0_DBR_SHIFT			5
43 #define GPIO_GPCTR0_DBR_MASK			0x000001e0
44 
45 #define GPIO_GPCTR0_ITR_SHIFT			3
46 #define GPIO_GPCTR0_ITR_MASK			0x00000018
47 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE		0x00000001
48 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE	0x00000002
49 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE		0x00000003
50 
51 #define GPIO_GPCTR0_IOTR_MASK			0x00000001
52 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT		0x00000000
53 #define GPIO_GPCTR0_IOTR_CMD_INPUT		0x00000001
54 
55 #define GPIO_GPCTR0_DB_ENABLE_MASK		0x00000100
56 
57 #define LOCK_CODE				0xffffffff
58 #define UNLOCK_CODE				0x00000000
59 
60 struct bcm_kona_gpio {
61 	void __iomem *reg_base;
62 	int num_bank;
63 	raw_spinlock_t lock;
64 	struct gpio_chip gpio_chip;
65 	struct irq_domain *irq_domain;
66 	struct bcm_kona_gpio_bank *banks;
67 };
68 
69 struct bcm_kona_gpio_bank {
70 	int id;
71 	int irq;
72 	/* Used in the interrupt handler */
73 	struct bcm_kona_gpio *kona_gpio;
74 };
75 
76 static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
77 						int bank_id, u32 lockcode)
78 {
79 	writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
80 	writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
81 }
82 
83 static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
84 					unsigned gpio)
85 {
86 	u32 val;
87 	unsigned long flags;
88 	int bank_id = GPIO_BANK(gpio);
89 
90 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
91 
92 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
93 	val |= BIT(gpio);
94 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
95 
96 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
97 }
98 
99 static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
100 					unsigned gpio)
101 {
102 	u32 val;
103 	unsigned long flags;
104 	int bank_id = GPIO_BANK(gpio);
105 
106 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
107 
108 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
109 	val &= ~BIT(gpio);
110 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
111 
112 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
113 }
114 
115 static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
116 {
117 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
118 	void __iomem *reg_base = kona_gpio->reg_base;
119 	u32 val;
120 
121 	val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
122 	return val ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
123 }
124 
125 static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
126 {
127 	struct bcm_kona_gpio *kona_gpio;
128 	void __iomem *reg_base;
129 	int bank_id = GPIO_BANK(gpio);
130 	int bit = GPIO_BIT(gpio);
131 	u32 val, reg_offset;
132 	unsigned long flags;
133 
134 	kona_gpio = gpiochip_get_data(chip);
135 	reg_base = kona_gpio->reg_base;
136 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
137 
138 	/* this function only applies to output pin */
139 	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
140 		goto out;
141 
142 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
143 
144 	val = readl(reg_base + reg_offset);
145 	val |= BIT(bit);
146 	writel(val, reg_base + reg_offset);
147 
148 out:
149 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
150 }
151 
152 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
153 {
154 	struct bcm_kona_gpio *kona_gpio;
155 	void __iomem *reg_base;
156 	int bank_id = GPIO_BANK(gpio);
157 	int bit = GPIO_BIT(gpio);
158 	u32 val, reg_offset;
159 	unsigned long flags;
160 
161 	kona_gpio = gpiochip_get_data(chip);
162 	reg_base = kona_gpio->reg_base;
163 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
164 
165 	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
166 		reg_offset = GPIO_IN_STATUS(bank_id);
167 	else
168 		reg_offset = GPIO_OUT_STATUS(bank_id);
169 
170 	/* read the GPIO bank status */
171 	val = readl(reg_base + reg_offset);
172 
173 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
174 
175 	/* return the specified bit status */
176 	return !!(val & BIT(bit));
177 }
178 
179 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
180 {
181 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
182 
183 	bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
184 	return 0;
185 }
186 
187 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
188 {
189 	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
190 
191 	bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
192 }
193 
194 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
195 {
196 	struct bcm_kona_gpio *kona_gpio;
197 	void __iomem *reg_base;
198 	u32 val;
199 	unsigned long flags;
200 
201 	kona_gpio = gpiochip_get_data(chip);
202 	reg_base = kona_gpio->reg_base;
203 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
204 
205 	val = readl(reg_base + GPIO_CONTROL(gpio));
206 	val &= ~GPIO_GPCTR0_IOTR_MASK;
207 	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
208 	writel(val, reg_base + GPIO_CONTROL(gpio));
209 
210 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
211 
212 	return 0;
213 }
214 
215 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
216 					  unsigned gpio, int value)
217 {
218 	struct bcm_kona_gpio *kona_gpio;
219 	void __iomem *reg_base;
220 	int bank_id = GPIO_BANK(gpio);
221 	int bit = GPIO_BIT(gpio);
222 	u32 val, reg_offset;
223 	unsigned long flags;
224 
225 	kona_gpio = gpiochip_get_data(chip);
226 	reg_base = kona_gpio->reg_base;
227 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
228 
229 	val = readl(reg_base + GPIO_CONTROL(gpio));
230 	val &= ~GPIO_GPCTR0_IOTR_MASK;
231 	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
232 	writel(val, reg_base + GPIO_CONTROL(gpio));
233 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
234 
235 	val = readl(reg_base + reg_offset);
236 	val |= BIT(bit);
237 	writel(val, reg_base + reg_offset);
238 
239 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
240 
241 	return 0;
242 }
243 
244 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
245 {
246 	struct bcm_kona_gpio *kona_gpio;
247 
248 	kona_gpio = gpiochip_get_data(chip);
249 	if (gpio >= kona_gpio->gpio_chip.ngpio)
250 		return -ENXIO;
251 	return irq_create_mapping(kona_gpio->irq_domain, gpio);
252 }
253 
254 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
255 				      unsigned debounce)
256 {
257 	struct bcm_kona_gpio *kona_gpio;
258 	void __iomem *reg_base;
259 	u32 val, res;
260 	unsigned long flags;
261 
262 	kona_gpio = gpiochip_get_data(chip);
263 	reg_base = kona_gpio->reg_base;
264 	/* debounce must be 1-128ms (or 0) */
265 	if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
266 		dev_err(chip->parent, "Debounce value %u not in range\n",
267 			debounce);
268 		return -EINVAL;
269 	}
270 
271 	/* calculate debounce bit value */
272 	if (debounce != 0) {
273 		/* Convert to ms */
274 		debounce /= 1000;
275 		/* find the MSB */
276 		res = fls(debounce) - 1;
277 		/* Check if MSB-1 is set (round up or down) */
278 		if (res > 0 && (debounce & BIT(res - 1)))
279 			res++;
280 	}
281 
282 	/* spin lock for read-modify-write of the GPIO register */
283 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
284 
285 	val = readl(reg_base + GPIO_CONTROL(gpio));
286 	val &= ~GPIO_GPCTR0_DBR_MASK;
287 
288 	if (debounce == 0) {
289 		/* disable debounce */
290 		val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
291 	} else {
292 		val |= GPIO_GPCTR0_DB_ENABLE_MASK |
293 		    (res << GPIO_GPCTR0_DBR_SHIFT);
294 	}
295 
296 	writel(val, reg_base + GPIO_CONTROL(gpio));
297 
298 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
299 
300 	return 0;
301 }
302 
303 static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
304 				    unsigned long config)
305 {
306 	u32 debounce;
307 
308 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
309 		return -ENOTSUPP;
310 
311 	debounce = pinconf_to_config_argument(config);
312 	return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
313 }
314 
315 static const struct gpio_chip template_chip = {
316 	.label = "bcm-kona-gpio",
317 	.owner = THIS_MODULE,
318 	.request = bcm_kona_gpio_request,
319 	.free = bcm_kona_gpio_free,
320 	.get_direction = bcm_kona_gpio_get_dir,
321 	.direction_input = bcm_kona_gpio_direction_input,
322 	.get = bcm_kona_gpio_get,
323 	.direction_output = bcm_kona_gpio_direction_output,
324 	.set = bcm_kona_gpio_set,
325 	.set_config = bcm_kona_gpio_set_config,
326 	.to_irq = bcm_kona_gpio_to_irq,
327 	.base = 0,
328 };
329 
330 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
331 {
332 	struct bcm_kona_gpio *kona_gpio;
333 	void __iomem *reg_base;
334 	unsigned gpio = d->hwirq;
335 	int bank_id = GPIO_BANK(gpio);
336 	int bit = GPIO_BIT(gpio);
337 	u32 val;
338 	unsigned long flags;
339 
340 	kona_gpio = irq_data_get_irq_chip_data(d);
341 	reg_base = kona_gpio->reg_base;
342 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
343 
344 	val = readl(reg_base + GPIO_INT_STATUS(bank_id));
345 	val |= BIT(bit);
346 	writel(val, reg_base + GPIO_INT_STATUS(bank_id));
347 
348 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
349 }
350 
351 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
352 {
353 	struct bcm_kona_gpio *kona_gpio;
354 	void __iomem *reg_base;
355 	unsigned gpio = d->hwirq;
356 	int bank_id = GPIO_BANK(gpio);
357 	int bit = GPIO_BIT(gpio);
358 	u32 val;
359 	unsigned long flags;
360 
361 	kona_gpio = irq_data_get_irq_chip_data(d);
362 	reg_base = kona_gpio->reg_base;
363 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
364 
365 	val = readl(reg_base + GPIO_INT_MASK(bank_id));
366 	val |= BIT(bit);
367 	writel(val, reg_base + GPIO_INT_MASK(bank_id));
368 	gpiochip_disable_irq(&kona_gpio->gpio_chip, gpio);
369 
370 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
371 }
372 
373 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
374 {
375 	struct bcm_kona_gpio *kona_gpio;
376 	void __iomem *reg_base;
377 	unsigned gpio = d->hwirq;
378 	int bank_id = GPIO_BANK(gpio);
379 	int bit = GPIO_BIT(gpio);
380 	u32 val;
381 	unsigned long flags;
382 
383 	kona_gpio = irq_data_get_irq_chip_data(d);
384 	reg_base = kona_gpio->reg_base;
385 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
386 
387 	val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
388 	val |= BIT(bit);
389 	writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
390 	gpiochip_enable_irq(&kona_gpio->gpio_chip, gpio);
391 
392 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
393 }
394 
395 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
396 {
397 	struct bcm_kona_gpio *kona_gpio;
398 	void __iomem *reg_base;
399 	unsigned gpio = d->hwirq;
400 	u32 lvl_type;
401 	u32 val;
402 	unsigned long flags;
403 
404 	kona_gpio = irq_data_get_irq_chip_data(d);
405 	reg_base = kona_gpio->reg_base;
406 	switch (type & IRQ_TYPE_SENSE_MASK) {
407 	case IRQ_TYPE_EDGE_RISING:
408 		lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
409 		break;
410 
411 	case IRQ_TYPE_EDGE_FALLING:
412 		lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
413 		break;
414 
415 	case IRQ_TYPE_EDGE_BOTH:
416 		lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
417 		break;
418 
419 	case IRQ_TYPE_LEVEL_HIGH:
420 	case IRQ_TYPE_LEVEL_LOW:
421 		/* BCM GPIO doesn't support level triggering */
422 	default:
423 		dev_err(kona_gpio->gpio_chip.parent,
424 			"Invalid BCM GPIO irq type 0x%x\n", type);
425 		return -EINVAL;
426 	}
427 
428 	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
429 
430 	val = readl(reg_base + GPIO_CONTROL(gpio));
431 	val &= ~GPIO_GPCTR0_ITR_MASK;
432 	val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
433 	writel(val, reg_base + GPIO_CONTROL(gpio));
434 
435 	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
436 
437 	return 0;
438 }
439 
440 static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
441 {
442 	void __iomem *reg_base;
443 	int bit, bank_id;
444 	unsigned long sta;
445 	struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
446 	struct irq_chip *chip = irq_desc_get_chip(desc);
447 
448 	chained_irq_enter(chip, desc);
449 
450 	/*
451 	 * For bank interrupts, we can't use chip_data to store the kona_gpio
452 	 * pointer, since GIC needs it for its own purposes. Therefore, we get
453 	 * our pointer from the bank structure.
454 	 */
455 	reg_base = bank->kona_gpio->reg_base;
456 	bank_id = bank->id;
457 
458 	while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
459 		    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
460 		for_each_set_bit(bit, &sta, 32) {
461 			int hwirq = GPIO_PER_BANK * bank_id + bit;
462 			/*
463 			 * Clear interrupt before handler is called so we don't
464 			 * miss any interrupt occurred during executing them.
465 			 */
466 			writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
467 			       BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
468 			/* Invoke interrupt handler */
469 			generic_handle_domain_irq(bank->kona_gpio->irq_domain,
470 						  hwirq);
471 		}
472 	}
473 
474 	chained_irq_exit(chip, desc);
475 }
476 
477 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
478 {
479 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
480 
481 	return gpiochip_reqres_irq(&kona_gpio->gpio_chip, d->hwirq);
482 }
483 
484 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
485 {
486 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
487 
488 	gpiochip_relres_irq(&kona_gpio->gpio_chip, d->hwirq);
489 }
490 
491 static struct irq_chip bcm_gpio_irq_chip = {
492 	.name = "bcm-kona-gpio",
493 	.irq_ack = bcm_kona_gpio_irq_ack,
494 	.irq_mask = bcm_kona_gpio_irq_mask,
495 	.irq_unmask = bcm_kona_gpio_irq_unmask,
496 	.irq_set_type = bcm_kona_gpio_irq_set_type,
497 	.irq_request_resources = bcm_kona_gpio_irq_reqres,
498 	.irq_release_resources = bcm_kona_gpio_irq_relres,
499 };
500 
501 static struct of_device_id const bcm_kona_gpio_of_match[] = {
502 	{ .compatible = "brcm,kona-gpio" },
503 	{}
504 };
505 
506 /*
507  * This lock class tells lockdep that GPIO irqs are in a different
508  * category than their parents, so it won't report false recursion.
509  */
510 static struct lock_class_key gpio_lock_class;
511 static struct lock_class_key gpio_request_class;
512 
513 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
514 				 irq_hw_number_t hwirq)
515 {
516 	int ret;
517 
518 	ret = irq_set_chip_data(irq, d->host_data);
519 	if (ret < 0)
520 		return ret;
521 	irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
522 	irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
523 	irq_set_noprobe(irq);
524 
525 	return 0;
526 }
527 
528 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
529 {
530 	irq_set_chip_and_handler(irq, NULL, NULL);
531 	irq_set_chip_data(irq, NULL);
532 }
533 
534 static const struct irq_domain_ops bcm_kona_irq_ops = {
535 	.map = bcm_kona_gpio_irq_map,
536 	.unmap = bcm_kona_gpio_irq_unmap,
537 	.xlate = irq_domain_xlate_twocell,
538 };
539 
540 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
541 {
542 	void __iomem *reg_base;
543 	int i;
544 
545 	reg_base = kona_gpio->reg_base;
546 	/* disable interrupts and clear status */
547 	for (i = 0; i < kona_gpio->num_bank; i++) {
548 		/* Unlock the entire bank first */
549 		bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
550 		writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
551 		writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
552 		/* Now re-lock the bank */
553 		bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
554 	}
555 }
556 
557 static int bcm_kona_gpio_probe(struct platform_device *pdev)
558 {
559 	struct device *dev = &pdev->dev;
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 	kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
567 	if (!kona_gpio)
568 		return -ENOMEM;
569 
570 	kona_gpio->gpio_chip = template_chip;
571 	chip = &kona_gpio->gpio_chip;
572 	ret = platform_irq_count(pdev);
573 	if (!ret) {
574 		dev_err(dev, "Couldn't determine # GPIO banks\n");
575 		return -ENOENT;
576 	} else if (ret < 0) {
577 		return dev_err_probe(dev, ret, "Couldn't determine GPIO banks\n");
578 	}
579 	kona_gpio->num_bank = ret;
580 
581 	if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
582 		dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
583 			GPIO_MAX_BANK_NUM);
584 		return -ENXIO;
585 	}
586 	kona_gpio->banks = devm_kcalloc(dev,
587 					kona_gpio->num_bank,
588 					sizeof(*kona_gpio->banks),
589 					GFP_KERNEL);
590 	if (!kona_gpio->banks)
591 		return -ENOMEM;
592 
593 	chip->parent = dev;
594 	chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
595 
596 	kona_gpio->irq_domain = irq_domain_create_linear(dev_fwnode(dev),
597 							 chip->ngpio,
598 							 &bcm_kona_irq_ops,
599 							 kona_gpio);
600 	if (!kona_gpio->irq_domain) {
601 		dev_err(dev, "Couldn't allocate IRQ domain\n");
602 		return -ENXIO;
603 	}
604 
605 	kona_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
606 	if (IS_ERR(kona_gpio->reg_base)) {
607 		ret = PTR_ERR(kona_gpio->reg_base);
608 		goto err_irq_domain;
609 	}
610 
611 	for (i = 0; i < kona_gpio->num_bank; i++) {
612 		bank = &kona_gpio->banks[i];
613 		bank->id = i;
614 		bank->irq = platform_get_irq(pdev, i);
615 		bank->kona_gpio = kona_gpio;
616 		if (bank->irq < 0) {
617 			dev_err(dev, "Couldn't get IRQ for bank %d", i);
618 			ret = -ENOENT;
619 			goto err_irq_domain;
620 		}
621 	}
622 
623 	dev_info(&pdev->dev, "Setting up Kona GPIO\n");
624 
625 	bcm_kona_gpio_reset(kona_gpio);
626 
627 	ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
628 	if (ret < 0) {
629 		dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
630 		goto err_irq_domain;
631 	}
632 	for (i = 0; i < kona_gpio->num_bank; i++) {
633 		bank = &kona_gpio->banks[i];
634 		irq_set_chained_handler_and_data(bank->irq,
635 						 bcm_kona_gpio_irq_handler,
636 						 bank);
637 	}
638 
639 	raw_spin_lock_init(&kona_gpio->lock);
640 
641 	return 0;
642 
643 err_irq_domain:
644 	irq_domain_remove(kona_gpio->irq_domain);
645 
646 	return ret;
647 }
648 
649 static struct platform_driver bcm_kona_gpio_driver = {
650 	.driver = {
651 			.name = "bcm-kona-gpio",
652 			.of_match_table = bcm_kona_gpio_of_match,
653 	},
654 	.probe = bcm_kona_gpio_probe,
655 };
656 builtin_platform_driver(bcm_kona_gpio_driver);
657