xref: /linux/drivers/gpio/gpio-bcm-kona.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
1 /*
2  * Copyright (C) 2012-2014 Broadcom Corporation
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation version 2.
7  *
8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9  * kind, whether express or implied; without even the implied warranty
10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 #include <linux/bitops.h>
15 #include <linux/err.h>
16 #include <linux/io.h>
17 #include <linux/gpio.h>
18 #include <linux/of_device.h>
19 #include <linux/of_irq.h>
20 #include <linux/module.h>
21 #include <linux/irqdomain.h>
22 #include <linux/irqchip/chained_irq.h>
23 
24 #define BCM_GPIO_PASSWD				0x00a5a501
25 #define GPIO_PER_BANK				32
26 #define GPIO_MAX_BANK_NUM			8
27 
28 #define GPIO_BANK(gpio)				((gpio) >> 5)
29 #define GPIO_BIT(gpio)				((gpio) & (GPIO_PER_BANK - 1))
30 
31 /* There is a GPIO control register for each GPIO */
32 #define GPIO_CONTROL(gpio)			(0x00000100 + ((gpio) << 2))
33 
34 /* The remaining registers are per GPIO bank */
35 #define GPIO_OUT_STATUS(bank)			(0x00000000 + ((bank) << 2))
36 #define GPIO_IN_STATUS(bank)			(0x00000020 + ((bank) << 2))
37 #define GPIO_OUT_SET(bank)			(0x00000040 + ((bank) << 2))
38 #define GPIO_OUT_CLEAR(bank)			(0x00000060 + ((bank) << 2))
39 #define GPIO_INT_STATUS(bank)			(0x00000080 + ((bank) << 2))
40 #define GPIO_INT_MASK(bank)			(0x000000a0 + ((bank) << 2))
41 #define GPIO_INT_MSKCLR(bank)			(0x000000c0 + ((bank) << 2))
42 #define GPIO_PWD_STATUS(bank)			(0x00000500 + ((bank) << 2))
43 
44 #define GPIO_GPPWR_OFFSET			0x00000520
45 
46 #define GPIO_GPCTR0_DBR_SHIFT			5
47 #define GPIO_GPCTR0_DBR_MASK			0x000001e0
48 
49 #define GPIO_GPCTR0_ITR_SHIFT			3
50 #define GPIO_GPCTR0_ITR_MASK			0x00000018
51 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE		0x00000001
52 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE	0x00000002
53 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE		0x00000003
54 
55 #define GPIO_GPCTR0_IOTR_MASK			0x00000001
56 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT		0x00000000
57 #define GPIO_GPCTR0_IOTR_CMD_INPUT		0x00000001
58 
59 #define GPIO_GPCTR0_DB_ENABLE_MASK		0x00000100
60 
61 #define LOCK_CODE				0xffffffff
62 #define UNLOCK_CODE				0x00000000
63 
64 struct bcm_kona_gpio {
65 	void __iomem *reg_base;
66 	int num_bank;
67 	spinlock_t lock;
68 	struct gpio_chip gpio_chip;
69 	struct irq_domain *irq_domain;
70 	struct bcm_kona_gpio_bank *banks;
71 	struct platform_device *pdev;
72 };
73 
74 struct bcm_kona_gpio_bank {
75 	int id;
76 	int irq;
77 	/* Used in the interrupt handler */
78 	struct bcm_kona_gpio *kona_gpio;
79 };
80 
81 static inline struct bcm_kona_gpio *to_kona_gpio(struct gpio_chip *chip)
82 {
83 	return container_of(chip, struct bcm_kona_gpio, gpio_chip);
84 }
85 
86 static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
87 						int bank_id, u32 lockcode)
88 {
89 	writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
90 	writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
91 }
92 
93 static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
94 					unsigned gpio)
95 {
96 	u32 val;
97 	unsigned long flags;
98 	int bank_id = GPIO_BANK(gpio);
99 
100 	spin_lock_irqsave(&kona_gpio->lock, flags);
101 
102 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
103 	val |= BIT(gpio);
104 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
105 
106 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
107 }
108 
109 static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
110 					unsigned gpio)
111 {
112 	u32 val;
113 	unsigned long flags;
114 	int bank_id = GPIO_BANK(gpio);
115 
116 	spin_lock_irqsave(&kona_gpio->lock, flags);
117 
118 	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
119 	val &= ~BIT(gpio);
120 	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
121 
122 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
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 = to_kona_gpio(chip);
135 	reg_base = kona_gpio->reg_base;
136 	spin_lock_irqsave(&kona_gpio->lock, flags);
137 
138 	/* determine the GPIO pin direction */
139 	val = readl(reg_base + GPIO_CONTROL(gpio));
140 	val &= GPIO_GPCTR0_IOTR_MASK;
141 
142 	/* this function only applies to output pin */
143 	if (GPIO_GPCTR0_IOTR_CMD_INPUT == val)
144 		goto out;
145 
146 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
147 
148 	val = readl(reg_base + reg_offset);
149 	val |= BIT(bit);
150 	writel(val, reg_base + reg_offset);
151 
152 out:
153 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
154 }
155 
156 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
157 {
158 	struct bcm_kona_gpio *kona_gpio;
159 	void __iomem *reg_base;
160 	int bank_id = GPIO_BANK(gpio);
161 	int bit = GPIO_BIT(gpio);
162 	u32 val, reg_offset;
163 	unsigned long flags;
164 
165 	kona_gpio = to_kona_gpio(chip);
166 	reg_base = kona_gpio->reg_base;
167 	spin_lock_irqsave(&kona_gpio->lock, flags);
168 
169 	/* determine the GPIO pin direction */
170 	val = readl(reg_base + GPIO_CONTROL(gpio));
171 	val &= GPIO_GPCTR0_IOTR_MASK;
172 
173 	/* read the GPIO bank status */
174 	reg_offset = (GPIO_GPCTR0_IOTR_CMD_INPUT == val) ?
175 	    GPIO_IN_STATUS(bank_id) : GPIO_OUT_STATUS(bank_id);
176 	val = readl(reg_base + reg_offset);
177 
178 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
179 
180 	/* return the specified bit status */
181 	return !!(val & BIT(bit));
182 }
183 
184 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
185 {
186 	struct bcm_kona_gpio *kona_gpio = to_kona_gpio(chip);
187 
188 	bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
189 	return 0;
190 }
191 
192 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
193 {
194 	struct bcm_kona_gpio *kona_gpio = to_kona_gpio(chip);
195 
196 	bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
197 }
198 
199 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
200 {
201 	struct bcm_kona_gpio *kona_gpio;
202 	void __iomem *reg_base;
203 	u32 val;
204 	unsigned long flags;
205 
206 	kona_gpio = to_kona_gpio(chip);
207 	reg_base = kona_gpio->reg_base;
208 	spin_lock_irqsave(&kona_gpio->lock, flags);
209 
210 	val = readl(reg_base + GPIO_CONTROL(gpio));
211 	val &= ~GPIO_GPCTR0_IOTR_MASK;
212 	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
213 	writel(val, reg_base + GPIO_CONTROL(gpio));
214 
215 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
216 
217 	return 0;
218 }
219 
220 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
221 					  unsigned gpio, int value)
222 {
223 	struct bcm_kona_gpio *kona_gpio;
224 	void __iomem *reg_base;
225 	int bank_id = GPIO_BANK(gpio);
226 	int bit = GPIO_BIT(gpio);
227 	u32 val, reg_offset;
228 	unsigned long flags;
229 
230 	kona_gpio = to_kona_gpio(chip);
231 	reg_base = kona_gpio->reg_base;
232 	spin_lock_irqsave(&kona_gpio->lock, flags);
233 
234 	val = readl(reg_base + GPIO_CONTROL(gpio));
235 	val &= ~GPIO_GPCTR0_IOTR_MASK;
236 	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
237 	writel(val, reg_base + GPIO_CONTROL(gpio));
238 	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
239 
240 	val = readl(reg_base + reg_offset);
241 	val |= BIT(bit);
242 	writel(val, reg_base + reg_offset);
243 
244 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
245 
246 	return 0;
247 }
248 
249 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
250 {
251 	struct bcm_kona_gpio *kona_gpio;
252 
253 	kona_gpio = to_kona_gpio(chip);
254 	if (gpio >= kona_gpio->gpio_chip.ngpio)
255 		return -ENXIO;
256 	return irq_create_mapping(kona_gpio->irq_domain, gpio);
257 }
258 
259 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
260 				      unsigned debounce)
261 {
262 	struct bcm_kona_gpio *kona_gpio;
263 	void __iomem *reg_base;
264 	u32 val, res;
265 	unsigned long flags;
266 
267 	kona_gpio = to_kona_gpio(chip);
268 	reg_base = kona_gpio->reg_base;
269 	/* debounce must be 1-128ms (or 0) */
270 	if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
271 		dev_err(chip->dev, "Debounce value %u not in range\n",
272 			debounce);
273 		return -EINVAL;
274 	}
275 
276 	/* calculate debounce bit value */
277 	if (debounce != 0) {
278 		/* Convert to ms */
279 		debounce /= 1000;
280 		/* find the MSB */
281 		res = fls(debounce) - 1;
282 		/* Check if MSB-1 is set (round up or down) */
283 		if (res > 0 && (debounce & BIT(res - 1)))
284 			res++;
285 	}
286 
287 	/* spin lock for read-modify-write of the GPIO register */
288 	spin_lock_irqsave(&kona_gpio->lock, flags);
289 
290 	val = readl(reg_base + GPIO_CONTROL(gpio));
291 	val &= ~GPIO_GPCTR0_DBR_MASK;
292 
293 	if (debounce == 0) {
294 		/* disable debounce */
295 		val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
296 	} else {
297 		val |= GPIO_GPCTR0_DB_ENABLE_MASK |
298 		    (res << GPIO_GPCTR0_DBR_SHIFT);
299 	}
300 
301 	writel(val, reg_base + GPIO_CONTROL(gpio));
302 
303 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
304 
305 	return 0;
306 }
307 
308 static struct gpio_chip template_chip = {
309 	.label = "bcm-kona-gpio",
310 	.owner = THIS_MODULE,
311 	.request = bcm_kona_gpio_request,
312 	.free = bcm_kona_gpio_free,
313 	.direction_input = bcm_kona_gpio_direction_input,
314 	.get = bcm_kona_gpio_get,
315 	.direction_output = bcm_kona_gpio_direction_output,
316 	.set = bcm_kona_gpio_set,
317 	.set_debounce = bcm_kona_gpio_set_debounce,
318 	.to_irq = bcm_kona_gpio_to_irq,
319 	.base = 0,
320 };
321 
322 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
323 {
324 	struct bcm_kona_gpio *kona_gpio;
325 	void __iomem *reg_base;
326 	unsigned gpio = d->hwirq;
327 	int bank_id = GPIO_BANK(gpio);
328 	int bit = GPIO_BIT(gpio);
329 	u32 val;
330 	unsigned long flags;
331 
332 	kona_gpio = irq_data_get_irq_chip_data(d);
333 	reg_base = kona_gpio->reg_base;
334 	spin_lock_irqsave(&kona_gpio->lock, flags);
335 
336 	val = readl(reg_base + GPIO_INT_STATUS(bank_id));
337 	val |= BIT(bit);
338 	writel(val, reg_base + GPIO_INT_STATUS(bank_id));
339 
340 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
341 }
342 
343 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
344 {
345 	struct bcm_kona_gpio *kona_gpio;
346 	void __iomem *reg_base;
347 	unsigned gpio = d->hwirq;
348 	int bank_id = GPIO_BANK(gpio);
349 	int bit = GPIO_BIT(gpio);
350 	u32 val;
351 	unsigned long flags;
352 
353 	kona_gpio = irq_data_get_irq_chip_data(d);
354 	reg_base = kona_gpio->reg_base;
355 	spin_lock_irqsave(&kona_gpio->lock, flags);
356 
357 	val = readl(reg_base + GPIO_INT_MASK(bank_id));
358 	val |= BIT(bit);
359 	writel(val, reg_base + GPIO_INT_MASK(bank_id));
360 
361 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
362 }
363 
364 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
365 {
366 	struct bcm_kona_gpio *kona_gpio;
367 	void __iomem *reg_base;
368 	unsigned gpio = d->hwirq;
369 	int bank_id = GPIO_BANK(gpio);
370 	int bit = GPIO_BIT(gpio);
371 	u32 val;
372 	unsigned long flags;
373 
374 	kona_gpio = irq_data_get_irq_chip_data(d);
375 	reg_base = kona_gpio->reg_base;
376 	spin_lock_irqsave(&kona_gpio->lock, flags);
377 
378 	val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
379 	val |= BIT(bit);
380 	writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
381 
382 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
383 }
384 
385 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
386 {
387 	struct bcm_kona_gpio *kona_gpio;
388 	void __iomem *reg_base;
389 	unsigned gpio = d->hwirq;
390 	u32 lvl_type;
391 	u32 val;
392 	unsigned long flags;
393 
394 	kona_gpio = irq_data_get_irq_chip_data(d);
395 	reg_base = kona_gpio->reg_base;
396 	switch (type & IRQ_TYPE_SENSE_MASK) {
397 	case IRQ_TYPE_EDGE_RISING:
398 		lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
399 		break;
400 
401 	case IRQ_TYPE_EDGE_FALLING:
402 		lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
403 		break;
404 
405 	case IRQ_TYPE_EDGE_BOTH:
406 		lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
407 		break;
408 
409 	case IRQ_TYPE_LEVEL_HIGH:
410 	case IRQ_TYPE_LEVEL_LOW:
411 		/* BCM GPIO doesn't support level triggering */
412 	default:
413 		dev_err(kona_gpio->gpio_chip.dev,
414 			"Invalid BCM GPIO irq type 0x%x\n", type);
415 		return -EINVAL;
416 	}
417 
418 	spin_lock_irqsave(&kona_gpio->lock, flags);
419 
420 	val = readl(reg_base + GPIO_CONTROL(gpio));
421 	val &= ~GPIO_GPCTR0_ITR_MASK;
422 	val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
423 	writel(val, reg_base + GPIO_CONTROL(gpio));
424 
425 	spin_unlock_irqrestore(&kona_gpio->lock, flags);
426 
427 	return 0;
428 }
429 
430 static void bcm_kona_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
431 {
432 	void __iomem *reg_base;
433 	int bit, bank_id;
434 	unsigned long sta;
435 	struct bcm_kona_gpio_bank *bank = irq_get_handler_data(irq);
436 	struct irq_chip *chip = irq_desc_get_chip(desc);
437 
438 	chained_irq_enter(chip, desc);
439 
440 	/*
441 	 * For bank interrupts, we can't use chip_data to store the kona_gpio
442 	 * pointer, since GIC needs it for its own purposes. Therefore, we get
443 	 * our pointer from the bank structure.
444 	 */
445 	reg_base = bank->kona_gpio->reg_base;
446 	bank_id = bank->id;
447 
448 	while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
449 		    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
450 		for_each_set_bit(bit, &sta, 32) {
451 			int hwirq = GPIO_PER_BANK * bank_id + bit;
452 			int child_irq =
453 				irq_find_mapping(bank->kona_gpio->irq_domain,
454 						 hwirq);
455 			/*
456 			 * Clear interrupt before handler is called so we don't
457 			 * miss any interrupt occurred during executing them.
458 			 */
459 			writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
460 			       BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
461 			/* Invoke interrupt handler */
462 			generic_handle_irq(child_irq);
463 		}
464 	}
465 
466 	chained_irq_exit(chip, desc);
467 }
468 
469 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
470 {
471 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
472 
473 	if (gpiochip_lock_as_irq(&kona_gpio->gpio_chip, d->hwirq)) {
474 		dev_err(kona_gpio->gpio_chip.dev,
475 			"unable to lock HW IRQ %lu for IRQ\n",
476 			d->hwirq);
477 		return -EINVAL;
478 	}
479 	return 0;
480 }
481 
482 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
483 {
484 	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
485 
486 	gpiochip_unlock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
487 }
488 
489 static struct irq_chip bcm_gpio_irq_chip = {
490 	.name = "bcm-kona-gpio",
491 	.irq_ack = bcm_kona_gpio_irq_ack,
492 	.irq_mask = bcm_kona_gpio_irq_mask,
493 	.irq_unmask = bcm_kona_gpio_irq_unmask,
494 	.irq_set_type = bcm_kona_gpio_irq_set_type,
495 	.irq_request_resources = bcm_kona_gpio_irq_reqres,
496 	.irq_release_resources = bcm_kona_gpio_irq_relres,
497 };
498 
499 static struct of_device_id const bcm_kona_gpio_of_match[] = {
500 	{ .compatible = "brcm,kona-gpio" },
501 	{}
502 };
503 
504 MODULE_DEVICE_TABLE(of, bcm_kona_gpio_of_match);
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 
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);
521 	irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
522 #ifdef CONFIG_ARM
523 	set_irq_flags(irq, IRQF_VALID);
524 #else
525 	irq_set_noprobe(irq);
526 #endif
527 
528 	return 0;
529 }
530 
531 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
532 {
533 	irq_set_chip_and_handler(irq, NULL, NULL);
534 	irq_set_chip_data(irq, NULL);
535 }
536 
537 static struct irq_domain_ops bcm_kona_irq_ops = {
538 	.map = bcm_kona_gpio_irq_map,
539 	.unmap = bcm_kona_gpio_irq_unmap,
540 	.xlate = irq_domain_xlate_twocell,
541 };
542 
543 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
544 {
545 	void __iomem *reg_base;
546 	int i;
547 
548 	reg_base = kona_gpio->reg_base;
549 	/* disable interrupts and clear status */
550 	for (i = 0; i < kona_gpio->num_bank; i++) {
551 		/* Unlock the entire bank first */
552 		bcm_kona_gpio_write_lock_regs(kona_gpio, i, UNLOCK_CODE);
553 		writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
554 		writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
555 		/* Now re-lock the bank */
556 		bcm_kona_gpio_write_lock_regs(kona_gpio, i, LOCK_CODE);
557 	}
558 }
559 
560 static int bcm_kona_gpio_probe(struct platform_device *pdev)
561 {
562 	struct device *dev = &pdev->dev;
563 	const struct of_device_id *match;
564 	struct resource *res;
565 	struct bcm_kona_gpio_bank *bank;
566 	struct bcm_kona_gpio *kona_gpio;
567 	struct gpio_chip *chip;
568 	int ret;
569 	int i;
570 
571 	match = of_match_device(bcm_kona_gpio_of_match, dev);
572 	if (!match) {
573 		dev_err(dev, "Failed to find gpio controller\n");
574 		return -ENODEV;
575 	}
576 
577 	kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
578 	if (!kona_gpio)
579 		return -ENOMEM;
580 
581 	kona_gpio->gpio_chip = template_chip;
582 	chip = &kona_gpio->gpio_chip;
583 	kona_gpio->num_bank = of_irq_count(dev->of_node);
584 	if (kona_gpio->num_bank == 0) {
585 		dev_err(dev, "Couldn't determine # GPIO banks\n");
586 		return -ENOENT;
587 	}
588 	if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
589 		dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
590 			GPIO_MAX_BANK_NUM);
591 		return -ENXIO;
592 	}
593 	kona_gpio->banks = devm_kzalloc(dev,
594 					kona_gpio->num_bank *
595 					sizeof(*kona_gpio->banks), 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->of_node = dev->of_node;
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 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
614 	kona_gpio->reg_base = devm_ioremap_resource(dev, res);
615 	if (IS_ERR(kona_gpio->reg_base)) {
616 		ret = -ENXIO;
617 		goto err_irq_domain;
618 	}
619 
620 	for (i = 0; i < kona_gpio->num_bank; i++) {
621 		bank = &kona_gpio->banks[i];
622 		bank->id = i;
623 		bank->irq = platform_get_irq(pdev, i);
624 		bank->kona_gpio = kona_gpio;
625 		if (bank->irq < 0) {
626 			dev_err(dev, "Couldn't get IRQ for bank %d", i);
627 			ret = -ENOENT;
628 			goto err_irq_domain;
629 		}
630 	}
631 
632 	dev_info(&pdev->dev, "Setting up Kona GPIO\n");
633 
634 	bcm_kona_gpio_reset(kona_gpio);
635 
636 	ret = gpiochip_add(chip);
637 	if (ret < 0) {
638 		dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
639 		goto err_irq_domain;
640 	}
641 	for (i = 0; i < chip->ngpio; i++) {
642 		int irq = bcm_kona_gpio_to_irq(chip, i);
643 		irq_set_lockdep_class(irq, &gpio_lock_class);
644 		irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip,
645 					 handle_simple_irq);
646 #ifdef CONFIG_ARM
647 		set_irq_flags(irq, IRQF_VALID);
648 #else
649 		irq_set_noprobe(irq);
650 #endif
651 	}
652 	for (i = 0; i < kona_gpio->num_bank; i++) {
653 		bank = &kona_gpio->banks[i];
654 		irq_set_chained_handler(bank->irq, bcm_kona_gpio_irq_handler);
655 		irq_set_handler_data(bank->irq, bank);
656 	}
657 
658 	spin_lock_init(&kona_gpio->lock);
659 
660 	return 0;
661 
662 err_irq_domain:
663 	irq_domain_remove(kona_gpio->irq_domain);
664 
665 	return ret;
666 }
667 
668 static struct platform_driver bcm_kona_gpio_driver = {
669 	.driver = {
670 			.name = "bcm-kona-gpio",
671 			.of_match_table = bcm_kona_gpio_of_match,
672 	},
673 	.probe = bcm_kona_gpio_probe,
674 };
675 
676 module_platform_driver(bcm_kona_gpio_driver);
677 
678 MODULE_AUTHOR("Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>");
679 MODULE_DESCRIPTION("Broadcom Kona GPIO Driver");
680 MODULE_LICENSE("GPL v2");
681