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v5.9
 
  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/init.h>
 23#include <linux/irqdomain.h>
 24#include <linux/irqchip/chained_irq.h>
 25
 26#define BCM_GPIO_PASSWD				0x00a5a501
 27#define GPIO_PER_BANK				32
 28#define GPIO_MAX_BANK_NUM			8
 29
 30#define GPIO_BANK(gpio)				((gpio) >> 5)
 31#define GPIO_BIT(gpio)				((gpio) & (GPIO_PER_BANK - 1))
 32
 33/* There is a GPIO control register for each GPIO */
 34#define GPIO_CONTROL(gpio)			(0x00000100 + ((gpio) << 2))
 35
 36/* The remaining registers are per GPIO bank */
 37#define GPIO_OUT_STATUS(bank)			(0x00000000 + ((bank) << 2))
 38#define GPIO_IN_STATUS(bank)			(0x00000020 + ((bank) << 2))
 39#define GPIO_OUT_SET(bank)			(0x00000040 + ((bank) << 2))
 40#define GPIO_OUT_CLEAR(bank)			(0x00000060 + ((bank) << 2))
 41#define GPIO_INT_STATUS(bank)			(0x00000080 + ((bank) << 2))
 42#define GPIO_INT_MASK(bank)			(0x000000a0 + ((bank) << 2))
 43#define GPIO_INT_MSKCLR(bank)			(0x000000c0 + ((bank) << 2))
 44#define GPIO_PWD_STATUS(bank)			(0x00000500 + ((bank) << 2))
 45
 46#define GPIO_GPPWR_OFFSET			0x00000520
 47
 48#define GPIO_GPCTR0_DBR_SHIFT			5
 49#define GPIO_GPCTR0_DBR_MASK			0x000001e0
 50
 51#define GPIO_GPCTR0_ITR_SHIFT			3
 52#define GPIO_GPCTR0_ITR_MASK			0x00000018
 53#define GPIO_GPCTR0_ITR_CMD_RISING_EDGE		0x00000001
 54#define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE	0x00000002
 55#define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE		0x00000003
 56
 57#define GPIO_GPCTR0_IOTR_MASK			0x00000001
 58#define GPIO_GPCTR0_IOTR_CMD_0UTPUT		0x00000000
 59#define GPIO_GPCTR0_IOTR_CMD_INPUT		0x00000001
 60
 61#define GPIO_GPCTR0_DB_ENABLE_MASK		0x00000100
 62
 63#define LOCK_CODE				0xffffffff
 64#define UNLOCK_CODE				0x00000000
 65
 66struct bcm_kona_gpio {
 67	void __iomem *reg_base;
 68	int num_bank;
 69	raw_spinlock_t lock;
 70	struct gpio_chip gpio_chip;
 71	struct irq_domain *irq_domain;
 72	struct bcm_kona_gpio_bank *banks;
 73	struct platform_device *pdev;
 74};
 75
 76struct bcm_kona_gpio_bank {
 77	int id;
 78	int irq;
 79	/* Used in the interrupt handler */
 80	struct bcm_kona_gpio *kona_gpio;
 81};
 82
 83static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
 84						int bank_id, u32 lockcode)
 85{
 86	writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
 87	writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
 88}
 89
 90static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
 91					unsigned gpio)
 92{
 93	u32 val;
 94	unsigned long flags;
 95	int bank_id = GPIO_BANK(gpio);
 96
 97	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 98
 99	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
100	val |= BIT(gpio);
101	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
102
103	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
104}
105
106static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
107					unsigned gpio)
108{
109	u32 val;
110	unsigned long flags;
111	int bank_id = GPIO_BANK(gpio);
112
113	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
114
115	val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
116	val &= ~BIT(gpio);
117	bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
118
119	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
120}
121
122static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
123{
124	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
125	void __iomem *reg_base = kona_gpio->reg_base;
126	u32 val;
127
128	val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
129	return val ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
130}
131
132static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
133{
134	struct bcm_kona_gpio *kona_gpio;
135	void __iomem *reg_base;
136	int bank_id = GPIO_BANK(gpio);
137	int bit = GPIO_BIT(gpio);
138	u32 val, reg_offset;
139	unsigned long flags;
140
141	kona_gpio = gpiochip_get_data(chip);
142	reg_base = kona_gpio->reg_base;
143	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
144
145	/* this function only applies to output pin */
146	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
147		goto out;
148
149	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
150
151	val = readl(reg_base + reg_offset);
152	val |= BIT(bit);
153	writel(val, reg_base + reg_offset);
154
155out:
156	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
157}
158
159static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
160{
161	struct bcm_kona_gpio *kona_gpio;
162	void __iomem *reg_base;
163	int bank_id = GPIO_BANK(gpio);
164	int bit = GPIO_BIT(gpio);
165	u32 val, reg_offset;
166	unsigned long flags;
167
168	kona_gpio = gpiochip_get_data(chip);
169	reg_base = kona_gpio->reg_base;
170	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
171
172	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
173		reg_offset = GPIO_IN_STATUS(bank_id);
174	else
175		reg_offset = GPIO_OUT_STATUS(bank_id);
176
177	/* read the GPIO bank status */
178	val = readl(reg_base + reg_offset);
179
180	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
181
182	/* return the specified bit status */
183	return !!(val & BIT(bit));
184}
185
186static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
187{
188	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
189
190	bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
191	return 0;
192}
193
194static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
195{
196	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
197
198	bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
199}
200
201static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
202{
203	struct bcm_kona_gpio *kona_gpio;
204	void __iomem *reg_base;
205	u32 val;
206	unsigned long flags;
207
208	kona_gpio = gpiochip_get_data(chip);
209	reg_base = kona_gpio->reg_base;
210	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
211
212	val = readl(reg_base + GPIO_CONTROL(gpio));
213	val &= ~GPIO_GPCTR0_IOTR_MASK;
214	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
215	writel(val, reg_base + GPIO_CONTROL(gpio));
216
217	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
218
219	return 0;
220}
221
222static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
223					  unsigned gpio, int value)
224{
225	struct bcm_kona_gpio *kona_gpio;
226	void __iomem *reg_base;
227	int bank_id = GPIO_BANK(gpio);
228	int bit = GPIO_BIT(gpio);
229	u32 val, reg_offset;
230	unsigned long flags;
231
232	kona_gpio = gpiochip_get_data(chip);
233	reg_base = kona_gpio->reg_base;
234	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
235
236	val = readl(reg_base + GPIO_CONTROL(gpio));
237	val &= ~GPIO_GPCTR0_IOTR_MASK;
238	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
239	writel(val, reg_base + GPIO_CONTROL(gpio));
240	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
241
242	val = readl(reg_base + reg_offset);
243	val |= BIT(bit);
244	writel(val, reg_base + reg_offset);
245
246	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
247
248	return 0;
249}
250
251static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
252{
253	struct bcm_kona_gpio *kona_gpio;
254
255	kona_gpio = gpiochip_get_data(chip);
256	if (gpio >= kona_gpio->gpio_chip.ngpio)
257		return -ENXIO;
258	return irq_create_mapping(kona_gpio->irq_domain, gpio);
259}
260
261static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
262				      unsigned debounce)
263{
264	struct bcm_kona_gpio *kona_gpio;
265	void __iomem *reg_base;
266	u32 val, res;
267	unsigned long flags;
268
269	kona_gpio = gpiochip_get_data(chip);
270	reg_base = kona_gpio->reg_base;
271	/* debounce must be 1-128ms (or 0) */
272	if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
273		dev_err(chip->parent, "Debounce value %u not in range\n",
274			debounce);
275		return -EINVAL;
276	}
277
278	/* calculate debounce bit value */
279	if (debounce != 0) {
280		/* Convert to ms */
281		debounce /= 1000;
282		/* find the MSB */
283		res = fls(debounce) - 1;
284		/* Check if MSB-1 is set (round up or down) */
285		if (res > 0 && (debounce & BIT(res - 1)))
286			res++;
287	}
288
289	/* spin lock for read-modify-write of the GPIO register */
290	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
291
292	val = readl(reg_base + GPIO_CONTROL(gpio));
293	val &= ~GPIO_GPCTR0_DBR_MASK;
294
295	if (debounce == 0) {
296		/* disable debounce */
297		val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
298	} else {
299		val |= GPIO_GPCTR0_DB_ENABLE_MASK |
300		    (res << GPIO_GPCTR0_DBR_SHIFT);
301	}
302
303	writel(val, reg_base + GPIO_CONTROL(gpio));
304
305	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
306
307	return 0;
308}
309
310static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
311				    unsigned long config)
312{
313	u32 debounce;
314
315	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
316		return -ENOTSUPP;
317
318	debounce = pinconf_to_config_argument(config);
319	return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
320}
321
322static const struct gpio_chip template_chip = {
323	.label = "bcm-kona-gpio",
324	.owner = THIS_MODULE,
325	.request = bcm_kona_gpio_request,
326	.free = bcm_kona_gpio_free,
327	.get_direction = bcm_kona_gpio_get_dir,
328	.direction_input = bcm_kona_gpio_direction_input,
329	.get = bcm_kona_gpio_get,
330	.direction_output = bcm_kona_gpio_direction_output,
331	.set = bcm_kona_gpio_set,
332	.set_config = bcm_kona_gpio_set_config,
333	.to_irq = bcm_kona_gpio_to_irq,
334	.base = 0,
335};
336
337static void bcm_kona_gpio_irq_ack(struct irq_data *d)
338{
339	struct bcm_kona_gpio *kona_gpio;
340	void __iomem *reg_base;
341	unsigned gpio = d->hwirq;
342	int bank_id = GPIO_BANK(gpio);
343	int bit = GPIO_BIT(gpio);
344	u32 val;
345	unsigned long flags;
346
347	kona_gpio = irq_data_get_irq_chip_data(d);
348	reg_base = kona_gpio->reg_base;
349	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
350
351	val = readl(reg_base + GPIO_INT_STATUS(bank_id));
352	val |= BIT(bit);
353	writel(val, reg_base + GPIO_INT_STATUS(bank_id));
354
355	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
356}
357
358static void bcm_kona_gpio_irq_mask(struct irq_data *d)
359{
360	struct bcm_kona_gpio *kona_gpio;
361	void __iomem *reg_base;
362	unsigned gpio = d->hwirq;
363	int bank_id = GPIO_BANK(gpio);
364	int bit = GPIO_BIT(gpio);
365	u32 val;
366	unsigned long flags;
367
368	kona_gpio = irq_data_get_irq_chip_data(d);
369	reg_base = kona_gpio->reg_base;
370	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
371
372	val = readl(reg_base + GPIO_INT_MASK(bank_id));
373	val |= BIT(bit);
374	writel(val, reg_base + GPIO_INT_MASK(bank_id));
375	gpiochip_disable_irq(&kona_gpio->gpio_chip, gpio);
376
377	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
378}
379
380static 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	gpiochip_enable_irq(&kona_gpio->gpio_chip, gpio);
398
399	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
400}
401
402static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
403{
404	struct bcm_kona_gpio *kona_gpio;
405	void __iomem *reg_base;
406	unsigned gpio = d->hwirq;
407	u32 lvl_type;
408	u32 val;
409	unsigned long flags;
410
411	kona_gpio = irq_data_get_irq_chip_data(d);
412	reg_base = kona_gpio->reg_base;
413	switch (type & IRQ_TYPE_SENSE_MASK) {
414	case IRQ_TYPE_EDGE_RISING:
415		lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
416		break;
417
418	case IRQ_TYPE_EDGE_FALLING:
419		lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
420		break;
421
422	case IRQ_TYPE_EDGE_BOTH:
423		lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
424		break;
425
426	case IRQ_TYPE_LEVEL_HIGH:
427	case IRQ_TYPE_LEVEL_LOW:
428		/* BCM GPIO doesn't support level triggering */
429	default:
430		dev_err(kona_gpio->gpio_chip.parent,
431			"Invalid BCM GPIO irq type 0x%x\n", type);
432		return -EINVAL;
433	}
434
435	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
436
437	val = readl(reg_base + GPIO_CONTROL(gpio));
438	val &= ~GPIO_GPCTR0_ITR_MASK;
439	val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
440	writel(val, reg_base + GPIO_CONTROL(gpio));
441
442	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
443
444	return 0;
445}
446
447static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
448{
449	void __iomem *reg_base;
450	int bit, bank_id;
451	unsigned long sta;
452	struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
453	struct irq_chip *chip = irq_desc_get_chip(desc);
454
455	chained_irq_enter(chip, desc);
456
457	/*
458	 * For bank interrupts, we can't use chip_data to store the kona_gpio
459	 * pointer, since GIC needs it for its own purposes. Therefore, we get
460	 * our pointer from the bank structure.
461	 */
462	reg_base = bank->kona_gpio->reg_base;
463	bank_id = bank->id;
464
465	while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
466		    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
467		for_each_set_bit(bit, &sta, 32) {
468			int hwirq = GPIO_PER_BANK * bank_id + bit;
469			int child_irq =
470				irq_find_mapping(bank->kona_gpio->irq_domain,
471						 hwirq);
472			/*
473			 * Clear interrupt before handler is called so we don't
474			 * miss any interrupt occurred during executing them.
475			 */
476			writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
477			       BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
478			/* Invoke interrupt handler */
479			generic_handle_irq(child_irq);
 
480		}
481	}
482
483	chained_irq_exit(chip, desc);
484}
485
486static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
487{
488	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
489
490	return gpiochip_reqres_irq(&kona_gpio->gpio_chip, d->hwirq);
491}
492
493static void bcm_kona_gpio_irq_relres(struct irq_data *d)
494{
495	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
496
497	gpiochip_relres_irq(&kona_gpio->gpio_chip, d->hwirq);
498}
499
500static struct irq_chip bcm_gpio_irq_chip = {
501	.name = "bcm-kona-gpio",
502	.irq_ack = bcm_kona_gpio_irq_ack,
503	.irq_mask = bcm_kona_gpio_irq_mask,
504	.irq_unmask = bcm_kona_gpio_irq_unmask,
505	.irq_set_type = bcm_kona_gpio_irq_set_type,
506	.irq_request_resources = bcm_kona_gpio_irq_reqres,
507	.irq_release_resources = bcm_kona_gpio_irq_relres,
508};
509
510static struct of_device_id const bcm_kona_gpio_of_match[] = {
511	{ .compatible = "brcm,kona-gpio" },
512	{}
513};
514
515/*
516 * This lock class tells lockdep that GPIO irqs are in a different
517 * category than their parents, so it won't report false recursion.
518 */
519static struct lock_class_key gpio_lock_class;
520static struct lock_class_key gpio_request_class;
521
522static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
523				 irq_hw_number_t hwirq)
524{
525	int ret;
526
527	ret = irq_set_chip_data(irq, d->host_data);
528	if (ret < 0)
529		return ret;
530	irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
531	irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
532	irq_set_noprobe(irq);
533
534	return 0;
535}
536
537static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
538{
539	irq_set_chip_and_handler(irq, NULL, NULL);
540	irq_set_chip_data(irq, NULL);
541}
542
543static const struct irq_domain_ops bcm_kona_irq_ops = {
544	.map = bcm_kona_gpio_irq_map,
545	.unmap = bcm_kona_gpio_irq_unmap,
546	.xlate = irq_domain_xlate_twocell,
547};
548
549static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
550{
551	void __iomem *reg_base;
552	int i;
553
554	reg_base = kona_gpio->reg_base;
555	/* disable interrupts and clear status */
556	for (i = 0; i < kona_gpio->num_bank; i++) {
557		/* Unlock the entire bank first */
558		bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
559		writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
560		writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
561		/* Now re-lock the bank */
562		bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
563	}
564}
565
566static int bcm_kona_gpio_probe(struct platform_device *pdev)
567{
568	struct device *dev = &pdev->dev;
569	const struct of_device_id *match;
570	struct bcm_kona_gpio_bank *bank;
571	struct bcm_kona_gpio *kona_gpio;
572	struct gpio_chip *chip;
573	int ret;
574	int i;
575
576	match = of_match_device(bcm_kona_gpio_of_match, dev);
577	if (!match) {
578		dev_err(dev, "Failed to find gpio controller\n");
579		return -ENODEV;
580	}
581
582	kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
583	if (!kona_gpio)
584		return -ENOMEM;
585
586	kona_gpio->gpio_chip = template_chip;
587	chip = &kona_gpio->gpio_chip;
588	ret = platform_irq_count(pdev);
589	if (!ret) {
590		dev_err(dev, "Couldn't determine # GPIO banks\n");
591		return -ENOENT;
592	} else if (ret < 0) {
593		if (ret != -EPROBE_DEFER)
594			dev_err(dev, "Couldn't determine GPIO banks: (%pe)\n",
595				ERR_PTR(ret));
596		return ret;
597	}
598	kona_gpio->num_bank = ret;
599
600	if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
601		dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
602			GPIO_MAX_BANK_NUM);
603		return -ENXIO;
604	}
605	kona_gpio->banks = devm_kcalloc(dev,
606					kona_gpio->num_bank,
607					sizeof(*kona_gpio->banks),
608					GFP_KERNEL);
609	if (!kona_gpio->banks)
610		return -ENOMEM;
611
612	kona_gpio->pdev = pdev;
613	platform_set_drvdata(pdev, kona_gpio);
614	chip->of_node = dev->of_node;
615	chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
616
617	kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
618						      chip->ngpio,
619						      &bcm_kona_irq_ops,
620						      kona_gpio);
621	if (!kona_gpio->irq_domain) {
622		dev_err(dev, "Couldn't allocate IRQ domain\n");
623		return -ENXIO;
624	}
625
626	kona_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
627	if (IS_ERR(kona_gpio->reg_base)) {
628		ret = PTR_ERR(kona_gpio->reg_base);
629		goto err_irq_domain;
630	}
631
632	for (i = 0; i < kona_gpio->num_bank; i++) {
633		bank = &kona_gpio->banks[i];
634		bank->id = i;
635		bank->irq = platform_get_irq(pdev, i);
636		bank->kona_gpio = kona_gpio;
637		if (bank->irq < 0) {
638			dev_err(dev, "Couldn't get IRQ for bank %d", i);
639			ret = -ENOENT;
640			goto err_irq_domain;
641		}
642	}
643
644	dev_info(&pdev->dev, "Setting up Kona GPIO\n");
645
646	bcm_kona_gpio_reset(kona_gpio);
647
648	ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
649	if (ret < 0) {
650		dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
651		goto err_irq_domain;
652	}
653	for (i = 0; i < kona_gpio->num_bank; i++) {
654		bank = &kona_gpio->banks[i];
655		irq_set_chained_handler_and_data(bank->irq,
656						 bcm_kona_gpio_irq_handler,
657						 bank);
658	}
659
660	raw_spin_lock_init(&kona_gpio->lock);
661
662	return 0;
663
664err_irq_domain:
665	irq_domain_remove(kona_gpio->irq_domain);
666
667	return ret;
668}
669
670static struct platform_driver bcm_kona_gpio_driver = {
671	.driver = {
672			.name = "bcm-kona-gpio",
673			.of_match_table = bcm_kona_gpio_of_match,
674	},
675	.probe = bcm_kona_gpio_probe,
676};
677builtin_platform_driver(bcm_kona_gpio_driver);
v6.2
  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
 58struct 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
 68struct 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
 75static 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
 82static 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
 98static 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
114static 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
124static 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
147out:
148	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
149}
150
151static 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
178static 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
186static 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
193static 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
214static 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
243static 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
253static 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
302static 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
314static 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
329static 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
350static 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
372static 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
394static 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
439static 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
476static 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
483static 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
490static 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
500static 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 */
509static struct lock_class_key gpio_lock_class;
510static struct lock_class_key gpio_request_class;
511
512static 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
527static 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
533static 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
539static 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
556static 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
651err_irq_domain:
652	irq_domain_remove(kona_gpio->irq_domain);
653
654	return ret;
655}
656
657static 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};
664builtin_platform_driver(bcm_kona_gpio_driver);