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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);
v6.13.7
  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
 60struct 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
 69struct bcm_kona_gpio_bank {
 70	int id;
 71	int irq;
 72	/*
 73	 * Used to keep track of lock/unlock operations for each GPIO in the
 74	 * bank.
 75	 *
 76	 * All GPIOs are locked by default (see bcm_kona_gpio_reset), and the
 77	 * unlock count for all GPIOs is 0 by default. Each unlock increments
 78	 * the counter, and each lock decrements the counter.
 79	 *
 80	 * The lock function only locks the GPIO once its unlock counter is
 81	 * down to 0. This is necessary because the GPIO is unlocked in two
 82	 * places in this driver: once for requested GPIOs, and once for
 83	 * requested IRQs. Since it is possible for a GPIO to be requested
 84	 * as both a GPIO and an IRQ, we need to ensure that we don't lock it
 85	 * too early.
 86	 */
 87	u8 gpio_unlock_count[GPIO_PER_BANK];
 88	/* Used in the interrupt handler */
 89	struct bcm_kona_gpio *kona_gpio;
 90};
 91
 92static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
 93						int bank_id, u32 lockcode)
 94{
 95	writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
 96	writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
 97}
 98
 99static void bcm_kona_gpio_lock_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	int bit = GPIO_BIT(gpio);
106	struct bcm_kona_gpio_bank *bank = &kona_gpio->banks[bank_id];
107
108	if (bank->gpio_unlock_count[bit] == 0) {
109		dev_err(kona_gpio->gpio_chip.parent,
110			"Unbalanced locks for GPIO %u\n", gpio);
111		return;
112	}
113
114	if (--bank->gpio_unlock_count[bit] == 0) {
115		raw_spin_lock_irqsave(&kona_gpio->lock, flags);
 
116
117		val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
118		val |= BIT(bit);
119		bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
120
121		raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
122	}
123}
124
125static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
126					unsigned gpio)
127{
128	u32 val;
129	unsigned long flags;
130	int bank_id = GPIO_BANK(gpio);
131	int bit = GPIO_BIT(gpio);
132	struct bcm_kona_gpio_bank *bank = &kona_gpio->banks[bank_id];
133
134	if (bank->gpio_unlock_count[bit] == 0) {
135		raw_spin_lock_irqsave(&kona_gpio->lock, flags);
136
137		val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
138		val &= ~BIT(bit);
139		bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
140
141		raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
142	}
143
144	++bank->gpio_unlock_count[bit];
145}
146
147static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
148{
149	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
150	void __iomem *reg_base = kona_gpio->reg_base;
151	u32 val;
152
153	val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
154	return val ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
155}
156
157static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
158{
159	struct bcm_kona_gpio *kona_gpio;
160	void __iomem *reg_base;
161	int bank_id = GPIO_BANK(gpio);
162	int bit = GPIO_BIT(gpio);
163	u32 val, reg_offset;
164	unsigned long flags;
165
166	kona_gpio = gpiochip_get_data(chip);
167	reg_base = kona_gpio->reg_base;
168	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
169
170	/* this function only applies to output pin */
171	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
172		goto out;
173
174	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
175
176	val = readl(reg_base + reg_offset);
177	val |= BIT(bit);
178	writel(val, reg_base + reg_offset);
179
180out:
181	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
182}
183
184static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
185{
186	struct bcm_kona_gpio *kona_gpio;
187	void __iomem *reg_base;
188	int bank_id = GPIO_BANK(gpio);
189	int bit = GPIO_BIT(gpio);
190	u32 val, reg_offset;
191	unsigned long flags;
192
193	kona_gpio = gpiochip_get_data(chip);
194	reg_base = kona_gpio->reg_base;
195	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
196
197	if (bcm_kona_gpio_get_dir(chip, gpio) == GPIO_LINE_DIRECTION_IN)
198		reg_offset = GPIO_IN_STATUS(bank_id);
199	else
200		reg_offset = GPIO_OUT_STATUS(bank_id);
201
202	/* read the GPIO bank status */
203	val = readl(reg_base + reg_offset);
204
205	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
206
207	/* return the specified bit status */
208	return !!(val & BIT(bit));
209}
210
211static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
212{
213	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
214
215	bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
216	return 0;
217}
218
219static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
220{
221	struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
222
223	bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
224}
225
226static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
227{
228	struct bcm_kona_gpio *kona_gpio;
229	void __iomem *reg_base;
230	u32 val;
231	unsigned long flags;
232
233	kona_gpio = gpiochip_get_data(chip);
234	reg_base = kona_gpio->reg_base;
235	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
236
237	val = readl(reg_base + GPIO_CONTROL(gpio));
238	val &= ~GPIO_GPCTR0_IOTR_MASK;
239	val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
240	writel(val, reg_base + GPIO_CONTROL(gpio));
241
242	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
243
244	return 0;
245}
246
247static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
248					  unsigned gpio, int value)
249{
250	struct bcm_kona_gpio *kona_gpio;
251	void __iomem *reg_base;
252	int bank_id = GPIO_BANK(gpio);
253	int bit = GPIO_BIT(gpio);
254	u32 val, reg_offset;
255	unsigned long flags;
256
257	kona_gpio = gpiochip_get_data(chip);
258	reg_base = kona_gpio->reg_base;
259	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
260
261	val = readl(reg_base + GPIO_CONTROL(gpio));
262	val &= ~GPIO_GPCTR0_IOTR_MASK;
263	val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT;
264	writel(val, reg_base + GPIO_CONTROL(gpio));
265	reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
266
267	val = readl(reg_base + reg_offset);
268	val |= BIT(bit);
269	writel(val, reg_base + reg_offset);
270
271	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
272
273	return 0;
274}
275
276static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
277{
278	struct bcm_kona_gpio *kona_gpio;
279
280	kona_gpio = gpiochip_get_data(chip);
281	if (gpio >= kona_gpio->gpio_chip.ngpio)
282		return -ENXIO;
283	return irq_create_mapping(kona_gpio->irq_domain, gpio);
284}
285
286static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
287				      unsigned debounce)
288{
289	struct bcm_kona_gpio *kona_gpio;
290	void __iomem *reg_base;
291	u32 val, res;
292	unsigned long flags;
293
294	kona_gpio = gpiochip_get_data(chip);
295	reg_base = kona_gpio->reg_base;
296	/* debounce must be 1-128ms (or 0) */
297	if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
298		dev_err(chip->parent, "Debounce value %u not in range\n",
299			debounce);
300		return -EINVAL;
301	}
302
303	/* calculate debounce bit value */
304	if (debounce != 0) {
305		/* Convert to ms */
306		debounce /= 1000;
307		/* find the MSB */
308		res = fls(debounce) - 1;
309		/* Check if MSB-1 is set (round up or down) */
310		if (res > 0 && (debounce & BIT(res - 1)))
311			res++;
312	}
313
314	/* spin lock for read-modify-write of the GPIO register */
315	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
316
317	val = readl(reg_base + GPIO_CONTROL(gpio));
318	val &= ~GPIO_GPCTR0_DBR_MASK;
319
320	if (debounce == 0) {
321		/* disable debounce */
322		val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
323	} else {
324		val |= GPIO_GPCTR0_DB_ENABLE_MASK |
325		    (res << GPIO_GPCTR0_DBR_SHIFT);
326	}
327
328	writel(val, reg_base + GPIO_CONTROL(gpio));
329
330	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
331
332	return 0;
333}
334
335static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
336				    unsigned long config)
337{
338	u32 debounce;
339
340	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
341		return -ENOTSUPP;
342
343	debounce = pinconf_to_config_argument(config);
344	return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
345}
346
347static const struct gpio_chip template_chip = {
348	.label = "bcm-kona-gpio",
349	.owner = THIS_MODULE,
350	.request = bcm_kona_gpio_request,
351	.free = bcm_kona_gpio_free,
352	.get_direction = bcm_kona_gpio_get_dir,
353	.direction_input = bcm_kona_gpio_direction_input,
354	.get = bcm_kona_gpio_get,
355	.direction_output = bcm_kona_gpio_direction_output,
356	.set = bcm_kona_gpio_set,
357	.set_config = bcm_kona_gpio_set_config,
358	.to_irq = bcm_kona_gpio_to_irq,
359	.base = 0,
360};
361
362static void bcm_kona_gpio_irq_ack(struct irq_data *d)
363{
364	struct bcm_kona_gpio *kona_gpio;
365	void __iomem *reg_base;
366	unsigned gpio = d->hwirq;
367	int bank_id = GPIO_BANK(gpio);
368	int bit = GPIO_BIT(gpio);
369	u32 val;
370	unsigned long flags;
371
372	kona_gpio = irq_data_get_irq_chip_data(d);
373	reg_base = kona_gpio->reg_base;
374	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
375
376	val = readl(reg_base + GPIO_INT_STATUS(bank_id));
377	val |= BIT(bit);
378	writel(val, reg_base + GPIO_INT_STATUS(bank_id));
379
380	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
381}
382
383static void bcm_kona_gpio_irq_mask(struct irq_data *d)
384{
385	struct bcm_kona_gpio *kona_gpio;
386	void __iomem *reg_base;
387	unsigned gpio = d->hwirq;
388	int bank_id = GPIO_BANK(gpio);
389	int bit = GPIO_BIT(gpio);
390	u32 val;
391	unsigned long flags;
392
393	kona_gpio = irq_data_get_irq_chip_data(d);
394	reg_base = kona_gpio->reg_base;
395
396	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
397
398	val = readl(reg_base + GPIO_INT_MASK(bank_id));
399	val |= BIT(bit);
400	writel(val, reg_base + GPIO_INT_MASK(bank_id));
401	gpiochip_disable_irq(&kona_gpio->gpio_chip, gpio);
402
403	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
404}
405
406static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
407{
408	struct bcm_kona_gpio *kona_gpio;
409	void __iomem *reg_base;
410	unsigned gpio = d->hwirq;
411	int bank_id = GPIO_BANK(gpio);
412	int bit = GPIO_BIT(gpio);
413	u32 val;
414	unsigned long flags;
415
416	kona_gpio = irq_data_get_irq_chip_data(d);
417	reg_base = kona_gpio->reg_base;
418
419	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
420
421	val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
422	val |= BIT(bit);
423	writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
424	gpiochip_enable_irq(&kona_gpio->gpio_chip, gpio);
425
426	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
427}
428
429static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
430{
431	struct bcm_kona_gpio *kona_gpio;
432	void __iomem *reg_base;
433	unsigned gpio = d->hwirq;
434	u32 lvl_type;
435	u32 val;
436	unsigned long flags;
437
438	kona_gpio = irq_data_get_irq_chip_data(d);
439	reg_base = kona_gpio->reg_base;
440	switch (type & IRQ_TYPE_SENSE_MASK) {
441	case IRQ_TYPE_EDGE_RISING:
442		lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
443		break;
444
445	case IRQ_TYPE_EDGE_FALLING:
446		lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
447		break;
448
449	case IRQ_TYPE_EDGE_BOTH:
450		lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
451		break;
452
453	case IRQ_TYPE_LEVEL_HIGH:
454	case IRQ_TYPE_LEVEL_LOW:
455		/* BCM GPIO doesn't support level triggering */
456	default:
457		dev_err(kona_gpio->gpio_chip.parent,
458			"Invalid BCM GPIO irq type 0x%x\n", type);
459		return -EINVAL;
460	}
461
462	raw_spin_lock_irqsave(&kona_gpio->lock, flags);
463
464	val = readl(reg_base + GPIO_CONTROL(gpio));
465	val &= ~GPIO_GPCTR0_ITR_MASK;
466	val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
467	writel(val, reg_base + GPIO_CONTROL(gpio));
468
469	raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
470
471	return 0;
472}
473
474static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
475{
476	void __iomem *reg_base;
477	int bit, bank_id;
478	unsigned long sta;
479	struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
480	struct irq_chip *chip = irq_desc_get_chip(desc);
481
482	chained_irq_enter(chip, desc);
483
484	/*
485	 * For bank interrupts, we can't use chip_data to store the kona_gpio
486	 * pointer, since GIC needs it for its own purposes. Therefore, we get
487	 * our pointer from the bank structure.
488	 */
489	reg_base = bank->kona_gpio->reg_base;
490	bank_id = bank->id;
491
492	while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
493		    (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
494		for_each_set_bit(bit, &sta, 32) {
495			int hwirq = GPIO_PER_BANK * bank_id + bit;
496			/*
497			 * Clear interrupt before handler is called so we don't
498			 * miss any interrupt occurred during executing them.
499			 */
500			writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
501			       BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
502			/* Invoke interrupt handler */
503			generic_handle_domain_irq(bank->kona_gpio->irq_domain,
504						  hwirq);
505		}
506	}
507
508	chained_irq_exit(chip, desc);
509}
510
511static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
512{
513	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
514	unsigned int gpio = d->hwirq;
515
516	/*
517	 * We need to unlock the GPIO before any other operations are performed
518	 * on the relevant GPIO configuration registers
519	 */
520	bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
521
522	return gpiochip_reqres_irq(&kona_gpio->gpio_chip, gpio);
523}
524
525static void bcm_kona_gpio_irq_relres(struct irq_data *d)
526{
527	struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
528	unsigned int gpio = d->hwirq;
529
530	/* Once we no longer use it, lock the GPIO again */
531	bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
532
533	gpiochip_relres_irq(&kona_gpio->gpio_chip, gpio);
534}
535
536static struct irq_chip bcm_gpio_irq_chip = {
537	.name = "bcm-kona-gpio",
538	.irq_ack = bcm_kona_gpio_irq_ack,
539	.irq_mask = bcm_kona_gpio_irq_mask,
540	.irq_unmask = bcm_kona_gpio_irq_unmask,
541	.irq_set_type = bcm_kona_gpio_irq_set_type,
542	.irq_request_resources = bcm_kona_gpio_irq_reqres,
543	.irq_release_resources = bcm_kona_gpio_irq_relres,
544};
545
546static struct of_device_id const bcm_kona_gpio_of_match[] = {
547	{ .compatible = "brcm,kona-gpio" },
548	{}
549};
550
551/*
552 * This lock class tells lockdep that GPIO irqs are in a different
553 * category than their parents, so it won't report false recursion.
554 */
555static struct lock_class_key gpio_lock_class;
556static struct lock_class_key gpio_request_class;
557
558static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
559				 irq_hw_number_t hwirq)
560{
561	int ret;
562
563	ret = irq_set_chip_data(irq, d->host_data);
564	if (ret < 0)
565		return ret;
566	irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
567	irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
568	irq_set_noprobe(irq);
569
570	return 0;
571}
572
573static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
574{
575	irq_set_chip_and_handler(irq, NULL, NULL);
576	irq_set_chip_data(irq, NULL);
577}
578
579static const struct irq_domain_ops bcm_kona_irq_ops = {
580	.map = bcm_kona_gpio_irq_map,
581	.unmap = bcm_kona_gpio_irq_unmap,
582	.xlate = irq_domain_xlate_twocell,
583};
584
585static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
586{
587	void __iomem *reg_base;
588	int i;
589
590	reg_base = kona_gpio->reg_base;
591	/* disable interrupts and clear status */
592	for (i = 0; i < kona_gpio->num_bank; i++) {
593		/* Unlock the entire bank first */
594		bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
595		writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
596		writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
597		/* Now re-lock the bank */
598		bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
599	}
600}
601
602static int bcm_kona_gpio_probe(struct platform_device *pdev)
603{
604	struct device *dev = &pdev->dev;
 
605	struct bcm_kona_gpio_bank *bank;
606	struct bcm_kona_gpio *kona_gpio;
607	struct gpio_chip *chip;
608	int ret;
609	int i;
610
 
 
 
 
 
 
611	kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
612	if (!kona_gpio)
613		return -ENOMEM;
614
615	kona_gpio->gpio_chip = template_chip;
616	chip = &kona_gpio->gpio_chip;
617	ret = platform_irq_count(pdev);
618	if (!ret) {
619		dev_err(dev, "Couldn't determine # GPIO banks\n");
620		return -ENOENT;
621	} else if (ret < 0) {
622		return dev_err_probe(dev, ret, "Couldn't determine GPIO banks\n");
623	}
624	kona_gpio->num_bank = ret;
625
626	if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
627		dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
628			GPIO_MAX_BANK_NUM);
629		return -ENXIO;
630	}
631	kona_gpio->banks = devm_kcalloc(dev,
632					kona_gpio->num_bank,
633					sizeof(*kona_gpio->banks),
634					GFP_KERNEL);
635	if (!kona_gpio->banks)
636		return -ENOMEM;
637
 
 
638	chip->parent = dev;
639	chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
640
641	kona_gpio->irq_domain = irq_domain_create_linear(dev_fwnode(dev),
642							 chip->ngpio,
643							 &bcm_kona_irq_ops,
644							 kona_gpio);
645	if (!kona_gpio->irq_domain) {
646		dev_err(dev, "Couldn't allocate IRQ domain\n");
647		return -ENXIO;
648	}
649
650	kona_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
651	if (IS_ERR(kona_gpio->reg_base)) {
652		ret = PTR_ERR(kona_gpio->reg_base);
653		goto err_irq_domain;
654	}
655
656	for (i = 0; i < kona_gpio->num_bank; i++) {
657		bank = &kona_gpio->banks[i];
658		bank->id = i;
659		bank->irq = platform_get_irq(pdev, i);
660		bank->kona_gpio = kona_gpio;
661		if (bank->irq < 0) {
662			dev_err(dev, "Couldn't get IRQ for bank %d\n", i);
663			ret = -ENOENT;
664			goto err_irq_domain;
665		}
666	}
667
668	dev_info(&pdev->dev, "Setting up Kona GPIO\n");
669
670	bcm_kona_gpio_reset(kona_gpio);
671
672	ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
673	if (ret < 0) {
674		dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
675		goto err_irq_domain;
676	}
677	for (i = 0; i < kona_gpio->num_bank; i++) {
678		bank = &kona_gpio->banks[i];
679		irq_set_chained_handler_and_data(bank->irq,
680						 bcm_kona_gpio_irq_handler,
681						 bank);
682	}
683
684	raw_spin_lock_init(&kona_gpio->lock);
685
686	return 0;
687
688err_irq_domain:
689	irq_domain_remove(kona_gpio->irq_domain);
690
691	return ret;
692}
693
694static struct platform_driver bcm_kona_gpio_driver = {
695	.driver = {
696			.name = "bcm-kona-gpio",
697			.of_match_table = bcm_kona_gpio_of_match,
698	},
699	.probe = bcm_kona_gpio_probe,
700};
701builtin_platform_driver(bcm_kona_gpio_driver);