1// SPDX-License-Identifier: GPL-2.0-only
2// Copyright (C) 2015-2017 Broadcom
3
4#include <linux/bitops.h>
5#include <linux/gpio/driver.h>
6#include <linux/of.h>
7#include <linux/module.h>
8#include <linux/irqdomain.h>
9#include <linux/irqchip/chained_irq.h>
10#include <linux/interrupt.h>
11#include <linux/platform_device.h>
12
13enum gio_reg_index {
14	GIO_REG_ODEN = 0,
15	GIO_REG_DATA,
16	GIO_REG_IODIR,
17	GIO_REG_EC,
18	GIO_REG_EI,
19	GIO_REG_MASK,
20	GIO_REG_LEVEL,
21	GIO_REG_STAT,
22	NUMBER_OF_GIO_REGISTERS
23};
24
25#define GIO_BANK_SIZE           (NUMBER_OF_GIO_REGISTERS * sizeof(u32))
26#define GIO_BANK_OFF(bank, off)	(((bank) * GIO_BANK_SIZE) + (off * sizeof(u32)))
27#define GIO_ODEN(bank)          GIO_BANK_OFF(bank, GIO_REG_ODEN)
28#define GIO_DATA(bank)          GIO_BANK_OFF(bank, GIO_REG_DATA)
29#define GIO_IODIR(bank)         GIO_BANK_OFF(bank, GIO_REG_IODIR)
30#define GIO_EC(bank)            GIO_BANK_OFF(bank, GIO_REG_EC)
31#define GIO_EI(bank)            GIO_BANK_OFF(bank, GIO_REG_EI)
32#define GIO_MASK(bank)          GIO_BANK_OFF(bank, GIO_REG_MASK)
33#define GIO_LEVEL(bank)         GIO_BANK_OFF(bank, GIO_REG_LEVEL)
34#define GIO_STAT(bank)          GIO_BANK_OFF(bank, GIO_REG_STAT)
35
36struct brcmstb_gpio_bank {
37	struct list_head node;
38	int id;
39	struct gpio_chip gc;
40	struct brcmstb_gpio_priv *parent_priv;
41	u32 width;
42	u32 wake_active;
43	u32 saved_regs[GIO_REG_STAT]; /* Don't save and restore GIO_REG_STAT */
44};
45
46struct brcmstb_gpio_priv {
47	struct list_head bank_list;
48	void __iomem *reg_base;
49	struct platform_device *pdev;
50	struct irq_domain *irq_domain;
51	struct irq_chip irq_chip;
52	int parent_irq;
53	int num_gpios;
54	int parent_wake_irq;
55};
56
57#define MAX_GPIO_PER_BANK       32
58#define GPIO_BANK(gpio)         ((gpio) >> 5)
59/* assumes MAX_GPIO_PER_BANK is a multiple of 2 */
60#define GPIO_BIT(gpio)          ((gpio) & (MAX_GPIO_PER_BANK - 1))
61
62static inline struct brcmstb_gpio_priv *
63brcmstb_gpio_gc_to_priv(struct gpio_chip *gc)
64{
65	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
66	return bank->parent_priv;
67}
68
69static unsigned long
70__brcmstb_gpio_get_active_irqs(struct brcmstb_gpio_bank *bank)
71{
72	void __iomem *reg_base = bank->parent_priv->reg_base;
73
74	return bank->gc.read_reg(reg_base + GIO_STAT(bank->id)) &
75	       bank->gc.read_reg(reg_base + GIO_MASK(bank->id));
76}
77
78static unsigned long
79brcmstb_gpio_get_active_irqs(struct brcmstb_gpio_bank *bank)
80{
81	unsigned long status;
82	unsigned long flags;
83
84	raw_spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
85	status = __brcmstb_gpio_get_active_irqs(bank);
86	raw_spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
87
88	return status;
89}
90
91static int brcmstb_gpio_hwirq_to_offset(irq_hw_number_t hwirq,
92					struct brcmstb_gpio_bank *bank)
93{
94	return hwirq - bank->gc.offset;
95}
96
97static void brcmstb_gpio_set_imask(struct brcmstb_gpio_bank *bank,
98		unsigned int hwirq, bool enable)
99{
100	struct gpio_chip *gc = &bank->gc;
101	struct brcmstb_gpio_priv *priv = bank->parent_priv;
102	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(hwirq, bank));
103	u32 imask;
104	unsigned long flags;
105
106	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
107	imask = gc->read_reg(priv->reg_base + GIO_MASK(bank->id));
108	if (enable)
109		imask |= mask;
110	else
111		imask &= ~mask;
112	gc->write_reg(priv->reg_base + GIO_MASK(bank->id), imask);
113	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
114}
115
116static int brcmstb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
117{
118	struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
119	/* gc_offset is relative to this gpio_chip; want real offset */
120	int hwirq = offset + gc->offset;
121
122	if (hwirq >= priv->num_gpios)
123		return -ENXIO;
124	return irq_create_mapping(priv->irq_domain, hwirq);
125}
126
127/* -------------------- IRQ chip functions -------------------- */
128
129static void brcmstb_gpio_irq_mask(struct irq_data *d)
130{
131	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
132	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
133
134	brcmstb_gpio_set_imask(bank, d->hwirq, false);
135}
136
137static void brcmstb_gpio_irq_unmask(struct irq_data *d)
138{
139	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
140	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
141
142	brcmstb_gpio_set_imask(bank, d->hwirq, true);
143}
144
145static void brcmstb_gpio_irq_ack(struct irq_data *d)
146{
147	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
148	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
149	struct brcmstb_gpio_priv *priv = bank->parent_priv;
150	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
151
152	gc->write_reg(priv->reg_base + GIO_STAT(bank->id), mask);
153}
154
155static int brcmstb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
156{
157	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
158	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
159	struct brcmstb_gpio_priv *priv = bank->parent_priv;
160	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
161	u32 edge_insensitive, iedge_insensitive;
162	u32 edge_config, iedge_config;
163	u32 level, ilevel;
164	unsigned long flags;
165
166	switch (type) {
167	case IRQ_TYPE_LEVEL_LOW:
168		level = mask;
169		edge_config = 0;
170		edge_insensitive = 0;
171		break;
172	case IRQ_TYPE_LEVEL_HIGH:
173		level = mask;
174		edge_config = mask;
175		edge_insensitive = 0;
176		break;
177	case IRQ_TYPE_EDGE_FALLING:
178		level = 0;
179		edge_config = 0;
180		edge_insensitive = 0;
181		break;
182	case IRQ_TYPE_EDGE_RISING:
183		level = 0;
184		edge_config = mask;
185		edge_insensitive = 0;
186		break;
187	case IRQ_TYPE_EDGE_BOTH:
188		level = 0;
189		edge_config = 0;  /* don't care, but want known value */
190		edge_insensitive = mask;
191		break;
192	default:
193		return -EINVAL;
194	}
195
196	raw_spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
197
198	iedge_config = bank->gc.read_reg(priv->reg_base +
199			GIO_EC(bank->id)) & ~mask;
200	iedge_insensitive = bank->gc.read_reg(priv->reg_base +
201			GIO_EI(bank->id)) & ~mask;
202	ilevel = bank->gc.read_reg(priv->reg_base +
203			GIO_LEVEL(bank->id)) & ~mask;
204
205	bank->gc.write_reg(priv->reg_base + GIO_EC(bank->id),
206			iedge_config | edge_config);
207	bank->gc.write_reg(priv->reg_base + GIO_EI(bank->id),
208			iedge_insensitive | edge_insensitive);
209	bank->gc.write_reg(priv->reg_base + GIO_LEVEL(bank->id),
210			ilevel | level);
211
212	raw_spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
213	return 0;
214}
215
216static int brcmstb_gpio_priv_set_wake(struct brcmstb_gpio_priv *priv,
217		unsigned int enable)
218{
219	int ret = 0;
220
221	if (enable)
222		ret = enable_irq_wake(priv->parent_wake_irq);
223	else
224		ret = disable_irq_wake(priv->parent_wake_irq);
225	if (ret)
226		dev_err(&priv->pdev->dev, "failed to %s wake-up interrupt\n",
227				enable ? "enable" : "disable");
228	return ret;
229}
230
231static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
232{
233	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
234	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
235	struct brcmstb_gpio_priv *priv = bank->parent_priv;
236	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
237
238	/*
239	 * Do not do anything specific for now, suspend/resume callbacks will
240	 * configure the interrupt mask appropriately
241	 */
242	if (enable)
243		bank->wake_active |= mask;
244	else
245		bank->wake_active &= ~mask;
246
247	return brcmstb_gpio_priv_set_wake(priv, enable);
248}
249
250static irqreturn_t brcmstb_gpio_wake_irq_handler(int irq, void *data)
251{
252	struct brcmstb_gpio_priv *priv = data;
253
254	if (!priv || irq != priv->parent_wake_irq)
255		return IRQ_NONE;
256
257	/* Nothing to do */
258	return IRQ_HANDLED;
259}
260
261static void brcmstb_gpio_irq_bank_handler(struct brcmstb_gpio_bank *bank)
262{
263	struct brcmstb_gpio_priv *priv = bank->parent_priv;
264	struct irq_domain *domain = priv->irq_domain;
265	int hwbase = bank->gc.offset;
266	unsigned long status;
267
268	while ((status = brcmstb_gpio_get_active_irqs(bank))) {
269		unsigned int offset;
270
271		for_each_set_bit(offset, &status, 32) {
272			if (offset >= bank->width)
273				dev_warn(&priv->pdev->dev,
274					 "IRQ for invalid GPIO (bank=%d, offset=%d)\n",
275					 bank->id, offset);
276			generic_handle_domain_irq(domain, hwbase + offset);
277		}
278	}
279}
280
281/* Each UPG GIO block has one IRQ for all banks */
282static void brcmstb_gpio_irq_handler(struct irq_desc *desc)
283{
284	struct brcmstb_gpio_priv *priv = irq_desc_get_handler_data(desc);
285	struct irq_chip *chip = irq_desc_get_chip(desc);
286	struct brcmstb_gpio_bank *bank;
287
288	/* Interrupts weren't properly cleared during probe */
289	BUG_ON(!priv || !chip);
290
291	chained_irq_enter(chip, desc);
292	list_for_each_entry(bank, &priv->bank_list, node)
293		brcmstb_gpio_irq_bank_handler(bank);
294	chained_irq_exit(chip, desc);
295}
296
297static struct brcmstb_gpio_bank *brcmstb_gpio_hwirq_to_bank(
298		struct brcmstb_gpio_priv *priv, irq_hw_number_t hwirq)
299{
300	struct brcmstb_gpio_bank *bank;
301	int i = 0;
302
303	/* banks are in descending order */
304	list_for_each_entry_reverse(bank, &priv->bank_list, node) {
305		i += bank->gc.ngpio;
306		if (hwirq < i)
307			return bank;
308	}
309	return NULL;
310}
311
312/*
313 * This lock class tells lockdep that GPIO irqs are in a different
314 * category than their parents, so it won't report false recursion.
315 */
316static struct lock_class_key brcmstb_gpio_irq_lock_class;
317static struct lock_class_key brcmstb_gpio_irq_request_class;
318
319
320static int brcmstb_gpio_irq_map(struct irq_domain *d, unsigned int irq,
321		irq_hw_number_t hwirq)
322{
323	struct brcmstb_gpio_priv *priv = d->host_data;
324	struct brcmstb_gpio_bank *bank =
325		brcmstb_gpio_hwirq_to_bank(priv, hwirq);
326	struct platform_device *pdev = priv->pdev;
327	int ret;
328
329	if (!bank)
330		return -EINVAL;
331
332	dev_dbg(&pdev->dev, "Mapping irq %d for gpio line %d (bank %d)\n",
333		irq, (int)hwirq, bank->id);
334	ret = irq_set_chip_data(irq, &bank->gc);
335	if (ret < 0)
336		return ret;
337	irq_set_lockdep_class(irq, &brcmstb_gpio_irq_lock_class,
338			      &brcmstb_gpio_irq_request_class);
339	irq_set_chip_and_handler(irq, &priv->irq_chip, handle_level_irq);
340	irq_set_noprobe(irq);
341	return 0;
342}
343
344static void brcmstb_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
345{
346	irq_set_chip_and_handler(irq, NULL, NULL);
347	irq_set_chip_data(irq, NULL);
348}
349
350static const struct irq_domain_ops brcmstb_gpio_irq_domain_ops = {
351	.map = brcmstb_gpio_irq_map,
352	.unmap = brcmstb_gpio_irq_unmap,
353	.xlate = irq_domain_xlate_twocell,
354};
355
356/* Make sure that the number of banks matches up between properties */
357static int brcmstb_gpio_sanity_check_banks(struct device *dev,
358		struct device_node *np, struct resource *res)
359{
360	int res_num_banks = resource_size(res) / GIO_BANK_SIZE;
361	int num_banks =
362		of_property_count_u32_elems(np, "brcm,gpio-bank-widths");
363
364	if (res_num_banks != num_banks) {
365		dev_err(dev, "Mismatch in banks: res had %d, bank-widths had %d\n",
366				res_num_banks, num_banks);
367		return -EINVAL;
368	} else {
369		return 0;
370	}
371}
372
373static void brcmstb_gpio_remove(struct platform_device *pdev)
374{
375	struct brcmstb_gpio_priv *priv = platform_get_drvdata(pdev);
376	struct brcmstb_gpio_bank *bank;
377	int offset, virq;
378
379	if (priv->parent_irq > 0)
380		irq_set_chained_handler_and_data(priv->parent_irq, NULL, NULL);
381
382	/* Remove all IRQ mappings and delete the domain */
383	if (priv->irq_domain) {
384		for (offset = 0; offset < priv->num_gpios; offset++) {
385			virq = irq_find_mapping(priv->irq_domain, offset);
386			irq_dispose_mapping(virq);
387		}
388		irq_domain_remove(priv->irq_domain);
389	}
390
391	/*
392	 * You can lose return values below, but we report all errors, and it's
393	 * more important to actually perform all of the steps.
394	 */
395	list_for_each_entry(bank, &priv->bank_list, node)
396		gpiochip_remove(&bank->gc);
397}
398
399static int brcmstb_gpio_of_xlate(struct gpio_chip *gc,
400		const struct of_phandle_args *gpiospec, u32 *flags)
401{
402	struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
403	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
404	int offset;
405
406	if (gc->of_gpio_n_cells != 2) {
407		WARN_ON(1);
408		return -EINVAL;
409	}
410
411	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
412		return -EINVAL;
413
414	offset = gpiospec->args[0] - bank->gc.offset;
415	if (offset >= gc->ngpio || offset < 0)
416		return -EINVAL;
417
418	if (unlikely(offset >= bank->width)) {
419		dev_warn_ratelimited(&priv->pdev->dev,
420			"Received request for invalid GPIO offset %d\n",
421			gpiospec->args[0]);
422	}
423
424	if (flags)
425		*flags = gpiospec->args[1];
426
427	return offset;
428}
429
430/* priv->parent_irq and priv->num_gpios must be set before calling */
431static int brcmstb_gpio_irq_setup(struct platform_device *pdev,
432		struct brcmstb_gpio_priv *priv)
433{
434	struct device *dev = &pdev->dev;
435	struct device_node *np = dev->of_node;
436	int err;
437
438	priv->irq_domain =
439		irq_domain_add_linear(np, priv->num_gpios,
440				      &brcmstb_gpio_irq_domain_ops,
441				      priv);
442	if (!priv->irq_domain) {
443		dev_err(dev, "Couldn't allocate IRQ domain\n");
444		return -ENXIO;
445	}
446
447	if (of_property_read_bool(np, "wakeup-source")) {
448		priv->parent_wake_irq = platform_get_irq(pdev, 1);
449		if (priv->parent_wake_irq < 0) {
450			priv->parent_wake_irq = 0;
451			dev_warn(dev,
452				"Couldn't get wake IRQ - GPIOs will not be able to wake from sleep");
453		} else {
454			/*
455			 * Set wakeup capability so we can process boot-time
456			 * "wakeups" (e.g., from S5 cold boot)
457			 */
458			device_set_wakeup_capable(dev, true);
459			device_wakeup_enable(dev);
460			err = devm_request_irq(dev, priv->parent_wake_irq,
461					       brcmstb_gpio_wake_irq_handler,
462					       IRQF_SHARED,
463					       "brcmstb-gpio-wake", priv);
464
465			if (err < 0) {
466				dev_err(dev, "Couldn't request wake IRQ");
467				goto out_free_domain;
468			}
469		}
470	}
471
472	priv->irq_chip.name = dev_name(dev);
473	priv->irq_chip.irq_disable = brcmstb_gpio_irq_mask;
474	priv->irq_chip.irq_mask = brcmstb_gpio_irq_mask;
475	priv->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask;
476	priv->irq_chip.irq_ack = brcmstb_gpio_irq_ack;
477	priv->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type;
478
479	if (priv->parent_wake_irq)
480		priv->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake;
481
482	irq_set_chained_handler_and_data(priv->parent_irq,
483					 brcmstb_gpio_irq_handler, priv);
484	irq_set_status_flags(priv->parent_irq, IRQ_DISABLE_UNLAZY);
485
486	return 0;
487
488out_free_domain:
489	irq_domain_remove(priv->irq_domain);
490
491	return err;
492}
493
494static void brcmstb_gpio_bank_save(struct brcmstb_gpio_priv *priv,
495				   struct brcmstb_gpio_bank *bank)
496{
497	struct gpio_chip *gc = &bank->gc;
498	unsigned int i;
499
500	for (i = 0; i < GIO_REG_STAT; i++)
501		bank->saved_regs[i] = gc->read_reg(priv->reg_base +
502						   GIO_BANK_OFF(bank->id, i));
503}
504
505static void brcmstb_gpio_quiesce(struct device *dev, bool save)
506{
507	struct brcmstb_gpio_priv *priv = dev_get_drvdata(dev);
508	struct brcmstb_gpio_bank *bank;
509	struct gpio_chip *gc;
510	u32 imask;
511
512	/* disable non-wake interrupt */
513	if (priv->parent_irq >= 0)
514		disable_irq(priv->parent_irq);
515
516	list_for_each_entry(bank, &priv->bank_list, node) {
517		gc = &bank->gc;
518
519		if (save)
520			brcmstb_gpio_bank_save(priv, bank);
521
522		/* Unmask GPIOs which have been flagged as wake-up sources */
523		if (priv->parent_wake_irq)
524			imask = bank->wake_active;
525		else
526			imask = 0;
527		gc->write_reg(priv->reg_base + GIO_MASK(bank->id),
528			       imask);
529	}
530}
531
532static void brcmstb_gpio_shutdown(struct platform_device *pdev)
533{
534	/* Enable GPIO for S5 cold boot */
535	brcmstb_gpio_quiesce(&pdev->dev, false);
536}
537
538#ifdef CONFIG_PM_SLEEP
539static void brcmstb_gpio_bank_restore(struct brcmstb_gpio_priv *priv,
540				      struct brcmstb_gpio_bank *bank)
541{
542	struct gpio_chip *gc = &bank->gc;
543	unsigned int i;
544
545	for (i = 0; i < GIO_REG_STAT; i++)
546		gc->write_reg(priv->reg_base + GIO_BANK_OFF(bank->id, i),
547			      bank->saved_regs[i]);
548}
549
550static int brcmstb_gpio_suspend(struct device *dev)
551{
552	brcmstb_gpio_quiesce(dev, true);
553	return 0;
554}
555
556static int brcmstb_gpio_resume(struct device *dev)
557{
558	struct brcmstb_gpio_priv *priv = dev_get_drvdata(dev);
559	struct brcmstb_gpio_bank *bank;
560	bool need_wakeup_event = false;
561
562	list_for_each_entry(bank, &priv->bank_list, node) {
563		need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank);
564		brcmstb_gpio_bank_restore(priv, bank);
565	}
566
567	if (priv->parent_wake_irq && need_wakeup_event)
568		pm_wakeup_event(dev, 0);
569
570	/* enable non-wake interrupt */
571	if (priv->parent_irq >= 0)
572		enable_irq(priv->parent_irq);
573
574	return 0;
575}
576
577#else
578#define brcmstb_gpio_suspend	NULL
579#define brcmstb_gpio_resume	NULL
580#endif /* CONFIG_PM_SLEEP */
581
582static const struct dev_pm_ops brcmstb_gpio_pm_ops = {
583	.suspend_noirq	= brcmstb_gpio_suspend,
584	.resume_noirq = brcmstb_gpio_resume,
585};
586
587static int brcmstb_gpio_probe(struct platform_device *pdev)
588{
589	struct device *dev = &pdev->dev;
590	struct device_node *np = dev->of_node;
591	void __iomem *reg_base;
592	struct brcmstb_gpio_priv *priv;
593	struct resource *res;
594	struct property *prop;
595	const __be32 *p;
596	u32 bank_width;
597	int num_banks = 0;
598	int num_gpios = 0;
599	int err;
600	unsigned long flags = 0;
601	bool need_wakeup_event = false;
602
603	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
604	if (!priv)
605		return -ENOMEM;
606	platform_set_drvdata(pdev, priv);
607	INIT_LIST_HEAD(&priv->bank_list);
608
609	reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
610	if (IS_ERR(reg_base))
611		return PTR_ERR(reg_base);
612
613	priv->reg_base = reg_base;
614	priv->pdev = pdev;
615
616	if (of_property_read_bool(np, "interrupt-controller")) {
617		priv->parent_irq = platform_get_irq(pdev, 0);
618		if (priv->parent_irq <= 0)
619			return -ENOENT;
620	} else {
621		priv->parent_irq = -ENOENT;
622	}
623
624	if (brcmstb_gpio_sanity_check_banks(dev, np, res))
625		return -EINVAL;
626
627	/*
628	 * MIPS endianness is configured by boot strap, which also reverses all
629	 * bus endianness (i.e., big-endian CPU + big endian bus ==> native
630	 * endian I/O).
631	 *
632	 * Other architectures (e.g., ARM) either do not support big endian, or
633	 * else leave I/O in little endian mode.
634	 */
635#if defined(CONFIG_MIPS) && defined(__BIG_ENDIAN)
636	flags = BGPIOF_BIG_ENDIAN_BYTE_ORDER;
637#endif
638
639	of_property_for_each_u32(np, "brcm,gpio-bank-widths", prop, p,
640			bank_width) {
641		struct brcmstb_gpio_bank *bank;
642		struct gpio_chip *gc;
643
644		/*
645		 * If bank_width is 0, then there is an empty bank in the
646		 * register block. Special handling for this case.
647		 */
648		if (bank_width == 0) {
649			dev_dbg(dev, "Width 0 found: Empty bank @ %d\n",
650				num_banks);
651			num_banks++;
652			num_gpios += MAX_GPIO_PER_BANK;
653			continue;
654		}
655
656		bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);
657		if (!bank) {
658			err = -ENOMEM;
659			goto fail;
660		}
661
662		bank->parent_priv = priv;
663		bank->id = num_banks;
664		if (bank_width <= 0 || bank_width > MAX_GPIO_PER_BANK) {
665			dev_err(dev, "Invalid bank width %d\n", bank_width);
666			err = -EINVAL;
667			goto fail;
668		} else {
669			bank->width = bank_width;
670		}
671
672		/*
673		 * Regs are 4 bytes wide, have data reg, no set/clear regs,
674		 * and direction bits have 0 = output and 1 = input
675		 */
676		gc = &bank->gc;
677		err = bgpio_init(gc, dev, 4,
678				reg_base + GIO_DATA(bank->id),
679				NULL, NULL, NULL,
680				reg_base + GIO_IODIR(bank->id), flags);
681		if (err) {
682			dev_err(dev, "bgpio_init() failed\n");
683			goto fail;
684		}
685
686		gc->owner = THIS_MODULE;
687		gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", np);
688		if (!gc->label) {
689			err = -ENOMEM;
690			goto fail;
691		}
692		gc->of_gpio_n_cells = 2;
693		gc->of_xlate = brcmstb_gpio_of_xlate;
694		/* not all ngpio lines are valid, will use bank width later */
695		gc->ngpio = MAX_GPIO_PER_BANK;
696		gc->offset = bank->id * MAX_GPIO_PER_BANK;
697		gc->request = gpiochip_generic_request;
698		gc->free = gpiochip_generic_free;
699		if (priv->parent_irq > 0)
700			gc->to_irq = brcmstb_gpio_to_irq;
701
702		/*
703		 * Mask all interrupts by default, since wakeup interrupts may
704		 * be retained from S5 cold boot
705		 */
706		need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank);
707		gc->write_reg(reg_base + GIO_MASK(bank->id), 0);
708
709		err = gpiochip_add_data(gc, bank);
710		if (err) {
711			dev_err(dev, "Could not add gpiochip for bank %d\n",
712					bank->id);
713			goto fail;
714		}
715		num_gpios += gc->ngpio;
716
717		dev_dbg(dev, "bank=%d, base=%d, ngpio=%d, width=%d\n", bank->id,
718			gc->base, gc->ngpio, bank->width);
719
720		/* Everything looks good, so add bank to list */
721		list_add(&bank->node, &priv->bank_list);
722
723		num_banks++;
724	}
725
726	priv->num_gpios = num_gpios;
727	if (priv->parent_irq > 0) {
728		err = brcmstb_gpio_irq_setup(pdev, priv);
729		if (err)
730			goto fail;
731	}
732
733	if (priv->parent_wake_irq && need_wakeup_event)
734		pm_wakeup_event(dev, 0);
735
736	return 0;
737
738fail:
739	(void) brcmstb_gpio_remove(pdev);
740	return err;
741}
742
743static const struct of_device_id brcmstb_gpio_of_match[] = {
744	{ .compatible = "brcm,brcmstb-gpio" },
745	{},
746};
747
748MODULE_DEVICE_TABLE(of, brcmstb_gpio_of_match);
749
750static struct platform_driver brcmstb_gpio_driver = {
751	.driver = {
752		.name = "brcmstb-gpio",
753		.of_match_table = brcmstb_gpio_of_match,
754		.pm = &brcmstb_gpio_pm_ops,
755	},
756	.probe = brcmstb_gpio_probe,
757	.remove_new = brcmstb_gpio_remove,
758	.shutdown = brcmstb_gpio_shutdown,
759};
760module_platform_driver(brcmstb_gpio_driver);
761
762MODULE_AUTHOR("Gregory Fong");
763MODULE_DESCRIPTION("Driver for Broadcom BRCMSTB SoC UPG GPIO");
764MODULE_LICENSE("GPL v2");
765