xref: /linux/drivers/gpio/gpio-brcmstb.c (revision 8a79db5e83a5d52c74e6f3c40d6f312cf899213e)
1 /*
2  * Copyright (C) 2015-2017 Broadcom
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation version 2.
7  *
8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9  * kind, whether express or implied; without even the implied warranty
10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 #include <linux/bitops.h>
15 #include <linux/gpio/driver.h>
16 #include <linux/of_device.h>
17 #include <linux/of_irq.h>
18 #include <linux/module.h>
19 #include <linux/irqdomain.h>
20 #include <linux/irqchip/chained_irq.h>
21 #include <linux/interrupt.h>
22 
23 enum gio_reg_index {
24 	GIO_REG_ODEN = 0,
25 	GIO_REG_DATA,
26 	GIO_REG_IODIR,
27 	GIO_REG_EC,
28 	GIO_REG_EI,
29 	GIO_REG_MASK,
30 	GIO_REG_LEVEL,
31 	GIO_REG_STAT,
32 	NUMBER_OF_GIO_REGISTERS
33 };
34 
35 #define GIO_BANK_SIZE           (NUMBER_OF_GIO_REGISTERS * sizeof(u32))
36 #define GIO_BANK_OFF(bank, off)	(((bank) * GIO_BANK_SIZE) + (off * sizeof(u32)))
37 #define GIO_ODEN(bank)          GIO_BANK_OFF(bank, GIO_REG_ODEN)
38 #define GIO_DATA(bank)          GIO_BANK_OFF(bank, GIO_REG_DATA)
39 #define GIO_IODIR(bank)         GIO_BANK_OFF(bank, GIO_REG_IODIR)
40 #define GIO_EC(bank)            GIO_BANK_OFF(bank, GIO_REG_EC)
41 #define GIO_EI(bank)            GIO_BANK_OFF(bank, GIO_REG_EI)
42 #define GIO_MASK(bank)          GIO_BANK_OFF(bank, GIO_REG_MASK)
43 #define GIO_LEVEL(bank)         GIO_BANK_OFF(bank, GIO_REG_LEVEL)
44 #define GIO_STAT(bank)          GIO_BANK_OFF(bank, GIO_REG_STAT)
45 
46 struct brcmstb_gpio_bank {
47 	struct list_head node;
48 	int id;
49 	struct gpio_chip gc;
50 	struct brcmstb_gpio_priv *parent_priv;
51 	u32 width;
52 	u32 wake_active;
53 	u32 saved_regs[GIO_REG_STAT]; /* Don't save and restore GIO_REG_STAT */
54 };
55 
56 struct brcmstb_gpio_priv {
57 	struct list_head bank_list;
58 	void __iomem *reg_base;
59 	struct platform_device *pdev;
60 	struct irq_domain *irq_domain;
61 	struct irq_chip irq_chip;
62 	int parent_irq;
63 	int gpio_base;
64 	int num_gpios;
65 	int parent_wake_irq;
66 };
67 
68 #define MAX_GPIO_PER_BANK       32
69 #define GPIO_BANK(gpio)         ((gpio) >> 5)
70 /* assumes MAX_GPIO_PER_BANK is a multiple of 2 */
71 #define GPIO_BIT(gpio)          ((gpio) & (MAX_GPIO_PER_BANK - 1))
72 
73 static inline struct brcmstb_gpio_priv *
74 brcmstb_gpio_gc_to_priv(struct gpio_chip *gc)
75 {
76 	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
77 	return bank->parent_priv;
78 }
79 
80 static unsigned long
81 __brcmstb_gpio_get_active_irqs(struct brcmstb_gpio_bank *bank)
82 {
83 	void __iomem *reg_base = bank->parent_priv->reg_base;
84 
85 	return bank->gc.read_reg(reg_base + GIO_STAT(bank->id)) &
86 	       bank->gc.read_reg(reg_base + GIO_MASK(bank->id));
87 }
88 
89 static unsigned long
90 brcmstb_gpio_get_active_irqs(struct brcmstb_gpio_bank *bank)
91 {
92 	unsigned long status;
93 	unsigned long flags;
94 
95 	spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
96 	status = __brcmstb_gpio_get_active_irqs(bank);
97 	spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
98 
99 	return status;
100 }
101 
102 static int brcmstb_gpio_hwirq_to_offset(irq_hw_number_t hwirq,
103 					struct brcmstb_gpio_bank *bank)
104 {
105 	return hwirq - (bank->gc.base - bank->parent_priv->gpio_base);
106 }
107 
108 static void brcmstb_gpio_set_imask(struct brcmstb_gpio_bank *bank,
109 		unsigned int hwirq, bool enable)
110 {
111 	struct gpio_chip *gc = &bank->gc;
112 	struct brcmstb_gpio_priv *priv = bank->parent_priv;
113 	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(hwirq, bank));
114 	u32 imask;
115 	unsigned long flags;
116 
117 	spin_lock_irqsave(&gc->bgpio_lock, flags);
118 	imask = gc->read_reg(priv->reg_base + GIO_MASK(bank->id));
119 	if (enable)
120 		imask |= mask;
121 	else
122 		imask &= ~mask;
123 	gc->write_reg(priv->reg_base + GIO_MASK(bank->id), imask);
124 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
125 }
126 
127 static int brcmstb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
128 {
129 	struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
130 	/* gc_offset is relative to this gpio_chip; want real offset */
131 	int hwirq = offset + (gc->base - priv->gpio_base);
132 
133 	if (hwirq >= priv->num_gpios)
134 		return -ENXIO;
135 	return irq_create_mapping(priv->irq_domain, hwirq);
136 }
137 
138 /* -------------------- IRQ chip functions -------------------- */
139 
140 static void brcmstb_gpio_irq_mask(struct irq_data *d)
141 {
142 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
143 	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
144 
145 	brcmstb_gpio_set_imask(bank, d->hwirq, false);
146 }
147 
148 static void brcmstb_gpio_irq_unmask(struct irq_data *d)
149 {
150 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
151 	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
152 
153 	brcmstb_gpio_set_imask(bank, d->hwirq, true);
154 }
155 
156 static void brcmstb_gpio_irq_ack(struct irq_data *d)
157 {
158 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
159 	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
160 	struct brcmstb_gpio_priv *priv = bank->parent_priv;
161 	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
162 
163 	gc->write_reg(priv->reg_base + GIO_STAT(bank->id), mask);
164 }
165 
166 static int brcmstb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
167 {
168 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
169 	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
170 	struct brcmstb_gpio_priv *priv = bank->parent_priv;
171 	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
172 	u32 edge_insensitive, iedge_insensitive;
173 	u32 edge_config, iedge_config;
174 	u32 level, ilevel;
175 	unsigned long flags;
176 
177 	switch (type) {
178 	case IRQ_TYPE_LEVEL_LOW:
179 		level = mask;
180 		edge_config = 0;
181 		edge_insensitive = 0;
182 		break;
183 	case IRQ_TYPE_LEVEL_HIGH:
184 		level = mask;
185 		edge_config = mask;
186 		edge_insensitive = 0;
187 		break;
188 	case IRQ_TYPE_EDGE_FALLING:
189 		level = 0;
190 		edge_config = 0;
191 		edge_insensitive = 0;
192 		break;
193 	case IRQ_TYPE_EDGE_RISING:
194 		level = 0;
195 		edge_config = mask;
196 		edge_insensitive = 0;
197 		break;
198 	case IRQ_TYPE_EDGE_BOTH:
199 		level = 0;
200 		edge_config = 0;  /* don't care, but want known value */
201 		edge_insensitive = mask;
202 		break;
203 	default:
204 		return -EINVAL;
205 	}
206 
207 	spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
208 
209 	iedge_config = bank->gc.read_reg(priv->reg_base +
210 			GIO_EC(bank->id)) & ~mask;
211 	iedge_insensitive = bank->gc.read_reg(priv->reg_base +
212 			GIO_EI(bank->id)) & ~mask;
213 	ilevel = bank->gc.read_reg(priv->reg_base +
214 			GIO_LEVEL(bank->id)) & ~mask;
215 
216 	bank->gc.write_reg(priv->reg_base + GIO_EC(bank->id),
217 			iedge_config | edge_config);
218 	bank->gc.write_reg(priv->reg_base + GIO_EI(bank->id),
219 			iedge_insensitive | edge_insensitive);
220 	bank->gc.write_reg(priv->reg_base + GIO_LEVEL(bank->id),
221 			ilevel | level);
222 
223 	spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
224 	return 0;
225 }
226 
227 static int brcmstb_gpio_priv_set_wake(struct brcmstb_gpio_priv *priv,
228 		unsigned int enable)
229 {
230 	int ret = 0;
231 
232 	if (enable)
233 		ret = enable_irq_wake(priv->parent_wake_irq);
234 	else
235 		ret = disable_irq_wake(priv->parent_wake_irq);
236 	if (ret)
237 		dev_err(&priv->pdev->dev, "failed to %s wake-up interrupt\n",
238 				enable ? "enable" : "disable");
239 	return ret;
240 }
241 
242 static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
243 {
244 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
245 	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
246 	struct brcmstb_gpio_priv *priv = bank->parent_priv;
247 	u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
248 
249 	/*
250 	 * Do not do anything specific for now, suspend/resume callbacks will
251 	 * configure the interrupt mask appropriately
252 	 */
253 	if (enable)
254 		bank->wake_active |= mask;
255 	else
256 		bank->wake_active &= ~mask;
257 
258 	return brcmstb_gpio_priv_set_wake(priv, enable);
259 }
260 
261 static irqreturn_t brcmstb_gpio_wake_irq_handler(int irq, void *data)
262 {
263 	struct brcmstb_gpio_priv *priv = data;
264 
265 	if (!priv || irq != priv->parent_wake_irq)
266 		return IRQ_NONE;
267 
268 	/* Nothing to do */
269 	return IRQ_HANDLED;
270 }
271 
272 static void brcmstb_gpio_irq_bank_handler(struct brcmstb_gpio_bank *bank)
273 {
274 	struct brcmstb_gpio_priv *priv = bank->parent_priv;
275 	struct irq_domain *domain = priv->irq_domain;
276 	int hwbase = bank->gc.base - priv->gpio_base;
277 	unsigned long status;
278 
279 	while ((status = brcmstb_gpio_get_active_irqs(bank))) {
280 		unsigned int irq, offset;
281 
282 		for_each_set_bit(offset, &status, 32) {
283 			if (offset >= bank->width)
284 				dev_warn(&priv->pdev->dev,
285 					 "IRQ for invalid GPIO (bank=%d, offset=%d)\n",
286 					 bank->id, offset);
287 			irq = irq_linear_revmap(domain, hwbase + offset);
288 			generic_handle_irq(irq);
289 		}
290 	}
291 }
292 
293 /* Each UPG GIO block has one IRQ for all banks */
294 static void brcmstb_gpio_irq_handler(struct irq_desc *desc)
295 {
296 	struct brcmstb_gpio_priv *priv = irq_desc_get_handler_data(desc);
297 	struct irq_chip *chip = irq_desc_get_chip(desc);
298 	struct brcmstb_gpio_bank *bank;
299 
300 	/* Interrupts weren't properly cleared during probe */
301 	BUG_ON(!priv || !chip);
302 
303 	chained_irq_enter(chip, desc);
304 	list_for_each_entry(bank, &priv->bank_list, node)
305 		brcmstb_gpio_irq_bank_handler(bank);
306 	chained_irq_exit(chip, desc);
307 }
308 
309 static struct brcmstb_gpio_bank *brcmstb_gpio_hwirq_to_bank(
310 		struct brcmstb_gpio_priv *priv, irq_hw_number_t hwirq)
311 {
312 	struct brcmstb_gpio_bank *bank;
313 	int i = 0;
314 
315 	/* banks are in descending order */
316 	list_for_each_entry_reverse(bank, &priv->bank_list, node) {
317 		i += bank->gc.ngpio;
318 		if (hwirq < i)
319 			return bank;
320 	}
321 	return NULL;
322 }
323 
324 /*
325  * This lock class tells lockdep that GPIO irqs are in a different
326  * category than their parents, so it won't report false recursion.
327  */
328 static struct lock_class_key brcmstb_gpio_irq_lock_class;
329 static struct lock_class_key brcmstb_gpio_irq_request_class;
330 
331 
332 static int brcmstb_gpio_irq_map(struct irq_domain *d, unsigned int irq,
333 		irq_hw_number_t hwirq)
334 {
335 	struct brcmstb_gpio_priv *priv = d->host_data;
336 	struct brcmstb_gpio_bank *bank =
337 		brcmstb_gpio_hwirq_to_bank(priv, hwirq);
338 	struct platform_device *pdev = priv->pdev;
339 	int ret;
340 
341 	if (!bank)
342 		return -EINVAL;
343 
344 	dev_dbg(&pdev->dev, "Mapping irq %d for gpio line %d (bank %d)\n",
345 		irq, (int)hwirq, bank->id);
346 	ret = irq_set_chip_data(irq, &bank->gc);
347 	if (ret < 0)
348 		return ret;
349 	irq_set_lockdep_class(irq, &brcmstb_gpio_irq_lock_class,
350 			      &brcmstb_gpio_irq_request_class);
351 	irq_set_chip_and_handler(irq, &priv->irq_chip, handle_level_irq);
352 	irq_set_noprobe(irq);
353 	return 0;
354 }
355 
356 static void brcmstb_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
357 {
358 	irq_set_chip_and_handler(irq, NULL, NULL);
359 	irq_set_chip_data(irq, NULL);
360 }
361 
362 static const struct irq_domain_ops brcmstb_gpio_irq_domain_ops = {
363 	.map = brcmstb_gpio_irq_map,
364 	.unmap = brcmstb_gpio_irq_unmap,
365 	.xlate = irq_domain_xlate_twocell,
366 };
367 
368 /* Make sure that the number of banks matches up between properties */
369 static int brcmstb_gpio_sanity_check_banks(struct device *dev,
370 		struct device_node *np, struct resource *res)
371 {
372 	int res_num_banks = resource_size(res) / GIO_BANK_SIZE;
373 	int num_banks =
374 		of_property_count_u32_elems(np, "brcm,gpio-bank-widths");
375 
376 	if (res_num_banks != num_banks) {
377 		dev_err(dev, "Mismatch in banks: res had %d, bank-widths had %d\n",
378 				res_num_banks, num_banks);
379 		return -EINVAL;
380 	} else {
381 		return 0;
382 	}
383 }
384 
385 static int brcmstb_gpio_remove(struct platform_device *pdev)
386 {
387 	struct brcmstb_gpio_priv *priv = platform_get_drvdata(pdev);
388 	struct brcmstb_gpio_bank *bank;
389 	int offset, ret = 0, virq;
390 
391 	if (!priv) {
392 		dev_err(&pdev->dev, "called %s without drvdata!\n", __func__);
393 		return -EFAULT;
394 	}
395 
396 	if (priv->parent_irq > 0)
397 		irq_set_chained_handler_and_data(priv->parent_irq, NULL, NULL);
398 
399 	/* Remove all IRQ mappings and delete the domain */
400 	if (priv->irq_domain) {
401 		for (offset = 0; offset < priv->num_gpios; offset++) {
402 			virq = irq_find_mapping(priv->irq_domain, offset);
403 			irq_dispose_mapping(virq);
404 		}
405 		irq_domain_remove(priv->irq_domain);
406 	}
407 
408 	/*
409 	 * You can lose return values below, but we report all errors, and it's
410 	 * more important to actually perform all of the steps.
411 	 */
412 	list_for_each_entry(bank, &priv->bank_list, node)
413 		gpiochip_remove(&bank->gc);
414 
415 	return ret;
416 }
417 
418 static int brcmstb_gpio_of_xlate(struct gpio_chip *gc,
419 		const struct of_phandle_args *gpiospec, u32 *flags)
420 {
421 	struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
422 	struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
423 	int offset;
424 
425 	if (gc->of_gpio_n_cells != 2) {
426 		WARN_ON(1);
427 		return -EINVAL;
428 	}
429 
430 	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
431 		return -EINVAL;
432 
433 	offset = gpiospec->args[0] - (gc->base - priv->gpio_base);
434 	if (offset >= gc->ngpio || offset < 0)
435 		return -EINVAL;
436 
437 	if (unlikely(offset >= bank->width)) {
438 		dev_warn_ratelimited(&priv->pdev->dev,
439 			"Received request for invalid GPIO offset %d\n",
440 			gpiospec->args[0]);
441 	}
442 
443 	if (flags)
444 		*flags = gpiospec->args[1];
445 
446 	return offset;
447 }
448 
449 /* priv->parent_irq and priv->num_gpios must be set before calling */
450 static int brcmstb_gpio_irq_setup(struct platform_device *pdev,
451 		struct brcmstb_gpio_priv *priv)
452 {
453 	struct device *dev = &pdev->dev;
454 	struct device_node *np = dev->of_node;
455 	int err;
456 
457 	priv->irq_domain =
458 		irq_domain_add_linear(np, priv->num_gpios,
459 				      &brcmstb_gpio_irq_domain_ops,
460 				      priv);
461 	if (!priv->irq_domain) {
462 		dev_err(dev, "Couldn't allocate IRQ domain\n");
463 		return -ENXIO;
464 	}
465 
466 	if (of_property_read_bool(np, "wakeup-source")) {
467 		priv->parent_wake_irq = platform_get_irq(pdev, 1);
468 		if (priv->parent_wake_irq < 0) {
469 			priv->parent_wake_irq = 0;
470 			dev_warn(dev,
471 				"Couldn't get wake IRQ - GPIOs will not be able to wake from sleep");
472 		} else {
473 			/*
474 			 * Set wakeup capability so we can process boot-time
475 			 * "wakeups" (e.g., from S5 cold boot)
476 			 */
477 			device_set_wakeup_capable(dev, true);
478 			device_wakeup_enable(dev);
479 			err = devm_request_irq(dev, priv->parent_wake_irq,
480 					       brcmstb_gpio_wake_irq_handler,
481 					       IRQF_SHARED,
482 					       "brcmstb-gpio-wake", priv);
483 
484 			if (err < 0) {
485 				dev_err(dev, "Couldn't request wake IRQ");
486 				goto out_free_domain;
487 			}
488 		}
489 	}
490 
491 	priv->irq_chip.name = dev_name(dev);
492 	priv->irq_chip.irq_disable = brcmstb_gpio_irq_mask;
493 	priv->irq_chip.irq_mask = brcmstb_gpio_irq_mask;
494 	priv->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask;
495 	priv->irq_chip.irq_ack = brcmstb_gpio_irq_ack;
496 	priv->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type;
497 
498 	if (priv->parent_wake_irq)
499 		priv->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake;
500 
501 	irq_set_chained_handler_and_data(priv->parent_irq,
502 					 brcmstb_gpio_irq_handler, priv);
503 	irq_set_status_flags(priv->parent_irq, IRQ_DISABLE_UNLAZY);
504 
505 	return 0;
506 
507 out_free_domain:
508 	irq_domain_remove(priv->irq_domain);
509 
510 	return err;
511 }
512 
513 static void brcmstb_gpio_bank_save(struct brcmstb_gpio_priv *priv,
514 				   struct brcmstb_gpio_bank *bank)
515 {
516 	struct gpio_chip *gc = &bank->gc;
517 	unsigned int i;
518 
519 	for (i = 0; i < GIO_REG_STAT; i++)
520 		bank->saved_regs[i] = gc->read_reg(priv->reg_base +
521 						   GIO_BANK_OFF(bank->id, i));
522 }
523 
524 static void brcmstb_gpio_quiesce(struct device *dev, bool save)
525 {
526 	struct brcmstb_gpio_priv *priv = dev_get_drvdata(dev);
527 	struct brcmstb_gpio_bank *bank;
528 	struct gpio_chip *gc;
529 	u32 imask;
530 
531 	/* disable non-wake interrupt */
532 	if (priv->parent_irq >= 0)
533 		disable_irq(priv->parent_irq);
534 
535 	list_for_each_entry(bank, &priv->bank_list, node) {
536 		gc = &bank->gc;
537 
538 		if (save)
539 			brcmstb_gpio_bank_save(priv, bank);
540 
541 		/* Unmask GPIOs which have been flagged as wake-up sources */
542 		if (priv->parent_wake_irq)
543 			imask = bank->wake_active;
544 		else
545 			imask = 0;
546 		gc->write_reg(priv->reg_base + GIO_MASK(bank->id),
547 			       imask);
548 	}
549 }
550 
551 static void brcmstb_gpio_shutdown(struct platform_device *pdev)
552 {
553 	/* Enable GPIO for S5 cold boot */
554 	brcmstb_gpio_quiesce(&pdev->dev, false);
555 }
556 
557 #ifdef CONFIG_PM_SLEEP
558 static void brcmstb_gpio_bank_restore(struct brcmstb_gpio_priv *priv,
559 				      struct brcmstb_gpio_bank *bank)
560 {
561 	struct gpio_chip *gc = &bank->gc;
562 	unsigned int i;
563 
564 	for (i = 0; i < GIO_REG_STAT; i++)
565 		gc->write_reg(priv->reg_base + GIO_BANK_OFF(bank->id, i),
566 			      bank->saved_regs[i]);
567 }
568 
569 static int brcmstb_gpio_suspend(struct device *dev)
570 {
571 	brcmstb_gpio_quiesce(dev, true);
572 	return 0;
573 }
574 
575 static int brcmstb_gpio_resume(struct device *dev)
576 {
577 	struct brcmstb_gpio_priv *priv = dev_get_drvdata(dev);
578 	struct brcmstb_gpio_bank *bank;
579 	bool need_wakeup_event = false;
580 
581 	list_for_each_entry(bank, &priv->bank_list, node) {
582 		need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank);
583 		brcmstb_gpio_bank_restore(priv, bank);
584 	}
585 
586 	if (priv->parent_wake_irq && need_wakeup_event)
587 		pm_wakeup_event(dev, 0);
588 
589 	/* enable non-wake interrupt */
590 	if (priv->parent_irq >= 0)
591 		enable_irq(priv->parent_irq);
592 
593 	return 0;
594 }
595 
596 #else
597 #define brcmstb_gpio_suspend	NULL
598 #define brcmstb_gpio_resume	NULL
599 #endif /* CONFIG_PM_SLEEP */
600 
601 static const struct dev_pm_ops brcmstb_gpio_pm_ops = {
602 	.suspend_noirq	= brcmstb_gpio_suspend,
603 	.resume_noirq = brcmstb_gpio_resume,
604 };
605 
606 static int brcmstb_gpio_probe(struct platform_device *pdev)
607 {
608 	struct device *dev = &pdev->dev;
609 	struct device_node *np = dev->of_node;
610 	void __iomem *reg_base;
611 	struct brcmstb_gpio_priv *priv;
612 	struct resource *res;
613 	struct property *prop;
614 	const __be32 *p;
615 	u32 bank_width;
616 	int num_banks = 0;
617 	int err;
618 	static int gpio_base;
619 	unsigned long flags = 0;
620 	bool need_wakeup_event = false;
621 
622 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
623 	if (!priv)
624 		return -ENOMEM;
625 	platform_set_drvdata(pdev, priv);
626 	INIT_LIST_HEAD(&priv->bank_list);
627 
628 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
629 	reg_base = devm_ioremap_resource(dev, res);
630 	if (IS_ERR(reg_base))
631 		return PTR_ERR(reg_base);
632 
633 	priv->gpio_base = gpio_base;
634 	priv->reg_base = reg_base;
635 	priv->pdev = pdev;
636 
637 	if (of_property_read_bool(np, "interrupt-controller")) {
638 		priv->parent_irq = platform_get_irq(pdev, 0);
639 		if (priv->parent_irq <= 0)
640 			return -ENOENT;
641 	} else {
642 		priv->parent_irq = -ENOENT;
643 	}
644 
645 	if (brcmstb_gpio_sanity_check_banks(dev, np, res))
646 		return -EINVAL;
647 
648 	/*
649 	 * MIPS endianness is configured by boot strap, which also reverses all
650 	 * bus endianness (i.e., big-endian CPU + big endian bus ==> native
651 	 * endian I/O).
652 	 *
653 	 * Other architectures (e.g., ARM) either do not support big endian, or
654 	 * else leave I/O in little endian mode.
655 	 */
656 #if defined(CONFIG_MIPS) && defined(__BIG_ENDIAN)
657 	flags = BGPIOF_BIG_ENDIAN_BYTE_ORDER;
658 #endif
659 
660 	of_property_for_each_u32(np, "brcm,gpio-bank-widths", prop, p,
661 			bank_width) {
662 		struct brcmstb_gpio_bank *bank;
663 		struct gpio_chip *gc;
664 
665 		/*
666 		 * If bank_width is 0, then there is an empty bank in the
667 		 * register block. Special handling for this case.
668 		 */
669 		if (bank_width == 0) {
670 			dev_dbg(dev, "Width 0 found: Empty bank @ %d\n",
671 				num_banks);
672 			num_banks++;
673 			gpio_base += MAX_GPIO_PER_BANK;
674 			continue;
675 		}
676 
677 		bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);
678 		if (!bank) {
679 			err = -ENOMEM;
680 			goto fail;
681 		}
682 
683 		bank->parent_priv = priv;
684 		bank->id = num_banks;
685 		if (bank_width <= 0 || bank_width > MAX_GPIO_PER_BANK) {
686 			dev_err(dev, "Invalid bank width %d\n", bank_width);
687 			err = -EINVAL;
688 			goto fail;
689 		} else {
690 			bank->width = bank_width;
691 		}
692 
693 		/*
694 		 * Regs are 4 bytes wide, have data reg, no set/clear regs,
695 		 * and direction bits have 0 = output and 1 = input
696 		 */
697 		gc = &bank->gc;
698 		err = bgpio_init(gc, dev, 4,
699 				reg_base + GIO_DATA(bank->id),
700 				NULL, NULL, NULL,
701 				reg_base + GIO_IODIR(bank->id), flags);
702 		if (err) {
703 			dev_err(dev, "bgpio_init() failed\n");
704 			goto fail;
705 		}
706 
707 		gc->of_node = np;
708 		gc->owner = THIS_MODULE;
709 		gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", dev->of_node);
710 		if (!gc->label) {
711 			err = -ENOMEM;
712 			goto fail;
713 		}
714 		gc->base = gpio_base;
715 		gc->of_gpio_n_cells = 2;
716 		gc->of_xlate = brcmstb_gpio_of_xlate;
717 		/* not all ngpio lines are valid, will use bank width later */
718 		gc->ngpio = MAX_GPIO_PER_BANK;
719 		if (priv->parent_irq > 0)
720 			gc->to_irq = brcmstb_gpio_to_irq;
721 
722 		/*
723 		 * Mask all interrupts by default, since wakeup interrupts may
724 		 * be retained from S5 cold boot
725 		 */
726 		need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank);
727 		gc->write_reg(reg_base + GIO_MASK(bank->id), 0);
728 
729 		err = gpiochip_add_data(gc, bank);
730 		if (err) {
731 			dev_err(dev, "Could not add gpiochip for bank %d\n",
732 					bank->id);
733 			goto fail;
734 		}
735 		gpio_base += gc->ngpio;
736 
737 		dev_dbg(dev, "bank=%d, base=%d, ngpio=%d, width=%d\n", bank->id,
738 			gc->base, gc->ngpio, bank->width);
739 
740 		/* Everything looks good, so add bank to list */
741 		list_add(&bank->node, &priv->bank_list);
742 
743 		num_banks++;
744 	}
745 
746 	priv->num_gpios = gpio_base - priv->gpio_base;
747 	if (priv->parent_irq > 0) {
748 		err = brcmstb_gpio_irq_setup(pdev, priv);
749 		if (err)
750 			goto fail;
751 	}
752 
753 	if (priv->parent_wake_irq && need_wakeup_event)
754 		pm_wakeup_event(dev, 0);
755 
756 	return 0;
757 
758 fail:
759 	(void) brcmstb_gpio_remove(pdev);
760 	return err;
761 }
762 
763 static const struct of_device_id brcmstb_gpio_of_match[] = {
764 	{ .compatible = "brcm,brcmstb-gpio" },
765 	{},
766 };
767 
768 MODULE_DEVICE_TABLE(of, brcmstb_gpio_of_match);
769 
770 static struct platform_driver brcmstb_gpio_driver = {
771 	.driver = {
772 		.name = "brcmstb-gpio",
773 		.of_match_table = brcmstb_gpio_of_match,
774 		.pm = &brcmstb_gpio_pm_ops,
775 	},
776 	.probe = brcmstb_gpio_probe,
777 	.remove = brcmstb_gpio_remove,
778 	.shutdown = brcmstb_gpio_shutdown,
779 };
780 module_platform_driver(brcmstb_gpio_driver);
781 
782 MODULE_AUTHOR("Gregory Fong");
783 MODULE_DESCRIPTION("Driver for Broadcom BRCMSTB SoC UPG GPIO");
784 MODULE_LICENSE("GPL v2");
785