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

source code of linux/drivers/gpio/gpio-brcmstb.c