1 /*
2 * Broadcom Kona GPIO Driver
3 *
4 * Author: Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>
5 * Copyright (C) 2012-2014 Broadcom Corporation
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation version 2.
10 *
11 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12 * kind, whether express or implied; without even the implied warranty
13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 */
16
17 #include <linux/bitops.h>
18 #include <linux/err.h>
19 #include <linux/io.h>
20 #include <linux/gpio/driver.h>
21 #include <linux/of_device.h>
22 #include <linux/of_irq.h>
23 #include <linux/init.h>
24 #include <linux/irqdomain.h>
25 #include <linux/irqchip/chained_irq.h>
26
27 #define BCM_GPIO_PASSWD 0x00a5a501
28 #define GPIO_PER_BANK 32
29 #define GPIO_MAX_BANK_NUM 8
30
31 #define GPIO_BANK(gpio) ((gpio) >> 5)
32 #define GPIO_BIT(gpio) ((gpio) & (GPIO_PER_BANK - 1))
33
34 /* There is a GPIO control register for each GPIO */
35 #define GPIO_CONTROL(gpio) (0x00000100 + ((gpio) << 2))
36
37 /* The remaining registers are per GPIO bank */
38 #define GPIO_OUT_STATUS(bank) (0x00000000 + ((bank) << 2))
39 #define GPIO_IN_STATUS(bank) (0x00000020 + ((bank) << 2))
40 #define GPIO_OUT_SET(bank) (0x00000040 + ((bank) << 2))
41 #define GPIO_OUT_CLEAR(bank) (0x00000060 + ((bank) << 2))
42 #define GPIO_INT_STATUS(bank) (0x00000080 + ((bank) << 2))
43 #define GPIO_INT_MASK(bank) (0x000000a0 + ((bank) << 2))
44 #define GPIO_INT_MSKCLR(bank) (0x000000c0 + ((bank) << 2))
45 #define GPIO_PWD_STATUS(bank) (0x00000500 + ((bank) << 2))
46
47 #define GPIO_GPPWR_OFFSET 0x00000520
48
49 #define GPIO_GPCTR0_DBR_SHIFT 5
50 #define GPIO_GPCTR0_DBR_MASK 0x000001e0
51
52 #define GPIO_GPCTR0_ITR_SHIFT 3
53 #define GPIO_GPCTR0_ITR_MASK 0x00000018
54 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE 0x00000001
55 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE 0x00000002
56 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE 0x00000003
57
58 #define GPIO_GPCTR0_IOTR_MASK 0x00000001
59 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT 0x00000000
60 #define GPIO_GPCTR0_IOTR_CMD_INPUT 0x00000001
61
62 #define GPIO_GPCTR0_DB_ENABLE_MASK 0x00000100
63
64 #define LOCK_CODE 0xffffffff
65 #define UNLOCK_CODE 0x00000000
66
67 struct bcm_kona_gpio {
68 void __iomem *reg_base;
69 int num_bank;
70 raw_spinlock_t lock;
71 struct gpio_chip gpio_chip;
72 struct irq_domain *irq_domain;
73 struct bcm_kona_gpio_bank *banks;
74 struct platform_device *pdev;
75 };
76
77 struct bcm_kona_gpio_bank {
78 int id;
79 int irq;
80 /* Used in the interrupt handler */
81 struct bcm_kona_gpio *kona_gpio;
82 };
83
bcm_kona_gpio_write_lock_regs(void __iomem * reg_base,int bank_id,u32 lockcode)84 static inline void bcm_kona_gpio_write_lock_regs(void __iomem *reg_base,
85 int bank_id, u32 lockcode)
86 {
87 writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET);
88 writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id));
89 }
90
bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio * kona_gpio,unsigned gpio)91 static void bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio *kona_gpio,
92 unsigned gpio)
93 {
94 u32 val;
95 unsigned long flags;
96 int bank_id = GPIO_BANK(gpio);
97
98 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
99
100 val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
101 val |= BIT(gpio);
102 bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
103
104 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
105 }
106
bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio * kona_gpio,unsigned gpio)107 static void bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio *kona_gpio,
108 unsigned gpio)
109 {
110 u32 val;
111 unsigned long flags;
112 int bank_id = GPIO_BANK(gpio);
113
114 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
115
116 val = readl(kona_gpio->reg_base + GPIO_PWD_STATUS(bank_id));
117 val &= ~BIT(gpio);
118 bcm_kona_gpio_write_lock_regs(kona_gpio->reg_base, bank_id, val);
119
120 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
121 }
122
bcm_kona_gpio_get_dir(struct gpio_chip * chip,unsigned gpio)123 static int bcm_kona_gpio_get_dir(struct gpio_chip *chip, unsigned gpio)
124 {
125 struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
126 void __iomem *reg_base = kona_gpio->reg_base;
127 u32 val;
128
129 val = readl(reg_base + GPIO_CONTROL(gpio)) & GPIO_GPCTR0_IOTR_MASK;
130 return !!val;
131 }
132
bcm_kona_gpio_set(struct gpio_chip * chip,unsigned gpio,int value)133 static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
134 {
135 struct bcm_kona_gpio *kona_gpio;
136 void __iomem *reg_base;
137 int bank_id = GPIO_BANK(gpio);
138 int bit = GPIO_BIT(gpio);
139 u32 val, reg_offset;
140 unsigned long flags;
141
142 kona_gpio = gpiochip_get_data(chip);
143 reg_base = kona_gpio->reg_base;
144 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
145
146 /* this function only applies to output pin */
147 if (bcm_kona_gpio_get_dir(chip, gpio) == 1)
148 goto out;
149
150 reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
151
152 val = readl(reg_base + reg_offset);
153 val |= BIT(bit);
154 writel(val, reg_base + reg_offset);
155
156 out:
157 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
158 }
159
bcm_kona_gpio_get(struct gpio_chip * chip,unsigned gpio)160 static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio)
161 {
162 struct bcm_kona_gpio *kona_gpio;
163 void __iomem *reg_base;
164 int bank_id = GPIO_BANK(gpio);
165 int bit = GPIO_BIT(gpio);
166 u32 val, reg_offset;
167 unsigned long flags;
168
169 kona_gpio = gpiochip_get_data(chip);
170 reg_base = kona_gpio->reg_base;
171 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
172
173 if (bcm_kona_gpio_get_dir(chip, gpio) == 1)
174 reg_offset = GPIO_IN_STATUS(bank_id);
175 else
176 reg_offset = GPIO_OUT_STATUS(bank_id);
177
178 /* read the GPIO bank status */
179 val = readl(reg_base + reg_offset);
180
181 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
182
183 /* return the specified bit status */
184 return !!(val & BIT(bit));
185 }
186
bcm_kona_gpio_request(struct gpio_chip * chip,unsigned gpio)187 static int bcm_kona_gpio_request(struct gpio_chip *chip, unsigned gpio)
188 {
189 struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
190
191 bcm_kona_gpio_unlock_gpio(kona_gpio, gpio);
192 return 0;
193 }
194
bcm_kona_gpio_free(struct gpio_chip * chip,unsigned gpio)195 static void bcm_kona_gpio_free(struct gpio_chip *chip, unsigned gpio)
196 {
197 struct bcm_kona_gpio *kona_gpio = gpiochip_get_data(chip);
198
199 bcm_kona_gpio_lock_gpio(kona_gpio, gpio);
200 }
201
bcm_kona_gpio_direction_input(struct gpio_chip * chip,unsigned gpio)202 static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
203 {
204 struct bcm_kona_gpio *kona_gpio;
205 void __iomem *reg_base;
206 u32 val;
207 unsigned long flags;
208
209 kona_gpio = gpiochip_get_data(chip);
210 reg_base = kona_gpio->reg_base;
211 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
212
213 val = readl(reg_base + GPIO_CONTROL(gpio));
214 val &= ~GPIO_GPCTR0_IOTR_MASK;
215 val |= GPIO_GPCTR0_IOTR_CMD_INPUT;
216 writel(val, reg_base + GPIO_CONTROL(gpio));
217
218 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
219
220 return 0;
221 }
222
bcm_kona_gpio_direction_output(struct gpio_chip * chip,unsigned gpio,int value)223 static int bcm_kona_gpio_direction_output(struct gpio_chip *chip,
224 unsigned gpio, int value)
225 {
226 struct bcm_kona_gpio *kona_gpio;
227 void __iomem *reg_base;
228 int bank_id = GPIO_BANK(gpio);
229 int bit = GPIO_BIT(gpio);
230 u32 val, reg_offset;
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_0UTPUT;
240 writel(val, reg_base + GPIO_CONTROL(gpio));
241 reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id);
242
243 val = readl(reg_base + reg_offset);
244 val |= BIT(bit);
245 writel(val, reg_base + reg_offset);
246
247 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
248
249 return 0;
250 }
251
bcm_kona_gpio_to_irq(struct gpio_chip * chip,unsigned gpio)252 static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
253 {
254 struct bcm_kona_gpio *kona_gpio;
255
256 kona_gpio = gpiochip_get_data(chip);
257 if (gpio >= kona_gpio->gpio_chip.ngpio)
258 return -ENXIO;
259 return irq_create_mapping(kona_gpio->irq_domain, gpio);
260 }
261
bcm_kona_gpio_set_debounce(struct gpio_chip * chip,unsigned gpio,unsigned debounce)262 static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio,
263 unsigned debounce)
264 {
265 struct bcm_kona_gpio *kona_gpio;
266 void __iomem *reg_base;
267 u32 val, res;
268 unsigned long flags;
269
270 kona_gpio = gpiochip_get_data(chip);
271 reg_base = kona_gpio->reg_base;
272 /* debounce must be 1-128ms (or 0) */
273 if ((debounce > 0 && debounce < 1000) || debounce > 128000) {
274 dev_err(chip->parent, "Debounce value %u not in range\n",
275 debounce);
276 return -EINVAL;
277 }
278
279 /* calculate debounce bit value */
280 if (debounce != 0) {
281 /* Convert to ms */
282 debounce /= 1000;
283 /* find the MSB */
284 res = fls(debounce) - 1;
285 /* Check if MSB-1 is set (round up or down) */
286 if (res > 0 && (debounce & BIT(res - 1)))
287 res++;
288 }
289
290 /* spin lock for read-modify-write of the GPIO register */
291 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
292
293 val = readl(reg_base + GPIO_CONTROL(gpio));
294 val &= ~GPIO_GPCTR0_DBR_MASK;
295
296 if (debounce == 0) {
297 /* disable debounce */
298 val &= ~GPIO_GPCTR0_DB_ENABLE_MASK;
299 } else {
300 val |= GPIO_GPCTR0_DB_ENABLE_MASK |
301 (res << GPIO_GPCTR0_DBR_SHIFT);
302 }
303
304 writel(val, reg_base + GPIO_CONTROL(gpio));
305
306 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
307
308 return 0;
309 }
310
bcm_kona_gpio_set_config(struct gpio_chip * chip,unsigned gpio,unsigned long config)311 static int bcm_kona_gpio_set_config(struct gpio_chip *chip, unsigned gpio,
312 unsigned long config)
313 {
314 u32 debounce;
315
316 if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
317 return -ENOTSUPP;
318
319 debounce = pinconf_to_config_argument(config);
320 return bcm_kona_gpio_set_debounce(chip, gpio, debounce);
321 }
322
323 static const struct gpio_chip template_chip = {
324 .label = "bcm-kona-gpio",
325 .owner = THIS_MODULE,
326 .request = bcm_kona_gpio_request,
327 .free = bcm_kona_gpio_free,
328 .get_direction = bcm_kona_gpio_get_dir,
329 .direction_input = bcm_kona_gpio_direction_input,
330 .get = bcm_kona_gpio_get,
331 .direction_output = bcm_kona_gpio_direction_output,
332 .set = bcm_kona_gpio_set,
333 .set_config = bcm_kona_gpio_set_config,
334 .to_irq = bcm_kona_gpio_to_irq,
335 .base = 0,
336 };
337
bcm_kona_gpio_irq_ack(struct irq_data * d)338 static void bcm_kona_gpio_irq_ack(struct irq_data *d)
339 {
340 struct bcm_kona_gpio *kona_gpio;
341 void __iomem *reg_base;
342 unsigned gpio = d->hwirq;
343 int bank_id = GPIO_BANK(gpio);
344 int bit = GPIO_BIT(gpio);
345 u32 val;
346 unsigned long flags;
347
348 kona_gpio = irq_data_get_irq_chip_data(d);
349 reg_base = kona_gpio->reg_base;
350 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
351
352 val = readl(reg_base + GPIO_INT_STATUS(bank_id));
353 val |= BIT(bit);
354 writel(val, reg_base + GPIO_INT_STATUS(bank_id));
355
356 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
357 }
358
bcm_kona_gpio_irq_mask(struct irq_data * d)359 static void bcm_kona_gpio_irq_mask(struct irq_data *d)
360 {
361 struct bcm_kona_gpio *kona_gpio;
362 void __iomem *reg_base;
363 unsigned gpio = d->hwirq;
364 int bank_id = GPIO_BANK(gpio);
365 int bit = GPIO_BIT(gpio);
366 u32 val;
367 unsigned long flags;
368
369 kona_gpio = irq_data_get_irq_chip_data(d);
370 reg_base = kona_gpio->reg_base;
371 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
372
373 val = readl(reg_base + GPIO_INT_MASK(bank_id));
374 val |= BIT(bit);
375 writel(val, reg_base + GPIO_INT_MASK(bank_id));
376
377 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
378 }
379
bcm_kona_gpio_irq_unmask(struct irq_data * d)380 static void bcm_kona_gpio_irq_unmask(struct irq_data *d)
381 {
382 struct bcm_kona_gpio *kona_gpio;
383 void __iomem *reg_base;
384 unsigned gpio = d->hwirq;
385 int bank_id = GPIO_BANK(gpio);
386 int bit = GPIO_BIT(gpio);
387 u32 val;
388 unsigned long flags;
389
390 kona_gpio = irq_data_get_irq_chip_data(d);
391 reg_base = kona_gpio->reg_base;
392 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
393
394 val = readl(reg_base + GPIO_INT_MSKCLR(bank_id));
395 val |= BIT(bit);
396 writel(val, reg_base + GPIO_INT_MSKCLR(bank_id));
397
398 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
399 }
400
bcm_kona_gpio_irq_set_type(struct irq_data * d,unsigned int type)401 static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type)
402 {
403 struct bcm_kona_gpio *kona_gpio;
404 void __iomem *reg_base;
405 unsigned gpio = d->hwirq;
406 u32 lvl_type;
407 u32 val;
408 unsigned long flags;
409
410 kona_gpio = irq_data_get_irq_chip_data(d);
411 reg_base = kona_gpio->reg_base;
412 switch (type & IRQ_TYPE_SENSE_MASK) {
413 case IRQ_TYPE_EDGE_RISING:
414 lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE;
415 break;
416
417 case IRQ_TYPE_EDGE_FALLING:
418 lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE;
419 break;
420
421 case IRQ_TYPE_EDGE_BOTH:
422 lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE;
423 break;
424
425 case IRQ_TYPE_LEVEL_HIGH:
426 case IRQ_TYPE_LEVEL_LOW:
427 /* BCM GPIO doesn't support level triggering */
428 default:
429 dev_err(kona_gpio->gpio_chip.parent,
430 "Invalid BCM GPIO irq type 0x%x\n", type);
431 return -EINVAL;
432 }
433
434 raw_spin_lock_irqsave(&kona_gpio->lock, flags);
435
436 val = readl(reg_base + GPIO_CONTROL(gpio));
437 val &= ~GPIO_GPCTR0_ITR_MASK;
438 val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT;
439 writel(val, reg_base + GPIO_CONTROL(gpio));
440
441 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
442
443 return 0;
444 }
445
bcm_kona_gpio_irq_handler(struct irq_desc * desc)446 static void bcm_kona_gpio_irq_handler(struct irq_desc *desc)
447 {
448 void __iomem *reg_base;
449 int bit, bank_id;
450 unsigned long sta;
451 struct bcm_kona_gpio_bank *bank = irq_desc_get_handler_data(desc);
452 struct irq_chip *chip = irq_desc_get_chip(desc);
453
454 chained_irq_enter(chip, desc);
455
456 /*
457 * For bank interrupts, we can't use chip_data to store the kona_gpio
458 * pointer, since GIC needs it for its own purposes. Therefore, we get
459 * our pointer from the bank structure.
460 */
461 reg_base = bank->kona_gpio->reg_base;
462 bank_id = bank->id;
463
464 while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) &
465 (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) {
466 for_each_set_bit(bit, &sta, 32) {
467 int hwirq = GPIO_PER_BANK * bank_id + bit;
468 int child_irq =
469 irq_find_mapping(bank->kona_gpio->irq_domain,
470 hwirq);
471 /*
472 * Clear interrupt before handler is called so we don't
473 * miss any interrupt occurred during executing them.
474 */
475 writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) |
476 BIT(bit), reg_base + GPIO_INT_STATUS(bank_id));
477 /* Invoke interrupt handler */
478 generic_handle_irq(child_irq);
479 }
480 }
481
482 chained_irq_exit(chip, desc);
483 }
484
bcm_kona_gpio_irq_reqres(struct irq_data * d)485 static int bcm_kona_gpio_irq_reqres(struct irq_data *d)
486 {
487 struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
488 int ret;
489
490 ret = gpiochip_lock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
491 if (ret) {
492 dev_err(kona_gpio->gpio_chip.parent,
493 "unable to lock HW IRQ %lu for IRQ\n",
494 d->hwirq);
495 return ret;
496 }
497 return 0;
498 }
499
bcm_kona_gpio_irq_relres(struct irq_data * d)500 static void bcm_kona_gpio_irq_relres(struct irq_data *d)
501 {
502 struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d);
503
504 gpiochip_unlock_as_irq(&kona_gpio->gpio_chip, d->hwirq);
505 }
506
507 static struct irq_chip bcm_gpio_irq_chip = {
508 .name = "bcm-kona-gpio",
509 .irq_ack = bcm_kona_gpio_irq_ack,
510 .irq_mask = bcm_kona_gpio_irq_mask,
511 .irq_unmask = bcm_kona_gpio_irq_unmask,
512 .irq_set_type = bcm_kona_gpio_irq_set_type,
513 .irq_request_resources = bcm_kona_gpio_irq_reqres,
514 .irq_release_resources = bcm_kona_gpio_irq_relres,
515 };
516
517 static struct of_device_id const bcm_kona_gpio_of_match[] = {
518 { .compatible = "brcm,kona-gpio" },
519 {}
520 };
521
522 /*
523 * This lock class tells lockdep that GPIO irqs are in a different
524 * category than their parents, so it won't report false recursion.
525 */
526 static struct lock_class_key gpio_lock_class;
527 static struct lock_class_key gpio_request_class;
528
bcm_kona_gpio_irq_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hwirq)529 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
530 irq_hw_number_t hwirq)
531 {
532 int ret;
533
534 ret = irq_set_chip_data(irq, d->host_data);
535 if (ret < 0)
536 return ret;
537 irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
538 irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
539 irq_set_noprobe(irq);
540
541 return 0;
542 }
543
bcm_kona_gpio_irq_unmap(struct irq_domain * d,unsigned int irq)544 static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
545 {
546 irq_set_chip_and_handler(irq, NULL, NULL);
547 irq_set_chip_data(irq, NULL);
548 }
549
550 static const struct irq_domain_ops bcm_kona_irq_ops = {
551 .map = bcm_kona_gpio_irq_map,
552 .unmap = bcm_kona_gpio_irq_unmap,
553 .xlate = irq_domain_xlate_twocell,
554 };
555
bcm_kona_gpio_reset(struct bcm_kona_gpio * kona_gpio)556 static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio)
557 {
558 void __iomem *reg_base;
559 int i;
560
561 reg_base = kona_gpio->reg_base;
562 /* disable interrupts and clear status */
563 for (i = 0; i < kona_gpio->num_bank; i++) {
564 /* Unlock the entire bank first */
565 bcm_kona_gpio_write_lock_regs(reg_base, i, UNLOCK_CODE);
566 writel(0xffffffff, reg_base + GPIO_INT_MASK(i));
567 writel(0xffffffff, reg_base + GPIO_INT_STATUS(i));
568 /* Now re-lock the bank */
569 bcm_kona_gpio_write_lock_regs(reg_base, i, LOCK_CODE);
570 }
571 }
572
bcm_kona_gpio_probe(struct platform_device * pdev)573 static int bcm_kona_gpio_probe(struct platform_device *pdev)
574 {
575 struct device *dev = &pdev->dev;
576 const struct of_device_id *match;
577 struct resource *res;
578 struct bcm_kona_gpio_bank *bank;
579 struct bcm_kona_gpio *kona_gpio;
580 struct gpio_chip *chip;
581 int ret;
582 int i;
583
584 match = of_match_device(bcm_kona_gpio_of_match, dev);
585 if (!match) {
586 dev_err(dev, "Failed to find gpio controller\n");
587 return -ENODEV;
588 }
589
590 kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL);
591 if (!kona_gpio)
592 return -ENOMEM;
593
594 kona_gpio->gpio_chip = template_chip;
595 chip = &kona_gpio->gpio_chip;
596 kona_gpio->num_bank = of_irq_count(dev->of_node);
597 if (kona_gpio->num_bank == 0) {
598 dev_err(dev, "Couldn't determine # GPIO banks\n");
599 return -ENOENT;
600 }
601 if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) {
602 dev_err(dev, "Too many GPIO banks configured (max=%d)\n",
603 GPIO_MAX_BANK_NUM);
604 return -ENXIO;
605 }
606 kona_gpio->banks = devm_kcalloc(dev,
607 kona_gpio->num_bank,
608 sizeof(*kona_gpio->banks),
609 GFP_KERNEL);
610 if (!kona_gpio->banks)
611 return -ENOMEM;
612
613 kona_gpio->pdev = pdev;
614 platform_set_drvdata(pdev, kona_gpio);
615 chip->of_node = dev->of_node;
616 chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK;
617
618 kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node,
619 chip->ngpio,
620 &bcm_kona_irq_ops,
621 kona_gpio);
622 if (!kona_gpio->irq_domain) {
623 dev_err(dev, "Couldn't allocate IRQ domain\n");
624 return -ENXIO;
625 }
626
627 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
628 kona_gpio->reg_base = devm_ioremap_resource(dev, res);
629 if (IS_ERR(kona_gpio->reg_base)) {
630 ret = -ENXIO;
631 goto err_irq_domain;
632 }
633
634 for (i = 0; i < kona_gpio->num_bank; i++) {
635 bank = &kona_gpio->banks[i];
636 bank->id = i;
637 bank->irq = platform_get_irq(pdev, i);
638 bank->kona_gpio = kona_gpio;
639 if (bank->irq < 0) {
640 dev_err(dev, "Couldn't get IRQ for bank %d", i);
641 ret = -ENOENT;
642 goto err_irq_domain;
643 }
644 }
645
646 dev_info(&pdev->dev, "Setting up Kona GPIO\n");
647
648 bcm_kona_gpio_reset(kona_gpio);
649
650 ret = devm_gpiochip_add_data(dev, chip, kona_gpio);
651 if (ret < 0) {
652 dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret);
653 goto err_irq_domain;
654 }
655 for (i = 0; i < kona_gpio->num_bank; i++) {
656 bank = &kona_gpio->banks[i];
657 irq_set_chained_handler_and_data(bank->irq,
658 bcm_kona_gpio_irq_handler,
659 bank);
660 }
661
662 raw_spin_lock_init(&kona_gpio->lock);
663
664 return 0;
665
666 err_irq_domain:
667 irq_domain_remove(kona_gpio->irq_domain);
668
669 return ret;
670 }
671
672 static struct platform_driver bcm_kona_gpio_driver = {
673 .driver = {
674 .name = "bcm-kona-gpio",
675 .of_match_table = bcm_kona_gpio_of_match,
676 },
677 .probe = bcm_kona_gpio_probe,
678 };
679 builtin_platform_driver(bcm_kona_gpio_driver);
680