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
60 struct 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
69 struct 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
bcm_kona_gpio_write_lock_regs(void __iomem * reg_base,int bank_id,u32 lockcode)92 static 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
bcm_kona_gpio_lock_gpio(struct bcm_kona_gpio * kona_gpio,unsigned gpio)99 static 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
bcm_kona_gpio_unlock_gpio(struct bcm_kona_gpio * kona_gpio,unsigned gpio)125 static 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
bcm_kona_gpio_get_dir(struct gpio_chip * chip,unsigned gpio)147 static 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
bcm_kona_gpio_set(struct gpio_chip * chip,unsigned gpio,int value)157 static 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
180 out:
181 raw_spin_unlock_irqrestore(&kona_gpio->lock, flags);
182 }
183
bcm_kona_gpio_get(struct gpio_chip * chip,unsigned gpio)184 static 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
bcm_kona_gpio_request(struct gpio_chip * chip,unsigned gpio)211 static 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
bcm_kona_gpio_free(struct gpio_chip * chip,unsigned gpio)219 static 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
bcm_kona_gpio_direction_input(struct gpio_chip * chip,unsigned gpio)226 static 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
bcm_kona_gpio_direction_output(struct gpio_chip * chip,unsigned gpio,int value)247 static 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
bcm_kona_gpio_to_irq(struct gpio_chip * chip,unsigned gpio)276 static 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
bcm_kona_gpio_set_debounce(struct gpio_chip * chip,unsigned gpio,unsigned debounce)286 static 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
bcm_kona_gpio_set_config(struct gpio_chip * chip,unsigned gpio,unsigned long config)335 static 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
347 static 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
bcm_kona_gpio_irq_ack(struct irq_data * d)362 static 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
bcm_kona_gpio_irq_mask(struct irq_data * d)383 static 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
bcm_kona_gpio_irq_unmask(struct irq_data * d)406 static 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
bcm_kona_gpio_irq_set_type(struct irq_data * d,unsigned int type)429 static 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
bcm_kona_gpio_irq_handler(struct irq_desc * desc)474 static 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
bcm_kona_gpio_irq_reqres(struct irq_data * d)511 static 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
bcm_kona_gpio_irq_relres(struct irq_data * d)525 static 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
536 static 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
546 static 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 */
555 static struct lock_class_key gpio_lock_class;
556 static struct lock_class_key gpio_request_class;
557
bcm_kona_gpio_irq_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hwirq)558 static 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
bcm_kona_gpio_irq_unmap(struct irq_domain * d,unsigned int irq)573 static 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
579 static 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
bcm_kona_gpio_reset(struct bcm_kona_gpio * kona_gpio)585 static 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
bcm_kona_gpio_probe(struct platform_device * pdev)602 static 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
688 err_irq_domain:
689 irq_domain_remove(kona_gpio->irq_domain);
690
691 return ret;
692 }
693
694 static 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 };
701 builtin_platform_driver(bcm_kona_gpio_driver);
702