xref: /openbmc/linux/drivers/gpio/gpio-rockchip.c (revision 465191d6)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2013 MundoReader S.L.
4  * Author: Heiko Stuebner <heiko@sntech.de>
5  *
6  * Copyright (c) 2021 Rockchip Electronics Co. Ltd.
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/clk.h>
11 #include <linux/device.h>
12 #include <linux/err.h>
13 #include <linux/gpio/driver.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_address.h>
20 #include <linux/of_device.h>
21 #include <linux/of_irq.h>
22 #include <linux/pinctrl/pinconf-generic.h>
23 #include <linux/regmap.h>
24 
25 #include "../pinctrl/core.h"
26 #include "../pinctrl/pinctrl-rockchip.h"
27 
28 #define GPIO_TYPE_V1		(0)           /* GPIO Version ID reserved */
29 #define GPIO_TYPE_V2		(0x01000C2B)  /* GPIO Version ID 0x01000C2B */
30 
31 static const struct rockchip_gpio_regs gpio_regs_v1 = {
32 	.port_dr = 0x00,
33 	.port_ddr = 0x04,
34 	.int_en = 0x30,
35 	.int_mask = 0x34,
36 	.int_type = 0x38,
37 	.int_polarity = 0x3c,
38 	.int_status = 0x40,
39 	.int_rawstatus = 0x44,
40 	.debounce = 0x48,
41 	.port_eoi = 0x4c,
42 	.ext_port = 0x50,
43 };
44 
45 static const struct rockchip_gpio_regs gpio_regs_v2 = {
46 	.port_dr = 0x00,
47 	.port_ddr = 0x08,
48 	.int_en = 0x10,
49 	.int_mask = 0x18,
50 	.int_type = 0x20,
51 	.int_polarity = 0x28,
52 	.int_bothedge = 0x30,
53 	.int_status = 0x50,
54 	.int_rawstatus = 0x58,
55 	.debounce = 0x38,
56 	.dbclk_div_en = 0x40,
57 	.dbclk_div_con = 0x48,
58 	.port_eoi = 0x60,
59 	.ext_port = 0x70,
60 	.version_id = 0x78,
61 };
62 
63 static inline void gpio_writel_v2(u32 val, void __iomem *reg)
64 {
65 	writel((val & 0xffff) | 0xffff0000, reg);
66 	writel((val >> 16) | 0xffff0000, reg + 0x4);
67 }
68 
69 static inline u32 gpio_readl_v2(void __iomem *reg)
70 {
71 	return readl(reg + 0x4) << 16 | readl(reg);
72 }
73 
74 static inline void rockchip_gpio_writel(struct rockchip_pin_bank *bank,
75 					u32 value, unsigned int offset)
76 {
77 	void __iomem *reg = bank->reg_base + offset;
78 
79 	if (bank->gpio_type == GPIO_TYPE_V2)
80 		gpio_writel_v2(value, reg);
81 	else
82 		writel(value, reg);
83 }
84 
85 static inline u32 rockchip_gpio_readl(struct rockchip_pin_bank *bank,
86 				      unsigned int offset)
87 {
88 	void __iomem *reg = bank->reg_base + offset;
89 	u32 value;
90 
91 	if (bank->gpio_type == GPIO_TYPE_V2)
92 		value = gpio_readl_v2(reg);
93 	else
94 		value = readl(reg);
95 
96 	return value;
97 }
98 
99 static inline void rockchip_gpio_writel_bit(struct rockchip_pin_bank *bank,
100 					    u32 bit, u32 value,
101 					    unsigned int offset)
102 {
103 	void __iomem *reg = bank->reg_base + offset;
104 	u32 data;
105 
106 	if (bank->gpio_type == GPIO_TYPE_V2) {
107 		if (value)
108 			data = BIT(bit % 16) | BIT(bit % 16 + 16);
109 		else
110 			data = BIT(bit % 16 + 16);
111 		writel(data, bit >= 16 ? reg + 0x4 : reg);
112 	} else {
113 		data = readl(reg);
114 		data &= ~BIT(bit);
115 		if (value)
116 			data |= BIT(bit);
117 		writel(data, reg);
118 	}
119 }
120 
121 static inline u32 rockchip_gpio_readl_bit(struct rockchip_pin_bank *bank,
122 					  u32 bit, unsigned int offset)
123 {
124 	void __iomem *reg = bank->reg_base + offset;
125 	u32 data;
126 
127 	if (bank->gpio_type == GPIO_TYPE_V2) {
128 		data = readl(bit >= 16 ? reg + 0x4 : reg);
129 		data >>= bit % 16;
130 	} else {
131 		data = readl(reg);
132 		data >>= bit;
133 	}
134 
135 	return data & (0x1);
136 }
137 
138 static int rockchip_gpio_get_direction(struct gpio_chip *chip,
139 				       unsigned int offset)
140 {
141 	struct rockchip_pin_bank *bank = gpiochip_get_data(chip);
142 	u32 data;
143 
144 	data = rockchip_gpio_readl_bit(bank, offset, bank->gpio_regs->port_ddr);
145 	if (data)
146 		return GPIO_LINE_DIRECTION_OUT;
147 
148 	return GPIO_LINE_DIRECTION_IN;
149 }
150 
151 static int rockchip_gpio_set_direction(struct gpio_chip *chip,
152 				       unsigned int offset, bool input)
153 {
154 	struct rockchip_pin_bank *bank = gpiochip_get_data(chip);
155 	unsigned long flags;
156 	u32 data = input ? 0 : 1;
157 
158 	raw_spin_lock_irqsave(&bank->slock, flags);
159 	rockchip_gpio_writel_bit(bank, offset, data, bank->gpio_regs->port_ddr);
160 	raw_spin_unlock_irqrestore(&bank->slock, flags);
161 
162 	return 0;
163 }
164 
165 static void rockchip_gpio_set(struct gpio_chip *gc, unsigned int offset,
166 			      int value)
167 {
168 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
169 	unsigned long flags;
170 
171 	raw_spin_lock_irqsave(&bank->slock, flags);
172 	rockchip_gpio_writel_bit(bank, offset, value, bank->gpio_regs->port_dr);
173 	raw_spin_unlock_irqrestore(&bank->slock, flags);
174 }
175 
176 static int rockchip_gpio_get(struct gpio_chip *gc, unsigned int offset)
177 {
178 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
179 	u32 data;
180 
181 	data = readl(bank->reg_base + bank->gpio_regs->ext_port);
182 	data >>= offset;
183 	data &= 1;
184 
185 	return data;
186 }
187 
188 static int rockchip_gpio_set_debounce(struct gpio_chip *gc,
189 				      unsigned int offset,
190 				      unsigned int debounce)
191 {
192 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
193 	const struct rockchip_gpio_regs	*reg = bank->gpio_regs;
194 	unsigned long flags, div_reg, freq, max_debounce;
195 	bool div_debounce_support;
196 	unsigned int cur_div_reg;
197 	u64 div;
198 
199 	if (bank->gpio_type == GPIO_TYPE_V2 && !IS_ERR(bank->db_clk)) {
200 		div_debounce_support = true;
201 		freq = clk_get_rate(bank->db_clk);
202 		max_debounce = (GENMASK(23, 0) + 1) * 2 * 1000000 / freq;
203 		if (debounce > max_debounce)
204 			return -EINVAL;
205 
206 		div = debounce * freq;
207 		div_reg = DIV_ROUND_CLOSEST_ULL(div, 2 * USEC_PER_SEC) - 1;
208 	} else {
209 		div_debounce_support = false;
210 	}
211 
212 	raw_spin_lock_irqsave(&bank->slock, flags);
213 
214 	/* Only the v1 needs to configure div_en and div_con for dbclk */
215 	if (debounce) {
216 		if (div_debounce_support) {
217 			/* Configure the max debounce from consumers */
218 			cur_div_reg = readl(bank->reg_base +
219 					    reg->dbclk_div_con);
220 			if (cur_div_reg < div_reg)
221 				writel(div_reg, bank->reg_base +
222 				       reg->dbclk_div_con);
223 			rockchip_gpio_writel_bit(bank, offset, 1,
224 						 reg->dbclk_div_en);
225 		}
226 
227 		rockchip_gpio_writel_bit(bank, offset, 1, reg->debounce);
228 	} else {
229 		if (div_debounce_support)
230 			rockchip_gpio_writel_bit(bank, offset, 0,
231 						 reg->dbclk_div_en);
232 
233 		rockchip_gpio_writel_bit(bank, offset, 0, reg->debounce);
234 	}
235 
236 	raw_spin_unlock_irqrestore(&bank->slock, flags);
237 
238 	/* Enable or disable dbclk at last */
239 	if (div_debounce_support) {
240 		if (debounce)
241 			clk_prepare_enable(bank->db_clk);
242 		else
243 			clk_disable_unprepare(bank->db_clk);
244 	}
245 
246 	return 0;
247 }
248 
249 static int rockchip_gpio_direction_input(struct gpio_chip *gc,
250 					 unsigned int offset)
251 {
252 	return rockchip_gpio_set_direction(gc, offset, true);
253 }
254 
255 static int rockchip_gpio_direction_output(struct gpio_chip *gc,
256 					  unsigned int offset, int value)
257 {
258 	rockchip_gpio_set(gc, offset, value);
259 
260 	return rockchip_gpio_set_direction(gc, offset, false);
261 }
262 
263 /*
264  * gpiolib set_config callback function. The setting of the pin
265  * mux function as 'gpio output' will be handled by the pinctrl subsystem
266  * interface.
267  */
268 static int rockchip_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
269 				  unsigned long config)
270 {
271 	enum pin_config_param param = pinconf_to_config_param(config);
272 
273 	switch (param) {
274 	case PIN_CONFIG_INPUT_DEBOUNCE:
275 		rockchip_gpio_set_debounce(gc, offset, true);
276 		/*
277 		 * Rockchip's gpio could only support up to one period
278 		 * of the debounce clock(pclk), which is far away from
279 		 * satisftying the requirement, as pclk is usually near
280 		 * 100MHz shared by all peripherals. So the fact is it
281 		 * has crippled debounce capability could only be useful
282 		 * to prevent any spurious glitches from waking up the system
283 		 * if the gpio is conguired as wakeup interrupt source. Let's
284 		 * still return -ENOTSUPP as before, to make sure the caller
285 		 * of gpiod_set_debounce won't change its behaviour.
286 		 */
287 		return -ENOTSUPP;
288 	default:
289 		return -ENOTSUPP;
290 	}
291 }
292 
293 /*
294  * gpiolib gpio_to_irq callback function. Creates a mapping between a GPIO pin
295  * and a virtual IRQ, if not already present.
296  */
297 static int rockchip_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
298 {
299 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
300 	unsigned int virq;
301 
302 	if (!bank->domain)
303 		return -ENXIO;
304 
305 	virq = irq_create_mapping(bank->domain, offset);
306 
307 	return (virq) ? : -ENXIO;
308 }
309 
310 static const struct gpio_chip rockchip_gpiolib_chip = {
311 	.request = gpiochip_generic_request,
312 	.free = gpiochip_generic_free,
313 	.set = rockchip_gpio_set,
314 	.get = rockchip_gpio_get,
315 	.get_direction	= rockchip_gpio_get_direction,
316 	.direction_input = rockchip_gpio_direction_input,
317 	.direction_output = rockchip_gpio_direction_output,
318 	.set_config = rockchip_gpio_set_config,
319 	.to_irq = rockchip_gpio_to_irq,
320 	.owner = THIS_MODULE,
321 };
322 
323 static void rockchip_irq_demux(struct irq_desc *desc)
324 {
325 	struct irq_chip *chip = irq_desc_get_chip(desc);
326 	struct rockchip_pin_bank *bank = irq_desc_get_handler_data(desc);
327 	u32 pend;
328 
329 	dev_dbg(bank->dev, "got irq for bank %s\n", bank->name);
330 
331 	chained_irq_enter(chip, desc);
332 
333 	pend = readl_relaxed(bank->reg_base + bank->gpio_regs->int_status);
334 
335 	while (pend) {
336 		unsigned int irq, virq;
337 
338 		irq = __ffs(pend);
339 		pend &= ~BIT(irq);
340 		virq = irq_find_mapping(bank->domain, irq);
341 
342 		if (!virq) {
343 			dev_err(bank->dev, "unmapped irq %d\n", irq);
344 			continue;
345 		}
346 
347 		dev_dbg(bank->dev, "handling irq %d\n", irq);
348 
349 		/*
350 		 * Triggering IRQ on both rising and falling edge
351 		 * needs manual intervention.
352 		 */
353 		if (bank->toggle_edge_mode & BIT(irq)) {
354 			u32 data, data_old, polarity;
355 			unsigned long flags;
356 
357 			data = readl_relaxed(bank->reg_base +
358 					     bank->gpio_regs->ext_port);
359 			do {
360 				raw_spin_lock_irqsave(&bank->slock, flags);
361 
362 				polarity = readl_relaxed(bank->reg_base +
363 							 bank->gpio_regs->int_polarity);
364 				if (data & BIT(irq))
365 					polarity &= ~BIT(irq);
366 				else
367 					polarity |= BIT(irq);
368 				writel(polarity,
369 				       bank->reg_base +
370 				       bank->gpio_regs->int_polarity);
371 
372 				raw_spin_unlock_irqrestore(&bank->slock, flags);
373 
374 				data_old = data;
375 				data = readl_relaxed(bank->reg_base +
376 						     bank->gpio_regs->ext_port);
377 			} while ((data & BIT(irq)) != (data_old & BIT(irq)));
378 		}
379 
380 		generic_handle_irq(virq);
381 	}
382 
383 	chained_irq_exit(chip, desc);
384 }
385 
386 static int rockchip_irq_set_type(struct irq_data *d, unsigned int type)
387 {
388 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
389 	struct rockchip_pin_bank *bank = gc->private;
390 	u32 mask = BIT(d->hwirq);
391 	u32 polarity;
392 	u32 level;
393 	u32 data;
394 	unsigned long flags;
395 	int ret = 0;
396 
397 	raw_spin_lock_irqsave(&bank->slock, flags);
398 
399 	rockchip_gpio_writel_bit(bank, d->hwirq, 0,
400 				 bank->gpio_regs->port_ddr);
401 
402 	raw_spin_unlock_irqrestore(&bank->slock, flags);
403 
404 	if (type & IRQ_TYPE_EDGE_BOTH)
405 		irq_set_handler_locked(d, handle_edge_irq);
406 	else
407 		irq_set_handler_locked(d, handle_level_irq);
408 
409 	raw_spin_lock_irqsave(&bank->slock, flags);
410 
411 	level = rockchip_gpio_readl(bank, bank->gpio_regs->int_type);
412 	polarity = rockchip_gpio_readl(bank, bank->gpio_regs->int_polarity);
413 
414 	if (type == IRQ_TYPE_EDGE_BOTH) {
415 		if (bank->gpio_type == GPIO_TYPE_V2) {
416 			rockchip_gpio_writel_bit(bank, d->hwirq, 1,
417 						 bank->gpio_regs->int_bothedge);
418 			goto out;
419 		} else {
420 			bank->toggle_edge_mode |= mask;
421 			level |= mask;
422 
423 			/*
424 			 * Determine gpio state. If 1 next interrupt should be
425 			 * falling otherwise rising.
426 			 */
427 			data = readl(bank->reg_base + bank->gpio_regs->ext_port);
428 			if (data & mask)
429 				polarity &= ~mask;
430 			else
431 				polarity |= mask;
432 		}
433 	} else {
434 		if (bank->gpio_type == GPIO_TYPE_V2) {
435 			rockchip_gpio_writel_bit(bank, d->hwirq, 0,
436 						 bank->gpio_regs->int_bothedge);
437 		} else {
438 			bank->toggle_edge_mode &= ~mask;
439 		}
440 		switch (type) {
441 		case IRQ_TYPE_EDGE_RISING:
442 			level |= mask;
443 			polarity |= mask;
444 			break;
445 		case IRQ_TYPE_EDGE_FALLING:
446 			level |= mask;
447 			polarity &= ~mask;
448 			break;
449 		case IRQ_TYPE_LEVEL_HIGH:
450 			level &= ~mask;
451 			polarity |= mask;
452 			break;
453 		case IRQ_TYPE_LEVEL_LOW:
454 			level &= ~mask;
455 			polarity &= ~mask;
456 			break;
457 		default:
458 			ret = -EINVAL;
459 			goto out;
460 		}
461 	}
462 
463 	rockchip_gpio_writel(bank, level, bank->gpio_regs->int_type);
464 	rockchip_gpio_writel(bank, polarity, bank->gpio_regs->int_polarity);
465 out:
466 	raw_spin_unlock_irqrestore(&bank->slock, flags);
467 
468 	return ret;
469 }
470 
471 static int rockchip_irq_reqres(struct irq_data *d)
472 {
473 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
474 	struct rockchip_pin_bank *bank = gc->private;
475 
476 	return gpiochip_reqres_irq(&bank->gpio_chip, d->hwirq);
477 }
478 
479 static void rockchip_irq_relres(struct irq_data *d)
480 {
481 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
482 	struct rockchip_pin_bank *bank = gc->private;
483 
484 	gpiochip_relres_irq(&bank->gpio_chip, d->hwirq);
485 }
486 
487 static void rockchip_irq_suspend(struct irq_data *d)
488 {
489 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
490 	struct rockchip_pin_bank *bank = gc->private;
491 
492 	bank->saved_masks = irq_reg_readl(gc, bank->gpio_regs->int_mask);
493 	irq_reg_writel(gc, ~gc->wake_active, bank->gpio_regs->int_mask);
494 }
495 
496 static void rockchip_irq_resume(struct irq_data *d)
497 {
498 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
499 	struct rockchip_pin_bank *bank = gc->private;
500 
501 	irq_reg_writel(gc, bank->saved_masks, bank->gpio_regs->int_mask);
502 }
503 
504 static void rockchip_irq_enable(struct irq_data *d)
505 {
506 	irq_gc_mask_clr_bit(d);
507 }
508 
509 static void rockchip_irq_disable(struct irq_data *d)
510 {
511 	irq_gc_mask_set_bit(d);
512 }
513 
514 static int rockchip_interrupts_register(struct rockchip_pin_bank *bank)
515 {
516 	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
517 	struct irq_chip_generic *gc;
518 	int ret;
519 
520 	bank->domain = irq_domain_add_linear(bank->of_node, 32,
521 					&irq_generic_chip_ops, NULL);
522 	if (!bank->domain) {
523 		dev_warn(bank->dev, "could not init irq domain for bank %s\n",
524 			 bank->name);
525 		return -EINVAL;
526 	}
527 
528 	ret = irq_alloc_domain_generic_chips(bank->domain, 32, 1,
529 					     "rockchip_gpio_irq",
530 					     handle_level_irq,
531 					     clr, 0, 0);
532 	if (ret) {
533 		dev_err(bank->dev, "could not alloc generic chips for bank %s\n",
534 			bank->name);
535 		irq_domain_remove(bank->domain);
536 		return -EINVAL;
537 	}
538 
539 	gc = irq_get_domain_generic_chip(bank->domain, 0);
540 	if (bank->gpio_type == GPIO_TYPE_V2) {
541 		gc->reg_writel = gpio_writel_v2;
542 		gc->reg_readl = gpio_readl_v2;
543 	}
544 
545 	gc->reg_base = bank->reg_base;
546 	gc->private = bank;
547 	gc->chip_types[0].regs.mask = bank->gpio_regs->int_mask;
548 	gc->chip_types[0].regs.ack = bank->gpio_regs->port_eoi;
549 	gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
550 	gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit;
551 	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_clr_bit;
552 	gc->chip_types[0].chip.irq_enable = rockchip_irq_enable;
553 	gc->chip_types[0].chip.irq_disable = rockchip_irq_disable;
554 	gc->chip_types[0].chip.irq_set_wake = irq_gc_set_wake;
555 	gc->chip_types[0].chip.irq_suspend = rockchip_irq_suspend;
556 	gc->chip_types[0].chip.irq_resume = rockchip_irq_resume;
557 	gc->chip_types[0].chip.irq_set_type = rockchip_irq_set_type;
558 	gc->chip_types[0].chip.irq_request_resources = rockchip_irq_reqres;
559 	gc->chip_types[0].chip.irq_release_resources = rockchip_irq_relres;
560 	gc->wake_enabled = IRQ_MSK(bank->nr_pins);
561 
562 	/*
563 	 * Linux assumes that all interrupts start out disabled/masked.
564 	 * Our driver only uses the concept of masked and always keeps
565 	 * things enabled, so for us that's all masked and all enabled.
566 	 */
567 	rockchip_gpio_writel(bank, 0xffffffff, bank->gpio_regs->int_mask);
568 	rockchip_gpio_writel(bank, 0xffffffff, bank->gpio_regs->port_eoi);
569 	rockchip_gpio_writel(bank, 0xffffffff, bank->gpio_regs->int_en);
570 	gc->mask_cache = 0xffffffff;
571 
572 	irq_set_chained_handler_and_data(bank->irq,
573 					 rockchip_irq_demux, bank);
574 
575 	return 0;
576 }
577 
578 static int rockchip_gpiolib_register(struct rockchip_pin_bank *bank)
579 {
580 	struct gpio_chip *gc;
581 	int ret;
582 
583 	bank->gpio_chip = rockchip_gpiolib_chip;
584 
585 	gc = &bank->gpio_chip;
586 	gc->base = bank->pin_base;
587 	gc->ngpio = bank->nr_pins;
588 	gc->label = bank->name;
589 	gc->parent = bank->dev;
590 
591 	ret = gpiochip_add_data(gc, bank);
592 	if (ret) {
593 		dev_err(bank->dev, "failed to add gpiochip %s, %d\n",
594 			gc->label, ret);
595 		return ret;
596 	}
597 
598 	/*
599 	 * For DeviceTree-supported systems, the gpio core checks the
600 	 * pinctrl's device node for the "gpio-ranges" property.
601 	 * If it is present, it takes care of adding the pin ranges
602 	 * for the driver. In this case the driver can skip ahead.
603 	 *
604 	 * In order to remain compatible with older, existing DeviceTree
605 	 * files which don't set the "gpio-ranges" property or systems that
606 	 * utilize ACPI the driver has to call gpiochip_add_pin_range().
607 	 */
608 	if (!of_property_read_bool(bank->of_node, "gpio-ranges")) {
609 		struct device_node *pctlnp = of_get_parent(bank->of_node);
610 		struct pinctrl_dev *pctldev = NULL;
611 
612 		if (!pctlnp)
613 			return -ENODATA;
614 
615 		pctldev = of_pinctrl_get(pctlnp);
616 		if (!pctldev)
617 			return -ENODEV;
618 
619 		ret = gpiochip_add_pin_range(gc, dev_name(pctldev->dev), 0,
620 					     gc->base, gc->ngpio);
621 		if (ret) {
622 			dev_err(bank->dev, "Failed to add pin range\n");
623 			goto fail;
624 		}
625 	}
626 
627 	ret = rockchip_interrupts_register(bank);
628 	if (ret) {
629 		dev_err(bank->dev, "failed to register interrupt, %d\n", ret);
630 		goto fail;
631 	}
632 
633 	return 0;
634 
635 fail:
636 	gpiochip_remove(&bank->gpio_chip);
637 
638 	return ret;
639 }
640 
641 static int rockchip_get_bank_data(struct rockchip_pin_bank *bank)
642 {
643 	struct resource res;
644 	int id = 0;
645 
646 	if (of_address_to_resource(bank->of_node, 0, &res)) {
647 		dev_err(bank->dev, "cannot find IO resource for bank\n");
648 		return -ENOENT;
649 	}
650 
651 	bank->reg_base = devm_ioremap_resource(bank->dev, &res);
652 	if (IS_ERR(bank->reg_base))
653 		return PTR_ERR(bank->reg_base);
654 
655 	bank->irq = irq_of_parse_and_map(bank->of_node, 0);
656 	if (!bank->irq)
657 		return -EINVAL;
658 
659 	bank->clk = of_clk_get(bank->of_node, 0);
660 	if (IS_ERR(bank->clk))
661 		return PTR_ERR(bank->clk);
662 
663 	clk_prepare_enable(bank->clk);
664 	id = readl(bank->reg_base + gpio_regs_v2.version_id);
665 
666 	/* If not gpio v2, that is default to v1. */
667 	if (id == GPIO_TYPE_V2) {
668 		bank->gpio_regs = &gpio_regs_v2;
669 		bank->gpio_type = GPIO_TYPE_V2;
670 		bank->db_clk = of_clk_get(bank->of_node, 1);
671 		if (IS_ERR(bank->db_clk)) {
672 			dev_err(bank->dev, "cannot find debounce clk\n");
673 			clk_disable_unprepare(bank->clk);
674 			return -EINVAL;
675 		}
676 	} else {
677 		bank->gpio_regs = &gpio_regs_v1;
678 		bank->gpio_type = GPIO_TYPE_V1;
679 	}
680 
681 	return 0;
682 }
683 
684 static struct rockchip_pin_bank *
685 rockchip_gpio_find_bank(struct pinctrl_dev *pctldev, int id)
686 {
687 	struct rockchip_pinctrl *info;
688 	struct rockchip_pin_bank *bank;
689 	int i, found = 0;
690 
691 	info = pinctrl_dev_get_drvdata(pctldev);
692 	bank = info->ctrl->pin_banks;
693 	for (i = 0; i < info->ctrl->nr_banks; i++, bank++) {
694 		if (bank->bank_num == id) {
695 			found = 1;
696 			break;
697 		}
698 	}
699 
700 	return found ? bank : NULL;
701 }
702 
703 static int rockchip_gpio_probe(struct platform_device *pdev)
704 {
705 	struct device *dev = &pdev->dev;
706 	struct device_node *np = dev->of_node;
707 	struct device_node *pctlnp = of_get_parent(np);
708 	struct pinctrl_dev *pctldev = NULL;
709 	struct rockchip_pin_bank *bank = NULL;
710 	struct rockchip_pin_deferred *cfg;
711 	static int gpio;
712 	int id, ret;
713 
714 	if (!np || !pctlnp)
715 		return -ENODEV;
716 
717 	pctldev = of_pinctrl_get(pctlnp);
718 	if (!pctldev)
719 		return -EPROBE_DEFER;
720 
721 	id = of_alias_get_id(np, "gpio");
722 	if (id < 0)
723 		id = gpio++;
724 
725 	bank = rockchip_gpio_find_bank(pctldev, id);
726 	if (!bank)
727 		return -EINVAL;
728 
729 	bank->dev = dev;
730 	bank->of_node = np;
731 
732 	raw_spin_lock_init(&bank->slock);
733 
734 	ret = rockchip_get_bank_data(bank);
735 	if (ret)
736 		return ret;
737 
738 	/*
739 	 * Prevent clashes with a deferred output setting
740 	 * being added right at this moment.
741 	 */
742 	mutex_lock(&bank->deferred_lock);
743 
744 	ret = rockchip_gpiolib_register(bank);
745 	if (ret) {
746 		clk_disable_unprepare(bank->clk);
747 		mutex_unlock(&bank->deferred_lock);
748 		return ret;
749 	}
750 
751 	while (!list_empty(&bank->deferred_pins)) {
752 		cfg = list_first_entry(&bank->deferred_pins,
753 				       struct rockchip_pin_deferred, head);
754 		list_del(&cfg->head);
755 
756 		switch (cfg->param) {
757 		case PIN_CONFIG_OUTPUT:
758 			ret = rockchip_gpio_direction_output(&bank->gpio_chip, cfg->pin, cfg->arg);
759 			if (ret)
760 				dev_warn(dev, "setting output pin %u to %u failed\n", cfg->pin,
761 					 cfg->arg);
762 			break;
763 		case PIN_CONFIG_INPUT_ENABLE:
764 			ret = rockchip_gpio_direction_input(&bank->gpio_chip, cfg->pin);
765 			if (ret)
766 				dev_warn(dev, "setting input pin %u failed\n", cfg->pin);
767 			break;
768 		default:
769 			dev_warn(dev, "unknown deferred config param %d\n", cfg->param);
770 			break;
771 		}
772 		kfree(cfg);
773 	}
774 
775 	mutex_unlock(&bank->deferred_lock);
776 
777 	platform_set_drvdata(pdev, bank);
778 	dev_info(dev, "probed %pOF\n", np);
779 
780 	return 0;
781 }
782 
783 static int rockchip_gpio_remove(struct platform_device *pdev)
784 {
785 	struct rockchip_pin_bank *bank = platform_get_drvdata(pdev);
786 
787 	clk_disable_unprepare(bank->clk);
788 	gpiochip_remove(&bank->gpio_chip);
789 
790 	return 0;
791 }
792 
793 static const struct of_device_id rockchip_gpio_match[] = {
794 	{ .compatible = "rockchip,gpio-bank", },
795 	{ .compatible = "rockchip,rk3188-gpio-bank0" },
796 	{ },
797 };
798 
799 static struct platform_driver rockchip_gpio_driver = {
800 	.probe		= rockchip_gpio_probe,
801 	.remove		= rockchip_gpio_remove,
802 	.driver		= {
803 		.name	= "rockchip-gpio",
804 		.of_match_table = rockchip_gpio_match,
805 	},
806 };
807 
808 static int __init rockchip_gpio_init(void)
809 {
810 	return platform_driver_register(&rockchip_gpio_driver);
811 }
812 postcore_initcall(rockchip_gpio_init);
813 
814 static void __exit rockchip_gpio_exit(void)
815 {
816 	platform_driver_unregister(&rockchip_gpio_driver);
817 }
818 module_exit(rockchip_gpio_exit);
819 
820 MODULE_DESCRIPTION("Rockchip gpio driver");
821 MODULE_ALIAS("platform:rockchip-gpio");
822 MODULE_LICENSE("GPL v2");
823 MODULE_DEVICE_TABLE(of, rockchip_gpio_match);
824