xref: /openbmc/linux/drivers/gpio/gpio-rockchip.c (revision b7b3c35e)
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/regmap.h>
23 
24 #include "../pinctrl/core.h"
25 #include "../pinctrl/pinctrl-rockchip.h"
26 
27 #define GPIO_TYPE_V1		(0)           /* GPIO Version ID reserved */
28 #define GPIO_TYPE_V2		(0x01000C2B)  /* GPIO Version ID 0x01000C2B */
29 
30 static const struct rockchip_gpio_regs gpio_regs_v1 = {
31 	.port_dr = 0x00,
32 	.port_ddr = 0x04,
33 	.int_en = 0x30,
34 	.int_mask = 0x34,
35 	.int_type = 0x38,
36 	.int_polarity = 0x3c,
37 	.int_status = 0x40,
38 	.int_rawstatus = 0x44,
39 	.debounce = 0x48,
40 	.port_eoi = 0x4c,
41 	.ext_port = 0x50,
42 };
43 
44 static const struct rockchip_gpio_regs gpio_regs_v2 = {
45 	.port_dr = 0x00,
46 	.port_ddr = 0x08,
47 	.int_en = 0x10,
48 	.int_mask = 0x18,
49 	.int_type = 0x20,
50 	.int_polarity = 0x28,
51 	.int_bothedge = 0x30,
52 	.int_status = 0x50,
53 	.int_rawstatus = 0x58,
54 	.debounce = 0x38,
55 	.dbclk_div_en = 0x40,
56 	.dbclk_div_con = 0x48,
57 	.port_eoi = 0x60,
58 	.ext_port = 0x70,
59 	.version_id = 0x78,
60 };
61 
62 static inline void gpio_writel_v2(u32 val, void __iomem *reg)
63 {
64 	writel((val & 0xffff) | 0xffff0000, reg);
65 	writel((val >> 16) | 0xffff0000, reg + 0x4);
66 }
67 
68 static inline u32 gpio_readl_v2(void __iomem *reg)
69 {
70 	return readl(reg + 0x4) << 16 | readl(reg);
71 }
72 
73 static inline void rockchip_gpio_writel(struct rockchip_pin_bank *bank,
74 					u32 value, unsigned int offset)
75 {
76 	void __iomem *reg = bank->reg_base + offset;
77 
78 	if (bank->gpio_type == GPIO_TYPE_V2)
79 		gpio_writel_v2(value, reg);
80 	else
81 		writel(value, reg);
82 }
83 
84 static inline u32 rockchip_gpio_readl(struct rockchip_pin_bank *bank,
85 				      unsigned int offset)
86 {
87 	void __iomem *reg = bank->reg_base + offset;
88 	u32 value;
89 
90 	if (bank->gpio_type == GPIO_TYPE_V2)
91 		value = gpio_readl_v2(reg);
92 	else
93 		value = readl(reg);
94 
95 	return value;
96 }
97 
98 static inline void rockchip_gpio_writel_bit(struct rockchip_pin_bank *bank,
99 					    u32 bit, u32 value,
100 					    unsigned int offset)
101 {
102 	void __iomem *reg = bank->reg_base + offset;
103 	u32 data;
104 
105 	if (bank->gpio_type == GPIO_TYPE_V2) {
106 		if (value)
107 			data = BIT(bit % 16) | BIT(bit % 16 + 16);
108 		else
109 			data = BIT(bit % 16 + 16);
110 		writel(data, bit >= 16 ? reg + 0x4 : reg);
111 	} else {
112 		data = readl(reg);
113 		data &= ~BIT(bit);
114 		if (value)
115 			data |= BIT(bit);
116 		writel(data, reg);
117 	}
118 }
119 
120 static inline u32 rockchip_gpio_readl_bit(struct rockchip_pin_bank *bank,
121 					  u32 bit, unsigned int offset)
122 {
123 	void __iomem *reg = bank->reg_base + offset;
124 	u32 data;
125 
126 	if (bank->gpio_type == GPIO_TYPE_V2) {
127 		data = readl(bit >= 16 ? reg + 0x4 : reg);
128 		data >>= bit % 16;
129 	} else {
130 		data = readl(reg);
131 		data >>= bit;
132 	}
133 
134 	return data & (0x1);
135 }
136 
137 static int rockchip_gpio_get_direction(struct gpio_chip *chip,
138 				       unsigned int offset)
139 {
140 	struct rockchip_pin_bank *bank = gpiochip_get_data(chip);
141 	u32 data;
142 
143 	data = rockchip_gpio_readl_bit(bank, offset, bank->gpio_regs->port_ddr);
144 	if (data)
145 		return GPIO_LINE_DIRECTION_OUT;
146 
147 	return GPIO_LINE_DIRECTION_IN;
148 }
149 
150 static int rockchip_gpio_set_direction(struct gpio_chip *chip,
151 				       unsigned int offset, bool input)
152 {
153 	struct rockchip_pin_bank *bank = gpiochip_get_data(chip);
154 	unsigned long flags;
155 	u32 data = input ? 0 : 1;
156 
157 	raw_spin_lock_irqsave(&bank->slock, flags);
158 	rockchip_gpio_writel_bit(bank, offset, data, bank->gpio_regs->port_ddr);
159 	raw_spin_unlock_irqrestore(&bank->slock, flags);
160 
161 	return 0;
162 }
163 
164 static void rockchip_gpio_set(struct gpio_chip *gc, unsigned int offset,
165 			      int value)
166 {
167 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
168 	unsigned long flags;
169 
170 	raw_spin_lock_irqsave(&bank->slock, flags);
171 	rockchip_gpio_writel_bit(bank, offset, value, bank->gpio_regs->port_dr);
172 	raw_spin_unlock_irqrestore(&bank->slock, flags);
173 }
174 
175 static int rockchip_gpio_get(struct gpio_chip *gc, unsigned int offset)
176 {
177 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
178 	u32 data;
179 
180 	data = readl(bank->reg_base + bank->gpio_regs->ext_port);
181 	data >>= offset;
182 	data &= 1;
183 
184 	return data;
185 }
186 
187 static int rockchip_gpio_set_debounce(struct gpio_chip *gc,
188 				      unsigned int offset,
189 				      unsigned int debounce)
190 {
191 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
192 	const struct rockchip_gpio_regs	*reg = bank->gpio_regs;
193 	unsigned long flags, div_reg, freq, max_debounce;
194 	bool div_debounce_support;
195 	unsigned int cur_div_reg;
196 	u64 div;
197 
198 	if (bank->gpio_type == GPIO_TYPE_V2 && !IS_ERR(bank->db_clk)) {
199 		div_debounce_support = true;
200 		freq = clk_get_rate(bank->db_clk);
201 		max_debounce = (GENMASK(23, 0) + 1) * 2 * 1000000 / freq;
202 		if (debounce > max_debounce)
203 			return -EINVAL;
204 
205 		div = debounce * freq;
206 		div_reg = DIV_ROUND_CLOSEST_ULL(div, 2 * USEC_PER_SEC) - 1;
207 	} else {
208 		div_debounce_support = false;
209 	}
210 
211 	raw_spin_lock_irqsave(&bank->slock, flags);
212 
213 	/* Only the v1 needs to configure div_en and div_con for dbclk */
214 	if (debounce) {
215 		if (div_debounce_support) {
216 			/* Configure the max debounce from consumers */
217 			cur_div_reg = readl(bank->reg_base +
218 					    reg->dbclk_div_con);
219 			if (cur_div_reg < div_reg)
220 				writel(div_reg, bank->reg_base +
221 				       reg->dbclk_div_con);
222 			rockchip_gpio_writel_bit(bank, offset, 1,
223 						 reg->dbclk_div_en);
224 		}
225 
226 		rockchip_gpio_writel_bit(bank, offset, 1, reg->debounce);
227 	} else {
228 		if (div_debounce_support)
229 			rockchip_gpio_writel_bit(bank, offset, 0,
230 						 reg->dbclk_div_en);
231 
232 		rockchip_gpio_writel_bit(bank, offset, 0, reg->debounce);
233 	}
234 
235 	raw_spin_unlock_irqrestore(&bank->slock, flags);
236 
237 	/* Enable or disable dbclk at last */
238 	if (div_debounce_support) {
239 		if (debounce)
240 			clk_prepare_enable(bank->db_clk);
241 		else
242 			clk_disable_unprepare(bank->db_clk);
243 	}
244 
245 	return 0;
246 }
247 
248 static int rockchip_gpio_direction_input(struct gpio_chip *gc,
249 					 unsigned int offset)
250 {
251 	return rockchip_gpio_set_direction(gc, offset, true);
252 }
253 
254 static int rockchip_gpio_direction_output(struct gpio_chip *gc,
255 					  unsigned int offset, int value)
256 {
257 	rockchip_gpio_set(gc, offset, value);
258 
259 	return rockchip_gpio_set_direction(gc, offset, false);
260 }
261 
262 /*
263  * gpiolib set_config callback function. The setting of the pin
264  * mux function as 'gpio output' will be handled by the pinctrl subsystem
265  * interface.
266  */
267 static int rockchip_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
268 				  unsigned long config)
269 {
270 	enum pin_config_param param = pinconf_to_config_param(config);
271 
272 	switch (param) {
273 	case PIN_CONFIG_INPUT_DEBOUNCE:
274 		rockchip_gpio_set_debounce(gc, offset, true);
275 		/*
276 		 * Rockchip's gpio could only support up to one period
277 		 * of the debounce clock(pclk), which is far away from
278 		 * satisftying the requirement, as pclk is usually near
279 		 * 100MHz shared by all peripherals. So the fact is it
280 		 * has crippled debounce capability could only be useful
281 		 * to prevent any spurious glitches from waking up the system
282 		 * if the gpio is conguired as wakeup interrupt source. Let's
283 		 * still return -ENOTSUPP as before, to make sure the caller
284 		 * of gpiod_set_debounce won't change its behaviour.
285 		 */
286 		return -ENOTSUPP;
287 	default:
288 		return -ENOTSUPP;
289 	}
290 }
291 
292 /*
293  * gpiolib gpio_to_irq callback function. Creates a mapping between a GPIO pin
294  * and a virtual IRQ, if not already present.
295  */
296 static int rockchip_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
297 {
298 	struct rockchip_pin_bank *bank = gpiochip_get_data(gc);
299 	unsigned int virq;
300 
301 	if (!bank->domain)
302 		return -ENXIO;
303 
304 	virq = irq_create_mapping(bank->domain, offset);
305 
306 	return (virq) ? : -ENXIO;
307 }
308 
309 static const struct gpio_chip rockchip_gpiolib_chip = {
310 	.request = gpiochip_generic_request,
311 	.free = gpiochip_generic_free,
312 	.set = rockchip_gpio_set,
313 	.get = rockchip_gpio_get,
314 	.get_direction	= rockchip_gpio_get_direction,
315 	.direction_input = rockchip_gpio_direction_input,
316 	.direction_output = rockchip_gpio_direction_output,
317 	.set_config = rockchip_gpio_set_config,
318 	.to_irq = rockchip_gpio_to_irq,
319 	.owner = THIS_MODULE,
320 };
321 
322 static void rockchip_irq_demux(struct irq_desc *desc)
323 {
324 	struct irq_chip *chip = irq_desc_get_chip(desc);
325 	struct rockchip_pin_bank *bank = irq_desc_get_handler_data(desc);
326 	u32 pend;
327 
328 	dev_dbg(bank->dev, "got irq for bank %s\n", bank->name);
329 
330 	chained_irq_enter(chip, desc);
331 
332 	pend = readl_relaxed(bank->reg_base + bank->gpio_regs->int_status);
333 
334 	while (pend) {
335 		unsigned int irq, virq;
336 
337 		irq = __ffs(pend);
338 		pend &= ~BIT(irq);
339 		virq = irq_find_mapping(bank->domain, irq);
340 
341 		if (!virq) {
342 			dev_err(bank->dev, "unmapped irq %d\n", irq);
343 			continue;
344 		}
345 
346 		dev_dbg(bank->dev, "handling irq %d\n", irq);
347 
348 		/*
349 		 * Triggering IRQ on both rising and falling edge
350 		 * needs manual intervention.
351 		 */
352 		if (bank->toggle_edge_mode & BIT(irq)) {
353 			u32 data, data_old, polarity;
354 			unsigned long flags;
355 
356 			data = readl_relaxed(bank->reg_base +
357 					     bank->gpio_regs->ext_port);
358 			do {
359 				raw_spin_lock_irqsave(&bank->slock, flags);
360 
361 				polarity = readl_relaxed(bank->reg_base +
362 							 bank->gpio_regs->int_polarity);
363 				if (data & BIT(irq))
364 					polarity &= ~BIT(irq);
365 				else
366 					polarity |= BIT(irq);
367 				writel(polarity,
368 				       bank->reg_base +
369 				       bank->gpio_regs->int_polarity);
370 
371 				raw_spin_unlock_irqrestore(&bank->slock, flags);
372 
373 				data_old = data;
374 				data = readl_relaxed(bank->reg_base +
375 						     bank->gpio_regs->ext_port);
376 			} while ((data & BIT(irq)) != (data_old & BIT(irq)));
377 		}
378 
379 		generic_handle_irq(virq);
380 	}
381 
382 	chained_irq_exit(chip, desc);
383 }
384 
385 static int rockchip_irq_set_type(struct irq_data *d, unsigned int type)
386 {
387 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
388 	struct rockchip_pin_bank *bank = gc->private;
389 	u32 mask = BIT(d->hwirq);
390 	u32 polarity;
391 	u32 level;
392 	u32 data;
393 	unsigned long flags;
394 	int ret = 0;
395 
396 	raw_spin_lock_irqsave(&bank->slock, flags);
397 
398 	rockchip_gpio_writel_bit(bank, d->hwirq, 0,
399 				 bank->gpio_regs->port_ddr);
400 
401 	raw_spin_unlock_irqrestore(&bank->slock, flags);
402 
403 	if (type & IRQ_TYPE_EDGE_BOTH)
404 		irq_set_handler_locked(d, handle_edge_irq);
405 	else
406 		irq_set_handler_locked(d, handle_level_irq);
407 
408 	raw_spin_lock_irqsave(&bank->slock, flags);
409 
410 	level = rockchip_gpio_readl(bank, bank->gpio_regs->int_type);
411 	polarity = rockchip_gpio_readl(bank, bank->gpio_regs->int_polarity);
412 
413 	switch (type) {
414 	case IRQ_TYPE_EDGE_BOTH:
415 		if (bank->gpio_type == GPIO_TYPE_V2) {
416 			bank->toggle_edge_mode &= ~mask;
417 			rockchip_gpio_writel_bit(bank, d->hwirq, 1,
418 						 bank->gpio_regs->int_bothedge);
419 			goto out;
420 		} else {
421 			bank->toggle_edge_mode |= mask;
422 			level |= mask;
423 
424 			/*
425 			 * Determine gpio state. If 1 next interrupt should be
426 			 * falling otherwise rising.
427 			 */
428 			data = readl(bank->reg_base + bank->gpio_regs->ext_port);
429 			if (data & mask)
430 				polarity &= ~mask;
431 			else
432 				polarity |= mask;
433 		}
434 		break;
435 	case IRQ_TYPE_EDGE_RISING:
436 		bank->toggle_edge_mode &= ~mask;
437 		level |= mask;
438 		polarity |= mask;
439 		break;
440 	case IRQ_TYPE_EDGE_FALLING:
441 		bank->toggle_edge_mode &= ~mask;
442 		level |= mask;
443 		polarity &= ~mask;
444 		break;
445 	case IRQ_TYPE_LEVEL_HIGH:
446 		bank->toggle_edge_mode &= ~mask;
447 		level &= ~mask;
448 		polarity |= mask;
449 		break;
450 	case IRQ_TYPE_LEVEL_LOW:
451 		bank->toggle_edge_mode &= ~mask;
452 		level &= ~mask;
453 		polarity &= ~mask;
454 		break;
455 	default:
456 		ret = -EINVAL;
457 		goto out;
458 	}
459 
460 	rockchip_gpio_writel(bank, level, bank->gpio_regs->int_type);
461 	rockchip_gpio_writel(bank, polarity, bank->gpio_regs->int_polarity);
462 out:
463 	raw_spin_unlock_irqrestore(&bank->slock, flags);
464 
465 	return ret;
466 }
467 
468 static int rockchip_irq_reqres(struct irq_data *d)
469 {
470 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
471 	struct rockchip_pin_bank *bank = gc->private;
472 
473 	return gpiochip_reqres_irq(&bank->gpio_chip, d->hwirq);
474 }
475 
476 static void rockchip_irq_relres(struct irq_data *d)
477 {
478 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
479 	struct rockchip_pin_bank *bank = gc->private;
480 
481 	gpiochip_relres_irq(&bank->gpio_chip, d->hwirq);
482 }
483 
484 static void rockchip_irq_suspend(struct irq_data *d)
485 {
486 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
487 	struct rockchip_pin_bank *bank = gc->private;
488 
489 	bank->saved_masks = irq_reg_readl(gc, bank->gpio_regs->int_mask);
490 	irq_reg_writel(gc, ~gc->wake_active, bank->gpio_regs->int_mask);
491 }
492 
493 static void rockchip_irq_resume(struct irq_data *d)
494 {
495 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
496 	struct rockchip_pin_bank *bank = gc->private;
497 
498 	irq_reg_writel(gc, bank->saved_masks, bank->gpio_regs->int_mask);
499 }
500 
501 static void rockchip_irq_enable(struct irq_data *d)
502 {
503 	irq_gc_mask_clr_bit(d);
504 }
505 
506 static void rockchip_irq_disable(struct irq_data *d)
507 {
508 	irq_gc_mask_set_bit(d);
509 }
510 
511 static int rockchip_interrupts_register(struct rockchip_pin_bank *bank)
512 {
513 	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
514 	struct irq_chip_generic *gc;
515 	int ret;
516 
517 	bank->domain = irq_domain_add_linear(bank->of_node, 32,
518 					&irq_generic_chip_ops, NULL);
519 	if (!bank->domain) {
520 		dev_warn(bank->dev, "could not init irq domain for bank %s\n",
521 			 bank->name);
522 		return -EINVAL;
523 	}
524 
525 	ret = irq_alloc_domain_generic_chips(bank->domain, 32, 1,
526 					     "rockchip_gpio_irq",
527 					     handle_level_irq,
528 					     clr, 0, 0);
529 	if (ret) {
530 		dev_err(bank->dev, "could not alloc generic chips for bank %s\n",
531 			bank->name);
532 		irq_domain_remove(bank->domain);
533 		return -EINVAL;
534 	}
535 
536 	gc = irq_get_domain_generic_chip(bank->domain, 0);
537 	if (bank->gpio_type == GPIO_TYPE_V2) {
538 		gc->reg_writel = gpio_writel_v2;
539 		gc->reg_readl = gpio_readl_v2;
540 	}
541 
542 	gc->reg_base = bank->reg_base;
543 	gc->private = bank;
544 	gc->chip_types[0].regs.mask = bank->gpio_regs->int_mask;
545 	gc->chip_types[0].regs.ack = bank->gpio_regs->port_eoi;
546 	gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
547 	gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit;
548 	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_clr_bit;
549 	gc->chip_types[0].chip.irq_enable = rockchip_irq_enable;
550 	gc->chip_types[0].chip.irq_disable = rockchip_irq_disable;
551 	gc->chip_types[0].chip.irq_set_wake = irq_gc_set_wake;
552 	gc->chip_types[0].chip.irq_suspend = rockchip_irq_suspend;
553 	gc->chip_types[0].chip.irq_resume = rockchip_irq_resume;
554 	gc->chip_types[0].chip.irq_set_type = rockchip_irq_set_type;
555 	gc->chip_types[0].chip.irq_request_resources = rockchip_irq_reqres;
556 	gc->chip_types[0].chip.irq_release_resources = rockchip_irq_relres;
557 	gc->wake_enabled = IRQ_MSK(bank->nr_pins);
558 
559 	/*
560 	 * Linux assumes that all interrupts start out disabled/masked.
561 	 * Our driver only uses the concept of masked and always keeps
562 	 * things enabled, so for us that's all masked and all enabled.
563 	 */
564 	rockchip_gpio_writel(bank, 0xffffffff, bank->gpio_regs->int_mask);
565 	rockchip_gpio_writel(bank, 0xffffffff, bank->gpio_regs->port_eoi);
566 	rockchip_gpio_writel(bank, 0xffffffff, bank->gpio_regs->int_en);
567 	gc->mask_cache = 0xffffffff;
568 
569 	irq_set_chained_handler_and_data(bank->irq,
570 					 rockchip_irq_demux, bank);
571 
572 	return 0;
573 }
574 
575 static int rockchip_gpiolib_register(struct rockchip_pin_bank *bank)
576 {
577 	struct gpio_chip *gc;
578 	int ret;
579 
580 	bank->gpio_chip = rockchip_gpiolib_chip;
581 
582 	gc = &bank->gpio_chip;
583 	gc->base = bank->pin_base;
584 	gc->ngpio = bank->nr_pins;
585 	gc->label = bank->name;
586 	gc->parent = bank->dev;
587 
588 	ret = gpiochip_add_data(gc, bank);
589 	if (ret) {
590 		dev_err(bank->dev, "failed to add gpiochip %s, %d\n",
591 			gc->label, ret);
592 		return ret;
593 	}
594 
595 	/*
596 	 * For DeviceTree-supported systems, the gpio core checks the
597 	 * pinctrl's device node for the "gpio-ranges" property.
598 	 * If it is present, it takes care of adding the pin ranges
599 	 * for the driver. In this case the driver can skip ahead.
600 	 *
601 	 * In order to remain compatible with older, existing DeviceTree
602 	 * files which don't set the "gpio-ranges" property or systems that
603 	 * utilize ACPI the driver has to call gpiochip_add_pin_range().
604 	 */
605 	if (!of_property_read_bool(bank->of_node, "gpio-ranges")) {
606 		struct device_node *pctlnp = of_get_parent(bank->of_node);
607 		struct pinctrl_dev *pctldev = NULL;
608 
609 		if (!pctlnp)
610 			return -ENODATA;
611 
612 		pctldev = of_pinctrl_get(pctlnp);
613 		if (!pctldev)
614 			return -ENODEV;
615 
616 		ret = gpiochip_add_pin_range(gc, dev_name(pctldev->dev), 0,
617 					     gc->base, gc->ngpio);
618 		if (ret) {
619 			dev_err(bank->dev, "Failed to add pin range\n");
620 			goto fail;
621 		}
622 	}
623 
624 	ret = rockchip_interrupts_register(bank);
625 	if (ret) {
626 		dev_err(bank->dev, "failed to register interrupt, %d\n", ret);
627 		goto fail;
628 	}
629 
630 	return 0;
631 
632 fail:
633 	gpiochip_remove(&bank->gpio_chip);
634 
635 	return ret;
636 }
637 
638 static int rockchip_get_bank_data(struct rockchip_pin_bank *bank)
639 {
640 	struct resource res;
641 	int id = 0;
642 
643 	if (of_address_to_resource(bank->of_node, 0, &res)) {
644 		dev_err(bank->dev, "cannot find IO resource for bank\n");
645 		return -ENOENT;
646 	}
647 
648 	bank->reg_base = devm_ioremap_resource(bank->dev, &res);
649 	if (IS_ERR(bank->reg_base))
650 		return PTR_ERR(bank->reg_base);
651 
652 	bank->irq = irq_of_parse_and_map(bank->of_node, 0);
653 	if (!bank->irq)
654 		return -EINVAL;
655 
656 	bank->clk = of_clk_get(bank->of_node, 0);
657 	if (IS_ERR(bank->clk))
658 		return PTR_ERR(bank->clk);
659 
660 	clk_prepare_enable(bank->clk);
661 	id = readl(bank->reg_base + gpio_regs_v2.version_id);
662 
663 	/* If not gpio v2, that is default to v1. */
664 	if (id == GPIO_TYPE_V2) {
665 		bank->gpio_regs = &gpio_regs_v2;
666 		bank->gpio_type = GPIO_TYPE_V2;
667 		bank->db_clk = of_clk_get(bank->of_node, 1);
668 		if (IS_ERR(bank->db_clk)) {
669 			dev_err(bank->dev, "cannot find debounce clk\n");
670 			clk_disable_unprepare(bank->clk);
671 			return -EINVAL;
672 		}
673 	} else {
674 		bank->gpio_regs = &gpio_regs_v1;
675 		bank->gpio_type = GPIO_TYPE_V1;
676 	}
677 
678 	return 0;
679 }
680 
681 static struct rockchip_pin_bank *
682 rockchip_gpio_find_bank(struct pinctrl_dev *pctldev, int id)
683 {
684 	struct rockchip_pinctrl *info;
685 	struct rockchip_pin_bank *bank;
686 	int i, found = 0;
687 
688 	info = pinctrl_dev_get_drvdata(pctldev);
689 	bank = info->ctrl->pin_banks;
690 	for (i = 0; i < info->ctrl->nr_banks; i++, bank++) {
691 		if (bank->bank_num == id) {
692 			found = 1;
693 			break;
694 		}
695 	}
696 
697 	return found ? bank : NULL;
698 }
699 
700 static int rockchip_gpio_probe(struct platform_device *pdev)
701 {
702 	struct device *dev = &pdev->dev;
703 	struct device_node *np = dev->of_node;
704 	struct device_node *pctlnp = of_get_parent(np);
705 	struct pinctrl_dev *pctldev = NULL;
706 	struct rockchip_pin_bank *bank = NULL;
707 	struct rockchip_pin_output_deferred *cfg;
708 	static int gpio;
709 	int id, ret;
710 
711 	if (!np || !pctlnp)
712 		return -ENODEV;
713 
714 	pctldev = of_pinctrl_get(pctlnp);
715 	if (!pctldev)
716 		return -EPROBE_DEFER;
717 
718 	id = of_alias_get_id(np, "gpio");
719 	if (id < 0)
720 		id = gpio++;
721 
722 	bank = rockchip_gpio_find_bank(pctldev, id);
723 	if (!bank)
724 		return -EINVAL;
725 
726 	bank->dev = dev;
727 	bank->of_node = np;
728 
729 	raw_spin_lock_init(&bank->slock);
730 
731 	ret = rockchip_get_bank_data(bank);
732 	if (ret)
733 		return ret;
734 
735 	/*
736 	 * Prevent clashes with a deferred output setting
737 	 * being added right at this moment.
738 	 */
739 	mutex_lock(&bank->deferred_lock);
740 
741 	ret = rockchip_gpiolib_register(bank);
742 	if (ret) {
743 		clk_disable_unprepare(bank->clk);
744 		mutex_unlock(&bank->deferred_lock);
745 		return ret;
746 	}
747 
748 	while (!list_empty(&bank->deferred_output)) {
749 		cfg = list_first_entry(&bank->deferred_output,
750 				       struct rockchip_pin_output_deferred, head);
751 		list_del(&cfg->head);
752 
753 		ret = rockchip_gpio_direction_output(&bank->gpio_chip, cfg->pin, cfg->arg);
754 		if (ret)
755 			dev_warn(dev, "setting output pin %u to %u failed\n", cfg->pin, cfg->arg);
756 
757 		kfree(cfg);
758 	}
759 
760 	mutex_unlock(&bank->deferred_lock);
761 
762 	platform_set_drvdata(pdev, bank);
763 	dev_info(dev, "probed %pOF\n", np);
764 
765 	return 0;
766 }
767 
768 static int rockchip_gpio_remove(struct platform_device *pdev)
769 {
770 	struct rockchip_pin_bank *bank = platform_get_drvdata(pdev);
771 
772 	clk_disable_unprepare(bank->clk);
773 	gpiochip_remove(&bank->gpio_chip);
774 
775 	return 0;
776 }
777 
778 static const struct of_device_id rockchip_gpio_match[] = {
779 	{ .compatible = "rockchip,gpio-bank", },
780 	{ .compatible = "rockchip,rk3188-gpio-bank0" },
781 	{ },
782 };
783 
784 static struct platform_driver rockchip_gpio_driver = {
785 	.probe		= rockchip_gpio_probe,
786 	.remove		= rockchip_gpio_remove,
787 	.driver		= {
788 		.name	= "rockchip-gpio",
789 		.of_match_table = rockchip_gpio_match,
790 	},
791 };
792 
793 static int __init rockchip_gpio_init(void)
794 {
795 	return platform_driver_register(&rockchip_gpio_driver);
796 }
797 postcore_initcall(rockchip_gpio_init);
798 
799 static void __exit rockchip_gpio_exit(void)
800 {
801 	platform_driver_unregister(&rockchip_gpio_driver);
802 }
803 module_exit(rockchip_gpio_exit);
804 
805 MODULE_DESCRIPTION("Rockchip gpio driver");
806 MODULE_ALIAS("platform:rockchip-gpio");
807 MODULE_LICENSE("GPL v2");
808 MODULE_DEVICE_TABLE(of, rockchip_gpio_match);
809