1 /*
2  * Copyright (C) 2014-2015 Broadcom Corporation
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation version 2.
7  *
8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9  * kind, whether express or implied; without even the implied warranty
10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * This file contains the Broadcom Iproc GPIO driver that supports 3
14  * GPIO controllers on Iproc including the ASIU GPIO controller, the
15  * chipCommonG GPIO controller, and the always-on GPIO controller. Basic
16  * PINCONF such as bias pull up/down, and drive strength are also supported
17  * in this driver.
18  *
19  * It provides the functionality where pins from the GPIO can be
20  * individually muxed to GPIO function, if individual pad
21  * configuration is supported, through the interaction with respective
22  * SoCs IOMUX controller.
23  */
24 
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
27 #include <linux/interrupt.h>
28 #include <linux/io.h>
29 #include <linux/gpio.h>
30 #include <linux/ioport.h>
31 #include <linux/of_device.h>
32 #include <linux/of_irq.h>
33 #include <linux/pinctrl/pinctrl.h>
34 #include <linux/pinctrl/pinconf.h>
35 #include <linux/pinctrl/pinconf-generic.h>
36 
37 #include "../pinctrl-utils.h"
38 
39 #define IPROC_GPIO_DATA_IN_OFFSET   0x00
40 #define IPROC_GPIO_DATA_OUT_OFFSET  0x04
41 #define IPROC_GPIO_OUT_EN_OFFSET    0x08
42 #define IPROC_GPIO_INT_TYPE_OFFSET  0x0c
43 #define IPROC_GPIO_INT_DE_OFFSET    0x10
44 #define IPROC_GPIO_INT_EDGE_OFFSET  0x14
45 #define IPROC_GPIO_INT_MSK_OFFSET   0x18
46 #define IPROC_GPIO_INT_STAT_OFFSET  0x1c
47 #define IPROC_GPIO_INT_MSTAT_OFFSET 0x20
48 #define IPROC_GPIO_INT_CLR_OFFSET   0x24
49 #define IPROC_GPIO_PAD_RES_OFFSET   0x34
50 #define IPROC_GPIO_RES_EN_OFFSET    0x38
51 
52 /* drive strength control for ASIU GPIO */
53 #define IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET 0x58
54 
55 /* drive strength control for CCM/CRMU (AON) GPIO */
56 #define IPROC_GPIO_DRV0_CTRL_OFFSET  0x00
57 
58 #define GPIO_BANK_SIZE 0x200
59 #define NGPIOS_PER_BANK 32
60 #define GPIO_BANK(pin) ((pin) / NGPIOS_PER_BANK)
61 
62 #define IPROC_GPIO_REG(pin, reg) (GPIO_BANK(pin) * GPIO_BANK_SIZE + (reg))
63 #define IPROC_GPIO_SHIFT(pin) ((pin) % NGPIOS_PER_BANK)
64 
65 #define GPIO_DRV_STRENGTH_BIT_SHIFT  20
66 #define GPIO_DRV_STRENGTH_BITS       3
67 #define GPIO_DRV_STRENGTH_BIT_MASK   ((1 << GPIO_DRV_STRENGTH_BITS) - 1)
68 
69 /*
70  * Iproc GPIO core
71  *
72  * @dev: pointer to device
73  * @base: I/O register base for Iproc GPIO controller
74  * @io_ctrl: I/O register base for certain type of Iproc GPIO controller that
75  * has the PINCONF support implemented outside of the GPIO block
76  * @lock: lock to protect access to I/O registers
77  * @gc: GPIO chip
78  * @num_banks: number of GPIO banks, each bank supports up to 32 GPIOs
79  * @pinmux_is_supported: flag to indicate this GPIO controller contains pins
80  * that can be individually muxed to GPIO
81  * @pctl: pointer to pinctrl_dev
82  * @pctldesc: pinctrl descriptor
83  */
84 struct iproc_gpio {
85 	struct device *dev;
86 
87 	void __iomem *base;
88 	void __iomem *io_ctrl;
89 
90 	spinlock_t lock;
91 
92 	struct gpio_chip gc;
93 	unsigned num_banks;
94 
95 	bool pinmux_is_supported;
96 
97 	struct pinctrl_dev *pctl;
98 	struct pinctrl_desc pctldesc;
99 };
100 
101 static inline struct iproc_gpio *to_iproc_gpio(struct gpio_chip *gc)
102 {
103 	return container_of(gc, struct iproc_gpio, gc);
104 }
105 
106 /*
107  * Mapping from PINCONF pins to GPIO pins is 1-to-1
108  */
109 static inline unsigned iproc_pin_to_gpio(unsigned pin)
110 {
111 	return pin;
112 }
113 
114 /**
115  *  iproc_set_bit - set or clear one bit (corresponding to the GPIO pin) in a
116  *  Iproc GPIO register
117  *
118  *  @iproc_gpio: Iproc GPIO device
119  *  @reg: register offset
120  *  @gpio: GPIO pin
121  *  @set: set or clear
122  */
123 static inline void iproc_set_bit(struct iproc_gpio *chip, unsigned int reg,
124 				  unsigned gpio, bool set)
125 {
126 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
127 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
128 	u32 val;
129 
130 	val = readl(chip->base + offset);
131 	if (set)
132 		val |= BIT(shift);
133 	else
134 		val &= ~BIT(shift);
135 	writel(val, chip->base + offset);
136 }
137 
138 static inline bool iproc_get_bit(struct iproc_gpio *chip, unsigned int reg,
139 				  unsigned gpio)
140 {
141 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
142 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
143 
144 	return !!(readl(chip->base + offset) & BIT(shift));
145 }
146 
147 static void iproc_gpio_irq_handler(struct irq_desc *desc)
148 {
149 	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
150 	struct iproc_gpio *chip = to_iproc_gpio(gc);
151 	struct irq_chip *irq_chip = irq_desc_get_chip(desc);
152 	int i, bit;
153 
154 	chained_irq_enter(irq_chip, desc);
155 
156 	/* go through the entire GPIO banks and handle all interrupts */
157 	for (i = 0; i < chip->num_banks; i++) {
158 		unsigned long val = readl(chip->base + (i * GPIO_BANK_SIZE) +
159 					  IPROC_GPIO_INT_MSTAT_OFFSET);
160 
161 		for_each_set_bit(bit, &val, NGPIOS_PER_BANK) {
162 			unsigned pin = NGPIOS_PER_BANK * i + bit;
163 			int child_irq = irq_find_mapping(gc->irqdomain, pin);
164 
165 			/*
166 			 * Clear the interrupt before invoking the
167 			 * handler, so we do not leave any window
168 			 */
169 			writel(BIT(bit), chip->base + (i * GPIO_BANK_SIZE) +
170 			       IPROC_GPIO_INT_CLR_OFFSET);
171 
172 			generic_handle_irq(child_irq);
173 		}
174 	}
175 
176 	chained_irq_exit(irq_chip, desc);
177 }
178 
179 
180 static void iproc_gpio_irq_ack(struct irq_data *d)
181 {
182 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
183 	struct iproc_gpio *chip = to_iproc_gpio(gc);
184 	unsigned gpio = d->hwirq;
185 	unsigned int offset = IPROC_GPIO_REG(gpio,
186 			IPROC_GPIO_INT_CLR_OFFSET);
187 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
188 	u32 val = BIT(shift);
189 
190 	writel(val, chip->base + offset);
191 }
192 
193 /**
194  *  iproc_gpio_irq_set_mask - mask/unmask a GPIO interrupt
195  *
196  *  @d: IRQ chip data
197  *  @unmask: mask/unmask GPIO interrupt
198  */
199 static void iproc_gpio_irq_set_mask(struct irq_data *d, bool unmask)
200 {
201 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
202 	struct iproc_gpio *chip = to_iproc_gpio(gc);
203 	unsigned gpio = d->hwirq;
204 
205 	iproc_set_bit(chip, IPROC_GPIO_INT_MSK_OFFSET, gpio, unmask);
206 }
207 
208 static void iproc_gpio_irq_mask(struct irq_data *d)
209 {
210 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
211 	struct iproc_gpio *chip = to_iproc_gpio(gc);
212 	unsigned long flags;
213 
214 	spin_lock_irqsave(&chip->lock, flags);
215 	iproc_gpio_irq_set_mask(d, false);
216 	spin_unlock_irqrestore(&chip->lock, flags);
217 }
218 
219 static void iproc_gpio_irq_unmask(struct irq_data *d)
220 {
221 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
222 	struct iproc_gpio *chip = to_iproc_gpio(gc);
223 	unsigned long flags;
224 
225 	spin_lock_irqsave(&chip->lock, flags);
226 	iproc_gpio_irq_set_mask(d, true);
227 	spin_unlock_irqrestore(&chip->lock, flags);
228 }
229 
230 static int iproc_gpio_irq_set_type(struct irq_data *d, unsigned int type)
231 {
232 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
233 	struct iproc_gpio *chip = to_iproc_gpio(gc);
234 	unsigned gpio = d->hwirq;
235 	bool level_triggered = false;
236 	bool dual_edge = false;
237 	bool rising_or_high = false;
238 	unsigned long flags;
239 
240 	switch (type & IRQ_TYPE_SENSE_MASK) {
241 	case IRQ_TYPE_EDGE_RISING:
242 		rising_or_high = true;
243 		break;
244 
245 	case IRQ_TYPE_EDGE_FALLING:
246 		break;
247 
248 	case IRQ_TYPE_EDGE_BOTH:
249 		dual_edge = true;
250 		break;
251 
252 	case IRQ_TYPE_LEVEL_HIGH:
253 		level_triggered = true;
254 		rising_or_high = true;
255 		break;
256 
257 	case IRQ_TYPE_LEVEL_LOW:
258 		level_triggered = true;
259 		break;
260 
261 	default:
262 		dev_err(chip->dev, "invalid GPIO IRQ type 0x%x\n",
263 			type);
264 		return -EINVAL;
265 	}
266 
267 	spin_lock_irqsave(&chip->lock, flags);
268 	iproc_set_bit(chip, IPROC_GPIO_INT_TYPE_OFFSET, gpio,
269 		       level_triggered);
270 	iproc_set_bit(chip, IPROC_GPIO_INT_DE_OFFSET, gpio, dual_edge);
271 	iproc_set_bit(chip, IPROC_GPIO_INT_EDGE_OFFSET, gpio,
272 		       rising_or_high);
273 	spin_unlock_irqrestore(&chip->lock, flags);
274 
275 	dev_dbg(chip->dev,
276 		"gpio:%u level_triggered:%d dual_edge:%d rising_or_high:%d\n",
277 		gpio, level_triggered, dual_edge, rising_or_high);
278 
279 	return 0;
280 }
281 
282 static struct irq_chip iproc_gpio_irq_chip = {
283 	.name = "bcm-iproc-gpio",
284 	.irq_ack = iproc_gpio_irq_ack,
285 	.irq_mask = iproc_gpio_irq_mask,
286 	.irq_unmask = iproc_gpio_irq_unmask,
287 	.irq_set_type = iproc_gpio_irq_set_type,
288 };
289 
290 /*
291  * Request the Iproc IOMUX pinmux controller to mux individual pins to GPIO
292  */
293 static int iproc_gpio_request(struct gpio_chip *gc, unsigned offset)
294 {
295 	struct iproc_gpio *chip = to_iproc_gpio(gc);
296 	unsigned gpio = gc->base + offset;
297 
298 	/* not all Iproc GPIO pins can be muxed individually */
299 	if (!chip->pinmux_is_supported)
300 		return 0;
301 
302 	return pinctrl_request_gpio(gpio);
303 }
304 
305 static void iproc_gpio_free(struct gpio_chip *gc, unsigned offset)
306 {
307 	struct iproc_gpio *chip = to_iproc_gpio(gc);
308 	unsigned gpio = gc->base + offset;
309 
310 	if (!chip->pinmux_is_supported)
311 		return;
312 
313 	pinctrl_free_gpio(gpio);
314 }
315 
316 static int iproc_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
317 {
318 	struct iproc_gpio *chip = to_iproc_gpio(gc);
319 	unsigned long flags;
320 
321 	spin_lock_irqsave(&chip->lock, flags);
322 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, false);
323 	spin_unlock_irqrestore(&chip->lock, flags);
324 
325 	dev_dbg(chip->dev, "gpio:%u set input\n", gpio);
326 
327 	return 0;
328 }
329 
330 static int iproc_gpio_direction_output(struct gpio_chip *gc, unsigned gpio,
331 					int val)
332 {
333 	struct iproc_gpio *chip = to_iproc_gpio(gc);
334 	unsigned long flags;
335 
336 	spin_lock_irqsave(&chip->lock, flags);
337 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, true);
338 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
339 	spin_unlock_irqrestore(&chip->lock, flags);
340 
341 	dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val);
342 
343 	return 0;
344 }
345 
346 static void iproc_gpio_set(struct gpio_chip *gc, unsigned gpio, int val)
347 {
348 	struct iproc_gpio *chip = to_iproc_gpio(gc);
349 	unsigned long flags;
350 
351 	spin_lock_irqsave(&chip->lock, flags);
352 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
353 	spin_unlock_irqrestore(&chip->lock, flags);
354 
355 	dev_dbg(chip->dev, "gpio:%u set, value:%d\n", gpio, val);
356 }
357 
358 static int iproc_gpio_get(struct gpio_chip *gc, unsigned gpio)
359 {
360 	struct iproc_gpio *chip = to_iproc_gpio(gc);
361 	unsigned int offset = IPROC_GPIO_REG(gpio,
362 					      IPROC_GPIO_DATA_IN_OFFSET);
363 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
364 
365 	return !!(readl(chip->base + offset) & BIT(shift));
366 }
367 
368 static int iproc_get_groups_count(struct pinctrl_dev *pctldev)
369 {
370 	return 1;
371 }
372 
373 /*
374  * Only one group: "gpio_grp", since this local pinctrl device only performs
375  * GPIO specific PINCONF configurations
376  */
377 static const char *iproc_get_group_name(struct pinctrl_dev *pctldev,
378 					 unsigned selector)
379 {
380 	return "gpio_grp";
381 }
382 
383 static const struct pinctrl_ops iproc_pctrl_ops = {
384 	.get_groups_count = iproc_get_groups_count,
385 	.get_group_name = iproc_get_group_name,
386 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
387 	.dt_free_map = pinctrl_utils_dt_free_map,
388 };
389 
390 static int iproc_gpio_set_pull(struct iproc_gpio *chip, unsigned gpio,
391 				bool disable, bool pull_up)
392 {
393 	unsigned long flags;
394 
395 	spin_lock_irqsave(&chip->lock, flags);
396 
397 	if (disable) {
398 		iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio, false);
399 	} else {
400 		iproc_set_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio,
401 			       pull_up);
402 		iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio, true);
403 	}
404 
405 	spin_unlock_irqrestore(&chip->lock, flags);
406 
407 	dev_dbg(chip->dev, "gpio:%u set pullup:%d\n", gpio, pull_up);
408 
409 	return 0;
410 }
411 
412 static void iproc_gpio_get_pull(struct iproc_gpio *chip, unsigned gpio,
413 				 bool *disable, bool *pull_up)
414 {
415 	unsigned long flags;
416 
417 	spin_lock_irqsave(&chip->lock, flags);
418 	*disable = !iproc_get_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio);
419 	*pull_up = iproc_get_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio);
420 	spin_unlock_irqrestore(&chip->lock, flags);
421 }
422 
423 static int iproc_gpio_set_strength(struct iproc_gpio *chip, unsigned gpio,
424 				    unsigned strength)
425 {
426 	void __iomem *base;
427 	unsigned int i, offset, shift;
428 	u32 val;
429 	unsigned long flags;
430 
431 	/* make sure drive strength is supported */
432 	if (strength < 2 ||  strength > 16 || (strength % 2))
433 		return -ENOTSUPP;
434 
435 	if (chip->io_ctrl) {
436 		base = chip->io_ctrl;
437 		offset = IPROC_GPIO_DRV0_CTRL_OFFSET;
438 	} else {
439 		base = chip->base;
440 		offset = IPROC_GPIO_REG(gpio,
441 					 IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET);
442 	}
443 
444 	shift = IPROC_GPIO_SHIFT(gpio);
445 
446 	dev_dbg(chip->dev, "gpio:%u set drive strength:%d mA\n", gpio,
447 		strength);
448 
449 	spin_lock_irqsave(&chip->lock, flags);
450 	strength = (strength / 2) - 1;
451 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
452 		val = readl(base + offset);
453 		val &= ~BIT(shift);
454 		val |= ((strength >> i) & 0x1) << shift;
455 		writel(val, base + offset);
456 		offset += 4;
457 	}
458 	spin_unlock_irqrestore(&chip->lock, flags);
459 
460 	return 0;
461 }
462 
463 static int iproc_gpio_get_strength(struct iproc_gpio *chip, unsigned gpio,
464 				    u16 *strength)
465 {
466 	void __iomem *base;
467 	unsigned int i, offset, shift;
468 	u32 val;
469 	unsigned long flags;
470 
471 	if (chip->io_ctrl) {
472 		base = chip->io_ctrl;
473 		offset = IPROC_GPIO_DRV0_CTRL_OFFSET;
474 	} else {
475 		base = chip->base;
476 		offset = IPROC_GPIO_REG(gpio,
477 					 IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET);
478 	}
479 
480 	shift = IPROC_GPIO_SHIFT(gpio);
481 
482 	spin_lock_irqsave(&chip->lock, flags);
483 	*strength = 0;
484 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
485 		val = readl(base + offset) & BIT(shift);
486 		val >>= shift;
487 		*strength += (val << i);
488 		offset += 4;
489 	}
490 
491 	/* convert to mA */
492 	*strength = (*strength + 1) * 2;
493 	spin_unlock_irqrestore(&chip->lock, flags);
494 
495 	return 0;
496 }
497 
498 static int iproc_pin_config_get(struct pinctrl_dev *pctldev, unsigned pin,
499 				 unsigned long *config)
500 {
501 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
502 	enum pin_config_param param = pinconf_to_config_param(*config);
503 	unsigned gpio = iproc_pin_to_gpio(pin);
504 	u16 arg;
505 	bool disable, pull_up;
506 	int ret;
507 
508 	switch (param) {
509 	case PIN_CONFIG_BIAS_DISABLE:
510 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
511 		if (disable)
512 			return 0;
513 		else
514 			return -EINVAL;
515 
516 	case PIN_CONFIG_BIAS_PULL_UP:
517 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
518 		if (!disable && pull_up)
519 			return 0;
520 		else
521 			return -EINVAL;
522 
523 	case PIN_CONFIG_BIAS_PULL_DOWN:
524 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
525 		if (!disable && !pull_up)
526 			return 0;
527 		else
528 			return -EINVAL;
529 
530 	case PIN_CONFIG_DRIVE_STRENGTH:
531 		ret = iproc_gpio_get_strength(chip, gpio, &arg);
532 		if (ret)
533 			return ret;
534 		*config = pinconf_to_config_packed(param, arg);
535 
536 		return 0;
537 
538 	default:
539 		return -ENOTSUPP;
540 	}
541 
542 	return -ENOTSUPP;
543 }
544 
545 static int iproc_pin_config_set(struct pinctrl_dev *pctldev, unsigned pin,
546 				 unsigned long *configs, unsigned num_configs)
547 {
548 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
549 	enum pin_config_param param;
550 	u16 arg;
551 	unsigned i, gpio = iproc_pin_to_gpio(pin);
552 	int ret = -ENOTSUPP;
553 
554 	for (i = 0; i < num_configs; i++) {
555 		param = pinconf_to_config_param(configs[i]);
556 		arg = pinconf_to_config_argument(configs[i]);
557 
558 		switch (param) {
559 		case PIN_CONFIG_BIAS_DISABLE:
560 			ret = iproc_gpio_set_pull(chip, gpio, true, false);
561 			if (ret < 0)
562 				goto out;
563 			break;
564 
565 		case PIN_CONFIG_BIAS_PULL_UP:
566 			ret = iproc_gpio_set_pull(chip, gpio, false, true);
567 			if (ret < 0)
568 				goto out;
569 			break;
570 
571 		case PIN_CONFIG_BIAS_PULL_DOWN:
572 			ret = iproc_gpio_set_pull(chip, gpio, false, false);
573 			if (ret < 0)
574 				goto out;
575 			break;
576 
577 		case PIN_CONFIG_DRIVE_STRENGTH:
578 			ret = iproc_gpio_set_strength(chip, gpio, arg);
579 			if (ret < 0)
580 				goto out;
581 			break;
582 
583 		default:
584 			dev_err(chip->dev, "invalid configuration\n");
585 			return -ENOTSUPP;
586 		}
587 	} /* for each config */
588 
589 out:
590 	return ret;
591 }
592 
593 static const struct pinconf_ops iproc_pconf_ops = {
594 	.is_generic = true,
595 	.pin_config_get = iproc_pin_config_get,
596 	.pin_config_set = iproc_pin_config_set,
597 };
598 
599 /*
600  * Iproc GPIO controller supports some PINCONF related configurations such as
601  * pull up, pull down, and drive strength, when the pin is configured to GPIO
602  *
603  * Here a local pinctrl device is created with simple 1-to-1 pin mapping to the
604  * local GPIO pins
605  */
606 static int iproc_gpio_register_pinconf(struct iproc_gpio *chip)
607 {
608 	struct pinctrl_desc *pctldesc = &chip->pctldesc;
609 	struct pinctrl_pin_desc *pins;
610 	struct gpio_chip *gc = &chip->gc;
611 	int i;
612 
613 	pins = devm_kcalloc(chip->dev, gc->ngpio, sizeof(*pins), GFP_KERNEL);
614 	if (!pins)
615 		return -ENOMEM;
616 
617 	for (i = 0; i < gc->ngpio; i++) {
618 		pins[i].number = i;
619 		pins[i].name = devm_kasprintf(chip->dev, GFP_KERNEL,
620 					      "gpio-%d", i);
621 		if (!pins[i].name)
622 			return -ENOMEM;
623 	}
624 
625 	pctldesc->name = dev_name(chip->dev);
626 	pctldesc->pctlops = &iproc_pctrl_ops;
627 	pctldesc->pins = pins;
628 	pctldesc->npins = gc->ngpio;
629 	pctldesc->confops = &iproc_pconf_ops;
630 
631 	chip->pctl = pinctrl_register(pctldesc, chip->dev, chip);
632 	if (IS_ERR(chip->pctl)) {
633 		dev_err(chip->dev, "unable to register pinctrl device\n");
634 		return PTR_ERR(chip->pctl);
635 	}
636 
637 	return 0;
638 }
639 
640 static void iproc_gpio_unregister_pinconf(struct iproc_gpio *chip)
641 {
642 	pinctrl_unregister(chip->pctl);
643 }
644 
645 static const struct of_device_id iproc_gpio_of_match[] = {
646 	{ .compatible = "brcm,cygnus-ccm-gpio" },
647 	{ .compatible = "brcm,cygnus-asiu-gpio" },
648 	{ .compatible = "brcm,cygnus-crmu-gpio" },
649 	{ .compatible = "brcm,iproc-gpio" },
650 	{ }
651 };
652 
653 static int iproc_gpio_probe(struct platform_device *pdev)
654 {
655 	struct device *dev = &pdev->dev;
656 	struct resource *res;
657 	struct iproc_gpio *chip;
658 	struct gpio_chip *gc;
659 	u32 ngpios;
660 	int irq, ret;
661 
662 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
663 	if (!chip)
664 		return -ENOMEM;
665 
666 	chip->dev = dev;
667 	platform_set_drvdata(pdev, chip);
668 
669 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
670 	chip->base = devm_ioremap_resource(dev, res);
671 	if (IS_ERR(chip->base)) {
672 		dev_err(dev, "unable to map I/O memory\n");
673 		return PTR_ERR(chip->base);
674 	}
675 
676 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
677 	if (res) {
678 		chip->io_ctrl = devm_ioremap_resource(dev, res);
679 		if (IS_ERR(chip->io_ctrl)) {
680 			dev_err(dev, "unable to map I/O memory\n");
681 			return PTR_ERR(chip->io_ctrl);
682 		}
683 	}
684 
685 	if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) {
686 		dev_err(&pdev->dev, "missing ngpios DT property\n");
687 		return -ENODEV;
688 	}
689 
690 	spin_lock_init(&chip->lock);
691 
692 	gc = &chip->gc;
693 	gc->base = -1;
694 	gc->ngpio = ngpios;
695 	chip->num_banks = (ngpios + NGPIOS_PER_BANK - 1) / NGPIOS_PER_BANK;
696 	gc->label = dev_name(dev);
697 	gc->parent = dev;
698 	gc->of_node = dev->of_node;
699 	gc->request = iproc_gpio_request;
700 	gc->free = iproc_gpio_free;
701 	gc->direction_input = iproc_gpio_direction_input;
702 	gc->direction_output = iproc_gpio_direction_output;
703 	gc->set = iproc_gpio_set;
704 	gc->get = iproc_gpio_get;
705 
706 	chip->pinmux_is_supported = of_property_read_bool(dev->of_node,
707 							"gpio-ranges");
708 
709 	ret = gpiochip_add(gc);
710 	if (ret < 0) {
711 		dev_err(dev, "unable to add GPIO chip\n");
712 		return ret;
713 	}
714 
715 	ret = iproc_gpio_register_pinconf(chip);
716 	if (ret) {
717 		dev_err(dev, "unable to register pinconf\n");
718 		goto err_rm_gpiochip;
719 	}
720 
721 	/* optional GPIO interrupt support */
722 	irq = platform_get_irq(pdev, 0);
723 	if (irq) {
724 		ret = gpiochip_irqchip_add(gc, &iproc_gpio_irq_chip, 0,
725 					   handle_simple_irq, IRQ_TYPE_NONE);
726 		if (ret) {
727 			dev_err(dev, "no GPIO irqchip\n");
728 			goto err_unregister_pinconf;
729 		}
730 
731 		gpiochip_set_chained_irqchip(gc, &iproc_gpio_irq_chip, irq,
732 					     iproc_gpio_irq_handler);
733 	}
734 
735 	return 0;
736 
737 err_unregister_pinconf:
738 	iproc_gpio_unregister_pinconf(chip);
739 
740 err_rm_gpiochip:
741 	gpiochip_remove(gc);
742 
743 	return ret;
744 }
745 
746 static struct platform_driver iproc_gpio_driver = {
747 	.driver = {
748 		.name = "iproc-gpio",
749 		.of_match_table = iproc_gpio_of_match,
750 	},
751 	.probe = iproc_gpio_probe,
752 };
753 
754 static int __init iproc_gpio_init(void)
755 {
756 	return platform_driver_probe(&iproc_gpio_driver, iproc_gpio_probe);
757 }
758 arch_initcall_sync(iproc_gpio_init);
759