xref: /linux/drivers/pinctrl/bcm/pinctrl-iproc-gpio.c (revision be709d48329a500621d2a05835283150ae137b45)
1 /*
2  * Copyright (C) 2014-2017 Broadcom
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 
14 /*
15  * This file contains the Broadcom Iproc GPIO driver that supports 3
16  * GPIO controllers on Iproc including the ASIU GPIO controller, the
17  * chipCommonG GPIO controller, and the always-on GPIO controller. Basic
18  * PINCONF such as bias pull up/down, and drive strength are also supported
19  * in this driver.
20  *
21  * It provides the functionality where pins from the GPIO can be
22  * individually muxed to GPIO function, if individual pad
23  * configuration is supported, through the interaction with respective
24  * SoCs IOMUX controller.
25  */
26 
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
29 #include <linux/interrupt.h>
30 #include <linux/io.h>
31 #include <linux/gpio/driver.h>
32 #include <linux/ioport.h>
33 #include <linux/of_device.h>
34 #include <linux/of_irq.h>
35 #include <linux/pinctrl/pinctrl.h>
36 #include <linux/pinctrl/pinconf.h>
37 #include <linux/pinctrl/pinconf-generic.h>
38 
39 #include "../pinctrl-utils.h"
40 
41 #define IPROC_GPIO_DATA_IN_OFFSET   0x00
42 #define IPROC_GPIO_DATA_OUT_OFFSET  0x04
43 #define IPROC_GPIO_OUT_EN_OFFSET    0x08
44 #define IPROC_GPIO_INT_TYPE_OFFSET  0x0c
45 #define IPROC_GPIO_INT_DE_OFFSET    0x10
46 #define IPROC_GPIO_INT_EDGE_OFFSET  0x14
47 #define IPROC_GPIO_INT_MSK_OFFSET   0x18
48 #define IPROC_GPIO_INT_STAT_OFFSET  0x1c
49 #define IPROC_GPIO_INT_MSTAT_OFFSET 0x20
50 #define IPROC_GPIO_INT_CLR_OFFSET   0x24
51 #define IPROC_GPIO_PAD_RES_OFFSET   0x34
52 #define IPROC_GPIO_RES_EN_OFFSET    0x38
53 
54 /* drive strength control for ASIU GPIO */
55 #define IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET 0x58
56 
57 /* drive strength control for CCM/CRMU (AON) GPIO */
58 #define IPROC_GPIO_DRV0_CTRL_OFFSET  0x00
59 
60 #define GPIO_BANK_SIZE 0x200
61 #define NGPIOS_PER_BANK 32
62 #define GPIO_BANK(pin) ((pin) / NGPIOS_PER_BANK)
63 
64 #define IPROC_GPIO_REG(pin, reg) (GPIO_BANK(pin) * GPIO_BANK_SIZE + (reg))
65 #define IPROC_GPIO_SHIFT(pin) ((pin) % NGPIOS_PER_BANK)
66 
67 #define GPIO_DRV_STRENGTH_BIT_SHIFT  20
68 #define GPIO_DRV_STRENGTH_BITS       3
69 #define GPIO_DRV_STRENGTH_BIT_MASK   ((1 << GPIO_DRV_STRENGTH_BITS) - 1)
70 
71 enum iproc_pinconf_param {
72 	IPROC_PINCONF_DRIVE_STRENGTH = 0,
73 	IPROC_PINCONF_BIAS_DISABLE,
74 	IPROC_PINCONF_BIAS_PULL_UP,
75 	IPROC_PINCONF_BIAS_PULL_DOWN,
76 	IPROC_PINCON_MAX,
77 };
78 
79 /*
80  * Iproc GPIO core
81  *
82  * @dev: pointer to device
83  * @base: I/O register base for Iproc GPIO controller
84  * @io_ctrl: I/O register base for certain type of Iproc GPIO controller that
85  * has the PINCONF support implemented outside of the GPIO block
86  * @lock: lock to protect access to I/O registers
87  * @gc: GPIO chip
88  * @num_banks: number of GPIO banks, each bank supports up to 32 GPIOs
89  * @pinmux_is_supported: flag to indicate this GPIO controller contains pins
90  * that can be individually muxed to GPIO
91  * @pinconf_disable: contains a list of PINCONF parameters that need to be
92  * disabled
93  * @nr_pinconf_disable: total number of PINCONF parameters that need to be
94  * disabled
95  * @pctl: pointer to pinctrl_dev
96  * @pctldesc: pinctrl descriptor
97  */
98 struct iproc_gpio {
99 	struct device *dev;
100 
101 	void __iomem *base;
102 	void __iomem *io_ctrl;
103 
104 	raw_spinlock_t lock;
105 
106 	struct gpio_chip gc;
107 	unsigned num_banks;
108 
109 	bool pinmux_is_supported;
110 
111 	enum pin_config_param *pinconf_disable;
112 	unsigned int nr_pinconf_disable;
113 
114 	struct pinctrl_dev *pctl;
115 	struct pinctrl_desc pctldesc;
116 };
117 
118 /*
119  * Mapping from PINCONF pins to GPIO pins is 1-to-1
120  */
121 static inline unsigned iproc_pin_to_gpio(unsigned pin)
122 {
123 	return pin;
124 }
125 
126 /**
127  *  iproc_set_bit - set or clear one bit (corresponding to the GPIO pin) in a
128  *  Iproc GPIO register
129  *
130  *  @iproc_gpio: Iproc GPIO device
131  *  @reg: register offset
132  *  @gpio: GPIO pin
133  *  @set: set or clear
134  */
135 static inline void iproc_set_bit(struct iproc_gpio *chip, unsigned int reg,
136 				  unsigned gpio, bool set)
137 {
138 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
139 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
140 	u32 val;
141 
142 	val = readl(chip->base + offset);
143 	if (set)
144 		val |= BIT(shift);
145 	else
146 		val &= ~BIT(shift);
147 	writel(val, chip->base + offset);
148 }
149 
150 static inline bool iproc_get_bit(struct iproc_gpio *chip, unsigned int reg,
151 				  unsigned gpio)
152 {
153 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
154 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
155 
156 	return !!(readl(chip->base + offset) & BIT(shift));
157 }
158 
159 static void iproc_gpio_irq_handler(struct irq_desc *desc)
160 {
161 	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
162 	struct iproc_gpio *chip = gpiochip_get_data(gc);
163 	struct irq_chip *irq_chip = irq_desc_get_chip(desc);
164 	int i, bit;
165 
166 	chained_irq_enter(irq_chip, desc);
167 
168 	/* go through the entire GPIO banks and handle all interrupts */
169 	for (i = 0; i < chip->num_banks; i++) {
170 		unsigned long val = readl(chip->base + (i * GPIO_BANK_SIZE) +
171 					  IPROC_GPIO_INT_MSTAT_OFFSET);
172 
173 		for_each_set_bit(bit, &val, NGPIOS_PER_BANK) {
174 			unsigned pin = NGPIOS_PER_BANK * i + bit;
175 			int child_irq = irq_find_mapping(gc->irq.domain, pin);
176 
177 			/*
178 			 * Clear the interrupt before invoking the
179 			 * handler, so we do not leave any window
180 			 */
181 			writel(BIT(bit), chip->base + (i * GPIO_BANK_SIZE) +
182 			       IPROC_GPIO_INT_CLR_OFFSET);
183 
184 			generic_handle_irq(child_irq);
185 		}
186 	}
187 
188 	chained_irq_exit(irq_chip, desc);
189 }
190 
191 
192 static void iproc_gpio_irq_ack(struct irq_data *d)
193 {
194 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
195 	struct iproc_gpio *chip = gpiochip_get_data(gc);
196 	unsigned gpio = d->hwirq;
197 	unsigned int offset = IPROC_GPIO_REG(gpio,
198 			IPROC_GPIO_INT_CLR_OFFSET);
199 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
200 	u32 val = BIT(shift);
201 
202 	writel(val, chip->base + offset);
203 }
204 
205 /**
206  *  iproc_gpio_irq_set_mask - mask/unmask a GPIO interrupt
207  *
208  *  @d: IRQ chip data
209  *  @unmask: mask/unmask GPIO interrupt
210  */
211 static void iproc_gpio_irq_set_mask(struct irq_data *d, bool unmask)
212 {
213 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
214 	struct iproc_gpio *chip = gpiochip_get_data(gc);
215 	unsigned gpio = d->hwirq;
216 
217 	iproc_set_bit(chip, IPROC_GPIO_INT_MSK_OFFSET, gpio, unmask);
218 }
219 
220 static void iproc_gpio_irq_mask(struct irq_data *d)
221 {
222 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
223 	struct iproc_gpio *chip = gpiochip_get_data(gc);
224 	unsigned long flags;
225 
226 	raw_spin_lock_irqsave(&chip->lock, flags);
227 	iproc_gpio_irq_set_mask(d, false);
228 	raw_spin_unlock_irqrestore(&chip->lock, flags);
229 }
230 
231 static void iproc_gpio_irq_unmask(struct irq_data *d)
232 {
233 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
234 	struct iproc_gpio *chip = gpiochip_get_data(gc);
235 	unsigned long flags;
236 
237 	raw_spin_lock_irqsave(&chip->lock, flags);
238 	iproc_gpio_irq_set_mask(d, true);
239 	raw_spin_unlock_irqrestore(&chip->lock, flags);
240 }
241 
242 static int iproc_gpio_irq_set_type(struct irq_data *d, unsigned int type)
243 {
244 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
245 	struct iproc_gpio *chip = gpiochip_get_data(gc);
246 	unsigned gpio = d->hwirq;
247 	bool level_triggered = false;
248 	bool dual_edge = false;
249 	bool rising_or_high = false;
250 	unsigned long flags;
251 
252 	switch (type & IRQ_TYPE_SENSE_MASK) {
253 	case IRQ_TYPE_EDGE_RISING:
254 		rising_or_high = true;
255 		break;
256 
257 	case IRQ_TYPE_EDGE_FALLING:
258 		break;
259 
260 	case IRQ_TYPE_EDGE_BOTH:
261 		dual_edge = true;
262 		break;
263 
264 	case IRQ_TYPE_LEVEL_HIGH:
265 		level_triggered = true;
266 		rising_or_high = true;
267 		break;
268 
269 	case IRQ_TYPE_LEVEL_LOW:
270 		level_triggered = true;
271 		break;
272 
273 	default:
274 		dev_err(chip->dev, "invalid GPIO IRQ type 0x%x\n",
275 			type);
276 		return -EINVAL;
277 	}
278 
279 	raw_spin_lock_irqsave(&chip->lock, flags);
280 	iproc_set_bit(chip, IPROC_GPIO_INT_TYPE_OFFSET, gpio,
281 		       level_triggered);
282 	iproc_set_bit(chip, IPROC_GPIO_INT_DE_OFFSET, gpio, dual_edge);
283 	iproc_set_bit(chip, IPROC_GPIO_INT_EDGE_OFFSET, gpio,
284 		       rising_or_high);
285 	raw_spin_unlock_irqrestore(&chip->lock, flags);
286 
287 	dev_dbg(chip->dev,
288 		"gpio:%u level_triggered:%d dual_edge:%d rising_or_high:%d\n",
289 		gpio, level_triggered, dual_edge, rising_or_high);
290 
291 	return 0;
292 }
293 
294 static struct irq_chip iproc_gpio_irq_chip = {
295 	.name = "bcm-iproc-gpio",
296 	.irq_ack = iproc_gpio_irq_ack,
297 	.irq_mask = iproc_gpio_irq_mask,
298 	.irq_unmask = iproc_gpio_irq_unmask,
299 	.irq_set_type = iproc_gpio_irq_set_type,
300 };
301 
302 /*
303  * Request the Iproc IOMUX pinmux controller to mux individual pins to GPIO
304  */
305 static int iproc_gpio_request(struct gpio_chip *gc, unsigned offset)
306 {
307 	struct iproc_gpio *chip = gpiochip_get_data(gc);
308 	unsigned gpio = gc->base + offset;
309 
310 	/* not all Iproc GPIO pins can be muxed individually */
311 	if (!chip->pinmux_is_supported)
312 		return 0;
313 
314 	return pinctrl_gpio_request(gpio);
315 }
316 
317 static void iproc_gpio_free(struct gpio_chip *gc, unsigned offset)
318 {
319 	struct iproc_gpio *chip = gpiochip_get_data(gc);
320 	unsigned gpio = gc->base + offset;
321 
322 	if (!chip->pinmux_is_supported)
323 		return;
324 
325 	pinctrl_gpio_free(gpio);
326 }
327 
328 static int iproc_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
329 {
330 	struct iproc_gpio *chip = gpiochip_get_data(gc);
331 	unsigned long flags;
332 
333 	raw_spin_lock_irqsave(&chip->lock, flags);
334 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, false);
335 	raw_spin_unlock_irqrestore(&chip->lock, flags);
336 
337 	dev_dbg(chip->dev, "gpio:%u set input\n", gpio);
338 
339 	return 0;
340 }
341 
342 static int iproc_gpio_direction_output(struct gpio_chip *gc, unsigned gpio,
343 					int val)
344 {
345 	struct iproc_gpio *chip = gpiochip_get_data(gc);
346 	unsigned long flags;
347 
348 	raw_spin_lock_irqsave(&chip->lock, flags);
349 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, true);
350 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
351 	raw_spin_unlock_irqrestore(&chip->lock, flags);
352 
353 	dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val);
354 
355 	return 0;
356 }
357 
358 static void iproc_gpio_set(struct gpio_chip *gc, unsigned gpio, int val)
359 {
360 	struct iproc_gpio *chip = gpiochip_get_data(gc);
361 	unsigned long flags;
362 
363 	raw_spin_lock_irqsave(&chip->lock, flags);
364 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
365 	raw_spin_unlock_irqrestore(&chip->lock, flags);
366 
367 	dev_dbg(chip->dev, "gpio:%u set, value:%d\n", gpio, val);
368 }
369 
370 static int iproc_gpio_get(struct gpio_chip *gc, unsigned gpio)
371 {
372 	struct iproc_gpio *chip = gpiochip_get_data(gc);
373 	unsigned int offset = IPROC_GPIO_REG(gpio,
374 					      IPROC_GPIO_DATA_IN_OFFSET);
375 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
376 
377 	return !!(readl(chip->base + offset) & BIT(shift));
378 }
379 
380 /*
381  * Mapping of the iProc PINCONF parameters to the generic pin configuration
382  * parameters
383  */
384 static const enum pin_config_param iproc_pinconf_disable_map[] = {
385 	[IPROC_PINCONF_DRIVE_STRENGTH] = PIN_CONFIG_DRIVE_STRENGTH,
386 	[IPROC_PINCONF_BIAS_DISABLE] = PIN_CONFIG_BIAS_DISABLE,
387 	[IPROC_PINCONF_BIAS_PULL_UP] = PIN_CONFIG_BIAS_PULL_UP,
388 	[IPROC_PINCONF_BIAS_PULL_DOWN] = PIN_CONFIG_BIAS_PULL_DOWN,
389 };
390 
391 static bool iproc_pinconf_param_is_disabled(struct iproc_gpio *chip,
392 					    enum pin_config_param param)
393 {
394 	unsigned int i;
395 
396 	if (!chip->nr_pinconf_disable)
397 		return false;
398 
399 	for (i = 0; i < chip->nr_pinconf_disable; i++)
400 		if (chip->pinconf_disable[i] == param)
401 			return true;
402 
403 	return false;
404 }
405 
406 static int iproc_pinconf_disable_map_create(struct iproc_gpio *chip,
407 					    unsigned long disable_mask)
408 {
409 	unsigned int map_size = ARRAY_SIZE(iproc_pinconf_disable_map);
410 	unsigned int bit, nbits = 0;
411 
412 	/* figure out total number of PINCONF parameters to disable */
413 	for_each_set_bit(bit, &disable_mask, map_size)
414 		nbits++;
415 
416 	if (!nbits)
417 		return 0;
418 
419 	/*
420 	 * Allocate an array to store PINCONF parameters that need to be
421 	 * disabled
422 	 */
423 	chip->pinconf_disable = devm_kcalloc(chip->dev, nbits,
424 					     sizeof(*chip->pinconf_disable),
425 					     GFP_KERNEL);
426 	if (!chip->pinconf_disable)
427 		return -ENOMEM;
428 
429 	chip->nr_pinconf_disable = nbits;
430 
431 	/* now store these parameters */
432 	nbits = 0;
433 	for_each_set_bit(bit, &disable_mask, map_size)
434 		chip->pinconf_disable[nbits++] = iproc_pinconf_disable_map[bit];
435 
436 	return 0;
437 }
438 
439 static int iproc_get_groups_count(struct pinctrl_dev *pctldev)
440 {
441 	return 1;
442 }
443 
444 /*
445  * Only one group: "gpio_grp", since this local pinctrl device only performs
446  * GPIO specific PINCONF configurations
447  */
448 static const char *iproc_get_group_name(struct pinctrl_dev *pctldev,
449 					 unsigned selector)
450 {
451 	return "gpio_grp";
452 }
453 
454 static const struct pinctrl_ops iproc_pctrl_ops = {
455 	.get_groups_count = iproc_get_groups_count,
456 	.get_group_name = iproc_get_group_name,
457 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
458 	.dt_free_map = pinctrl_utils_free_map,
459 };
460 
461 static int iproc_gpio_set_pull(struct iproc_gpio *chip, unsigned gpio,
462 				bool disable, bool pull_up)
463 {
464 	unsigned long flags;
465 
466 	raw_spin_lock_irqsave(&chip->lock, flags);
467 
468 	if (disable) {
469 		iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio, false);
470 	} else {
471 		iproc_set_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio,
472 			       pull_up);
473 		iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio, true);
474 	}
475 
476 	raw_spin_unlock_irqrestore(&chip->lock, flags);
477 
478 	dev_dbg(chip->dev, "gpio:%u set pullup:%d\n", gpio, pull_up);
479 
480 	return 0;
481 }
482 
483 static void iproc_gpio_get_pull(struct iproc_gpio *chip, unsigned gpio,
484 				 bool *disable, bool *pull_up)
485 {
486 	unsigned long flags;
487 
488 	raw_spin_lock_irqsave(&chip->lock, flags);
489 	*disable = !iproc_get_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio);
490 	*pull_up = iproc_get_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio);
491 	raw_spin_unlock_irqrestore(&chip->lock, flags);
492 }
493 
494 static int iproc_gpio_set_strength(struct iproc_gpio *chip, unsigned gpio,
495 				    unsigned strength)
496 {
497 	void __iomem *base;
498 	unsigned int i, offset, shift;
499 	u32 val;
500 	unsigned long flags;
501 
502 	/* make sure drive strength is supported */
503 	if (strength < 2 ||  strength > 16 || (strength % 2))
504 		return -ENOTSUPP;
505 
506 	if (chip->io_ctrl) {
507 		base = chip->io_ctrl;
508 		offset = IPROC_GPIO_DRV0_CTRL_OFFSET;
509 	} else {
510 		base = chip->base;
511 		offset = IPROC_GPIO_REG(gpio,
512 					 IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET);
513 	}
514 
515 	shift = IPROC_GPIO_SHIFT(gpio);
516 
517 	dev_dbg(chip->dev, "gpio:%u set drive strength:%d mA\n", gpio,
518 		strength);
519 
520 	raw_spin_lock_irqsave(&chip->lock, flags);
521 	strength = (strength / 2) - 1;
522 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
523 		val = readl(base + offset);
524 		val &= ~BIT(shift);
525 		val |= ((strength >> i) & 0x1) << shift;
526 		writel(val, base + offset);
527 		offset += 4;
528 	}
529 	raw_spin_unlock_irqrestore(&chip->lock, flags);
530 
531 	return 0;
532 }
533 
534 static int iproc_gpio_get_strength(struct iproc_gpio *chip, unsigned gpio,
535 				    u16 *strength)
536 {
537 	void __iomem *base;
538 	unsigned int i, offset, shift;
539 	u32 val;
540 	unsigned long flags;
541 
542 	if (chip->io_ctrl) {
543 		base = chip->io_ctrl;
544 		offset = IPROC_GPIO_DRV0_CTRL_OFFSET;
545 	} else {
546 		base = chip->base;
547 		offset = IPROC_GPIO_REG(gpio,
548 					 IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET);
549 	}
550 
551 	shift = IPROC_GPIO_SHIFT(gpio);
552 
553 	raw_spin_lock_irqsave(&chip->lock, flags);
554 	*strength = 0;
555 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
556 		val = readl(base + offset) & BIT(shift);
557 		val >>= shift;
558 		*strength += (val << i);
559 		offset += 4;
560 	}
561 
562 	/* convert to mA */
563 	*strength = (*strength + 1) * 2;
564 	raw_spin_unlock_irqrestore(&chip->lock, flags);
565 
566 	return 0;
567 }
568 
569 static int iproc_pin_config_get(struct pinctrl_dev *pctldev, unsigned pin,
570 				 unsigned long *config)
571 {
572 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
573 	enum pin_config_param param = pinconf_to_config_param(*config);
574 	unsigned gpio = iproc_pin_to_gpio(pin);
575 	u16 arg;
576 	bool disable, pull_up;
577 	int ret;
578 
579 	if (iproc_pinconf_param_is_disabled(chip, param))
580 		return -ENOTSUPP;
581 
582 	switch (param) {
583 	case PIN_CONFIG_BIAS_DISABLE:
584 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
585 		if (disable)
586 			return 0;
587 		else
588 			return -EINVAL;
589 
590 	case PIN_CONFIG_BIAS_PULL_UP:
591 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
592 		if (!disable && pull_up)
593 			return 0;
594 		else
595 			return -EINVAL;
596 
597 	case PIN_CONFIG_BIAS_PULL_DOWN:
598 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
599 		if (!disable && !pull_up)
600 			return 0;
601 		else
602 			return -EINVAL;
603 
604 	case PIN_CONFIG_DRIVE_STRENGTH:
605 		ret = iproc_gpio_get_strength(chip, gpio, &arg);
606 		if (ret)
607 			return ret;
608 		*config = pinconf_to_config_packed(param, arg);
609 
610 		return 0;
611 
612 	default:
613 		return -ENOTSUPP;
614 	}
615 
616 	return -ENOTSUPP;
617 }
618 
619 static int iproc_pin_config_set(struct pinctrl_dev *pctldev, unsigned pin,
620 				 unsigned long *configs, unsigned num_configs)
621 {
622 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
623 	enum pin_config_param param;
624 	u32 arg;
625 	unsigned i, gpio = iproc_pin_to_gpio(pin);
626 	int ret = -ENOTSUPP;
627 
628 	for (i = 0; i < num_configs; i++) {
629 		param = pinconf_to_config_param(configs[i]);
630 
631 		if (iproc_pinconf_param_is_disabled(chip, param))
632 			return -ENOTSUPP;
633 
634 		arg = pinconf_to_config_argument(configs[i]);
635 
636 		switch (param) {
637 		case PIN_CONFIG_BIAS_DISABLE:
638 			ret = iproc_gpio_set_pull(chip, gpio, true, false);
639 			if (ret < 0)
640 				goto out;
641 			break;
642 
643 		case PIN_CONFIG_BIAS_PULL_UP:
644 			ret = iproc_gpio_set_pull(chip, gpio, false, true);
645 			if (ret < 0)
646 				goto out;
647 			break;
648 
649 		case PIN_CONFIG_BIAS_PULL_DOWN:
650 			ret = iproc_gpio_set_pull(chip, gpio, false, false);
651 			if (ret < 0)
652 				goto out;
653 			break;
654 
655 		case PIN_CONFIG_DRIVE_STRENGTH:
656 			ret = iproc_gpio_set_strength(chip, gpio, arg);
657 			if (ret < 0)
658 				goto out;
659 			break;
660 
661 		default:
662 			dev_err(chip->dev, "invalid configuration\n");
663 			return -ENOTSUPP;
664 		}
665 	} /* for each config */
666 
667 out:
668 	return ret;
669 }
670 
671 static const struct pinconf_ops iproc_pconf_ops = {
672 	.is_generic = true,
673 	.pin_config_get = iproc_pin_config_get,
674 	.pin_config_set = iproc_pin_config_set,
675 };
676 
677 /*
678  * Iproc GPIO controller supports some PINCONF related configurations such as
679  * pull up, pull down, and drive strength, when the pin is configured to GPIO
680  *
681  * Here a local pinctrl device is created with simple 1-to-1 pin mapping to the
682  * local GPIO pins
683  */
684 static int iproc_gpio_register_pinconf(struct iproc_gpio *chip)
685 {
686 	struct pinctrl_desc *pctldesc = &chip->pctldesc;
687 	struct pinctrl_pin_desc *pins;
688 	struct gpio_chip *gc = &chip->gc;
689 	int i;
690 
691 	pins = devm_kcalloc(chip->dev, gc->ngpio, sizeof(*pins), GFP_KERNEL);
692 	if (!pins)
693 		return -ENOMEM;
694 
695 	for (i = 0; i < gc->ngpio; i++) {
696 		pins[i].number = i;
697 		pins[i].name = devm_kasprintf(chip->dev, GFP_KERNEL,
698 					      "gpio-%d", i);
699 		if (!pins[i].name)
700 			return -ENOMEM;
701 	}
702 
703 	pctldesc->name = dev_name(chip->dev);
704 	pctldesc->pctlops = &iproc_pctrl_ops;
705 	pctldesc->pins = pins;
706 	pctldesc->npins = gc->ngpio;
707 	pctldesc->confops = &iproc_pconf_ops;
708 
709 	chip->pctl = devm_pinctrl_register(chip->dev, pctldesc, chip);
710 	if (IS_ERR(chip->pctl)) {
711 		dev_err(chip->dev, "unable to register pinctrl device\n");
712 		return PTR_ERR(chip->pctl);
713 	}
714 
715 	return 0;
716 }
717 
718 static const struct of_device_id iproc_gpio_of_match[] = {
719 	{ .compatible = "brcm,iproc-gpio" },
720 	{ .compatible = "brcm,cygnus-ccm-gpio" },
721 	{ .compatible = "brcm,cygnus-asiu-gpio" },
722 	{ .compatible = "brcm,cygnus-crmu-gpio" },
723 	{ .compatible = "brcm,iproc-nsp-gpio" },
724 	{ .compatible = "brcm,iproc-stingray-gpio" },
725 	{ /* sentinel */ }
726 };
727 
728 static int iproc_gpio_probe(struct platform_device *pdev)
729 {
730 	struct device *dev = &pdev->dev;
731 	struct resource *res;
732 	struct iproc_gpio *chip;
733 	struct gpio_chip *gc;
734 	u32 ngpios, pinconf_disable_mask = 0;
735 	int irq, ret;
736 	bool no_pinconf = false;
737 
738 	/* NSP does not support drive strength config */
739 	if (of_device_is_compatible(dev->of_node, "brcm,iproc-nsp-gpio"))
740 		pinconf_disable_mask = BIT(IPROC_PINCONF_DRIVE_STRENGTH);
741 	/* Stingray does not support pinconf in this controller */
742 	else if (of_device_is_compatible(dev->of_node,
743 					 "brcm,iproc-stingray-gpio"))
744 		no_pinconf = true;
745 
746 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
747 	if (!chip)
748 		return -ENOMEM;
749 
750 	chip->dev = dev;
751 	platform_set_drvdata(pdev, chip);
752 
753 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
754 	chip->base = devm_ioremap_resource(dev, res);
755 	if (IS_ERR(chip->base)) {
756 		dev_err(dev, "unable to map I/O memory\n");
757 		return PTR_ERR(chip->base);
758 	}
759 
760 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
761 	if (res) {
762 		chip->io_ctrl = devm_ioremap_resource(dev, res);
763 		if (IS_ERR(chip->io_ctrl)) {
764 			dev_err(dev, "unable to map I/O memory\n");
765 			return PTR_ERR(chip->io_ctrl);
766 		}
767 	}
768 
769 	if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) {
770 		dev_err(&pdev->dev, "missing ngpios DT property\n");
771 		return -ENODEV;
772 	}
773 
774 	raw_spin_lock_init(&chip->lock);
775 
776 	gc = &chip->gc;
777 	gc->base = -1;
778 	gc->ngpio = ngpios;
779 	chip->num_banks = (ngpios + NGPIOS_PER_BANK - 1) / NGPIOS_PER_BANK;
780 	gc->label = dev_name(dev);
781 	gc->parent = dev;
782 	gc->of_node = dev->of_node;
783 	gc->request = iproc_gpio_request;
784 	gc->free = iproc_gpio_free;
785 	gc->direction_input = iproc_gpio_direction_input;
786 	gc->direction_output = iproc_gpio_direction_output;
787 	gc->set = iproc_gpio_set;
788 	gc->get = iproc_gpio_get;
789 
790 	chip->pinmux_is_supported = of_property_read_bool(dev->of_node,
791 							"gpio-ranges");
792 
793 	ret = gpiochip_add_data(gc, chip);
794 	if (ret < 0) {
795 		dev_err(dev, "unable to add GPIO chip\n");
796 		return ret;
797 	}
798 
799 	if (!no_pinconf) {
800 		ret = iproc_gpio_register_pinconf(chip);
801 		if (ret) {
802 			dev_err(dev, "unable to register pinconf\n");
803 			goto err_rm_gpiochip;
804 		}
805 
806 		if (pinconf_disable_mask) {
807 			ret = iproc_pinconf_disable_map_create(chip,
808 							 pinconf_disable_mask);
809 			if (ret) {
810 				dev_err(dev,
811 					"unable to create pinconf disable map\n");
812 				goto err_rm_gpiochip;
813 			}
814 		}
815 	}
816 
817 	/* optional GPIO interrupt support */
818 	irq = platform_get_irq(pdev, 0);
819 	if (irq) {
820 		ret = gpiochip_irqchip_add(gc, &iproc_gpio_irq_chip, 0,
821 					   handle_simple_irq, IRQ_TYPE_NONE);
822 		if (ret) {
823 			dev_err(dev, "no GPIO irqchip\n");
824 			goto err_rm_gpiochip;
825 		}
826 
827 		gpiochip_set_chained_irqchip(gc, &iproc_gpio_irq_chip, irq,
828 					     iproc_gpio_irq_handler);
829 	}
830 
831 	return 0;
832 
833 err_rm_gpiochip:
834 	gpiochip_remove(gc);
835 
836 	return ret;
837 }
838 
839 static struct platform_driver iproc_gpio_driver = {
840 	.driver = {
841 		.name = "iproc-gpio",
842 		.of_match_table = iproc_gpio_of_match,
843 	},
844 	.probe = iproc_gpio_probe,
845 };
846 
847 static int __init iproc_gpio_init(void)
848 {
849 	return platform_driver_register(&iproc_gpio_driver);
850 }
851 arch_initcall_sync(iproc_gpio_init);
852