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 /* pinconf for CCM GPIO */
58 #define IPROC_GPIO_PULL_DN_OFFSET   0x10
59 #define IPROC_GPIO_PULL_UP_OFFSET   0x14
60 
61 /* pinconf for CRMU(aon) GPIO and CCM GPIO*/
62 #define IPROC_GPIO_DRV_CTRL_OFFSET  0x00
63 
64 #define GPIO_BANK_SIZE 0x200
65 #define NGPIOS_PER_BANK 32
66 #define GPIO_BANK(pin) ((pin) / NGPIOS_PER_BANK)
67 
68 #define IPROC_GPIO_REG(pin, reg) (GPIO_BANK(pin) * GPIO_BANK_SIZE + (reg))
69 #define IPROC_GPIO_SHIFT(pin) ((pin) % NGPIOS_PER_BANK)
70 
71 #define GPIO_DRV_STRENGTH_BIT_SHIFT  20
72 #define GPIO_DRV_STRENGTH_BITS       3
73 #define GPIO_DRV_STRENGTH_BIT_MASK   ((1 << GPIO_DRV_STRENGTH_BITS) - 1)
74 
75 enum iproc_pinconf_param {
76 	IPROC_PINCONF_DRIVE_STRENGTH = 0,
77 	IPROC_PINCONF_BIAS_DISABLE,
78 	IPROC_PINCONF_BIAS_PULL_UP,
79 	IPROC_PINCONF_BIAS_PULL_DOWN,
80 	IPROC_PINCON_MAX,
81 };
82 
83 enum iproc_pinconf_ctrl_type {
84 	IOCTRL_TYPE_AON = 1,
85 	IOCTRL_TYPE_CDRU,
86 	IOCTRL_TYPE_INVALID,
87 };
88 
89 /*
90  * Iproc GPIO core
91  *
92  * @dev: pointer to device
93  * @base: I/O register base for Iproc GPIO controller
94  * @io_ctrl: I/O register base for certain type of Iproc GPIO controller that
95  * has the PINCONF support implemented outside of the GPIO block
96  * @lock: lock to protect access to I/O registers
97  * @gc: GPIO chip
98  * @num_banks: number of GPIO banks, each bank supports up to 32 GPIOs
99  * @pinmux_is_supported: flag to indicate this GPIO controller contains pins
100  * that can be individually muxed to GPIO
101  * @pinconf_disable: contains a list of PINCONF parameters that need to be
102  * disabled
103  * @nr_pinconf_disable: total number of PINCONF parameters that need to be
104  * disabled
105  * @pctl: pointer to pinctrl_dev
106  * @pctldesc: pinctrl descriptor
107  */
108 struct iproc_gpio {
109 	struct device *dev;
110 
111 	void __iomem *base;
112 	void __iomem *io_ctrl;
113 	enum iproc_pinconf_ctrl_type io_ctrl_type;
114 
115 	raw_spinlock_t lock;
116 
117 	struct irq_chip irqchip;
118 	struct gpio_chip gc;
119 	unsigned num_banks;
120 
121 	bool pinmux_is_supported;
122 
123 	enum pin_config_param *pinconf_disable;
124 	unsigned int nr_pinconf_disable;
125 
126 	struct pinctrl_dev *pctl;
127 	struct pinctrl_desc pctldesc;
128 };
129 
130 /*
131  * Mapping from PINCONF pins to GPIO pins is 1-to-1
132  */
133 static inline unsigned iproc_pin_to_gpio(unsigned pin)
134 {
135 	return pin;
136 }
137 
138 /**
139  *  iproc_set_bit - set or clear one bit (corresponding to the GPIO pin) in a
140  *  Iproc GPIO register
141  *
142  *  @iproc_gpio: Iproc GPIO device
143  *  @reg: register offset
144  *  @gpio: GPIO pin
145  *  @set: set or clear
146  */
147 static inline void iproc_set_bit(struct iproc_gpio *chip, unsigned int reg,
148 				  unsigned gpio, bool set)
149 {
150 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
151 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
152 	u32 val;
153 
154 	val = readl(chip->base + offset);
155 	if (set)
156 		val |= BIT(shift);
157 	else
158 		val &= ~BIT(shift);
159 	writel(val, chip->base + offset);
160 }
161 
162 static inline bool iproc_get_bit(struct iproc_gpio *chip, unsigned int reg,
163 				  unsigned gpio)
164 {
165 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
166 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
167 
168 	return !!(readl(chip->base + offset) & BIT(shift));
169 }
170 
171 static void iproc_gpio_irq_handler(struct irq_desc *desc)
172 {
173 	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
174 	struct iproc_gpio *chip = gpiochip_get_data(gc);
175 	struct irq_chip *irq_chip = irq_desc_get_chip(desc);
176 	int i, bit;
177 
178 	chained_irq_enter(irq_chip, desc);
179 
180 	/* go through the entire GPIO banks and handle all interrupts */
181 	for (i = 0; i < chip->num_banks; i++) {
182 		unsigned long val = readl(chip->base + (i * GPIO_BANK_SIZE) +
183 					  IPROC_GPIO_INT_MSTAT_OFFSET);
184 
185 		for_each_set_bit(bit, &val, NGPIOS_PER_BANK) {
186 			unsigned pin = NGPIOS_PER_BANK * i + bit;
187 			int child_irq = irq_find_mapping(gc->irq.domain, pin);
188 
189 			/*
190 			 * Clear the interrupt before invoking the
191 			 * handler, so we do not leave any window
192 			 */
193 			writel(BIT(bit), chip->base + (i * GPIO_BANK_SIZE) +
194 			       IPROC_GPIO_INT_CLR_OFFSET);
195 
196 			generic_handle_irq(child_irq);
197 		}
198 	}
199 
200 	chained_irq_exit(irq_chip, desc);
201 }
202 
203 
204 static void iproc_gpio_irq_ack(struct irq_data *d)
205 {
206 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
207 	struct iproc_gpio *chip = gpiochip_get_data(gc);
208 	unsigned gpio = d->hwirq;
209 	unsigned int offset = IPROC_GPIO_REG(gpio,
210 			IPROC_GPIO_INT_CLR_OFFSET);
211 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
212 	u32 val = BIT(shift);
213 
214 	writel(val, chip->base + offset);
215 }
216 
217 /**
218  *  iproc_gpio_irq_set_mask - mask/unmask a GPIO interrupt
219  *
220  *  @d: IRQ chip data
221  *  @unmask: mask/unmask GPIO interrupt
222  */
223 static void iproc_gpio_irq_set_mask(struct irq_data *d, bool unmask)
224 {
225 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
226 	struct iproc_gpio *chip = gpiochip_get_data(gc);
227 	unsigned gpio = d->hwirq;
228 
229 	iproc_set_bit(chip, IPROC_GPIO_INT_MSK_OFFSET, gpio, unmask);
230 }
231 
232 static void iproc_gpio_irq_mask(struct irq_data *d)
233 {
234 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
235 	struct iproc_gpio *chip = gpiochip_get_data(gc);
236 	unsigned long flags;
237 
238 	raw_spin_lock_irqsave(&chip->lock, flags);
239 	iproc_gpio_irq_set_mask(d, false);
240 	raw_spin_unlock_irqrestore(&chip->lock, flags);
241 }
242 
243 static void iproc_gpio_irq_unmask(struct irq_data *d)
244 {
245 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
246 	struct iproc_gpio *chip = gpiochip_get_data(gc);
247 	unsigned long flags;
248 
249 	raw_spin_lock_irqsave(&chip->lock, flags);
250 	iproc_gpio_irq_set_mask(d, true);
251 	raw_spin_unlock_irqrestore(&chip->lock, flags);
252 }
253 
254 static int iproc_gpio_irq_set_type(struct irq_data *d, unsigned int type)
255 {
256 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
257 	struct iproc_gpio *chip = gpiochip_get_data(gc);
258 	unsigned gpio = d->hwirq;
259 	bool level_triggered = false;
260 	bool dual_edge = false;
261 	bool rising_or_high = false;
262 	unsigned long flags;
263 
264 	switch (type & IRQ_TYPE_SENSE_MASK) {
265 	case IRQ_TYPE_EDGE_RISING:
266 		rising_or_high = true;
267 		break;
268 
269 	case IRQ_TYPE_EDGE_FALLING:
270 		break;
271 
272 	case IRQ_TYPE_EDGE_BOTH:
273 		dual_edge = true;
274 		break;
275 
276 	case IRQ_TYPE_LEVEL_HIGH:
277 		level_triggered = true;
278 		rising_or_high = true;
279 		break;
280 
281 	case IRQ_TYPE_LEVEL_LOW:
282 		level_triggered = true;
283 		break;
284 
285 	default:
286 		dev_err(chip->dev, "invalid GPIO IRQ type 0x%x\n",
287 			type);
288 		return -EINVAL;
289 	}
290 
291 	raw_spin_lock_irqsave(&chip->lock, flags);
292 	iproc_set_bit(chip, IPROC_GPIO_INT_TYPE_OFFSET, gpio,
293 		       level_triggered);
294 	iproc_set_bit(chip, IPROC_GPIO_INT_DE_OFFSET, gpio, dual_edge);
295 	iproc_set_bit(chip, IPROC_GPIO_INT_EDGE_OFFSET, gpio,
296 		       rising_or_high);
297 	raw_spin_unlock_irqrestore(&chip->lock, flags);
298 
299 	dev_dbg(chip->dev,
300 		"gpio:%u level_triggered:%d dual_edge:%d rising_or_high:%d\n",
301 		gpio, level_triggered, dual_edge, rising_or_high);
302 
303 	return 0;
304 }
305 
306 /*
307  * Request the Iproc IOMUX pinmux controller to mux individual pins to GPIO
308  */
309 static int iproc_gpio_request(struct gpio_chip *gc, unsigned offset)
310 {
311 	struct iproc_gpio *chip = gpiochip_get_data(gc);
312 	unsigned gpio = gc->base + offset;
313 
314 	/* not all Iproc GPIO pins can be muxed individually */
315 	if (!chip->pinmux_is_supported)
316 		return 0;
317 
318 	return pinctrl_gpio_request(gpio);
319 }
320 
321 static void iproc_gpio_free(struct gpio_chip *gc, unsigned offset)
322 {
323 	struct iproc_gpio *chip = gpiochip_get_data(gc);
324 	unsigned gpio = gc->base + offset;
325 
326 	if (!chip->pinmux_is_supported)
327 		return;
328 
329 	pinctrl_gpio_free(gpio);
330 }
331 
332 static int iproc_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
333 {
334 	struct iproc_gpio *chip = gpiochip_get_data(gc);
335 	unsigned long flags;
336 
337 	raw_spin_lock_irqsave(&chip->lock, flags);
338 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, false);
339 	raw_spin_unlock_irqrestore(&chip->lock, flags);
340 
341 	dev_dbg(chip->dev, "gpio:%u set input\n", gpio);
342 
343 	return 0;
344 }
345 
346 static int iproc_gpio_direction_output(struct gpio_chip *gc, unsigned gpio,
347 					int val)
348 {
349 	struct iproc_gpio *chip = gpiochip_get_data(gc);
350 	unsigned long flags;
351 
352 	raw_spin_lock_irqsave(&chip->lock, flags);
353 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, true);
354 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
355 	raw_spin_unlock_irqrestore(&chip->lock, flags);
356 
357 	dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val);
358 
359 	return 0;
360 }
361 
362 static int iproc_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio)
363 {
364 	struct iproc_gpio *chip = gpiochip_get_data(gc);
365 	unsigned int offset = IPROC_GPIO_REG(gpio, IPROC_GPIO_OUT_EN_OFFSET);
366 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
367 
368 	return !(readl(chip->base + offset) & BIT(shift));
369 }
370 
371 static void iproc_gpio_set(struct gpio_chip *gc, unsigned gpio, int val)
372 {
373 	struct iproc_gpio *chip = gpiochip_get_data(gc);
374 	unsigned long flags;
375 
376 	raw_spin_lock_irqsave(&chip->lock, flags);
377 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
378 	raw_spin_unlock_irqrestore(&chip->lock, flags);
379 
380 	dev_dbg(chip->dev, "gpio:%u set, value:%d\n", gpio, val);
381 }
382 
383 static int iproc_gpio_get(struct gpio_chip *gc, unsigned gpio)
384 {
385 	struct iproc_gpio *chip = gpiochip_get_data(gc);
386 	unsigned int offset = IPROC_GPIO_REG(gpio,
387 					      IPROC_GPIO_DATA_IN_OFFSET);
388 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
389 
390 	return !!(readl(chip->base + offset) & BIT(shift));
391 }
392 
393 /*
394  * Mapping of the iProc PINCONF parameters to the generic pin configuration
395  * parameters
396  */
397 static const enum pin_config_param iproc_pinconf_disable_map[] = {
398 	[IPROC_PINCONF_DRIVE_STRENGTH] = PIN_CONFIG_DRIVE_STRENGTH,
399 	[IPROC_PINCONF_BIAS_DISABLE] = PIN_CONFIG_BIAS_DISABLE,
400 	[IPROC_PINCONF_BIAS_PULL_UP] = PIN_CONFIG_BIAS_PULL_UP,
401 	[IPROC_PINCONF_BIAS_PULL_DOWN] = PIN_CONFIG_BIAS_PULL_DOWN,
402 };
403 
404 static bool iproc_pinconf_param_is_disabled(struct iproc_gpio *chip,
405 					    enum pin_config_param param)
406 {
407 	unsigned int i;
408 
409 	if (!chip->nr_pinconf_disable)
410 		return false;
411 
412 	for (i = 0; i < chip->nr_pinconf_disable; i++)
413 		if (chip->pinconf_disable[i] == param)
414 			return true;
415 
416 	return false;
417 }
418 
419 static int iproc_pinconf_disable_map_create(struct iproc_gpio *chip,
420 					    unsigned long disable_mask)
421 {
422 	unsigned int map_size = ARRAY_SIZE(iproc_pinconf_disable_map);
423 	unsigned int bit, nbits = 0;
424 
425 	/* figure out total number of PINCONF parameters to disable */
426 	for_each_set_bit(bit, &disable_mask, map_size)
427 		nbits++;
428 
429 	if (!nbits)
430 		return 0;
431 
432 	/*
433 	 * Allocate an array to store PINCONF parameters that need to be
434 	 * disabled
435 	 */
436 	chip->pinconf_disable = devm_kcalloc(chip->dev, nbits,
437 					     sizeof(*chip->pinconf_disable),
438 					     GFP_KERNEL);
439 	if (!chip->pinconf_disable)
440 		return -ENOMEM;
441 
442 	chip->nr_pinconf_disable = nbits;
443 
444 	/* now store these parameters */
445 	nbits = 0;
446 	for_each_set_bit(bit, &disable_mask, map_size)
447 		chip->pinconf_disable[nbits++] = iproc_pinconf_disable_map[bit];
448 
449 	return 0;
450 }
451 
452 static int iproc_get_groups_count(struct pinctrl_dev *pctldev)
453 {
454 	return 1;
455 }
456 
457 /*
458  * Only one group: "gpio_grp", since this local pinctrl device only performs
459  * GPIO specific PINCONF configurations
460  */
461 static const char *iproc_get_group_name(struct pinctrl_dev *pctldev,
462 					 unsigned selector)
463 {
464 	return "gpio_grp";
465 }
466 
467 static const struct pinctrl_ops iproc_pctrl_ops = {
468 	.get_groups_count = iproc_get_groups_count,
469 	.get_group_name = iproc_get_group_name,
470 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
471 	.dt_free_map = pinctrl_utils_free_map,
472 };
473 
474 static int iproc_gpio_set_pull(struct iproc_gpio *chip, unsigned gpio,
475 				bool disable, bool pull_up)
476 {
477 	void __iomem *base;
478 	unsigned long flags;
479 	unsigned int shift;
480 	u32 val_1, val_2;
481 
482 	raw_spin_lock_irqsave(&chip->lock, flags);
483 	if (chip->io_ctrl_type == IOCTRL_TYPE_CDRU) {
484 		base = chip->io_ctrl;
485 		shift = IPROC_GPIO_SHIFT(gpio);
486 
487 		val_1 = readl(base + IPROC_GPIO_PULL_UP_OFFSET);
488 		val_2 = readl(base + IPROC_GPIO_PULL_DN_OFFSET);
489 		if (disable) {
490 			/* no pull-up or pull-down */
491 			val_1 &= ~BIT(shift);
492 			val_2 &= ~BIT(shift);
493 		} else if (pull_up) {
494 			val_1 |= BIT(shift);
495 			val_2 &= ~BIT(shift);
496 		} else {
497 			val_1 &= ~BIT(shift);
498 			val_2 |= BIT(shift);
499 		}
500 		writel(val_1, base + IPROC_GPIO_PULL_UP_OFFSET);
501 		writel(val_2, base + IPROC_GPIO_PULL_DN_OFFSET);
502 	} else {
503 		if (disable) {
504 			iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio,
505 				      false);
506 		} else {
507 			iproc_set_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio,
508 				      pull_up);
509 			iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio,
510 				      true);
511 		}
512 	}
513 
514 	raw_spin_unlock_irqrestore(&chip->lock, flags);
515 	dev_dbg(chip->dev, "gpio:%u set pullup:%d\n", gpio, pull_up);
516 
517 	return 0;
518 }
519 
520 static void iproc_gpio_get_pull(struct iproc_gpio *chip, unsigned gpio,
521 				 bool *disable, bool *pull_up)
522 {
523 	void __iomem *base;
524 	unsigned long flags;
525 	unsigned int shift;
526 	u32 val_1, val_2;
527 
528 	raw_spin_lock_irqsave(&chip->lock, flags);
529 	if (chip->io_ctrl_type == IOCTRL_TYPE_CDRU) {
530 		base = chip->io_ctrl;
531 		shift = IPROC_GPIO_SHIFT(gpio);
532 
533 		val_1 = readl(base + IPROC_GPIO_PULL_UP_OFFSET) & BIT(shift);
534 		val_2 = readl(base + IPROC_GPIO_PULL_DN_OFFSET) & BIT(shift);
535 
536 		*pull_up = val_1 ? true : false;
537 		*disable = (val_1 | val_2) ? false : true;
538 
539 	} else {
540 		*disable = !iproc_get_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio);
541 		*pull_up = iproc_get_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio);
542 	}
543 	raw_spin_unlock_irqrestore(&chip->lock, flags);
544 }
545 
546 #define DRV_STRENGTH_OFFSET(gpio, bit, type)  ((type) == IOCTRL_TYPE_AON ? \
547 	((2 - (bit)) * 4 + IPROC_GPIO_DRV_CTRL_OFFSET) : \
548 	((type) == IOCTRL_TYPE_CDRU) ? \
549 	((bit) * 4 + IPROC_GPIO_DRV_CTRL_OFFSET) : \
550 	((bit) * 4 + IPROC_GPIO_REG(gpio, IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET)))
551 
552 static int iproc_gpio_set_strength(struct iproc_gpio *chip, unsigned gpio,
553 				    unsigned strength)
554 {
555 	void __iomem *base;
556 	unsigned int i, offset, shift;
557 	u32 val;
558 	unsigned long flags;
559 
560 	/* make sure drive strength is supported */
561 	if (strength < 2 ||  strength > 16 || (strength % 2))
562 		return -ENOTSUPP;
563 
564 	if (chip->io_ctrl) {
565 		base = chip->io_ctrl;
566 	} else {
567 		base = chip->base;
568 	}
569 
570 	shift = IPROC_GPIO_SHIFT(gpio);
571 
572 	dev_dbg(chip->dev, "gpio:%u set drive strength:%d mA\n", gpio,
573 		strength);
574 
575 	raw_spin_lock_irqsave(&chip->lock, flags);
576 	strength = (strength / 2) - 1;
577 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
578 		offset = DRV_STRENGTH_OFFSET(gpio, i, chip->io_ctrl_type);
579 		val = readl(base + offset);
580 		val &= ~BIT(shift);
581 		val |= ((strength >> i) & 0x1) << shift;
582 		writel(val, base + offset);
583 	}
584 	raw_spin_unlock_irqrestore(&chip->lock, flags);
585 
586 	return 0;
587 }
588 
589 static int iproc_gpio_get_strength(struct iproc_gpio *chip, unsigned gpio,
590 				    u16 *strength)
591 {
592 	void __iomem *base;
593 	unsigned int i, offset, shift;
594 	u32 val;
595 	unsigned long flags;
596 
597 	if (chip->io_ctrl) {
598 		base = chip->io_ctrl;
599 	} else {
600 		base = chip->base;
601 	}
602 
603 	shift = IPROC_GPIO_SHIFT(gpio);
604 
605 	raw_spin_lock_irqsave(&chip->lock, flags);
606 	*strength = 0;
607 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
608 		offset = DRV_STRENGTH_OFFSET(gpio, i, chip->io_ctrl_type);
609 		val = readl(base + offset) & BIT(shift);
610 		val >>= shift;
611 		*strength += (val << i);
612 	}
613 
614 	/* convert to mA */
615 	*strength = (*strength + 1) * 2;
616 	raw_spin_unlock_irqrestore(&chip->lock, flags);
617 
618 	return 0;
619 }
620 
621 static int iproc_pin_config_get(struct pinctrl_dev *pctldev, unsigned pin,
622 				 unsigned long *config)
623 {
624 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
625 	enum pin_config_param param = pinconf_to_config_param(*config);
626 	unsigned gpio = iproc_pin_to_gpio(pin);
627 	u16 arg;
628 	bool disable, pull_up;
629 	int ret;
630 
631 	if (iproc_pinconf_param_is_disabled(chip, param))
632 		return -ENOTSUPP;
633 
634 	switch (param) {
635 	case PIN_CONFIG_BIAS_DISABLE:
636 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
637 		if (disable)
638 			return 0;
639 		else
640 			return -EINVAL;
641 
642 	case PIN_CONFIG_BIAS_PULL_UP:
643 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
644 		if (!disable && pull_up)
645 			return 0;
646 		else
647 			return -EINVAL;
648 
649 	case PIN_CONFIG_BIAS_PULL_DOWN:
650 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
651 		if (!disable && !pull_up)
652 			return 0;
653 		else
654 			return -EINVAL;
655 
656 	case PIN_CONFIG_DRIVE_STRENGTH:
657 		ret = iproc_gpio_get_strength(chip, gpio, &arg);
658 		if (ret)
659 			return ret;
660 		*config = pinconf_to_config_packed(param, arg);
661 
662 		return 0;
663 
664 	default:
665 		return -ENOTSUPP;
666 	}
667 
668 	return -ENOTSUPP;
669 }
670 
671 static int iproc_pin_config_set(struct pinctrl_dev *pctldev, unsigned pin,
672 				 unsigned long *configs, unsigned num_configs)
673 {
674 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
675 	enum pin_config_param param;
676 	u32 arg;
677 	unsigned i, gpio = iproc_pin_to_gpio(pin);
678 	int ret = -ENOTSUPP;
679 
680 	for (i = 0; i < num_configs; i++) {
681 		param = pinconf_to_config_param(configs[i]);
682 
683 		if (iproc_pinconf_param_is_disabled(chip, param))
684 			return -ENOTSUPP;
685 
686 		arg = pinconf_to_config_argument(configs[i]);
687 
688 		switch (param) {
689 		case PIN_CONFIG_BIAS_DISABLE:
690 			ret = iproc_gpio_set_pull(chip, gpio, true, false);
691 			if (ret < 0)
692 				goto out;
693 			break;
694 
695 		case PIN_CONFIG_BIAS_PULL_UP:
696 			ret = iproc_gpio_set_pull(chip, gpio, false, true);
697 			if (ret < 0)
698 				goto out;
699 			break;
700 
701 		case PIN_CONFIG_BIAS_PULL_DOWN:
702 			ret = iproc_gpio_set_pull(chip, gpio, false, false);
703 			if (ret < 0)
704 				goto out;
705 			break;
706 
707 		case PIN_CONFIG_DRIVE_STRENGTH:
708 			ret = iproc_gpio_set_strength(chip, gpio, arg);
709 			if (ret < 0)
710 				goto out;
711 			break;
712 
713 		default:
714 			dev_err(chip->dev, "invalid configuration\n");
715 			return -ENOTSUPP;
716 		}
717 	} /* for each config */
718 
719 out:
720 	return ret;
721 }
722 
723 static const struct pinconf_ops iproc_pconf_ops = {
724 	.is_generic = true,
725 	.pin_config_get = iproc_pin_config_get,
726 	.pin_config_set = iproc_pin_config_set,
727 };
728 
729 /*
730  * Iproc GPIO controller supports some PINCONF related configurations such as
731  * pull up, pull down, and drive strength, when the pin is configured to GPIO
732  *
733  * Here a local pinctrl device is created with simple 1-to-1 pin mapping to the
734  * local GPIO pins
735  */
736 static int iproc_gpio_register_pinconf(struct iproc_gpio *chip)
737 {
738 	struct pinctrl_desc *pctldesc = &chip->pctldesc;
739 	struct pinctrl_pin_desc *pins;
740 	struct gpio_chip *gc = &chip->gc;
741 	int i;
742 
743 	pins = devm_kcalloc(chip->dev, gc->ngpio, sizeof(*pins), GFP_KERNEL);
744 	if (!pins)
745 		return -ENOMEM;
746 
747 	for (i = 0; i < gc->ngpio; i++) {
748 		pins[i].number = i;
749 		pins[i].name = devm_kasprintf(chip->dev, GFP_KERNEL,
750 					      "gpio-%d", i);
751 		if (!pins[i].name)
752 			return -ENOMEM;
753 	}
754 
755 	pctldesc->name = dev_name(chip->dev);
756 	pctldesc->pctlops = &iproc_pctrl_ops;
757 	pctldesc->pins = pins;
758 	pctldesc->npins = gc->ngpio;
759 	pctldesc->confops = &iproc_pconf_ops;
760 
761 	chip->pctl = devm_pinctrl_register(chip->dev, pctldesc, chip);
762 	if (IS_ERR(chip->pctl)) {
763 		dev_err(chip->dev, "unable to register pinctrl device\n");
764 		return PTR_ERR(chip->pctl);
765 	}
766 
767 	return 0;
768 }
769 
770 static const struct of_device_id iproc_gpio_of_match[] = {
771 	{ .compatible = "brcm,iproc-gpio" },
772 	{ .compatible = "brcm,cygnus-ccm-gpio" },
773 	{ .compatible = "brcm,cygnus-asiu-gpio" },
774 	{ .compatible = "brcm,cygnus-crmu-gpio" },
775 	{ .compatible = "brcm,iproc-nsp-gpio" },
776 	{ .compatible = "brcm,iproc-stingray-gpio" },
777 	{ /* sentinel */ }
778 };
779 
780 static int iproc_gpio_probe(struct platform_device *pdev)
781 {
782 	struct device *dev = &pdev->dev;
783 	struct resource *res;
784 	struct iproc_gpio *chip;
785 	struct gpio_chip *gc;
786 	u32 ngpios, pinconf_disable_mask = 0;
787 	int irq, ret;
788 	bool no_pinconf = false;
789 	enum iproc_pinconf_ctrl_type io_ctrl_type = IOCTRL_TYPE_INVALID;
790 
791 	/* NSP does not support drive strength config */
792 	if (of_device_is_compatible(dev->of_node, "brcm,iproc-nsp-gpio"))
793 		pinconf_disable_mask = BIT(IPROC_PINCONF_DRIVE_STRENGTH);
794 	/* Stingray does not support pinconf in this controller */
795 	else if (of_device_is_compatible(dev->of_node,
796 					 "brcm,iproc-stingray-gpio"))
797 		no_pinconf = true;
798 
799 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
800 	if (!chip)
801 		return -ENOMEM;
802 
803 	chip->dev = dev;
804 	platform_set_drvdata(pdev, chip);
805 
806 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
807 	chip->base = devm_ioremap_resource(dev, res);
808 	if (IS_ERR(chip->base)) {
809 		dev_err(dev, "unable to map I/O memory\n");
810 		return PTR_ERR(chip->base);
811 	}
812 
813 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
814 	if (res) {
815 		chip->io_ctrl = devm_ioremap_resource(dev, res);
816 		if (IS_ERR(chip->io_ctrl)) {
817 			dev_err(dev, "unable to map I/O memory\n");
818 			return PTR_ERR(chip->io_ctrl);
819 		}
820 		if (of_device_is_compatible(dev->of_node,
821 					    "brcm,cygnus-ccm-gpio"))
822 			io_ctrl_type = IOCTRL_TYPE_CDRU;
823 		else
824 			io_ctrl_type = IOCTRL_TYPE_AON;
825 	}
826 
827 	chip->io_ctrl_type = io_ctrl_type;
828 
829 	if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) {
830 		dev_err(&pdev->dev, "missing ngpios DT property\n");
831 		return -ENODEV;
832 	}
833 
834 	raw_spin_lock_init(&chip->lock);
835 
836 	gc = &chip->gc;
837 	gc->base = -1;
838 	gc->ngpio = ngpios;
839 	chip->num_banks = (ngpios + NGPIOS_PER_BANK - 1) / NGPIOS_PER_BANK;
840 	gc->label = dev_name(dev);
841 	gc->parent = dev;
842 	gc->of_node = dev->of_node;
843 	gc->request = iproc_gpio_request;
844 	gc->free = iproc_gpio_free;
845 	gc->direction_input = iproc_gpio_direction_input;
846 	gc->direction_output = iproc_gpio_direction_output;
847 	gc->get_direction = iproc_gpio_get_direction;
848 	gc->set = iproc_gpio_set;
849 	gc->get = iproc_gpio_get;
850 
851 	chip->pinmux_is_supported = of_property_read_bool(dev->of_node,
852 							"gpio-ranges");
853 
854 	/* optional GPIO interrupt support */
855 	irq = platform_get_irq(pdev, 0);
856 	if (irq) {
857 		struct irq_chip *irqc;
858 		struct gpio_irq_chip *girq;
859 
860 		irqc = &chip->irqchip;
861 		irqc->name = "bcm-iproc-gpio";
862 		irqc->irq_ack = iproc_gpio_irq_ack;
863 		irqc->irq_mask = iproc_gpio_irq_mask;
864 		irqc->irq_unmask = iproc_gpio_irq_unmask;
865 		irqc->irq_set_type = iproc_gpio_irq_set_type;
866 		irqc->irq_enable = iproc_gpio_irq_unmask;
867 		irqc->irq_disable = iproc_gpio_irq_mask;
868 
869 		girq = &gc->irq;
870 		girq->chip = irqc;
871 		girq->parent_handler = iproc_gpio_irq_handler;
872 		girq->num_parents = 1;
873 		girq->parents = devm_kcalloc(dev, 1,
874 					     sizeof(*girq->parents),
875 					     GFP_KERNEL);
876 		if (!girq->parents)
877 			return -ENOMEM;
878 		girq->parents[0] = irq;
879 		girq->default_type = IRQ_TYPE_NONE;
880 		girq->handler = handle_simple_irq;
881 	}
882 
883 	ret = gpiochip_add_data(gc, chip);
884 	if (ret < 0) {
885 		dev_err(dev, "unable to add GPIO chip\n");
886 		return ret;
887 	}
888 
889 	if (!no_pinconf) {
890 		ret = iproc_gpio_register_pinconf(chip);
891 		if (ret) {
892 			dev_err(dev, "unable to register pinconf\n");
893 			goto err_rm_gpiochip;
894 		}
895 
896 		if (pinconf_disable_mask) {
897 			ret = iproc_pinconf_disable_map_create(chip,
898 							 pinconf_disable_mask);
899 			if (ret) {
900 				dev_err(dev,
901 					"unable to create pinconf disable map\n");
902 				goto err_rm_gpiochip;
903 			}
904 		}
905 	}
906 
907 	return 0;
908 
909 err_rm_gpiochip:
910 	gpiochip_remove(gc);
911 
912 	return ret;
913 }
914 
915 static struct platform_driver iproc_gpio_driver = {
916 	.driver = {
917 		.name = "iproc-gpio",
918 		.of_match_table = iproc_gpio_of_match,
919 	},
920 	.probe = iproc_gpio_probe,
921 };
922 
923 static int __init iproc_gpio_init(void)
924 {
925 	return platform_driver_register(&iproc_gpio_driver);
926 }
927 arch_initcall_sync(iproc_gpio_init);
928