1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014-2017 Broadcom
4  */
5 
6 /*
7  * This file contains the Broadcom Iproc GPIO driver that supports 3
8  * GPIO controllers on Iproc including the ASIU GPIO controller, the
9  * chipCommonG GPIO controller, and the always-on GPIO controller. Basic
10  * PINCONF such as bias pull up/down, and drive strength are also supported
11  * in this driver.
12  *
13  * It provides the functionality where pins from the GPIO can be
14  * individually muxed to GPIO function, if individual pad
15  * configuration is supported, through the interaction with respective
16  * SoCs IOMUX controller.
17  */
18 
19 #include <linux/gpio/driver.h>
20 #include <linux/interrupt.h>
21 #include <linux/io.h>
22 #include <linux/ioport.h>
23 #include <linux/kernel.h>
24 #include <linux/of.h>
25 #include <linux/platform_device.h>
26 #include <linux/seq_file.h>
27 #include <linux/slab.h>
28 
29 #include <linux/pinctrl/consumer.h>
30 #include <linux/pinctrl/pinconf-generic.h>
31 #include <linux/pinctrl/pinconf.h>
32 #include <linux/pinctrl/pinctrl.h>
33 
34 #include "../pinctrl-utils.h"
35 
36 #define IPROC_GPIO_DATA_IN_OFFSET   0x00
37 #define IPROC_GPIO_DATA_OUT_OFFSET  0x04
38 #define IPROC_GPIO_OUT_EN_OFFSET    0x08
39 #define IPROC_GPIO_INT_TYPE_OFFSET  0x0c
40 #define IPROC_GPIO_INT_DE_OFFSET    0x10
41 #define IPROC_GPIO_INT_EDGE_OFFSET  0x14
42 #define IPROC_GPIO_INT_MSK_OFFSET   0x18
43 #define IPROC_GPIO_INT_STAT_OFFSET  0x1c
44 #define IPROC_GPIO_INT_MSTAT_OFFSET 0x20
45 #define IPROC_GPIO_INT_CLR_OFFSET   0x24
46 #define IPROC_GPIO_PAD_RES_OFFSET   0x34
47 #define IPROC_GPIO_RES_EN_OFFSET    0x38
48 
49 /* drive strength control for ASIU GPIO */
50 #define IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET 0x58
51 
52 /* pinconf for CCM GPIO */
53 #define IPROC_GPIO_PULL_DN_OFFSET   0x10
54 #define IPROC_GPIO_PULL_UP_OFFSET   0x14
55 
56 /* pinconf for CRMU(aon) GPIO and CCM GPIO*/
57 #define IPROC_GPIO_DRV_CTRL_OFFSET  0x00
58 
59 #define GPIO_BANK_SIZE 0x200
60 #define NGPIOS_PER_BANK 32
61 #define GPIO_BANK(pin) ((pin) / NGPIOS_PER_BANK)
62 
63 #define IPROC_GPIO_REG(pin, reg) (GPIO_BANK(pin) * GPIO_BANK_SIZE + (reg))
64 #define IPROC_GPIO_SHIFT(pin) ((pin) % NGPIOS_PER_BANK)
65 
66 #define GPIO_DRV_STRENGTH_BIT_SHIFT  20
67 #define GPIO_DRV_STRENGTH_BITS       3
68 #define GPIO_DRV_STRENGTH_BIT_MASK   ((1 << GPIO_DRV_STRENGTH_BITS) - 1)
69 
70 enum iproc_pinconf_param {
71 	IPROC_PINCONF_DRIVE_STRENGTH = 0,
72 	IPROC_PINCONF_BIAS_DISABLE,
73 	IPROC_PINCONF_BIAS_PULL_UP,
74 	IPROC_PINCONF_BIAS_PULL_DOWN,
75 	IPROC_PINCON_MAX,
76 };
77 
78 enum iproc_pinconf_ctrl_type {
79 	IOCTRL_TYPE_AON = 1,
80 	IOCTRL_TYPE_CDRU,
81 	IOCTRL_TYPE_INVALID,
82 };
83 
84 /*
85  * Iproc GPIO core
86  *
87  * @dev: pointer to device
88  * @base: I/O register base for Iproc GPIO controller
89  * @io_ctrl: I/O register base for certain type of Iproc GPIO controller that
90  * has the PINCONF support implemented outside of the GPIO block
91  * @lock: lock to protect access to I/O registers
92  * @gc: GPIO chip
93  * @num_banks: number of GPIO banks, each bank supports up to 32 GPIOs
94  * @pinmux_is_supported: flag to indicate this GPIO controller contains pins
95  * that can be individually muxed to GPIO
96  * @pinconf_disable: contains a list of PINCONF parameters that need to be
97  * disabled
98  * @nr_pinconf_disable: total number of PINCONF parameters that need to be
99  * disabled
100  * @pctl: pointer to pinctrl_dev
101  * @pctldesc: pinctrl descriptor
102  */
103 struct iproc_gpio {
104 	struct device *dev;
105 
106 	void __iomem *base;
107 	void __iomem *io_ctrl;
108 	enum iproc_pinconf_ctrl_type io_ctrl_type;
109 
110 	raw_spinlock_t lock;
111 
112 	struct gpio_chip gc;
113 	unsigned num_banks;
114 
115 	bool pinmux_is_supported;
116 
117 	enum pin_config_param *pinconf_disable;
118 	unsigned int nr_pinconf_disable;
119 
120 	struct pinctrl_dev *pctl;
121 	struct pinctrl_desc pctldesc;
122 };
123 
124 /*
125  * Mapping from PINCONF pins to GPIO pins is 1-to-1
126  */
127 static inline unsigned iproc_pin_to_gpio(unsigned pin)
128 {
129 	return pin;
130 }
131 
132 /**
133  *  iproc_set_bit - set or clear one bit (corresponding to the GPIO pin) in a
134  *  Iproc GPIO register
135  *
136  *  @chip: Iproc GPIO device
137  *  @reg: register offset
138  *  @gpio: GPIO pin
139  *  @set: set or clear
140  */
141 static inline void iproc_set_bit(struct iproc_gpio *chip, unsigned int reg,
142 				  unsigned gpio, bool set)
143 {
144 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
145 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
146 	u32 val;
147 
148 	val = readl(chip->base + offset);
149 	if (set)
150 		val |= BIT(shift);
151 	else
152 		val &= ~BIT(shift);
153 	writel(val, chip->base + offset);
154 }
155 
156 static inline bool iproc_get_bit(struct iproc_gpio *chip, unsigned int reg,
157 				  unsigned gpio)
158 {
159 	unsigned int offset = IPROC_GPIO_REG(gpio, reg);
160 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
161 
162 	return !!(readl(chip->base + offset) & BIT(shift));
163 }
164 
165 static void iproc_gpio_irq_handler(struct irq_desc *desc)
166 {
167 	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
168 	struct iproc_gpio *chip = gpiochip_get_data(gc);
169 	struct irq_chip *irq_chip = irq_desc_get_chip(desc);
170 	int i, bit;
171 
172 	chained_irq_enter(irq_chip, desc);
173 
174 	/* go through the entire GPIO banks and handle all interrupts */
175 	for (i = 0; i < chip->num_banks; i++) {
176 		unsigned long val = readl(chip->base + (i * GPIO_BANK_SIZE) +
177 					  IPROC_GPIO_INT_MSTAT_OFFSET);
178 
179 		for_each_set_bit(bit, &val, NGPIOS_PER_BANK) {
180 			unsigned pin = NGPIOS_PER_BANK * i + bit;
181 
182 			/*
183 			 * Clear the interrupt before invoking the
184 			 * handler, so we do not leave any window
185 			 */
186 			writel(BIT(bit), chip->base + (i * GPIO_BANK_SIZE) +
187 			       IPROC_GPIO_INT_CLR_OFFSET);
188 
189 			generic_handle_domain_irq(gc->irq.domain, pin);
190 		}
191 	}
192 
193 	chained_irq_exit(irq_chip, desc);
194 }
195 
196 
197 static void iproc_gpio_irq_ack(struct irq_data *d)
198 {
199 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
200 	struct iproc_gpio *chip = gpiochip_get_data(gc);
201 	unsigned gpio = d->hwirq;
202 	unsigned int offset = IPROC_GPIO_REG(gpio,
203 			IPROC_GPIO_INT_CLR_OFFSET);
204 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
205 	u32 val = BIT(shift);
206 
207 	writel(val, chip->base + offset);
208 }
209 
210 /**
211  *  iproc_gpio_irq_set_mask - mask/unmask a GPIO interrupt
212  *
213  *  @d: IRQ chip data
214  *  @unmask: mask/unmask GPIO interrupt
215  */
216 static void iproc_gpio_irq_set_mask(struct irq_data *d, bool unmask)
217 {
218 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
219 	struct iproc_gpio *chip = gpiochip_get_data(gc);
220 	unsigned gpio = irqd_to_hwirq(d);
221 
222 	iproc_set_bit(chip, IPROC_GPIO_INT_MSK_OFFSET, gpio, unmask);
223 }
224 
225 static void iproc_gpio_irq_mask(struct irq_data *d)
226 {
227 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
228 	struct iproc_gpio *chip = gpiochip_get_data(gc);
229 	unsigned long flags;
230 
231 	raw_spin_lock_irqsave(&chip->lock, flags);
232 	iproc_gpio_irq_set_mask(d, false);
233 	raw_spin_unlock_irqrestore(&chip->lock, flags);
234 	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
235 }
236 
237 static void iproc_gpio_irq_unmask(struct irq_data *d)
238 {
239 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
240 	struct iproc_gpio *chip = gpiochip_get_data(gc);
241 	unsigned long flags;
242 
243 	gpiochip_enable_irq(gc, irqd_to_hwirq(d));
244 	raw_spin_lock_irqsave(&chip->lock, flags);
245 	iproc_gpio_irq_set_mask(d, true);
246 	raw_spin_unlock_irqrestore(&chip->lock, flags);
247 }
248 
249 static int iproc_gpio_irq_set_type(struct irq_data *d, unsigned int type)
250 {
251 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
252 	struct iproc_gpio *chip = gpiochip_get_data(gc);
253 	unsigned gpio = d->hwirq;
254 	bool level_triggered = false;
255 	bool dual_edge = false;
256 	bool rising_or_high = false;
257 	unsigned long flags;
258 
259 	switch (type & IRQ_TYPE_SENSE_MASK) {
260 	case IRQ_TYPE_EDGE_RISING:
261 		rising_or_high = true;
262 		break;
263 
264 	case IRQ_TYPE_EDGE_FALLING:
265 		break;
266 
267 	case IRQ_TYPE_EDGE_BOTH:
268 		dual_edge = true;
269 		break;
270 
271 	case IRQ_TYPE_LEVEL_HIGH:
272 		level_triggered = true;
273 		rising_or_high = true;
274 		break;
275 
276 	case IRQ_TYPE_LEVEL_LOW:
277 		level_triggered = true;
278 		break;
279 
280 	default:
281 		dev_err(chip->dev, "invalid GPIO IRQ type 0x%x\n",
282 			type);
283 		return -EINVAL;
284 	}
285 
286 	raw_spin_lock_irqsave(&chip->lock, flags);
287 	iproc_set_bit(chip, IPROC_GPIO_INT_TYPE_OFFSET, gpio,
288 		       level_triggered);
289 	iproc_set_bit(chip, IPROC_GPIO_INT_DE_OFFSET, gpio, dual_edge);
290 	iproc_set_bit(chip, IPROC_GPIO_INT_EDGE_OFFSET, gpio,
291 		       rising_or_high);
292 
293 	if (type & IRQ_TYPE_EDGE_BOTH)
294 		irq_set_handler_locked(d, handle_edge_irq);
295 	else
296 		irq_set_handler_locked(d, handle_level_irq);
297 
298 	raw_spin_unlock_irqrestore(&chip->lock, flags);
299 
300 	dev_dbg(chip->dev,
301 		"gpio:%u level_triggered:%d dual_edge:%d rising_or_high:%d\n",
302 		gpio, level_triggered, dual_edge, rising_or_high);
303 
304 	return 0;
305 }
306 
307 static void iproc_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
308 {
309 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
310 	struct iproc_gpio *chip = gpiochip_get_data(gc);
311 
312 	seq_printf(p, dev_name(chip->dev));
313 }
314 
315 static const struct irq_chip iproc_gpio_irq_chip = {
316 	.irq_ack = iproc_gpio_irq_ack,
317 	.irq_mask = iproc_gpio_irq_mask,
318 	.irq_unmask = iproc_gpio_irq_unmask,
319 	.irq_set_type = iproc_gpio_irq_set_type,
320 	.irq_enable = iproc_gpio_irq_unmask,
321 	.irq_disable = iproc_gpio_irq_mask,
322 	.irq_print_chip = iproc_gpio_irq_print_chip,
323 	.flags = IRQCHIP_IMMUTABLE,
324 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
325 };
326 
327 /*
328  * Request the Iproc IOMUX pinmux controller to mux individual pins to GPIO
329  */
330 static int iproc_gpio_request(struct gpio_chip *gc, unsigned offset)
331 {
332 	struct iproc_gpio *chip = gpiochip_get_data(gc);
333 	unsigned gpio = gc->base + offset;
334 
335 	/* not all Iproc GPIO pins can be muxed individually */
336 	if (!chip->pinmux_is_supported)
337 		return 0;
338 
339 	return pinctrl_gpio_request(gpio);
340 }
341 
342 static void iproc_gpio_free(struct gpio_chip *gc, unsigned offset)
343 {
344 	struct iproc_gpio *chip = gpiochip_get_data(gc);
345 	unsigned gpio = gc->base + offset;
346 
347 	if (!chip->pinmux_is_supported)
348 		return;
349 
350 	pinctrl_gpio_free(gpio);
351 }
352 
353 static int iproc_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
354 {
355 	struct iproc_gpio *chip = gpiochip_get_data(gc);
356 	unsigned long flags;
357 
358 	raw_spin_lock_irqsave(&chip->lock, flags);
359 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, false);
360 	raw_spin_unlock_irqrestore(&chip->lock, flags);
361 
362 	dev_dbg(chip->dev, "gpio:%u set input\n", gpio);
363 
364 	return 0;
365 }
366 
367 static int iproc_gpio_direction_output(struct gpio_chip *gc, unsigned gpio,
368 					int val)
369 {
370 	struct iproc_gpio *chip = gpiochip_get_data(gc);
371 	unsigned long flags;
372 
373 	raw_spin_lock_irqsave(&chip->lock, flags);
374 	iproc_set_bit(chip, IPROC_GPIO_OUT_EN_OFFSET, gpio, true);
375 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
376 	raw_spin_unlock_irqrestore(&chip->lock, flags);
377 
378 	dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val);
379 
380 	return 0;
381 }
382 
383 static int iproc_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio)
384 {
385 	struct iproc_gpio *chip = gpiochip_get_data(gc);
386 	unsigned int offset = IPROC_GPIO_REG(gpio, IPROC_GPIO_OUT_EN_OFFSET);
387 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
388 
389 	if (readl(chip->base + offset) & BIT(shift))
390 		return GPIO_LINE_DIRECTION_OUT;
391 
392 	return GPIO_LINE_DIRECTION_IN;
393 }
394 
395 static void iproc_gpio_set(struct gpio_chip *gc, unsigned gpio, int val)
396 {
397 	struct iproc_gpio *chip = gpiochip_get_data(gc);
398 	unsigned long flags;
399 
400 	raw_spin_lock_irqsave(&chip->lock, flags);
401 	iproc_set_bit(chip, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val));
402 	raw_spin_unlock_irqrestore(&chip->lock, flags);
403 
404 	dev_dbg(chip->dev, "gpio:%u set, value:%d\n", gpio, val);
405 }
406 
407 static int iproc_gpio_get(struct gpio_chip *gc, unsigned gpio)
408 {
409 	struct iproc_gpio *chip = gpiochip_get_data(gc);
410 	unsigned int offset = IPROC_GPIO_REG(gpio,
411 					      IPROC_GPIO_DATA_IN_OFFSET);
412 	unsigned int shift = IPROC_GPIO_SHIFT(gpio);
413 
414 	return !!(readl(chip->base + offset) & BIT(shift));
415 }
416 
417 /*
418  * Mapping of the iProc PINCONF parameters to the generic pin configuration
419  * parameters
420  */
421 static const enum pin_config_param iproc_pinconf_disable_map[] = {
422 	[IPROC_PINCONF_DRIVE_STRENGTH] = PIN_CONFIG_DRIVE_STRENGTH,
423 	[IPROC_PINCONF_BIAS_DISABLE] = PIN_CONFIG_BIAS_DISABLE,
424 	[IPROC_PINCONF_BIAS_PULL_UP] = PIN_CONFIG_BIAS_PULL_UP,
425 	[IPROC_PINCONF_BIAS_PULL_DOWN] = PIN_CONFIG_BIAS_PULL_DOWN,
426 };
427 
428 static bool iproc_pinconf_param_is_disabled(struct iproc_gpio *chip,
429 					    enum pin_config_param param)
430 {
431 	unsigned int i;
432 
433 	if (!chip->nr_pinconf_disable)
434 		return false;
435 
436 	for (i = 0; i < chip->nr_pinconf_disable; i++)
437 		if (chip->pinconf_disable[i] == param)
438 			return true;
439 
440 	return false;
441 }
442 
443 static int iproc_pinconf_disable_map_create(struct iproc_gpio *chip,
444 					    unsigned long disable_mask)
445 {
446 	unsigned int map_size = ARRAY_SIZE(iproc_pinconf_disable_map);
447 	unsigned int bit, nbits = 0;
448 
449 	/* figure out total number of PINCONF parameters to disable */
450 	for_each_set_bit(bit, &disable_mask, map_size)
451 		nbits++;
452 
453 	if (!nbits)
454 		return 0;
455 
456 	/*
457 	 * Allocate an array to store PINCONF parameters that need to be
458 	 * disabled
459 	 */
460 	chip->pinconf_disable = devm_kcalloc(chip->dev, nbits,
461 					     sizeof(*chip->pinconf_disable),
462 					     GFP_KERNEL);
463 	if (!chip->pinconf_disable)
464 		return -ENOMEM;
465 
466 	chip->nr_pinconf_disable = nbits;
467 
468 	/* now store these parameters */
469 	nbits = 0;
470 	for_each_set_bit(bit, &disable_mask, map_size)
471 		chip->pinconf_disable[nbits++] = iproc_pinconf_disable_map[bit];
472 
473 	return 0;
474 }
475 
476 static int iproc_get_groups_count(struct pinctrl_dev *pctldev)
477 {
478 	return 1;
479 }
480 
481 /*
482  * Only one group: "gpio_grp", since this local pinctrl device only performs
483  * GPIO specific PINCONF configurations
484  */
485 static const char *iproc_get_group_name(struct pinctrl_dev *pctldev,
486 					 unsigned selector)
487 {
488 	return "gpio_grp";
489 }
490 
491 static const struct pinctrl_ops iproc_pctrl_ops = {
492 	.get_groups_count = iproc_get_groups_count,
493 	.get_group_name = iproc_get_group_name,
494 	.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
495 	.dt_free_map = pinctrl_utils_free_map,
496 };
497 
498 static int iproc_gpio_set_pull(struct iproc_gpio *chip, unsigned gpio,
499 				bool disable, bool pull_up)
500 {
501 	void __iomem *base;
502 	unsigned long flags;
503 	unsigned int shift;
504 	u32 val_1, val_2;
505 
506 	raw_spin_lock_irqsave(&chip->lock, flags);
507 	if (chip->io_ctrl_type == IOCTRL_TYPE_CDRU) {
508 		base = chip->io_ctrl;
509 		shift = IPROC_GPIO_SHIFT(gpio);
510 
511 		val_1 = readl(base + IPROC_GPIO_PULL_UP_OFFSET);
512 		val_2 = readl(base + IPROC_GPIO_PULL_DN_OFFSET);
513 		if (disable) {
514 			/* no pull-up or pull-down */
515 			val_1 &= ~BIT(shift);
516 			val_2 &= ~BIT(shift);
517 		} else if (pull_up) {
518 			val_1 |= BIT(shift);
519 			val_2 &= ~BIT(shift);
520 		} else {
521 			val_1 &= ~BIT(shift);
522 			val_2 |= BIT(shift);
523 		}
524 		writel(val_1, base + IPROC_GPIO_PULL_UP_OFFSET);
525 		writel(val_2, base + IPROC_GPIO_PULL_DN_OFFSET);
526 	} else {
527 		if (disable) {
528 			iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio,
529 				      false);
530 		} else {
531 			iproc_set_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio,
532 				      pull_up);
533 			iproc_set_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio,
534 				      true);
535 		}
536 	}
537 
538 	raw_spin_unlock_irqrestore(&chip->lock, flags);
539 	dev_dbg(chip->dev, "gpio:%u set pullup:%d\n", gpio, pull_up);
540 
541 	return 0;
542 }
543 
544 static void iproc_gpio_get_pull(struct iproc_gpio *chip, unsigned gpio,
545 				 bool *disable, bool *pull_up)
546 {
547 	void __iomem *base;
548 	unsigned long flags;
549 	unsigned int shift;
550 	u32 val_1, val_2;
551 
552 	raw_spin_lock_irqsave(&chip->lock, flags);
553 	if (chip->io_ctrl_type == IOCTRL_TYPE_CDRU) {
554 		base = chip->io_ctrl;
555 		shift = IPROC_GPIO_SHIFT(gpio);
556 
557 		val_1 = readl(base + IPROC_GPIO_PULL_UP_OFFSET) & BIT(shift);
558 		val_2 = readl(base + IPROC_GPIO_PULL_DN_OFFSET) & BIT(shift);
559 
560 		*pull_up = val_1 ? true : false;
561 		*disable = (val_1 | val_2) ? false : true;
562 
563 	} else {
564 		*disable = !iproc_get_bit(chip, IPROC_GPIO_RES_EN_OFFSET, gpio);
565 		*pull_up = iproc_get_bit(chip, IPROC_GPIO_PAD_RES_OFFSET, gpio);
566 	}
567 	raw_spin_unlock_irqrestore(&chip->lock, flags);
568 }
569 
570 #define DRV_STRENGTH_OFFSET(gpio, bit, type)  ((type) == IOCTRL_TYPE_AON ? \
571 	((2 - (bit)) * 4 + IPROC_GPIO_DRV_CTRL_OFFSET) : \
572 	((type) == IOCTRL_TYPE_CDRU) ? \
573 	((bit) * 4 + IPROC_GPIO_DRV_CTRL_OFFSET) : \
574 	((bit) * 4 + IPROC_GPIO_REG(gpio, IPROC_GPIO_ASIU_DRV0_CTRL_OFFSET)))
575 
576 static int iproc_gpio_set_strength(struct iproc_gpio *chip, unsigned gpio,
577 				    unsigned strength)
578 {
579 	void __iomem *base;
580 	unsigned int i, offset, shift;
581 	u32 val;
582 	unsigned long flags;
583 
584 	/* make sure drive strength is supported */
585 	if (strength < 2 ||  strength > 16 || (strength % 2))
586 		return -ENOTSUPP;
587 
588 	if (chip->io_ctrl) {
589 		base = chip->io_ctrl;
590 	} else {
591 		base = chip->base;
592 	}
593 
594 	shift = IPROC_GPIO_SHIFT(gpio);
595 
596 	dev_dbg(chip->dev, "gpio:%u set drive strength:%d mA\n", gpio,
597 		strength);
598 
599 	raw_spin_lock_irqsave(&chip->lock, flags);
600 	strength = (strength / 2) - 1;
601 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
602 		offset = DRV_STRENGTH_OFFSET(gpio, i, chip->io_ctrl_type);
603 		val = readl(base + offset);
604 		val &= ~BIT(shift);
605 		val |= ((strength >> i) & 0x1) << shift;
606 		writel(val, base + offset);
607 	}
608 	raw_spin_unlock_irqrestore(&chip->lock, flags);
609 
610 	return 0;
611 }
612 
613 static int iproc_gpio_get_strength(struct iproc_gpio *chip, unsigned gpio,
614 				    u16 *strength)
615 {
616 	void __iomem *base;
617 	unsigned int i, offset, shift;
618 	u32 val;
619 	unsigned long flags;
620 
621 	if (chip->io_ctrl) {
622 		base = chip->io_ctrl;
623 	} else {
624 		base = chip->base;
625 	}
626 
627 	shift = IPROC_GPIO_SHIFT(gpio);
628 
629 	raw_spin_lock_irqsave(&chip->lock, flags);
630 	*strength = 0;
631 	for (i = 0; i < GPIO_DRV_STRENGTH_BITS; i++) {
632 		offset = DRV_STRENGTH_OFFSET(gpio, i, chip->io_ctrl_type);
633 		val = readl(base + offset) & BIT(shift);
634 		val >>= shift;
635 		*strength += (val << i);
636 	}
637 
638 	/* convert to mA */
639 	*strength = (*strength + 1) * 2;
640 	raw_spin_unlock_irqrestore(&chip->lock, flags);
641 
642 	return 0;
643 }
644 
645 static int iproc_pin_config_get(struct pinctrl_dev *pctldev, unsigned pin,
646 				 unsigned long *config)
647 {
648 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
649 	enum pin_config_param param = pinconf_to_config_param(*config);
650 	unsigned gpio = iproc_pin_to_gpio(pin);
651 	u16 arg;
652 	bool disable, pull_up;
653 	int ret;
654 
655 	if (iproc_pinconf_param_is_disabled(chip, param))
656 		return -ENOTSUPP;
657 
658 	switch (param) {
659 	case PIN_CONFIG_BIAS_DISABLE:
660 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
661 		if (disable)
662 			return 0;
663 		else
664 			return -EINVAL;
665 
666 	case PIN_CONFIG_BIAS_PULL_UP:
667 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
668 		if (!disable && pull_up)
669 			return 0;
670 		else
671 			return -EINVAL;
672 
673 	case PIN_CONFIG_BIAS_PULL_DOWN:
674 		iproc_gpio_get_pull(chip, gpio, &disable, &pull_up);
675 		if (!disable && !pull_up)
676 			return 0;
677 		else
678 			return -EINVAL;
679 
680 	case PIN_CONFIG_DRIVE_STRENGTH:
681 		ret = iproc_gpio_get_strength(chip, gpio, &arg);
682 		if (ret)
683 			return ret;
684 		*config = pinconf_to_config_packed(param, arg);
685 
686 		return 0;
687 
688 	default:
689 		return -ENOTSUPP;
690 	}
691 
692 	return -ENOTSUPP;
693 }
694 
695 static int iproc_pin_config_set(struct pinctrl_dev *pctldev, unsigned pin,
696 				 unsigned long *configs, unsigned num_configs)
697 {
698 	struct iproc_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
699 	enum pin_config_param param;
700 	u32 arg;
701 	unsigned i, gpio = iproc_pin_to_gpio(pin);
702 	int ret = -ENOTSUPP;
703 
704 	for (i = 0; i < num_configs; i++) {
705 		param = pinconf_to_config_param(configs[i]);
706 
707 		if (iproc_pinconf_param_is_disabled(chip, param))
708 			return -ENOTSUPP;
709 
710 		arg = pinconf_to_config_argument(configs[i]);
711 
712 		switch (param) {
713 		case PIN_CONFIG_BIAS_DISABLE:
714 			ret = iproc_gpio_set_pull(chip, gpio, true, false);
715 			if (ret < 0)
716 				goto out;
717 			break;
718 
719 		case PIN_CONFIG_BIAS_PULL_UP:
720 			ret = iproc_gpio_set_pull(chip, gpio, false, true);
721 			if (ret < 0)
722 				goto out;
723 			break;
724 
725 		case PIN_CONFIG_BIAS_PULL_DOWN:
726 			ret = iproc_gpio_set_pull(chip, gpio, false, false);
727 			if (ret < 0)
728 				goto out;
729 			break;
730 
731 		case PIN_CONFIG_DRIVE_STRENGTH:
732 			ret = iproc_gpio_set_strength(chip, gpio, arg);
733 			if (ret < 0)
734 				goto out;
735 			break;
736 
737 		default:
738 			dev_err(chip->dev, "invalid configuration\n");
739 			return -ENOTSUPP;
740 		}
741 	} /* for each config */
742 
743 out:
744 	return ret;
745 }
746 
747 static const struct pinconf_ops iproc_pconf_ops = {
748 	.is_generic = true,
749 	.pin_config_get = iproc_pin_config_get,
750 	.pin_config_set = iproc_pin_config_set,
751 };
752 
753 /*
754  * Iproc GPIO controller supports some PINCONF related configurations such as
755  * pull up, pull down, and drive strength, when the pin is configured to GPIO
756  *
757  * Here a local pinctrl device is created with simple 1-to-1 pin mapping to the
758  * local GPIO pins
759  */
760 static int iproc_gpio_register_pinconf(struct iproc_gpio *chip)
761 {
762 	struct pinctrl_desc *pctldesc = &chip->pctldesc;
763 	struct pinctrl_pin_desc *pins;
764 	struct gpio_chip *gc = &chip->gc;
765 	int i;
766 
767 	pins = devm_kcalloc(chip->dev, gc->ngpio, sizeof(*pins), GFP_KERNEL);
768 	if (!pins)
769 		return -ENOMEM;
770 
771 	for (i = 0; i < gc->ngpio; i++) {
772 		pins[i].number = i;
773 		pins[i].name = devm_kasprintf(chip->dev, GFP_KERNEL,
774 					      "gpio-%d", i);
775 		if (!pins[i].name)
776 			return -ENOMEM;
777 	}
778 
779 	pctldesc->name = dev_name(chip->dev);
780 	pctldesc->pctlops = &iproc_pctrl_ops;
781 	pctldesc->pins = pins;
782 	pctldesc->npins = gc->ngpio;
783 	pctldesc->confops = &iproc_pconf_ops;
784 
785 	chip->pctl = devm_pinctrl_register(chip->dev, pctldesc, chip);
786 	if (IS_ERR(chip->pctl)) {
787 		dev_err(chip->dev, "unable to register pinctrl device\n");
788 		return PTR_ERR(chip->pctl);
789 	}
790 
791 	return 0;
792 }
793 
794 static const struct of_device_id iproc_gpio_of_match[] = {
795 	{ .compatible = "brcm,iproc-gpio" },
796 	{ .compatible = "brcm,cygnus-ccm-gpio" },
797 	{ .compatible = "brcm,cygnus-asiu-gpio" },
798 	{ .compatible = "brcm,cygnus-crmu-gpio" },
799 	{ .compatible = "brcm,iproc-nsp-gpio" },
800 	{ .compatible = "brcm,iproc-stingray-gpio" },
801 	{ /* sentinel */ }
802 };
803 
804 static int iproc_gpio_probe(struct platform_device *pdev)
805 {
806 	struct device *dev = &pdev->dev;
807 	struct resource *res;
808 	struct iproc_gpio *chip;
809 	struct gpio_chip *gc;
810 	u32 ngpios, pinconf_disable_mask = 0;
811 	int irq, ret;
812 	bool no_pinconf = false;
813 	enum iproc_pinconf_ctrl_type io_ctrl_type = IOCTRL_TYPE_INVALID;
814 
815 	/* NSP does not support drive strength config */
816 	if (of_device_is_compatible(dev->of_node, "brcm,iproc-nsp-gpio"))
817 		pinconf_disable_mask = BIT(IPROC_PINCONF_DRIVE_STRENGTH);
818 	/* Stingray does not support pinconf in this controller */
819 	else if (of_device_is_compatible(dev->of_node,
820 					 "brcm,iproc-stingray-gpio"))
821 		no_pinconf = true;
822 
823 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
824 	if (!chip)
825 		return -ENOMEM;
826 
827 	chip->dev = dev;
828 	platform_set_drvdata(pdev, chip);
829 
830 	chip->base = devm_platform_ioremap_resource(pdev, 0);
831 	if (IS_ERR(chip->base)) {
832 		dev_err(dev, "unable to map I/O memory\n");
833 		return PTR_ERR(chip->base);
834 	}
835 
836 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
837 	if (res) {
838 		chip->io_ctrl = devm_ioremap_resource(dev, res);
839 		if (IS_ERR(chip->io_ctrl))
840 			return PTR_ERR(chip->io_ctrl);
841 		if (of_device_is_compatible(dev->of_node,
842 					    "brcm,cygnus-ccm-gpio"))
843 			io_ctrl_type = IOCTRL_TYPE_CDRU;
844 		else
845 			io_ctrl_type = IOCTRL_TYPE_AON;
846 	}
847 
848 	chip->io_ctrl_type = io_ctrl_type;
849 
850 	if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) {
851 		dev_err(&pdev->dev, "missing ngpios DT property\n");
852 		return -ENODEV;
853 	}
854 
855 	raw_spin_lock_init(&chip->lock);
856 
857 	gc = &chip->gc;
858 	gc->base = -1;
859 	gc->ngpio = ngpios;
860 	chip->num_banks = (ngpios + NGPIOS_PER_BANK - 1) / NGPIOS_PER_BANK;
861 	gc->label = dev_name(dev);
862 	gc->parent = dev;
863 	gc->request = iproc_gpio_request;
864 	gc->free = iproc_gpio_free;
865 	gc->direction_input = iproc_gpio_direction_input;
866 	gc->direction_output = iproc_gpio_direction_output;
867 	gc->get_direction = iproc_gpio_get_direction;
868 	gc->set = iproc_gpio_set;
869 	gc->get = iproc_gpio_get;
870 
871 	chip->pinmux_is_supported = of_property_read_bool(dev->of_node,
872 							"gpio-ranges");
873 
874 	/* optional GPIO interrupt support */
875 	irq = platform_get_irq_optional(pdev, 0);
876 	if (irq > 0) {
877 		struct gpio_irq_chip *girq;
878 
879 		girq = &gc->irq;
880 		gpio_irq_chip_set_chip(girq, &iproc_gpio_irq_chip);
881 		girq->parent_handler = iproc_gpio_irq_handler;
882 		girq->num_parents = 1;
883 		girq->parents = devm_kcalloc(dev, 1,
884 					     sizeof(*girq->parents),
885 					     GFP_KERNEL);
886 		if (!girq->parents)
887 			return -ENOMEM;
888 		girq->parents[0] = irq;
889 		girq->default_type = IRQ_TYPE_NONE;
890 		girq->handler = handle_bad_irq;
891 	}
892 
893 	ret = gpiochip_add_data(gc, chip);
894 	if (ret < 0)
895 		return dev_err_probe(dev, ret, "unable to add GPIO chip\n");
896 
897 	if (!no_pinconf) {
898 		ret = iproc_gpio_register_pinconf(chip);
899 		if (ret) {
900 			dev_err(dev, "unable to register pinconf\n");
901 			goto err_rm_gpiochip;
902 		}
903 
904 		if (pinconf_disable_mask) {
905 			ret = iproc_pinconf_disable_map_create(chip,
906 							 pinconf_disable_mask);
907 			if (ret) {
908 				dev_err(dev,
909 					"unable to create pinconf disable map\n");
910 				goto err_rm_gpiochip;
911 			}
912 		}
913 	}
914 
915 	return 0;
916 
917 err_rm_gpiochip:
918 	gpiochip_remove(gc);
919 
920 	return ret;
921 }
922 
923 static struct platform_driver iproc_gpio_driver = {
924 	.driver = {
925 		.name = "iproc-gpio",
926 		.of_match_table = iproc_gpio_of_match,
927 	},
928 	.probe = iproc_gpio_probe,
929 };
930 
931 static int __init iproc_gpio_init(void)
932 {
933 	return platform_driver_register(&iproc_gpio_driver);
934 }
935 arch_initcall_sync(iproc_gpio_init);
936