xref: /linux/drivers/gpio/gpio-dwapb.c (revision 8137a49e1567726eb10fcf55ad141ac19804ca6b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2011 Jamie Iles
4  *
5  * All enquiries to support@picochip.com
6  */
7 #include <linux/acpi.h>
8 #include <linux/clk.h>
9 #include <linux/err.h>
10 #include <linux/gpio/driver.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/ioport.h>
15 #include <linux/irq.h>
16 #include <linux/mod_devicetable.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/platform_data/gpio-dwapb.h>
20 #include <linux/platform_device.h>
21 #include <linux/property.h>
22 #include <linux/reset.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 
26 #include "gpiolib.h"
27 #include "gpiolib-acpi.h"
28 
29 #define GPIO_SWPORTA_DR		0x00
30 #define GPIO_SWPORTA_DDR	0x04
31 #define GPIO_SWPORTB_DR		0x0c
32 #define GPIO_SWPORTB_DDR	0x10
33 #define GPIO_SWPORTC_DR		0x18
34 #define GPIO_SWPORTC_DDR	0x1c
35 #define GPIO_SWPORTD_DR		0x24
36 #define GPIO_SWPORTD_DDR	0x28
37 #define GPIO_INTEN		0x30
38 #define GPIO_INTMASK		0x34
39 #define GPIO_INTTYPE_LEVEL	0x38
40 #define GPIO_INT_POLARITY	0x3c
41 #define GPIO_INTSTATUS		0x40
42 #define GPIO_PORTA_DEBOUNCE	0x48
43 #define GPIO_PORTA_EOI		0x4c
44 #define GPIO_EXT_PORTA		0x50
45 #define GPIO_EXT_PORTB		0x54
46 #define GPIO_EXT_PORTC		0x58
47 #define GPIO_EXT_PORTD		0x5c
48 
49 #define DWAPB_DRIVER_NAME	"gpio-dwapb"
50 #define DWAPB_MAX_PORTS		4
51 
52 #define GPIO_EXT_PORT_STRIDE	0x04 /* register stride 32 bits */
53 #define GPIO_SWPORT_DR_STRIDE	0x0c /* register stride 3*32 bits */
54 #define GPIO_SWPORT_DDR_STRIDE	0x0c /* register stride 3*32 bits */
55 
56 #define GPIO_REG_OFFSET_V2	1
57 
58 #define GPIO_INTMASK_V2		0x44
59 #define GPIO_INTTYPE_LEVEL_V2	0x34
60 #define GPIO_INT_POLARITY_V2	0x38
61 #define GPIO_INTSTATUS_V2	0x3c
62 #define GPIO_PORTA_EOI_V2	0x40
63 
64 #define DWAPB_NR_CLOCKS		2
65 
66 struct dwapb_gpio;
67 
68 #ifdef CONFIG_PM_SLEEP
69 /* Store GPIO context across system-wide suspend/resume transitions */
70 struct dwapb_context {
71 	u32 data;
72 	u32 dir;
73 	u32 ext;
74 	u32 int_en;
75 	u32 int_mask;
76 	u32 int_type;
77 	u32 int_pol;
78 	u32 int_deb;
79 	u32 wake_en;
80 };
81 #endif
82 
83 struct dwapb_gpio_port_irqchip {
84 	struct irq_chip		irqchip;
85 	unsigned int		nr_irqs;
86 	unsigned int		irq[DWAPB_MAX_GPIOS];
87 };
88 
89 struct dwapb_gpio_port {
90 	struct gpio_chip	gc;
91 	struct dwapb_gpio_port_irqchip *pirq;
92 	struct dwapb_gpio	*gpio;
93 #ifdef CONFIG_PM_SLEEP
94 	struct dwapb_context	*ctx;
95 #endif
96 	unsigned int		idx;
97 };
98 #define to_dwapb_gpio(_gc) \
99 	(container_of(_gc, struct dwapb_gpio_port, gc)->gpio)
100 
101 struct dwapb_gpio {
102 	struct	device		*dev;
103 	void __iomem		*regs;
104 	struct dwapb_gpio_port	*ports;
105 	unsigned int		nr_ports;
106 	unsigned int		flags;
107 	struct reset_control	*rst;
108 	struct clk_bulk_data	clks[DWAPB_NR_CLOCKS];
109 };
110 
111 static inline u32 gpio_reg_v2_convert(unsigned int offset)
112 {
113 	switch (offset) {
114 	case GPIO_INTMASK:
115 		return GPIO_INTMASK_V2;
116 	case GPIO_INTTYPE_LEVEL:
117 		return GPIO_INTTYPE_LEVEL_V2;
118 	case GPIO_INT_POLARITY:
119 		return GPIO_INT_POLARITY_V2;
120 	case GPIO_INTSTATUS:
121 		return GPIO_INTSTATUS_V2;
122 	case GPIO_PORTA_EOI:
123 		return GPIO_PORTA_EOI_V2;
124 	}
125 
126 	return offset;
127 }
128 
129 static inline u32 gpio_reg_convert(struct dwapb_gpio *gpio, unsigned int offset)
130 {
131 	if (gpio->flags & GPIO_REG_OFFSET_V2)
132 		return gpio_reg_v2_convert(offset);
133 
134 	return offset;
135 }
136 
137 static inline u32 dwapb_read(struct dwapb_gpio *gpio, unsigned int offset)
138 {
139 	struct gpio_chip *gc	= &gpio->ports[0].gc;
140 	void __iomem *reg_base	= gpio->regs;
141 
142 	return gc->read_reg(reg_base + gpio_reg_convert(gpio, offset));
143 }
144 
145 static inline void dwapb_write(struct dwapb_gpio *gpio, unsigned int offset,
146 			       u32 val)
147 {
148 	struct gpio_chip *gc	= &gpio->ports[0].gc;
149 	void __iomem *reg_base	= gpio->regs;
150 
151 	gc->write_reg(reg_base + gpio_reg_convert(gpio, offset), val);
152 }
153 
154 static struct dwapb_gpio_port *dwapb_offs_to_port(struct dwapb_gpio *gpio, unsigned int offs)
155 {
156 	struct dwapb_gpio_port *port;
157 	int i;
158 
159 	for (i = 0; i < gpio->nr_ports; i++) {
160 		port = &gpio->ports[i];
161 		if (port->idx == offs / DWAPB_MAX_GPIOS)
162 			return port;
163 	}
164 
165 	return NULL;
166 }
167 
168 static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
169 {
170 	struct dwapb_gpio_port *port = dwapb_offs_to_port(gpio, offs);
171 	struct gpio_chip *gc;
172 	u32 pol;
173 	int val;
174 
175 	if (!port)
176 		return;
177 	gc = &port->gc;
178 
179 	pol = dwapb_read(gpio, GPIO_INT_POLARITY);
180 	/* Just read the current value right out of the data register */
181 	val = gc->get(gc, offs % DWAPB_MAX_GPIOS);
182 	if (val)
183 		pol &= ~BIT(offs);
184 	else
185 		pol |= BIT(offs);
186 
187 	dwapb_write(gpio, GPIO_INT_POLARITY, pol);
188 }
189 
190 static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
191 {
192 	struct gpio_chip *gc = &gpio->ports[0].gc;
193 	unsigned long irq_status;
194 	irq_hw_number_t hwirq;
195 
196 	irq_status = dwapb_read(gpio, GPIO_INTSTATUS);
197 	for_each_set_bit(hwirq, &irq_status, DWAPB_MAX_GPIOS) {
198 		int gpio_irq = irq_find_mapping(gc->irq.domain, hwirq);
199 		u32 irq_type = irq_get_trigger_type(gpio_irq);
200 
201 		generic_handle_irq(gpio_irq);
202 
203 		if ((irq_type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
204 			dwapb_toggle_trigger(gpio, hwirq);
205 	}
206 
207 	return irq_status;
208 }
209 
210 static void dwapb_irq_handler(struct irq_desc *desc)
211 {
212 	struct dwapb_gpio *gpio = irq_desc_get_handler_data(desc);
213 	struct irq_chip *chip = irq_desc_get_chip(desc);
214 
215 	chained_irq_enter(chip, desc);
216 	dwapb_do_irq(gpio);
217 	chained_irq_exit(chip, desc);
218 }
219 
220 static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id)
221 {
222 	return IRQ_RETVAL(dwapb_do_irq(dev_id));
223 }
224 
225 static void dwapb_irq_ack(struct irq_data *d)
226 {
227 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
228 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
229 	u32 val = BIT(irqd_to_hwirq(d));
230 	unsigned long flags;
231 
232 	spin_lock_irqsave(&gc->bgpio_lock, flags);
233 	dwapb_write(gpio, GPIO_PORTA_EOI, val);
234 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
235 }
236 
237 static void dwapb_irq_mask(struct irq_data *d)
238 {
239 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
240 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
241 	unsigned long flags;
242 	u32 val;
243 
244 	spin_lock_irqsave(&gc->bgpio_lock, flags);
245 	val = dwapb_read(gpio, GPIO_INTMASK) | BIT(irqd_to_hwirq(d));
246 	dwapb_write(gpio, GPIO_INTMASK, val);
247 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
248 }
249 
250 static void dwapb_irq_unmask(struct irq_data *d)
251 {
252 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
253 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
254 	unsigned long flags;
255 	u32 val;
256 
257 	spin_lock_irqsave(&gc->bgpio_lock, flags);
258 	val = dwapb_read(gpio, GPIO_INTMASK) & ~BIT(irqd_to_hwirq(d));
259 	dwapb_write(gpio, GPIO_INTMASK, val);
260 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
261 }
262 
263 static void dwapb_irq_enable(struct irq_data *d)
264 {
265 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
266 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
267 	unsigned long flags;
268 	u32 val;
269 
270 	spin_lock_irqsave(&gc->bgpio_lock, flags);
271 	val = dwapb_read(gpio, GPIO_INTEN);
272 	val |= BIT(irqd_to_hwirq(d));
273 	dwapb_write(gpio, GPIO_INTEN, val);
274 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
275 }
276 
277 static void dwapb_irq_disable(struct irq_data *d)
278 {
279 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
280 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
281 	unsigned long flags;
282 	u32 val;
283 
284 	spin_lock_irqsave(&gc->bgpio_lock, flags);
285 	val = dwapb_read(gpio, GPIO_INTEN);
286 	val &= ~BIT(irqd_to_hwirq(d));
287 	dwapb_write(gpio, GPIO_INTEN, val);
288 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
289 }
290 
291 static int dwapb_irq_set_type(struct irq_data *d, u32 type)
292 {
293 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
294 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
295 	irq_hw_number_t bit = irqd_to_hwirq(d);
296 	unsigned long level, polarity, flags;
297 
298 	spin_lock_irqsave(&gc->bgpio_lock, flags);
299 	level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
300 	polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
301 
302 	switch (type) {
303 	case IRQ_TYPE_EDGE_BOTH:
304 		level |= BIT(bit);
305 		dwapb_toggle_trigger(gpio, bit);
306 		break;
307 	case IRQ_TYPE_EDGE_RISING:
308 		level |= BIT(bit);
309 		polarity |= BIT(bit);
310 		break;
311 	case IRQ_TYPE_EDGE_FALLING:
312 		level |= BIT(bit);
313 		polarity &= ~BIT(bit);
314 		break;
315 	case IRQ_TYPE_LEVEL_HIGH:
316 		level &= ~BIT(bit);
317 		polarity |= BIT(bit);
318 		break;
319 	case IRQ_TYPE_LEVEL_LOW:
320 		level &= ~BIT(bit);
321 		polarity &= ~BIT(bit);
322 		break;
323 	}
324 
325 	if (type & IRQ_TYPE_LEVEL_MASK)
326 		irq_set_handler_locked(d, handle_level_irq);
327 	else if (type & IRQ_TYPE_EDGE_BOTH)
328 		irq_set_handler_locked(d, handle_edge_irq);
329 
330 	dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level);
331 	if (type != IRQ_TYPE_EDGE_BOTH)
332 		dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
333 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
334 
335 	return 0;
336 }
337 
338 #ifdef CONFIG_PM_SLEEP
339 static int dwapb_irq_set_wake(struct irq_data *d, unsigned int enable)
340 {
341 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
342 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
343 	struct dwapb_context *ctx = gpio->ports[0].ctx;
344 	irq_hw_number_t bit = irqd_to_hwirq(d);
345 
346 	if (enable)
347 		ctx->wake_en |= BIT(bit);
348 	else
349 		ctx->wake_en &= ~BIT(bit);
350 
351 	return 0;
352 }
353 #endif
354 
355 static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
356 				   unsigned offset, unsigned debounce)
357 {
358 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
359 	struct dwapb_gpio *gpio = port->gpio;
360 	unsigned long flags, val_deb;
361 	unsigned long mask = BIT(offset);
362 
363 	spin_lock_irqsave(&gc->bgpio_lock, flags);
364 
365 	val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
366 	if (debounce)
367 		val_deb |= mask;
368 	else
369 		val_deb &= ~mask;
370 	dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb);
371 
372 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
373 
374 	return 0;
375 }
376 
377 static int dwapb_gpio_set_config(struct gpio_chip *gc, unsigned offset,
378 				 unsigned long config)
379 {
380 	u32 debounce;
381 
382 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
383 		return -ENOTSUPP;
384 
385 	debounce = pinconf_to_config_argument(config);
386 	return dwapb_gpio_set_debounce(gc, offset, debounce);
387 }
388 
389 static int dwapb_convert_irqs(struct dwapb_gpio_port_irqchip *pirq,
390 			      struct dwapb_port_property *pp)
391 {
392 	int i;
393 
394 	/* Group all available IRQs into an array of parental IRQs. */
395 	for (i = 0; i < pp->ngpio; ++i) {
396 		if (!pp->irq[i])
397 			continue;
398 
399 		pirq->irq[pirq->nr_irqs++] = pp->irq[i];
400 	}
401 
402 	return pirq->nr_irqs ? 0 : -ENOENT;
403 }
404 
405 static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
406 				 struct dwapb_gpio_port *port,
407 				 struct dwapb_port_property *pp)
408 {
409 	struct dwapb_gpio_port_irqchip *pirq;
410 	struct gpio_chip *gc = &port->gc;
411 	struct gpio_irq_chip *girq;
412 	int err;
413 
414 	pirq = devm_kzalloc(gpio->dev, sizeof(*pirq), GFP_KERNEL);
415 	if (!pirq)
416 		return;
417 
418 	if (dwapb_convert_irqs(pirq, pp)) {
419 		dev_warn(gpio->dev, "no IRQ for port%d\n", pp->idx);
420 		goto err_kfree_pirq;
421 	}
422 
423 	girq = &gc->irq;
424 	girq->handler = handle_bad_irq;
425 	girq->default_type = IRQ_TYPE_NONE;
426 
427 	port->pirq = pirq;
428 	pirq->irqchip.name = DWAPB_DRIVER_NAME;
429 	pirq->irqchip.irq_ack = dwapb_irq_ack;
430 	pirq->irqchip.irq_mask = dwapb_irq_mask;
431 	pirq->irqchip.irq_unmask = dwapb_irq_unmask;
432 	pirq->irqchip.irq_set_type = dwapb_irq_set_type;
433 	pirq->irqchip.irq_enable = dwapb_irq_enable;
434 	pirq->irqchip.irq_disable = dwapb_irq_disable;
435 #ifdef CONFIG_PM_SLEEP
436 	pirq->irqchip.irq_set_wake = dwapb_irq_set_wake;
437 #endif
438 
439 	if (!pp->irq_shared) {
440 		girq->num_parents = pirq->nr_irqs;
441 		girq->parents = pirq->irq;
442 		girq->parent_handler_data = gpio;
443 		girq->parent_handler = dwapb_irq_handler;
444 	} else {
445 		/* This will let us handle the parent IRQ in the driver */
446 		girq->num_parents = 0;
447 		girq->parents = NULL;
448 		girq->parent_handler = NULL;
449 
450 		/*
451 		 * Request a shared IRQ since where MFD would have devices
452 		 * using the same irq pin
453 		 */
454 		err = devm_request_irq(gpio->dev, pp->irq[0],
455 				       dwapb_irq_handler_mfd,
456 				       IRQF_SHARED, DWAPB_DRIVER_NAME, gpio);
457 		if (err) {
458 			dev_err(gpio->dev, "error requesting IRQ\n");
459 			goto err_kfree_pirq;
460 		}
461 	}
462 
463 	girq->chip = &pirq->irqchip;
464 
465 	return;
466 
467 err_kfree_pirq:
468 	devm_kfree(gpio->dev, pirq);
469 }
470 
471 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
472 			       struct dwapb_port_property *pp,
473 			       unsigned int offs)
474 {
475 	struct dwapb_gpio_port *port;
476 	void __iomem *dat, *set, *dirout;
477 	int err;
478 
479 	port = &gpio->ports[offs];
480 	port->gpio = gpio;
481 	port->idx = pp->idx;
482 
483 #ifdef CONFIG_PM_SLEEP
484 	port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL);
485 	if (!port->ctx)
486 		return -ENOMEM;
487 #endif
488 
489 	dat = gpio->regs + GPIO_EXT_PORTA + pp->idx * GPIO_EXT_PORT_STRIDE;
490 	set = gpio->regs + GPIO_SWPORTA_DR + pp->idx * GPIO_SWPORT_DR_STRIDE;
491 	dirout = gpio->regs + GPIO_SWPORTA_DDR + pp->idx * GPIO_SWPORT_DDR_STRIDE;
492 
493 	/* This registers 32 GPIO lines per port */
494 	err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
495 			 NULL, 0);
496 	if (err) {
497 		dev_err(gpio->dev, "failed to init gpio chip for port%d\n",
498 			port->idx);
499 		return err;
500 	}
501 
502 #ifdef CONFIG_OF_GPIO
503 	port->gc.of_node = to_of_node(pp->fwnode);
504 #endif
505 	port->gc.ngpio = pp->ngpio;
506 	port->gc.base = pp->gpio_base;
507 
508 	/* Only port A support debounce */
509 	if (pp->idx == 0)
510 		port->gc.set_config = dwapb_gpio_set_config;
511 
512 	/* Only port A can provide interrupts in all configurations of the IP */
513 	if (pp->idx == 0)
514 		dwapb_configure_irqs(gpio, port, pp);
515 
516 	err = devm_gpiochip_add_data(gpio->dev, &port->gc, port);
517 	if (err) {
518 		dev_err(gpio->dev, "failed to register gpiochip for port%d\n",
519 			port->idx);
520 		return err;
521 	}
522 
523 	return 0;
524 }
525 
526 static void dwapb_get_irq(struct device *dev, struct fwnode_handle *fwnode,
527 			  struct dwapb_port_property *pp)
528 {
529 	int irq, j;
530 
531 	for (j = 0; j < pp->ngpio; j++) {
532 		if (has_acpi_companion(dev))
533 			irq = platform_get_irq_optional(to_platform_device(dev), j);
534 		else
535 			irq = fwnode_irq_get(fwnode, j);
536 		if (irq > 0)
537 			pp->irq[j] = irq;
538 	}
539 }
540 
541 static struct dwapb_platform_data *dwapb_gpio_get_pdata(struct device *dev)
542 {
543 	struct fwnode_handle *fwnode;
544 	struct dwapb_platform_data *pdata;
545 	struct dwapb_port_property *pp;
546 	int nports;
547 	int i;
548 
549 	nports = device_get_child_node_count(dev);
550 	if (nports == 0)
551 		return ERR_PTR(-ENODEV);
552 
553 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
554 	if (!pdata)
555 		return ERR_PTR(-ENOMEM);
556 
557 	pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL);
558 	if (!pdata->properties)
559 		return ERR_PTR(-ENOMEM);
560 
561 	pdata->nports = nports;
562 
563 	i = 0;
564 	device_for_each_child_node(dev, fwnode)  {
565 		pp = &pdata->properties[i++];
566 		pp->fwnode = fwnode;
567 
568 		if (fwnode_property_read_u32(fwnode, "reg", &pp->idx) ||
569 		    pp->idx >= DWAPB_MAX_PORTS) {
570 			dev_err(dev,
571 				"missing/invalid port index for port%d\n", i);
572 			fwnode_handle_put(fwnode);
573 			return ERR_PTR(-EINVAL);
574 		}
575 
576 		if (fwnode_property_read_u32(fwnode, "ngpios", &pp->ngpio) &&
577 		    fwnode_property_read_u32(fwnode, "snps,nr-gpios", &pp->ngpio)) {
578 			dev_info(dev,
579 				 "failed to get number of gpios for port%d\n",
580 				 i);
581 			pp->ngpio = DWAPB_MAX_GPIOS;
582 		}
583 
584 		pp->irq_shared	= false;
585 		pp->gpio_base	= -1;
586 
587 		/*
588 		 * Only port A can provide interrupts in all configurations of
589 		 * the IP.
590 		 */
591 		if (pp->idx == 0)
592 			dwapb_get_irq(dev, fwnode, pp);
593 	}
594 
595 	return pdata;
596 }
597 
598 static void dwapb_assert_reset(void *data)
599 {
600 	struct dwapb_gpio *gpio = data;
601 
602 	reset_control_assert(gpio->rst);
603 }
604 
605 static int dwapb_get_reset(struct dwapb_gpio *gpio)
606 {
607 	int err;
608 
609 	gpio->rst = devm_reset_control_get_optional_shared(gpio->dev, NULL);
610 	if (IS_ERR(gpio->rst))
611 		return dev_err_probe(gpio->dev, PTR_ERR(gpio->rst),
612 				     "Cannot get reset descriptor\n");
613 
614 	err = reset_control_deassert(gpio->rst);
615 	if (err) {
616 		dev_err(gpio->dev, "Cannot deassert reset lane\n");
617 		return err;
618 	}
619 
620 	return devm_add_action_or_reset(gpio->dev, dwapb_assert_reset, gpio);
621 }
622 
623 static void dwapb_disable_clks(void *data)
624 {
625 	struct dwapb_gpio *gpio = data;
626 
627 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
628 }
629 
630 static int dwapb_get_clks(struct dwapb_gpio *gpio)
631 {
632 	int err;
633 
634 	/* Optional bus and debounce clocks */
635 	gpio->clks[0].id = "bus";
636 	gpio->clks[1].id = "db";
637 	err = devm_clk_bulk_get_optional(gpio->dev, DWAPB_NR_CLOCKS,
638 					 gpio->clks);
639 	if (err) {
640 		dev_err(gpio->dev, "Cannot get APB/Debounce clocks\n");
641 		return err;
642 	}
643 
644 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
645 	if (err) {
646 		dev_err(gpio->dev, "Cannot enable APB/Debounce clocks\n");
647 		return err;
648 	}
649 
650 	return devm_add_action_or_reset(gpio->dev, dwapb_disable_clks, gpio);
651 }
652 
653 static const struct of_device_id dwapb_of_match[] = {
654 	{ .compatible = "snps,dw-apb-gpio", .data = (void *)0},
655 	{ .compatible = "apm,xgene-gpio-v2", .data = (void *)GPIO_REG_OFFSET_V2},
656 	{ /* Sentinel */ }
657 };
658 MODULE_DEVICE_TABLE(of, dwapb_of_match);
659 
660 static const struct acpi_device_id dwapb_acpi_match[] = {
661 	{"HISI0181", 0},
662 	{"APMC0D07", 0},
663 	{"APMC0D81", GPIO_REG_OFFSET_V2},
664 	{ }
665 };
666 MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
667 
668 static int dwapb_gpio_probe(struct platform_device *pdev)
669 {
670 	unsigned int i;
671 	struct dwapb_gpio *gpio;
672 	int err;
673 	struct device *dev = &pdev->dev;
674 	struct dwapb_platform_data *pdata = dev_get_platdata(dev);
675 
676 	if (!pdata) {
677 		pdata = dwapb_gpio_get_pdata(dev);
678 		if (IS_ERR(pdata))
679 			return PTR_ERR(pdata);
680 	}
681 
682 	if (!pdata->nports)
683 		return -ENODEV;
684 
685 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
686 	if (!gpio)
687 		return -ENOMEM;
688 
689 	gpio->dev = &pdev->dev;
690 	gpio->nr_ports = pdata->nports;
691 
692 	err = dwapb_get_reset(gpio);
693 	if (err)
694 		return err;
695 
696 	gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports,
697 				   sizeof(*gpio->ports), GFP_KERNEL);
698 	if (!gpio->ports)
699 		return -ENOMEM;
700 
701 	gpio->regs = devm_platform_ioremap_resource(pdev, 0);
702 	if (IS_ERR(gpio->regs))
703 		return PTR_ERR(gpio->regs);
704 
705 	err = dwapb_get_clks(gpio);
706 	if (err)
707 		return err;
708 
709 	gpio->flags = (uintptr_t)device_get_match_data(dev);
710 
711 	for (i = 0; i < gpio->nr_ports; i++) {
712 		err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
713 		if (err)
714 			return err;
715 	}
716 
717 	platform_set_drvdata(pdev, gpio);
718 
719 	return 0;
720 }
721 
722 #ifdef CONFIG_PM_SLEEP
723 static int dwapb_gpio_suspend(struct device *dev)
724 {
725 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
726 	struct gpio_chip *gc	= &gpio->ports[0].gc;
727 	unsigned long flags;
728 	int i;
729 
730 	spin_lock_irqsave(&gc->bgpio_lock, flags);
731 	for (i = 0; i < gpio->nr_ports; i++) {
732 		unsigned int offset;
733 		unsigned int idx = gpio->ports[i].idx;
734 		struct dwapb_context *ctx = gpio->ports[i].ctx;
735 
736 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
737 		ctx->dir = dwapb_read(gpio, offset);
738 
739 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
740 		ctx->data = dwapb_read(gpio, offset);
741 
742 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
743 		ctx->ext = dwapb_read(gpio, offset);
744 
745 		/* Only port A can provide interrupts */
746 		if (idx == 0) {
747 			ctx->int_mask	= dwapb_read(gpio, GPIO_INTMASK);
748 			ctx->int_en	= dwapb_read(gpio, GPIO_INTEN);
749 			ctx->int_pol	= dwapb_read(gpio, GPIO_INT_POLARITY);
750 			ctx->int_type	= dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
751 			ctx->int_deb	= dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
752 
753 			/* Mask out interrupts */
754 			dwapb_write(gpio, GPIO_INTMASK, ~ctx->wake_en);
755 		}
756 	}
757 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
758 
759 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
760 
761 	return 0;
762 }
763 
764 static int dwapb_gpio_resume(struct device *dev)
765 {
766 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
767 	struct gpio_chip *gc	= &gpio->ports[0].gc;
768 	unsigned long flags;
769 	int i, err;
770 
771 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
772 	if (err) {
773 		dev_err(gpio->dev, "Cannot reenable APB/Debounce clocks\n");
774 		return err;
775 	}
776 
777 	spin_lock_irqsave(&gc->bgpio_lock, flags);
778 	for (i = 0; i < gpio->nr_ports; i++) {
779 		unsigned int offset;
780 		unsigned int idx = gpio->ports[i].idx;
781 		struct dwapb_context *ctx = gpio->ports[i].ctx;
782 
783 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
784 		dwapb_write(gpio, offset, ctx->data);
785 
786 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
787 		dwapb_write(gpio, offset, ctx->dir);
788 
789 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
790 		dwapb_write(gpio, offset, ctx->ext);
791 
792 		/* Only port A can provide interrupts */
793 		if (idx == 0) {
794 			dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
795 			dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
796 			dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
797 			dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
798 			dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask);
799 
800 			/* Clear out spurious interrupts */
801 			dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
802 		}
803 	}
804 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
805 
806 	return 0;
807 }
808 #endif
809 
810 static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
811 			 dwapb_gpio_resume);
812 
813 static struct platform_driver dwapb_gpio_driver = {
814 	.driver		= {
815 		.name	= DWAPB_DRIVER_NAME,
816 		.pm	= &dwapb_gpio_pm_ops,
817 		.of_match_table = dwapb_of_match,
818 		.acpi_match_table = dwapb_acpi_match,
819 	},
820 	.probe		= dwapb_gpio_probe,
821 };
822 
823 module_platform_driver(dwapb_gpio_driver);
824 
825 MODULE_LICENSE("GPL");
826 MODULE_AUTHOR("Jamie Iles");
827 MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
828 MODULE_ALIAS("platform:" DWAPB_DRIVER_NAME);
829