xref: /openbmc/linux/drivers/gpio/gpio-dwapb.c (revision 7bcae826)
1 /*
2  * Copyright (c) 2011 Jamie Iles
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * All enquiries to support@picochip.com
9  */
10 #include <linux/acpi.h>
11 #include <linux/gpio/driver.h>
12 /* FIXME: for gpio_get_value(), replace this with direct register read */
13 #include <linux/gpio.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/ioport.h>
19 #include <linux/irq.h>
20 #include <linux/irqdomain.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/of_irq.h>
25 #include <linux/platform_device.h>
26 #include <linux/property.h>
27 #include <linux/spinlock.h>
28 #include <linux/platform_data/gpio-dwapb.h>
29 #include <linux/slab.h>
30 
31 #include "gpiolib.h"
32 
33 #define GPIO_SWPORTA_DR		0x00
34 #define GPIO_SWPORTA_DDR	0x04
35 #define GPIO_SWPORTB_DR		0x0c
36 #define GPIO_SWPORTB_DDR	0x10
37 #define GPIO_SWPORTC_DR		0x18
38 #define GPIO_SWPORTC_DDR	0x1c
39 #define GPIO_SWPORTD_DR		0x24
40 #define GPIO_SWPORTD_DDR	0x28
41 #define GPIO_INTEN		0x30
42 #define GPIO_INTMASK		0x34
43 #define GPIO_INTTYPE_LEVEL	0x38
44 #define GPIO_INT_POLARITY	0x3c
45 #define GPIO_INTSTATUS		0x40
46 #define GPIO_PORTA_DEBOUNCE	0x48
47 #define GPIO_PORTA_EOI		0x4c
48 #define GPIO_EXT_PORTA		0x50
49 #define GPIO_EXT_PORTB		0x54
50 #define GPIO_EXT_PORTC		0x58
51 #define GPIO_EXT_PORTD		0x5c
52 
53 #define DWAPB_MAX_PORTS		4
54 #define GPIO_EXT_PORT_SIZE	(GPIO_EXT_PORTB - GPIO_EXT_PORTA)
55 #define GPIO_SWPORT_DR_SIZE	(GPIO_SWPORTB_DR - GPIO_SWPORTA_DR)
56 #define GPIO_SWPORT_DDR_SIZE	(GPIO_SWPORTB_DDR - GPIO_SWPORTA_DDR)
57 
58 struct dwapb_gpio;
59 
60 #ifdef CONFIG_PM_SLEEP
61 /* Store GPIO context across system-wide suspend/resume transitions */
62 struct dwapb_context {
63 	u32 data;
64 	u32 dir;
65 	u32 ext;
66 	u32 int_en;
67 	u32 int_mask;
68 	u32 int_type;
69 	u32 int_pol;
70 	u32 int_deb;
71 };
72 #endif
73 
74 struct dwapb_gpio_port {
75 	struct gpio_chip	gc;
76 	bool			is_registered;
77 	struct dwapb_gpio	*gpio;
78 #ifdef CONFIG_PM_SLEEP
79 	struct dwapb_context	*ctx;
80 #endif
81 	unsigned int		idx;
82 };
83 
84 struct dwapb_gpio {
85 	struct	device		*dev;
86 	void __iomem		*regs;
87 	struct dwapb_gpio_port	*ports;
88 	unsigned int		nr_ports;
89 	struct irq_domain	*domain;
90 };
91 
92 static inline u32 dwapb_read(struct dwapb_gpio *gpio, unsigned int offset)
93 {
94 	struct gpio_chip *gc	= &gpio->ports[0].gc;
95 	void __iomem *reg_base	= gpio->regs;
96 
97 	return gc->read_reg(reg_base + offset);
98 }
99 
100 static inline void dwapb_write(struct dwapb_gpio *gpio, unsigned int offset,
101 			       u32 val)
102 {
103 	struct gpio_chip *gc	= &gpio->ports[0].gc;
104 	void __iomem *reg_base	= gpio->regs;
105 
106 	gc->write_reg(reg_base + offset, val);
107 }
108 
109 static int dwapb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
110 {
111 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
112 	struct dwapb_gpio *gpio = port->gpio;
113 
114 	return irq_find_mapping(gpio->domain, offset);
115 }
116 
117 static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
118 {
119 	u32 v = dwapb_read(gpio, GPIO_INT_POLARITY);
120 
121 	if (gpio_get_value(gpio->ports[0].gc.base + offs))
122 		v &= ~BIT(offs);
123 	else
124 		v |= BIT(offs);
125 
126 	dwapb_write(gpio, GPIO_INT_POLARITY, v);
127 }
128 
129 static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
130 {
131 	u32 irq_status = readl_relaxed(gpio->regs + GPIO_INTSTATUS);
132 	u32 ret = irq_status;
133 
134 	while (irq_status) {
135 		int hwirq = fls(irq_status) - 1;
136 		int gpio_irq = irq_find_mapping(gpio->domain, hwirq);
137 
138 		generic_handle_irq(gpio_irq);
139 		irq_status &= ~BIT(hwirq);
140 
141 		if ((irq_get_trigger_type(gpio_irq) & IRQ_TYPE_SENSE_MASK)
142 			== IRQ_TYPE_EDGE_BOTH)
143 			dwapb_toggle_trigger(gpio, hwirq);
144 	}
145 
146 	return ret;
147 }
148 
149 static void dwapb_irq_handler(struct irq_desc *desc)
150 {
151 	struct dwapb_gpio *gpio = irq_desc_get_handler_data(desc);
152 	struct irq_chip *chip = irq_desc_get_chip(desc);
153 
154 	dwapb_do_irq(gpio);
155 
156 	if (chip->irq_eoi)
157 		chip->irq_eoi(irq_desc_get_irq_data(desc));
158 }
159 
160 static void dwapb_irq_enable(struct irq_data *d)
161 {
162 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
163 	struct dwapb_gpio *gpio = igc->private;
164 	struct gpio_chip *gc = &gpio->ports[0].gc;
165 	unsigned long flags;
166 	u32 val;
167 
168 	spin_lock_irqsave(&gc->bgpio_lock, flags);
169 	val = dwapb_read(gpio, GPIO_INTEN);
170 	val |= BIT(d->hwirq);
171 	dwapb_write(gpio, GPIO_INTEN, val);
172 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
173 }
174 
175 static void dwapb_irq_disable(struct irq_data *d)
176 {
177 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
178 	struct dwapb_gpio *gpio = igc->private;
179 	struct gpio_chip *gc = &gpio->ports[0].gc;
180 	unsigned long flags;
181 	u32 val;
182 
183 	spin_lock_irqsave(&gc->bgpio_lock, flags);
184 	val = dwapb_read(gpio, GPIO_INTEN);
185 	val &= ~BIT(d->hwirq);
186 	dwapb_write(gpio, GPIO_INTEN, val);
187 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
188 }
189 
190 static int dwapb_irq_reqres(struct irq_data *d)
191 {
192 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
193 	struct dwapb_gpio *gpio = igc->private;
194 	struct gpio_chip *gc = &gpio->ports[0].gc;
195 
196 	if (gpiochip_lock_as_irq(gc, irqd_to_hwirq(d))) {
197 		dev_err(gpio->dev, "unable to lock HW IRQ %lu for IRQ\n",
198 			irqd_to_hwirq(d));
199 		return -EINVAL;
200 	}
201 	return 0;
202 }
203 
204 static void dwapb_irq_relres(struct irq_data *d)
205 {
206 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
207 	struct dwapb_gpio *gpio = igc->private;
208 	struct gpio_chip *gc = &gpio->ports[0].gc;
209 
210 	gpiochip_unlock_as_irq(gc, irqd_to_hwirq(d));
211 }
212 
213 static int dwapb_irq_set_type(struct irq_data *d, u32 type)
214 {
215 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
216 	struct dwapb_gpio *gpio = igc->private;
217 	struct gpio_chip *gc = &gpio->ports[0].gc;
218 	int bit = d->hwirq;
219 	unsigned long level, polarity, flags;
220 
221 	if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING |
222 		     IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
223 		return -EINVAL;
224 
225 	spin_lock_irqsave(&gc->bgpio_lock, flags);
226 	level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
227 	polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
228 
229 	switch (type) {
230 	case IRQ_TYPE_EDGE_BOTH:
231 		level |= BIT(bit);
232 		dwapb_toggle_trigger(gpio, bit);
233 		break;
234 	case IRQ_TYPE_EDGE_RISING:
235 		level |= BIT(bit);
236 		polarity |= BIT(bit);
237 		break;
238 	case IRQ_TYPE_EDGE_FALLING:
239 		level |= BIT(bit);
240 		polarity &= ~BIT(bit);
241 		break;
242 	case IRQ_TYPE_LEVEL_HIGH:
243 		level &= ~BIT(bit);
244 		polarity |= BIT(bit);
245 		break;
246 	case IRQ_TYPE_LEVEL_LOW:
247 		level &= ~BIT(bit);
248 		polarity &= ~BIT(bit);
249 		break;
250 	}
251 
252 	irq_setup_alt_chip(d, type);
253 
254 	dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level);
255 	dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
256 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
257 
258 	return 0;
259 }
260 
261 static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
262 				   unsigned offset, unsigned debounce)
263 {
264 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
265 	struct dwapb_gpio *gpio = port->gpio;
266 	unsigned long flags, val_deb;
267 	unsigned long mask = gc->pin2mask(gc, offset);
268 
269 	spin_lock_irqsave(&gc->bgpio_lock, flags);
270 
271 	val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
272 	if (debounce)
273 		dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb | mask);
274 	else
275 		dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb & ~mask);
276 
277 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
278 
279 	return 0;
280 }
281 
282 static int dwapb_gpio_set_config(struct gpio_chip *gc, unsigned offset,
283 				 unsigned long config)
284 {
285 	u32 debounce;
286 
287 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
288 		return -ENOTSUPP;
289 
290 	debounce = pinconf_to_config_argument(config);
291 	return dwapb_gpio_set_debounce(gc, offset, debounce);
292 }
293 
294 static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id)
295 {
296 	u32 worked;
297 	struct dwapb_gpio *gpio = dev_id;
298 
299 	worked = dwapb_do_irq(gpio);
300 
301 	return worked ? IRQ_HANDLED : IRQ_NONE;
302 }
303 
304 static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
305 				 struct dwapb_gpio_port *port,
306 				 struct dwapb_port_property *pp)
307 {
308 	struct gpio_chip *gc = &port->gc;
309 	struct fwnode_handle  *fwnode = pp->fwnode;
310 	struct irq_chip_generic	*irq_gc = NULL;
311 	unsigned int hwirq, ngpio = gc->ngpio;
312 	struct irq_chip_type *ct;
313 	int err, i;
314 
315 	gpio->domain = irq_domain_create_linear(fwnode, ngpio,
316 						 &irq_generic_chip_ops, gpio);
317 	if (!gpio->domain)
318 		return;
319 
320 	err = irq_alloc_domain_generic_chips(gpio->domain, ngpio, 2,
321 					     "gpio-dwapb", handle_level_irq,
322 					     IRQ_NOREQUEST, 0,
323 					     IRQ_GC_INIT_NESTED_LOCK);
324 	if (err) {
325 		dev_info(gpio->dev, "irq_alloc_domain_generic_chips failed\n");
326 		irq_domain_remove(gpio->domain);
327 		gpio->domain = NULL;
328 		return;
329 	}
330 
331 	irq_gc = irq_get_domain_generic_chip(gpio->domain, 0);
332 	if (!irq_gc) {
333 		irq_domain_remove(gpio->domain);
334 		gpio->domain = NULL;
335 		return;
336 	}
337 
338 	irq_gc->reg_base = gpio->regs;
339 	irq_gc->private = gpio;
340 
341 	for (i = 0; i < 2; i++) {
342 		ct = &irq_gc->chip_types[i];
343 		ct->chip.irq_ack = irq_gc_ack_set_bit;
344 		ct->chip.irq_mask = irq_gc_mask_set_bit;
345 		ct->chip.irq_unmask = irq_gc_mask_clr_bit;
346 		ct->chip.irq_set_type = dwapb_irq_set_type;
347 		ct->chip.irq_enable = dwapb_irq_enable;
348 		ct->chip.irq_disable = dwapb_irq_disable;
349 		ct->chip.irq_request_resources = dwapb_irq_reqres;
350 		ct->chip.irq_release_resources = dwapb_irq_relres;
351 		ct->regs.ack = GPIO_PORTA_EOI;
352 		ct->regs.mask = GPIO_INTMASK;
353 		ct->type = IRQ_TYPE_LEVEL_MASK;
354 	}
355 
356 	irq_gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK;
357 	irq_gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH;
358 	irq_gc->chip_types[1].handler = handle_edge_irq;
359 
360 	if (!pp->irq_shared) {
361 		irq_set_chained_handler_and_data(pp->irq, dwapb_irq_handler,
362 						 gpio);
363 	} else {
364 		/*
365 		 * Request a shared IRQ since where MFD would have devices
366 		 * using the same irq pin
367 		 */
368 		err = devm_request_irq(gpio->dev, pp->irq,
369 				       dwapb_irq_handler_mfd,
370 				       IRQF_SHARED, "gpio-dwapb-mfd", gpio);
371 		if (err) {
372 			dev_err(gpio->dev, "error requesting IRQ\n");
373 			irq_domain_remove(gpio->domain);
374 			gpio->domain = NULL;
375 			return;
376 		}
377 	}
378 
379 	for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
380 		irq_create_mapping(gpio->domain, hwirq);
381 
382 	port->gc.to_irq = dwapb_gpio_to_irq;
383 }
384 
385 static void dwapb_irq_teardown(struct dwapb_gpio *gpio)
386 {
387 	struct dwapb_gpio_port *port = &gpio->ports[0];
388 	struct gpio_chip *gc = &port->gc;
389 	unsigned int ngpio = gc->ngpio;
390 	irq_hw_number_t hwirq;
391 
392 	if (!gpio->domain)
393 		return;
394 
395 	for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
396 		irq_dispose_mapping(irq_find_mapping(gpio->domain, hwirq));
397 
398 	irq_domain_remove(gpio->domain);
399 	gpio->domain = NULL;
400 }
401 
402 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
403 			       struct dwapb_port_property *pp,
404 			       unsigned int offs)
405 {
406 	struct dwapb_gpio_port *port;
407 	void __iomem *dat, *set, *dirout;
408 	int err;
409 
410 	port = &gpio->ports[offs];
411 	port->gpio = gpio;
412 	port->idx = pp->idx;
413 
414 #ifdef CONFIG_PM_SLEEP
415 	port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL);
416 	if (!port->ctx)
417 		return -ENOMEM;
418 #endif
419 
420 	dat = gpio->regs + GPIO_EXT_PORTA + (pp->idx * GPIO_EXT_PORT_SIZE);
421 	set = gpio->regs + GPIO_SWPORTA_DR + (pp->idx * GPIO_SWPORT_DR_SIZE);
422 	dirout = gpio->regs + GPIO_SWPORTA_DDR +
423 		(pp->idx * GPIO_SWPORT_DDR_SIZE);
424 
425 	err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
426 			 NULL, false);
427 	if (err) {
428 		dev_err(gpio->dev, "failed to init gpio chip for port%d\n",
429 			port->idx);
430 		return err;
431 	}
432 
433 #ifdef CONFIG_OF_GPIO
434 	port->gc.of_node = to_of_node(pp->fwnode);
435 #endif
436 	port->gc.ngpio = pp->ngpio;
437 	port->gc.base = pp->gpio_base;
438 
439 	/* Only port A support debounce */
440 	if (pp->idx == 0)
441 		port->gc.set_config = dwapb_gpio_set_config;
442 
443 	if (pp->irq)
444 		dwapb_configure_irqs(gpio, port, pp);
445 
446 	err = gpiochip_add_data(&port->gc, port);
447 	if (err)
448 		dev_err(gpio->dev, "failed to register gpiochip for port%d\n",
449 			port->idx);
450 	else
451 		port->is_registered = true;
452 
453 	/* Add GPIO-signaled ACPI event support */
454 	if (pp->irq)
455 		acpi_gpiochip_request_interrupts(&port->gc);
456 
457 	return err;
458 }
459 
460 static void dwapb_gpio_unregister(struct dwapb_gpio *gpio)
461 {
462 	unsigned int m;
463 
464 	for (m = 0; m < gpio->nr_ports; ++m)
465 		if (gpio->ports[m].is_registered)
466 			gpiochip_remove(&gpio->ports[m].gc);
467 }
468 
469 static struct dwapb_platform_data *
470 dwapb_gpio_get_pdata(struct device *dev)
471 {
472 	struct fwnode_handle *fwnode;
473 	struct dwapb_platform_data *pdata;
474 	struct dwapb_port_property *pp;
475 	int nports;
476 	int i;
477 
478 	nports = device_get_child_node_count(dev);
479 	if (nports == 0)
480 		return ERR_PTR(-ENODEV);
481 
482 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
483 	if (!pdata)
484 		return ERR_PTR(-ENOMEM);
485 
486 	pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL);
487 	if (!pdata->properties)
488 		return ERR_PTR(-ENOMEM);
489 
490 	pdata->nports = nports;
491 
492 	i = 0;
493 	device_for_each_child_node(dev, fwnode)  {
494 		pp = &pdata->properties[i++];
495 		pp->fwnode = fwnode;
496 
497 		if (fwnode_property_read_u32(fwnode, "reg", &pp->idx) ||
498 		    pp->idx >= DWAPB_MAX_PORTS) {
499 			dev_err(dev,
500 				"missing/invalid port index for port%d\n", i);
501 			fwnode_handle_put(fwnode);
502 			return ERR_PTR(-EINVAL);
503 		}
504 
505 		if (fwnode_property_read_u32(fwnode, "snps,nr-gpios",
506 					 &pp->ngpio)) {
507 			dev_info(dev,
508 				 "failed to get number of gpios for port%d\n",
509 				 i);
510 			pp->ngpio = 32;
511 		}
512 
513 		/*
514 		 * Only port A can provide interrupts in all configurations of
515 		 * the IP.
516 		 */
517 		if (dev->of_node && pp->idx == 0 &&
518 			fwnode_property_read_bool(fwnode,
519 						  "interrupt-controller")) {
520 			pp->irq = irq_of_parse_and_map(to_of_node(fwnode), 0);
521 			if (!pp->irq)
522 				dev_warn(dev, "no irq for port%d\n", pp->idx);
523 		}
524 
525 		if (has_acpi_companion(dev) && pp->idx == 0)
526 			pp->irq = platform_get_irq(to_platform_device(dev), 0);
527 
528 		pp->irq_shared	= false;
529 		pp->gpio_base	= -1;
530 	}
531 
532 	return pdata;
533 }
534 
535 static int dwapb_gpio_probe(struct platform_device *pdev)
536 {
537 	unsigned int i;
538 	struct resource *res;
539 	struct dwapb_gpio *gpio;
540 	int err;
541 	struct device *dev = &pdev->dev;
542 	struct dwapb_platform_data *pdata = dev_get_platdata(dev);
543 
544 	if (!pdata) {
545 		pdata = dwapb_gpio_get_pdata(dev);
546 		if (IS_ERR(pdata))
547 			return PTR_ERR(pdata);
548 	}
549 
550 	if (!pdata->nports)
551 		return -ENODEV;
552 
553 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
554 	if (!gpio)
555 		return -ENOMEM;
556 
557 	gpio->dev = &pdev->dev;
558 	gpio->nr_ports = pdata->nports;
559 
560 	gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports,
561 				   sizeof(*gpio->ports), GFP_KERNEL);
562 	if (!gpio->ports)
563 		return -ENOMEM;
564 
565 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
566 	gpio->regs = devm_ioremap_resource(&pdev->dev, res);
567 	if (IS_ERR(gpio->regs))
568 		return PTR_ERR(gpio->regs);
569 
570 	for (i = 0; i < gpio->nr_ports; i++) {
571 		err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
572 		if (err)
573 			goto out_unregister;
574 	}
575 	platform_set_drvdata(pdev, gpio);
576 
577 	return 0;
578 
579 out_unregister:
580 	dwapb_gpio_unregister(gpio);
581 	dwapb_irq_teardown(gpio);
582 
583 	return err;
584 }
585 
586 static int dwapb_gpio_remove(struct platform_device *pdev)
587 {
588 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
589 
590 	dwapb_gpio_unregister(gpio);
591 	dwapb_irq_teardown(gpio);
592 
593 	return 0;
594 }
595 
596 static const struct of_device_id dwapb_of_match[] = {
597 	{ .compatible = "snps,dw-apb-gpio" },
598 	{ /* Sentinel */ }
599 };
600 MODULE_DEVICE_TABLE(of, dwapb_of_match);
601 
602 static const struct acpi_device_id dwapb_acpi_match[] = {
603 	{"HISI0181", 0},
604 	{"APMC0D07", 0},
605 	{ }
606 };
607 MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
608 
609 #ifdef CONFIG_PM_SLEEP
610 static int dwapb_gpio_suspend(struct device *dev)
611 {
612 	struct platform_device *pdev = to_platform_device(dev);
613 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
614 	struct gpio_chip *gc	= &gpio->ports[0].gc;
615 	unsigned long flags;
616 	int i;
617 
618 	spin_lock_irqsave(&gc->bgpio_lock, flags);
619 	for (i = 0; i < gpio->nr_ports; i++) {
620 		unsigned int offset;
621 		unsigned int idx = gpio->ports[i].idx;
622 		struct dwapb_context *ctx = gpio->ports[i].ctx;
623 
624 		BUG_ON(!ctx);
625 
626 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_SIZE;
627 		ctx->dir = dwapb_read(gpio, offset);
628 
629 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_SIZE;
630 		ctx->data = dwapb_read(gpio, offset);
631 
632 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_SIZE;
633 		ctx->ext = dwapb_read(gpio, offset);
634 
635 		/* Only port A can provide interrupts */
636 		if (idx == 0) {
637 			ctx->int_mask	= dwapb_read(gpio, GPIO_INTMASK);
638 			ctx->int_en	= dwapb_read(gpio, GPIO_INTEN);
639 			ctx->int_pol	= dwapb_read(gpio, GPIO_INT_POLARITY);
640 			ctx->int_type	= dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
641 			ctx->int_deb	= dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
642 
643 			/* Mask out interrupts */
644 			dwapb_write(gpio, GPIO_INTMASK, 0xffffffff);
645 		}
646 	}
647 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
648 
649 	return 0;
650 }
651 
652 static int dwapb_gpio_resume(struct device *dev)
653 {
654 	struct platform_device *pdev = to_platform_device(dev);
655 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
656 	struct gpio_chip *gc	= &gpio->ports[0].gc;
657 	unsigned long flags;
658 	int i;
659 
660 	spin_lock_irqsave(&gc->bgpio_lock, flags);
661 	for (i = 0; i < gpio->nr_ports; i++) {
662 		unsigned int offset;
663 		unsigned int idx = gpio->ports[i].idx;
664 		struct dwapb_context *ctx = gpio->ports[i].ctx;
665 
666 		BUG_ON(!ctx);
667 
668 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_SIZE;
669 		dwapb_write(gpio, offset, ctx->data);
670 
671 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_SIZE;
672 		dwapb_write(gpio, offset, ctx->dir);
673 
674 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_SIZE;
675 		dwapb_write(gpio, offset, ctx->ext);
676 
677 		/* Only port A can provide interrupts */
678 		if (idx == 0) {
679 			dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
680 			dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
681 			dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
682 			dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
683 			dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask);
684 
685 			/* Clear out spurious interrupts */
686 			dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
687 		}
688 	}
689 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
690 
691 	return 0;
692 }
693 #endif
694 
695 static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
696 			 dwapb_gpio_resume);
697 
698 static struct platform_driver dwapb_gpio_driver = {
699 	.driver		= {
700 		.name	= "gpio-dwapb",
701 		.pm	= &dwapb_gpio_pm_ops,
702 		.of_match_table = of_match_ptr(dwapb_of_match),
703 		.acpi_match_table = ACPI_PTR(dwapb_acpi_match),
704 	},
705 	.probe		= dwapb_gpio_probe,
706 	.remove		= dwapb_gpio_remove,
707 };
708 
709 module_platform_driver(dwapb_gpio_driver);
710 
711 MODULE_LICENSE("GPL");
712 MODULE_AUTHOR("Jamie Iles");
713 MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
714