xref: /openbmc/linux/drivers/gpio/gpio-dwapb.c (revision 65417d9f)
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_device.h>
25 #include <linux/of_irq.h>
26 #include <linux/platform_device.h>
27 #include <linux/property.h>
28 #include <linux/reset.h>
29 #include <linux/spinlock.h>
30 #include <linux/platform_data/gpio-dwapb.h>
31 #include <linux/slab.h>
32 
33 #include "gpiolib.h"
34 
35 #define GPIO_SWPORTA_DR		0x00
36 #define GPIO_SWPORTA_DDR	0x04
37 #define GPIO_SWPORTB_DR		0x0c
38 #define GPIO_SWPORTB_DDR	0x10
39 #define GPIO_SWPORTC_DR		0x18
40 #define GPIO_SWPORTC_DDR	0x1c
41 #define GPIO_SWPORTD_DR		0x24
42 #define GPIO_SWPORTD_DDR	0x28
43 #define GPIO_INTEN		0x30
44 #define GPIO_INTMASK		0x34
45 #define GPIO_INTTYPE_LEVEL	0x38
46 #define GPIO_INT_POLARITY	0x3c
47 #define GPIO_INTSTATUS		0x40
48 #define GPIO_PORTA_DEBOUNCE	0x48
49 #define GPIO_PORTA_EOI		0x4c
50 #define GPIO_EXT_PORTA		0x50
51 #define GPIO_EXT_PORTB		0x54
52 #define GPIO_EXT_PORTC		0x58
53 #define GPIO_EXT_PORTD		0x5c
54 
55 #define DWAPB_MAX_PORTS		4
56 #define GPIO_EXT_PORT_SIZE	(GPIO_EXT_PORTB - GPIO_EXT_PORTA)
57 #define GPIO_SWPORT_DR_SIZE	(GPIO_SWPORTB_DR - GPIO_SWPORTA_DR)
58 #define GPIO_SWPORT_DDR_SIZE	(GPIO_SWPORTB_DDR - GPIO_SWPORTA_DDR)
59 
60 #define GPIO_REG_OFFSET_V2	1
61 
62 #define GPIO_INTMASK_V2		0x44
63 #define GPIO_INTTYPE_LEVEL_V2	0x34
64 #define GPIO_INT_POLARITY_V2	0x38
65 #define GPIO_INTSTATUS_V2	0x3c
66 #define GPIO_PORTA_EOI_V2	0x40
67 
68 struct dwapb_gpio;
69 
70 #ifdef CONFIG_PM_SLEEP
71 /* Store GPIO context across system-wide suspend/resume transitions */
72 struct dwapb_context {
73 	u32 data;
74 	u32 dir;
75 	u32 ext;
76 	u32 int_en;
77 	u32 int_mask;
78 	u32 int_type;
79 	u32 int_pol;
80 	u32 int_deb;
81 	u32 wake_en;
82 };
83 #endif
84 
85 struct dwapb_gpio_port {
86 	struct gpio_chip	gc;
87 	bool			is_registered;
88 	struct dwapb_gpio	*gpio;
89 #ifdef CONFIG_PM_SLEEP
90 	struct dwapb_context	*ctx;
91 #endif
92 	unsigned int		idx;
93 };
94 
95 struct dwapb_gpio {
96 	struct	device		*dev;
97 	void __iomem		*regs;
98 	struct dwapb_gpio_port	*ports;
99 	unsigned int		nr_ports;
100 	struct irq_domain	*domain;
101 	unsigned int		flags;
102 	struct reset_control	*rst;
103 };
104 
105 static inline u32 gpio_reg_v2_convert(unsigned int offset)
106 {
107 	switch (offset) {
108 	case GPIO_INTMASK:
109 		return GPIO_INTMASK_V2;
110 	case GPIO_INTTYPE_LEVEL:
111 		return GPIO_INTTYPE_LEVEL_V2;
112 	case GPIO_INT_POLARITY:
113 		return GPIO_INT_POLARITY_V2;
114 	case GPIO_INTSTATUS:
115 		return GPIO_INTSTATUS_V2;
116 	case GPIO_PORTA_EOI:
117 		return GPIO_PORTA_EOI_V2;
118 	}
119 
120 	return offset;
121 }
122 
123 static inline u32 gpio_reg_convert(struct dwapb_gpio *gpio, unsigned int offset)
124 {
125 	if (gpio->flags & GPIO_REG_OFFSET_V2)
126 		return gpio_reg_v2_convert(offset);
127 
128 	return offset;
129 }
130 
131 static inline u32 dwapb_read(struct dwapb_gpio *gpio, unsigned int offset)
132 {
133 	struct gpio_chip *gc	= &gpio->ports[0].gc;
134 	void __iomem *reg_base	= gpio->regs;
135 
136 	return gc->read_reg(reg_base + gpio_reg_convert(gpio, offset));
137 }
138 
139 static inline void dwapb_write(struct dwapb_gpio *gpio, unsigned int offset,
140 			       u32 val)
141 {
142 	struct gpio_chip *gc	= &gpio->ports[0].gc;
143 	void __iomem *reg_base	= gpio->regs;
144 
145 	gc->write_reg(reg_base + gpio_reg_convert(gpio, offset), val);
146 }
147 
148 static int dwapb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
149 {
150 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
151 	struct dwapb_gpio *gpio = port->gpio;
152 
153 	return irq_find_mapping(gpio->domain, offset);
154 }
155 
156 static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
157 {
158 	u32 v = dwapb_read(gpio, GPIO_INT_POLARITY);
159 
160 	if (gpio_get_value(gpio->ports[0].gc.base + offs))
161 		v &= ~BIT(offs);
162 	else
163 		v |= BIT(offs);
164 
165 	dwapb_write(gpio, GPIO_INT_POLARITY, v);
166 }
167 
168 static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
169 {
170 	u32 irq_status = dwapb_read(gpio, GPIO_INTSTATUS);
171 	u32 ret = irq_status;
172 
173 	while (irq_status) {
174 		int hwirq = fls(irq_status) - 1;
175 		int gpio_irq = irq_find_mapping(gpio->domain, hwirq);
176 
177 		generic_handle_irq(gpio_irq);
178 		irq_status &= ~BIT(hwirq);
179 
180 		if ((irq_get_trigger_type(gpio_irq) & IRQ_TYPE_SENSE_MASK)
181 			== IRQ_TYPE_EDGE_BOTH)
182 			dwapb_toggle_trigger(gpio, hwirq);
183 	}
184 
185 	return ret;
186 }
187 
188 static void dwapb_irq_handler(struct irq_desc *desc)
189 {
190 	struct dwapb_gpio *gpio = irq_desc_get_handler_data(desc);
191 	struct irq_chip *chip = irq_desc_get_chip(desc);
192 
193 	dwapb_do_irq(gpio);
194 
195 	if (chip->irq_eoi)
196 		chip->irq_eoi(irq_desc_get_irq_data(desc));
197 }
198 
199 static void dwapb_irq_enable(struct irq_data *d)
200 {
201 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
202 	struct dwapb_gpio *gpio = igc->private;
203 	struct gpio_chip *gc = &gpio->ports[0].gc;
204 	unsigned long flags;
205 	u32 val;
206 
207 	spin_lock_irqsave(&gc->bgpio_lock, flags);
208 	val = dwapb_read(gpio, GPIO_INTEN);
209 	val |= BIT(d->hwirq);
210 	dwapb_write(gpio, GPIO_INTEN, val);
211 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
212 }
213 
214 static void dwapb_irq_disable(struct irq_data *d)
215 {
216 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
217 	struct dwapb_gpio *gpio = igc->private;
218 	struct gpio_chip *gc = &gpio->ports[0].gc;
219 	unsigned long flags;
220 	u32 val;
221 
222 	spin_lock_irqsave(&gc->bgpio_lock, flags);
223 	val = dwapb_read(gpio, GPIO_INTEN);
224 	val &= ~BIT(d->hwirq);
225 	dwapb_write(gpio, GPIO_INTEN, val);
226 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
227 }
228 
229 static int dwapb_irq_reqres(struct irq_data *d)
230 {
231 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
232 	struct dwapb_gpio *gpio = igc->private;
233 	struct gpio_chip *gc = &gpio->ports[0].gc;
234 
235 	if (gpiochip_lock_as_irq(gc, irqd_to_hwirq(d))) {
236 		dev_err(gpio->dev, "unable to lock HW IRQ %lu for IRQ\n",
237 			irqd_to_hwirq(d));
238 		return -EINVAL;
239 	}
240 	return 0;
241 }
242 
243 static void dwapb_irq_relres(struct irq_data *d)
244 {
245 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
246 	struct dwapb_gpio *gpio = igc->private;
247 	struct gpio_chip *gc = &gpio->ports[0].gc;
248 
249 	gpiochip_unlock_as_irq(gc, irqd_to_hwirq(d));
250 }
251 
252 static int dwapb_irq_set_type(struct irq_data *d, u32 type)
253 {
254 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
255 	struct dwapb_gpio *gpio = igc->private;
256 	struct gpio_chip *gc = &gpio->ports[0].gc;
257 	int bit = d->hwirq;
258 	unsigned long level, polarity, flags;
259 
260 	if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING |
261 		     IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
262 		return -EINVAL;
263 
264 	spin_lock_irqsave(&gc->bgpio_lock, flags);
265 	level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
266 	polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
267 
268 	switch (type) {
269 	case IRQ_TYPE_EDGE_BOTH:
270 		level |= BIT(bit);
271 		dwapb_toggle_trigger(gpio, bit);
272 		break;
273 	case IRQ_TYPE_EDGE_RISING:
274 		level |= BIT(bit);
275 		polarity |= BIT(bit);
276 		break;
277 	case IRQ_TYPE_EDGE_FALLING:
278 		level |= BIT(bit);
279 		polarity &= ~BIT(bit);
280 		break;
281 	case IRQ_TYPE_LEVEL_HIGH:
282 		level &= ~BIT(bit);
283 		polarity |= BIT(bit);
284 		break;
285 	case IRQ_TYPE_LEVEL_LOW:
286 		level &= ~BIT(bit);
287 		polarity &= ~BIT(bit);
288 		break;
289 	}
290 
291 	irq_setup_alt_chip(d, type);
292 
293 	dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level);
294 	if (type != IRQ_TYPE_EDGE_BOTH)
295 		dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
296 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
297 
298 	return 0;
299 }
300 
301 #ifdef CONFIG_PM_SLEEP
302 static int dwapb_irq_set_wake(struct irq_data *d, unsigned int enable)
303 {
304 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
305 	struct dwapb_gpio *gpio = igc->private;
306 	struct dwapb_context *ctx = gpio->ports[0].ctx;
307 
308 	if (enable)
309 		ctx->wake_en |= BIT(d->hwirq);
310 	else
311 		ctx->wake_en &= ~BIT(d->hwirq);
312 
313 	return 0;
314 }
315 #endif
316 
317 static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
318 				   unsigned offset, unsigned debounce)
319 {
320 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
321 	struct dwapb_gpio *gpio = port->gpio;
322 	unsigned long flags, val_deb;
323 	unsigned long mask = BIT(offset);
324 
325 	spin_lock_irqsave(&gc->bgpio_lock, flags);
326 
327 	val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
328 	if (debounce)
329 		dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb | mask);
330 	else
331 		dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb & ~mask);
332 
333 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
334 
335 	return 0;
336 }
337 
338 static int dwapb_gpio_set_config(struct gpio_chip *gc, unsigned offset,
339 				 unsigned long config)
340 {
341 	u32 debounce;
342 
343 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
344 		return -ENOTSUPP;
345 
346 	debounce = pinconf_to_config_argument(config);
347 	return dwapb_gpio_set_debounce(gc, offset, debounce);
348 }
349 
350 static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id)
351 {
352 	u32 worked;
353 	struct dwapb_gpio *gpio = dev_id;
354 
355 	worked = dwapb_do_irq(gpio);
356 
357 	return worked ? IRQ_HANDLED : IRQ_NONE;
358 }
359 
360 static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
361 				 struct dwapb_gpio_port *port,
362 				 struct dwapb_port_property *pp)
363 {
364 	struct gpio_chip *gc = &port->gc;
365 	struct fwnode_handle  *fwnode = pp->fwnode;
366 	struct irq_chip_generic	*irq_gc = NULL;
367 	unsigned int hwirq, ngpio = gc->ngpio;
368 	struct irq_chip_type *ct;
369 	int err, i;
370 
371 	gpio->domain = irq_domain_create_linear(fwnode, ngpio,
372 						 &irq_generic_chip_ops, gpio);
373 	if (!gpio->domain)
374 		return;
375 
376 	err = irq_alloc_domain_generic_chips(gpio->domain, ngpio, 2,
377 					     "gpio-dwapb", handle_level_irq,
378 					     IRQ_NOREQUEST, 0,
379 					     IRQ_GC_INIT_NESTED_LOCK);
380 	if (err) {
381 		dev_info(gpio->dev, "irq_alloc_domain_generic_chips failed\n");
382 		irq_domain_remove(gpio->domain);
383 		gpio->domain = NULL;
384 		return;
385 	}
386 
387 	irq_gc = irq_get_domain_generic_chip(gpio->domain, 0);
388 	if (!irq_gc) {
389 		irq_domain_remove(gpio->domain);
390 		gpio->domain = NULL;
391 		return;
392 	}
393 
394 	irq_gc->reg_base = gpio->regs;
395 	irq_gc->private = gpio;
396 
397 	for (i = 0; i < 2; i++) {
398 		ct = &irq_gc->chip_types[i];
399 		ct->chip.irq_ack = irq_gc_ack_set_bit;
400 		ct->chip.irq_mask = irq_gc_mask_set_bit;
401 		ct->chip.irq_unmask = irq_gc_mask_clr_bit;
402 		ct->chip.irq_set_type = dwapb_irq_set_type;
403 		ct->chip.irq_enable = dwapb_irq_enable;
404 		ct->chip.irq_disable = dwapb_irq_disable;
405 		ct->chip.irq_request_resources = dwapb_irq_reqres;
406 		ct->chip.irq_release_resources = dwapb_irq_relres;
407 #ifdef CONFIG_PM_SLEEP
408 		ct->chip.irq_set_wake = dwapb_irq_set_wake;
409 #endif
410 		ct->regs.ack = gpio_reg_convert(gpio, GPIO_PORTA_EOI);
411 		ct->regs.mask = gpio_reg_convert(gpio, GPIO_INTMASK);
412 		ct->type = IRQ_TYPE_LEVEL_MASK;
413 	}
414 
415 	irq_gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK;
416 	irq_gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH;
417 	irq_gc->chip_types[1].handler = handle_edge_irq;
418 
419 	if (!pp->irq_shared) {
420 		irq_set_chained_handler_and_data(pp->irq, dwapb_irq_handler,
421 						 gpio);
422 	} else {
423 		/*
424 		 * Request a shared IRQ since where MFD would have devices
425 		 * using the same irq pin
426 		 */
427 		err = devm_request_irq(gpio->dev, pp->irq,
428 				       dwapb_irq_handler_mfd,
429 				       IRQF_SHARED, "gpio-dwapb-mfd", gpio);
430 		if (err) {
431 			dev_err(gpio->dev, "error requesting IRQ\n");
432 			irq_domain_remove(gpio->domain);
433 			gpio->domain = NULL;
434 			return;
435 		}
436 	}
437 
438 	for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
439 		irq_create_mapping(gpio->domain, hwirq);
440 
441 	port->gc.to_irq = dwapb_gpio_to_irq;
442 }
443 
444 static void dwapb_irq_teardown(struct dwapb_gpio *gpio)
445 {
446 	struct dwapb_gpio_port *port = &gpio->ports[0];
447 	struct gpio_chip *gc = &port->gc;
448 	unsigned int ngpio = gc->ngpio;
449 	irq_hw_number_t hwirq;
450 
451 	if (!gpio->domain)
452 		return;
453 
454 	for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
455 		irq_dispose_mapping(irq_find_mapping(gpio->domain, hwirq));
456 
457 	irq_domain_remove(gpio->domain);
458 	gpio->domain = NULL;
459 }
460 
461 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
462 			       struct dwapb_port_property *pp,
463 			       unsigned int offs)
464 {
465 	struct dwapb_gpio_port *port;
466 	void __iomem *dat, *set, *dirout;
467 	int err;
468 
469 	port = &gpio->ports[offs];
470 	port->gpio = gpio;
471 	port->idx = pp->idx;
472 
473 #ifdef CONFIG_PM_SLEEP
474 	port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL);
475 	if (!port->ctx)
476 		return -ENOMEM;
477 #endif
478 
479 	dat = gpio->regs + GPIO_EXT_PORTA + (pp->idx * GPIO_EXT_PORT_SIZE);
480 	set = gpio->regs + GPIO_SWPORTA_DR + (pp->idx * GPIO_SWPORT_DR_SIZE);
481 	dirout = gpio->regs + GPIO_SWPORTA_DDR +
482 		(pp->idx * GPIO_SWPORT_DDR_SIZE);
483 
484 	err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
485 			 NULL, 0);
486 	if (err) {
487 		dev_err(gpio->dev, "failed to init gpio chip for port%d\n",
488 			port->idx);
489 		return err;
490 	}
491 
492 #ifdef CONFIG_OF_GPIO
493 	port->gc.of_node = to_of_node(pp->fwnode);
494 #endif
495 	port->gc.ngpio = pp->ngpio;
496 	port->gc.base = pp->gpio_base;
497 
498 	/* Only port A support debounce */
499 	if (pp->idx == 0)
500 		port->gc.set_config = dwapb_gpio_set_config;
501 
502 	if (pp->irq)
503 		dwapb_configure_irqs(gpio, port, pp);
504 
505 	err = gpiochip_add_data(&port->gc, port);
506 	if (err)
507 		dev_err(gpio->dev, "failed to register gpiochip for port%d\n",
508 			port->idx);
509 	else
510 		port->is_registered = true;
511 
512 	/* Add GPIO-signaled ACPI event support */
513 	if (pp->irq)
514 		acpi_gpiochip_request_interrupts(&port->gc);
515 
516 	return err;
517 }
518 
519 static void dwapb_gpio_unregister(struct dwapb_gpio *gpio)
520 {
521 	unsigned int m;
522 
523 	for (m = 0; m < gpio->nr_ports; ++m)
524 		if (gpio->ports[m].is_registered)
525 			gpiochip_remove(&gpio->ports[m].gc);
526 }
527 
528 static struct dwapb_platform_data *
529 dwapb_gpio_get_pdata(struct device *dev)
530 {
531 	struct fwnode_handle *fwnode;
532 	struct dwapb_platform_data *pdata;
533 	struct dwapb_port_property *pp;
534 	int nports;
535 	int i;
536 
537 	nports = device_get_child_node_count(dev);
538 	if (nports == 0)
539 		return ERR_PTR(-ENODEV);
540 
541 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
542 	if (!pdata)
543 		return ERR_PTR(-ENOMEM);
544 
545 	pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL);
546 	if (!pdata->properties)
547 		return ERR_PTR(-ENOMEM);
548 
549 	pdata->nports = nports;
550 
551 	i = 0;
552 	device_for_each_child_node(dev, fwnode)  {
553 		pp = &pdata->properties[i++];
554 		pp->fwnode = fwnode;
555 
556 		if (fwnode_property_read_u32(fwnode, "reg", &pp->idx) ||
557 		    pp->idx >= DWAPB_MAX_PORTS) {
558 			dev_err(dev,
559 				"missing/invalid port index for port%d\n", i);
560 			fwnode_handle_put(fwnode);
561 			return ERR_PTR(-EINVAL);
562 		}
563 
564 		if (fwnode_property_read_u32(fwnode, "snps,nr-gpios",
565 					 &pp->ngpio)) {
566 			dev_info(dev,
567 				 "failed to get number of gpios for port%d\n",
568 				 i);
569 			pp->ngpio = 32;
570 		}
571 
572 		/*
573 		 * Only port A can provide interrupts in all configurations of
574 		 * the IP.
575 		 */
576 		if (dev->of_node && pp->idx == 0 &&
577 			fwnode_property_read_bool(fwnode,
578 						  "interrupt-controller")) {
579 			pp->irq = irq_of_parse_and_map(to_of_node(fwnode), 0);
580 			if (!pp->irq)
581 				dev_warn(dev, "no irq for port%d\n", pp->idx);
582 		}
583 
584 		if (has_acpi_companion(dev) && pp->idx == 0)
585 			pp->irq = platform_get_irq(to_platform_device(dev), 0);
586 
587 		pp->irq_shared	= false;
588 		pp->gpio_base	= -1;
589 	}
590 
591 	return pdata;
592 }
593 
594 static const struct of_device_id dwapb_of_match[] = {
595 	{ .compatible = "snps,dw-apb-gpio", .data = (void *)0},
596 	{ .compatible = "apm,xgene-gpio-v2", .data = (void *)GPIO_REG_OFFSET_V2},
597 	{ /* Sentinel */ }
598 };
599 MODULE_DEVICE_TABLE(of, dwapb_of_match);
600 
601 static const struct acpi_device_id dwapb_acpi_match[] = {
602 	{"HISI0181", 0},
603 	{"APMC0D07", 0},
604 	{"APMC0D81", GPIO_REG_OFFSET_V2},
605 	{ }
606 };
607 MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
608 
609 static int dwapb_gpio_probe(struct platform_device *pdev)
610 {
611 	unsigned int i;
612 	struct resource *res;
613 	struct dwapb_gpio *gpio;
614 	int err;
615 	struct device *dev = &pdev->dev;
616 	struct dwapb_platform_data *pdata = dev_get_platdata(dev);
617 
618 	if (!pdata) {
619 		pdata = dwapb_gpio_get_pdata(dev);
620 		if (IS_ERR(pdata))
621 			return PTR_ERR(pdata);
622 	}
623 
624 	if (!pdata->nports)
625 		return -ENODEV;
626 
627 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
628 	if (!gpio)
629 		return -ENOMEM;
630 
631 	gpio->dev = &pdev->dev;
632 	gpio->nr_ports = pdata->nports;
633 
634 	gpio->rst = devm_reset_control_get_optional_shared(dev, NULL);
635 	if (IS_ERR(gpio->rst))
636 		return PTR_ERR(gpio->rst);
637 
638 	reset_control_deassert(gpio->rst);
639 
640 	gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports,
641 				   sizeof(*gpio->ports), GFP_KERNEL);
642 	if (!gpio->ports)
643 		return -ENOMEM;
644 
645 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
646 	gpio->regs = devm_ioremap_resource(&pdev->dev, res);
647 	if (IS_ERR(gpio->regs))
648 		return PTR_ERR(gpio->regs);
649 
650 	gpio->flags = 0;
651 	if (dev->of_node) {
652 		const struct of_device_id *of_devid;
653 
654 		of_devid = of_match_device(dwapb_of_match, dev);
655 		if (of_devid) {
656 			if (of_devid->data)
657 				gpio->flags = (uintptr_t)of_devid->data;
658 		}
659 	} else if (has_acpi_companion(dev)) {
660 		const struct acpi_device_id *acpi_id;
661 
662 		acpi_id = acpi_match_device(dwapb_acpi_match, dev);
663 		if (acpi_id) {
664 			if (acpi_id->driver_data)
665 				gpio->flags = acpi_id->driver_data;
666 		}
667 	}
668 
669 	for (i = 0; i < gpio->nr_ports; i++) {
670 		err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
671 		if (err)
672 			goto out_unregister;
673 	}
674 	platform_set_drvdata(pdev, gpio);
675 
676 	return 0;
677 
678 out_unregister:
679 	dwapb_gpio_unregister(gpio);
680 	dwapb_irq_teardown(gpio);
681 
682 	return err;
683 }
684 
685 static int dwapb_gpio_remove(struct platform_device *pdev)
686 {
687 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
688 
689 	dwapb_gpio_unregister(gpio);
690 	dwapb_irq_teardown(gpio);
691 	reset_control_assert(gpio->rst);
692 
693 	return 0;
694 }
695 
696 #ifdef CONFIG_PM_SLEEP
697 static int dwapb_gpio_suspend(struct device *dev)
698 {
699 	struct platform_device *pdev = to_platform_device(dev);
700 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
701 	struct gpio_chip *gc	= &gpio->ports[0].gc;
702 	unsigned long flags;
703 	int i;
704 
705 	spin_lock_irqsave(&gc->bgpio_lock, flags);
706 	for (i = 0; i < gpio->nr_ports; i++) {
707 		unsigned int offset;
708 		unsigned int idx = gpio->ports[i].idx;
709 		struct dwapb_context *ctx = gpio->ports[i].ctx;
710 
711 		BUG_ON(!ctx);
712 
713 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_SIZE;
714 		ctx->dir = dwapb_read(gpio, offset);
715 
716 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_SIZE;
717 		ctx->data = dwapb_read(gpio, offset);
718 
719 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_SIZE;
720 		ctx->ext = dwapb_read(gpio, offset);
721 
722 		/* Only port A can provide interrupts */
723 		if (idx == 0) {
724 			ctx->int_mask	= dwapb_read(gpio, GPIO_INTMASK);
725 			ctx->int_en	= dwapb_read(gpio, GPIO_INTEN);
726 			ctx->int_pol	= dwapb_read(gpio, GPIO_INT_POLARITY);
727 			ctx->int_type	= dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
728 			ctx->int_deb	= dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
729 
730 			/* Mask out interrupts */
731 			dwapb_write(gpio, GPIO_INTMASK,
732 				    0xffffffff & ~ctx->wake_en);
733 		}
734 	}
735 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
736 
737 	return 0;
738 }
739 
740 static int dwapb_gpio_resume(struct device *dev)
741 {
742 	struct platform_device *pdev = to_platform_device(dev);
743 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
744 	struct gpio_chip *gc	= &gpio->ports[0].gc;
745 	unsigned long flags;
746 	int i;
747 
748 	spin_lock_irqsave(&gc->bgpio_lock, flags);
749 	for (i = 0; i < gpio->nr_ports; i++) {
750 		unsigned int offset;
751 		unsigned int idx = gpio->ports[i].idx;
752 		struct dwapb_context *ctx = gpio->ports[i].ctx;
753 
754 		BUG_ON(!ctx);
755 
756 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_SIZE;
757 		dwapb_write(gpio, offset, ctx->data);
758 
759 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_SIZE;
760 		dwapb_write(gpio, offset, ctx->dir);
761 
762 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_SIZE;
763 		dwapb_write(gpio, offset, ctx->ext);
764 
765 		/* Only port A can provide interrupts */
766 		if (idx == 0) {
767 			dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
768 			dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
769 			dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
770 			dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
771 			dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask);
772 
773 			/* Clear out spurious interrupts */
774 			dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
775 		}
776 	}
777 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
778 
779 	return 0;
780 }
781 #endif
782 
783 static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
784 			 dwapb_gpio_resume);
785 
786 static struct platform_driver dwapb_gpio_driver = {
787 	.driver		= {
788 		.name	= "gpio-dwapb",
789 		.pm	= &dwapb_gpio_pm_ops,
790 		.of_match_table = of_match_ptr(dwapb_of_match),
791 		.acpi_match_table = ACPI_PTR(dwapb_acpi_match),
792 	},
793 	.probe		= dwapb_gpio_probe,
794 	.remove		= dwapb_gpio_remove,
795 };
796 
797 module_platform_driver(dwapb_gpio_driver);
798 
799 MODULE_LICENSE("GPL");
800 MODULE_AUTHOR("Jamie Iles");
801 MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
802