xref: /linux/drivers/gpio/gpio-dwapb.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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/platform_device.h>
19 #include <linux/property.h>
20 #include <linux/reset.h>
21 #include <linux/slab.h>
22 #include <linux/spinlock.h>
23 
24 #include "gpiolib-acpi.h"
25 
26 #define GPIO_SWPORTA_DR		0x00
27 #define GPIO_SWPORTA_DDR	0x04
28 #define GPIO_SWPORTB_DR		0x0c
29 #define GPIO_SWPORTB_DDR	0x10
30 #define GPIO_SWPORTC_DR		0x18
31 #define GPIO_SWPORTC_DDR	0x1c
32 #define GPIO_SWPORTD_DR		0x24
33 #define GPIO_SWPORTD_DDR	0x28
34 #define GPIO_INTEN		0x30
35 #define GPIO_INTMASK		0x34
36 #define GPIO_INTTYPE_LEVEL	0x38
37 #define GPIO_INT_POLARITY	0x3c
38 #define GPIO_INTSTATUS		0x40
39 #define GPIO_PORTA_DEBOUNCE	0x48
40 #define GPIO_PORTA_EOI		0x4c
41 #define GPIO_EXT_PORTA		0x50
42 #define GPIO_EXT_PORTB		0x54
43 #define GPIO_EXT_PORTC		0x58
44 #define GPIO_EXT_PORTD		0x5c
45 
46 #define DWAPB_DRIVER_NAME	"gpio-dwapb"
47 #define DWAPB_MAX_PORTS		4
48 #define DWAPB_MAX_GPIOS		32
49 
50 #define GPIO_EXT_PORT_STRIDE	0x04 /* register stride 32 bits */
51 #define GPIO_SWPORT_DR_STRIDE	0x0c /* register stride 3*32 bits */
52 #define GPIO_SWPORT_DDR_STRIDE	0x0c /* register stride 3*32 bits */
53 
54 #define GPIO_REG_OFFSET_V1	0
55 #define GPIO_REG_OFFSET_V2	1
56 #define GPIO_REG_OFFSET_MASK	BIT(0)
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 struct dwapb_port_property {
69 	struct fwnode_handle *fwnode;
70 	unsigned int idx;
71 	unsigned int ngpio;
72 	unsigned int gpio_base;
73 	int irq[DWAPB_MAX_GPIOS];
74 };
75 
76 struct dwapb_platform_data {
77 	struct dwapb_port_property *properties;
78 	unsigned int nports;
79 };
80 
81 #ifdef CONFIG_PM_SLEEP
82 /* Store GPIO context across system-wide suspend/resume transitions */
83 struct dwapb_context {
84 	u32 data;
85 	u32 dir;
86 	u32 ext;
87 	u32 int_en;
88 	u32 int_mask;
89 	u32 int_type;
90 	u32 int_pol;
91 	u32 int_deb;
92 	u32 wake_en;
93 };
94 #endif
95 
96 struct dwapb_gpio_port_irqchip {
97 	unsigned int		nr_irqs;
98 	unsigned int		irq[DWAPB_MAX_GPIOS];
99 };
100 
101 struct dwapb_gpio_port {
102 	struct gpio_chip	gc;
103 	struct dwapb_gpio_port_irqchip *pirq;
104 	struct dwapb_gpio	*gpio;
105 #ifdef CONFIG_PM_SLEEP
106 	struct dwapb_context	*ctx;
107 #endif
108 	unsigned int		idx;
109 };
110 #define to_dwapb_gpio(_gc) \
111 	(container_of(_gc, struct dwapb_gpio_port, gc)->gpio)
112 
113 struct dwapb_gpio {
114 	struct	device		*dev;
115 	void __iomem		*regs;
116 	struct dwapb_gpio_port	*ports;
117 	unsigned int		nr_ports;
118 	unsigned int		flags;
119 	struct reset_control	*rst;
120 	struct clk_bulk_data	clks[DWAPB_NR_CLOCKS];
121 };
122 
123 static inline u32 gpio_reg_v2_convert(unsigned int offset)
124 {
125 	switch (offset) {
126 	case GPIO_INTMASK:
127 		return GPIO_INTMASK_V2;
128 	case GPIO_INTTYPE_LEVEL:
129 		return GPIO_INTTYPE_LEVEL_V2;
130 	case GPIO_INT_POLARITY:
131 		return GPIO_INT_POLARITY_V2;
132 	case GPIO_INTSTATUS:
133 		return GPIO_INTSTATUS_V2;
134 	case GPIO_PORTA_EOI:
135 		return GPIO_PORTA_EOI_V2;
136 	}
137 
138 	return offset;
139 }
140 
141 static inline u32 gpio_reg_convert(struct dwapb_gpio *gpio, unsigned int offset)
142 {
143 	if ((gpio->flags & GPIO_REG_OFFSET_MASK) == GPIO_REG_OFFSET_V2)
144 		return gpio_reg_v2_convert(offset);
145 
146 	return offset;
147 }
148 
149 static inline u32 dwapb_read(struct dwapb_gpio *gpio, unsigned int offset)
150 {
151 	struct gpio_chip *gc	= &gpio->ports[0].gc;
152 	void __iomem *reg_base	= gpio->regs;
153 
154 	return gc->read_reg(reg_base + gpio_reg_convert(gpio, offset));
155 }
156 
157 static inline void dwapb_write(struct dwapb_gpio *gpio, unsigned int offset,
158 			       u32 val)
159 {
160 	struct gpio_chip *gc	= &gpio->ports[0].gc;
161 	void __iomem *reg_base	= gpio->regs;
162 
163 	gc->write_reg(reg_base + gpio_reg_convert(gpio, offset), val);
164 }
165 
166 static struct dwapb_gpio_port *dwapb_offs_to_port(struct dwapb_gpio *gpio, unsigned int offs)
167 {
168 	struct dwapb_gpio_port *port;
169 	int i;
170 
171 	for (i = 0; i < gpio->nr_ports; i++) {
172 		port = &gpio->ports[i];
173 		if (port->idx == offs / DWAPB_MAX_GPIOS)
174 			return port;
175 	}
176 
177 	return NULL;
178 }
179 
180 static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
181 {
182 	struct dwapb_gpio_port *port = dwapb_offs_to_port(gpio, offs);
183 	struct gpio_chip *gc;
184 	u32 pol;
185 	int val;
186 
187 	if (!port)
188 		return;
189 	gc = &port->gc;
190 
191 	pol = dwapb_read(gpio, GPIO_INT_POLARITY);
192 	/* Just read the current value right out of the data register */
193 	val = gc->get(gc, offs % DWAPB_MAX_GPIOS);
194 	if (val)
195 		pol &= ~BIT(offs);
196 	else
197 		pol |= BIT(offs);
198 
199 	dwapb_write(gpio, GPIO_INT_POLARITY, pol);
200 }
201 
202 static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
203 {
204 	struct gpio_chip *gc = &gpio->ports[0].gc;
205 	unsigned long irq_status;
206 	irq_hw_number_t hwirq;
207 
208 	irq_status = dwapb_read(gpio, GPIO_INTSTATUS);
209 	for_each_set_bit(hwirq, &irq_status, DWAPB_MAX_GPIOS) {
210 		int gpio_irq = irq_find_mapping(gc->irq.domain, hwirq);
211 		u32 irq_type = irq_get_trigger_type(gpio_irq);
212 
213 		generic_handle_irq(gpio_irq);
214 
215 		if ((irq_type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
216 			dwapb_toggle_trigger(gpio, hwirq);
217 	}
218 
219 	return irq_status;
220 }
221 
222 static void dwapb_irq_handler(struct irq_desc *desc)
223 {
224 	struct dwapb_gpio *gpio = irq_desc_get_handler_data(desc);
225 	struct irq_chip *chip = irq_desc_get_chip(desc);
226 
227 	chained_irq_enter(chip, desc);
228 	dwapb_do_irq(gpio);
229 	chained_irq_exit(chip, desc);
230 }
231 
232 static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id)
233 {
234 	return IRQ_RETVAL(dwapb_do_irq(dev_id));
235 }
236 
237 static void dwapb_irq_ack(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 	u32 val = BIT(irqd_to_hwirq(d));
242 	unsigned long flags;
243 
244 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
245 	dwapb_write(gpio, GPIO_PORTA_EOI, val);
246 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
247 }
248 
249 static void dwapb_irq_mask(struct irq_data *d)
250 {
251 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
252 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
253 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
254 	unsigned long flags;
255 	u32 val;
256 
257 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
258 	val = dwapb_read(gpio, GPIO_INTMASK) | BIT(hwirq);
259 	dwapb_write(gpio, GPIO_INTMASK, val);
260 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
261 
262 	gpiochip_disable_irq(gc, hwirq);
263 }
264 
265 static void dwapb_irq_unmask(struct irq_data *d)
266 {
267 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
268 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
269 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
270 	unsigned long flags;
271 	u32 val;
272 
273 	gpiochip_enable_irq(gc, hwirq);
274 
275 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
276 	val = dwapb_read(gpio, GPIO_INTMASK) & ~BIT(hwirq);
277 	dwapb_write(gpio, GPIO_INTMASK, val);
278 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
279 }
280 
281 static void dwapb_irq_enable(struct irq_data *d)
282 {
283 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
284 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
285 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
286 	unsigned long flags;
287 	u32 val;
288 
289 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
290 	val = dwapb_read(gpio, GPIO_INTEN) | BIT(hwirq);
291 	dwapb_write(gpio, GPIO_INTEN, val);
292 	val = dwapb_read(gpio, GPIO_INTMASK) & ~BIT(hwirq);
293 	dwapb_write(gpio, GPIO_INTMASK, val);
294 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
295 }
296 
297 static void dwapb_irq_disable(struct irq_data *d)
298 {
299 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
300 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
301 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
302 	unsigned long flags;
303 	u32 val;
304 
305 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
306 	val = dwapb_read(gpio, GPIO_INTMASK) | BIT(hwirq);
307 	dwapb_write(gpio, GPIO_INTMASK, val);
308 	val = dwapb_read(gpio, GPIO_INTEN) & ~BIT(hwirq);
309 	dwapb_write(gpio, GPIO_INTEN, val);
310 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
311 }
312 
313 static int dwapb_irq_set_type(struct irq_data *d, u32 type)
314 {
315 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
316 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
317 	irq_hw_number_t bit = irqd_to_hwirq(d);
318 	unsigned long level, polarity, flags;
319 
320 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
321 	level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
322 	polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
323 
324 	switch (type) {
325 	case IRQ_TYPE_EDGE_BOTH:
326 		level |= BIT(bit);
327 		dwapb_toggle_trigger(gpio, bit);
328 		break;
329 	case IRQ_TYPE_EDGE_RISING:
330 		level |= BIT(bit);
331 		polarity |= BIT(bit);
332 		break;
333 	case IRQ_TYPE_EDGE_FALLING:
334 		level |= BIT(bit);
335 		polarity &= ~BIT(bit);
336 		break;
337 	case IRQ_TYPE_LEVEL_HIGH:
338 		level &= ~BIT(bit);
339 		polarity |= BIT(bit);
340 		break;
341 	case IRQ_TYPE_LEVEL_LOW:
342 		level &= ~BIT(bit);
343 		polarity &= ~BIT(bit);
344 		break;
345 	}
346 
347 	if (type & IRQ_TYPE_LEVEL_MASK)
348 		irq_set_handler_locked(d, handle_level_irq);
349 	else if (type & IRQ_TYPE_EDGE_BOTH)
350 		irq_set_handler_locked(d, handle_edge_irq);
351 
352 	dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level);
353 	if (type != IRQ_TYPE_EDGE_BOTH)
354 		dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
355 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
356 
357 	return 0;
358 }
359 
360 #ifdef CONFIG_PM_SLEEP
361 static int dwapb_irq_set_wake(struct irq_data *d, unsigned int enable)
362 {
363 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
364 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
365 	struct dwapb_context *ctx = gpio->ports[0].ctx;
366 	irq_hw_number_t bit = irqd_to_hwirq(d);
367 
368 	if (enable)
369 		ctx->wake_en |= BIT(bit);
370 	else
371 		ctx->wake_en &= ~BIT(bit);
372 
373 	return 0;
374 }
375 #else
376 #define dwapb_irq_set_wake	NULL
377 #endif
378 
379 static const struct irq_chip dwapb_irq_chip = {
380 	.name		= DWAPB_DRIVER_NAME,
381 	.irq_ack	= dwapb_irq_ack,
382 	.irq_mask	= dwapb_irq_mask,
383 	.irq_unmask	= dwapb_irq_unmask,
384 	.irq_set_type	= dwapb_irq_set_type,
385 	.irq_enable	= dwapb_irq_enable,
386 	.irq_disable	= dwapb_irq_disable,
387 	.irq_set_wake	= dwapb_irq_set_wake,
388 	.flags		= IRQCHIP_IMMUTABLE,
389 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
390 };
391 
392 static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
393 				   unsigned offset, unsigned debounce)
394 {
395 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
396 	struct dwapb_gpio *gpio = port->gpio;
397 	unsigned long flags, val_deb;
398 	unsigned long mask = BIT(offset);
399 
400 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
401 
402 	val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
403 	if (debounce)
404 		val_deb |= mask;
405 	else
406 		val_deb &= ~mask;
407 	dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb);
408 
409 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
410 
411 	return 0;
412 }
413 
414 static int dwapb_gpio_set_config(struct gpio_chip *gc, unsigned offset,
415 				 unsigned long config)
416 {
417 	u32 debounce;
418 
419 	if (pinconf_to_config_param(config) == PIN_CONFIG_INPUT_DEBOUNCE) {
420 		debounce = pinconf_to_config_argument(config);
421 		return dwapb_gpio_set_debounce(gc, offset, debounce);
422 	}
423 
424 	return gpiochip_generic_config(gc, offset, config);
425 }
426 
427 static int dwapb_convert_irqs(struct dwapb_gpio_port_irqchip *pirq,
428 			      struct dwapb_port_property *pp)
429 {
430 	int i;
431 
432 	/* Group all available IRQs into an array of parental IRQs. */
433 	for (i = 0; i < pp->ngpio; ++i) {
434 		if (!pp->irq[i])
435 			continue;
436 
437 		pirq->irq[pirq->nr_irqs++] = pp->irq[i];
438 	}
439 
440 	return pirq->nr_irqs ? 0 : -ENOENT;
441 }
442 
443 static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
444 				 struct dwapb_gpio_port *port,
445 				 struct dwapb_port_property *pp)
446 {
447 	struct dwapb_gpio_port_irqchip *pirq;
448 	struct gpio_chip *gc = &port->gc;
449 	struct gpio_irq_chip *girq;
450 	int err;
451 
452 	pirq = devm_kzalloc(gpio->dev, sizeof(*pirq), GFP_KERNEL);
453 	if (!pirq)
454 		return;
455 
456 	if (dwapb_convert_irqs(pirq, pp)) {
457 		dev_warn(gpio->dev, "no IRQ for port%d\n", pp->idx);
458 		goto err_kfree_pirq;
459 	}
460 
461 	girq = &gc->irq;
462 	girq->handler = handle_bad_irq;
463 	girq->default_type = IRQ_TYPE_NONE;
464 
465 	port->pirq = pirq;
466 
467 	/*
468 	 * Intel ACPI-based platforms mostly have the DesignWare APB GPIO
469 	 * IRQ lane shared between several devices. In that case the parental
470 	 * IRQ has to be handled in the shared way so to be properly delivered
471 	 * to all the connected devices.
472 	 */
473 	if (has_acpi_companion(gpio->dev)) {
474 		girq->num_parents = 0;
475 		girq->parents = NULL;
476 		girq->parent_handler = NULL;
477 
478 		err = devm_request_irq(gpio->dev, pp->irq[0],
479 				       dwapb_irq_handler_mfd,
480 				       IRQF_SHARED, DWAPB_DRIVER_NAME, gpio);
481 		if (err) {
482 			dev_err(gpio->dev, "error requesting IRQ\n");
483 			goto err_kfree_pirq;
484 		}
485 	} else {
486 		girq->num_parents = pirq->nr_irqs;
487 		girq->parents = pirq->irq;
488 		girq->parent_handler_data = gpio;
489 		girq->parent_handler = dwapb_irq_handler;
490 	}
491 
492 	gpio_irq_chip_set_chip(girq, &dwapb_irq_chip);
493 
494 	return;
495 
496 err_kfree_pirq:
497 	devm_kfree(gpio->dev, pirq);
498 }
499 
500 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
501 			       struct dwapb_port_property *pp,
502 			       unsigned int offs)
503 {
504 	struct dwapb_gpio_port *port;
505 	void __iomem *dat, *set, *dirout;
506 	int err;
507 
508 	port = &gpio->ports[offs];
509 	port->gpio = gpio;
510 	port->idx = pp->idx;
511 
512 #ifdef CONFIG_PM_SLEEP
513 	port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL);
514 	if (!port->ctx)
515 		return -ENOMEM;
516 #endif
517 
518 	dat = gpio->regs + GPIO_EXT_PORTA + pp->idx * GPIO_EXT_PORT_STRIDE;
519 	set = gpio->regs + GPIO_SWPORTA_DR + pp->idx * GPIO_SWPORT_DR_STRIDE;
520 	dirout = gpio->regs + GPIO_SWPORTA_DDR + pp->idx * GPIO_SWPORT_DDR_STRIDE;
521 
522 	/* This registers 32 GPIO lines per port */
523 	err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
524 			 NULL, 0);
525 	if (err) {
526 		dev_err(gpio->dev, "failed to init gpio chip for port%d\n",
527 			port->idx);
528 		return err;
529 	}
530 
531 	port->gc.fwnode = pp->fwnode;
532 	port->gc.ngpio = pp->ngpio;
533 	port->gc.base = pp->gpio_base;
534 	port->gc.request = gpiochip_generic_request;
535 	port->gc.free = gpiochip_generic_free;
536 
537 	/* Only port A support debounce */
538 	if (pp->idx == 0)
539 		port->gc.set_config = dwapb_gpio_set_config;
540 	else
541 		port->gc.set_config = gpiochip_generic_config;
542 
543 	/* Only port A can provide interrupts in all configurations of the IP */
544 	if (pp->idx == 0)
545 		dwapb_configure_irqs(gpio, port, pp);
546 
547 	err = devm_gpiochip_add_data(gpio->dev, &port->gc, port);
548 	if (err) {
549 		dev_err(gpio->dev, "failed to register gpiochip for port%d\n",
550 			port->idx);
551 		return err;
552 	}
553 
554 	return 0;
555 }
556 
557 static void dwapb_get_irq(struct device *dev, struct fwnode_handle *fwnode,
558 			  struct dwapb_port_property *pp)
559 {
560 	int irq, j;
561 
562 	for (j = 0; j < pp->ngpio; j++) {
563 		if (has_acpi_companion(dev))
564 			irq = platform_get_irq_optional(to_platform_device(dev), j);
565 		else
566 			irq = fwnode_irq_get(fwnode, j);
567 		if (irq > 0)
568 			pp->irq[j] = irq;
569 	}
570 }
571 
572 static struct dwapb_platform_data *dwapb_gpio_get_pdata(struct device *dev)
573 {
574 	struct fwnode_handle *fwnode;
575 	struct dwapb_platform_data *pdata;
576 	struct dwapb_port_property *pp;
577 	int nports;
578 	int i;
579 
580 	nports = device_get_child_node_count(dev);
581 	if (nports == 0)
582 		return ERR_PTR(-ENODEV);
583 
584 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
585 	if (!pdata)
586 		return ERR_PTR(-ENOMEM);
587 
588 	pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL);
589 	if (!pdata->properties)
590 		return ERR_PTR(-ENOMEM);
591 
592 	pdata->nports = nports;
593 
594 	i = 0;
595 	device_for_each_child_node(dev, fwnode)  {
596 		pp = &pdata->properties[i++];
597 		pp->fwnode = fwnode;
598 
599 		if (fwnode_property_read_u32(fwnode, "reg", &pp->idx) ||
600 		    pp->idx >= DWAPB_MAX_PORTS) {
601 			dev_err(dev,
602 				"missing/invalid port index for port%d\n", i);
603 			fwnode_handle_put(fwnode);
604 			return ERR_PTR(-EINVAL);
605 		}
606 
607 		if (fwnode_property_read_u32(fwnode, "ngpios", &pp->ngpio) &&
608 		    fwnode_property_read_u32(fwnode, "snps,nr-gpios", &pp->ngpio)) {
609 			dev_info(dev,
610 				 "failed to get number of gpios for port%d\n",
611 				 i);
612 			pp->ngpio = DWAPB_MAX_GPIOS;
613 		}
614 
615 		pp->gpio_base	= -1;
616 
617 		/* For internal use only, new platforms mustn't exercise this */
618 		if (is_software_node(fwnode))
619 			fwnode_property_read_u32(fwnode, "gpio-base", &pp->gpio_base);
620 
621 		/*
622 		 * Only port A can provide interrupts in all configurations of
623 		 * the IP.
624 		 */
625 		if (pp->idx == 0)
626 			dwapb_get_irq(dev, fwnode, pp);
627 	}
628 
629 	return pdata;
630 }
631 
632 static void dwapb_assert_reset(void *data)
633 {
634 	struct dwapb_gpio *gpio = data;
635 
636 	reset_control_assert(gpio->rst);
637 }
638 
639 static int dwapb_get_reset(struct dwapb_gpio *gpio)
640 {
641 	int err;
642 
643 	gpio->rst = devm_reset_control_get_optional_shared(gpio->dev, NULL);
644 	if (IS_ERR(gpio->rst))
645 		return dev_err_probe(gpio->dev, PTR_ERR(gpio->rst),
646 				     "Cannot get reset descriptor\n");
647 
648 	err = reset_control_deassert(gpio->rst);
649 	if (err) {
650 		dev_err(gpio->dev, "Cannot deassert reset lane\n");
651 		return err;
652 	}
653 
654 	return devm_add_action_or_reset(gpio->dev, dwapb_assert_reset, gpio);
655 }
656 
657 static void dwapb_disable_clks(void *data)
658 {
659 	struct dwapb_gpio *gpio = data;
660 
661 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
662 }
663 
664 static int dwapb_get_clks(struct dwapb_gpio *gpio)
665 {
666 	int err;
667 
668 	/* Optional bus and debounce clocks */
669 	gpio->clks[0].id = "bus";
670 	gpio->clks[1].id = "db";
671 	err = devm_clk_bulk_get_optional(gpio->dev, DWAPB_NR_CLOCKS,
672 					 gpio->clks);
673 	if (err)
674 		return dev_err_probe(gpio->dev, err,
675 				     "Cannot get APB/Debounce clocks\n");
676 
677 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
678 	if (err) {
679 		dev_err(gpio->dev, "Cannot enable APB/Debounce clocks\n");
680 		return err;
681 	}
682 
683 	return devm_add_action_or_reset(gpio->dev, dwapb_disable_clks, gpio);
684 }
685 
686 static const struct of_device_id dwapb_of_match[] = {
687 	{ .compatible = "snps,dw-apb-gpio", .data = (void *)GPIO_REG_OFFSET_V1},
688 	{ .compatible = "apm,xgene-gpio-v2", .data = (void *)GPIO_REG_OFFSET_V2},
689 	{ /* Sentinel */ }
690 };
691 MODULE_DEVICE_TABLE(of, dwapb_of_match);
692 
693 static const struct acpi_device_id dwapb_acpi_match[] = {
694 	{"HISI0181", GPIO_REG_OFFSET_V1},
695 	{"APMC0D07", GPIO_REG_OFFSET_V1},
696 	{"APMC0D81", GPIO_REG_OFFSET_V2},
697 	{ }
698 };
699 MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
700 
701 static int dwapb_gpio_probe(struct platform_device *pdev)
702 {
703 	unsigned int i;
704 	struct dwapb_gpio *gpio;
705 	int err;
706 	struct dwapb_platform_data *pdata;
707 	struct device *dev = &pdev->dev;
708 
709 	pdata = dwapb_gpio_get_pdata(dev);
710 	if (IS_ERR(pdata))
711 		return PTR_ERR(pdata);
712 
713 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
714 	if (!gpio)
715 		return -ENOMEM;
716 
717 	gpio->dev = &pdev->dev;
718 	gpio->nr_ports = pdata->nports;
719 
720 	err = dwapb_get_reset(gpio);
721 	if (err)
722 		return err;
723 
724 	gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports,
725 				   sizeof(*gpio->ports), GFP_KERNEL);
726 	if (!gpio->ports)
727 		return -ENOMEM;
728 
729 	gpio->regs = devm_platform_ioremap_resource(pdev, 0);
730 	if (IS_ERR(gpio->regs))
731 		return PTR_ERR(gpio->regs);
732 
733 	err = dwapb_get_clks(gpio);
734 	if (err)
735 		return err;
736 
737 	gpio->flags = (uintptr_t)device_get_match_data(dev);
738 
739 	for (i = 0; i < gpio->nr_ports; i++) {
740 		err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
741 		if (err)
742 			return err;
743 	}
744 
745 	platform_set_drvdata(pdev, gpio);
746 
747 	return 0;
748 }
749 
750 #ifdef CONFIG_PM_SLEEP
751 static int dwapb_gpio_suspend(struct device *dev)
752 {
753 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
754 	struct gpio_chip *gc	= &gpio->ports[0].gc;
755 	unsigned long flags;
756 	int i;
757 
758 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
759 	for (i = 0; i < gpio->nr_ports; i++) {
760 		unsigned int offset;
761 		unsigned int idx = gpio->ports[i].idx;
762 		struct dwapb_context *ctx = gpio->ports[i].ctx;
763 
764 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
765 		ctx->dir = dwapb_read(gpio, offset);
766 
767 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
768 		ctx->data = dwapb_read(gpio, offset);
769 
770 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
771 		ctx->ext = dwapb_read(gpio, offset);
772 
773 		/* Only port A can provide interrupts */
774 		if (idx == 0) {
775 			ctx->int_mask	= dwapb_read(gpio, GPIO_INTMASK);
776 			ctx->int_en	= dwapb_read(gpio, GPIO_INTEN);
777 			ctx->int_pol	= dwapb_read(gpio, GPIO_INT_POLARITY);
778 			ctx->int_type	= dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
779 			ctx->int_deb	= dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
780 
781 			/* Mask out interrupts */
782 			dwapb_write(gpio, GPIO_INTMASK, ~ctx->wake_en);
783 		}
784 	}
785 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
786 
787 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
788 
789 	return 0;
790 }
791 
792 static int dwapb_gpio_resume(struct device *dev)
793 {
794 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
795 	struct gpio_chip *gc	= &gpio->ports[0].gc;
796 	unsigned long flags;
797 	int i, err;
798 
799 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
800 	if (err) {
801 		dev_err(gpio->dev, "Cannot reenable APB/Debounce clocks\n");
802 		return err;
803 	}
804 
805 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
806 	for (i = 0; i < gpio->nr_ports; i++) {
807 		unsigned int offset;
808 		unsigned int idx = gpio->ports[i].idx;
809 		struct dwapb_context *ctx = gpio->ports[i].ctx;
810 
811 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
812 		dwapb_write(gpio, offset, ctx->data);
813 
814 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
815 		dwapb_write(gpio, offset, ctx->dir);
816 
817 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
818 		dwapb_write(gpio, offset, ctx->ext);
819 
820 		/* Only port A can provide interrupts */
821 		if (idx == 0) {
822 			dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
823 			dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
824 			dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
825 			dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
826 			dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask);
827 
828 			/* Clear out spurious interrupts */
829 			dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
830 		}
831 	}
832 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
833 
834 	return 0;
835 }
836 #endif
837 
838 static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
839 			 dwapb_gpio_resume);
840 
841 static struct platform_driver dwapb_gpio_driver = {
842 	.driver		= {
843 		.name	= DWAPB_DRIVER_NAME,
844 		.pm	= &dwapb_gpio_pm_ops,
845 		.of_match_table = dwapb_of_match,
846 		.acpi_match_table = dwapb_acpi_match,
847 	},
848 	.probe		= dwapb_gpio_probe,
849 };
850 
851 module_platform_driver(dwapb_gpio_driver);
852 
853 MODULE_LICENSE("GPL");
854 MODULE_AUTHOR("Jamie Iles");
855 MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
856 MODULE_ALIAS("platform:" DWAPB_DRIVER_NAME);
857