xref: /linux/drivers/gpio/gpio-dwapb.c (revision 0678df8271820bcf8fb4f877129f05d68a237de4)
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 	unsigned long flags;
286 	u32 val;
287 
288 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
289 	val = dwapb_read(gpio, GPIO_INTEN);
290 	val |= BIT(irqd_to_hwirq(d));
291 	dwapb_write(gpio, GPIO_INTEN, val);
292 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
293 }
294 
295 static void dwapb_irq_disable(struct irq_data *d)
296 {
297 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
298 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
299 	unsigned long flags;
300 	u32 val;
301 
302 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
303 	val = dwapb_read(gpio, GPIO_INTEN);
304 	val &= ~BIT(irqd_to_hwirq(d));
305 	dwapb_write(gpio, GPIO_INTEN, val);
306 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
307 }
308 
309 static int dwapb_irq_set_type(struct irq_data *d, u32 type)
310 {
311 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
312 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
313 	irq_hw_number_t bit = irqd_to_hwirq(d);
314 	unsigned long level, polarity, flags;
315 
316 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
317 	level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
318 	polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
319 
320 	switch (type) {
321 	case IRQ_TYPE_EDGE_BOTH:
322 		level |= BIT(bit);
323 		dwapb_toggle_trigger(gpio, bit);
324 		break;
325 	case IRQ_TYPE_EDGE_RISING:
326 		level |= BIT(bit);
327 		polarity |= BIT(bit);
328 		break;
329 	case IRQ_TYPE_EDGE_FALLING:
330 		level |= BIT(bit);
331 		polarity &= ~BIT(bit);
332 		break;
333 	case IRQ_TYPE_LEVEL_HIGH:
334 		level &= ~BIT(bit);
335 		polarity |= BIT(bit);
336 		break;
337 	case IRQ_TYPE_LEVEL_LOW:
338 		level &= ~BIT(bit);
339 		polarity &= ~BIT(bit);
340 		break;
341 	}
342 
343 	if (type & IRQ_TYPE_LEVEL_MASK)
344 		irq_set_handler_locked(d, handle_level_irq);
345 	else if (type & IRQ_TYPE_EDGE_BOTH)
346 		irq_set_handler_locked(d, handle_edge_irq);
347 
348 	dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level);
349 	if (type != IRQ_TYPE_EDGE_BOTH)
350 		dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
351 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
352 
353 	return 0;
354 }
355 
356 #ifdef CONFIG_PM_SLEEP
357 static int dwapb_irq_set_wake(struct irq_data *d, unsigned int enable)
358 {
359 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
360 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
361 	struct dwapb_context *ctx = gpio->ports[0].ctx;
362 	irq_hw_number_t bit = irqd_to_hwirq(d);
363 
364 	if (enable)
365 		ctx->wake_en |= BIT(bit);
366 	else
367 		ctx->wake_en &= ~BIT(bit);
368 
369 	return 0;
370 }
371 #else
372 #define dwapb_irq_set_wake	NULL
373 #endif
374 
375 static const struct irq_chip dwapb_irq_chip = {
376 	.name		= DWAPB_DRIVER_NAME,
377 	.irq_ack	= dwapb_irq_ack,
378 	.irq_mask	= dwapb_irq_mask,
379 	.irq_unmask	= dwapb_irq_unmask,
380 	.irq_set_type	= dwapb_irq_set_type,
381 	.irq_enable	= dwapb_irq_enable,
382 	.irq_disable	= dwapb_irq_disable,
383 	.irq_set_wake	= dwapb_irq_set_wake,
384 	.flags		= IRQCHIP_IMMUTABLE,
385 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
386 };
387 
388 static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
389 				   unsigned offset, unsigned debounce)
390 {
391 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
392 	struct dwapb_gpio *gpio = port->gpio;
393 	unsigned long flags, val_deb;
394 	unsigned long mask = BIT(offset);
395 
396 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
397 
398 	val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
399 	if (debounce)
400 		val_deb |= mask;
401 	else
402 		val_deb &= ~mask;
403 	dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb);
404 
405 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
406 
407 	return 0;
408 }
409 
410 static int dwapb_gpio_set_config(struct gpio_chip *gc, unsigned offset,
411 				 unsigned long config)
412 {
413 	u32 debounce;
414 
415 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
416 		return -ENOTSUPP;
417 
418 	debounce = pinconf_to_config_argument(config);
419 	return dwapb_gpio_set_debounce(gc, offset, debounce);
420 }
421 
422 static int dwapb_convert_irqs(struct dwapb_gpio_port_irqchip *pirq,
423 			      struct dwapb_port_property *pp)
424 {
425 	int i;
426 
427 	/* Group all available IRQs into an array of parental IRQs. */
428 	for (i = 0; i < pp->ngpio; ++i) {
429 		if (!pp->irq[i])
430 			continue;
431 
432 		pirq->irq[pirq->nr_irqs++] = pp->irq[i];
433 	}
434 
435 	return pirq->nr_irqs ? 0 : -ENOENT;
436 }
437 
438 static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
439 				 struct dwapb_gpio_port *port,
440 				 struct dwapb_port_property *pp)
441 {
442 	struct dwapb_gpio_port_irqchip *pirq;
443 	struct gpio_chip *gc = &port->gc;
444 	struct gpio_irq_chip *girq;
445 	int err;
446 
447 	pirq = devm_kzalloc(gpio->dev, sizeof(*pirq), GFP_KERNEL);
448 	if (!pirq)
449 		return;
450 
451 	if (dwapb_convert_irqs(pirq, pp)) {
452 		dev_warn(gpio->dev, "no IRQ for port%d\n", pp->idx);
453 		goto err_kfree_pirq;
454 	}
455 
456 	girq = &gc->irq;
457 	girq->handler = handle_bad_irq;
458 	girq->default_type = IRQ_TYPE_NONE;
459 
460 	port->pirq = pirq;
461 
462 	/*
463 	 * Intel ACPI-based platforms mostly have the DesignWare APB GPIO
464 	 * IRQ lane shared between several devices. In that case the parental
465 	 * IRQ has to be handled in the shared way so to be properly delivered
466 	 * to all the connected devices.
467 	 */
468 	if (has_acpi_companion(gpio->dev)) {
469 		girq->num_parents = 0;
470 		girq->parents = NULL;
471 		girq->parent_handler = NULL;
472 
473 		err = devm_request_irq(gpio->dev, pp->irq[0],
474 				       dwapb_irq_handler_mfd,
475 				       IRQF_SHARED, DWAPB_DRIVER_NAME, gpio);
476 		if (err) {
477 			dev_err(gpio->dev, "error requesting IRQ\n");
478 			goto err_kfree_pirq;
479 		}
480 	} else {
481 		girq->num_parents = pirq->nr_irqs;
482 		girq->parents = pirq->irq;
483 		girq->parent_handler_data = gpio;
484 		girq->parent_handler = dwapb_irq_handler;
485 	}
486 
487 	gpio_irq_chip_set_chip(girq, &dwapb_irq_chip);
488 
489 	return;
490 
491 err_kfree_pirq:
492 	devm_kfree(gpio->dev, pirq);
493 }
494 
495 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
496 			       struct dwapb_port_property *pp,
497 			       unsigned int offs)
498 {
499 	struct dwapb_gpio_port *port;
500 	void __iomem *dat, *set, *dirout;
501 	int err;
502 
503 	port = &gpio->ports[offs];
504 	port->gpio = gpio;
505 	port->idx = pp->idx;
506 
507 #ifdef CONFIG_PM_SLEEP
508 	port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL);
509 	if (!port->ctx)
510 		return -ENOMEM;
511 #endif
512 
513 	dat = gpio->regs + GPIO_EXT_PORTA + pp->idx * GPIO_EXT_PORT_STRIDE;
514 	set = gpio->regs + GPIO_SWPORTA_DR + pp->idx * GPIO_SWPORT_DR_STRIDE;
515 	dirout = gpio->regs + GPIO_SWPORTA_DDR + pp->idx * GPIO_SWPORT_DDR_STRIDE;
516 
517 	/* This registers 32 GPIO lines per port */
518 	err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
519 			 NULL, 0);
520 	if (err) {
521 		dev_err(gpio->dev, "failed to init gpio chip for port%d\n",
522 			port->idx);
523 		return err;
524 	}
525 
526 	port->gc.fwnode = pp->fwnode;
527 	port->gc.ngpio = pp->ngpio;
528 	port->gc.base = pp->gpio_base;
529 
530 	/* Only port A support debounce */
531 	if (pp->idx == 0)
532 		port->gc.set_config = dwapb_gpio_set_config;
533 
534 	/* Only port A can provide interrupts in all configurations of the IP */
535 	if (pp->idx == 0)
536 		dwapb_configure_irqs(gpio, port, pp);
537 
538 	err = devm_gpiochip_add_data(gpio->dev, &port->gc, port);
539 	if (err) {
540 		dev_err(gpio->dev, "failed to register gpiochip for port%d\n",
541 			port->idx);
542 		return err;
543 	}
544 
545 	return 0;
546 }
547 
548 static void dwapb_get_irq(struct device *dev, struct fwnode_handle *fwnode,
549 			  struct dwapb_port_property *pp)
550 {
551 	int irq, j;
552 
553 	for (j = 0; j < pp->ngpio; j++) {
554 		if (has_acpi_companion(dev))
555 			irq = platform_get_irq_optional(to_platform_device(dev), j);
556 		else
557 			irq = fwnode_irq_get(fwnode, j);
558 		if (irq > 0)
559 			pp->irq[j] = irq;
560 	}
561 }
562 
563 static struct dwapb_platform_data *dwapb_gpio_get_pdata(struct device *dev)
564 {
565 	struct fwnode_handle *fwnode;
566 	struct dwapb_platform_data *pdata;
567 	struct dwapb_port_property *pp;
568 	int nports;
569 	int i;
570 
571 	nports = device_get_child_node_count(dev);
572 	if (nports == 0)
573 		return ERR_PTR(-ENODEV);
574 
575 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
576 	if (!pdata)
577 		return ERR_PTR(-ENOMEM);
578 
579 	pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL);
580 	if (!pdata->properties)
581 		return ERR_PTR(-ENOMEM);
582 
583 	pdata->nports = nports;
584 
585 	i = 0;
586 	device_for_each_child_node(dev, fwnode)  {
587 		pp = &pdata->properties[i++];
588 		pp->fwnode = fwnode;
589 
590 		if (fwnode_property_read_u32(fwnode, "reg", &pp->idx) ||
591 		    pp->idx >= DWAPB_MAX_PORTS) {
592 			dev_err(dev,
593 				"missing/invalid port index for port%d\n", i);
594 			fwnode_handle_put(fwnode);
595 			return ERR_PTR(-EINVAL);
596 		}
597 
598 		if (fwnode_property_read_u32(fwnode, "ngpios", &pp->ngpio) &&
599 		    fwnode_property_read_u32(fwnode, "snps,nr-gpios", &pp->ngpio)) {
600 			dev_info(dev,
601 				 "failed to get number of gpios for port%d\n",
602 				 i);
603 			pp->ngpio = DWAPB_MAX_GPIOS;
604 		}
605 
606 		pp->gpio_base	= -1;
607 
608 		/* For internal use only, new platforms mustn't exercise this */
609 		if (is_software_node(fwnode))
610 			fwnode_property_read_u32(fwnode, "gpio-base", &pp->gpio_base);
611 
612 		/*
613 		 * Only port A can provide interrupts in all configurations of
614 		 * the IP.
615 		 */
616 		if (pp->idx == 0)
617 			dwapb_get_irq(dev, fwnode, pp);
618 	}
619 
620 	return pdata;
621 }
622 
623 static void dwapb_assert_reset(void *data)
624 {
625 	struct dwapb_gpio *gpio = data;
626 
627 	reset_control_assert(gpio->rst);
628 }
629 
630 static int dwapb_get_reset(struct dwapb_gpio *gpio)
631 {
632 	int err;
633 
634 	gpio->rst = devm_reset_control_get_optional_shared(gpio->dev, NULL);
635 	if (IS_ERR(gpio->rst))
636 		return dev_err_probe(gpio->dev, PTR_ERR(gpio->rst),
637 				     "Cannot get reset descriptor\n");
638 
639 	err = reset_control_deassert(gpio->rst);
640 	if (err) {
641 		dev_err(gpio->dev, "Cannot deassert reset lane\n");
642 		return err;
643 	}
644 
645 	return devm_add_action_or_reset(gpio->dev, dwapb_assert_reset, gpio);
646 }
647 
648 static void dwapb_disable_clks(void *data)
649 {
650 	struct dwapb_gpio *gpio = data;
651 
652 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
653 }
654 
655 static int dwapb_get_clks(struct dwapb_gpio *gpio)
656 {
657 	int err;
658 
659 	/* Optional bus and debounce clocks */
660 	gpio->clks[0].id = "bus";
661 	gpio->clks[1].id = "db";
662 	err = devm_clk_bulk_get_optional(gpio->dev, DWAPB_NR_CLOCKS,
663 					 gpio->clks);
664 	if (err)
665 		return dev_err_probe(gpio->dev, err,
666 				     "Cannot get APB/Debounce clocks\n");
667 
668 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
669 	if (err) {
670 		dev_err(gpio->dev, "Cannot enable APB/Debounce clocks\n");
671 		return err;
672 	}
673 
674 	return devm_add_action_or_reset(gpio->dev, dwapb_disable_clks, gpio);
675 }
676 
677 static const struct of_device_id dwapb_of_match[] = {
678 	{ .compatible = "snps,dw-apb-gpio", .data = (void *)GPIO_REG_OFFSET_V1},
679 	{ .compatible = "apm,xgene-gpio-v2", .data = (void *)GPIO_REG_OFFSET_V2},
680 	{ /* Sentinel */ }
681 };
682 MODULE_DEVICE_TABLE(of, dwapb_of_match);
683 
684 static const struct acpi_device_id dwapb_acpi_match[] = {
685 	{"HISI0181", GPIO_REG_OFFSET_V1},
686 	{"APMC0D07", GPIO_REG_OFFSET_V1},
687 	{"APMC0D81", GPIO_REG_OFFSET_V2},
688 	{ }
689 };
690 MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
691 
692 static int dwapb_gpio_probe(struct platform_device *pdev)
693 {
694 	unsigned int i;
695 	struct dwapb_gpio *gpio;
696 	int err;
697 	struct dwapb_platform_data *pdata;
698 	struct device *dev = &pdev->dev;
699 
700 	pdata = dwapb_gpio_get_pdata(dev);
701 	if (IS_ERR(pdata))
702 		return PTR_ERR(pdata);
703 
704 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
705 	if (!gpio)
706 		return -ENOMEM;
707 
708 	gpio->dev = &pdev->dev;
709 	gpio->nr_ports = pdata->nports;
710 
711 	err = dwapb_get_reset(gpio);
712 	if (err)
713 		return err;
714 
715 	gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports,
716 				   sizeof(*gpio->ports), GFP_KERNEL);
717 	if (!gpio->ports)
718 		return -ENOMEM;
719 
720 	gpio->regs = devm_platform_ioremap_resource(pdev, 0);
721 	if (IS_ERR(gpio->regs))
722 		return PTR_ERR(gpio->regs);
723 
724 	err = dwapb_get_clks(gpio);
725 	if (err)
726 		return err;
727 
728 	gpio->flags = (uintptr_t)device_get_match_data(dev);
729 
730 	for (i = 0; i < gpio->nr_ports; i++) {
731 		err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
732 		if (err)
733 			return err;
734 	}
735 
736 	platform_set_drvdata(pdev, gpio);
737 
738 	return 0;
739 }
740 
741 #ifdef CONFIG_PM_SLEEP
742 static int dwapb_gpio_suspend(struct device *dev)
743 {
744 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
745 	struct gpio_chip *gc	= &gpio->ports[0].gc;
746 	unsigned long flags;
747 	int i;
748 
749 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
750 	for (i = 0; i < gpio->nr_ports; i++) {
751 		unsigned int offset;
752 		unsigned int idx = gpio->ports[i].idx;
753 		struct dwapb_context *ctx = gpio->ports[i].ctx;
754 
755 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
756 		ctx->dir = dwapb_read(gpio, offset);
757 
758 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
759 		ctx->data = dwapb_read(gpio, offset);
760 
761 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
762 		ctx->ext = dwapb_read(gpio, offset);
763 
764 		/* Only port A can provide interrupts */
765 		if (idx == 0) {
766 			ctx->int_mask	= dwapb_read(gpio, GPIO_INTMASK);
767 			ctx->int_en	= dwapb_read(gpio, GPIO_INTEN);
768 			ctx->int_pol	= dwapb_read(gpio, GPIO_INT_POLARITY);
769 			ctx->int_type	= dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
770 			ctx->int_deb	= dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
771 
772 			/* Mask out interrupts */
773 			dwapb_write(gpio, GPIO_INTMASK, ~ctx->wake_en);
774 		}
775 	}
776 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
777 
778 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
779 
780 	return 0;
781 }
782 
783 static int dwapb_gpio_resume(struct device *dev)
784 {
785 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
786 	struct gpio_chip *gc	= &gpio->ports[0].gc;
787 	unsigned long flags;
788 	int i, err;
789 
790 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
791 	if (err) {
792 		dev_err(gpio->dev, "Cannot reenable APB/Debounce clocks\n");
793 		return err;
794 	}
795 
796 	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
797 	for (i = 0; i < gpio->nr_ports; i++) {
798 		unsigned int offset;
799 		unsigned int idx = gpio->ports[i].idx;
800 		struct dwapb_context *ctx = gpio->ports[i].ctx;
801 
802 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
803 		dwapb_write(gpio, offset, ctx->data);
804 
805 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
806 		dwapb_write(gpio, offset, ctx->dir);
807 
808 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
809 		dwapb_write(gpio, offset, ctx->ext);
810 
811 		/* Only port A can provide interrupts */
812 		if (idx == 0) {
813 			dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
814 			dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
815 			dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
816 			dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
817 			dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask);
818 
819 			/* Clear out spurious interrupts */
820 			dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
821 		}
822 	}
823 	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
824 
825 	return 0;
826 }
827 #endif
828 
829 static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
830 			 dwapb_gpio_resume);
831 
832 static struct platform_driver dwapb_gpio_driver = {
833 	.driver		= {
834 		.name	= DWAPB_DRIVER_NAME,
835 		.pm	= &dwapb_gpio_pm_ops,
836 		.of_match_table = dwapb_of_match,
837 		.acpi_match_table = dwapb_acpi_match,
838 	},
839 	.probe		= dwapb_gpio_probe,
840 };
841 
842 module_platform_driver(dwapb_gpio_driver);
843 
844 MODULE_LICENSE("GPL");
845 MODULE_AUTHOR("Jamie Iles");
846 MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
847 MODULE_ALIAS("platform:" DWAPB_DRIVER_NAME);
848