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/clk.h>
12 #include <linux/err.h>
13 #include <linux/gpio/driver.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/ioport.h>
18 #include <linux/irq.h>
19 #include <linux/irqdomain.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_address.h>
23 #include <linux/of_device.h>
24 #include <linux/of_irq.h>
25 #include <linux/platform_device.h>
26 #include <linux/property.h>
27 #include <linux/reset.h>
28 #include <linux/spinlock.h>
29 #include <linux/platform_data/gpio-dwapb.h>
30 #include <linux/slab.h>
31 
32 #include "gpiolib.h"
33 
34 #define GPIO_SWPORTA_DR		0x00
35 #define GPIO_SWPORTA_DDR	0x04
36 #define GPIO_SWPORTB_DR		0x0c
37 #define GPIO_SWPORTB_DDR	0x10
38 #define GPIO_SWPORTC_DR		0x18
39 #define GPIO_SWPORTC_DDR	0x1c
40 #define GPIO_SWPORTD_DR		0x24
41 #define GPIO_SWPORTD_DDR	0x28
42 #define GPIO_INTEN		0x30
43 #define GPIO_INTMASK		0x34
44 #define GPIO_INTTYPE_LEVEL	0x38
45 #define GPIO_INT_POLARITY	0x3c
46 #define GPIO_INTSTATUS		0x40
47 #define GPIO_PORTA_DEBOUNCE	0x48
48 #define GPIO_PORTA_EOI		0x4c
49 #define GPIO_EXT_PORTA		0x50
50 #define GPIO_EXT_PORTB		0x54
51 #define GPIO_EXT_PORTC		0x58
52 #define GPIO_EXT_PORTD		0x5c
53 
54 #define DWAPB_MAX_PORTS		4
55 #define GPIO_EXT_PORT_STRIDE	0x04 /* register stride 32 bits */
56 #define GPIO_SWPORT_DR_STRIDE	0x0c /* register stride 3*32 bits */
57 #define GPIO_SWPORT_DDR_STRIDE	0x0c /* register stride 3*32 bits */
58 
59 #define GPIO_REG_OFFSET_V2	1
60 
61 #define GPIO_INTMASK_V2		0x44
62 #define GPIO_INTTYPE_LEVEL_V2	0x34
63 #define GPIO_INT_POLARITY_V2	0x38
64 #define GPIO_INTSTATUS_V2	0x3c
65 #define GPIO_PORTA_EOI_V2	0x40
66 
67 struct dwapb_gpio;
68 
69 #ifdef CONFIG_PM_SLEEP
70 /* Store GPIO context across system-wide suspend/resume transitions */
71 struct dwapb_context {
72 	u32 data;
73 	u32 dir;
74 	u32 ext;
75 	u32 int_en;
76 	u32 int_mask;
77 	u32 int_type;
78 	u32 int_pol;
79 	u32 int_deb;
80 	u32 wake_en;
81 };
82 #endif
83 
84 struct dwapb_gpio_port {
85 	struct gpio_chip	gc;
86 	bool			is_registered;
87 	struct dwapb_gpio	*gpio;
88 #ifdef CONFIG_PM_SLEEP
89 	struct dwapb_context	*ctx;
90 #endif
91 	unsigned int		idx;
92 };
93 
94 struct dwapb_gpio {
95 	struct	device		*dev;
96 	void __iomem		*regs;
97 	struct dwapb_gpio_port	*ports;
98 	unsigned int		nr_ports;
99 	struct irq_domain	*domain;
100 	unsigned int		flags;
101 	struct reset_control	*rst;
102 	struct clk		*clk;
103 };
104 
gpio_reg_v2_convert(unsigned int offset)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 
gpio_reg_convert(struct dwapb_gpio * gpio,unsigned int offset)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 
dwapb_read(struct dwapb_gpio * gpio,unsigned int offset)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 
dwapb_write(struct dwapb_gpio * gpio,unsigned int offset,u32 val)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 
dwapb_gpio_to_irq(struct gpio_chip * gc,unsigned offset)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 
dwapb_offs_to_port(struct dwapb_gpio * gpio,unsigned int offs)156 static struct dwapb_gpio_port *dwapb_offs_to_port(struct dwapb_gpio *gpio, unsigned int offs)
157 {
158 	struct dwapb_gpio_port *port;
159 	int i;
160 
161 	for (i = 0; i < gpio->nr_ports; i++) {
162 		port = &gpio->ports[i];
163 		if (port->idx == offs / 32)
164 			return port;
165 	}
166 
167 	return NULL;
168 }
169 
dwapb_toggle_trigger(struct dwapb_gpio * gpio,unsigned int offs)170 static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
171 {
172 	struct dwapb_gpio_port *port = dwapb_offs_to_port(gpio, offs);
173 	struct gpio_chip *gc;
174 	u32 pol;
175 	int val;
176 
177 	if (!port)
178 		return;
179 	gc = &port->gc;
180 
181 	pol = dwapb_read(gpio, GPIO_INT_POLARITY);
182 	/* Just read the current value right out of the data register */
183 	val = gc->get(gc, offs % 32);
184 	if (val)
185 		pol &= ~BIT(offs);
186 	else
187 		pol |= BIT(offs);
188 
189 	dwapb_write(gpio, GPIO_INT_POLARITY, pol);
190 }
191 
dwapb_do_irq(struct dwapb_gpio * gpio)192 static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
193 {
194 	u32 irq_status = dwapb_read(gpio, GPIO_INTSTATUS);
195 	u32 ret = irq_status;
196 
197 	while (irq_status) {
198 		int hwirq = fls(irq_status) - 1;
199 		int gpio_irq = irq_find_mapping(gpio->domain, hwirq);
200 
201 		generic_handle_irq(gpio_irq);
202 		irq_status &= ~BIT(hwirq);
203 
204 		if ((irq_get_trigger_type(gpio_irq) & IRQ_TYPE_SENSE_MASK)
205 			== IRQ_TYPE_EDGE_BOTH)
206 			dwapb_toggle_trigger(gpio, hwirq);
207 	}
208 
209 	return ret;
210 }
211 
dwapb_irq_handler(struct irq_desc * desc)212 static void dwapb_irq_handler(struct irq_desc *desc)
213 {
214 	struct dwapb_gpio *gpio = irq_desc_get_handler_data(desc);
215 	struct irq_chip *chip = irq_desc_get_chip(desc);
216 
217 	dwapb_do_irq(gpio);
218 
219 	if (chip->irq_eoi)
220 		chip->irq_eoi(irq_desc_get_irq_data(desc));
221 }
222 
dwapb_irq_enable(struct irq_data * d)223 static void dwapb_irq_enable(struct irq_data *d)
224 {
225 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
226 	struct dwapb_gpio *gpio = igc->private;
227 	struct gpio_chip *gc = &gpio->ports[0].gc;
228 	unsigned long flags;
229 	u32 val;
230 
231 	spin_lock_irqsave(&gc->bgpio_lock, flags);
232 	val = dwapb_read(gpio, GPIO_INTEN);
233 	val |= BIT(d->hwirq);
234 	dwapb_write(gpio, GPIO_INTEN, val);
235 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
236 }
237 
dwapb_irq_disable(struct irq_data * d)238 static void dwapb_irq_disable(struct irq_data *d)
239 {
240 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
241 	struct dwapb_gpio *gpio = igc->private;
242 	struct gpio_chip *gc = &gpio->ports[0].gc;
243 	unsigned long flags;
244 	u32 val;
245 
246 	spin_lock_irqsave(&gc->bgpio_lock, flags);
247 	val = dwapb_read(gpio, GPIO_INTEN);
248 	val &= ~BIT(d->hwirq);
249 	dwapb_write(gpio, GPIO_INTEN, val);
250 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
251 }
252 
dwapb_irq_reqres(struct irq_data * d)253 static int dwapb_irq_reqres(struct irq_data *d)
254 {
255 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
256 	struct dwapb_gpio *gpio = igc->private;
257 	struct gpio_chip *gc = &gpio->ports[0].gc;
258 	int ret;
259 
260 	ret = gpiochip_lock_as_irq(gc, irqd_to_hwirq(d));
261 	if (ret) {
262 		dev_err(gpio->dev, "unable to lock HW IRQ %lu for IRQ\n",
263 			irqd_to_hwirq(d));
264 		return ret;
265 	}
266 	return 0;
267 }
268 
dwapb_irq_relres(struct irq_data * d)269 static void dwapb_irq_relres(struct irq_data *d)
270 {
271 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
272 	struct dwapb_gpio *gpio = igc->private;
273 	struct gpio_chip *gc = &gpio->ports[0].gc;
274 
275 	gpiochip_unlock_as_irq(gc, irqd_to_hwirq(d));
276 }
277 
dwapb_irq_set_type(struct irq_data * d,u32 type)278 static int dwapb_irq_set_type(struct irq_data *d, u32 type)
279 {
280 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
281 	struct dwapb_gpio *gpio = igc->private;
282 	struct gpio_chip *gc = &gpio->ports[0].gc;
283 	int bit = d->hwirq;
284 	unsigned long level, polarity, flags;
285 
286 	if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING |
287 		     IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
288 		return -EINVAL;
289 
290 	spin_lock_irqsave(&gc->bgpio_lock, flags);
291 	level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
292 	polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
293 
294 	switch (type) {
295 	case IRQ_TYPE_EDGE_BOTH:
296 		level |= BIT(bit);
297 		dwapb_toggle_trigger(gpio, bit);
298 		break;
299 	case IRQ_TYPE_EDGE_RISING:
300 		level |= BIT(bit);
301 		polarity |= BIT(bit);
302 		break;
303 	case IRQ_TYPE_EDGE_FALLING:
304 		level |= BIT(bit);
305 		polarity &= ~BIT(bit);
306 		break;
307 	case IRQ_TYPE_LEVEL_HIGH:
308 		level &= ~BIT(bit);
309 		polarity |= BIT(bit);
310 		break;
311 	case IRQ_TYPE_LEVEL_LOW:
312 		level &= ~BIT(bit);
313 		polarity &= ~BIT(bit);
314 		break;
315 	}
316 
317 	irq_setup_alt_chip(d, type);
318 
319 	dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level);
320 	if (type != IRQ_TYPE_EDGE_BOTH)
321 		dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
322 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
323 
324 	return 0;
325 }
326 
327 #ifdef CONFIG_PM_SLEEP
dwapb_irq_set_wake(struct irq_data * d,unsigned int enable)328 static int dwapb_irq_set_wake(struct irq_data *d, unsigned int enable)
329 {
330 	struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
331 	struct dwapb_gpio *gpio = igc->private;
332 	struct dwapb_context *ctx = gpio->ports[0].ctx;
333 
334 	if (enable)
335 		ctx->wake_en |= BIT(d->hwirq);
336 	else
337 		ctx->wake_en &= ~BIT(d->hwirq);
338 
339 	return 0;
340 }
341 #endif
342 
dwapb_gpio_set_debounce(struct gpio_chip * gc,unsigned offset,unsigned debounce)343 static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
344 				   unsigned offset, unsigned debounce)
345 {
346 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
347 	struct dwapb_gpio *gpio = port->gpio;
348 	unsigned long flags, val_deb;
349 	unsigned long mask = BIT(offset);
350 
351 	spin_lock_irqsave(&gc->bgpio_lock, flags);
352 
353 	val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
354 	if (debounce)
355 		dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb | mask);
356 	else
357 		dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb & ~mask);
358 
359 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
360 
361 	return 0;
362 }
363 
dwapb_gpio_set_config(struct gpio_chip * gc,unsigned offset,unsigned long config)364 static int dwapb_gpio_set_config(struct gpio_chip *gc, unsigned offset,
365 				 unsigned long config)
366 {
367 	u32 debounce;
368 
369 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
370 		return -ENOTSUPP;
371 
372 	debounce = pinconf_to_config_argument(config);
373 	return dwapb_gpio_set_debounce(gc, offset, debounce);
374 }
375 
dwapb_irq_handler_mfd(int irq,void * dev_id)376 static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id)
377 {
378 	u32 worked;
379 	struct dwapb_gpio *gpio = dev_id;
380 
381 	worked = dwapb_do_irq(gpio);
382 
383 	return worked ? IRQ_HANDLED : IRQ_NONE;
384 }
385 
dwapb_configure_irqs(struct dwapb_gpio * gpio,struct dwapb_gpio_port * port,struct dwapb_port_property * pp)386 static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
387 				 struct dwapb_gpio_port *port,
388 				 struct dwapb_port_property *pp)
389 {
390 	struct gpio_chip *gc = &port->gc;
391 	struct fwnode_handle  *fwnode = pp->fwnode;
392 	struct irq_chip_generic	*irq_gc = NULL;
393 	unsigned int hwirq, ngpio = gc->ngpio;
394 	struct irq_chip_type *ct;
395 	int err, i;
396 
397 	gpio->domain = irq_domain_create_linear(fwnode, ngpio,
398 						 &irq_generic_chip_ops, gpio);
399 	if (!gpio->domain)
400 		return;
401 
402 	err = irq_alloc_domain_generic_chips(gpio->domain, ngpio, 2,
403 					     "gpio-dwapb", handle_level_irq,
404 					     IRQ_NOREQUEST, 0,
405 					     IRQ_GC_INIT_NESTED_LOCK);
406 	if (err) {
407 		dev_info(gpio->dev, "irq_alloc_domain_generic_chips failed\n");
408 		irq_domain_remove(gpio->domain);
409 		gpio->domain = NULL;
410 		return;
411 	}
412 
413 	irq_gc = irq_get_domain_generic_chip(gpio->domain, 0);
414 	if (!irq_gc) {
415 		irq_domain_remove(gpio->domain);
416 		gpio->domain = NULL;
417 		return;
418 	}
419 
420 	irq_gc->reg_base = gpio->regs;
421 	irq_gc->private = gpio;
422 
423 	for (i = 0; i < 2; i++) {
424 		ct = &irq_gc->chip_types[i];
425 		ct->chip.irq_ack = irq_gc_ack_set_bit;
426 		ct->chip.irq_mask = irq_gc_mask_set_bit;
427 		ct->chip.irq_unmask = irq_gc_mask_clr_bit;
428 		ct->chip.irq_set_type = dwapb_irq_set_type;
429 		ct->chip.irq_enable = dwapb_irq_enable;
430 		ct->chip.irq_disable = dwapb_irq_disable;
431 		ct->chip.irq_request_resources = dwapb_irq_reqres;
432 		ct->chip.irq_release_resources = dwapb_irq_relres;
433 #ifdef CONFIG_PM_SLEEP
434 		ct->chip.irq_set_wake = dwapb_irq_set_wake;
435 #endif
436 		ct->regs.ack = gpio_reg_convert(gpio, GPIO_PORTA_EOI);
437 		ct->regs.mask = gpio_reg_convert(gpio, GPIO_INTMASK);
438 		ct->type = IRQ_TYPE_LEVEL_MASK;
439 	}
440 
441 	irq_gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK;
442 	irq_gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH;
443 	irq_gc->chip_types[1].handler = handle_edge_irq;
444 
445 	if (!pp->irq_shared) {
446 		int i;
447 
448 		for (i = 0; i < pp->ngpio; i++) {
449 			if (pp->irq[i] >= 0)
450 				irq_set_chained_handler_and_data(pp->irq[i],
451 						dwapb_irq_handler, gpio);
452 		}
453 	} else {
454 		/*
455 		 * Request a shared IRQ since where MFD would have devices
456 		 * using the same irq pin
457 		 */
458 		err = devm_request_irq(gpio->dev, pp->irq[0],
459 				       dwapb_irq_handler_mfd,
460 				       IRQF_SHARED, "gpio-dwapb-mfd", gpio);
461 		if (err) {
462 			dev_err(gpio->dev, "error requesting IRQ\n");
463 			irq_domain_remove(gpio->domain);
464 			gpio->domain = NULL;
465 			return;
466 		}
467 	}
468 
469 	for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
470 		irq_create_mapping(gpio->domain, hwirq);
471 
472 	port->gc.to_irq = dwapb_gpio_to_irq;
473 }
474 
dwapb_irq_teardown(struct dwapb_gpio * gpio)475 static void dwapb_irq_teardown(struct dwapb_gpio *gpio)
476 {
477 	struct dwapb_gpio_port *port = &gpio->ports[0];
478 	struct gpio_chip *gc = &port->gc;
479 	unsigned int ngpio = gc->ngpio;
480 	irq_hw_number_t hwirq;
481 
482 	if (!gpio->domain)
483 		return;
484 
485 	for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
486 		irq_dispose_mapping(irq_find_mapping(gpio->domain, hwirq));
487 
488 	irq_domain_remove(gpio->domain);
489 	gpio->domain = NULL;
490 }
491 
dwapb_gpio_add_port(struct dwapb_gpio * gpio,struct dwapb_port_property * pp,unsigned int offs)492 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
493 			       struct dwapb_port_property *pp,
494 			       unsigned int offs)
495 {
496 	struct dwapb_gpio_port *port;
497 	void __iomem *dat, *set, *dirout;
498 	int err;
499 
500 	port = &gpio->ports[offs];
501 	port->gpio = gpio;
502 	port->idx = pp->idx;
503 
504 #ifdef CONFIG_PM_SLEEP
505 	port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL);
506 	if (!port->ctx)
507 		return -ENOMEM;
508 #endif
509 
510 	dat = gpio->regs + GPIO_EXT_PORTA + (pp->idx * GPIO_EXT_PORT_STRIDE);
511 	set = gpio->regs + GPIO_SWPORTA_DR + (pp->idx * GPIO_SWPORT_DR_STRIDE);
512 	dirout = gpio->regs + GPIO_SWPORTA_DDR +
513 		(pp->idx * GPIO_SWPORT_DDR_STRIDE);
514 
515 	/* This registers 32 GPIO lines per port */
516 	err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
517 			 NULL, 0);
518 	if (err) {
519 		dev_err(gpio->dev, "failed to init gpio chip for port%d\n",
520 			port->idx);
521 		return err;
522 	}
523 
524 #ifdef CONFIG_OF_GPIO
525 	port->gc.of_node = to_of_node(pp->fwnode);
526 #endif
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 	if (pp->has_irq)
535 		dwapb_configure_irqs(gpio, port, pp);
536 
537 	err = gpiochip_add_data(&port->gc, port);
538 	if (err)
539 		dev_err(gpio->dev, "failed to register gpiochip for port%d\n",
540 			port->idx);
541 	else
542 		port->is_registered = true;
543 
544 	/* Add GPIO-signaled ACPI event support */
545 	if (pp->has_irq)
546 		acpi_gpiochip_request_interrupts(&port->gc);
547 
548 	return err;
549 }
550 
dwapb_gpio_unregister(struct dwapb_gpio * gpio)551 static void dwapb_gpio_unregister(struct dwapb_gpio *gpio)
552 {
553 	unsigned int m;
554 
555 	for (m = 0; m < gpio->nr_ports; ++m)
556 		if (gpio->ports[m].is_registered)
557 			gpiochip_remove(&gpio->ports[m].gc);
558 }
559 
560 static struct dwapb_platform_data *
dwapb_gpio_get_pdata(struct device * dev)561 dwapb_gpio_get_pdata(struct device *dev)
562 {
563 	struct fwnode_handle *fwnode;
564 	struct dwapb_platform_data *pdata;
565 	struct dwapb_port_property *pp;
566 	int nports;
567 	int i, j;
568 
569 	nports = device_get_child_node_count(dev);
570 	if (nports == 0)
571 		return ERR_PTR(-ENODEV);
572 
573 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
574 	if (!pdata)
575 		return ERR_PTR(-ENOMEM);
576 
577 	pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL);
578 	if (!pdata->properties)
579 		return ERR_PTR(-ENOMEM);
580 
581 	pdata->nports = nports;
582 
583 	i = 0;
584 	device_for_each_child_node(dev, fwnode)  {
585 		struct device_node *np = NULL;
586 
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, "snps,nr-gpios",
599 					 &pp->ngpio)) {
600 			dev_info(dev,
601 				 "failed to get number of gpios for port%d\n",
602 				 i);
603 			pp->ngpio = 32;
604 		}
605 
606 		pp->irq_shared	= false;
607 		pp->gpio_base	= -1;
608 
609 		/*
610 		 * Only port A can provide interrupts in all configurations of
611 		 * the IP.
612 		 */
613 		if (pp->idx != 0)
614 			continue;
615 
616 		if (dev->of_node && fwnode_property_read_bool(fwnode,
617 						  "interrupt-controller")) {
618 			np = to_of_node(fwnode);
619 		}
620 
621 		for (j = 0; j < pp->ngpio; j++) {
622 			pp->irq[j] = -ENXIO;
623 
624 			if (np)
625 				pp->irq[j] = of_irq_get(np, j);
626 			else if (has_acpi_companion(dev))
627 				pp->irq[j] = platform_get_irq(to_platform_device(dev), j);
628 
629 			if (pp->irq[j] >= 0)
630 				pp->has_irq = true;
631 		}
632 
633 		if (!pp->has_irq)
634 			dev_warn(dev, "no irq for port%d\n", pp->idx);
635 	}
636 
637 	return pdata;
638 }
639 
640 static const struct of_device_id dwapb_of_match[] = {
641 	{ .compatible = "snps,dw-apb-gpio", .data = (void *)0},
642 	{ .compatible = "apm,xgene-gpio-v2", .data = (void *)GPIO_REG_OFFSET_V2},
643 	{ /* Sentinel */ }
644 };
645 MODULE_DEVICE_TABLE(of, dwapb_of_match);
646 
647 static const struct acpi_device_id dwapb_acpi_match[] = {
648 	{"HISI0181", 0},
649 	{"APMC0D07", 0},
650 	{"APMC0D81", GPIO_REG_OFFSET_V2},
651 	{ }
652 };
653 MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
654 
dwapb_gpio_probe(struct platform_device * pdev)655 static int dwapb_gpio_probe(struct platform_device *pdev)
656 {
657 	unsigned int i;
658 	struct resource *res;
659 	struct dwapb_gpio *gpio;
660 	int err;
661 	struct device *dev = &pdev->dev;
662 	struct dwapb_platform_data *pdata = dev_get_platdata(dev);
663 
664 	if (!pdata) {
665 		pdata = dwapb_gpio_get_pdata(dev);
666 		if (IS_ERR(pdata))
667 			return PTR_ERR(pdata);
668 	}
669 
670 	if (!pdata->nports)
671 		return -ENODEV;
672 
673 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
674 	if (!gpio)
675 		return -ENOMEM;
676 
677 	gpio->dev = &pdev->dev;
678 	gpio->nr_ports = pdata->nports;
679 
680 	gpio->rst = devm_reset_control_get_optional_shared(dev, NULL);
681 	if (IS_ERR(gpio->rst))
682 		return PTR_ERR(gpio->rst);
683 
684 	reset_control_deassert(gpio->rst);
685 
686 	gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports,
687 				   sizeof(*gpio->ports), GFP_KERNEL);
688 	if (!gpio->ports)
689 		return -ENOMEM;
690 
691 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
692 	gpio->regs = devm_ioremap_resource(&pdev->dev, res);
693 	if (IS_ERR(gpio->regs))
694 		return PTR_ERR(gpio->regs);
695 
696 	/* Optional bus clock */
697 	gpio->clk = devm_clk_get(&pdev->dev, "bus");
698 	if (!IS_ERR(gpio->clk)) {
699 		err = clk_prepare_enable(gpio->clk);
700 		if (err) {
701 			dev_info(&pdev->dev, "Cannot enable clock\n");
702 			return err;
703 		}
704 	}
705 
706 	gpio->flags = 0;
707 	if (dev->of_node) {
708 		gpio->flags = (uintptr_t)of_device_get_match_data(dev);
709 	} else if (has_acpi_companion(dev)) {
710 		const struct acpi_device_id *acpi_id;
711 
712 		acpi_id = acpi_match_device(dwapb_acpi_match, dev);
713 		if (acpi_id) {
714 			if (acpi_id->driver_data)
715 				gpio->flags = acpi_id->driver_data;
716 		}
717 	}
718 
719 	for (i = 0; i < gpio->nr_ports; i++) {
720 		err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
721 		if (err)
722 			goto out_unregister;
723 	}
724 	platform_set_drvdata(pdev, gpio);
725 
726 	return 0;
727 
728 out_unregister:
729 	dwapb_gpio_unregister(gpio);
730 	dwapb_irq_teardown(gpio);
731 	clk_disable_unprepare(gpio->clk);
732 
733 	return err;
734 }
735 
dwapb_gpio_remove(struct platform_device * pdev)736 static int dwapb_gpio_remove(struct platform_device *pdev)
737 {
738 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
739 
740 	dwapb_gpio_unregister(gpio);
741 	dwapb_irq_teardown(gpio);
742 	reset_control_assert(gpio->rst);
743 	clk_disable_unprepare(gpio->clk);
744 
745 	return 0;
746 }
747 
748 #ifdef CONFIG_PM_SLEEP
dwapb_gpio_suspend(struct device * dev)749 static int dwapb_gpio_suspend(struct device *dev)
750 {
751 	struct platform_device *pdev = to_platform_device(dev);
752 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
753 	struct gpio_chip *gc	= &gpio->ports[0].gc;
754 	unsigned long flags;
755 	int i;
756 
757 	spin_lock_irqsave(&gc->bgpio_lock, flags);
758 	for (i = 0; i < gpio->nr_ports; i++) {
759 		unsigned int offset;
760 		unsigned int idx = gpio->ports[i].idx;
761 		struct dwapb_context *ctx = gpio->ports[i].ctx;
762 
763 		BUG_ON(!ctx);
764 
765 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
766 		ctx->dir = dwapb_read(gpio, offset);
767 
768 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
769 		ctx->data = dwapb_read(gpio, offset);
770 
771 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
772 		ctx->ext = dwapb_read(gpio, offset);
773 
774 		/* Only port A can provide interrupts */
775 		if (idx == 0) {
776 			ctx->int_mask	= dwapb_read(gpio, GPIO_INTMASK);
777 			ctx->int_en	= dwapb_read(gpio, GPIO_INTEN);
778 			ctx->int_pol	= dwapb_read(gpio, GPIO_INT_POLARITY);
779 			ctx->int_type	= dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
780 			ctx->int_deb	= dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
781 
782 			/* Mask out interrupts */
783 			dwapb_write(gpio, GPIO_INTMASK,
784 				    0xffffffff & ~ctx->wake_en);
785 		}
786 	}
787 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
788 
789 	clk_disable_unprepare(gpio->clk);
790 
791 	return 0;
792 }
793 
dwapb_gpio_resume(struct device * dev)794 static int dwapb_gpio_resume(struct device *dev)
795 {
796 	struct platform_device *pdev = to_platform_device(dev);
797 	struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
798 	struct gpio_chip *gc	= &gpio->ports[0].gc;
799 	unsigned long flags;
800 	int i;
801 
802 	if (!IS_ERR(gpio->clk))
803 		clk_prepare_enable(gpio->clk);
804 
805 	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 		BUG_ON(!ctx);
812 
813 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
814 		dwapb_write(gpio, offset, ctx->data);
815 
816 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
817 		dwapb_write(gpio, offset, ctx->dir);
818 
819 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
820 		dwapb_write(gpio, offset, ctx->ext);
821 
822 		/* Only port A can provide interrupts */
823 		if (idx == 0) {
824 			dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
825 			dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
826 			dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
827 			dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
828 			dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask);
829 
830 			/* Clear out spurious interrupts */
831 			dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
832 		}
833 	}
834 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
835 
836 	return 0;
837 }
838 #endif
839 
840 static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
841 			 dwapb_gpio_resume);
842 
843 static struct platform_driver dwapb_gpio_driver = {
844 	.driver		= {
845 		.name	= "gpio-dwapb",
846 		.pm	= &dwapb_gpio_pm_ops,
847 		.of_match_table = of_match_ptr(dwapb_of_match),
848 		.acpi_match_table = ACPI_PTR(dwapb_acpi_match),
849 	},
850 	.probe		= dwapb_gpio_probe,
851 	.remove		= dwapb_gpio_remove,
852 };
853 
854 module_platform_driver(dwapb_gpio_driver);
855 
856 MODULE_LICENSE("GPL");
857 MODULE_AUTHOR("Jamie Iles");
858 MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
859