xref: /linux/drivers/gpio/gpio-dwapb.c (revision 662f11d55ffd02933e1bd275d732b97eddccf870)
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/of.h>
19 #include <linux/platform_device.h>
20 #include <linux/property.h>
21 #include <linux/reset.h>
22 #include <linux/slab.h>
23 #include <linux/spinlock.h>
24 
25 #include "gpiolib.h"
26 #include "gpiolib-acpi.h"
27 
28 #define GPIO_SWPORTA_DR		0x00
29 #define GPIO_SWPORTA_DDR	0x04
30 #define GPIO_SWPORTB_DR		0x0c
31 #define GPIO_SWPORTB_DDR	0x10
32 #define GPIO_SWPORTC_DR		0x18
33 #define GPIO_SWPORTC_DDR	0x1c
34 #define GPIO_SWPORTD_DR		0x24
35 #define GPIO_SWPORTD_DDR	0x28
36 #define GPIO_INTEN		0x30
37 #define GPIO_INTMASK		0x34
38 #define GPIO_INTTYPE_LEVEL	0x38
39 #define GPIO_INT_POLARITY	0x3c
40 #define GPIO_INTSTATUS		0x40
41 #define GPIO_PORTA_DEBOUNCE	0x48
42 #define GPIO_PORTA_EOI		0x4c
43 #define GPIO_EXT_PORTA		0x50
44 #define GPIO_EXT_PORTB		0x54
45 #define GPIO_EXT_PORTC		0x58
46 #define GPIO_EXT_PORTD		0x5c
47 
48 #define DWAPB_DRIVER_NAME	"gpio-dwapb"
49 #define DWAPB_MAX_PORTS		4
50 #define DWAPB_MAX_GPIOS		32
51 
52 #define GPIO_EXT_PORT_STRIDE	0x04 /* register stride 32 bits */
53 #define GPIO_SWPORT_DR_STRIDE	0x0c /* register stride 3*32 bits */
54 #define GPIO_SWPORT_DDR_STRIDE	0x0c /* register stride 3*32 bits */
55 
56 #define GPIO_REG_OFFSET_V2	1
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 	struct irq_chip		irqchip;
98 	unsigned int		nr_irqs;
99 	unsigned int		irq[DWAPB_MAX_GPIOS];
100 };
101 
102 struct dwapb_gpio_port {
103 	struct gpio_chip	gc;
104 	struct dwapb_gpio_port_irqchip *pirq;
105 	struct dwapb_gpio	*gpio;
106 #ifdef CONFIG_PM_SLEEP
107 	struct dwapb_context	*ctx;
108 #endif
109 	unsigned int		idx;
110 };
111 #define to_dwapb_gpio(_gc) \
112 	(container_of(_gc, struct dwapb_gpio_port, gc)->gpio)
113 
114 struct dwapb_gpio {
115 	struct	device		*dev;
116 	void __iomem		*regs;
117 	struct dwapb_gpio_port	*ports;
118 	unsigned int		nr_ports;
119 	unsigned int		flags;
120 	struct reset_control	*rst;
121 	struct clk_bulk_data	clks[DWAPB_NR_CLOCKS];
122 };
123 
124 static inline u32 gpio_reg_v2_convert(unsigned int offset)
125 {
126 	switch (offset) {
127 	case GPIO_INTMASK:
128 		return GPIO_INTMASK_V2;
129 	case GPIO_INTTYPE_LEVEL:
130 		return GPIO_INTTYPE_LEVEL_V2;
131 	case GPIO_INT_POLARITY:
132 		return GPIO_INT_POLARITY_V2;
133 	case GPIO_INTSTATUS:
134 		return GPIO_INTSTATUS_V2;
135 	case GPIO_PORTA_EOI:
136 		return GPIO_PORTA_EOI_V2;
137 	}
138 
139 	return offset;
140 }
141 
142 static inline u32 gpio_reg_convert(struct dwapb_gpio *gpio, unsigned int offset)
143 {
144 	if (gpio->flags & GPIO_REG_OFFSET_V2)
145 		return gpio_reg_v2_convert(offset);
146 
147 	return offset;
148 }
149 
150 static inline u32 dwapb_read(struct dwapb_gpio *gpio, unsigned int offset)
151 {
152 	struct gpio_chip *gc	= &gpio->ports[0].gc;
153 	void __iomem *reg_base	= gpio->regs;
154 
155 	return gc->read_reg(reg_base + gpio_reg_convert(gpio, offset));
156 }
157 
158 static inline void dwapb_write(struct dwapb_gpio *gpio, unsigned int offset,
159 			       u32 val)
160 {
161 	struct gpio_chip *gc	= &gpio->ports[0].gc;
162 	void __iomem *reg_base	= gpio->regs;
163 
164 	gc->write_reg(reg_base + gpio_reg_convert(gpio, offset), val);
165 }
166 
167 static struct dwapb_gpio_port *dwapb_offs_to_port(struct dwapb_gpio *gpio, unsigned int offs)
168 {
169 	struct dwapb_gpio_port *port;
170 	int i;
171 
172 	for (i = 0; i < gpio->nr_ports; i++) {
173 		port = &gpio->ports[i];
174 		if (port->idx == offs / DWAPB_MAX_GPIOS)
175 			return port;
176 	}
177 
178 	return NULL;
179 }
180 
181 static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
182 {
183 	struct dwapb_gpio_port *port = dwapb_offs_to_port(gpio, offs);
184 	struct gpio_chip *gc;
185 	u32 pol;
186 	int val;
187 
188 	if (!port)
189 		return;
190 	gc = &port->gc;
191 
192 	pol = dwapb_read(gpio, GPIO_INT_POLARITY);
193 	/* Just read the current value right out of the data register */
194 	val = gc->get(gc, offs % DWAPB_MAX_GPIOS);
195 	if (val)
196 		pol &= ~BIT(offs);
197 	else
198 		pol |= BIT(offs);
199 
200 	dwapb_write(gpio, GPIO_INT_POLARITY, pol);
201 }
202 
203 static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
204 {
205 	struct gpio_chip *gc = &gpio->ports[0].gc;
206 	unsigned long irq_status;
207 	irq_hw_number_t hwirq;
208 
209 	irq_status = dwapb_read(gpio, GPIO_INTSTATUS);
210 	for_each_set_bit(hwirq, &irq_status, DWAPB_MAX_GPIOS) {
211 		int gpio_irq = irq_find_mapping(gc->irq.domain, hwirq);
212 		u32 irq_type = irq_get_trigger_type(gpio_irq);
213 
214 		generic_handle_irq(gpio_irq);
215 
216 		if ((irq_type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
217 			dwapb_toggle_trigger(gpio, hwirq);
218 	}
219 
220 	return irq_status;
221 }
222 
223 static void dwapb_irq_handler(struct irq_desc *desc)
224 {
225 	struct dwapb_gpio *gpio = irq_desc_get_handler_data(desc);
226 	struct irq_chip *chip = irq_desc_get_chip(desc);
227 
228 	chained_irq_enter(chip, desc);
229 	dwapb_do_irq(gpio);
230 	chained_irq_exit(chip, desc);
231 }
232 
233 static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id)
234 {
235 	return IRQ_RETVAL(dwapb_do_irq(dev_id));
236 }
237 
238 static void dwapb_irq_ack(struct irq_data *d)
239 {
240 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
241 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
242 	u32 val = BIT(irqd_to_hwirq(d));
243 	unsigned long flags;
244 
245 	spin_lock_irqsave(&gc->bgpio_lock, flags);
246 	dwapb_write(gpio, GPIO_PORTA_EOI, val);
247 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
248 }
249 
250 static void dwapb_irq_mask(struct irq_data *d)
251 {
252 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
253 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
254 	unsigned long flags;
255 	u32 val;
256 
257 	spin_lock_irqsave(&gc->bgpio_lock, flags);
258 	val = dwapb_read(gpio, GPIO_INTMASK) | BIT(irqd_to_hwirq(d));
259 	dwapb_write(gpio, GPIO_INTMASK, val);
260 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
261 }
262 
263 static void dwapb_irq_unmask(struct irq_data *d)
264 {
265 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
266 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
267 	unsigned long flags;
268 	u32 val;
269 
270 	spin_lock_irqsave(&gc->bgpio_lock, flags);
271 	val = dwapb_read(gpio, GPIO_INTMASK) & ~BIT(irqd_to_hwirq(d));
272 	dwapb_write(gpio, GPIO_INTMASK, val);
273 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
274 }
275 
276 static void dwapb_irq_enable(struct irq_data *d)
277 {
278 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
279 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
280 	unsigned long flags;
281 	u32 val;
282 
283 	spin_lock_irqsave(&gc->bgpio_lock, flags);
284 	val = dwapb_read(gpio, GPIO_INTEN);
285 	val |= BIT(irqd_to_hwirq(d));
286 	dwapb_write(gpio, GPIO_INTEN, val);
287 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
288 }
289 
290 static void dwapb_irq_disable(struct irq_data *d)
291 {
292 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
293 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
294 	unsigned long flags;
295 	u32 val;
296 
297 	spin_lock_irqsave(&gc->bgpio_lock, flags);
298 	val = dwapb_read(gpio, GPIO_INTEN);
299 	val &= ~BIT(irqd_to_hwirq(d));
300 	dwapb_write(gpio, GPIO_INTEN, val);
301 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
302 }
303 
304 static int dwapb_irq_set_type(struct irq_data *d, u32 type)
305 {
306 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
307 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
308 	irq_hw_number_t bit = irqd_to_hwirq(d);
309 	unsigned long level, polarity, flags;
310 
311 	spin_lock_irqsave(&gc->bgpio_lock, flags);
312 	level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
313 	polarity = dwapb_read(gpio, GPIO_INT_POLARITY);
314 
315 	switch (type) {
316 	case IRQ_TYPE_EDGE_BOTH:
317 		level |= BIT(bit);
318 		dwapb_toggle_trigger(gpio, bit);
319 		break;
320 	case IRQ_TYPE_EDGE_RISING:
321 		level |= BIT(bit);
322 		polarity |= BIT(bit);
323 		break;
324 	case IRQ_TYPE_EDGE_FALLING:
325 		level |= BIT(bit);
326 		polarity &= ~BIT(bit);
327 		break;
328 	case IRQ_TYPE_LEVEL_HIGH:
329 		level &= ~BIT(bit);
330 		polarity |= BIT(bit);
331 		break;
332 	case IRQ_TYPE_LEVEL_LOW:
333 		level &= ~BIT(bit);
334 		polarity &= ~BIT(bit);
335 		break;
336 	}
337 
338 	if (type & IRQ_TYPE_LEVEL_MASK)
339 		irq_set_handler_locked(d, handle_level_irq);
340 	else if (type & IRQ_TYPE_EDGE_BOTH)
341 		irq_set_handler_locked(d, handle_edge_irq);
342 
343 	dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level);
344 	if (type != IRQ_TYPE_EDGE_BOTH)
345 		dwapb_write(gpio, GPIO_INT_POLARITY, polarity);
346 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
347 
348 	return 0;
349 }
350 
351 #ifdef CONFIG_PM_SLEEP
352 static int dwapb_irq_set_wake(struct irq_data *d, unsigned int enable)
353 {
354 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
355 	struct dwapb_gpio *gpio = to_dwapb_gpio(gc);
356 	struct dwapb_context *ctx = gpio->ports[0].ctx;
357 	irq_hw_number_t bit = irqd_to_hwirq(d);
358 
359 	if (enable)
360 		ctx->wake_en |= BIT(bit);
361 	else
362 		ctx->wake_en &= ~BIT(bit);
363 
364 	return 0;
365 }
366 #endif
367 
368 static int dwapb_gpio_set_debounce(struct gpio_chip *gc,
369 				   unsigned offset, unsigned debounce)
370 {
371 	struct dwapb_gpio_port *port = gpiochip_get_data(gc);
372 	struct dwapb_gpio *gpio = port->gpio;
373 	unsigned long flags, val_deb;
374 	unsigned long mask = BIT(offset);
375 
376 	spin_lock_irqsave(&gc->bgpio_lock, flags);
377 
378 	val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
379 	if (debounce)
380 		val_deb |= mask;
381 	else
382 		val_deb &= ~mask;
383 	dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb);
384 
385 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
386 
387 	return 0;
388 }
389 
390 static int dwapb_gpio_set_config(struct gpio_chip *gc, unsigned offset,
391 				 unsigned long config)
392 {
393 	u32 debounce;
394 
395 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
396 		return -ENOTSUPP;
397 
398 	debounce = pinconf_to_config_argument(config);
399 	return dwapb_gpio_set_debounce(gc, offset, debounce);
400 }
401 
402 static int dwapb_convert_irqs(struct dwapb_gpio_port_irqchip *pirq,
403 			      struct dwapb_port_property *pp)
404 {
405 	int i;
406 
407 	/* Group all available IRQs into an array of parental IRQs. */
408 	for (i = 0; i < pp->ngpio; ++i) {
409 		if (!pp->irq[i])
410 			continue;
411 
412 		pirq->irq[pirq->nr_irqs++] = pp->irq[i];
413 	}
414 
415 	return pirq->nr_irqs ? 0 : -ENOENT;
416 }
417 
418 static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
419 				 struct dwapb_gpio_port *port,
420 				 struct dwapb_port_property *pp)
421 {
422 	struct dwapb_gpio_port_irqchip *pirq;
423 	struct gpio_chip *gc = &port->gc;
424 	struct gpio_irq_chip *girq;
425 	int err;
426 
427 	pirq = devm_kzalloc(gpio->dev, sizeof(*pirq), GFP_KERNEL);
428 	if (!pirq)
429 		return;
430 
431 	if (dwapb_convert_irqs(pirq, pp)) {
432 		dev_warn(gpio->dev, "no IRQ for port%d\n", pp->idx);
433 		goto err_kfree_pirq;
434 	}
435 
436 	girq = &gc->irq;
437 	girq->handler = handle_bad_irq;
438 	girq->default_type = IRQ_TYPE_NONE;
439 
440 	port->pirq = pirq;
441 	pirq->irqchip.name = DWAPB_DRIVER_NAME;
442 	pirq->irqchip.irq_ack = dwapb_irq_ack;
443 	pirq->irqchip.irq_mask = dwapb_irq_mask;
444 	pirq->irqchip.irq_unmask = dwapb_irq_unmask;
445 	pirq->irqchip.irq_set_type = dwapb_irq_set_type;
446 	pirq->irqchip.irq_enable = dwapb_irq_enable;
447 	pirq->irqchip.irq_disable = dwapb_irq_disable;
448 #ifdef CONFIG_PM_SLEEP
449 	pirq->irqchip.irq_set_wake = dwapb_irq_set_wake;
450 #endif
451 
452 	/*
453 	 * Intel ACPI-based platforms mostly have the DesignWare APB GPIO
454 	 * IRQ lane shared between several devices. In that case the parental
455 	 * IRQ has to be handled in the shared way so to be properly delivered
456 	 * to all the connected devices.
457 	 */
458 	if (has_acpi_companion(gpio->dev)) {
459 		girq->num_parents = 0;
460 		girq->parents = NULL;
461 		girq->parent_handler = NULL;
462 
463 		err = devm_request_irq(gpio->dev, pp->irq[0],
464 				       dwapb_irq_handler_mfd,
465 				       IRQF_SHARED, DWAPB_DRIVER_NAME, gpio);
466 		if (err) {
467 			dev_err(gpio->dev, "error requesting IRQ\n");
468 			goto err_kfree_pirq;
469 		}
470 	} else {
471 		girq->num_parents = pirq->nr_irqs;
472 		girq->parents = pirq->irq;
473 		girq->parent_handler_data = gpio;
474 		girq->parent_handler = dwapb_irq_handler;
475 	}
476 
477 	girq->chip = &pirq->irqchip;
478 
479 	return;
480 
481 err_kfree_pirq:
482 	devm_kfree(gpio->dev, pirq);
483 }
484 
485 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
486 			       struct dwapb_port_property *pp,
487 			       unsigned int offs)
488 {
489 	struct dwapb_gpio_port *port;
490 	void __iomem *dat, *set, *dirout;
491 	int err;
492 
493 	port = &gpio->ports[offs];
494 	port->gpio = gpio;
495 	port->idx = pp->idx;
496 
497 #ifdef CONFIG_PM_SLEEP
498 	port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL);
499 	if (!port->ctx)
500 		return -ENOMEM;
501 #endif
502 
503 	dat = gpio->regs + GPIO_EXT_PORTA + pp->idx * GPIO_EXT_PORT_STRIDE;
504 	set = gpio->regs + GPIO_SWPORTA_DR + pp->idx * GPIO_SWPORT_DR_STRIDE;
505 	dirout = gpio->regs + GPIO_SWPORTA_DDR + pp->idx * GPIO_SWPORT_DDR_STRIDE;
506 
507 	/* This registers 32 GPIO lines per port */
508 	err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
509 			 NULL, 0);
510 	if (err) {
511 		dev_err(gpio->dev, "failed to init gpio chip for port%d\n",
512 			port->idx);
513 		return err;
514 	}
515 
516 #ifdef CONFIG_OF_GPIO
517 	port->gc.of_node = to_of_node(pp->fwnode);
518 #endif
519 	port->gc.ngpio = pp->ngpio;
520 	port->gc.base = pp->gpio_base;
521 
522 	/* Only port A support debounce */
523 	if (pp->idx == 0)
524 		port->gc.set_config = dwapb_gpio_set_config;
525 
526 	/* Only port A can provide interrupts in all configurations of the IP */
527 	if (pp->idx == 0)
528 		dwapb_configure_irqs(gpio, port, pp);
529 
530 	err = devm_gpiochip_add_data(gpio->dev, &port->gc, port);
531 	if (err) {
532 		dev_err(gpio->dev, "failed to register gpiochip for port%d\n",
533 			port->idx);
534 		return err;
535 	}
536 
537 	return 0;
538 }
539 
540 static void dwapb_get_irq(struct device *dev, struct fwnode_handle *fwnode,
541 			  struct dwapb_port_property *pp)
542 {
543 	int irq, j;
544 
545 	for (j = 0; j < pp->ngpio; j++) {
546 		if (has_acpi_companion(dev))
547 			irq = platform_get_irq_optional(to_platform_device(dev), j);
548 		else
549 			irq = fwnode_irq_get(fwnode, j);
550 		if (irq > 0)
551 			pp->irq[j] = irq;
552 	}
553 }
554 
555 static struct dwapb_platform_data *dwapb_gpio_get_pdata(struct device *dev)
556 {
557 	struct fwnode_handle *fwnode;
558 	struct dwapb_platform_data *pdata;
559 	struct dwapb_port_property *pp;
560 	int nports;
561 	int i;
562 
563 	nports = device_get_child_node_count(dev);
564 	if (nports == 0)
565 		return ERR_PTR(-ENODEV);
566 
567 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
568 	if (!pdata)
569 		return ERR_PTR(-ENOMEM);
570 
571 	pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL);
572 	if (!pdata->properties)
573 		return ERR_PTR(-ENOMEM);
574 
575 	pdata->nports = nports;
576 
577 	i = 0;
578 	device_for_each_child_node(dev, fwnode)  {
579 		pp = &pdata->properties[i++];
580 		pp->fwnode = fwnode;
581 
582 		if (fwnode_property_read_u32(fwnode, "reg", &pp->idx) ||
583 		    pp->idx >= DWAPB_MAX_PORTS) {
584 			dev_err(dev,
585 				"missing/invalid port index for port%d\n", i);
586 			fwnode_handle_put(fwnode);
587 			return ERR_PTR(-EINVAL);
588 		}
589 
590 		if (fwnode_property_read_u32(fwnode, "ngpios", &pp->ngpio) &&
591 		    fwnode_property_read_u32(fwnode, "snps,nr-gpios", &pp->ngpio)) {
592 			dev_info(dev,
593 				 "failed to get number of gpios for port%d\n",
594 				 i);
595 			pp->ngpio = DWAPB_MAX_GPIOS;
596 		}
597 
598 		pp->gpio_base	= -1;
599 
600 		/* For internal use only, new platforms mustn't exercise this */
601 		if (is_software_node(fwnode))
602 			fwnode_property_read_u32(fwnode, "gpio-base", &pp->gpio_base);
603 
604 		/*
605 		 * Only port A can provide interrupts in all configurations of
606 		 * the IP.
607 		 */
608 		if (pp->idx == 0)
609 			dwapb_get_irq(dev, fwnode, pp);
610 	}
611 
612 	return pdata;
613 }
614 
615 static void dwapb_assert_reset(void *data)
616 {
617 	struct dwapb_gpio *gpio = data;
618 
619 	reset_control_assert(gpio->rst);
620 }
621 
622 static int dwapb_get_reset(struct dwapb_gpio *gpio)
623 {
624 	int err;
625 
626 	gpio->rst = devm_reset_control_get_optional_shared(gpio->dev, NULL);
627 	if (IS_ERR(gpio->rst))
628 		return dev_err_probe(gpio->dev, PTR_ERR(gpio->rst),
629 				     "Cannot get reset descriptor\n");
630 
631 	err = reset_control_deassert(gpio->rst);
632 	if (err) {
633 		dev_err(gpio->dev, "Cannot deassert reset lane\n");
634 		return err;
635 	}
636 
637 	return devm_add_action_or_reset(gpio->dev, dwapb_assert_reset, gpio);
638 }
639 
640 static void dwapb_disable_clks(void *data)
641 {
642 	struct dwapb_gpio *gpio = data;
643 
644 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
645 }
646 
647 static int dwapb_get_clks(struct dwapb_gpio *gpio)
648 {
649 	int err;
650 
651 	/* Optional bus and debounce clocks */
652 	gpio->clks[0].id = "bus";
653 	gpio->clks[1].id = "db";
654 	err = devm_clk_bulk_get_optional(gpio->dev, DWAPB_NR_CLOCKS,
655 					 gpio->clks);
656 	if (err) {
657 		dev_err(gpio->dev, "Cannot get APB/Debounce clocks\n");
658 		return err;
659 	}
660 
661 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
662 	if (err) {
663 		dev_err(gpio->dev, "Cannot enable APB/Debounce clocks\n");
664 		return err;
665 	}
666 
667 	return devm_add_action_or_reset(gpio->dev, dwapb_disable_clks, gpio);
668 }
669 
670 static const struct of_device_id dwapb_of_match[] = {
671 	{ .compatible = "snps,dw-apb-gpio", .data = (void *)0},
672 	{ .compatible = "apm,xgene-gpio-v2", .data = (void *)GPIO_REG_OFFSET_V2},
673 	{ /* Sentinel */ }
674 };
675 MODULE_DEVICE_TABLE(of, dwapb_of_match);
676 
677 static const struct acpi_device_id dwapb_acpi_match[] = {
678 	{"HISI0181", 0},
679 	{"APMC0D07", 0},
680 	{"APMC0D81", GPIO_REG_OFFSET_V2},
681 	{ }
682 };
683 MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
684 
685 static int dwapb_gpio_probe(struct platform_device *pdev)
686 {
687 	unsigned int i;
688 	struct dwapb_gpio *gpio;
689 	int err;
690 	struct dwapb_platform_data *pdata;
691 	struct device *dev = &pdev->dev;
692 
693 	pdata = dwapb_gpio_get_pdata(dev);
694 	if (IS_ERR(pdata))
695 		return PTR_ERR(pdata);
696 
697 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
698 	if (!gpio)
699 		return -ENOMEM;
700 
701 	gpio->dev = &pdev->dev;
702 	gpio->nr_ports = pdata->nports;
703 
704 	err = dwapb_get_reset(gpio);
705 	if (err)
706 		return err;
707 
708 	gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports,
709 				   sizeof(*gpio->ports), GFP_KERNEL);
710 	if (!gpio->ports)
711 		return -ENOMEM;
712 
713 	gpio->regs = devm_platform_ioremap_resource(pdev, 0);
714 	if (IS_ERR(gpio->regs))
715 		return PTR_ERR(gpio->regs);
716 
717 	err = dwapb_get_clks(gpio);
718 	if (err)
719 		return err;
720 
721 	gpio->flags = (uintptr_t)device_get_match_data(dev);
722 
723 	for (i = 0; i < gpio->nr_ports; i++) {
724 		err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
725 		if (err)
726 			return err;
727 	}
728 
729 	platform_set_drvdata(pdev, gpio);
730 
731 	return 0;
732 }
733 
734 #ifdef CONFIG_PM_SLEEP
735 static int dwapb_gpio_suspend(struct device *dev)
736 {
737 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
738 	struct gpio_chip *gc	= &gpio->ports[0].gc;
739 	unsigned long flags;
740 	int i;
741 
742 	spin_lock_irqsave(&gc->bgpio_lock, flags);
743 	for (i = 0; i < gpio->nr_ports; i++) {
744 		unsigned int offset;
745 		unsigned int idx = gpio->ports[i].idx;
746 		struct dwapb_context *ctx = gpio->ports[i].ctx;
747 
748 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
749 		ctx->dir = dwapb_read(gpio, offset);
750 
751 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
752 		ctx->data = dwapb_read(gpio, offset);
753 
754 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
755 		ctx->ext = dwapb_read(gpio, offset);
756 
757 		/* Only port A can provide interrupts */
758 		if (idx == 0) {
759 			ctx->int_mask	= dwapb_read(gpio, GPIO_INTMASK);
760 			ctx->int_en	= dwapb_read(gpio, GPIO_INTEN);
761 			ctx->int_pol	= dwapb_read(gpio, GPIO_INT_POLARITY);
762 			ctx->int_type	= dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
763 			ctx->int_deb	= dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
764 
765 			/* Mask out interrupts */
766 			dwapb_write(gpio, GPIO_INTMASK, ~ctx->wake_en);
767 		}
768 	}
769 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
770 
771 	clk_bulk_disable_unprepare(DWAPB_NR_CLOCKS, gpio->clks);
772 
773 	return 0;
774 }
775 
776 static int dwapb_gpio_resume(struct device *dev)
777 {
778 	struct dwapb_gpio *gpio = dev_get_drvdata(dev);
779 	struct gpio_chip *gc	= &gpio->ports[0].gc;
780 	unsigned long flags;
781 	int i, err;
782 
783 	err = clk_bulk_prepare_enable(DWAPB_NR_CLOCKS, gpio->clks);
784 	if (err) {
785 		dev_err(gpio->dev, "Cannot reenable APB/Debounce clocks\n");
786 		return err;
787 	}
788 
789 	spin_lock_irqsave(&gc->bgpio_lock, flags);
790 	for (i = 0; i < gpio->nr_ports; i++) {
791 		unsigned int offset;
792 		unsigned int idx = gpio->ports[i].idx;
793 		struct dwapb_context *ctx = gpio->ports[i].ctx;
794 
795 		offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_STRIDE;
796 		dwapb_write(gpio, offset, ctx->data);
797 
798 		offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_STRIDE;
799 		dwapb_write(gpio, offset, ctx->dir);
800 
801 		offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_STRIDE;
802 		dwapb_write(gpio, offset, ctx->ext);
803 
804 		/* Only port A can provide interrupts */
805 		if (idx == 0) {
806 			dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
807 			dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
808 			dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
809 			dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
810 			dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask);
811 
812 			/* Clear out spurious interrupts */
813 			dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
814 		}
815 	}
816 	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
817 
818 	return 0;
819 }
820 #endif
821 
822 static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
823 			 dwapb_gpio_resume);
824 
825 static struct platform_driver dwapb_gpio_driver = {
826 	.driver		= {
827 		.name	= DWAPB_DRIVER_NAME,
828 		.pm	= &dwapb_gpio_pm_ops,
829 		.of_match_table = dwapb_of_match,
830 		.acpi_match_table = dwapb_acpi_match,
831 	},
832 	.probe		= dwapb_gpio_probe,
833 };
834 
835 module_platform_driver(dwapb_gpio_driver);
836 
837 MODULE_LICENSE("GPL");
838 MODULE_AUTHOR("Jamie Iles");
839 MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
840 MODULE_ALIAS("platform:" DWAPB_DRIVER_NAME);
841