xref: /openbmc/linux/drivers/gpio/gpio-davinci.c (revision 603c09f2)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * TI DaVinci GPIO Support
4  *
5  * Copyright (c) 2006-2007 David Brownell
6  * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
7  */
8 
9 #include <linux/gpio/driver.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/clk.h>
13 #include <linux/err.h>
14 #include <linux/io.h>
15 #include <linux/irq.h>
16 #include <linux/irqdomain.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_device.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/platform_device.h>
22 #include <linux/platform_data/gpio-davinci.h>
23 #include <linux/irqchip/chained_irq.h>
24 #include <linux/spinlock.h>
25 #include <linux/pm_runtime.h>
26 
27 #include <asm-generic/gpio.h>
28 
29 #define MAX_REGS_BANKS 5
30 #define MAX_INT_PER_BANK 32
31 
32 struct davinci_gpio_regs {
33 	u32	dir;
34 	u32	out_data;
35 	u32	set_data;
36 	u32	clr_data;
37 	u32	in_data;
38 	u32	set_rising;
39 	u32	clr_rising;
40 	u32	set_falling;
41 	u32	clr_falling;
42 	u32	intstat;
43 };
44 
45 typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
46 
47 #define BINTEN	0x8 /* GPIO Interrupt Per-Bank Enable Register */
48 
49 static void __iomem *gpio_base;
50 static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
51 
52 struct davinci_gpio_irq_data {
53 	void __iomem			*regs;
54 	struct davinci_gpio_controller	*chip;
55 	int				bank_num;
56 };
57 
58 struct davinci_gpio_controller {
59 	struct gpio_chip	chip;
60 	struct irq_domain	*irq_domain;
61 	/* Serialize access to GPIO registers */
62 	spinlock_t		lock;
63 	void __iomem		*regs[MAX_REGS_BANKS];
64 	int			gpio_unbanked;
65 	int			irqs[MAX_INT_PER_BANK];
66 	struct davinci_gpio_regs context[MAX_REGS_BANKS];
67 	u32			binten_context;
68 };
69 
70 static inline u32 __gpio_mask(unsigned gpio)
71 {
72 	return 1 << (gpio % 32);
73 }
74 
75 static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d)
76 {
77 	struct davinci_gpio_regs __iomem *g;
78 
79 	g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d);
80 
81 	return g;
82 }
83 
84 static int davinci_gpio_irq_setup(struct platform_device *pdev);
85 
86 /*--------------------------------------------------------------------------*/
87 
88 /* board setup code *MUST* setup pinmux and enable the GPIO clock. */
89 static inline int __davinci_direction(struct gpio_chip *chip,
90 			unsigned offset, bool out, int value)
91 {
92 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
93 	struct davinci_gpio_regs __iomem *g;
94 	unsigned long flags;
95 	u32 temp;
96 	int bank = offset / 32;
97 	u32 mask = __gpio_mask(offset);
98 
99 	g = d->regs[bank];
100 	spin_lock_irqsave(&d->lock, flags);
101 	temp = readl_relaxed(&g->dir);
102 	if (out) {
103 		temp &= ~mask;
104 		writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
105 	} else {
106 		temp |= mask;
107 	}
108 	writel_relaxed(temp, &g->dir);
109 	spin_unlock_irqrestore(&d->lock, flags);
110 
111 	return 0;
112 }
113 
114 static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
115 {
116 	return __davinci_direction(chip, offset, false, 0);
117 }
118 
119 static int
120 davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
121 {
122 	return __davinci_direction(chip, offset, true, value);
123 }
124 
125 /*
126  * Read the pin's value (works even if it's set up as output);
127  * returns zero/nonzero.
128  *
129  * Note that changes are synched to the GPIO clock, so reading values back
130  * right after you've set them may give old values.
131  */
132 static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
133 {
134 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
135 	struct davinci_gpio_regs __iomem *g;
136 	int bank = offset / 32;
137 
138 	g = d->regs[bank];
139 
140 	return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
141 }
142 
143 /*
144  * Assuming the pin is muxed as a gpio output, set its output value.
145  */
146 static void
147 davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
148 {
149 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
150 	struct davinci_gpio_regs __iomem *g;
151 	int bank = offset / 32;
152 
153 	g = d->regs[bank];
154 
155 	writel_relaxed(__gpio_mask(offset),
156 		       value ? &g->set_data : &g->clr_data);
157 }
158 
159 static struct davinci_gpio_platform_data *
160 davinci_gpio_get_pdata(struct platform_device *pdev)
161 {
162 	struct device_node *dn = pdev->dev.of_node;
163 	struct davinci_gpio_platform_data *pdata;
164 	int ret;
165 	u32 val;
166 
167 	if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
168 		return dev_get_platdata(&pdev->dev);
169 
170 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
171 	if (!pdata)
172 		return NULL;
173 
174 	ret = of_property_read_u32(dn, "ti,ngpio", &val);
175 	if (ret)
176 		goto of_err;
177 
178 	pdata->ngpio = val;
179 
180 	ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val);
181 	if (ret)
182 		goto of_err;
183 
184 	pdata->gpio_unbanked = val;
185 
186 	return pdata;
187 
188 of_err:
189 	dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret);
190 	return NULL;
191 }
192 
193 static int davinci_gpio_probe(struct platform_device *pdev)
194 {
195 	int bank, i, ret = 0;
196 	unsigned int ngpio, nbank, nirq;
197 	struct davinci_gpio_controller *chips;
198 	struct davinci_gpio_platform_data *pdata;
199 	struct device *dev = &pdev->dev;
200 
201 	pdata = davinci_gpio_get_pdata(pdev);
202 	if (!pdata) {
203 		dev_err(dev, "No platform data found\n");
204 		return -EINVAL;
205 	}
206 
207 	dev->platform_data = pdata;
208 
209 	/*
210 	 * The gpio banks conceptually expose a segmented bitmap,
211 	 * and "ngpio" is one more than the largest zero-based
212 	 * bit index that's valid.
213 	 */
214 	ngpio = pdata->ngpio;
215 	if (ngpio == 0) {
216 		dev_err(dev, "How many GPIOs?\n");
217 		return -EINVAL;
218 	}
219 
220 	if (WARN_ON(ARCH_NR_GPIOS < ngpio))
221 		ngpio = ARCH_NR_GPIOS;
222 
223 	/*
224 	 * If there are unbanked interrupts then the number of
225 	 * interrupts is equal to number of gpios else all are banked so
226 	 * number of interrupts is equal to number of banks(each with 16 gpios)
227 	 */
228 	if (pdata->gpio_unbanked)
229 		nirq = pdata->gpio_unbanked;
230 	else
231 		nirq = DIV_ROUND_UP(ngpio, 16);
232 
233 	chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL);
234 	if (!chips)
235 		return -ENOMEM;
236 
237 	gpio_base = devm_platform_ioremap_resource(pdev, 0);
238 	if (IS_ERR(gpio_base))
239 		return PTR_ERR(gpio_base);
240 
241 	for (i = 0; i < nirq; i++) {
242 		chips->irqs[i] = platform_get_irq(pdev, i);
243 		if (chips->irqs[i] < 0)
244 			return dev_err_probe(dev, chips->irqs[i], "IRQ not populated\n");
245 	}
246 
247 	chips->chip.label = dev_name(dev);
248 
249 	chips->chip.direction_input = davinci_direction_in;
250 	chips->chip.get = davinci_gpio_get;
251 	chips->chip.direction_output = davinci_direction_out;
252 	chips->chip.set = davinci_gpio_set;
253 
254 	chips->chip.ngpio = ngpio;
255 	chips->chip.base = pdata->no_auto_base ? pdata->base : -1;
256 
257 #ifdef CONFIG_OF_GPIO
258 	chips->chip.of_gpio_n_cells = 2;
259 	chips->chip.parent = dev;
260 	chips->chip.request = gpiochip_generic_request;
261 	chips->chip.free = gpiochip_generic_free;
262 #endif
263 	spin_lock_init(&chips->lock);
264 
265 	nbank = DIV_ROUND_UP(ngpio, 32);
266 	for (bank = 0; bank < nbank; bank++)
267 		chips->regs[bank] = gpio_base + offset_array[bank];
268 
269 	ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
270 	if (ret)
271 		return ret;
272 
273 	platform_set_drvdata(pdev, chips);
274 	ret = davinci_gpio_irq_setup(pdev);
275 	if (ret)
276 		return ret;
277 
278 	return 0;
279 }
280 
281 /*--------------------------------------------------------------------------*/
282 /*
283  * We expect irqs will normally be set up as input pins, but they can also be
284  * used as output pins ... which is convenient for testing.
285  *
286  * NOTE:  The first few GPIOs also have direct INTC hookups in addition
287  * to their GPIOBNK0 irq, with a bit less overhead.
288  *
289  * All those INTC hookups (direct, plus several IRQ banks) can also
290  * serve as EDMA event triggers.
291  */
292 
293 static void gpio_irq_disable(struct irq_data *d)
294 {
295 	struct davinci_gpio_regs __iomem *g = irq2regs(d);
296 	uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
297 
298 	writel_relaxed(mask, &g->clr_falling);
299 	writel_relaxed(mask, &g->clr_rising);
300 }
301 
302 static void gpio_irq_enable(struct irq_data *d)
303 {
304 	struct davinci_gpio_regs __iomem *g = irq2regs(d);
305 	uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
306 	unsigned status = irqd_get_trigger_type(d);
307 
308 	status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
309 	if (!status)
310 		status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
311 
312 	if (status & IRQ_TYPE_EDGE_FALLING)
313 		writel_relaxed(mask, &g->set_falling);
314 	if (status & IRQ_TYPE_EDGE_RISING)
315 		writel_relaxed(mask, &g->set_rising);
316 }
317 
318 static int gpio_irq_type(struct irq_data *d, unsigned trigger)
319 {
320 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
321 		return -EINVAL;
322 
323 	return 0;
324 }
325 
326 static struct irq_chip gpio_irqchip = {
327 	.name		= "GPIO",
328 	.irq_enable	= gpio_irq_enable,
329 	.irq_disable	= gpio_irq_disable,
330 	.irq_set_type	= gpio_irq_type,
331 	.flags		= IRQCHIP_SET_TYPE_MASKED,
332 };
333 
334 static void gpio_irq_handler(struct irq_desc *desc)
335 {
336 	struct davinci_gpio_regs __iomem *g;
337 	u32 mask = 0xffff;
338 	int bank_num;
339 	struct davinci_gpio_controller *d;
340 	struct davinci_gpio_irq_data *irqdata;
341 
342 	irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
343 	bank_num = irqdata->bank_num;
344 	g = irqdata->regs;
345 	d = irqdata->chip;
346 
347 	/* we only care about one bank */
348 	if ((bank_num % 2) == 1)
349 		mask <<= 16;
350 
351 	/* temporarily mask (level sensitive) parent IRQ */
352 	chained_irq_enter(irq_desc_get_chip(desc), desc);
353 	while (1) {
354 		u32		status;
355 		int		bit;
356 		irq_hw_number_t hw_irq;
357 
358 		/* ack any irqs */
359 		status = readl_relaxed(&g->intstat) & mask;
360 		if (!status)
361 			break;
362 		writel_relaxed(status, &g->intstat);
363 
364 		/* now demux them to the right lowlevel handler */
365 
366 		while (status) {
367 			bit = __ffs(status);
368 			status &= ~BIT(bit);
369 			/* Max number of gpios per controller is 144 so
370 			 * hw_irq will be in [0..143]
371 			 */
372 			hw_irq = (bank_num / 2) * 32 + bit;
373 
374 			generic_handle_domain_irq(d->irq_domain, hw_irq);
375 		}
376 	}
377 	chained_irq_exit(irq_desc_get_chip(desc), desc);
378 	/* now it may re-trigger */
379 }
380 
381 static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
382 {
383 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
384 
385 	if (d->irq_domain)
386 		return irq_create_mapping(d->irq_domain, offset);
387 	else
388 		return -ENXIO;
389 }
390 
391 static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
392 {
393 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
394 
395 	/*
396 	 * NOTE:  we assume for now that only irqs in the first gpio_chip
397 	 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
398 	 */
399 	if (offset < d->gpio_unbanked)
400 		return d->irqs[offset];
401 	else
402 		return -ENODEV;
403 }
404 
405 static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
406 {
407 	struct davinci_gpio_controller *d;
408 	struct davinci_gpio_regs __iomem *g;
409 	u32 mask, i;
410 
411 	d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
412 	g = (struct davinci_gpio_regs __iomem *)d->regs[0];
413 	for (i = 0; i < MAX_INT_PER_BANK; i++)
414 		if (data->irq == d->irqs[i])
415 			break;
416 
417 	if (i == MAX_INT_PER_BANK)
418 		return -EINVAL;
419 
420 	mask = __gpio_mask(i);
421 
422 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
423 		return -EINVAL;
424 
425 	writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
426 		     ? &g->set_falling : &g->clr_falling);
427 	writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
428 		     ? &g->set_rising : &g->clr_rising);
429 
430 	return 0;
431 }
432 
433 static int
434 davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
435 		     irq_hw_number_t hw)
436 {
437 	struct davinci_gpio_controller *chips =
438 				(struct davinci_gpio_controller *)d->host_data;
439 	struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32];
440 
441 	irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
442 				"davinci_gpio");
443 	irq_set_irq_type(irq, IRQ_TYPE_NONE);
444 	irq_set_chip_data(irq, (__force void *)g);
445 	irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw));
446 
447 	return 0;
448 }
449 
450 static const struct irq_domain_ops davinci_gpio_irq_ops = {
451 	.map = davinci_gpio_irq_map,
452 	.xlate = irq_domain_xlate_onetwocell,
453 };
454 
455 static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
456 {
457 	static struct irq_chip_type gpio_unbanked;
458 
459 	gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
460 
461 	return &gpio_unbanked.chip;
462 };
463 
464 static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
465 {
466 	static struct irq_chip gpio_unbanked;
467 
468 	gpio_unbanked = *irq_get_chip(irq);
469 	return &gpio_unbanked;
470 };
471 
472 static const struct of_device_id davinci_gpio_ids[];
473 
474 /*
475  * NOTE:  for suspend/resume, probably best to make a platform_device with
476  * suspend_late/resume_resume calls hooking into results of the set_wake()
477  * calls ... so if no gpios are wakeup events the clock can be disabled,
478  * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
479  * (dm6446) can be set appropriately for GPIOV33 pins.
480  */
481 
482 static int davinci_gpio_irq_setup(struct platform_device *pdev)
483 {
484 	unsigned	gpio, bank;
485 	int		irq;
486 	int		ret;
487 	struct clk	*clk;
488 	u32		binten = 0;
489 	unsigned	ngpio;
490 	struct device *dev = &pdev->dev;
491 	struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
492 	struct davinci_gpio_platform_data *pdata = dev->platform_data;
493 	struct davinci_gpio_regs __iomem *g;
494 	struct irq_domain	*irq_domain = NULL;
495 	const struct of_device_id *match;
496 	struct irq_chip *irq_chip;
497 	struct davinci_gpio_irq_data *irqdata;
498 	gpio_get_irq_chip_cb_t gpio_get_irq_chip;
499 
500 	/*
501 	 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
502 	 */
503 	gpio_get_irq_chip = davinci_gpio_get_irq_chip;
504 	match = of_match_device(of_match_ptr(davinci_gpio_ids),
505 				dev);
506 	if (match)
507 		gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)match->data;
508 
509 	ngpio = pdata->ngpio;
510 
511 	clk = devm_clk_get(dev, "gpio");
512 	if (IS_ERR(clk)) {
513 		dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk));
514 		return PTR_ERR(clk);
515 	}
516 
517 	ret = clk_prepare_enable(clk);
518 	if (ret)
519 		return ret;
520 
521 	if (!pdata->gpio_unbanked) {
522 		irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0);
523 		if (irq < 0) {
524 			dev_err(dev, "Couldn't allocate IRQ numbers\n");
525 			clk_disable_unprepare(clk);
526 			return irq;
527 		}
528 
529 		irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0,
530 							&davinci_gpio_irq_ops,
531 							chips);
532 		if (!irq_domain) {
533 			dev_err(dev, "Couldn't register an IRQ domain\n");
534 			clk_disable_unprepare(clk);
535 			return -ENODEV;
536 		}
537 	}
538 
539 	/*
540 	 * Arrange gpio_to_irq() support, handling either direct IRQs or
541 	 * banked IRQs.  Having GPIOs in the first GPIO bank use direct
542 	 * IRQs, while the others use banked IRQs, would need some setup
543 	 * tweaks to recognize hardware which can do that.
544 	 */
545 	chips->chip.to_irq = gpio_to_irq_banked;
546 	chips->irq_domain = irq_domain;
547 
548 	/*
549 	 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
550 	 * controller only handling trigger modes.  We currently assume no
551 	 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
552 	 */
553 	if (pdata->gpio_unbanked) {
554 		/* pass "bank 0" GPIO IRQs to AINTC */
555 		chips->chip.to_irq = gpio_to_irq_unbanked;
556 		chips->gpio_unbanked = pdata->gpio_unbanked;
557 		binten = GENMASK(pdata->gpio_unbanked / 16, 0);
558 
559 		/* AINTC handles mask/unmask; GPIO handles triggering */
560 		irq = chips->irqs[0];
561 		irq_chip = gpio_get_irq_chip(irq);
562 		irq_chip->name = "GPIO-AINTC";
563 		irq_chip->irq_set_type = gpio_irq_type_unbanked;
564 
565 		/* default trigger: both edges */
566 		g = chips->regs[0];
567 		writel_relaxed(~0, &g->set_falling);
568 		writel_relaxed(~0, &g->set_rising);
569 
570 		/* set the direct IRQs up to use that irqchip */
571 		for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++) {
572 			irq_set_chip(chips->irqs[gpio], irq_chip);
573 			irq_set_handler_data(chips->irqs[gpio], chips);
574 			irq_set_status_flags(chips->irqs[gpio],
575 					     IRQ_TYPE_EDGE_BOTH);
576 		}
577 
578 		goto done;
579 	}
580 
581 	/*
582 	 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
583 	 * then chain through our own handler.
584 	 */
585 	for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) {
586 		/* disabled by default, enabled only as needed
587 		 * There are register sets for 32 GPIOs. 2 banks of 16
588 		 * GPIOs are covered by each set of registers hence divide by 2
589 		 */
590 		g = chips->regs[bank / 2];
591 		writel_relaxed(~0, &g->clr_falling);
592 		writel_relaxed(~0, &g->clr_rising);
593 
594 		/*
595 		 * Each chip handles 32 gpios, and each irq bank consists of 16
596 		 * gpio irqs. Pass the irq bank's corresponding controller to
597 		 * the chained irq handler.
598 		 */
599 		irqdata = devm_kzalloc(&pdev->dev,
600 				       sizeof(struct
601 					      davinci_gpio_irq_data),
602 					      GFP_KERNEL);
603 		if (!irqdata) {
604 			clk_disable_unprepare(clk);
605 			return -ENOMEM;
606 		}
607 
608 		irqdata->regs = g;
609 		irqdata->bank_num = bank;
610 		irqdata->chip = chips;
611 
612 		irq_set_chained_handler_and_data(chips->irqs[bank],
613 						 gpio_irq_handler, irqdata);
614 
615 		binten |= BIT(bank);
616 	}
617 
618 done:
619 	/*
620 	 * BINTEN -- per-bank interrupt enable. genirq would also let these
621 	 * bits be set/cleared dynamically.
622 	 */
623 	writel_relaxed(binten, gpio_base + BINTEN);
624 
625 	return 0;
626 }
627 
628 static void davinci_gpio_save_context(struct davinci_gpio_controller *chips,
629 				      u32 nbank)
630 {
631 	struct davinci_gpio_regs __iomem *g;
632 	struct davinci_gpio_regs *context;
633 	u32 bank;
634 	void __iomem *base;
635 
636 	base = chips->regs[0] - offset_array[0];
637 	chips->binten_context = readl_relaxed(base + BINTEN);
638 
639 	for (bank = 0; bank < nbank; bank++) {
640 		g = chips->regs[bank];
641 		context = &chips->context[bank];
642 		context->dir = readl_relaxed(&g->dir);
643 		context->set_data = readl_relaxed(&g->set_data);
644 		context->set_rising = readl_relaxed(&g->set_rising);
645 		context->set_falling = readl_relaxed(&g->set_falling);
646 	}
647 
648 	/* Clear Bank interrupt enable bit */
649 	writel_relaxed(0, base + BINTEN);
650 
651 	/* Clear all interrupt status registers */
652 	writel_relaxed(GENMASK(31, 0), &g->intstat);
653 }
654 
655 static void davinci_gpio_restore_context(struct davinci_gpio_controller *chips,
656 					 u32 nbank)
657 {
658 	struct davinci_gpio_regs __iomem *g;
659 	struct davinci_gpio_regs *context;
660 	u32 bank;
661 	void __iomem *base;
662 
663 	base = chips->regs[0] - offset_array[0];
664 
665 	if (readl_relaxed(base + BINTEN) != chips->binten_context)
666 		writel_relaxed(chips->binten_context, base + BINTEN);
667 
668 	for (bank = 0; bank < nbank; bank++) {
669 		g = chips->regs[bank];
670 		context = &chips->context[bank];
671 		if (readl_relaxed(&g->dir) != context->dir)
672 			writel_relaxed(context->dir, &g->dir);
673 		if (readl_relaxed(&g->set_data) != context->set_data)
674 			writel_relaxed(context->set_data, &g->set_data);
675 		if (readl_relaxed(&g->set_rising) != context->set_rising)
676 			writel_relaxed(context->set_rising, &g->set_rising);
677 		if (readl_relaxed(&g->set_falling) != context->set_falling)
678 			writel_relaxed(context->set_falling, &g->set_falling);
679 	}
680 }
681 
682 static int davinci_gpio_suspend(struct device *dev)
683 {
684 	struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
685 	struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev);
686 	u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32);
687 
688 	davinci_gpio_save_context(chips, nbank);
689 
690 	return 0;
691 }
692 
693 static int davinci_gpio_resume(struct device *dev)
694 {
695 	struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
696 	struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev);
697 	u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32);
698 
699 	davinci_gpio_restore_context(chips, nbank);
700 
701 	return 0;
702 }
703 
704 DEFINE_SIMPLE_DEV_PM_OPS(davinci_gpio_dev_pm_ops, davinci_gpio_suspend,
705 			 davinci_gpio_resume);
706 
707 static const struct of_device_id davinci_gpio_ids[] = {
708 	{ .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
709 	{ .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip},
710 	{ .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
711 	{ /* sentinel */ },
712 };
713 MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
714 
715 static struct platform_driver davinci_gpio_driver = {
716 	.probe		= davinci_gpio_probe,
717 	.driver		= {
718 		.name		= "davinci_gpio",
719 		.pm = pm_sleep_ptr(&davinci_gpio_dev_pm_ops),
720 		.of_match_table	= of_match_ptr(davinci_gpio_ids),
721 	},
722 };
723 
724 /**
725  * GPIO driver registration needs to be done before machine_init functions
726  * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
727  */
728 static int __init davinci_gpio_drv_reg(void)
729 {
730 	return platform_driver_register(&davinci_gpio_driver);
731 }
732 postcore_initcall(davinci_gpio_drv_reg);
733