xref: /linux/drivers/gpio/gpio-davinci.c (revision c2a44a02d785b5dc06d68060079e2daf67a67e5a)
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/cleanup.h>
10 #include <linux/gpio/driver.h>
11 #include <linux/errno.h>
12 #include <linux/kernel.h>
13 #include <linux/clk.h>
14 #include <linux/err.h>
15 #include <linux/io.h>
16 #include <linux/irq.h>
17 #include <linux/irqdomain.h>
18 #include <linux/module.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/platform_device.h>
21 #include <linux/property.h>
22 #include <linux/irqchip/chained_irq.h>
23 #include <linux/spinlock.h>
24 #include <linux/pm_runtime.h>
25 
26 #define MAX_REGS_BANKS 5
27 #define MAX_INT_PER_BANK 32
28 
29 struct davinci_gpio_regs {
30 	u32	dir;
31 	u32	out_data;
32 	u32	set_data;
33 	u32	clr_data;
34 	u32	in_data;
35 	u32	set_rising;
36 	u32	clr_rising;
37 	u32	set_falling;
38 	u32	clr_falling;
39 	u32	intstat;
40 };
41 
42 typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
43 
44 #define BINTEN	0x8 /* GPIO Interrupt Per-Bank Enable Register */
45 
46 static void __iomem *gpio_base;
47 static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
48 
49 struct davinci_gpio_irq_data {
50 	void __iomem			*regs;
51 	struct davinci_gpio_controller	*chip;
52 	int				bank_num;
53 };
54 
55 struct davinci_gpio_controller {
56 	struct gpio_chip	chip;
57 	struct irq_domain	*irq_domain;
58 	/* Serialize access to GPIO registers */
59 	spinlock_t		lock;
60 	void __iomem		*regs[MAX_REGS_BANKS];
61 	int			gpio_unbanked;
62 	int			irqs[MAX_INT_PER_BANK];
63 	struct davinci_gpio_regs context[MAX_REGS_BANKS];
64 	u32			binten_context;
65 };
66 
__gpio_mask(unsigned gpio)67 static inline u32 __gpio_mask(unsigned gpio)
68 {
69 	return 1 << (gpio % 32);
70 }
71 
72 static int davinci_gpio_irq_setup(struct platform_device *pdev);
73 
74 /*--------------------------------------------------------------------------*/
75 
76 /* board setup code *MUST* setup pinmux and enable the GPIO clock. */
__davinci_direction(struct gpio_chip * chip,unsigned offset,bool out,int value)77 static inline int __davinci_direction(struct gpio_chip *chip,
78 			unsigned offset, bool out, int value)
79 {
80 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
81 	struct davinci_gpio_regs __iomem *g;
82 	unsigned long flags;
83 	u32 temp;
84 	int bank = offset / 32;
85 	u32 mask = __gpio_mask(offset);
86 
87 	g = d->regs[bank];
88 	spin_lock_irqsave(&d->lock, flags);
89 	temp = readl_relaxed(&g->dir);
90 	if (out) {
91 		temp &= ~mask;
92 		writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
93 	} else {
94 		temp |= mask;
95 	}
96 	writel_relaxed(temp, &g->dir);
97 	spin_unlock_irqrestore(&d->lock, flags);
98 
99 	return 0;
100 }
101 
davinci_direction_in(struct gpio_chip * chip,unsigned offset)102 static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
103 {
104 	return __davinci_direction(chip, offset, false, 0);
105 }
106 
107 static int
davinci_direction_out(struct gpio_chip * chip,unsigned offset,int value)108 davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
109 {
110 	return __davinci_direction(chip, offset, true, value);
111 }
112 
davinci_get_direction(struct gpio_chip * chip,unsigned int offset)113 static int davinci_get_direction(struct gpio_chip *chip, unsigned int offset)
114 {
115 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
116 	struct davinci_gpio_regs __iomem *g;
117 	u32 mask = __gpio_mask(offset), val;
118 	int bank = offset / 32;
119 
120 	g = d->regs[bank];
121 
122 	guard(spinlock_irqsave)(&d->lock);
123 
124 	val = readl_relaxed(&g->dir);
125 
126 	return (val & mask) ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
127 }
128 
129 /*
130  * Read the pin's value (works even if it's set up as output);
131  * returns zero/nonzero.
132  *
133  * Note that changes are synched to the GPIO clock, so reading values back
134  * right after you've set them may give old values.
135  */
davinci_gpio_get(struct gpio_chip * chip,unsigned offset)136 static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
137 {
138 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
139 	struct davinci_gpio_regs __iomem *g;
140 	int bank = offset / 32;
141 
142 	g = d->regs[bank];
143 
144 	return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
145 }
146 
147 /*
148  * Assuming the pin is muxed as a gpio output, set its output value.
149  */
150 static int
davinci_gpio_set(struct gpio_chip * chip,unsigned offset,int value)151 davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
152 {
153 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
154 	struct davinci_gpio_regs __iomem *g;
155 	int bank = offset / 32;
156 
157 	g = d->regs[bank];
158 
159 	writel_relaxed(__gpio_mask(offset),
160 		       value ? &g->set_data : &g->clr_data);
161 
162 	return 0;
163 }
164 
davinci_gpio_probe(struct platform_device * pdev)165 static int davinci_gpio_probe(struct platform_device *pdev)
166 {
167 	int bank, i, ret = 0;
168 	unsigned int ngpio, nbank, nirq, gpio_unbanked;
169 	struct davinci_gpio_controller *chips;
170 	struct device *dev = &pdev->dev;
171 
172 	/*
173 	 * The gpio banks conceptually expose a segmented bitmap,
174 	 * and "ngpio" is one more than the largest zero-based
175 	 * bit index that's valid.
176 	 */
177 	ret = device_property_read_u32(dev, "ti,ngpio", &ngpio);
178 	if (ret)
179 		return dev_err_probe(dev, ret, "Failed to get the number of GPIOs\n");
180 	if (ngpio == 0)
181 		return dev_err_probe(dev, -EINVAL, "How many GPIOs?\n");
182 
183 	/*
184 	 * If there are unbanked interrupts then the number of
185 	 * interrupts is equal to number of gpios else all are banked so
186 	 * number of interrupts is equal to number of banks(each with 16 gpios)
187 	 */
188 	ret = device_property_read_u32(dev, "ti,davinci-gpio-unbanked",
189 				       &gpio_unbanked);
190 	if (ret)
191 		return dev_err_probe(dev, ret, "Failed to get the unbanked GPIOs property\n");
192 
193 	if (gpio_unbanked)
194 		nirq = gpio_unbanked;
195 	else
196 		nirq = DIV_ROUND_UP(ngpio, 16);
197 
198 	if (nirq > MAX_INT_PER_BANK) {
199 		dev_err(dev, "Too many IRQs!\n");
200 		return -EINVAL;
201 	}
202 
203 	chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL);
204 	if (!chips)
205 		return -ENOMEM;
206 
207 	gpio_base = devm_platform_ioremap_resource(pdev, 0);
208 	if (IS_ERR(gpio_base))
209 		return PTR_ERR(gpio_base);
210 
211 	for (i = 0; i < nirq; i++) {
212 		chips->irqs[i] = platform_get_irq(pdev, i);
213 		if (chips->irqs[i] < 0)
214 			return chips->irqs[i];
215 	}
216 
217 	chips->chip.label = dev_name(dev);
218 
219 	chips->chip.direction_input = davinci_direction_in;
220 	chips->chip.get = davinci_gpio_get;
221 	chips->chip.direction_output = davinci_direction_out;
222 	chips->chip.set = davinci_gpio_set;
223 	chips->chip.get_direction = davinci_get_direction;
224 
225 	chips->chip.ngpio = ngpio;
226 	chips->chip.base = -1;
227 
228 #ifdef CONFIG_OF_GPIO
229 	chips->chip.parent = dev;
230 	chips->chip.request = gpiochip_generic_request;
231 	chips->chip.free = gpiochip_generic_free;
232 #endif
233 	spin_lock_init(&chips->lock);
234 
235 	chips->gpio_unbanked = gpio_unbanked;
236 
237 	nbank = DIV_ROUND_UP(ngpio, 32);
238 	for (bank = 0; bank < nbank; bank++)
239 		chips->regs[bank] = gpio_base + offset_array[bank];
240 
241 	ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
242 	if (ret)
243 		return ret;
244 
245 	platform_set_drvdata(pdev, chips);
246 	ret = davinci_gpio_irq_setup(pdev);
247 	if (ret)
248 		return ret;
249 
250 	return 0;
251 }
252 
253 /*--------------------------------------------------------------------------*/
254 /*
255  * We expect irqs will normally be set up as input pins, but they can also be
256  * used as output pins ... which is convenient for testing.
257  *
258  * NOTE:  The first few GPIOs also have direct INTC hookups in addition
259  * to their GPIOBNK0 irq, with a bit less overhead.
260  *
261  * All those INTC hookups (direct, plus several IRQ banks) can also
262  * serve as EDMA event triggers.
263  */
264 
gpio_irq_mask(struct irq_data * d)265 static void gpio_irq_mask(struct irq_data *d)
266 {
267 	struct davinci_gpio_controller *chips = irq_data_get_irq_chip_data(d);
268 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
269 	struct davinci_gpio_regs __iomem *g = chips->regs[hwirq / 32];
270 	uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
271 
272 	writel_relaxed(mask, &g->clr_falling);
273 	writel_relaxed(mask, &g->clr_rising);
274 
275 	gpiochip_disable_irq(&chips->chip, hwirq);
276 }
277 
gpio_irq_unmask(struct irq_data * d)278 static void gpio_irq_unmask(struct irq_data *d)
279 {
280 	struct davinci_gpio_controller *chips = irq_data_get_irq_chip_data(d);
281 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
282 	struct davinci_gpio_regs __iomem *g = chips->regs[hwirq / 32];
283 	uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
284 	unsigned status = irqd_get_trigger_type(d);
285 
286 	gpiochip_enable_irq(&chips->chip, hwirq);
287 
288 	status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
289 	if (!status)
290 		status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
291 
292 	if (status & IRQ_TYPE_EDGE_FALLING)
293 		writel_relaxed(mask, &g->set_falling);
294 	if (status & IRQ_TYPE_EDGE_RISING)
295 		writel_relaxed(mask, &g->set_rising);
296 }
297 
gpio_irq_type(struct irq_data * d,unsigned trigger)298 static int gpio_irq_type(struct irq_data *d, unsigned trigger)
299 {
300 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
301 		return -EINVAL;
302 
303 	return 0;
304 }
305 
306 static const struct irq_chip gpio_irqchip = {
307 	.name		= "GPIO",
308 	.irq_unmask	= gpio_irq_unmask,
309 	.irq_mask	= gpio_irq_mask,
310 	.irq_set_type	= gpio_irq_type,
311 	.flags		= IRQCHIP_IMMUTABLE | IRQCHIP_SET_TYPE_MASKED | IRQCHIP_SKIP_SET_WAKE,
312 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
313 };
314 
gpio_irq_handler(struct irq_desc * desc)315 static void gpio_irq_handler(struct irq_desc *desc)
316 {
317 	struct davinci_gpio_regs __iomem *g;
318 	u32 mask = 0xffff;
319 	int bank_num;
320 	struct davinci_gpio_controller *d;
321 	struct davinci_gpio_irq_data *irqdata;
322 
323 	irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
324 	bank_num = irqdata->bank_num;
325 	g = irqdata->regs;
326 	d = irqdata->chip;
327 
328 	/* we only care about one bank */
329 	if ((bank_num % 2) == 1)
330 		mask <<= 16;
331 
332 	/* temporarily mask (level sensitive) parent IRQ */
333 	chained_irq_enter(irq_desc_get_chip(desc), desc);
334 	while (1) {
335 		u32		status;
336 		int		bit;
337 		irq_hw_number_t hw_irq;
338 
339 		/* ack any irqs */
340 		status = readl_relaxed(&g->intstat) & mask;
341 		if (!status)
342 			break;
343 		writel_relaxed(status, &g->intstat);
344 
345 		/* now demux them to the right lowlevel handler */
346 
347 		while (status) {
348 			bit = __ffs(status);
349 			status &= ~BIT(bit);
350 			/* Max number of gpios per controller is 144 so
351 			 * hw_irq will be in [0..143]
352 			 */
353 			hw_irq = (bank_num / 2) * 32 + bit;
354 
355 			generic_handle_domain_irq(d->irq_domain, hw_irq);
356 		}
357 	}
358 	chained_irq_exit(irq_desc_get_chip(desc), desc);
359 	/* now it may re-trigger */
360 }
361 
gpio_to_irq_banked(struct gpio_chip * chip,unsigned offset)362 static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
363 {
364 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
365 
366 	if (d->irq_domain)
367 		return irq_create_mapping(d->irq_domain, offset);
368 	else
369 		return -ENXIO;
370 }
371 
gpio_to_irq_unbanked(struct gpio_chip * chip,unsigned offset)372 static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
373 {
374 	struct davinci_gpio_controller *d = gpiochip_get_data(chip);
375 
376 	/*
377 	 * NOTE:  we assume for now that only irqs in the first gpio_chip
378 	 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
379 	 */
380 	if (offset < d->gpio_unbanked)
381 		return d->irqs[offset];
382 	else
383 		return -ENODEV;
384 }
385 
gpio_irq_type_unbanked(struct irq_data * data,unsigned trigger)386 static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
387 {
388 	struct davinci_gpio_controller *d;
389 	struct davinci_gpio_regs __iomem *g;
390 	u32 mask, i;
391 
392 	d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
393 	g = (struct davinci_gpio_regs __iomem *)d->regs[0];
394 	for (i = 0; i < MAX_INT_PER_BANK; i++)
395 		if (data->irq == d->irqs[i])
396 			break;
397 
398 	if (i == MAX_INT_PER_BANK)
399 		return -EINVAL;
400 
401 	mask = __gpio_mask(i);
402 
403 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
404 		return -EINVAL;
405 
406 	writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
407 		     ? &g->set_falling : &g->clr_falling);
408 	writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
409 		     ? &g->set_rising : &g->clr_rising);
410 
411 	return 0;
412 }
413 
414 static int
davinci_gpio_irq_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hw)415 davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
416 		     irq_hw_number_t hw)
417 {
418 	struct davinci_gpio_controller *chips =
419 				(struct davinci_gpio_controller *)d->host_data;
420 
421 	irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
422 				"davinci_gpio");
423 	irq_set_irq_type(irq, IRQ_TYPE_NONE);
424 	irq_set_chip_data(irq, (__force void *)chips);
425 	irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw));
426 
427 	return 0;
428 }
429 
430 static const struct irq_domain_ops davinci_gpio_irq_ops = {
431 	.map = davinci_gpio_irq_map,
432 	.xlate = irq_domain_xlate_onetwocell,
433 };
434 
davinci_gpio_get_irq_chip(unsigned int irq)435 static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
436 {
437 	static struct irq_chip_type gpio_unbanked;
438 
439 	gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
440 
441 	return &gpio_unbanked.chip;
442 };
443 
keystone_gpio_get_irq_chip(unsigned int irq)444 static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
445 {
446 	static struct irq_chip gpio_unbanked;
447 
448 	gpio_unbanked = *irq_get_chip(irq);
449 	return &gpio_unbanked;
450 };
451 
452 static const struct of_device_id davinci_gpio_ids[];
453 
454 /*
455  * NOTE:  for suspend/resume, probably best to make a platform_device with
456  * suspend_late/resume_resume calls hooking into results of the set_wake()
457  * calls ... so if no gpios are wakeup events the clock can be disabled,
458  * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
459  * (dm6446) can be set appropriately for GPIOV33 pins.
460  */
461 
davinci_gpio_irq_setup(struct platform_device * pdev)462 static int davinci_gpio_irq_setup(struct platform_device *pdev)
463 {
464 	unsigned	gpio, bank;
465 	int		irq;
466 	struct clk	*clk;
467 	u32		binten = 0;
468 	unsigned	ngpio;
469 	struct device *dev = &pdev->dev;
470 	struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
471 	struct davinci_gpio_regs __iomem *g;
472 	struct irq_domain	*irq_domain = NULL;
473 	struct irq_chip *irq_chip;
474 	struct davinci_gpio_irq_data *irqdata;
475 	gpio_get_irq_chip_cb_t gpio_get_irq_chip;
476 
477 	/*
478 	 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
479 	 */
480 	gpio_get_irq_chip = davinci_gpio_get_irq_chip;
481 	if (dev->of_node)
482 		gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)device_get_match_data(dev);
483 
484 	ngpio = chips->chip.ngpio;
485 
486 	clk = devm_clk_get_enabled(dev, "gpio");
487 	if (IS_ERR(clk)) {
488 		dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk));
489 		return PTR_ERR(clk);
490 	}
491 
492 	if (!chips->gpio_unbanked) {
493 		irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0);
494 		if (irq < 0) {
495 			dev_err(dev, "Couldn't allocate IRQ numbers\n");
496 			return irq;
497 		}
498 
499 		irq_domain = irq_domain_create_legacy(dev_fwnode(dev), ngpio, irq, 0,
500 						      &davinci_gpio_irq_ops, chips);
501 		if (!irq_domain) {
502 			dev_err(dev, "Couldn't register an IRQ domain\n");
503 			return -ENODEV;
504 		}
505 	}
506 
507 	/*
508 	 * Arrange gpiod_to_irq() support, handling either direct IRQs or
509 	 * banked IRQs.  Having GPIOs in the first GPIO bank use direct
510 	 * IRQs, while the others use banked IRQs, would need some setup
511 	 * tweaks to recognize hardware which can do that.
512 	 */
513 	chips->chip.to_irq = gpio_to_irq_banked;
514 	chips->irq_domain = irq_domain;
515 
516 	/*
517 	 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
518 	 * controller only handling trigger modes.  We currently assume no
519 	 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
520 	 */
521 	if (chips->gpio_unbanked) {
522 		/* pass "bank 0" GPIO IRQs to AINTC */
523 		chips->chip.to_irq = gpio_to_irq_unbanked;
524 
525 		binten = GENMASK(chips->gpio_unbanked / 16, 0);
526 
527 		/* AINTC handles mask/unmask; GPIO handles triggering */
528 		irq = chips->irqs[0];
529 		irq_chip = gpio_get_irq_chip(irq);
530 		irq_chip->name = "GPIO-AINTC";
531 		irq_chip->irq_set_type = gpio_irq_type_unbanked;
532 
533 		/* default trigger: both edges */
534 		g = chips->regs[0];
535 		writel_relaxed(~0, &g->set_falling);
536 		writel_relaxed(~0, &g->set_rising);
537 
538 		/* set the direct IRQs up to use that irqchip */
539 		for (gpio = 0; gpio < chips->gpio_unbanked; gpio++) {
540 			irq_set_chip(chips->irqs[gpio], irq_chip);
541 			irq_set_handler_data(chips->irqs[gpio], chips);
542 			irq_set_status_flags(chips->irqs[gpio],
543 					     IRQ_TYPE_EDGE_BOTH);
544 		}
545 
546 		goto done;
547 	}
548 
549 	/*
550 	 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
551 	 * then chain through our own handler.
552 	 */
553 	for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) {
554 		/* disabled by default, enabled only as needed
555 		 * There are register sets for 32 GPIOs. 2 banks of 16
556 		 * GPIOs are covered by each set of registers hence divide by 2
557 		 */
558 		g = chips->regs[bank / 2];
559 		writel_relaxed(~0, &g->clr_falling);
560 		writel_relaxed(~0, &g->clr_rising);
561 
562 		/*
563 		 * Each chip handles 32 gpios, and each irq bank consists of 16
564 		 * gpio irqs. Pass the irq bank's corresponding controller to
565 		 * the chained irq handler.
566 		 */
567 		irqdata = devm_kzalloc(&pdev->dev,
568 				       sizeof(struct
569 					      davinci_gpio_irq_data),
570 					      GFP_KERNEL);
571 		if (!irqdata)
572 			return -ENOMEM;
573 
574 		irqdata->regs = g;
575 		irqdata->bank_num = bank;
576 		irqdata->chip = chips;
577 
578 		irq_set_chained_handler_and_data(chips->irqs[bank],
579 						 gpio_irq_handler, irqdata);
580 
581 		binten |= BIT(bank);
582 	}
583 
584 done:
585 	/*
586 	 * BINTEN -- per-bank interrupt enable. genirq would also let these
587 	 * bits be set/cleared dynamically.
588 	 */
589 	writel_relaxed(binten, gpio_base + BINTEN);
590 
591 	return 0;
592 }
593 
davinci_gpio_save_context(struct davinci_gpio_controller * chips,u32 nbank)594 static void davinci_gpio_save_context(struct davinci_gpio_controller *chips,
595 				      u32 nbank)
596 {
597 	struct davinci_gpio_regs __iomem *g;
598 	struct davinci_gpio_regs *context;
599 	u32 bank;
600 	void __iomem *base;
601 
602 	base = chips->regs[0] - offset_array[0];
603 	chips->binten_context = readl_relaxed(base + BINTEN);
604 
605 	for (bank = 0; bank < nbank; bank++) {
606 		g = chips->regs[bank];
607 		context = &chips->context[bank];
608 		context->dir = readl_relaxed(&g->dir);
609 		context->set_data = readl_relaxed(&g->set_data);
610 		context->set_rising = readl_relaxed(&g->set_rising);
611 		context->set_falling = readl_relaxed(&g->set_falling);
612 	}
613 
614 	/* Clear all interrupt status registers */
615 	writel_relaxed(GENMASK(31, 0), &g->intstat);
616 }
617 
davinci_gpio_restore_context(struct davinci_gpio_controller * chips,u32 nbank)618 static void davinci_gpio_restore_context(struct davinci_gpio_controller *chips,
619 					 u32 nbank)
620 {
621 	struct davinci_gpio_regs __iomem *g;
622 	struct davinci_gpio_regs *context;
623 	u32 bank;
624 	void __iomem *base;
625 
626 	base = chips->regs[0] - offset_array[0];
627 
628 	if (readl_relaxed(base + BINTEN) != chips->binten_context)
629 		writel_relaxed(chips->binten_context, base + BINTEN);
630 
631 	for (bank = 0; bank < nbank; bank++) {
632 		g = chips->regs[bank];
633 		context = &chips->context[bank];
634 		if (readl_relaxed(&g->dir) != context->dir)
635 			writel_relaxed(context->dir, &g->dir);
636 		if (readl_relaxed(&g->set_data) != context->set_data)
637 			writel_relaxed(context->set_data, &g->set_data);
638 		if (readl_relaxed(&g->set_rising) != context->set_rising)
639 			writel_relaxed(context->set_rising, &g->set_rising);
640 		if (readl_relaxed(&g->set_falling) != context->set_falling)
641 			writel_relaxed(context->set_falling, &g->set_falling);
642 	}
643 }
644 
davinci_gpio_suspend(struct device * dev)645 static int davinci_gpio_suspend(struct device *dev)
646 {
647 	struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
648 	u32 nbank = DIV_ROUND_UP(chips->chip.ngpio, 32);
649 
650 	davinci_gpio_save_context(chips, nbank);
651 
652 	return 0;
653 }
654 
davinci_gpio_resume(struct device * dev)655 static int davinci_gpio_resume(struct device *dev)
656 {
657 	struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
658 	u32 nbank = DIV_ROUND_UP(chips->chip.ngpio, 32);
659 
660 	davinci_gpio_restore_context(chips, nbank);
661 
662 	return 0;
663 }
664 
665 static DEFINE_SIMPLE_DEV_PM_OPS(davinci_gpio_dev_pm_ops, davinci_gpio_suspend,
666 			 davinci_gpio_resume);
667 
668 static const struct of_device_id davinci_gpio_ids[] = {
669 	{ .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
670 	{ .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip},
671 	{ .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
672 	{ /* sentinel */ },
673 };
674 MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
675 
676 static struct platform_driver davinci_gpio_driver = {
677 	.probe		= davinci_gpio_probe,
678 	.driver		= {
679 		.name		= "davinci_gpio",
680 		.pm = pm_sleep_ptr(&davinci_gpio_dev_pm_ops),
681 		.of_match_table	= davinci_gpio_ids,
682 	},
683 };
684 
685 /*
686  * GPIO driver registration needs to be done before machine_init functions
687  * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
688  */
davinci_gpio_drv_reg(void)689 static int __init davinci_gpio_drv_reg(void)
690 {
691 	return platform_driver_register(&davinci_gpio_driver);
692 }
693 postcore_initcall(davinci_gpio_drv_reg);
694 
davinci_gpio_exit(void)695 static void __exit davinci_gpio_exit(void)
696 {
697 	platform_driver_unregister(&davinci_gpio_driver);
698 }
699 module_exit(davinci_gpio_exit);
700 
701 MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
702 MODULE_DESCRIPTION("DAVINCI GPIO driver");
703 MODULE_LICENSE("GPL");
704 MODULE_ALIAS("platform:gpio-davinci");
705