xref: /openbmc/linux/drivers/gpio/gpio-omap.c (revision 24b1944f) 
1 /*
2  * Support functions for OMAP GPIO
3  *
4  * Copyright (C) 2003-2005 Nokia Corporation
5  * Written by Juha Yrjölä <juha.yrjola@nokia.com>
6  *
7  * Copyright (C) 2009 Texas Instruments
8  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/interrupt.h>
18 #include <linux/syscore_ops.h>
19 #include <linux/err.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22 #include <linux/device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/pm.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27 #include <linux/irqdomain.h>
28 #include <linux/irqchip/chained_irq.h>
29 #include <linux/gpio.h>
30 #include <linux/platform_data/gpio-omap.h>
31 
32 #define OFF_MODE	1
33 
34 static LIST_HEAD(omap_gpio_list);
35 
36 struct gpio_regs {
37 	u32 irqenable1;
38 	u32 irqenable2;
39 	u32 wake_en;
40 	u32 ctrl;
41 	u32 oe;
42 	u32 leveldetect0;
43 	u32 leveldetect1;
44 	u32 risingdetect;
45 	u32 fallingdetect;
46 	u32 dataout;
47 	u32 debounce;
48 	u32 debounce_en;
49 };
50 
51 struct gpio_bank {
52 	struct list_head node;
53 	void __iomem *base;
54 	u16 irq;
55 	struct irq_domain *domain;
56 	u32 non_wakeup_gpios;
57 	u32 enabled_non_wakeup_gpios;
58 	struct gpio_regs context;
59 	u32 saved_datain;
60 	u32 level_mask;
61 	u32 toggle_mask;
62 	spinlock_t lock;
63 	struct gpio_chip chip;
64 	struct clk *dbck;
65 	u32 mod_usage;
66 	u32 dbck_enable_mask;
67 	bool dbck_enabled;
68 	struct device *dev;
69 	bool is_mpuio;
70 	bool dbck_flag;
71 	bool loses_context;
72 	bool context_valid;
73 	int stride;
74 	u32 width;
75 	int context_loss_count;
76 	int power_mode;
77 	bool workaround_enabled;
78 
79 	void (*set_dataout)(struct gpio_bank *bank, int gpio, int enable);
80 	int (*get_context_loss_count)(struct device *dev);
81 
82 	struct omap_gpio_reg_offs *regs;
83 };
84 
85 #define GPIO_INDEX(bank, gpio) (gpio % bank->width)
86 #define GPIO_BIT(bank, gpio) (1 << GPIO_INDEX(bank, gpio))
87 #define GPIO_MOD_CTRL_BIT	BIT(0)
88 
89 static int irq_to_gpio(struct gpio_bank *bank, unsigned int gpio_irq)
90 {
91 	return bank->chip.base + gpio_irq;
92 }
93 
94 static int omap_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
95 {
96 	struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
97 
98 	return irq_find_mapping(bank->domain, offset);
99 }
100 
101 static void _set_gpio_direction(struct gpio_bank *bank, int gpio, int is_input)
102 {
103 	void __iomem *reg = bank->base;
104 	u32 l;
105 
106 	reg += bank->regs->direction;
107 	l = __raw_readl(reg);
108 	if (is_input)
109 		l |= 1 << gpio;
110 	else
111 		l &= ~(1 << gpio);
112 	__raw_writel(l, reg);
113 	bank->context.oe = l;
114 }
115 
116 
117 /* set data out value using dedicate set/clear register */
118 static void _set_gpio_dataout_reg(struct gpio_bank *bank, int gpio, int enable)
119 {
120 	void __iomem *reg = bank->base;
121 	u32 l = GPIO_BIT(bank, gpio);
122 
123 	if (enable) {
124 		reg += bank->regs->set_dataout;
125 		bank->context.dataout |= l;
126 	} else {
127 		reg += bank->regs->clr_dataout;
128 		bank->context.dataout &= ~l;
129 	}
130 
131 	__raw_writel(l, reg);
132 }
133 
134 /* set data out value using mask register */
135 static void _set_gpio_dataout_mask(struct gpio_bank *bank, int gpio, int enable)
136 {
137 	void __iomem *reg = bank->base + bank->regs->dataout;
138 	u32 gpio_bit = GPIO_BIT(bank, gpio);
139 	u32 l;
140 
141 	l = __raw_readl(reg);
142 	if (enable)
143 		l |= gpio_bit;
144 	else
145 		l &= ~gpio_bit;
146 	__raw_writel(l, reg);
147 	bank->context.dataout = l;
148 }
149 
150 static int _get_gpio_datain(struct gpio_bank *bank, int offset)
151 {
152 	void __iomem *reg = bank->base + bank->regs->datain;
153 
154 	return (__raw_readl(reg) & (1 << offset)) != 0;
155 }
156 
157 static int _get_gpio_dataout(struct gpio_bank *bank, int offset)
158 {
159 	void __iomem *reg = bank->base + bank->regs->dataout;
160 
161 	return (__raw_readl(reg) & (1 << offset)) != 0;
162 }
163 
164 static inline void _gpio_rmw(void __iomem *base, u32 reg, u32 mask, bool set)
165 {
166 	int l = __raw_readl(base + reg);
167 
168 	if (set)
169 		l |= mask;
170 	else
171 		l &= ~mask;
172 
173 	__raw_writel(l, base + reg);
174 }
175 
176 static inline void _gpio_dbck_enable(struct gpio_bank *bank)
177 {
178 	if (bank->dbck_enable_mask && !bank->dbck_enabled) {
179 		clk_enable(bank->dbck);
180 		bank->dbck_enabled = true;
181 
182 		__raw_writel(bank->dbck_enable_mask,
183 			     bank->base + bank->regs->debounce_en);
184 	}
185 }
186 
187 static inline void _gpio_dbck_disable(struct gpio_bank *bank)
188 {
189 	if (bank->dbck_enable_mask && bank->dbck_enabled) {
190 		/*
191 		 * Disable debounce before cutting it's clock. If debounce is
192 		 * enabled but the clock is not, GPIO module seems to be unable
193 		 * to detect events and generate interrupts at least on OMAP3.
194 		 */
195 		__raw_writel(0, bank->base + bank->regs->debounce_en);
196 
197 		clk_disable(bank->dbck);
198 		bank->dbck_enabled = false;
199 	}
200 }
201 
202 /**
203  * _set_gpio_debounce - low level gpio debounce time
204  * @bank: the gpio bank we're acting upon
205  * @gpio: the gpio number on this @gpio
206  * @debounce: debounce time to use
207  *
208  * OMAP's debounce time is in 31us steps so we need
209  * to convert and round up to the closest unit.
210  */
211 static void _set_gpio_debounce(struct gpio_bank *bank, unsigned gpio,
212 		unsigned debounce)
213 {
214 	void __iomem		*reg;
215 	u32			val;
216 	u32			l;
217 
218 	if (!bank->dbck_flag)
219 		return;
220 
221 	if (debounce < 32)
222 		debounce = 0x01;
223 	else if (debounce > 7936)
224 		debounce = 0xff;
225 	else
226 		debounce = (debounce / 0x1f) - 1;
227 
228 	l = GPIO_BIT(bank, gpio);
229 
230 	clk_enable(bank->dbck);
231 	reg = bank->base + bank->regs->debounce;
232 	__raw_writel(debounce, reg);
233 
234 	reg = bank->base + bank->regs->debounce_en;
235 	val = __raw_readl(reg);
236 
237 	if (debounce)
238 		val |= l;
239 	else
240 		val &= ~l;
241 	bank->dbck_enable_mask = val;
242 
243 	__raw_writel(val, reg);
244 	clk_disable(bank->dbck);
245 	/*
246 	 * Enable debounce clock per module.
247 	 * This call is mandatory because in omap_gpio_request() when
248 	 * *_runtime_get_sync() is called,  _gpio_dbck_enable() within
249 	 * runtime callbck fails to turn on dbck because dbck_enable_mask
250 	 * used within _gpio_dbck_enable() is still not initialized at
251 	 * that point. Therefore we have to enable dbck here.
252 	 */
253 	_gpio_dbck_enable(bank);
254 	if (bank->dbck_enable_mask) {
255 		bank->context.debounce = debounce;
256 		bank->context.debounce_en = val;
257 	}
258 }
259 
260 /**
261  * _clear_gpio_debounce - clear debounce settings for a gpio
262  * @bank: the gpio bank we're acting upon
263  * @gpio: the gpio number on this @gpio
264  *
265  * If a gpio is using debounce, then clear the debounce enable bit and if
266  * this is the only gpio in this bank using debounce, then clear the debounce
267  * time too. The debounce clock will also be disabled when calling this function
268  * if this is the only gpio in the bank using debounce.
269  */
270 static void _clear_gpio_debounce(struct gpio_bank *bank, unsigned gpio)
271 {
272 	u32 gpio_bit = GPIO_BIT(bank, gpio);
273 
274 	if (!bank->dbck_flag)
275 		return;
276 
277 	if (!(bank->dbck_enable_mask & gpio_bit))
278 		return;
279 
280 	bank->dbck_enable_mask &= ~gpio_bit;
281 	bank->context.debounce_en &= ~gpio_bit;
282 	__raw_writel(bank->context.debounce_en,
283 		     bank->base + bank->regs->debounce_en);
284 
285 	if (!bank->dbck_enable_mask) {
286 		bank->context.debounce = 0;
287 		__raw_writel(bank->context.debounce, bank->base +
288 			     bank->regs->debounce);
289 		clk_disable(bank->dbck);
290 		bank->dbck_enabled = false;
291 	}
292 }
293 
294 static inline void set_gpio_trigger(struct gpio_bank *bank, int gpio,
295 						unsigned trigger)
296 {
297 	void __iomem *base = bank->base;
298 	u32 gpio_bit = 1 << gpio;
299 
300 	_gpio_rmw(base, bank->regs->leveldetect0, gpio_bit,
301 		  trigger & IRQ_TYPE_LEVEL_LOW);
302 	_gpio_rmw(base, bank->regs->leveldetect1, gpio_bit,
303 		  trigger & IRQ_TYPE_LEVEL_HIGH);
304 	_gpio_rmw(base, bank->regs->risingdetect, gpio_bit,
305 		  trigger & IRQ_TYPE_EDGE_RISING);
306 	_gpio_rmw(base, bank->regs->fallingdetect, gpio_bit,
307 		  trigger & IRQ_TYPE_EDGE_FALLING);
308 
309 	bank->context.leveldetect0 =
310 			__raw_readl(bank->base + bank->regs->leveldetect0);
311 	bank->context.leveldetect1 =
312 			__raw_readl(bank->base + bank->regs->leveldetect1);
313 	bank->context.risingdetect =
314 			__raw_readl(bank->base + bank->regs->risingdetect);
315 	bank->context.fallingdetect =
316 			__raw_readl(bank->base + bank->regs->fallingdetect);
317 
318 	if (likely(!(bank->non_wakeup_gpios & gpio_bit))) {
319 		_gpio_rmw(base, bank->regs->wkup_en, gpio_bit, trigger != 0);
320 		bank->context.wake_en =
321 			__raw_readl(bank->base + bank->regs->wkup_en);
322 	}
323 
324 	/* This part needs to be executed always for OMAP{34xx, 44xx} */
325 	if (!bank->regs->irqctrl) {
326 		/* On omap24xx proceed only when valid GPIO bit is set */
327 		if (bank->non_wakeup_gpios) {
328 			if (!(bank->non_wakeup_gpios & gpio_bit))
329 				goto exit;
330 		}
331 
332 		/*
333 		 * Log the edge gpio and manually trigger the IRQ
334 		 * after resume if the input level changes
335 		 * to avoid irq lost during PER RET/OFF mode
336 		 * Applies for omap2 non-wakeup gpio and all omap3 gpios
337 		 */
338 		if (trigger & IRQ_TYPE_EDGE_BOTH)
339 			bank->enabled_non_wakeup_gpios |= gpio_bit;
340 		else
341 			bank->enabled_non_wakeup_gpios &= ~gpio_bit;
342 	}
343 
344 exit:
345 	bank->level_mask =
346 		__raw_readl(bank->base + bank->regs->leveldetect0) |
347 		__raw_readl(bank->base + bank->regs->leveldetect1);
348 }
349 
350 #ifdef CONFIG_ARCH_OMAP1
351 /*
352  * This only applies to chips that can't do both rising and falling edge
353  * detection at once.  For all other chips, this function is a noop.
354  */
355 static void _toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio)
356 {
357 	void __iomem *reg = bank->base;
358 	u32 l = 0;
359 
360 	if (!bank->regs->irqctrl)
361 		return;
362 
363 	reg += bank->regs->irqctrl;
364 
365 	l = __raw_readl(reg);
366 	if ((l >> gpio) & 1)
367 		l &= ~(1 << gpio);
368 	else
369 		l |= 1 << gpio;
370 
371 	__raw_writel(l, reg);
372 }
373 #else
374 static void _toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio) {}
375 #endif
376 
377 static int _set_gpio_triggering(struct gpio_bank *bank, int gpio,
378 							unsigned trigger)
379 {
380 	void __iomem *reg = bank->base;
381 	void __iomem *base = bank->base;
382 	u32 l = 0;
383 
384 	if (bank->regs->leveldetect0 && bank->regs->wkup_en) {
385 		set_gpio_trigger(bank, gpio, trigger);
386 	} else if (bank->regs->irqctrl) {
387 		reg += bank->regs->irqctrl;
388 
389 		l = __raw_readl(reg);
390 		if ((trigger & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
391 			bank->toggle_mask |= 1 << gpio;
392 		if (trigger & IRQ_TYPE_EDGE_RISING)
393 			l |= 1 << gpio;
394 		else if (trigger & IRQ_TYPE_EDGE_FALLING)
395 			l &= ~(1 << gpio);
396 		else
397 			return -EINVAL;
398 
399 		__raw_writel(l, reg);
400 	} else if (bank->regs->edgectrl1) {
401 		if (gpio & 0x08)
402 			reg += bank->regs->edgectrl2;
403 		else
404 			reg += bank->regs->edgectrl1;
405 
406 		gpio &= 0x07;
407 		l = __raw_readl(reg);
408 		l &= ~(3 << (gpio << 1));
409 		if (trigger & IRQ_TYPE_EDGE_RISING)
410 			l |= 2 << (gpio << 1);
411 		if (trigger & IRQ_TYPE_EDGE_FALLING)
412 			l |= 1 << (gpio << 1);
413 
414 		/* Enable wake-up during idle for dynamic tick */
415 		_gpio_rmw(base, bank->regs->wkup_en, 1 << gpio, trigger);
416 		bank->context.wake_en =
417 			__raw_readl(bank->base + bank->regs->wkup_en);
418 		__raw_writel(l, reg);
419 	}
420 	return 0;
421 }
422 
423 static int gpio_irq_type(struct irq_data *d, unsigned type)
424 {
425 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
426 	unsigned gpio = 0;
427 	int retval;
428 	unsigned long flags;
429 
430 	if (WARN_ON(!bank->mod_usage))
431 		return -EINVAL;
432 
433 #ifdef CONFIG_ARCH_OMAP1
434 	if (d->irq > IH_MPUIO_BASE)
435 		gpio = OMAP_MPUIO(d->irq - IH_MPUIO_BASE);
436 #endif
437 
438 	if (!gpio)
439 		gpio = irq_to_gpio(bank, d->hwirq);
440 
441 	if (type & ~IRQ_TYPE_SENSE_MASK)
442 		return -EINVAL;
443 
444 	if (!bank->regs->leveldetect0 &&
445 		(type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH)))
446 		return -EINVAL;
447 
448 	spin_lock_irqsave(&bank->lock, flags);
449 	retval = _set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), type);
450 	spin_unlock_irqrestore(&bank->lock, flags);
451 
452 	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
453 		__irq_set_handler_locked(d->irq, handle_level_irq);
454 	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
455 		__irq_set_handler_locked(d->irq, handle_edge_irq);
456 
457 	return retval;
458 }
459 
460 static void _clear_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
461 {
462 	void __iomem *reg = bank->base;
463 
464 	reg += bank->regs->irqstatus;
465 	__raw_writel(gpio_mask, reg);
466 
467 	/* Workaround for clearing DSP GPIO interrupts to allow retention */
468 	if (bank->regs->irqstatus2) {
469 		reg = bank->base + bank->regs->irqstatus2;
470 		__raw_writel(gpio_mask, reg);
471 	}
472 
473 	/* Flush posted write for the irq status to avoid spurious interrupts */
474 	__raw_readl(reg);
475 }
476 
477 static inline void _clear_gpio_irqstatus(struct gpio_bank *bank, int gpio)
478 {
479 	_clear_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
480 }
481 
482 static u32 _get_gpio_irqbank_mask(struct gpio_bank *bank)
483 {
484 	void __iomem *reg = bank->base;
485 	u32 l;
486 	u32 mask = (1 << bank->width) - 1;
487 
488 	reg += bank->regs->irqenable;
489 	l = __raw_readl(reg);
490 	if (bank->regs->irqenable_inv)
491 		l = ~l;
492 	l &= mask;
493 	return l;
494 }
495 
496 static void _enable_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
497 {
498 	void __iomem *reg = bank->base;
499 	u32 l;
500 
501 	if (bank->regs->set_irqenable) {
502 		reg += bank->regs->set_irqenable;
503 		l = gpio_mask;
504 		bank->context.irqenable1 |= gpio_mask;
505 	} else {
506 		reg += bank->regs->irqenable;
507 		l = __raw_readl(reg);
508 		if (bank->regs->irqenable_inv)
509 			l &= ~gpio_mask;
510 		else
511 			l |= gpio_mask;
512 		bank->context.irqenable1 = l;
513 	}
514 
515 	__raw_writel(l, reg);
516 }
517 
518 static void _disable_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
519 {
520 	void __iomem *reg = bank->base;
521 	u32 l;
522 
523 	if (bank->regs->clr_irqenable) {
524 		reg += bank->regs->clr_irqenable;
525 		l = gpio_mask;
526 		bank->context.irqenable1 &= ~gpio_mask;
527 	} else {
528 		reg += bank->regs->irqenable;
529 		l = __raw_readl(reg);
530 		if (bank->regs->irqenable_inv)
531 			l |= gpio_mask;
532 		else
533 			l &= ~gpio_mask;
534 		bank->context.irqenable1 = l;
535 	}
536 
537 	__raw_writel(l, reg);
538 }
539 
540 static inline void _set_gpio_irqenable(struct gpio_bank *bank, int gpio, int enable)
541 {
542 	if (enable)
543 		_enable_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
544 	else
545 		_disable_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
546 }
547 
548 /*
549  * Note that ENAWAKEUP needs to be enabled in GPIO_SYSCONFIG register.
550  * 1510 does not seem to have a wake-up register. If JTAG is connected
551  * to the target, system will wake up always on GPIO events. While
552  * system is running all registered GPIO interrupts need to have wake-up
553  * enabled. When system is suspended, only selected GPIO interrupts need
554  * to have wake-up enabled.
555  */
556 static int _set_gpio_wakeup(struct gpio_bank *bank, int gpio, int enable)
557 {
558 	u32 gpio_bit = GPIO_BIT(bank, gpio);
559 	unsigned long flags;
560 
561 	if (bank->non_wakeup_gpios & gpio_bit) {
562 		dev_err(bank->dev,
563 			"Unable to modify wakeup on non-wakeup GPIO%d\n", gpio);
564 		return -EINVAL;
565 	}
566 
567 	spin_lock_irqsave(&bank->lock, flags);
568 	if (enable)
569 		bank->context.wake_en |= gpio_bit;
570 	else
571 		bank->context.wake_en &= ~gpio_bit;
572 
573 	__raw_writel(bank->context.wake_en, bank->base + bank->regs->wkup_en);
574 	spin_unlock_irqrestore(&bank->lock, flags);
575 
576 	return 0;
577 }
578 
579 static void _reset_gpio(struct gpio_bank *bank, int gpio)
580 {
581 	_set_gpio_direction(bank, GPIO_INDEX(bank, gpio), 1);
582 	_set_gpio_irqenable(bank, gpio, 0);
583 	_clear_gpio_irqstatus(bank, gpio);
584 	_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE);
585 	_clear_gpio_debounce(bank, gpio);
586 }
587 
588 /* Use disable_irq_wake() and enable_irq_wake() functions from drivers */
589 static int gpio_wake_enable(struct irq_data *d, unsigned int enable)
590 {
591 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
592 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
593 
594 	return _set_gpio_wakeup(bank, gpio, enable);
595 }
596 
597 static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
598 {
599 	struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
600 	unsigned long flags;
601 
602 	/*
603 	 * If this is the first gpio_request for the bank,
604 	 * enable the bank module.
605 	 */
606 	if (!bank->mod_usage)
607 		pm_runtime_get_sync(bank->dev);
608 
609 	spin_lock_irqsave(&bank->lock, flags);
610 	/* Set trigger to none. You need to enable the desired trigger with
611 	 * request_irq() or set_irq_type().
612 	 */
613 	_set_gpio_triggering(bank, offset, IRQ_TYPE_NONE);
614 
615 	if (bank->regs->pinctrl) {
616 		void __iomem *reg = bank->base + bank->regs->pinctrl;
617 
618 		/* Claim the pin for MPU */
619 		__raw_writel(__raw_readl(reg) | (1 << offset), reg);
620 	}
621 
622 	if (bank->regs->ctrl && !bank->mod_usage) {
623 		void __iomem *reg = bank->base + bank->regs->ctrl;
624 		u32 ctrl;
625 
626 		ctrl = __raw_readl(reg);
627 		/* Module is enabled, clocks are not gated */
628 		ctrl &= ~GPIO_MOD_CTRL_BIT;
629 		__raw_writel(ctrl, reg);
630 		bank->context.ctrl = ctrl;
631 	}
632 
633 	bank->mod_usage |= 1 << offset;
634 
635 	spin_unlock_irqrestore(&bank->lock, flags);
636 
637 	return 0;
638 }
639 
640 static void omap_gpio_free(struct gpio_chip *chip, unsigned offset)
641 {
642 	struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
643 	void __iomem *base = bank->base;
644 	unsigned long flags;
645 
646 	spin_lock_irqsave(&bank->lock, flags);
647 
648 	if (bank->regs->wkup_en) {
649 		/* Disable wake-up during idle for dynamic tick */
650 		_gpio_rmw(base, bank->regs->wkup_en, 1 << offset, 0);
651 		bank->context.wake_en =
652 			__raw_readl(bank->base + bank->regs->wkup_en);
653 	}
654 
655 	bank->mod_usage &= ~(1 << offset);
656 
657 	if (bank->regs->ctrl && !bank->mod_usage) {
658 		void __iomem *reg = bank->base + bank->regs->ctrl;
659 		u32 ctrl;
660 
661 		ctrl = __raw_readl(reg);
662 		/* Module is disabled, clocks are gated */
663 		ctrl |= GPIO_MOD_CTRL_BIT;
664 		__raw_writel(ctrl, reg);
665 		bank->context.ctrl = ctrl;
666 	}
667 
668 	_reset_gpio(bank, bank->chip.base + offset);
669 	spin_unlock_irqrestore(&bank->lock, flags);
670 
671 	/*
672 	 * If this is the last gpio to be freed in the bank,
673 	 * disable the bank module.
674 	 */
675 	if (!bank->mod_usage)
676 		pm_runtime_put(bank->dev);
677 }
678 
679 /*
680  * We need to unmask the GPIO bank interrupt as soon as possible to
681  * avoid missing GPIO interrupts for other lines in the bank.
682  * Then we need to mask-read-clear-unmask the triggered GPIO lines
683  * in the bank to avoid missing nested interrupts for a GPIO line.
684  * If we wait to unmask individual GPIO lines in the bank after the
685  * line's interrupt handler has been run, we may miss some nested
686  * interrupts.
687  */
688 static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
689 {
690 	void __iomem *isr_reg = NULL;
691 	u32 isr;
692 	unsigned int bit;
693 	struct gpio_bank *bank;
694 	int unmasked = 0;
695 	struct irq_chip *chip = irq_desc_get_chip(desc);
696 
697 	chained_irq_enter(chip, desc);
698 
699 	bank = irq_get_handler_data(irq);
700 	isr_reg = bank->base + bank->regs->irqstatus;
701 	pm_runtime_get_sync(bank->dev);
702 
703 	if (WARN_ON(!isr_reg))
704 		goto exit;
705 
706 	while (1) {
707 		u32 isr_saved, level_mask = 0;
708 		u32 enabled;
709 
710 		enabled = _get_gpio_irqbank_mask(bank);
711 		isr_saved = isr = __raw_readl(isr_reg) & enabled;
712 
713 		if (bank->level_mask)
714 			level_mask = bank->level_mask & enabled;
715 
716 		/* clear edge sensitive interrupts before handler(s) are
717 		called so that we don't miss any interrupt occurred while
718 		executing them */
719 		_disable_gpio_irqbank(bank, isr_saved & ~level_mask);
720 		_clear_gpio_irqbank(bank, isr_saved & ~level_mask);
721 		_enable_gpio_irqbank(bank, isr_saved & ~level_mask);
722 
723 		/* if there is only edge sensitive GPIO pin interrupts
724 		configured, we could unmask GPIO bank interrupt immediately */
725 		if (!level_mask && !unmasked) {
726 			unmasked = 1;
727 			chained_irq_exit(chip, desc);
728 		}
729 
730 		if (!isr)
731 			break;
732 
733 		while (isr) {
734 			bit = __ffs(isr);
735 			isr &= ~(1 << bit);
736 
737 			/*
738 			 * Some chips can't respond to both rising and falling
739 			 * at the same time.  If this irq was requested with
740 			 * both flags, we need to flip the ICR data for the IRQ
741 			 * to respond to the IRQ for the opposite direction.
742 			 * This will be indicated in the bank toggle_mask.
743 			 */
744 			if (bank->toggle_mask & (1 << bit))
745 				_toggle_gpio_edge_triggering(bank, bit);
746 
747 			generic_handle_irq(irq_find_mapping(bank->domain, bit));
748 		}
749 	}
750 	/* if bank has any level sensitive GPIO pin interrupt
751 	configured, we must unmask the bank interrupt only after
752 	handler(s) are executed in order to avoid spurious bank
753 	interrupt */
754 exit:
755 	if (!unmasked)
756 		chained_irq_exit(chip, desc);
757 	pm_runtime_put(bank->dev);
758 }
759 
760 static void gpio_irq_shutdown(struct irq_data *d)
761 {
762 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
763 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
764 	unsigned long flags;
765 
766 	spin_lock_irqsave(&bank->lock, flags);
767 	_reset_gpio(bank, gpio);
768 	spin_unlock_irqrestore(&bank->lock, flags);
769 }
770 
771 static void gpio_ack_irq(struct irq_data *d)
772 {
773 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
774 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
775 
776 	_clear_gpio_irqstatus(bank, gpio);
777 }
778 
779 static void gpio_mask_irq(struct irq_data *d)
780 {
781 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
782 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
783 	unsigned long flags;
784 
785 	spin_lock_irqsave(&bank->lock, flags);
786 	_set_gpio_irqenable(bank, gpio, 0);
787 	_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE);
788 	spin_unlock_irqrestore(&bank->lock, flags);
789 }
790 
791 static void gpio_unmask_irq(struct irq_data *d)
792 {
793 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
794 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
795 	unsigned int irq_mask = GPIO_BIT(bank, gpio);
796 	u32 trigger = irqd_get_trigger_type(d);
797 	unsigned long flags;
798 
799 	spin_lock_irqsave(&bank->lock, flags);
800 	if (trigger)
801 		_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), trigger);
802 
803 	/* For level-triggered GPIOs, the clearing must be done after
804 	 * the HW source is cleared, thus after the handler has run */
805 	if (bank->level_mask & irq_mask) {
806 		_set_gpio_irqenable(bank, gpio, 0);
807 		_clear_gpio_irqstatus(bank, gpio);
808 	}
809 
810 	_set_gpio_irqenable(bank, gpio, 1);
811 	spin_unlock_irqrestore(&bank->lock, flags);
812 }
813 
814 static struct irq_chip gpio_irq_chip = {
815 	.name		= "GPIO",
816 	.irq_shutdown	= gpio_irq_shutdown,
817 	.irq_ack	= gpio_ack_irq,
818 	.irq_mask	= gpio_mask_irq,
819 	.irq_unmask	= gpio_unmask_irq,
820 	.irq_set_type	= gpio_irq_type,
821 	.irq_set_wake	= gpio_wake_enable,
822 };
823 
824 /*---------------------------------------------------------------------*/
825 
826 static int omap_mpuio_suspend_noirq(struct device *dev)
827 {
828 	struct platform_device *pdev = to_platform_device(dev);
829 	struct gpio_bank	*bank = platform_get_drvdata(pdev);
830 	void __iomem		*mask_reg = bank->base +
831 					OMAP_MPUIO_GPIO_MASKIT / bank->stride;
832 	unsigned long		flags;
833 
834 	spin_lock_irqsave(&bank->lock, flags);
835 	__raw_writel(0xffff & ~bank->context.wake_en, mask_reg);
836 	spin_unlock_irqrestore(&bank->lock, flags);
837 
838 	return 0;
839 }
840 
841 static int omap_mpuio_resume_noirq(struct device *dev)
842 {
843 	struct platform_device *pdev = to_platform_device(dev);
844 	struct gpio_bank	*bank = platform_get_drvdata(pdev);
845 	void __iomem		*mask_reg = bank->base +
846 					OMAP_MPUIO_GPIO_MASKIT / bank->stride;
847 	unsigned long		flags;
848 
849 	spin_lock_irqsave(&bank->lock, flags);
850 	__raw_writel(bank->context.wake_en, mask_reg);
851 	spin_unlock_irqrestore(&bank->lock, flags);
852 
853 	return 0;
854 }
855 
856 static const struct dev_pm_ops omap_mpuio_dev_pm_ops = {
857 	.suspend_noirq = omap_mpuio_suspend_noirq,
858 	.resume_noirq = omap_mpuio_resume_noirq,
859 };
860 
861 /* use platform_driver for this. */
862 static struct platform_driver omap_mpuio_driver = {
863 	.driver		= {
864 		.name	= "mpuio",
865 		.pm	= &omap_mpuio_dev_pm_ops,
866 	},
867 };
868 
869 static struct platform_device omap_mpuio_device = {
870 	.name		= "mpuio",
871 	.id		= -1,
872 	.dev = {
873 		.driver = &omap_mpuio_driver.driver,
874 	}
875 	/* could list the /proc/iomem resources */
876 };
877 
878 static inline void mpuio_init(struct gpio_bank *bank)
879 {
880 	platform_set_drvdata(&omap_mpuio_device, bank);
881 
882 	if (platform_driver_register(&omap_mpuio_driver) == 0)
883 		(void) platform_device_register(&omap_mpuio_device);
884 }
885 
886 /*---------------------------------------------------------------------*/
887 
888 static int gpio_input(struct gpio_chip *chip, unsigned offset)
889 {
890 	struct gpio_bank *bank;
891 	unsigned long flags;
892 
893 	bank = container_of(chip, struct gpio_bank, chip);
894 	spin_lock_irqsave(&bank->lock, flags);
895 	_set_gpio_direction(bank, offset, 1);
896 	spin_unlock_irqrestore(&bank->lock, flags);
897 	return 0;
898 }
899 
900 static int gpio_is_input(struct gpio_bank *bank, int mask)
901 {
902 	void __iomem *reg = bank->base + bank->regs->direction;
903 
904 	return __raw_readl(reg) & mask;
905 }
906 
907 static int gpio_get(struct gpio_chip *chip, unsigned offset)
908 {
909 	struct gpio_bank *bank;
910 	u32 mask;
911 
912 	bank = container_of(chip, struct gpio_bank, chip);
913 	mask = (1 << offset);
914 
915 	if (gpio_is_input(bank, mask))
916 		return _get_gpio_datain(bank, offset);
917 	else
918 		return _get_gpio_dataout(bank, offset);
919 }
920 
921 static int gpio_output(struct gpio_chip *chip, unsigned offset, int value)
922 {
923 	struct gpio_bank *bank;
924 	unsigned long flags;
925 
926 	bank = container_of(chip, struct gpio_bank, chip);
927 	spin_lock_irqsave(&bank->lock, flags);
928 	bank->set_dataout(bank, offset, value);
929 	_set_gpio_direction(bank, offset, 0);
930 	spin_unlock_irqrestore(&bank->lock, flags);
931 	return 0;
932 }
933 
934 static int gpio_debounce(struct gpio_chip *chip, unsigned offset,
935 		unsigned debounce)
936 {
937 	struct gpio_bank *bank;
938 	unsigned long flags;
939 
940 	bank = container_of(chip, struct gpio_bank, chip);
941 
942 	spin_lock_irqsave(&bank->lock, flags);
943 	_set_gpio_debounce(bank, offset, debounce);
944 	spin_unlock_irqrestore(&bank->lock, flags);
945 
946 	return 0;
947 }
948 
949 static void gpio_set(struct gpio_chip *chip, unsigned offset, int value)
950 {
951 	struct gpio_bank *bank;
952 	unsigned long flags;
953 
954 	bank = container_of(chip, struct gpio_bank, chip);
955 	spin_lock_irqsave(&bank->lock, flags);
956 	bank->set_dataout(bank, offset, value);
957 	spin_unlock_irqrestore(&bank->lock, flags);
958 }
959 
960 /*---------------------------------------------------------------------*/
961 
962 static void __init omap_gpio_show_rev(struct gpio_bank *bank)
963 {
964 	static bool called;
965 	u32 rev;
966 
967 	if (called || bank->regs->revision == USHRT_MAX)
968 		return;
969 
970 	rev = __raw_readw(bank->base + bank->regs->revision);
971 	pr_info("OMAP GPIO hardware version %d.%d\n",
972 		(rev >> 4) & 0x0f, rev & 0x0f);
973 
974 	called = true;
975 }
976 
977 /* This lock class tells lockdep that GPIO irqs are in a different
978  * category than their parents, so it won't report false recursion.
979  */
980 static struct lock_class_key gpio_lock_class;
981 
982 static void omap_gpio_mod_init(struct gpio_bank *bank)
983 {
984 	void __iomem *base = bank->base;
985 	u32 l = 0xffffffff;
986 
987 	if (bank->width == 16)
988 		l = 0xffff;
989 
990 	if (bank->is_mpuio) {
991 		__raw_writel(l, bank->base + bank->regs->irqenable);
992 		return;
993 	}
994 
995 	_gpio_rmw(base, bank->regs->irqenable, l, bank->regs->irqenable_inv);
996 	_gpio_rmw(base, bank->regs->irqstatus, l, !bank->regs->irqenable_inv);
997 	if (bank->regs->debounce_en)
998 		__raw_writel(0, base + bank->regs->debounce_en);
999 
1000 	/* Save OE default value (0xffffffff) in the context */
1001 	bank->context.oe = __raw_readl(bank->base + bank->regs->direction);
1002 	 /* Initialize interface clk ungated, module enabled */
1003 	if (bank->regs->ctrl)
1004 		__raw_writel(0, base + bank->regs->ctrl);
1005 
1006 	bank->dbck = clk_get(bank->dev, "dbclk");
1007 	if (IS_ERR(bank->dbck))
1008 		dev_err(bank->dev, "Could not get gpio dbck\n");
1009 }
1010 
1011 static void
1012 omap_mpuio_alloc_gc(struct gpio_bank *bank, unsigned int irq_start,
1013 		    unsigned int num)
1014 {
1015 	struct irq_chip_generic *gc;
1016 	struct irq_chip_type *ct;
1017 
1018 	gc = irq_alloc_generic_chip("MPUIO", 1, irq_start, bank->base,
1019 				    handle_simple_irq);
1020 	if (!gc) {
1021 		dev_err(bank->dev, "Memory alloc failed for gc\n");
1022 		return;
1023 	}
1024 
1025 	ct = gc->chip_types;
1026 
1027 	/* NOTE: No ack required, reading IRQ status clears it. */
1028 	ct->chip.irq_mask = irq_gc_mask_set_bit;
1029 	ct->chip.irq_unmask = irq_gc_mask_clr_bit;
1030 	ct->chip.irq_set_type = gpio_irq_type;
1031 
1032 	if (bank->regs->wkup_en)
1033 		ct->chip.irq_set_wake = gpio_wake_enable,
1034 
1035 	ct->regs.mask = OMAP_MPUIO_GPIO_INT / bank->stride;
1036 	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
1037 			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
1038 }
1039 
1040 static void omap_gpio_chip_init(struct gpio_bank *bank)
1041 {
1042 	int j;
1043 	static int gpio;
1044 
1045 	/*
1046 	 * REVISIT eventually switch from OMAP-specific gpio structs
1047 	 * over to the generic ones
1048 	 */
1049 	bank->chip.request = omap_gpio_request;
1050 	bank->chip.free = omap_gpio_free;
1051 	bank->chip.direction_input = gpio_input;
1052 	bank->chip.get = gpio_get;
1053 	bank->chip.direction_output = gpio_output;
1054 	bank->chip.set_debounce = gpio_debounce;
1055 	bank->chip.set = gpio_set;
1056 	bank->chip.to_irq = omap_gpio_to_irq;
1057 	if (bank->is_mpuio) {
1058 		bank->chip.label = "mpuio";
1059 		if (bank->regs->wkup_en)
1060 			bank->chip.dev = &omap_mpuio_device.dev;
1061 		bank->chip.base = OMAP_MPUIO(0);
1062 	} else {
1063 		bank->chip.label = "gpio";
1064 		bank->chip.base = gpio;
1065 		gpio += bank->width;
1066 	}
1067 	bank->chip.ngpio = bank->width;
1068 
1069 	gpiochip_add(&bank->chip);
1070 
1071 	for (j = 0; j < bank->width; j++) {
1072 		int irq = irq_create_mapping(bank->domain, j);
1073 		irq_set_lockdep_class(irq, &gpio_lock_class);
1074 		irq_set_chip_data(irq, bank);
1075 		if (bank->is_mpuio) {
1076 			omap_mpuio_alloc_gc(bank, irq, bank->width);
1077 		} else {
1078 			irq_set_chip_and_handler(irq, &gpio_irq_chip,
1079 						 handle_simple_irq);
1080 			set_irq_flags(irq, IRQF_VALID);
1081 		}
1082 	}
1083 	irq_set_chained_handler(bank->irq, gpio_irq_handler);
1084 	irq_set_handler_data(bank->irq, bank);
1085 }
1086 
1087 static const struct of_device_id omap_gpio_match[];
1088 
1089 static int omap_gpio_probe(struct platform_device *pdev)
1090 {
1091 	struct device *dev = &pdev->dev;
1092 	struct device_node *node = dev->of_node;
1093 	const struct of_device_id *match;
1094 	const struct omap_gpio_platform_data *pdata;
1095 	struct resource *res;
1096 	struct gpio_bank *bank;
1097 
1098 	match = of_match_device(of_match_ptr(omap_gpio_match), dev);
1099 
1100 	pdata = match ? match->data : dev->platform_data;
1101 	if (!pdata)
1102 		return -EINVAL;
1103 
1104 	bank = devm_kzalloc(dev, sizeof(struct gpio_bank), GFP_KERNEL);
1105 	if (!bank) {
1106 		dev_err(dev, "Memory alloc failed\n");
1107 		return -ENOMEM;
1108 	}
1109 
1110 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1111 	if (unlikely(!res)) {
1112 		dev_err(dev, "Invalid IRQ resource\n");
1113 		return -ENODEV;
1114 	}
1115 
1116 	bank->irq = res->start;
1117 	bank->dev = dev;
1118 	bank->dbck_flag = pdata->dbck_flag;
1119 	bank->stride = pdata->bank_stride;
1120 	bank->width = pdata->bank_width;
1121 	bank->is_mpuio = pdata->is_mpuio;
1122 	bank->non_wakeup_gpios = pdata->non_wakeup_gpios;
1123 	bank->regs = pdata->regs;
1124 #ifdef CONFIG_OF_GPIO
1125 	bank->chip.of_node = of_node_get(node);
1126 #endif
1127 	if (node) {
1128 		if (!of_property_read_bool(node, "ti,gpio-always-on"))
1129 			bank->loses_context = true;
1130 	} else {
1131 		bank->loses_context = pdata->loses_context;
1132 
1133 		if (bank->loses_context)
1134 			bank->get_context_loss_count =
1135 				pdata->get_context_loss_count;
1136 	}
1137 
1138 
1139 	bank->domain = irq_domain_add_linear(node, bank->width,
1140 					     &irq_domain_simple_ops, NULL);
1141 	if (!bank->domain)
1142 		return -ENODEV;
1143 
1144 	if (bank->regs->set_dataout && bank->regs->clr_dataout)
1145 		bank->set_dataout = _set_gpio_dataout_reg;
1146 	else
1147 		bank->set_dataout = _set_gpio_dataout_mask;
1148 
1149 	spin_lock_init(&bank->lock);
1150 
1151 	/* Static mapping, never released */
1152 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1153 	if (unlikely(!res)) {
1154 		dev_err(dev, "Invalid mem resource\n");
1155 		irq_domain_remove(bank->domain);
1156 		return -ENODEV;
1157 	}
1158 
1159 	if (!devm_request_mem_region(dev, res->start, resource_size(res),
1160 				     pdev->name)) {
1161 		dev_err(dev, "Region already claimed\n");
1162 		irq_domain_remove(bank->domain);
1163 		return -EBUSY;
1164 	}
1165 
1166 	bank->base = devm_ioremap(dev, res->start, resource_size(res));
1167 	if (!bank->base) {
1168 		dev_err(dev, "Could not ioremap\n");
1169 		irq_domain_remove(bank->domain);
1170 		return -ENOMEM;
1171 	}
1172 
1173 	platform_set_drvdata(pdev, bank);
1174 
1175 	pm_runtime_enable(bank->dev);
1176 	pm_runtime_irq_safe(bank->dev);
1177 	pm_runtime_get_sync(bank->dev);
1178 
1179 	if (bank->is_mpuio)
1180 		mpuio_init(bank);
1181 
1182 	omap_gpio_mod_init(bank);
1183 	omap_gpio_chip_init(bank);
1184 	omap_gpio_show_rev(bank);
1185 
1186 	pm_runtime_put(bank->dev);
1187 
1188 	list_add_tail(&bank->node, &omap_gpio_list);
1189 
1190 	return 0;
1191 }
1192 
1193 #ifdef CONFIG_ARCH_OMAP2PLUS
1194 
1195 #if defined(CONFIG_PM_RUNTIME)
1196 static void omap_gpio_restore_context(struct gpio_bank *bank);
1197 
1198 static int omap_gpio_runtime_suspend(struct device *dev)
1199 {
1200 	struct platform_device *pdev = to_platform_device(dev);
1201 	struct gpio_bank *bank = platform_get_drvdata(pdev);
1202 	u32 l1 = 0, l2 = 0;
1203 	unsigned long flags;
1204 	u32 wake_low, wake_hi;
1205 
1206 	spin_lock_irqsave(&bank->lock, flags);
1207 
1208 	/*
1209 	 * Only edges can generate a wakeup event to the PRCM.
1210 	 *
1211 	 * Therefore, ensure any wake-up capable GPIOs have
1212 	 * edge-detection enabled before going idle to ensure a wakeup
1213 	 * to the PRCM is generated on a GPIO transition. (c.f. 34xx
1214 	 * NDA TRM 25.5.3.1)
1215 	 *
1216 	 * The normal values will be restored upon ->runtime_resume()
1217 	 * by writing back the values saved in bank->context.
1218 	 */
1219 	wake_low = bank->context.leveldetect0 & bank->context.wake_en;
1220 	if (wake_low)
1221 		__raw_writel(wake_low | bank->context.fallingdetect,
1222 			     bank->base + bank->regs->fallingdetect);
1223 	wake_hi = bank->context.leveldetect1 & bank->context.wake_en;
1224 	if (wake_hi)
1225 		__raw_writel(wake_hi | bank->context.risingdetect,
1226 			     bank->base + bank->regs->risingdetect);
1227 
1228 	if (!bank->enabled_non_wakeup_gpios)
1229 		goto update_gpio_context_count;
1230 
1231 	if (bank->power_mode != OFF_MODE) {
1232 		bank->power_mode = 0;
1233 		goto update_gpio_context_count;
1234 	}
1235 	/*
1236 	 * If going to OFF, remove triggering for all
1237 	 * non-wakeup GPIOs.  Otherwise spurious IRQs will be
1238 	 * generated.  See OMAP2420 Errata item 1.101.
1239 	 */
1240 	bank->saved_datain = __raw_readl(bank->base +
1241 						bank->regs->datain);
1242 	l1 = bank->context.fallingdetect;
1243 	l2 = bank->context.risingdetect;
1244 
1245 	l1 &= ~bank->enabled_non_wakeup_gpios;
1246 	l2 &= ~bank->enabled_non_wakeup_gpios;
1247 
1248 	__raw_writel(l1, bank->base + bank->regs->fallingdetect);
1249 	__raw_writel(l2, bank->base + bank->regs->risingdetect);
1250 
1251 	bank->workaround_enabled = true;
1252 
1253 update_gpio_context_count:
1254 	if (bank->get_context_loss_count)
1255 		bank->context_loss_count =
1256 				bank->get_context_loss_count(bank->dev);
1257 
1258 	_gpio_dbck_disable(bank);
1259 	spin_unlock_irqrestore(&bank->lock, flags);
1260 
1261 	return 0;
1262 }
1263 
1264 static void omap_gpio_init_context(struct gpio_bank *p);
1265 
1266 static int omap_gpio_runtime_resume(struct device *dev)
1267 {
1268 	struct platform_device *pdev = to_platform_device(dev);
1269 	struct gpio_bank *bank = platform_get_drvdata(pdev);
1270 	u32 l = 0, gen, gen0, gen1;
1271 	unsigned long flags;
1272 	int c;
1273 
1274 	spin_lock_irqsave(&bank->lock, flags);
1275 
1276 	/*
1277 	 * On the first resume during the probe, the context has not
1278 	 * been initialised and so initialise it now. Also initialise
1279 	 * the context loss count.
1280 	 */
1281 	if (bank->loses_context && !bank->context_valid) {
1282 		omap_gpio_init_context(bank);
1283 
1284 		if (bank->get_context_loss_count)
1285 			bank->context_loss_count =
1286 				bank->get_context_loss_count(bank->dev);
1287 	}
1288 
1289 	_gpio_dbck_enable(bank);
1290 
1291 	/*
1292 	 * In ->runtime_suspend(), level-triggered, wakeup-enabled
1293 	 * GPIOs were set to edge trigger also in order to be able to
1294 	 * generate a PRCM wakeup.  Here we restore the
1295 	 * pre-runtime_suspend() values for edge triggering.
1296 	 */
1297 	__raw_writel(bank->context.fallingdetect,
1298 		     bank->base + bank->regs->fallingdetect);
1299 	__raw_writel(bank->context.risingdetect,
1300 		     bank->base + bank->regs->risingdetect);
1301 
1302 	if (bank->loses_context) {
1303 		if (!bank->get_context_loss_count) {
1304 			omap_gpio_restore_context(bank);
1305 		} else {
1306 			c = bank->get_context_loss_count(bank->dev);
1307 			if (c != bank->context_loss_count) {
1308 				omap_gpio_restore_context(bank);
1309 			} else {
1310 				spin_unlock_irqrestore(&bank->lock, flags);
1311 				return 0;
1312 			}
1313 		}
1314 	}
1315 
1316 	if (!bank->workaround_enabled) {
1317 		spin_unlock_irqrestore(&bank->lock, flags);
1318 		return 0;
1319 	}
1320 
1321 	l = __raw_readl(bank->base + bank->regs->datain);
1322 
1323 	/*
1324 	 * Check if any of the non-wakeup interrupt GPIOs have changed
1325 	 * state.  If so, generate an IRQ by software.  This is
1326 	 * horribly racy, but it's the best we can do to work around
1327 	 * this silicon bug.
1328 	 */
1329 	l ^= bank->saved_datain;
1330 	l &= bank->enabled_non_wakeup_gpios;
1331 
1332 	/*
1333 	 * No need to generate IRQs for the rising edge for gpio IRQs
1334 	 * configured with falling edge only; and vice versa.
1335 	 */
1336 	gen0 = l & bank->context.fallingdetect;
1337 	gen0 &= bank->saved_datain;
1338 
1339 	gen1 = l & bank->context.risingdetect;
1340 	gen1 &= ~(bank->saved_datain);
1341 
1342 	/* FIXME: Consider GPIO IRQs with level detections properly! */
1343 	gen = l & (~(bank->context.fallingdetect) &
1344 					 ~(bank->context.risingdetect));
1345 	/* Consider all GPIO IRQs needed to be updated */
1346 	gen |= gen0 | gen1;
1347 
1348 	if (gen) {
1349 		u32 old0, old1;
1350 
1351 		old0 = __raw_readl(bank->base + bank->regs->leveldetect0);
1352 		old1 = __raw_readl(bank->base + bank->regs->leveldetect1);
1353 
1354 		if (!bank->regs->irqstatus_raw0) {
1355 			__raw_writel(old0 | gen, bank->base +
1356 						bank->regs->leveldetect0);
1357 			__raw_writel(old1 | gen, bank->base +
1358 						bank->regs->leveldetect1);
1359 		}
1360 
1361 		if (bank->regs->irqstatus_raw0) {
1362 			__raw_writel(old0 | l, bank->base +
1363 						bank->regs->leveldetect0);
1364 			__raw_writel(old1 | l, bank->base +
1365 						bank->regs->leveldetect1);
1366 		}
1367 		__raw_writel(old0, bank->base + bank->regs->leveldetect0);
1368 		__raw_writel(old1, bank->base + bank->regs->leveldetect1);
1369 	}
1370 
1371 	bank->workaround_enabled = false;
1372 	spin_unlock_irqrestore(&bank->lock, flags);
1373 
1374 	return 0;
1375 }
1376 #endif /* CONFIG_PM_RUNTIME */
1377 
1378 void omap2_gpio_prepare_for_idle(int pwr_mode)
1379 {
1380 	struct gpio_bank *bank;
1381 
1382 	list_for_each_entry(bank, &omap_gpio_list, node) {
1383 		if (!bank->mod_usage || !bank->loses_context)
1384 			continue;
1385 
1386 		bank->power_mode = pwr_mode;
1387 
1388 		pm_runtime_put_sync_suspend(bank->dev);
1389 	}
1390 }
1391 
1392 void omap2_gpio_resume_after_idle(void)
1393 {
1394 	struct gpio_bank *bank;
1395 
1396 	list_for_each_entry(bank, &omap_gpio_list, node) {
1397 		if (!bank->mod_usage || !bank->loses_context)
1398 			continue;
1399 
1400 		pm_runtime_get_sync(bank->dev);
1401 	}
1402 }
1403 
1404 #if defined(CONFIG_PM_RUNTIME)
1405 static void omap_gpio_init_context(struct gpio_bank *p)
1406 {
1407 	struct omap_gpio_reg_offs *regs = p->regs;
1408 	void __iomem *base = p->base;
1409 
1410 	p->context.ctrl		= __raw_readl(base + regs->ctrl);
1411 	p->context.oe		= __raw_readl(base + regs->direction);
1412 	p->context.wake_en	= __raw_readl(base + regs->wkup_en);
1413 	p->context.leveldetect0	= __raw_readl(base + regs->leveldetect0);
1414 	p->context.leveldetect1	= __raw_readl(base + regs->leveldetect1);
1415 	p->context.risingdetect	= __raw_readl(base + regs->risingdetect);
1416 	p->context.fallingdetect = __raw_readl(base + regs->fallingdetect);
1417 	p->context.irqenable1	= __raw_readl(base + regs->irqenable);
1418 	p->context.irqenable2	= __raw_readl(base + regs->irqenable2);
1419 
1420 	if (regs->set_dataout && p->regs->clr_dataout)
1421 		p->context.dataout = __raw_readl(base + regs->set_dataout);
1422 	else
1423 		p->context.dataout = __raw_readl(base + regs->dataout);
1424 
1425 	p->context_valid = true;
1426 }
1427 
1428 static void omap_gpio_restore_context(struct gpio_bank *bank)
1429 {
1430 	__raw_writel(bank->context.wake_en,
1431 				bank->base + bank->regs->wkup_en);
1432 	__raw_writel(bank->context.ctrl, bank->base + bank->regs->ctrl);
1433 	__raw_writel(bank->context.leveldetect0,
1434 				bank->base + bank->regs->leveldetect0);
1435 	__raw_writel(bank->context.leveldetect1,
1436 				bank->base + bank->regs->leveldetect1);
1437 	__raw_writel(bank->context.risingdetect,
1438 				bank->base + bank->regs->risingdetect);
1439 	__raw_writel(bank->context.fallingdetect,
1440 				bank->base + bank->regs->fallingdetect);
1441 	if (bank->regs->set_dataout && bank->regs->clr_dataout)
1442 		__raw_writel(bank->context.dataout,
1443 				bank->base + bank->regs->set_dataout);
1444 	else
1445 		__raw_writel(bank->context.dataout,
1446 				bank->base + bank->regs->dataout);
1447 	__raw_writel(bank->context.oe, bank->base + bank->regs->direction);
1448 
1449 	if (bank->dbck_enable_mask) {
1450 		__raw_writel(bank->context.debounce, bank->base +
1451 					bank->regs->debounce);
1452 		__raw_writel(bank->context.debounce_en,
1453 					bank->base + bank->regs->debounce_en);
1454 	}
1455 
1456 	__raw_writel(bank->context.irqenable1,
1457 				bank->base + bank->regs->irqenable);
1458 	__raw_writel(bank->context.irqenable2,
1459 				bank->base + bank->regs->irqenable2);
1460 }
1461 #endif /* CONFIG_PM_RUNTIME */
1462 #else
1463 #define omap_gpio_runtime_suspend NULL
1464 #define omap_gpio_runtime_resume NULL
1465 static void omap_gpio_init_context(struct gpio_bank *p) {}
1466 #endif
1467 
1468 static const struct dev_pm_ops gpio_pm_ops = {
1469 	SET_RUNTIME_PM_OPS(omap_gpio_runtime_suspend, omap_gpio_runtime_resume,
1470 									NULL)
1471 };
1472 
1473 #if defined(CONFIG_OF)
1474 static struct omap_gpio_reg_offs omap2_gpio_regs = {
1475 	.revision =		OMAP24XX_GPIO_REVISION,
1476 	.direction =		OMAP24XX_GPIO_OE,
1477 	.datain =		OMAP24XX_GPIO_DATAIN,
1478 	.dataout =		OMAP24XX_GPIO_DATAOUT,
1479 	.set_dataout =		OMAP24XX_GPIO_SETDATAOUT,
1480 	.clr_dataout =		OMAP24XX_GPIO_CLEARDATAOUT,
1481 	.irqstatus =		OMAP24XX_GPIO_IRQSTATUS1,
1482 	.irqstatus2 =		OMAP24XX_GPIO_IRQSTATUS2,
1483 	.irqenable =		OMAP24XX_GPIO_IRQENABLE1,
1484 	.irqenable2 =		OMAP24XX_GPIO_IRQENABLE2,
1485 	.set_irqenable =	OMAP24XX_GPIO_SETIRQENABLE1,
1486 	.clr_irqenable =	OMAP24XX_GPIO_CLEARIRQENABLE1,
1487 	.debounce =		OMAP24XX_GPIO_DEBOUNCE_VAL,
1488 	.debounce_en =		OMAP24XX_GPIO_DEBOUNCE_EN,
1489 	.ctrl =			OMAP24XX_GPIO_CTRL,
1490 	.wkup_en =		OMAP24XX_GPIO_WAKE_EN,
1491 	.leveldetect0 =		OMAP24XX_GPIO_LEVELDETECT0,
1492 	.leveldetect1 =		OMAP24XX_GPIO_LEVELDETECT1,
1493 	.risingdetect =		OMAP24XX_GPIO_RISINGDETECT,
1494 	.fallingdetect =	OMAP24XX_GPIO_FALLINGDETECT,
1495 };
1496 
1497 static struct omap_gpio_reg_offs omap4_gpio_regs = {
1498 	.revision =		OMAP4_GPIO_REVISION,
1499 	.direction =		OMAP4_GPIO_OE,
1500 	.datain =		OMAP4_GPIO_DATAIN,
1501 	.dataout =		OMAP4_GPIO_DATAOUT,
1502 	.set_dataout =		OMAP4_GPIO_SETDATAOUT,
1503 	.clr_dataout =		OMAP4_GPIO_CLEARDATAOUT,
1504 	.irqstatus =		OMAP4_GPIO_IRQSTATUS0,
1505 	.irqstatus2 =		OMAP4_GPIO_IRQSTATUS1,
1506 	.irqenable =		OMAP4_GPIO_IRQSTATUSSET0,
1507 	.irqenable2 =		OMAP4_GPIO_IRQSTATUSSET1,
1508 	.set_irqenable =	OMAP4_GPIO_IRQSTATUSSET0,
1509 	.clr_irqenable =	OMAP4_GPIO_IRQSTATUSCLR0,
1510 	.debounce =		OMAP4_GPIO_DEBOUNCINGTIME,
1511 	.debounce_en =		OMAP4_GPIO_DEBOUNCENABLE,
1512 	.ctrl =			OMAP4_GPIO_CTRL,
1513 	.wkup_en =		OMAP4_GPIO_IRQWAKEN0,
1514 	.leveldetect0 =		OMAP4_GPIO_LEVELDETECT0,
1515 	.leveldetect1 =		OMAP4_GPIO_LEVELDETECT1,
1516 	.risingdetect =		OMAP4_GPIO_RISINGDETECT,
1517 	.fallingdetect =	OMAP4_GPIO_FALLINGDETECT,
1518 };
1519 
1520 static const struct omap_gpio_platform_data omap2_pdata = {
1521 	.regs = &omap2_gpio_regs,
1522 	.bank_width = 32,
1523 	.dbck_flag = false,
1524 };
1525 
1526 static const struct omap_gpio_platform_data omap3_pdata = {
1527 	.regs = &omap2_gpio_regs,
1528 	.bank_width = 32,
1529 	.dbck_flag = true,
1530 };
1531 
1532 static const struct omap_gpio_platform_data omap4_pdata = {
1533 	.regs = &omap4_gpio_regs,
1534 	.bank_width = 32,
1535 	.dbck_flag = true,
1536 };
1537 
1538 static const struct of_device_id omap_gpio_match[] = {
1539 	{
1540 		.compatible = "ti,omap4-gpio",
1541 		.data = &omap4_pdata,
1542 	},
1543 	{
1544 		.compatible = "ti,omap3-gpio",
1545 		.data = &omap3_pdata,
1546 	},
1547 	{
1548 		.compatible = "ti,omap2-gpio",
1549 		.data = &omap2_pdata,
1550 	},
1551 	{ },
1552 };
1553 MODULE_DEVICE_TABLE(of, omap_gpio_match);
1554 #endif
1555 
1556 static struct platform_driver omap_gpio_driver = {
1557 	.probe		= omap_gpio_probe,
1558 	.driver		= {
1559 		.name	= "omap_gpio",
1560 		.pm	= &gpio_pm_ops,
1561 		.of_match_table = of_match_ptr(omap_gpio_match),
1562 	},
1563 };
1564 
1565 /*
1566  * gpio driver register needs to be done before
1567  * machine_init functions access gpio APIs.
1568  * Hence omap_gpio_drv_reg() is a postcore_initcall.
1569  */
1570 static int __init omap_gpio_drv_reg(void)
1571 {
1572 	return platform_driver_register(&omap_gpio_driver);
1573 }
1574 postcore_initcall(omap_gpio_drv_reg);
1575