xref: /openbmc/linux/drivers/gpio/gpio-omap.c (revision 12eb4683) 
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 irq_usage;
67 	u32 dbck_enable_mask;
68 	bool dbck_enabled;
69 	struct device *dev;
70 	bool is_mpuio;
71 	bool dbck_flag;
72 	bool loses_context;
73 	bool context_valid;
74 	int stride;
75 	u32 width;
76 	int context_loss_count;
77 	int power_mode;
78 	bool workaround_enabled;
79 
80 	void (*set_dataout)(struct gpio_bank *bank, int gpio, int enable);
81 	int (*get_context_loss_count)(struct device *dev);
82 
83 	struct omap_gpio_reg_offs *regs;
84 };
85 
86 #define GPIO_INDEX(bank, gpio) (gpio % bank->width)
87 #define GPIO_BIT(bank, gpio) (1 << GPIO_INDEX(bank, gpio))
88 #define GPIO_MOD_CTRL_BIT	BIT(0)
89 
90 #define BANK_USED(bank) (bank->mod_usage || bank->irq_usage)
91 #define LINE_USED(line, offset) (line & (1 << offset))
92 
93 static int irq_to_gpio(struct gpio_bank *bank, unsigned int gpio_irq)
94 {
95 	return bank->chip.base + gpio_irq;
96 }
97 
98 static int omap_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
99 {
100 	struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
101 
102 	return irq_find_mapping(bank->domain, offset);
103 }
104 
105 static void _set_gpio_direction(struct gpio_bank *bank, int gpio, int is_input)
106 {
107 	void __iomem *reg = bank->base;
108 	u32 l;
109 
110 	reg += bank->regs->direction;
111 	l = __raw_readl(reg);
112 	if (is_input)
113 		l |= 1 << gpio;
114 	else
115 		l &= ~(1 << gpio);
116 	__raw_writel(l, reg);
117 	bank->context.oe = l;
118 }
119 
120 
121 /* set data out value using dedicate set/clear register */
122 static void _set_gpio_dataout_reg(struct gpio_bank *bank, int gpio, int enable)
123 {
124 	void __iomem *reg = bank->base;
125 	u32 l = GPIO_BIT(bank, gpio);
126 
127 	if (enable) {
128 		reg += bank->regs->set_dataout;
129 		bank->context.dataout |= l;
130 	} else {
131 		reg += bank->regs->clr_dataout;
132 		bank->context.dataout &= ~l;
133 	}
134 
135 	__raw_writel(l, reg);
136 }
137 
138 /* set data out value using mask register */
139 static void _set_gpio_dataout_mask(struct gpio_bank *bank, int gpio, int enable)
140 {
141 	void __iomem *reg = bank->base + bank->regs->dataout;
142 	u32 gpio_bit = GPIO_BIT(bank, gpio);
143 	u32 l;
144 
145 	l = __raw_readl(reg);
146 	if (enable)
147 		l |= gpio_bit;
148 	else
149 		l &= ~gpio_bit;
150 	__raw_writel(l, reg);
151 	bank->context.dataout = l;
152 }
153 
154 static int _get_gpio_datain(struct gpio_bank *bank, int offset)
155 {
156 	void __iomem *reg = bank->base + bank->regs->datain;
157 
158 	return (__raw_readl(reg) & (1 << offset)) != 0;
159 }
160 
161 static int _get_gpio_dataout(struct gpio_bank *bank, int offset)
162 {
163 	void __iomem *reg = bank->base + bank->regs->dataout;
164 
165 	return (__raw_readl(reg) & (1 << offset)) != 0;
166 }
167 
168 static inline void _gpio_rmw(void __iomem *base, u32 reg, u32 mask, bool set)
169 {
170 	int l = __raw_readl(base + reg);
171 
172 	if (set)
173 		l |= mask;
174 	else
175 		l &= ~mask;
176 
177 	__raw_writel(l, base + reg);
178 }
179 
180 static inline void _gpio_dbck_enable(struct gpio_bank *bank)
181 {
182 	if (bank->dbck_enable_mask && !bank->dbck_enabled) {
183 		clk_enable(bank->dbck);
184 		bank->dbck_enabled = true;
185 
186 		__raw_writel(bank->dbck_enable_mask,
187 			     bank->base + bank->regs->debounce_en);
188 	}
189 }
190 
191 static inline void _gpio_dbck_disable(struct gpio_bank *bank)
192 {
193 	if (bank->dbck_enable_mask && bank->dbck_enabled) {
194 		/*
195 		 * Disable debounce before cutting it's clock. If debounce is
196 		 * enabled but the clock is not, GPIO module seems to be unable
197 		 * to detect events and generate interrupts at least on OMAP3.
198 		 */
199 		__raw_writel(0, bank->base + bank->regs->debounce_en);
200 
201 		clk_disable(bank->dbck);
202 		bank->dbck_enabled = false;
203 	}
204 }
205 
206 /**
207  * _set_gpio_debounce - low level gpio debounce time
208  * @bank: the gpio bank we're acting upon
209  * @gpio: the gpio number on this @gpio
210  * @debounce: debounce time to use
211  *
212  * OMAP's debounce time is in 31us steps so we need
213  * to convert and round up to the closest unit.
214  */
215 static void _set_gpio_debounce(struct gpio_bank *bank, unsigned gpio,
216 		unsigned debounce)
217 {
218 	void __iomem		*reg;
219 	u32			val;
220 	u32			l;
221 
222 	if (!bank->dbck_flag)
223 		return;
224 
225 	if (debounce < 32)
226 		debounce = 0x01;
227 	else if (debounce > 7936)
228 		debounce = 0xff;
229 	else
230 		debounce = (debounce / 0x1f) - 1;
231 
232 	l = GPIO_BIT(bank, gpio);
233 
234 	clk_enable(bank->dbck);
235 	reg = bank->base + bank->regs->debounce;
236 	__raw_writel(debounce, reg);
237 
238 	reg = bank->base + bank->regs->debounce_en;
239 	val = __raw_readl(reg);
240 
241 	if (debounce)
242 		val |= l;
243 	else
244 		val &= ~l;
245 	bank->dbck_enable_mask = val;
246 
247 	__raw_writel(val, reg);
248 	clk_disable(bank->dbck);
249 	/*
250 	 * Enable debounce clock per module.
251 	 * This call is mandatory because in omap_gpio_request() when
252 	 * *_runtime_get_sync() is called,  _gpio_dbck_enable() within
253 	 * runtime callbck fails to turn on dbck because dbck_enable_mask
254 	 * used within _gpio_dbck_enable() is still not initialized at
255 	 * that point. Therefore we have to enable dbck here.
256 	 */
257 	_gpio_dbck_enable(bank);
258 	if (bank->dbck_enable_mask) {
259 		bank->context.debounce = debounce;
260 		bank->context.debounce_en = val;
261 	}
262 }
263 
264 /**
265  * _clear_gpio_debounce - clear debounce settings for a gpio
266  * @bank: the gpio bank we're acting upon
267  * @gpio: the gpio number on this @gpio
268  *
269  * If a gpio is using debounce, then clear the debounce enable bit and if
270  * this is the only gpio in this bank using debounce, then clear the debounce
271  * time too. The debounce clock will also be disabled when calling this function
272  * if this is the only gpio in the bank using debounce.
273  */
274 static void _clear_gpio_debounce(struct gpio_bank *bank, unsigned gpio)
275 {
276 	u32 gpio_bit = GPIO_BIT(bank, gpio);
277 
278 	if (!bank->dbck_flag)
279 		return;
280 
281 	if (!(bank->dbck_enable_mask & gpio_bit))
282 		return;
283 
284 	bank->dbck_enable_mask &= ~gpio_bit;
285 	bank->context.debounce_en &= ~gpio_bit;
286 	__raw_writel(bank->context.debounce_en,
287 		     bank->base + bank->regs->debounce_en);
288 
289 	if (!bank->dbck_enable_mask) {
290 		bank->context.debounce = 0;
291 		__raw_writel(bank->context.debounce, bank->base +
292 			     bank->regs->debounce);
293 		clk_disable(bank->dbck);
294 		bank->dbck_enabled = false;
295 	}
296 }
297 
298 static inline void set_gpio_trigger(struct gpio_bank *bank, int gpio,
299 						unsigned trigger)
300 {
301 	void __iomem *base = bank->base;
302 	u32 gpio_bit = 1 << gpio;
303 
304 	_gpio_rmw(base, bank->regs->leveldetect0, gpio_bit,
305 		  trigger & IRQ_TYPE_LEVEL_LOW);
306 	_gpio_rmw(base, bank->regs->leveldetect1, gpio_bit,
307 		  trigger & IRQ_TYPE_LEVEL_HIGH);
308 	_gpio_rmw(base, bank->regs->risingdetect, gpio_bit,
309 		  trigger & IRQ_TYPE_EDGE_RISING);
310 	_gpio_rmw(base, bank->regs->fallingdetect, gpio_bit,
311 		  trigger & IRQ_TYPE_EDGE_FALLING);
312 
313 	bank->context.leveldetect0 =
314 			__raw_readl(bank->base + bank->regs->leveldetect0);
315 	bank->context.leveldetect1 =
316 			__raw_readl(bank->base + bank->regs->leveldetect1);
317 	bank->context.risingdetect =
318 			__raw_readl(bank->base + bank->regs->risingdetect);
319 	bank->context.fallingdetect =
320 			__raw_readl(bank->base + bank->regs->fallingdetect);
321 
322 	if (likely(!(bank->non_wakeup_gpios & gpio_bit))) {
323 		_gpio_rmw(base, bank->regs->wkup_en, gpio_bit, trigger != 0);
324 		bank->context.wake_en =
325 			__raw_readl(bank->base + bank->regs->wkup_en);
326 	}
327 
328 	/* This part needs to be executed always for OMAP{34xx, 44xx} */
329 	if (!bank->regs->irqctrl) {
330 		/* On omap24xx proceed only when valid GPIO bit is set */
331 		if (bank->non_wakeup_gpios) {
332 			if (!(bank->non_wakeup_gpios & gpio_bit))
333 				goto exit;
334 		}
335 
336 		/*
337 		 * Log the edge gpio and manually trigger the IRQ
338 		 * after resume if the input level changes
339 		 * to avoid irq lost during PER RET/OFF mode
340 		 * Applies for omap2 non-wakeup gpio and all omap3 gpios
341 		 */
342 		if (trigger & IRQ_TYPE_EDGE_BOTH)
343 			bank->enabled_non_wakeup_gpios |= gpio_bit;
344 		else
345 			bank->enabled_non_wakeup_gpios &= ~gpio_bit;
346 	}
347 
348 exit:
349 	bank->level_mask =
350 		__raw_readl(bank->base + bank->regs->leveldetect0) |
351 		__raw_readl(bank->base + bank->regs->leveldetect1);
352 }
353 
354 #ifdef CONFIG_ARCH_OMAP1
355 /*
356  * This only applies to chips that can't do both rising and falling edge
357  * detection at once.  For all other chips, this function is a noop.
358  */
359 static void _toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio)
360 {
361 	void __iomem *reg = bank->base;
362 	u32 l = 0;
363 
364 	if (!bank->regs->irqctrl)
365 		return;
366 
367 	reg += bank->regs->irqctrl;
368 
369 	l = __raw_readl(reg);
370 	if ((l >> gpio) & 1)
371 		l &= ~(1 << gpio);
372 	else
373 		l |= 1 << gpio;
374 
375 	__raw_writel(l, reg);
376 }
377 #else
378 static void _toggle_gpio_edge_triggering(struct gpio_bank *bank, int gpio) {}
379 #endif
380 
381 static int _set_gpio_triggering(struct gpio_bank *bank, int gpio,
382 							unsigned trigger)
383 {
384 	void __iomem *reg = bank->base;
385 	void __iomem *base = bank->base;
386 	u32 l = 0;
387 
388 	if (bank->regs->leveldetect0 && bank->regs->wkup_en) {
389 		set_gpio_trigger(bank, gpio, trigger);
390 	} else if (bank->regs->irqctrl) {
391 		reg += bank->regs->irqctrl;
392 
393 		l = __raw_readl(reg);
394 		if ((trigger & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
395 			bank->toggle_mask |= 1 << gpio;
396 		if (trigger & IRQ_TYPE_EDGE_RISING)
397 			l |= 1 << gpio;
398 		else if (trigger & IRQ_TYPE_EDGE_FALLING)
399 			l &= ~(1 << gpio);
400 		else
401 			return -EINVAL;
402 
403 		__raw_writel(l, reg);
404 	} else if (bank->regs->edgectrl1) {
405 		if (gpio & 0x08)
406 			reg += bank->regs->edgectrl2;
407 		else
408 			reg += bank->regs->edgectrl1;
409 
410 		gpio &= 0x07;
411 		l = __raw_readl(reg);
412 		l &= ~(3 << (gpio << 1));
413 		if (trigger & IRQ_TYPE_EDGE_RISING)
414 			l |= 2 << (gpio << 1);
415 		if (trigger & IRQ_TYPE_EDGE_FALLING)
416 			l |= 1 << (gpio << 1);
417 
418 		/* Enable wake-up during idle for dynamic tick */
419 		_gpio_rmw(base, bank->regs->wkup_en, 1 << gpio, trigger);
420 		bank->context.wake_en =
421 			__raw_readl(bank->base + bank->regs->wkup_en);
422 		__raw_writel(l, reg);
423 	}
424 	return 0;
425 }
426 
427 static void _enable_gpio_module(struct gpio_bank *bank, unsigned offset)
428 {
429 	if (bank->regs->pinctrl) {
430 		void __iomem *reg = bank->base + bank->regs->pinctrl;
431 
432 		/* Claim the pin for MPU */
433 		__raw_writel(__raw_readl(reg) | (1 << offset), reg);
434 	}
435 
436 	if (bank->regs->ctrl && !BANK_USED(bank)) {
437 		void __iomem *reg = bank->base + bank->regs->ctrl;
438 		u32 ctrl;
439 
440 		ctrl = __raw_readl(reg);
441 		/* Module is enabled, clocks are not gated */
442 		ctrl &= ~GPIO_MOD_CTRL_BIT;
443 		__raw_writel(ctrl, reg);
444 		bank->context.ctrl = ctrl;
445 	}
446 }
447 
448 static void _disable_gpio_module(struct gpio_bank *bank, unsigned offset)
449 {
450 	void __iomem *base = bank->base;
451 
452 	if (bank->regs->wkup_en &&
453 	    !LINE_USED(bank->mod_usage, offset) &&
454 	    !LINE_USED(bank->irq_usage, offset)) {
455 		/* Disable wake-up during idle for dynamic tick */
456 		_gpio_rmw(base, bank->regs->wkup_en, 1 << offset, 0);
457 		bank->context.wake_en =
458 			__raw_readl(bank->base + bank->regs->wkup_en);
459 	}
460 
461 	if (bank->regs->ctrl && !BANK_USED(bank)) {
462 		void __iomem *reg = bank->base + bank->regs->ctrl;
463 		u32 ctrl;
464 
465 		ctrl = __raw_readl(reg);
466 		/* Module is disabled, clocks are gated */
467 		ctrl |= GPIO_MOD_CTRL_BIT;
468 		__raw_writel(ctrl, reg);
469 		bank->context.ctrl = ctrl;
470 	}
471 }
472 
473 static int gpio_is_input(struct gpio_bank *bank, int mask)
474 {
475 	void __iomem *reg = bank->base + bank->regs->direction;
476 
477 	return __raw_readl(reg) & mask;
478 }
479 
480 static int gpio_irq_type(struct irq_data *d, unsigned type)
481 {
482 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
483 	unsigned gpio = 0;
484 	int retval;
485 	unsigned long flags;
486 	unsigned offset;
487 
488 	if (!BANK_USED(bank))
489 		pm_runtime_get_sync(bank->dev);
490 
491 #ifdef CONFIG_ARCH_OMAP1
492 	if (d->irq > IH_MPUIO_BASE)
493 		gpio = OMAP_MPUIO(d->irq - IH_MPUIO_BASE);
494 #endif
495 
496 	if (!gpio)
497 		gpio = irq_to_gpio(bank, d->hwirq);
498 
499 	if (type & ~IRQ_TYPE_SENSE_MASK)
500 		return -EINVAL;
501 
502 	if (!bank->regs->leveldetect0 &&
503 		(type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH)))
504 		return -EINVAL;
505 
506 	spin_lock_irqsave(&bank->lock, flags);
507 	offset = GPIO_INDEX(bank, gpio);
508 	retval = _set_gpio_triggering(bank, offset, type);
509 	if (!LINE_USED(bank->mod_usage, offset)) {
510 		_enable_gpio_module(bank, offset);
511 		_set_gpio_direction(bank, offset, 1);
512 	} else if (!gpio_is_input(bank, 1 << offset)) {
513 		spin_unlock_irqrestore(&bank->lock, flags);
514 		return -EINVAL;
515 	}
516 
517 	retval = gpio_lock_as_irq(&bank->chip, offset);
518 	if (retval) {
519 		dev_err(bank->dev, "unable to lock offset %d for IRQ\n",
520 			offset);
521 		spin_unlock_irqrestore(&bank->lock, flags);
522 		return retval;
523 	}
524 
525 	bank->irq_usage |= 1 << GPIO_INDEX(bank, gpio);
526 	spin_unlock_irqrestore(&bank->lock, flags);
527 
528 	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
529 		__irq_set_handler_locked(d->irq, handle_level_irq);
530 	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
531 		__irq_set_handler_locked(d->irq, handle_edge_irq);
532 
533 	return retval;
534 }
535 
536 static void _clear_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
537 {
538 	void __iomem *reg = bank->base;
539 
540 	reg += bank->regs->irqstatus;
541 	__raw_writel(gpio_mask, reg);
542 
543 	/* Workaround for clearing DSP GPIO interrupts to allow retention */
544 	if (bank->regs->irqstatus2) {
545 		reg = bank->base + bank->regs->irqstatus2;
546 		__raw_writel(gpio_mask, reg);
547 	}
548 
549 	/* Flush posted write for the irq status to avoid spurious interrupts */
550 	__raw_readl(reg);
551 }
552 
553 static inline void _clear_gpio_irqstatus(struct gpio_bank *bank, int gpio)
554 {
555 	_clear_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
556 }
557 
558 static u32 _get_gpio_irqbank_mask(struct gpio_bank *bank)
559 {
560 	void __iomem *reg = bank->base;
561 	u32 l;
562 	u32 mask = (1 << bank->width) - 1;
563 
564 	reg += bank->regs->irqenable;
565 	l = __raw_readl(reg);
566 	if (bank->regs->irqenable_inv)
567 		l = ~l;
568 	l &= mask;
569 	return l;
570 }
571 
572 static void _enable_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
573 {
574 	void __iomem *reg = bank->base;
575 	u32 l;
576 
577 	if (bank->regs->set_irqenable) {
578 		reg += bank->regs->set_irqenable;
579 		l = gpio_mask;
580 		bank->context.irqenable1 |= gpio_mask;
581 	} else {
582 		reg += bank->regs->irqenable;
583 		l = __raw_readl(reg);
584 		if (bank->regs->irqenable_inv)
585 			l &= ~gpio_mask;
586 		else
587 			l |= gpio_mask;
588 		bank->context.irqenable1 = l;
589 	}
590 
591 	__raw_writel(l, reg);
592 }
593 
594 static void _disable_gpio_irqbank(struct gpio_bank *bank, int gpio_mask)
595 {
596 	void __iomem *reg = bank->base;
597 	u32 l;
598 
599 	if (bank->regs->clr_irqenable) {
600 		reg += bank->regs->clr_irqenable;
601 		l = gpio_mask;
602 		bank->context.irqenable1 &= ~gpio_mask;
603 	} else {
604 		reg += bank->regs->irqenable;
605 		l = __raw_readl(reg);
606 		if (bank->regs->irqenable_inv)
607 			l |= gpio_mask;
608 		else
609 			l &= ~gpio_mask;
610 		bank->context.irqenable1 = l;
611 	}
612 
613 	__raw_writel(l, reg);
614 }
615 
616 static inline void _set_gpio_irqenable(struct gpio_bank *bank, int gpio, int enable)
617 {
618 	if (enable)
619 		_enable_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
620 	else
621 		_disable_gpio_irqbank(bank, GPIO_BIT(bank, gpio));
622 }
623 
624 /*
625  * Note that ENAWAKEUP needs to be enabled in GPIO_SYSCONFIG register.
626  * 1510 does not seem to have a wake-up register. If JTAG is connected
627  * to the target, system will wake up always on GPIO events. While
628  * system is running all registered GPIO interrupts need to have wake-up
629  * enabled. When system is suspended, only selected GPIO interrupts need
630  * to have wake-up enabled.
631  */
632 static int _set_gpio_wakeup(struct gpio_bank *bank, int gpio, int enable)
633 {
634 	u32 gpio_bit = GPIO_BIT(bank, gpio);
635 	unsigned long flags;
636 
637 	if (bank->non_wakeup_gpios & gpio_bit) {
638 		dev_err(bank->dev,
639 			"Unable to modify wakeup on non-wakeup GPIO%d\n", gpio);
640 		return -EINVAL;
641 	}
642 
643 	spin_lock_irqsave(&bank->lock, flags);
644 	if (enable)
645 		bank->context.wake_en |= gpio_bit;
646 	else
647 		bank->context.wake_en &= ~gpio_bit;
648 
649 	__raw_writel(bank->context.wake_en, bank->base + bank->regs->wkup_en);
650 	spin_unlock_irqrestore(&bank->lock, flags);
651 
652 	return 0;
653 }
654 
655 static void _reset_gpio(struct gpio_bank *bank, int gpio)
656 {
657 	_set_gpio_direction(bank, GPIO_INDEX(bank, gpio), 1);
658 	_set_gpio_irqenable(bank, gpio, 0);
659 	_clear_gpio_irqstatus(bank, gpio);
660 	_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE);
661 	_clear_gpio_debounce(bank, gpio);
662 }
663 
664 /* Use disable_irq_wake() and enable_irq_wake() functions from drivers */
665 static int gpio_wake_enable(struct irq_data *d, unsigned int enable)
666 {
667 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
668 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
669 
670 	return _set_gpio_wakeup(bank, gpio, enable);
671 }
672 
673 static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
674 {
675 	struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
676 	unsigned long flags;
677 
678 	/*
679 	 * If this is the first gpio_request for the bank,
680 	 * enable the bank module.
681 	 */
682 	if (!BANK_USED(bank))
683 		pm_runtime_get_sync(bank->dev);
684 
685 	spin_lock_irqsave(&bank->lock, flags);
686 	/* Set trigger to none. You need to enable the desired trigger with
687 	 * request_irq() or set_irq_type(). Only do this if the IRQ line has
688 	 * not already been requested.
689 	 */
690 	if (!LINE_USED(bank->irq_usage, offset)) {
691 		_set_gpio_triggering(bank, offset, IRQ_TYPE_NONE);
692 		_enable_gpio_module(bank, offset);
693 	}
694 	bank->mod_usage |= 1 << offset;
695 	spin_unlock_irqrestore(&bank->lock, flags);
696 
697 	return 0;
698 }
699 
700 static void omap_gpio_free(struct gpio_chip *chip, unsigned offset)
701 {
702 	struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
703 	unsigned long flags;
704 
705 	spin_lock_irqsave(&bank->lock, flags);
706 	bank->mod_usage &= ~(1 << offset);
707 	_disable_gpio_module(bank, offset);
708 	_reset_gpio(bank, bank->chip.base + offset);
709 	spin_unlock_irqrestore(&bank->lock, flags);
710 
711 	/*
712 	 * If this is the last gpio to be freed in the bank,
713 	 * disable the bank module.
714 	 */
715 	if (!BANK_USED(bank))
716 		pm_runtime_put(bank->dev);
717 }
718 
719 /*
720  * We need to unmask the GPIO bank interrupt as soon as possible to
721  * avoid missing GPIO interrupts for other lines in the bank.
722  * Then we need to mask-read-clear-unmask the triggered GPIO lines
723  * in the bank to avoid missing nested interrupts for a GPIO line.
724  * If we wait to unmask individual GPIO lines in the bank after the
725  * line's interrupt handler has been run, we may miss some nested
726  * interrupts.
727  */
728 static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
729 {
730 	void __iomem *isr_reg = NULL;
731 	u32 isr;
732 	unsigned int bit;
733 	struct gpio_bank *bank;
734 	int unmasked = 0;
735 	struct irq_chip *chip = irq_desc_get_chip(desc);
736 
737 	chained_irq_enter(chip, desc);
738 
739 	bank = irq_get_handler_data(irq);
740 	isr_reg = bank->base + bank->regs->irqstatus;
741 	pm_runtime_get_sync(bank->dev);
742 
743 	if (WARN_ON(!isr_reg))
744 		goto exit;
745 
746 	while (1) {
747 		u32 isr_saved, level_mask = 0;
748 		u32 enabled;
749 
750 		enabled = _get_gpio_irqbank_mask(bank);
751 		isr_saved = isr = __raw_readl(isr_reg) & enabled;
752 
753 		if (bank->level_mask)
754 			level_mask = bank->level_mask & enabled;
755 
756 		/* clear edge sensitive interrupts before handler(s) are
757 		called so that we don't miss any interrupt occurred while
758 		executing them */
759 		_disable_gpio_irqbank(bank, isr_saved & ~level_mask);
760 		_clear_gpio_irqbank(bank, isr_saved & ~level_mask);
761 		_enable_gpio_irqbank(bank, isr_saved & ~level_mask);
762 
763 		/* if there is only edge sensitive GPIO pin interrupts
764 		configured, we could unmask GPIO bank interrupt immediately */
765 		if (!level_mask && !unmasked) {
766 			unmasked = 1;
767 			chained_irq_exit(chip, desc);
768 		}
769 
770 		if (!isr)
771 			break;
772 
773 		while (isr) {
774 			bit = __ffs(isr);
775 			isr &= ~(1 << bit);
776 
777 			/*
778 			 * Some chips can't respond to both rising and falling
779 			 * at the same time.  If this irq was requested with
780 			 * both flags, we need to flip the ICR data for the IRQ
781 			 * to respond to the IRQ for the opposite direction.
782 			 * This will be indicated in the bank toggle_mask.
783 			 */
784 			if (bank->toggle_mask & (1 << bit))
785 				_toggle_gpio_edge_triggering(bank, bit);
786 
787 			generic_handle_irq(irq_find_mapping(bank->domain, bit));
788 		}
789 	}
790 	/* if bank has any level sensitive GPIO pin interrupt
791 	configured, we must unmask the bank interrupt only after
792 	handler(s) are executed in order to avoid spurious bank
793 	interrupt */
794 exit:
795 	if (!unmasked)
796 		chained_irq_exit(chip, desc);
797 	pm_runtime_put(bank->dev);
798 }
799 
800 static void gpio_irq_shutdown(struct irq_data *d)
801 {
802 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
803 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
804 	unsigned long flags;
805 	unsigned offset = GPIO_INDEX(bank, gpio);
806 
807 	spin_lock_irqsave(&bank->lock, flags);
808 	gpio_unlock_as_irq(&bank->chip, offset);
809 	bank->irq_usage &= ~(1 << offset);
810 	_disable_gpio_module(bank, offset);
811 	_reset_gpio(bank, gpio);
812 	spin_unlock_irqrestore(&bank->lock, flags);
813 
814 	/*
815 	 * If this is the last IRQ to be freed in the bank,
816 	 * disable the bank module.
817 	 */
818 	if (!BANK_USED(bank))
819 		pm_runtime_put(bank->dev);
820 }
821 
822 static void gpio_ack_irq(struct irq_data *d)
823 {
824 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
825 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
826 
827 	_clear_gpio_irqstatus(bank, gpio);
828 }
829 
830 static void gpio_mask_irq(struct irq_data *d)
831 {
832 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
833 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
834 	unsigned long flags;
835 
836 	spin_lock_irqsave(&bank->lock, flags);
837 	_set_gpio_irqenable(bank, gpio, 0);
838 	_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE);
839 	spin_unlock_irqrestore(&bank->lock, flags);
840 }
841 
842 static void gpio_unmask_irq(struct irq_data *d)
843 {
844 	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
845 	unsigned int gpio = irq_to_gpio(bank, d->hwirq);
846 	unsigned int irq_mask = GPIO_BIT(bank, gpio);
847 	u32 trigger = irqd_get_trigger_type(d);
848 	unsigned long flags;
849 
850 	spin_lock_irqsave(&bank->lock, flags);
851 	if (trigger)
852 		_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), trigger);
853 
854 	/* For level-triggered GPIOs, the clearing must be done after
855 	 * the HW source is cleared, thus after the handler has run */
856 	if (bank->level_mask & irq_mask) {
857 		_set_gpio_irqenable(bank, gpio, 0);
858 		_clear_gpio_irqstatus(bank, gpio);
859 	}
860 
861 	_set_gpio_irqenable(bank, gpio, 1);
862 	spin_unlock_irqrestore(&bank->lock, flags);
863 }
864 
865 static struct irq_chip gpio_irq_chip = {
866 	.name		= "GPIO",
867 	.irq_shutdown	= gpio_irq_shutdown,
868 	.irq_ack	= gpio_ack_irq,
869 	.irq_mask	= gpio_mask_irq,
870 	.irq_unmask	= gpio_unmask_irq,
871 	.irq_set_type	= gpio_irq_type,
872 	.irq_set_wake	= gpio_wake_enable,
873 };
874 
875 /*---------------------------------------------------------------------*/
876 
877 static int omap_mpuio_suspend_noirq(struct device *dev)
878 {
879 	struct platform_device *pdev = to_platform_device(dev);
880 	struct gpio_bank	*bank = platform_get_drvdata(pdev);
881 	void __iomem		*mask_reg = bank->base +
882 					OMAP_MPUIO_GPIO_MASKIT / bank->stride;
883 	unsigned long		flags;
884 
885 	spin_lock_irqsave(&bank->lock, flags);
886 	__raw_writel(0xffff & ~bank->context.wake_en, mask_reg);
887 	spin_unlock_irqrestore(&bank->lock, flags);
888 
889 	return 0;
890 }
891 
892 static int omap_mpuio_resume_noirq(struct device *dev)
893 {
894 	struct platform_device *pdev = to_platform_device(dev);
895 	struct gpio_bank	*bank = platform_get_drvdata(pdev);
896 	void __iomem		*mask_reg = bank->base +
897 					OMAP_MPUIO_GPIO_MASKIT / bank->stride;
898 	unsigned long		flags;
899 
900 	spin_lock_irqsave(&bank->lock, flags);
901 	__raw_writel(bank->context.wake_en, mask_reg);
902 	spin_unlock_irqrestore(&bank->lock, flags);
903 
904 	return 0;
905 }
906 
907 static const struct dev_pm_ops omap_mpuio_dev_pm_ops = {
908 	.suspend_noirq = omap_mpuio_suspend_noirq,
909 	.resume_noirq = omap_mpuio_resume_noirq,
910 };
911 
912 /* use platform_driver for this. */
913 static struct platform_driver omap_mpuio_driver = {
914 	.driver		= {
915 		.name	= "mpuio",
916 		.pm	= &omap_mpuio_dev_pm_ops,
917 	},
918 };
919 
920 static struct platform_device omap_mpuio_device = {
921 	.name		= "mpuio",
922 	.id		= -1,
923 	.dev = {
924 		.driver = &omap_mpuio_driver.driver,
925 	}
926 	/* could list the /proc/iomem resources */
927 };
928 
929 static inline void mpuio_init(struct gpio_bank *bank)
930 {
931 	platform_set_drvdata(&omap_mpuio_device, bank);
932 
933 	if (platform_driver_register(&omap_mpuio_driver) == 0)
934 		(void) platform_device_register(&omap_mpuio_device);
935 }
936 
937 /*---------------------------------------------------------------------*/
938 
939 static int gpio_input(struct gpio_chip *chip, unsigned offset)
940 {
941 	struct gpio_bank *bank;
942 	unsigned long flags;
943 
944 	bank = container_of(chip, struct gpio_bank, chip);
945 	spin_lock_irqsave(&bank->lock, flags);
946 	_set_gpio_direction(bank, offset, 1);
947 	spin_unlock_irqrestore(&bank->lock, flags);
948 	return 0;
949 }
950 
951 static int gpio_get(struct gpio_chip *chip, unsigned offset)
952 {
953 	struct gpio_bank *bank;
954 	u32 mask;
955 
956 	bank = container_of(chip, struct gpio_bank, chip);
957 	mask = (1 << offset);
958 
959 	if (gpio_is_input(bank, mask))
960 		return _get_gpio_datain(bank, offset);
961 	else
962 		return _get_gpio_dataout(bank, offset);
963 }
964 
965 static int gpio_output(struct gpio_chip *chip, unsigned offset, int value)
966 {
967 	struct gpio_bank *bank;
968 	unsigned long flags;
969 
970 	bank = container_of(chip, struct gpio_bank, chip);
971 	spin_lock_irqsave(&bank->lock, flags);
972 	bank->set_dataout(bank, offset, value);
973 	_set_gpio_direction(bank, offset, 0);
974 	spin_unlock_irqrestore(&bank->lock, flags);
975 	return 0;
976 }
977 
978 static int gpio_debounce(struct gpio_chip *chip, unsigned offset,
979 		unsigned debounce)
980 {
981 	struct gpio_bank *bank;
982 	unsigned long flags;
983 
984 	bank = container_of(chip, struct gpio_bank, chip);
985 
986 	spin_lock_irqsave(&bank->lock, flags);
987 	_set_gpio_debounce(bank, offset, debounce);
988 	spin_unlock_irqrestore(&bank->lock, flags);
989 
990 	return 0;
991 }
992 
993 static void gpio_set(struct gpio_chip *chip, unsigned offset, int value)
994 {
995 	struct gpio_bank *bank;
996 	unsigned long flags;
997 
998 	bank = container_of(chip, struct gpio_bank, chip);
999 	spin_lock_irqsave(&bank->lock, flags);
1000 	bank->set_dataout(bank, offset, value);
1001 	spin_unlock_irqrestore(&bank->lock, flags);
1002 }
1003 
1004 /*---------------------------------------------------------------------*/
1005 
1006 static void __init omap_gpio_show_rev(struct gpio_bank *bank)
1007 {
1008 	static bool called;
1009 	u32 rev;
1010 
1011 	if (called || bank->regs->revision == USHRT_MAX)
1012 		return;
1013 
1014 	rev = __raw_readw(bank->base + bank->regs->revision);
1015 	pr_info("OMAP GPIO hardware version %d.%d\n",
1016 		(rev >> 4) & 0x0f, rev & 0x0f);
1017 
1018 	called = true;
1019 }
1020 
1021 /* This lock class tells lockdep that GPIO irqs are in a different
1022  * category than their parents, so it won't report false recursion.
1023  */
1024 static struct lock_class_key gpio_lock_class;
1025 
1026 static void omap_gpio_mod_init(struct gpio_bank *bank)
1027 {
1028 	void __iomem *base = bank->base;
1029 	u32 l = 0xffffffff;
1030 
1031 	if (bank->width == 16)
1032 		l = 0xffff;
1033 
1034 	if (bank->is_mpuio) {
1035 		__raw_writel(l, bank->base + bank->regs->irqenable);
1036 		return;
1037 	}
1038 
1039 	_gpio_rmw(base, bank->regs->irqenable, l, bank->regs->irqenable_inv);
1040 	_gpio_rmw(base, bank->regs->irqstatus, l, !bank->regs->irqenable_inv);
1041 	if (bank->regs->debounce_en)
1042 		__raw_writel(0, base + bank->regs->debounce_en);
1043 
1044 	/* Save OE default value (0xffffffff) in the context */
1045 	bank->context.oe = __raw_readl(bank->base + bank->regs->direction);
1046 	 /* Initialize interface clk ungated, module enabled */
1047 	if (bank->regs->ctrl)
1048 		__raw_writel(0, base + bank->regs->ctrl);
1049 
1050 	bank->dbck = clk_get(bank->dev, "dbclk");
1051 	if (IS_ERR(bank->dbck))
1052 		dev_err(bank->dev, "Could not get gpio dbck\n");
1053 }
1054 
1055 static void
1056 omap_mpuio_alloc_gc(struct gpio_bank *bank, unsigned int irq_start,
1057 		    unsigned int num)
1058 {
1059 	struct irq_chip_generic *gc;
1060 	struct irq_chip_type *ct;
1061 
1062 	gc = irq_alloc_generic_chip("MPUIO", 1, irq_start, bank->base,
1063 				    handle_simple_irq);
1064 	if (!gc) {
1065 		dev_err(bank->dev, "Memory alloc failed for gc\n");
1066 		return;
1067 	}
1068 
1069 	ct = gc->chip_types;
1070 
1071 	/* NOTE: No ack required, reading IRQ status clears it. */
1072 	ct->chip.irq_mask = irq_gc_mask_set_bit;
1073 	ct->chip.irq_unmask = irq_gc_mask_clr_bit;
1074 	ct->chip.irq_set_type = gpio_irq_type;
1075 
1076 	if (bank->regs->wkup_en)
1077 		ct->chip.irq_set_wake = gpio_wake_enable;
1078 
1079 	ct->regs.mask = OMAP_MPUIO_GPIO_INT / bank->stride;
1080 	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
1081 			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
1082 }
1083 
1084 static void omap_gpio_chip_init(struct gpio_bank *bank)
1085 {
1086 	int j;
1087 	static int gpio;
1088 
1089 	/*
1090 	 * REVISIT eventually switch from OMAP-specific gpio structs
1091 	 * over to the generic ones
1092 	 */
1093 	bank->chip.request = omap_gpio_request;
1094 	bank->chip.free = omap_gpio_free;
1095 	bank->chip.direction_input = gpio_input;
1096 	bank->chip.get = gpio_get;
1097 	bank->chip.direction_output = gpio_output;
1098 	bank->chip.set_debounce = gpio_debounce;
1099 	bank->chip.set = gpio_set;
1100 	bank->chip.to_irq = omap_gpio_to_irq;
1101 	if (bank->is_mpuio) {
1102 		bank->chip.label = "mpuio";
1103 		if (bank->regs->wkup_en)
1104 			bank->chip.dev = &omap_mpuio_device.dev;
1105 		bank->chip.base = OMAP_MPUIO(0);
1106 	} else {
1107 		bank->chip.label = "gpio";
1108 		bank->chip.base = gpio;
1109 		gpio += bank->width;
1110 	}
1111 	bank->chip.ngpio = bank->width;
1112 
1113 	gpiochip_add(&bank->chip);
1114 
1115 	for (j = 0; j < bank->width; j++) {
1116 		int irq = irq_create_mapping(bank->domain, j);
1117 		irq_set_lockdep_class(irq, &gpio_lock_class);
1118 		irq_set_chip_data(irq, bank);
1119 		if (bank->is_mpuio) {
1120 			omap_mpuio_alloc_gc(bank, irq, bank->width);
1121 		} else {
1122 			irq_set_chip_and_handler(irq, &gpio_irq_chip,
1123 						 handle_simple_irq);
1124 			set_irq_flags(irq, IRQF_VALID);
1125 		}
1126 	}
1127 	irq_set_chained_handler(bank->irq, gpio_irq_handler);
1128 	irq_set_handler_data(bank->irq, bank);
1129 }
1130 
1131 static const struct of_device_id omap_gpio_match[];
1132 
1133 static int omap_gpio_probe(struct platform_device *pdev)
1134 {
1135 	struct device *dev = &pdev->dev;
1136 	struct device_node *node = dev->of_node;
1137 	const struct of_device_id *match;
1138 	const struct omap_gpio_platform_data *pdata;
1139 	struct resource *res;
1140 	struct gpio_bank *bank;
1141 #ifdef CONFIG_ARCH_OMAP1
1142 	int irq_base;
1143 #endif
1144 
1145 	match = of_match_device(of_match_ptr(omap_gpio_match), dev);
1146 
1147 	pdata = match ? match->data : dev_get_platdata(dev);
1148 	if (!pdata)
1149 		return -EINVAL;
1150 
1151 	bank = devm_kzalloc(dev, sizeof(struct gpio_bank), GFP_KERNEL);
1152 	if (!bank) {
1153 		dev_err(dev, "Memory alloc failed\n");
1154 		return -ENOMEM;
1155 	}
1156 
1157 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1158 	if (unlikely(!res)) {
1159 		dev_err(dev, "Invalid IRQ resource\n");
1160 		return -ENODEV;
1161 	}
1162 
1163 	bank->irq = res->start;
1164 	bank->dev = dev;
1165 	bank->dbck_flag = pdata->dbck_flag;
1166 	bank->stride = pdata->bank_stride;
1167 	bank->width = pdata->bank_width;
1168 	bank->is_mpuio = pdata->is_mpuio;
1169 	bank->non_wakeup_gpios = pdata->non_wakeup_gpios;
1170 	bank->regs = pdata->regs;
1171 #ifdef CONFIG_OF_GPIO
1172 	bank->chip.of_node = of_node_get(node);
1173 #endif
1174 	if (node) {
1175 		if (!of_property_read_bool(node, "ti,gpio-always-on"))
1176 			bank->loses_context = true;
1177 	} else {
1178 		bank->loses_context = pdata->loses_context;
1179 
1180 		if (bank->loses_context)
1181 			bank->get_context_loss_count =
1182 				pdata->get_context_loss_count;
1183 	}
1184 
1185 #ifdef CONFIG_ARCH_OMAP1
1186 	/*
1187 	 * REVISIT: Once we have OMAP1 supporting SPARSE_IRQ, we can drop
1188 	 * irq_alloc_descs() and irq_domain_add_legacy() and just use a
1189 	 * linear IRQ domain mapping for all OMAP platforms.
1190 	 */
1191 	irq_base = irq_alloc_descs(-1, 0, bank->width, 0);
1192 	if (irq_base < 0) {
1193 		dev_err(dev, "Couldn't allocate IRQ numbers\n");
1194 		return -ENODEV;
1195 	}
1196 
1197 	bank->domain = irq_domain_add_legacy(node, bank->width, irq_base,
1198 					     0, &irq_domain_simple_ops, NULL);
1199 #else
1200 	bank->domain = irq_domain_add_linear(node, bank->width,
1201 					     &irq_domain_simple_ops, NULL);
1202 #endif
1203 	if (!bank->domain) {
1204 		dev_err(dev, "Couldn't register an IRQ domain\n");
1205 		return -ENODEV;
1206 	}
1207 
1208 	if (bank->regs->set_dataout && bank->regs->clr_dataout)
1209 		bank->set_dataout = _set_gpio_dataout_reg;
1210 	else
1211 		bank->set_dataout = _set_gpio_dataout_mask;
1212 
1213 	spin_lock_init(&bank->lock);
1214 
1215 	/* Static mapping, never released */
1216 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1217 	if (unlikely(!res)) {
1218 		dev_err(dev, "Invalid mem resource\n");
1219 		irq_domain_remove(bank->domain);
1220 		return -ENODEV;
1221 	}
1222 
1223 	if (!devm_request_mem_region(dev, res->start, resource_size(res),
1224 				     pdev->name)) {
1225 		dev_err(dev, "Region already claimed\n");
1226 		irq_domain_remove(bank->domain);
1227 		return -EBUSY;
1228 	}
1229 
1230 	bank->base = devm_ioremap(dev, res->start, resource_size(res));
1231 	if (!bank->base) {
1232 		dev_err(dev, "Could not ioremap\n");
1233 		irq_domain_remove(bank->domain);
1234 		return -ENOMEM;
1235 	}
1236 
1237 	platform_set_drvdata(pdev, bank);
1238 
1239 	pm_runtime_enable(bank->dev);
1240 	pm_runtime_irq_safe(bank->dev);
1241 	pm_runtime_get_sync(bank->dev);
1242 
1243 	if (bank->is_mpuio)
1244 		mpuio_init(bank);
1245 
1246 	omap_gpio_mod_init(bank);
1247 	omap_gpio_chip_init(bank);
1248 	omap_gpio_show_rev(bank);
1249 
1250 	pm_runtime_put(bank->dev);
1251 
1252 	list_add_tail(&bank->node, &omap_gpio_list);
1253 
1254 	return 0;
1255 }
1256 
1257 #ifdef CONFIG_ARCH_OMAP2PLUS
1258 
1259 #if defined(CONFIG_PM_RUNTIME)
1260 static void omap_gpio_restore_context(struct gpio_bank *bank);
1261 
1262 static int omap_gpio_runtime_suspend(struct device *dev)
1263 {
1264 	struct platform_device *pdev = to_platform_device(dev);
1265 	struct gpio_bank *bank = platform_get_drvdata(pdev);
1266 	u32 l1 = 0, l2 = 0;
1267 	unsigned long flags;
1268 	u32 wake_low, wake_hi;
1269 
1270 	spin_lock_irqsave(&bank->lock, flags);
1271 
1272 	/*
1273 	 * Only edges can generate a wakeup event to the PRCM.
1274 	 *
1275 	 * Therefore, ensure any wake-up capable GPIOs have
1276 	 * edge-detection enabled before going idle to ensure a wakeup
1277 	 * to the PRCM is generated on a GPIO transition. (c.f. 34xx
1278 	 * NDA TRM 25.5.3.1)
1279 	 *
1280 	 * The normal values will be restored upon ->runtime_resume()
1281 	 * by writing back the values saved in bank->context.
1282 	 */
1283 	wake_low = bank->context.leveldetect0 & bank->context.wake_en;
1284 	if (wake_low)
1285 		__raw_writel(wake_low | bank->context.fallingdetect,
1286 			     bank->base + bank->regs->fallingdetect);
1287 	wake_hi = bank->context.leveldetect1 & bank->context.wake_en;
1288 	if (wake_hi)
1289 		__raw_writel(wake_hi | bank->context.risingdetect,
1290 			     bank->base + bank->regs->risingdetect);
1291 
1292 	if (!bank->enabled_non_wakeup_gpios)
1293 		goto update_gpio_context_count;
1294 
1295 	if (bank->power_mode != OFF_MODE) {
1296 		bank->power_mode = 0;
1297 		goto update_gpio_context_count;
1298 	}
1299 	/*
1300 	 * If going to OFF, remove triggering for all
1301 	 * non-wakeup GPIOs.  Otherwise spurious IRQs will be
1302 	 * generated.  See OMAP2420 Errata item 1.101.
1303 	 */
1304 	bank->saved_datain = __raw_readl(bank->base +
1305 						bank->regs->datain);
1306 	l1 = bank->context.fallingdetect;
1307 	l2 = bank->context.risingdetect;
1308 
1309 	l1 &= ~bank->enabled_non_wakeup_gpios;
1310 	l2 &= ~bank->enabled_non_wakeup_gpios;
1311 
1312 	__raw_writel(l1, bank->base + bank->regs->fallingdetect);
1313 	__raw_writel(l2, bank->base + bank->regs->risingdetect);
1314 
1315 	bank->workaround_enabled = true;
1316 
1317 update_gpio_context_count:
1318 	if (bank->get_context_loss_count)
1319 		bank->context_loss_count =
1320 				bank->get_context_loss_count(bank->dev);
1321 
1322 	_gpio_dbck_disable(bank);
1323 	spin_unlock_irqrestore(&bank->lock, flags);
1324 
1325 	return 0;
1326 }
1327 
1328 static void omap_gpio_init_context(struct gpio_bank *p);
1329 
1330 static int omap_gpio_runtime_resume(struct device *dev)
1331 {
1332 	struct platform_device *pdev = to_platform_device(dev);
1333 	struct gpio_bank *bank = platform_get_drvdata(pdev);
1334 	u32 l = 0, gen, gen0, gen1;
1335 	unsigned long flags;
1336 	int c;
1337 
1338 	spin_lock_irqsave(&bank->lock, flags);
1339 
1340 	/*
1341 	 * On the first resume during the probe, the context has not
1342 	 * been initialised and so initialise it now. Also initialise
1343 	 * the context loss count.
1344 	 */
1345 	if (bank->loses_context && !bank->context_valid) {
1346 		omap_gpio_init_context(bank);
1347 
1348 		if (bank->get_context_loss_count)
1349 			bank->context_loss_count =
1350 				bank->get_context_loss_count(bank->dev);
1351 	}
1352 
1353 	_gpio_dbck_enable(bank);
1354 
1355 	/*
1356 	 * In ->runtime_suspend(), level-triggered, wakeup-enabled
1357 	 * GPIOs were set to edge trigger also in order to be able to
1358 	 * generate a PRCM wakeup.  Here we restore the
1359 	 * pre-runtime_suspend() values for edge triggering.
1360 	 */
1361 	__raw_writel(bank->context.fallingdetect,
1362 		     bank->base + bank->regs->fallingdetect);
1363 	__raw_writel(bank->context.risingdetect,
1364 		     bank->base + bank->regs->risingdetect);
1365 
1366 	if (bank->loses_context) {
1367 		if (!bank->get_context_loss_count) {
1368 			omap_gpio_restore_context(bank);
1369 		} else {
1370 			c = bank->get_context_loss_count(bank->dev);
1371 			if (c != bank->context_loss_count) {
1372 				omap_gpio_restore_context(bank);
1373 			} else {
1374 				spin_unlock_irqrestore(&bank->lock, flags);
1375 				return 0;
1376 			}
1377 		}
1378 	}
1379 
1380 	if (!bank->workaround_enabled) {
1381 		spin_unlock_irqrestore(&bank->lock, flags);
1382 		return 0;
1383 	}
1384 
1385 	l = __raw_readl(bank->base + bank->regs->datain);
1386 
1387 	/*
1388 	 * Check if any of the non-wakeup interrupt GPIOs have changed
1389 	 * state.  If so, generate an IRQ by software.  This is
1390 	 * horribly racy, but it's the best we can do to work around
1391 	 * this silicon bug.
1392 	 */
1393 	l ^= bank->saved_datain;
1394 	l &= bank->enabled_non_wakeup_gpios;
1395 
1396 	/*
1397 	 * No need to generate IRQs for the rising edge for gpio IRQs
1398 	 * configured with falling edge only; and vice versa.
1399 	 */
1400 	gen0 = l & bank->context.fallingdetect;
1401 	gen0 &= bank->saved_datain;
1402 
1403 	gen1 = l & bank->context.risingdetect;
1404 	gen1 &= ~(bank->saved_datain);
1405 
1406 	/* FIXME: Consider GPIO IRQs with level detections properly! */
1407 	gen = l & (~(bank->context.fallingdetect) &
1408 					 ~(bank->context.risingdetect));
1409 	/* Consider all GPIO IRQs needed to be updated */
1410 	gen |= gen0 | gen1;
1411 
1412 	if (gen) {
1413 		u32 old0, old1;
1414 
1415 		old0 = __raw_readl(bank->base + bank->regs->leveldetect0);
1416 		old1 = __raw_readl(bank->base + bank->regs->leveldetect1);
1417 
1418 		if (!bank->regs->irqstatus_raw0) {
1419 			__raw_writel(old0 | gen, bank->base +
1420 						bank->regs->leveldetect0);
1421 			__raw_writel(old1 | gen, bank->base +
1422 						bank->regs->leveldetect1);
1423 		}
1424 
1425 		if (bank->regs->irqstatus_raw0) {
1426 			__raw_writel(old0 | l, bank->base +
1427 						bank->regs->leveldetect0);
1428 			__raw_writel(old1 | l, bank->base +
1429 						bank->regs->leveldetect1);
1430 		}
1431 		__raw_writel(old0, bank->base + bank->regs->leveldetect0);
1432 		__raw_writel(old1, bank->base + bank->regs->leveldetect1);
1433 	}
1434 
1435 	bank->workaround_enabled = false;
1436 	spin_unlock_irqrestore(&bank->lock, flags);
1437 
1438 	return 0;
1439 }
1440 #endif /* CONFIG_PM_RUNTIME */
1441 
1442 void omap2_gpio_prepare_for_idle(int pwr_mode)
1443 {
1444 	struct gpio_bank *bank;
1445 
1446 	list_for_each_entry(bank, &omap_gpio_list, node) {
1447 		if (!BANK_USED(bank) || !bank->loses_context)
1448 			continue;
1449 
1450 		bank->power_mode = pwr_mode;
1451 
1452 		pm_runtime_put_sync_suspend(bank->dev);
1453 	}
1454 }
1455 
1456 void omap2_gpio_resume_after_idle(void)
1457 {
1458 	struct gpio_bank *bank;
1459 
1460 	list_for_each_entry(bank, &omap_gpio_list, node) {
1461 		if (!BANK_USED(bank) || !bank->loses_context)
1462 			continue;
1463 
1464 		pm_runtime_get_sync(bank->dev);
1465 	}
1466 }
1467 
1468 #if defined(CONFIG_PM_RUNTIME)
1469 static void omap_gpio_init_context(struct gpio_bank *p)
1470 {
1471 	struct omap_gpio_reg_offs *regs = p->regs;
1472 	void __iomem *base = p->base;
1473 
1474 	p->context.ctrl		= __raw_readl(base + regs->ctrl);
1475 	p->context.oe		= __raw_readl(base + regs->direction);
1476 	p->context.wake_en	= __raw_readl(base + regs->wkup_en);
1477 	p->context.leveldetect0	= __raw_readl(base + regs->leveldetect0);
1478 	p->context.leveldetect1	= __raw_readl(base + regs->leveldetect1);
1479 	p->context.risingdetect	= __raw_readl(base + regs->risingdetect);
1480 	p->context.fallingdetect = __raw_readl(base + regs->fallingdetect);
1481 	p->context.irqenable1	= __raw_readl(base + regs->irqenable);
1482 	p->context.irqenable2	= __raw_readl(base + regs->irqenable2);
1483 
1484 	if (regs->set_dataout && p->regs->clr_dataout)
1485 		p->context.dataout = __raw_readl(base + regs->set_dataout);
1486 	else
1487 		p->context.dataout = __raw_readl(base + regs->dataout);
1488 
1489 	p->context_valid = true;
1490 }
1491 
1492 static void omap_gpio_restore_context(struct gpio_bank *bank)
1493 {
1494 	__raw_writel(bank->context.wake_en,
1495 				bank->base + bank->regs->wkup_en);
1496 	__raw_writel(bank->context.ctrl, bank->base + bank->regs->ctrl);
1497 	__raw_writel(bank->context.leveldetect0,
1498 				bank->base + bank->regs->leveldetect0);
1499 	__raw_writel(bank->context.leveldetect1,
1500 				bank->base + bank->regs->leveldetect1);
1501 	__raw_writel(bank->context.risingdetect,
1502 				bank->base + bank->regs->risingdetect);
1503 	__raw_writel(bank->context.fallingdetect,
1504 				bank->base + bank->regs->fallingdetect);
1505 	if (bank->regs->set_dataout && bank->regs->clr_dataout)
1506 		__raw_writel(bank->context.dataout,
1507 				bank->base + bank->regs->set_dataout);
1508 	else
1509 		__raw_writel(bank->context.dataout,
1510 				bank->base + bank->regs->dataout);
1511 	__raw_writel(bank->context.oe, bank->base + bank->regs->direction);
1512 
1513 	if (bank->dbck_enable_mask) {
1514 		__raw_writel(bank->context.debounce, bank->base +
1515 					bank->regs->debounce);
1516 		__raw_writel(bank->context.debounce_en,
1517 					bank->base + bank->regs->debounce_en);
1518 	}
1519 
1520 	__raw_writel(bank->context.irqenable1,
1521 				bank->base + bank->regs->irqenable);
1522 	__raw_writel(bank->context.irqenable2,
1523 				bank->base + bank->regs->irqenable2);
1524 }
1525 #endif /* CONFIG_PM_RUNTIME */
1526 #else
1527 #define omap_gpio_runtime_suspend NULL
1528 #define omap_gpio_runtime_resume NULL
1529 static inline void omap_gpio_init_context(struct gpio_bank *p) {}
1530 #endif
1531 
1532 static const struct dev_pm_ops gpio_pm_ops = {
1533 	SET_RUNTIME_PM_OPS(omap_gpio_runtime_suspend, omap_gpio_runtime_resume,
1534 									NULL)
1535 };
1536 
1537 #if defined(CONFIG_OF)
1538 static struct omap_gpio_reg_offs omap2_gpio_regs = {
1539 	.revision =		OMAP24XX_GPIO_REVISION,
1540 	.direction =		OMAP24XX_GPIO_OE,
1541 	.datain =		OMAP24XX_GPIO_DATAIN,
1542 	.dataout =		OMAP24XX_GPIO_DATAOUT,
1543 	.set_dataout =		OMAP24XX_GPIO_SETDATAOUT,
1544 	.clr_dataout =		OMAP24XX_GPIO_CLEARDATAOUT,
1545 	.irqstatus =		OMAP24XX_GPIO_IRQSTATUS1,
1546 	.irqstatus2 =		OMAP24XX_GPIO_IRQSTATUS2,
1547 	.irqenable =		OMAP24XX_GPIO_IRQENABLE1,
1548 	.irqenable2 =		OMAP24XX_GPIO_IRQENABLE2,
1549 	.set_irqenable =	OMAP24XX_GPIO_SETIRQENABLE1,
1550 	.clr_irqenable =	OMAP24XX_GPIO_CLEARIRQENABLE1,
1551 	.debounce =		OMAP24XX_GPIO_DEBOUNCE_VAL,
1552 	.debounce_en =		OMAP24XX_GPIO_DEBOUNCE_EN,
1553 	.ctrl =			OMAP24XX_GPIO_CTRL,
1554 	.wkup_en =		OMAP24XX_GPIO_WAKE_EN,
1555 	.leveldetect0 =		OMAP24XX_GPIO_LEVELDETECT0,
1556 	.leveldetect1 =		OMAP24XX_GPIO_LEVELDETECT1,
1557 	.risingdetect =		OMAP24XX_GPIO_RISINGDETECT,
1558 	.fallingdetect =	OMAP24XX_GPIO_FALLINGDETECT,
1559 };
1560 
1561 static struct omap_gpio_reg_offs omap4_gpio_regs = {
1562 	.revision =		OMAP4_GPIO_REVISION,
1563 	.direction =		OMAP4_GPIO_OE,
1564 	.datain =		OMAP4_GPIO_DATAIN,
1565 	.dataout =		OMAP4_GPIO_DATAOUT,
1566 	.set_dataout =		OMAP4_GPIO_SETDATAOUT,
1567 	.clr_dataout =		OMAP4_GPIO_CLEARDATAOUT,
1568 	.irqstatus =		OMAP4_GPIO_IRQSTATUS0,
1569 	.irqstatus2 =		OMAP4_GPIO_IRQSTATUS1,
1570 	.irqenable =		OMAP4_GPIO_IRQSTATUSSET0,
1571 	.irqenable2 =		OMAP4_GPIO_IRQSTATUSSET1,
1572 	.set_irqenable =	OMAP4_GPIO_IRQSTATUSSET0,
1573 	.clr_irqenable =	OMAP4_GPIO_IRQSTATUSCLR0,
1574 	.debounce =		OMAP4_GPIO_DEBOUNCINGTIME,
1575 	.debounce_en =		OMAP4_GPIO_DEBOUNCENABLE,
1576 	.ctrl =			OMAP4_GPIO_CTRL,
1577 	.wkup_en =		OMAP4_GPIO_IRQWAKEN0,
1578 	.leveldetect0 =		OMAP4_GPIO_LEVELDETECT0,
1579 	.leveldetect1 =		OMAP4_GPIO_LEVELDETECT1,
1580 	.risingdetect =		OMAP4_GPIO_RISINGDETECT,
1581 	.fallingdetect =	OMAP4_GPIO_FALLINGDETECT,
1582 };
1583 
1584 static const struct omap_gpio_platform_data omap2_pdata = {
1585 	.regs = &omap2_gpio_regs,
1586 	.bank_width = 32,
1587 	.dbck_flag = false,
1588 };
1589 
1590 static const struct omap_gpio_platform_data omap3_pdata = {
1591 	.regs = &omap2_gpio_regs,
1592 	.bank_width = 32,
1593 	.dbck_flag = true,
1594 };
1595 
1596 static const struct omap_gpio_platform_data omap4_pdata = {
1597 	.regs = &omap4_gpio_regs,
1598 	.bank_width = 32,
1599 	.dbck_flag = true,
1600 };
1601 
1602 static const struct of_device_id omap_gpio_match[] = {
1603 	{
1604 		.compatible = "ti,omap4-gpio",
1605 		.data = &omap4_pdata,
1606 	},
1607 	{
1608 		.compatible = "ti,omap3-gpio",
1609 		.data = &omap3_pdata,
1610 	},
1611 	{
1612 		.compatible = "ti,omap2-gpio",
1613 		.data = &omap2_pdata,
1614 	},
1615 	{ },
1616 };
1617 MODULE_DEVICE_TABLE(of, omap_gpio_match);
1618 #endif
1619 
1620 static struct platform_driver omap_gpio_driver = {
1621 	.probe		= omap_gpio_probe,
1622 	.driver		= {
1623 		.name	= "omap_gpio",
1624 		.pm	= &gpio_pm_ops,
1625 		.of_match_table = of_match_ptr(omap_gpio_match),
1626 	},
1627 };
1628 
1629 /*
1630  * gpio driver register needs to be done before
1631  * machine_init functions access gpio APIs.
1632  * Hence omap_gpio_drv_reg() is a postcore_initcall.
1633  */
1634 static int __init omap_gpio_drv_reg(void)
1635 {
1636 	return platform_driver_register(&omap_gpio_driver);
1637 }
1638 postcore_initcall(omap_gpio_drv_reg);
1639