ARM: mvebu: Fix kernel hang in mvebu_soc_id_init() when of_iomap failed
[linux-2.6/btrfs-unstable.git] / drivers / gpio / gpio-pxa.c
blobcc13d1b74fad09f06c0d2bd42cc4d41b196df2cf
1 /*
2 * linux/arch/arm/plat-pxa/gpio.c
4 * Generic PXA GPIO handling
6 * Author: Nicolas Pitre
7 * Created: Jun 15, 2001
8 * Copyright: MontaVista Software Inc.
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.
14 #include <linux/module.h>
15 #include <linux/clk.h>
16 #include <linux/err.h>
17 #include <linux/gpio.h>
18 #include <linux/gpio-pxa.h>
19 #include <linux/init.h>
20 #include <linux/irq.h>
21 #include <linux/irqdomain.h>
22 #include <linux/irqchip/chained_irq.h>
23 #include <linux/io.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/platform_device.h>
27 #include <linux/syscore_ops.h>
28 #include <linux/slab.h>
30 #include <mach/irqs.h>
33 * We handle the GPIOs by banks, each bank covers up to 32 GPIOs with
34 * one set of registers. The register offsets are organized below:
36 * GPLR GPDR GPSR GPCR GRER GFER GEDR
37 * BANK 0 - 0x0000 0x000C 0x0018 0x0024 0x0030 0x003C 0x0048
38 * BANK 1 - 0x0004 0x0010 0x001C 0x0028 0x0034 0x0040 0x004C
39 * BANK 2 - 0x0008 0x0014 0x0020 0x002C 0x0038 0x0044 0x0050
41 * BANK 3 - 0x0100 0x010C 0x0118 0x0124 0x0130 0x013C 0x0148
42 * BANK 4 - 0x0104 0x0110 0x011C 0x0128 0x0134 0x0140 0x014C
43 * BANK 5 - 0x0108 0x0114 0x0120 0x012C 0x0138 0x0144 0x0150
45 * NOTE:
46 * BANK 3 is only available on PXA27x and later processors.
47 * BANK 4 and 5 are only available on PXA935
50 #define GPLR_OFFSET 0x00
51 #define GPDR_OFFSET 0x0C
52 #define GPSR_OFFSET 0x18
53 #define GPCR_OFFSET 0x24
54 #define GRER_OFFSET 0x30
55 #define GFER_OFFSET 0x3C
56 #define GEDR_OFFSET 0x48
57 #define GAFR_OFFSET 0x54
58 #define ED_MASK_OFFSET 0x9C /* GPIO edge detection for AP side */
60 #define BANK_OFF(n) (((n) < 3) ? (n) << 2 : 0x100 + (((n) - 3) << 2))
62 int pxa_last_gpio;
63 static int irq_base;
65 #ifdef CONFIG_OF
66 static struct irq_domain *domain;
67 static struct device_node *pxa_gpio_of_node;
68 #endif
70 struct pxa_gpio_chip {
71 struct gpio_chip chip;
72 void __iomem *regbase;
73 char label[10];
75 unsigned long irq_mask;
76 unsigned long irq_edge_rise;
77 unsigned long irq_edge_fall;
78 int (*set_wake)(unsigned int gpio, unsigned int on);
80 #ifdef CONFIG_PM
81 unsigned long saved_gplr;
82 unsigned long saved_gpdr;
83 unsigned long saved_grer;
84 unsigned long saved_gfer;
85 #endif
88 enum pxa_gpio_type {
89 PXA25X_GPIO = 0,
90 PXA26X_GPIO,
91 PXA27X_GPIO,
92 PXA3XX_GPIO,
93 PXA93X_GPIO,
94 MMP_GPIO = 0x10,
95 MMP2_GPIO,
98 struct pxa_gpio_id {
99 enum pxa_gpio_type type;
100 int gpio_nums;
103 static DEFINE_SPINLOCK(gpio_lock);
104 static struct pxa_gpio_chip *pxa_gpio_chips;
105 static enum pxa_gpio_type gpio_type;
106 static void __iomem *gpio_reg_base;
108 static struct pxa_gpio_id pxa25x_id = {
109 .type = PXA25X_GPIO,
110 .gpio_nums = 85,
113 static struct pxa_gpio_id pxa26x_id = {
114 .type = PXA26X_GPIO,
115 .gpio_nums = 90,
118 static struct pxa_gpio_id pxa27x_id = {
119 .type = PXA27X_GPIO,
120 .gpio_nums = 121,
123 static struct pxa_gpio_id pxa3xx_id = {
124 .type = PXA3XX_GPIO,
125 .gpio_nums = 128,
128 static struct pxa_gpio_id pxa93x_id = {
129 .type = PXA93X_GPIO,
130 .gpio_nums = 192,
133 static struct pxa_gpio_id mmp_id = {
134 .type = MMP_GPIO,
135 .gpio_nums = 128,
138 static struct pxa_gpio_id mmp2_id = {
139 .type = MMP2_GPIO,
140 .gpio_nums = 192,
143 #define for_each_gpio_chip(i, c) \
144 for (i = 0, c = &pxa_gpio_chips[0]; i <= pxa_last_gpio; i += 32, c++)
146 static inline void __iomem *gpio_chip_base(struct gpio_chip *c)
148 return container_of(c, struct pxa_gpio_chip, chip)->regbase;
151 static inline struct pxa_gpio_chip *gpio_to_pxachip(unsigned gpio)
153 return &pxa_gpio_chips[gpio_to_bank(gpio)];
156 static inline int gpio_is_pxa_type(int type)
158 return (type & MMP_GPIO) == 0;
161 static inline int gpio_is_mmp_type(int type)
163 return (type & MMP_GPIO) != 0;
166 /* GPIO86/87/88/89 on PXA26x have their direction bits in PXA_GPDR(2 inverted,
167 * as well as their Alternate Function value being '1' for GPIO in GAFRx.
169 static inline int __gpio_is_inverted(int gpio)
171 if ((gpio_type == PXA26X_GPIO) && (gpio > 85))
172 return 1;
173 return 0;
177 * On PXA25x and PXA27x, GAFRx and GPDRx together decide the alternate
178 * function of a GPIO, and GPDRx cannot be altered once configured. It
179 * is attributed as "occupied" here (I know this terminology isn't
180 * accurate, you are welcome to propose a better one :-)
182 static inline int __gpio_is_occupied(unsigned gpio)
184 struct pxa_gpio_chip *pxachip;
185 void __iomem *base;
186 unsigned long gafr = 0, gpdr = 0;
187 int ret, af = 0, dir = 0;
189 pxachip = gpio_to_pxachip(gpio);
190 base = gpio_chip_base(&pxachip->chip);
191 gpdr = readl_relaxed(base + GPDR_OFFSET);
193 switch (gpio_type) {
194 case PXA25X_GPIO:
195 case PXA26X_GPIO:
196 case PXA27X_GPIO:
197 gafr = readl_relaxed(base + GAFR_OFFSET);
198 af = (gafr >> ((gpio & 0xf) * 2)) & 0x3;
199 dir = gpdr & GPIO_bit(gpio);
201 if (__gpio_is_inverted(gpio))
202 ret = (af != 1) || (dir == 0);
203 else
204 ret = (af != 0) || (dir != 0);
205 break;
206 default:
207 ret = gpdr & GPIO_bit(gpio);
208 break;
210 return ret;
213 static int pxa_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
215 return chip->base + offset + irq_base;
218 int pxa_irq_to_gpio(int irq)
220 return irq - irq_base;
223 static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
225 void __iomem *base = gpio_chip_base(chip);
226 uint32_t value, mask = 1 << offset;
227 unsigned long flags;
229 spin_lock_irqsave(&gpio_lock, flags);
231 value = readl_relaxed(base + GPDR_OFFSET);
232 if (__gpio_is_inverted(chip->base + offset))
233 value |= mask;
234 else
235 value &= ~mask;
236 writel_relaxed(value, base + GPDR_OFFSET);
238 spin_unlock_irqrestore(&gpio_lock, flags);
239 return 0;
242 static int pxa_gpio_direction_output(struct gpio_chip *chip,
243 unsigned offset, int value)
245 void __iomem *base = gpio_chip_base(chip);
246 uint32_t tmp, mask = 1 << offset;
247 unsigned long flags;
249 writel_relaxed(mask, base + (value ? GPSR_OFFSET : GPCR_OFFSET));
251 spin_lock_irqsave(&gpio_lock, flags);
253 tmp = readl_relaxed(base + GPDR_OFFSET);
254 if (__gpio_is_inverted(chip->base + offset))
255 tmp &= ~mask;
256 else
257 tmp |= mask;
258 writel_relaxed(tmp, base + GPDR_OFFSET);
260 spin_unlock_irqrestore(&gpio_lock, flags);
261 return 0;
264 static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
266 return readl_relaxed(gpio_chip_base(chip) + GPLR_OFFSET) & (1 << offset);
269 static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
271 writel_relaxed(1 << offset, gpio_chip_base(chip) +
272 (value ? GPSR_OFFSET : GPCR_OFFSET));
275 #ifdef CONFIG_OF_GPIO
276 static int pxa_gpio_of_xlate(struct gpio_chip *gc,
277 const struct of_phandle_args *gpiospec,
278 u32 *flags)
280 if (gpiospec->args[0] > pxa_last_gpio)
281 return -EINVAL;
283 if (gc != &pxa_gpio_chips[gpiospec->args[0] / 32].chip)
284 return -EINVAL;
286 if (flags)
287 *flags = gpiospec->args[1];
289 return gpiospec->args[0] % 32;
291 #endif
293 static int pxa_init_gpio_chip(int gpio_end,
294 int (*set_wake)(unsigned int, unsigned int))
296 int i, gpio, nbanks = gpio_to_bank(gpio_end) + 1;
297 struct pxa_gpio_chip *chips;
299 chips = kzalloc(nbanks * sizeof(struct pxa_gpio_chip), GFP_KERNEL);
300 if (chips == NULL) {
301 pr_err("%s: failed to allocate GPIO chips\n", __func__);
302 return -ENOMEM;
305 for (i = 0, gpio = 0; i < nbanks; i++, gpio += 32) {
306 struct gpio_chip *c = &chips[i].chip;
308 sprintf(chips[i].label, "gpio-%d", i);
309 chips[i].regbase = gpio_reg_base + BANK_OFF(i);
310 chips[i].set_wake = set_wake;
312 c->base = gpio;
313 c->label = chips[i].label;
315 c->direction_input = pxa_gpio_direction_input;
316 c->direction_output = pxa_gpio_direction_output;
317 c->get = pxa_gpio_get;
318 c->set = pxa_gpio_set;
319 c->to_irq = pxa_gpio_to_irq;
320 #ifdef CONFIG_OF_GPIO
321 c->of_node = pxa_gpio_of_node;
322 c->of_xlate = pxa_gpio_of_xlate;
323 c->of_gpio_n_cells = 2;
324 #endif
326 /* number of GPIOs on last bank may be less than 32 */
327 c->ngpio = (gpio + 31 > gpio_end) ? (gpio_end - gpio + 1) : 32;
328 gpiochip_add(c);
330 pxa_gpio_chips = chips;
331 return 0;
334 /* Update only those GRERx and GFERx edge detection register bits if those
335 * bits are set in c->irq_mask
337 static inline void update_edge_detect(struct pxa_gpio_chip *c)
339 uint32_t grer, gfer;
341 grer = readl_relaxed(c->regbase + GRER_OFFSET) & ~c->irq_mask;
342 gfer = readl_relaxed(c->regbase + GFER_OFFSET) & ~c->irq_mask;
343 grer |= c->irq_edge_rise & c->irq_mask;
344 gfer |= c->irq_edge_fall & c->irq_mask;
345 writel_relaxed(grer, c->regbase + GRER_OFFSET);
346 writel_relaxed(gfer, c->regbase + GFER_OFFSET);
349 static int pxa_gpio_irq_type(struct irq_data *d, unsigned int type)
351 struct pxa_gpio_chip *c;
352 int gpio = pxa_irq_to_gpio(d->irq);
353 unsigned long gpdr, mask = GPIO_bit(gpio);
355 c = gpio_to_pxachip(gpio);
357 if (type == IRQ_TYPE_PROBE) {
358 /* Don't mess with enabled GPIOs using preconfigured edges or
359 * GPIOs set to alternate function or to output during probe
361 if ((c->irq_edge_rise | c->irq_edge_fall) & GPIO_bit(gpio))
362 return 0;
364 if (__gpio_is_occupied(gpio))
365 return 0;
367 type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
370 gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);
372 if (__gpio_is_inverted(gpio))
373 writel_relaxed(gpdr | mask, c->regbase + GPDR_OFFSET);
374 else
375 writel_relaxed(gpdr & ~mask, c->regbase + GPDR_OFFSET);
377 if (type & IRQ_TYPE_EDGE_RISING)
378 c->irq_edge_rise |= mask;
379 else
380 c->irq_edge_rise &= ~mask;
382 if (type & IRQ_TYPE_EDGE_FALLING)
383 c->irq_edge_fall |= mask;
384 else
385 c->irq_edge_fall &= ~mask;
387 update_edge_detect(c);
389 pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, d->irq, gpio,
390 ((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
391 ((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
392 return 0;
395 static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
397 struct pxa_gpio_chip *c;
398 int loop, gpio, gpio_base, n;
399 unsigned long gedr;
400 struct irq_chip *chip = irq_desc_get_chip(desc);
402 chained_irq_enter(chip, desc);
404 do {
405 loop = 0;
406 for_each_gpio_chip(gpio, c) {
407 gpio_base = c->chip.base;
409 gedr = readl_relaxed(c->regbase + GEDR_OFFSET);
410 gedr = gedr & c->irq_mask;
411 writel_relaxed(gedr, c->regbase + GEDR_OFFSET);
413 for_each_set_bit(n, &gedr, BITS_PER_LONG) {
414 loop = 1;
416 generic_handle_irq(gpio_to_irq(gpio_base + n));
419 } while (loop);
421 chained_irq_exit(chip, desc);
424 static void pxa_ack_muxed_gpio(struct irq_data *d)
426 int gpio = pxa_irq_to_gpio(d->irq);
427 struct pxa_gpio_chip *c = gpio_to_pxachip(gpio);
429 writel_relaxed(GPIO_bit(gpio), c->regbase + GEDR_OFFSET);
432 static void pxa_mask_muxed_gpio(struct irq_data *d)
434 int gpio = pxa_irq_to_gpio(d->irq);
435 struct pxa_gpio_chip *c = gpio_to_pxachip(gpio);
436 uint32_t grer, gfer;
438 c->irq_mask &= ~GPIO_bit(gpio);
440 grer = readl_relaxed(c->regbase + GRER_OFFSET) & ~GPIO_bit(gpio);
441 gfer = readl_relaxed(c->regbase + GFER_OFFSET) & ~GPIO_bit(gpio);
442 writel_relaxed(grer, c->regbase + GRER_OFFSET);
443 writel_relaxed(gfer, c->regbase + GFER_OFFSET);
446 static int pxa_gpio_set_wake(struct irq_data *d, unsigned int on)
448 int gpio = pxa_irq_to_gpio(d->irq);
449 struct pxa_gpio_chip *c = gpio_to_pxachip(gpio);
451 if (c->set_wake)
452 return c->set_wake(gpio, on);
453 else
454 return 0;
457 static void pxa_unmask_muxed_gpio(struct irq_data *d)
459 int gpio = pxa_irq_to_gpio(d->irq);
460 struct pxa_gpio_chip *c = gpio_to_pxachip(gpio);
462 c->irq_mask |= GPIO_bit(gpio);
463 update_edge_detect(c);
466 static struct irq_chip pxa_muxed_gpio_chip = {
467 .name = "GPIO",
468 .irq_ack = pxa_ack_muxed_gpio,
469 .irq_mask = pxa_mask_muxed_gpio,
470 .irq_unmask = pxa_unmask_muxed_gpio,
471 .irq_set_type = pxa_gpio_irq_type,
472 .irq_set_wake = pxa_gpio_set_wake,
475 static int pxa_gpio_nums(struct platform_device *pdev)
477 const struct platform_device_id *id = platform_get_device_id(pdev);
478 struct pxa_gpio_id *pxa_id = (struct pxa_gpio_id *)id->driver_data;
479 int count = 0;
481 switch (pxa_id->type) {
482 case PXA25X_GPIO:
483 case PXA26X_GPIO:
484 case PXA27X_GPIO:
485 case PXA3XX_GPIO:
486 case PXA93X_GPIO:
487 case MMP_GPIO:
488 case MMP2_GPIO:
489 gpio_type = pxa_id->type;
490 count = pxa_id->gpio_nums - 1;
491 break;
492 default:
493 count = -EINVAL;
494 break;
496 return count;
499 #ifdef CONFIG_OF
500 static struct of_device_id pxa_gpio_dt_ids[] = {
501 { .compatible = "intel,pxa25x-gpio", .data = &pxa25x_id, },
502 { .compatible = "intel,pxa26x-gpio", .data = &pxa26x_id, },
503 { .compatible = "intel,pxa27x-gpio", .data = &pxa27x_id, },
504 { .compatible = "intel,pxa3xx-gpio", .data = &pxa3xx_id, },
505 { .compatible = "marvell,pxa93x-gpio", .data = &pxa93x_id, },
506 { .compatible = "marvell,mmp-gpio", .data = &mmp_id, },
507 { .compatible = "marvell,mmp2-gpio", .data = &mmp2_id, },
511 static int pxa_irq_domain_map(struct irq_domain *d, unsigned int irq,
512 irq_hw_number_t hw)
514 irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
515 handle_edge_irq);
516 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
517 return 0;
520 const struct irq_domain_ops pxa_irq_domain_ops = {
521 .map = pxa_irq_domain_map,
522 .xlate = irq_domain_xlate_twocell,
525 static int pxa_gpio_probe_dt(struct platform_device *pdev)
527 int ret = 0, nr_gpios;
528 struct device_node *np = pdev->dev.of_node;
529 const struct of_device_id *of_id =
530 of_match_device(pxa_gpio_dt_ids, &pdev->dev);
531 const struct pxa_gpio_id *gpio_id;
533 if (!of_id || !of_id->data) {
534 dev_err(&pdev->dev, "Failed to find gpio controller\n");
535 return -EFAULT;
537 gpio_id = of_id->data;
538 gpio_type = gpio_id->type;
540 nr_gpios = gpio_id->gpio_nums;
541 pxa_last_gpio = nr_gpios - 1;
543 irq_base = irq_alloc_descs(-1, 0, nr_gpios, 0);
544 if (irq_base < 0) {
545 dev_err(&pdev->dev, "Failed to allocate IRQ numbers\n");
546 ret = irq_base;
547 goto err;
549 domain = irq_domain_add_legacy(np, nr_gpios, irq_base, 0,
550 &pxa_irq_domain_ops, NULL);
551 pxa_gpio_of_node = np;
552 return 0;
553 err:
554 iounmap(gpio_reg_base);
555 return ret;
557 #else
558 #define pxa_gpio_probe_dt(pdev) (-1)
559 #endif
561 static int pxa_gpio_probe(struct platform_device *pdev)
563 struct pxa_gpio_chip *c;
564 struct resource *res;
565 struct clk *clk;
566 struct pxa_gpio_platform_data *info;
567 int gpio, irq, ret, use_of = 0;
568 int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;
570 info = dev_get_platdata(&pdev->dev);
571 if (info) {
572 irq_base = info->irq_base;
573 if (irq_base <= 0)
574 return -EINVAL;
575 pxa_last_gpio = pxa_gpio_nums(pdev);
576 } else {
577 irq_base = 0;
578 use_of = 1;
579 ret = pxa_gpio_probe_dt(pdev);
580 if (ret < 0)
581 return -EINVAL;
584 if (!pxa_last_gpio)
585 return -EINVAL;
587 irq0 = platform_get_irq_byname(pdev, "gpio0");
588 irq1 = platform_get_irq_byname(pdev, "gpio1");
589 irq_mux = platform_get_irq_byname(pdev, "gpio_mux");
590 if ((irq0 > 0 && irq1 <= 0) || (irq0 <= 0 && irq1 > 0)
591 || (irq_mux <= 0))
592 return -EINVAL;
593 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
594 if (!res)
595 return -EINVAL;
596 gpio_reg_base = ioremap(res->start, resource_size(res));
597 if (!gpio_reg_base)
598 return -EINVAL;
600 if (irq0 > 0)
601 gpio_offset = 2;
603 clk = clk_get(&pdev->dev, NULL);
604 if (IS_ERR(clk)) {
605 dev_err(&pdev->dev, "Error %ld to get gpio clock\n",
606 PTR_ERR(clk));
607 iounmap(gpio_reg_base);
608 return PTR_ERR(clk);
610 ret = clk_prepare_enable(clk);
611 if (ret) {
612 clk_put(clk);
613 iounmap(gpio_reg_base);
614 return ret;
617 /* Initialize GPIO chips */
618 pxa_init_gpio_chip(pxa_last_gpio, info ? info->gpio_set_wake : NULL);
620 /* clear all GPIO edge detects */
621 for_each_gpio_chip(gpio, c) {
622 writel_relaxed(0, c->regbase + GFER_OFFSET);
623 writel_relaxed(0, c->regbase + GRER_OFFSET);
624 writel_relaxed(~0, c->regbase + GEDR_OFFSET);
625 /* unmask GPIO edge detect for AP side */
626 if (gpio_is_mmp_type(gpio_type))
627 writel_relaxed(~0, c->regbase + ED_MASK_OFFSET);
630 if (!use_of) {
631 #ifdef CONFIG_ARCH_PXA
632 irq = gpio_to_irq(0);
633 irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
634 handle_edge_irq);
635 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
636 irq_set_chained_handler(IRQ_GPIO0, pxa_gpio_demux_handler);
638 irq = gpio_to_irq(1);
639 irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
640 handle_edge_irq);
641 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
642 irq_set_chained_handler(IRQ_GPIO1, pxa_gpio_demux_handler);
643 #endif
645 for (irq = gpio_to_irq(gpio_offset);
646 irq <= gpio_to_irq(pxa_last_gpio); irq++) {
647 irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
648 handle_edge_irq);
649 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
653 irq_set_chained_handler(irq_mux, pxa_gpio_demux_handler);
654 return 0;
657 static const struct platform_device_id gpio_id_table[] = {
658 { "pxa25x-gpio", (unsigned long)&pxa25x_id },
659 { "pxa26x-gpio", (unsigned long)&pxa26x_id },
660 { "pxa27x-gpio", (unsigned long)&pxa27x_id },
661 { "pxa3xx-gpio", (unsigned long)&pxa3xx_id },
662 { "pxa93x-gpio", (unsigned long)&pxa93x_id },
663 { "mmp-gpio", (unsigned long)&mmp_id },
664 { "mmp2-gpio", (unsigned long)&mmp2_id },
665 { },
668 static struct platform_driver pxa_gpio_driver = {
669 .probe = pxa_gpio_probe,
670 .driver = {
671 .name = "pxa-gpio",
672 .of_match_table = of_match_ptr(pxa_gpio_dt_ids),
674 .id_table = gpio_id_table,
677 static int __init pxa_gpio_init(void)
679 return platform_driver_register(&pxa_gpio_driver);
681 postcore_initcall(pxa_gpio_init);
683 #ifdef CONFIG_PM
684 static int pxa_gpio_suspend(void)
686 struct pxa_gpio_chip *c;
687 int gpio;
689 for_each_gpio_chip(gpio, c) {
690 c->saved_gplr = readl_relaxed(c->regbase + GPLR_OFFSET);
691 c->saved_gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);
692 c->saved_grer = readl_relaxed(c->regbase + GRER_OFFSET);
693 c->saved_gfer = readl_relaxed(c->regbase + GFER_OFFSET);
695 /* Clear GPIO transition detect bits */
696 writel_relaxed(0xffffffff, c->regbase + GEDR_OFFSET);
698 return 0;
701 static void pxa_gpio_resume(void)
703 struct pxa_gpio_chip *c;
704 int gpio;
706 for_each_gpio_chip(gpio, c) {
707 /* restore level with set/clear */
708 writel_relaxed(c->saved_gplr, c->regbase + GPSR_OFFSET);
709 writel_relaxed(~c->saved_gplr, c->regbase + GPCR_OFFSET);
711 writel_relaxed(c->saved_grer, c->regbase + GRER_OFFSET);
712 writel_relaxed(c->saved_gfer, c->regbase + GFER_OFFSET);
713 writel_relaxed(c->saved_gpdr, c->regbase + GPDR_OFFSET);
716 #else
717 #define pxa_gpio_suspend NULL
718 #define pxa_gpio_resume NULL
719 #endif
721 struct syscore_ops pxa_gpio_syscore_ops = {
722 .suspend = pxa_gpio_suspend,
723 .resume = pxa_gpio_resume,
726 static int __init pxa_gpio_sysinit(void)
728 register_syscore_ops(&pxa_gpio_syscore_ops);
729 return 0;
731 postcore_initcall(pxa_gpio_sysinit);