xref: /openbmc/linux/drivers/gpio/gpio-mxc.c (revision 71de0a05)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
4 // Copyright 2008 Juergen Beisert, kernel@pengutronix.de
5 //
6 // Based on code from Freescale Semiconductor,
7 // Authors: Daniel Mack, Juergen Beisert.
8 // Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
9 
10 #include <linux/clk.h>
11 #include <linux/err.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/irq.h>
16 #include <linux/irqdomain.h>
17 #include <linux/irqchip/chained_irq.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/slab.h>
21 #include <linux/spinlock.h>
22 #include <linux/syscore_ops.h>
23 #include <linux/gpio/driver.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/bug.h>
27 
28 #define IMX_SCU_WAKEUP_OFF		0
29 #define IMX_SCU_WAKEUP_LOW_LVL		4
30 #define IMX_SCU_WAKEUP_FALL_EDGE	5
31 #define IMX_SCU_WAKEUP_RISE_EDGE	6
32 #define IMX_SCU_WAKEUP_HIGH_LVL		7
33 
34 /* device type dependent stuff */
35 struct mxc_gpio_hwdata {
36 	unsigned dr_reg;
37 	unsigned gdir_reg;
38 	unsigned psr_reg;
39 	unsigned icr1_reg;
40 	unsigned icr2_reg;
41 	unsigned imr_reg;
42 	unsigned isr_reg;
43 	int edge_sel_reg;
44 	unsigned low_level;
45 	unsigned high_level;
46 	unsigned rise_edge;
47 	unsigned fall_edge;
48 };
49 
50 struct mxc_gpio_reg_saved {
51 	u32 icr1;
52 	u32 icr2;
53 	u32 imr;
54 	u32 gdir;
55 	u32 edge_sel;
56 	u32 dr;
57 };
58 
59 struct mxc_gpio_port {
60 	struct list_head node;
61 	void __iomem *base;
62 	struct clk *clk;
63 	int irq;
64 	int irq_high;
65 	struct irq_domain *domain;
66 	struct gpio_chip gc;
67 	struct device *dev;
68 	u32 both_edges;
69 	struct mxc_gpio_reg_saved gpio_saved_reg;
70 	bool power_off;
71 	u32 wakeup_pads;
72 	bool is_pad_wakeup;
73 	u32 pad_type[32];
74 	const struct mxc_gpio_hwdata *hwdata;
75 };
76 
77 static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = {
78 	.dr_reg		= 0x1c,
79 	.gdir_reg	= 0x00,
80 	.psr_reg	= 0x24,
81 	.icr1_reg	= 0x28,
82 	.icr2_reg	= 0x2c,
83 	.imr_reg	= 0x30,
84 	.isr_reg	= 0x34,
85 	.edge_sel_reg	= -EINVAL,
86 	.low_level	= 0x03,
87 	.high_level	= 0x02,
88 	.rise_edge	= 0x00,
89 	.fall_edge	= 0x01,
90 };
91 
92 static struct mxc_gpio_hwdata imx31_gpio_hwdata = {
93 	.dr_reg		= 0x00,
94 	.gdir_reg	= 0x04,
95 	.psr_reg	= 0x08,
96 	.icr1_reg	= 0x0c,
97 	.icr2_reg	= 0x10,
98 	.imr_reg	= 0x14,
99 	.isr_reg	= 0x18,
100 	.edge_sel_reg	= -EINVAL,
101 	.low_level	= 0x00,
102 	.high_level	= 0x01,
103 	.rise_edge	= 0x02,
104 	.fall_edge	= 0x03,
105 };
106 
107 static struct mxc_gpio_hwdata imx35_gpio_hwdata = {
108 	.dr_reg		= 0x00,
109 	.gdir_reg	= 0x04,
110 	.psr_reg	= 0x08,
111 	.icr1_reg	= 0x0c,
112 	.icr2_reg	= 0x10,
113 	.imr_reg	= 0x14,
114 	.isr_reg	= 0x18,
115 	.edge_sel_reg	= 0x1c,
116 	.low_level	= 0x00,
117 	.high_level	= 0x01,
118 	.rise_edge	= 0x02,
119 	.fall_edge	= 0x03,
120 };
121 
122 #define GPIO_DR			(port->hwdata->dr_reg)
123 #define GPIO_GDIR		(port->hwdata->gdir_reg)
124 #define GPIO_PSR		(port->hwdata->psr_reg)
125 #define GPIO_ICR1		(port->hwdata->icr1_reg)
126 #define GPIO_ICR2		(port->hwdata->icr2_reg)
127 #define GPIO_IMR		(port->hwdata->imr_reg)
128 #define GPIO_ISR		(port->hwdata->isr_reg)
129 #define GPIO_EDGE_SEL		(port->hwdata->edge_sel_reg)
130 
131 #define GPIO_INT_LOW_LEV	(port->hwdata->low_level)
132 #define GPIO_INT_HIGH_LEV	(port->hwdata->high_level)
133 #define GPIO_INT_RISE_EDGE	(port->hwdata->rise_edge)
134 #define GPIO_INT_FALL_EDGE	(port->hwdata->fall_edge)
135 #define GPIO_INT_BOTH_EDGES	0x4
136 
137 static const struct of_device_id mxc_gpio_dt_ids[] = {
138 	{ .compatible = "fsl,imx1-gpio", .data =  &imx1_imx21_gpio_hwdata },
139 	{ .compatible = "fsl,imx21-gpio", .data = &imx1_imx21_gpio_hwdata },
140 	{ .compatible = "fsl,imx31-gpio", .data = &imx31_gpio_hwdata },
141 	{ .compatible = "fsl,imx35-gpio", .data = &imx35_gpio_hwdata },
142 	{ .compatible = "fsl,imx7d-gpio", .data = &imx35_gpio_hwdata },
143 	{ .compatible = "fsl,imx8dxl-gpio", .data = &imx35_gpio_hwdata },
144 	{ .compatible = "fsl,imx8qm-gpio", .data = &imx35_gpio_hwdata },
145 	{ .compatible = "fsl,imx8qxp-gpio", .data = &imx35_gpio_hwdata },
146 	{ /* sentinel */ }
147 };
148 MODULE_DEVICE_TABLE(of, mxc_gpio_dt_ids);
149 
150 /*
151  * MX2 has one interrupt *for all* gpio ports. The list is used
152  * to save the references to all ports, so that mx2_gpio_irq_handler
153  * can walk through all interrupt status registers.
154  */
155 static LIST_HEAD(mxc_gpio_ports);
156 
157 /* Note: This driver assumes 32 GPIOs are handled in one register */
158 
159 static int gpio_set_irq_type(struct irq_data *d, u32 type)
160 {
161 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
162 	struct mxc_gpio_port *port = gc->private;
163 	unsigned long flags;
164 	u32 bit, val;
165 	u32 gpio_idx = d->hwirq;
166 	int edge;
167 	void __iomem *reg = port->base;
168 
169 	port->both_edges &= ~(1 << gpio_idx);
170 	switch (type) {
171 	case IRQ_TYPE_EDGE_RISING:
172 		edge = GPIO_INT_RISE_EDGE;
173 		break;
174 	case IRQ_TYPE_EDGE_FALLING:
175 		edge = GPIO_INT_FALL_EDGE;
176 		break;
177 	case IRQ_TYPE_EDGE_BOTH:
178 		if (GPIO_EDGE_SEL >= 0) {
179 			edge = GPIO_INT_BOTH_EDGES;
180 		} else {
181 			val = port->gc.get(&port->gc, gpio_idx);
182 			if (val) {
183 				edge = GPIO_INT_LOW_LEV;
184 				pr_debug("mxc: set GPIO %d to low trigger\n", gpio_idx);
185 			} else {
186 				edge = GPIO_INT_HIGH_LEV;
187 				pr_debug("mxc: set GPIO %d to high trigger\n", gpio_idx);
188 			}
189 			port->both_edges |= 1 << gpio_idx;
190 		}
191 		break;
192 	case IRQ_TYPE_LEVEL_LOW:
193 		edge = GPIO_INT_LOW_LEV;
194 		break;
195 	case IRQ_TYPE_LEVEL_HIGH:
196 		edge = GPIO_INT_HIGH_LEV;
197 		break;
198 	default:
199 		return -EINVAL;
200 	}
201 
202 	raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags);
203 
204 	if (GPIO_EDGE_SEL >= 0) {
205 		val = readl(port->base + GPIO_EDGE_SEL);
206 		if (edge == GPIO_INT_BOTH_EDGES)
207 			writel(val | (1 << gpio_idx),
208 				port->base + GPIO_EDGE_SEL);
209 		else
210 			writel(val & ~(1 << gpio_idx),
211 				port->base + GPIO_EDGE_SEL);
212 	}
213 
214 	if (edge != GPIO_INT_BOTH_EDGES) {
215 		reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */
216 		bit = gpio_idx & 0xf;
217 		val = readl(reg) & ~(0x3 << (bit << 1));
218 		writel(val | (edge << (bit << 1)), reg);
219 	}
220 
221 	writel(1 << gpio_idx, port->base + GPIO_ISR);
222 	port->pad_type[gpio_idx] = type;
223 
224 	raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags);
225 
226 	return port->gc.direction_input(&port->gc, gpio_idx);
227 }
228 
229 static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
230 {
231 	void __iomem *reg = port->base;
232 	unsigned long flags;
233 	u32 bit, val;
234 	int edge;
235 
236 	raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags);
237 
238 	reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
239 	bit = gpio & 0xf;
240 	val = readl(reg);
241 	edge = (val >> (bit << 1)) & 3;
242 	val &= ~(0x3 << (bit << 1));
243 	if (edge == GPIO_INT_HIGH_LEV) {
244 		edge = GPIO_INT_LOW_LEV;
245 		pr_debug("mxc: switch GPIO %d to low trigger\n", gpio);
246 	} else if (edge == GPIO_INT_LOW_LEV) {
247 		edge = GPIO_INT_HIGH_LEV;
248 		pr_debug("mxc: switch GPIO %d to high trigger\n", gpio);
249 	} else {
250 		pr_err("mxc: invalid configuration for GPIO %d: %x\n",
251 		       gpio, edge);
252 		goto unlock;
253 	}
254 	writel(val | (edge << (bit << 1)), reg);
255 
256 unlock:
257 	raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags);
258 }
259 
260 /* handle 32 interrupts in one status register */
261 static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
262 {
263 	while (irq_stat != 0) {
264 		int irqoffset = fls(irq_stat) - 1;
265 
266 		if (port->both_edges & (1 << irqoffset))
267 			mxc_flip_edge(port, irqoffset);
268 
269 		generic_handle_domain_irq(port->domain, irqoffset);
270 
271 		irq_stat &= ~(1 << irqoffset);
272 	}
273 }
274 
275 /* MX1 and MX3 has one interrupt *per* gpio port */
276 static void mx3_gpio_irq_handler(struct irq_desc *desc)
277 {
278 	u32 irq_stat;
279 	struct mxc_gpio_port *port = irq_desc_get_handler_data(desc);
280 	struct irq_chip *chip = irq_desc_get_chip(desc);
281 
282 	if (port->is_pad_wakeup)
283 		return;
284 
285 	chained_irq_enter(chip, desc);
286 
287 	irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR);
288 
289 	mxc_gpio_irq_handler(port, irq_stat);
290 
291 	chained_irq_exit(chip, desc);
292 }
293 
294 /* MX2 has one interrupt *for all* gpio ports */
295 static void mx2_gpio_irq_handler(struct irq_desc *desc)
296 {
297 	u32 irq_msk, irq_stat;
298 	struct mxc_gpio_port *port;
299 	struct irq_chip *chip = irq_desc_get_chip(desc);
300 
301 	chained_irq_enter(chip, desc);
302 
303 	/* walk through all interrupt status registers */
304 	list_for_each_entry(port, &mxc_gpio_ports, node) {
305 		irq_msk = readl(port->base + GPIO_IMR);
306 		if (!irq_msk)
307 			continue;
308 
309 		irq_stat = readl(port->base + GPIO_ISR) & irq_msk;
310 		if (irq_stat)
311 			mxc_gpio_irq_handler(port, irq_stat);
312 	}
313 	chained_irq_exit(chip, desc);
314 }
315 
316 /*
317  * Set interrupt number "irq" in the GPIO as a wake-up source.
318  * While system is running, all registered GPIO interrupts need to have
319  * wake-up enabled. When system is suspended, only selected GPIO interrupts
320  * need to have wake-up enabled.
321  * @param  irq          interrupt source number
322  * @param  enable       enable as wake-up if equal to non-zero
323  * @return       This function returns 0 on success.
324  */
325 static int gpio_set_wake_irq(struct irq_data *d, u32 enable)
326 {
327 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
328 	struct mxc_gpio_port *port = gc->private;
329 	u32 gpio_idx = d->hwirq;
330 	int ret;
331 
332 	if (enable) {
333 		if (port->irq_high && (gpio_idx >= 16))
334 			ret = enable_irq_wake(port->irq_high);
335 		else
336 			ret = enable_irq_wake(port->irq);
337 		port->wakeup_pads |= (1 << gpio_idx);
338 	} else {
339 		if (port->irq_high && (gpio_idx >= 16))
340 			ret = disable_irq_wake(port->irq_high);
341 		else
342 			ret = disable_irq_wake(port->irq);
343 		port->wakeup_pads &= ~(1 << gpio_idx);
344 	}
345 
346 	return ret;
347 }
348 
349 static int mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base)
350 {
351 	struct irq_chip_generic *gc;
352 	struct irq_chip_type *ct;
353 	int rv;
354 
355 	gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxc", 1, irq_base,
356 					 port->base, handle_level_irq);
357 	if (!gc)
358 		return -ENOMEM;
359 	gc->private = port;
360 
361 	ct = gc->chip_types;
362 	ct->chip.irq_ack = irq_gc_ack_set_bit;
363 	ct->chip.irq_mask = irq_gc_mask_clr_bit;
364 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
365 	ct->chip.irq_set_type = gpio_set_irq_type;
366 	ct->chip.irq_set_wake = gpio_set_wake_irq;
367 	ct->chip.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND;
368 	ct->regs.ack = GPIO_ISR;
369 	ct->regs.mask = GPIO_IMR;
370 
371 	rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
372 					 IRQ_GC_INIT_NESTED_LOCK,
373 					 IRQ_NOREQUEST, 0);
374 
375 	return rv;
376 }
377 
378 static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
379 {
380 	struct mxc_gpio_port *port = gpiochip_get_data(gc);
381 
382 	return irq_find_mapping(port->domain, offset);
383 }
384 
385 static int mxc_gpio_probe(struct platform_device *pdev)
386 {
387 	struct device_node *np = pdev->dev.of_node;
388 	struct mxc_gpio_port *port;
389 	int irq_count;
390 	int irq_base;
391 	int err;
392 
393 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
394 	if (!port)
395 		return -ENOMEM;
396 
397 	port->dev = &pdev->dev;
398 	port->hwdata = device_get_match_data(&pdev->dev);
399 
400 	port->base = devm_platform_ioremap_resource(pdev, 0);
401 	if (IS_ERR(port->base))
402 		return PTR_ERR(port->base);
403 
404 	irq_count = platform_irq_count(pdev);
405 	if (irq_count < 0)
406 		return irq_count;
407 
408 	if (irq_count > 1) {
409 		port->irq_high = platform_get_irq(pdev, 1);
410 		if (port->irq_high < 0)
411 			port->irq_high = 0;
412 	}
413 
414 	port->irq = platform_get_irq(pdev, 0);
415 	if (port->irq < 0)
416 		return port->irq;
417 
418 	/* the controller clock is optional */
419 	port->clk = devm_clk_get_optional(&pdev->dev, NULL);
420 	if (IS_ERR(port->clk))
421 		return PTR_ERR(port->clk);
422 
423 	err = clk_prepare_enable(port->clk);
424 	if (err) {
425 		dev_err(&pdev->dev, "Unable to enable clock.\n");
426 		return err;
427 	}
428 
429 	if (of_device_is_compatible(np, "fsl,imx7d-gpio"))
430 		port->power_off = true;
431 
432 	/* disable the interrupt and clear the status */
433 	writel(0, port->base + GPIO_IMR);
434 	writel(~0, port->base + GPIO_ISR);
435 
436 	if (of_device_is_compatible(np, "fsl,imx21-gpio")) {
437 		/*
438 		 * Setup one handler for all GPIO interrupts. Actually setting
439 		 * the handler is needed only once, but doing it for every port
440 		 * is more robust and easier.
441 		 */
442 		irq_set_chained_handler(port->irq, mx2_gpio_irq_handler);
443 	} else {
444 		/* setup one handler for each entry */
445 		irq_set_chained_handler_and_data(port->irq,
446 						 mx3_gpio_irq_handler, port);
447 		if (port->irq_high > 0)
448 			/* setup handler for GPIO 16 to 31 */
449 			irq_set_chained_handler_and_data(port->irq_high,
450 							 mx3_gpio_irq_handler,
451 							 port);
452 	}
453 
454 	err = bgpio_init(&port->gc, &pdev->dev, 4,
455 			 port->base + GPIO_PSR,
456 			 port->base + GPIO_DR, NULL,
457 			 port->base + GPIO_GDIR, NULL,
458 			 BGPIOF_READ_OUTPUT_REG_SET);
459 	if (err)
460 		goto out_bgio;
461 
462 	port->gc.request = gpiochip_generic_request;
463 	port->gc.free = gpiochip_generic_free;
464 	port->gc.to_irq = mxc_gpio_to_irq;
465 	port->gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 :
466 					     pdev->id * 32;
467 
468 	err = devm_gpiochip_add_data(&pdev->dev, &port->gc, port);
469 	if (err)
470 		goto out_bgio;
471 
472 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
473 	if (irq_base < 0) {
474 		err = irq_base;
475 		goto out_bgio;
476 	}
477 
478 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
479 					     &irq_domain_simple_ops, NULL);
480 	if (!port->domain) {
481 		err = -ENODEV;
482 		goto out_bgio;
483 	}
484 
485 	/* gpio-mxc can be a generic irq chip */
486 	err = mxc_gpio_init_gc(port, irq_base);
487 	if (err < 0)
488 		goto out_irqdomain_remove;
489 
490 	list_add_tail(&port->node, &mxc_gpio_ports);
491 
492 	platform_set_drvdata(pdev, port);
493 
494 	return 0;
495 
496 out_irqdomain_remove:
497 	irq_domain_remove(port->domain);
498 out_bgio:
499 	clk_disable_unprepare(port->clk);
500 	dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
501 	return err;
502 }
503 
504 static void mxc_gpio_save_regs(struct mxc_gpio_port *port)
505 {
506 	if (!port->power_off)
507 		return;
508 
509 	port->gpio_saved_reg.icr1 = readl(port->base + GPIO_ICR1);
510 	port->gpio_saved_reg.icr2 = readl(port->base + GPIO_ICR2);
511 	port->gpio_saved_reg.imr = readl(port->base + GPIO_IMR);
512 	port->gpio_saved_reg.gdir = readl(port->base + GPIO_GDIR);
513 	port->gpio_saved_reg.edge_sel = readl(port->base + GPIO_EDGE_SEL);
514 	port->gpio_saved_reg.dr = readl(port->base + GPIO_DR);
515 }
516 
517 static void mxc_gpio_restore_regs(struct mxc_gpio_port *port)
518 {
519 	if (!port->power_off)
520 		return;
521 
522 	writel(port->gpio_saved_reg.icr1, port->base + GPIO_ICR1);
523 	writel(port->gpio_saved_reg.icr2, port->base + GPIO_ICR2);
524 	writel(port->gpio_saved_reg.imr, port->base + GPIO_IMR);
525 	writel(port->gpio_saved_reg.gdir, port->base + GPIO_GDIR);
526 	writel(port->gpio_saved_reg.edge_sel, port->base + GPIO_EDGE_SEL);
527 	writel(port->gpio_saved_reg.dr, port->base + GPIO_DR);
528 }
529 
530 static bool mxc_gpio_generic_config(struct mxc_gpio_port *port,
531 		unsigned int offset, unsigned long conf)
532 {
533 	struct device_node *np = port->dev->of_node;
534 
535 	if (of_device_is_compatible(np, "fsl,imx8dxl-gpio") ||
536 	    of_device_is_compatible(np, "fsl,imx8qxp-gpio") ||
537 	    of_device_is_compatible(np, "fsl,imx8qm-gpio"))
538 		return (gpiochip_generic_config(&port->gc, offset, conf) == 0);
539 
540 	return false;
541 }
542 
543 static bool mxc_gpio_set_pad_wakeup(struct mxc_gpio_port *port, bool enable)
544 {
545 	unsigned long config;
546 	bool ret = false;
547 	int i, type;
548 
549 	static const u32 pad_type_map[] = {
550 		IMX_SCU_WAKEUP_OFF,		/* 0 */
551 		IMX_SCU_WAKEUP_RISE_EDGE,	/* IRQ_TYPE_EDGE_RISING */
552 		IMX_SCU_WAKEUP_FALL_EDGE,	/* IRQ_TYPE_EDGE_FALLING */
553 		IMX_SCU_WAKEUP_FALL_EDGE,	/* IRQ_TYPE_EDGE_BOTH */
554 		IMX_SCU_WAKEUP_HIGH_LVL,	/* IRQ_TYPE_LEVEL_HIGH */
555 		IMX_SCU_WAKEUP_OFF,		/* 5 */
556 		IMX_SCU_WAKEUP_OFF,		/* 6 */
557 		IMX_SCU_WAKEUP_OFF,		/* 7 */
558 		IMX_SCU_WAKEUP_LOW_LVL,		/* IRQ_TYPE_LEVEL_LOW */
559 	};
560 
561 	for (i = 0; i < 32; i++) {
562 		if ((port->wakeup_pads & (1 << i))) {
563 			type = port->pad_type[i];
564 			if (enable)
565 				config = pad_type_map[type];
566 			else
567 				config = IMX_SCU_WAKEUP_OFF;
568 			ret |= mxc_gpio_generic_config(port, i, config);
569 		}
570 	}
571 
572 	return ret;
573 }
574 
575 static int __maybe_unused mxc_gpio_noirq_suspend(struct device *dev)
576 {
577 	struct platform_device *pdev = to_platform_device(dev);
578 	struct mxc_gpio_port *port = platform_get_drvdata(pdev);
579 
580 	if (port->wakeup_pads > 0)
581 		port->is_pad_wakeup = mxc_gpio_set_pad_wakeup(port, true);
582 
583 	return 0;
584 }
585 
586 static int __maybe_unused mxc_gpio_noirq_resume(struct device *dev)
587 {
588 	struct platform_device *pdev = to_platform_device(dev);
589 	struct mxc_gpio_port *port = platform_get_drvdata(pdev);
590 
591 	if (port->wakeup_pads > 0)
592 		mxc_gpio_set_pad_wakeup(port, false);
593 	port->is_pad_wakeup = false;
594 
595 	return 0;
596 }
597 
598 static const struct dev_pm_ops mxc_gpio_dev_pm_ops = {
599 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mxc_gpio_noirq_suspend, mxc_gpio_noirq_resume)
600 };
601 
602 static int mxc_gpio_syscore_suspend(void)
603 {
604 	struct mxc_gpio_port *port;
605 
606 	/* walk through all ports */
607 	list_for_each_entry(port, &mxc_gpio_ports, node) {
608 		mxc_gpio_save_regs(port);
609 		clk_disable_unprepare(port->clk);
610 	}
611 
612 	return 0;
613 }
614 
615 static void mxc_gpio_syscore_resume(void)
616 {
617 	struct mxc_gpio_port *port;
618 	int ret;
619 
620 	/* walk through all ports */
621 	list_for_each_entry(port, &mxc_gpio_ports, node) {
622 		ret = clk_prepare_enable(port->clk);
623 		if (ret) {
624 			pr_err("mxc: failed to enable gpio clock %d\n", ret);
625 			return;
626 		}
627 		mxc_gpio_restore_regs(port);
628 	}
629 }
630 
631 static struct syscore_ops mxc_gpio_syscore_ops = {
632 	.suspend = mxc_gpio_syscore_suspend,
633 	.resume = mxc_gpio_syscore_resume,
634 };
635 
636 static struct platform_driver mxc_gpio_driver = {
637 	.driver		= {
638 		.name	= "gpio-mxc",
639 		.of_match_table = mxc_gpio_dt_ids,
640 		.suppress_bind_attrs = true,
641 		.pm = &mxc_gpio_dev_pm_ops,
642 	},
643 	.probe		= mxc_gpio_probe,
644 };
645 
646 static int __init gpio_mxc_init(void)
647 {
648 	register_syscore_ops(&mxc_gpio_syscore_ops);
649 
650 	return platform_driver_register(&mxc_gpio_driver);
651 }
652 subsys_initcall(gpio_mxc_init);
653 
654 MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
655 MODULE_DESCRIPTION("i.MX GPIO Driver");
656 MODULE_LICENSE("GPL");
657