xref: /linux/drivers/gpio/gpio-nomadik.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * GPIO driver for the IP block found in the Nomadik SoC; it is an AMBA device,
4  * managing 32 pins with alternate functions. It can also handle the STA2X11
5  * block from ST.
6  *
7  * The GPIO chips are shared with pinctrl-nomadik if used; it needs access for
8  * pinmuxing functionality and others.
9  *
10  * This driver also handles the mobileye,eyeq5-gpio compatible. It is an STA2X11
11  * but with only data, direction and interrupts register active. We want to
12  * avoid touching SLPM, RWIMSC, FWIMSC, AFSLA and AFSLB registers; that is,
13  * wake and alternate function registers. It is NOT compatible with
14  * pinctrl-nomadik.
15  *
16  * Copyright (C) 2008,2009 STMicroelectronics
17  * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
18  *   Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
19  * Copyright (C) 2011-2013 Linus Walleij <linus.walleij@linaro.org>
20  */
21 #include <linux/cleanup.h>
22 #include <linux/clk.h>
23 #include <linux/gpio/consumer.h>
24 #include <linux/gpio/driver.h>
25 #include <linux/interrupt.h>
26 #include <linux/kernel.h>
27 #include <linux/mod_devicetable.h>
28 #include <linux/pinctrl/pinctrl.h>
29 #include <linux/platform_device.h>
30 #include <linux/property.h>
31 #include <linux/reset.h>
32 #include <linux/seq_file.h>
33 #include <linux/slab.h>
34 #include <linux/string_choices.h>
35 #include <linux/types.h>
36 
37 #include <linux/gpio/gpio-nomadik.h>
38 
39 #ifndef CONFIG_PINCTRL_NOMADIK
40 static DEFINE_SPINLOCK(nmk_gpio_slpm_lock);
41 #endif
42 
43 void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip, unsigned int offset,
44 			 enum nmk_gpio_slpm mode)
45 {
46 	u32 slpm;
47 
48 	/* We should NOT have been called. */
49 	if (WARN_ON(nmk_chip->is_mobileye_soc))
50 		return;
51 
52 	slpm = readl(nmk_chip->addr + NMK_GPIO_SLPC);
53 	if (mode == NMK_GPIO_SLPM_NOCHANGE)
54 		slpm |= BIT(offset);
55 	else
56 		slpm &= ~BIT(offset);
57 	writel(slpm, nmk_chip->addr + NMK_GPIO_SLPC);
58 }
59 
60 static void __nmk_gpio_set_output(struct nmk_gpio_chip *nmk_chip,
61 				  unsigned int offset, int val)
62 {
63 	if (val)
64 		writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DATS);
65 	else
66 		writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DATC);
67 }
68 
69 void __nmk_gpio_make_output(struct nmk_gpio_chip *nmk_chip,
70 			    unsigned int offset, int val)
71 {
72 	writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DIRS);
73 	__nmk_gpio_set_output(nmk_chip, offset, val);
74 }
75 
76 /* IRQ functions */
77 
78 static void nmk_gpio_irq_ack(struct irq_data *d)
79 {
80 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
81 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
82 
83 	clk_enable(nmk_chip->clk);
84 	writel(BIT(d->hwirq), nmk_chip->addr + NMK_GPIO_IC);
85 	clk_disable(nmk_chip->clk);
86 }
87 
88 enum nmk_gpio_irq_type {
89 	NORMAL,
90 	WAKE,
91 };
92 
93 static void __nmk_gpio_irq_modify(struct nmk_gpio_chip *nmk_chip,
94 				  int offset, enum nmk_gpio_irq_type which,
95 				  bool enable)
96 {
97 	u32 *rimscval;
98 	u32 *fimscval;
99 	u32 rimscreg;
100 	u32 fimscreg;
101 
102 	if (which == NORMAL) {
103 		rimscreg = NMK_GPIO_RIMSC;
104 		fimscreg = NMK_GPIO_FIMSC;
105 		rimscval = &nmk_chip->rimsc;
106 		fimscval = &nmk_chip->fimsc;
107 	} else  {
108 		/* We should NOT have been called. */
109 		if (WARN_ON(nmk_chip->is_mobileye_soc))
110 			return;
111 		rimscreg = NMK_GPIO_RWIMSC;
112 		fimscreg = NMK_GPIO_FWIMSC;
113 		rimscval = &nmk_chip->rwimsc;
114 		fimscval = &nmk_chip->fwimsc;
115 	}
116 
117 	/* we must individually set/clear the two edges */
118 	if (nmk_chip->edge_rising & BIT(offset)) {
119 		if (enable)
120 			*rimscval |= BIT(offset);
121 		else
122 			*rimscval &= ~BIT(offset);
123 		writel(*rimscval, nmk_chip->addr + rimscreg);
124 	}
125 	if (nmk_chip->edge_falling & BIT(offset)) {
126 		if (enable)
127 			*fimscval |= BIT(offset);
128 		else
129 			*fimscval &= ~BIT(offset);
130 		writel(*fimscval, nmk_chip->addr + fimscreg);
131 	}
132 }
133 
134 static void __nmk_gpio_set_wake(struct nmk_gpio_chip *nmk_chip,
135 				int offset, bool on)
136 {
137 	/* We should NOT have been called. */
138 	if (WARN_ON(nmk_chip->is_mobileye_soc))
139 		return;
140 
141 	/*
142 	 * Ensure WAKEUP_ENABLE is on.  No need to disable it if wakeup is
143 	 * disabled, since setting SLPM to 1 increases power consumption, and
144 	 * wakeup is anyhow controlled by the RIMSC and FIMSC registers.
145 	 */
146 	if (nmk_chip->sleepmode && on) {
147 		__nmk_gpio_set_slpm(nmk_chip, offset,
148 				    NMK_GPIO_SLPM_WAKEUP_ENABLE);
149 	}
150 
151 	__nmk_gpio_irq_modify(nmk_chip, offset, WAKE, on);
152 }
153 
154 static void nmk_gpio_irq_maskunmask(struct nmk_gpio_chip *nmk_chip,
155 				    struct irq_data *d, bool enable)
156 {
157 	unsigned long flags;
158 
159 	clk_enable(nmk_chip->clk);
160 	spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
161 	spin_lock(&nmk_chip->lock);
162 
163 	__nmk_gpio_irq_modify(nmk_chip, d->hwirq, NORMAL, enable);
164 
165 	if (!nmk_chip->is_mobileye_soc && !(nmk_chip->real_wake & BIT(d->hwirq)))
166 		__nmk_gpio_set_wake(nmk_chip, d->hwirq, enable);
167 
168 	spin_unlock(&nmk_chip->lock);
169 	spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
170 	clk_disable(nmk_chip->clk);
171 }
172 
173 static void nmk_gpio_irq_mask(struct irq_data *d)
174 {
175 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
176 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
177 
178 	nmk_gpio_irq_maskunmask(nmk_chip, d, false);
179 	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
180 }
181 
182 static void nmk_gpio_irq_unmask(struct irq_data *d)
183 {
184 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
185 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
186 
187 	gpiochip_enable_irq(gc, irqd_to_hwirq(d));
188 	nmk_gpio_irq_maskunmask(nmk_chip, d, true);
189 }
190 
191 static int nmk_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
192 {
193 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
194 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
195 	unsigned long flags;
196 
197 	/* Handler is registered in all cases. */
198 	if (nmk_chip->is_mobileye_soc)
199 		return -ENXIO;
200 
201 	clk_enable(nmk_chip->clk);
202 	spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
203 	spin_lock(&nmk_chip->lock);
204 
205 	if (irqd_irq_disabled(d))
206 		__nmk_gpio_set_wake(nmk_chip, d->hwirq, on);
207 
208 	if (on)
209 		nmk_chip->real_wake |= BIT(d->hwirq);
210 	else
211 		nmk_chip->real_wake &= ~BIT(d->hwirq);
212 
213 	spin_unlock(&nmk_chip->lock);
214 	spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
215 	clk_disable(nmk_chip->clk);
216 
217 	return 0;
218 }
219 
220 static int nmk_gpio_irq_set_type(struct irq_data *d, unsigned int type)
221 {
222 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
223 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
224 	bool enabled = !irqd_irq_disabled(d);
225 	bool wake = irqd_is_wakeup_set(d);
226 	unsigned long flags;
227 
228 	if (type & IRQ_TYPE_LEVEL_HIGH)
229 		return -EINVAL;
230 	if (type & IRQ_TYPE_LEVEL_LOW)
231 		return -EINVAL;
232 
233 	clk_enable(nmk_chip->clk);
234 	spin_lock_irqsave(&nmk_chip->lock, flags);
235 
236 	if (enabled)
237 		__nmk_gpio_irq_modify(nmk_chip, d->hwirq, NORMAL, false);
238 
239 	if (!nmk_chip->is_mobileye_soc && (enabled || wake))
240 		__nmk_gpio_irq_modify(nmk_chip, d->hwirq, WAKE, false);
241 
242 	nmk_chip->edge_rising &= ~BIT(d->hwirq);
243 	if (type & IRQ_TYPE_EDGE_RISING)
244 		nmk_chip->edge_rising |= BIT(d->hwirq);
245 
246 	nmk_chip->edge_falling &= ~BIT(d->hwirq);
247 	if (type & IRQ_TYPE_EDGE_FALLING)
248 		nmk_chip->edge_falling |= BIT(d->hwirq);
249 
250 	if (enabled)
251 		__nmk_gpio_irq_modify(nmk_chip, d->hwirq, NORMAL, true);
252 
253 	if (!nmk_chip->is_mobileye_soc && (enabled || wake))
254 		__nmk_gpio_irq_modify(nmk_chip, d->hwirq, WAKE, true);
255 
256 	spin_unlock_irqrestore(&nmk_chip->lock, flags);
257 	clk_disable(nmk_chip->clk);
258 
259 	return 0;
260 }
261 
262 static unsigned int nmk_gpio_irq_startup(struct irq_data *d)
263 {
264 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
265 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
266 
267 	clk_enable(nmk_chip->clk);
268 	nmk_gpio_irq_unmask(d);
269 	return 0;
270 }
271 
272 static void nmk_gpio_irq_shutdown(struct irq_data *d)
273 {
274 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
275 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
276 
277 	nmk_gpio_irq_mask(d);
278 	clk_disable(nmk_chip->clk);
279 }
280 
281 static irqreturn_t nmk_gpio_irq_handler(int irq, void *dev_id)
282 {
283 	struct nmk_gpio_chip *nmk_chip = dev_id;
284 	struct gpio_chip *chip = &nmk_chip->chip;
285 	unsigned long mask = GENMASK(chip->ngpio - 1, 0);
286 	unsigned long status;
287 	int bit;
288 
289 	clk_enable(nmk_chip->clk);
290 
291 	status = readl(nmk_chip->addr + NMK_GPIO_IS);
292 
293 	/* Ensure we cannot leave pending bits; this should never occur. */
294 	if (unlikely(status & ~mask))
295 		writel(status & ~mask, nmk_chip->addr + NMK_GPIO_IC);
296 
297 	clk_disable(nmk_chip->clk);
298 
299 	for_each_set_bit(bit, &status, chip->ngpio)
300 		generic_handle_domain_irq_safe(chip->irq.domain, bit);
301 
302 	return IRQ_RETVAL((status & mask) != 0);
303 }
304 
305 /* I/O Functions */
306 
307 static int nmk_gpio_get_dir(struct gpio_chip *chip, unsigned int offset)
308 {
309 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
310 	int dir;
311 
312 	clk_enable(nmk_chip->clk);
313 
314 	dir = readl(nmk_chip->addr + NMK_GPIO_DIR) & BIT(offset);
315 
316 	clk_disable(nmk_chip->clk);
317 
318 	if (dir)
319 		return GPIO_LINE_DIRECTION_OUT;
320 
321 	return GPIO_LINE_DIRECTION_IN;
322 }
323 
324 static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned int offset)
325 {
326 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
327 
328 	clk_enable(nmk_chip->clk);
329 
330 	writel(BIT(offset), nmk_chip->addr + NMK_GPIO_DIRC);
331 
332 	clk_disable(nmk_chip->clk);
333 
334 	return 0;
335 }
336 
337 static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned int offset)
338 {
339 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
340 	int value;
341 
342 	clk_enable(nmk_chip->clk);
343 
344 	value = !!(readl(nmk_chip->addr + NMK_GPIO_DAT) & BIT(offset));
345 
346 	clk_disable(nmk_chip->clk);
347 
348 	return value;
349 }
350 
351 static int nmk_gpio_set_output(struct gpio_chip *chip, unsigned int offset,
352 			       int val)
353 {
354 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
355 
356 	clk_enable(nmk_chip->clk);
357 
358 	__nmk_gpio_set_output(nmk_chip, offset, val);
359 
360 	clk_disable(nmk_chip->clk);
361 
362 	return 0;
363 }
364 
365 static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned int offset,
366 				int val)
367 {
368 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
369 
370 	clk_enable(nmk_chip->clk);
371 
372 	__nmk_gpio_make_output(nmk_chip, offset, val);
373 
374 	clk_disable(nmk_chip->clk);
375 
376 	return 0;
377 }
378 
379 #ifdef CONFIG_DEBUG_FS
380 
381 static int nmk_gpio_get_mode(struct nmk_gpio_chip *nmk_chip, int offset)
382 {
383 	u32 afunc, bfunc;
384 
385 	/* We don't support modes. */
386 	if (nmk_chip->is_mobileye_soc)
387 		return NMK_GPIO_ALT_GPIO;
388 
389 	clk_enable(nmk_chip->clk);
390 
391 	afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & BIT(offset);
392 	bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & BIT(offset);
393 
394 	clk_disable(nmk_chip->clk);
395 
396 	return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0);
397 }
398 
399 void nmk_gpio_dbg_show_one(struct seq_file *s, struct pinctrl_dev *pctldev,
400 			   struct gpio_chip *chip, unsigned int offset)
401 {
402 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip);
403 #ifdef CONFIG_PINCTRL_NOMADIK
404 	struct gpio_desc *desc;
405 #endif
406 	int mode;
407 	bool is_out;
408 	bool data_out;
409 	bool pull;
410 	static const char * const modes[] = {
411 		[NMK_GPIO_ALT_GPIO]	= "gpio",
412 		[NMK_GPIO_ALT_A]	= "altA",
413 		[NMK_GPIO_ALT_B]	= "altB",
414 		[NMK_GPIO_ALT_C]	= "altC",
415 		[NMK_GPIO_ALT_C + 1]	= "altC1",
416 		[NMK_GPIO_ALT_C + 2]	= "altC2",
417 		[NMK_GPIO_ALT_C + 3]	= "altC3",
418 		[NMK_GPIO_ALT_C + 4]	= "altC4",
419 	};
420 
421 	char *label = gpiochip_dup_line_label(chip, offset);
422 	if (IS_ERR(label))
423 		return;
424 
425 	clk_enable(nmk_chip->clk);
426 	is_out = !!(readl(nmk_chip->addr + NMK_GPIO_DIR) & BIT(offset));
427 	pull = !(readl(nmk_chip->addr + NMK_GPIO_PDIS) & BIT(offset));
428 	data_out = !!(readl(nmk_chip->addr + NMK_GPIO_DAT) & BIT(offset));
429 	mode = nmk_gpio_get_mode(nmk_chip, offset);
430 #ifdef CONFIG_PINCTRL_NOMADIK
431 	if (mode == NMK_GPIO_ALT_C && pctldev) {
432 		desc = gpio_device_get_desc(chip->gpiodev, offset);
433 		mode = nmk_prcm_gpiocr_get_mode(pctldev, desc_to_gpio(desc));
434 	}
435 #endif
436 
437 	if (is_out) {
438 		seq_printf(s, " gpio-%-3d (%-20.20s) out %s           %s",
439 			   offset, label ?: "(none)", str_hi_lo(data_out),
440 			   (mode < 0) ? "unknown" : modes[mode]);
441 	} else {
442 		int irq = chip->to_irq(chip, offset);
443 		const int pullidx = pull ? 1 : 0;
444 		int val;
445 		static const char * const pulls[] = {
446 			"none        ",
447 			"pull enabled",
448 		};
449 
450 		seq_printf(s, " gpio-%-3d (%-20.20s) in  %s %s",
451 			   offset, label ?: "(none)", pulls[pullidx],
452 			   (mode < 0) ? "unknown" : modes[mode]);
453 
454 		val = nmk_gpio_get_input(chip, offset);
455 		seq_printf(s, " VAL %d", val);
456 
457 		/*
458 		 * This races with request_irq(), set_irq_type(),
459 		 * and set_irq_wake() ... but those are "rare".
460 		 */
461 		if (irq > 0 && irq_has_action(irq)) {
462 			char *trigger;
463 			bool wake;
464 
465 			if (nmk_chip->edge_rising & BIT(offset))
466 				trigger = "edge-rising";
467 			else if (nmk_chip->edge_falling & BIT(offset))
468 				trigger = "edge-falling";
469 			else
470 				trigger = "edge-undefined";
471 
472 			wake = !!(nmk_chip->real_wake & BIT(offset));
473 
474 			seq_printf(s, " irq-%d %s%s",
475 				   irq, trigger, wake ? " wakeup" : "");
476 		}
477 	}
478 	clk_disable(nmk_chip->clk);
479 }
480 
481 static void nmk_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
482 {
483 	unsigned int i;
484 
485 	for (i = 0; i < chip->ngpio; i++) {
486 		nmk_gpio_dbg_show_one(s, NULL, chip, i);
487 		seq_puts(s, "\n");
488 	}
489 }
490 
491 #else
492 
493 #define nmk_gpio_dbg_show	NULL
494 
495 #endif
496 
497 /*
498  * We will allocate memory for the state container using devm* allocators
499  * binding to the first device reaching this point, it doesn't matter if
500  * it is the pin controller or GPIO driver. However we need to use the right
501  * platform device when looking up resources so pay attention to pdev.
502  */
503 struct nmk_gpio_chip *nmk_gpio_populate_chip(struct fwnode_handle *fwnode,
504 					     struct platform_device *pdev)
505 {
506 	struct nmk_gpio_chip *nmk_chip;
507 	struct platform_device *gpio_pdev;
508 	struct device *dev = &pdev->dev;
509 	struct reset_control *reset;
510 	struct device *gpio_dev;
511 	struct gpio_chip *chip;
512 	struct resource *res;
513 	struct clk *clk;
514 	void __iomem *base;
515 	u32 id, ngpio;
516 	int ret;
517 
518 	gpio_dev = bus_find_device_by_fwnode(&platform_bus_type, fwnode);
519 	if (!gpio_dev) {
520 		dev_err(dev, "populate \"%pfwP\": device not found\n", fwnode);
521 		return ERR_PTR(-ENODEV);
522 	}
523 	gpio_pdev = to_platform_device(gpio_dev);
524 
525 	if (device_property_read_u32(gpio_dev, "gpio-bank", &id)) {
526 		dev_err(dev, "populate: gpio-bank property not found\n");
527 		platform_device_put(gpio_pdev);
528 		return ERR_PTR(-EINVAL);
529 	}
530 
531 #ifdef CONFIG_PINCTRL_NOMADIK
532 	if (id >= ARRAY_SIZE(nmk_gpio_chips)) {
533 		dev_err(dev, "populate: invalid id: %u\n", id);
534 		platform_device_put(gpio_pdev);
535 		return ERR_PTR(-EINVAL);
536 	}
537 	/* Already populated? */
538 	nmk_chip = nmk_gpio_chips[id];
539 	if (nmk_chip) {
540 		platform_device_put(gpio_pdev);
541 		return nmk_chip;
542 	}
543 #endif
544 
545 	nmk_chip = devm_kzalloc(dev, sizeof(*nmk_chip), GFP_KERNEL);
546 	if (!nmk_chip) {
547 		platform_device_put(gpio_pdev);
548 		return ERR_PTR(-ENOMEM);
549 	}
550 
551 	if (device_property_read_u32(gpio_dev, "ngpios", &ngpio)) {
552 		ngpio = NMK_GPIO_PER_CHIP;
553 		dev_dbg(dev, "populate: using default ngpio (%u)\n", ngpio);
554 	}
555 
556 	nmk_chip->is_mobileye_soc = device_is_compatible(gpio_dev,
557 							 "mobileye,eyeq5-gpio");
558 	nmk_chip->bank = id;
559 	chip = &nmk_chip->chip;
560 	chip->base = -1;
561 	chip->ngpio = ngpio;
562 	chip->label = dev_name(gpio_dev);
563 	chip->parent = gpio_dev;
564 
565 	/* NOTE: different devices! No devm_platform_ioremap_resource() here! */
566 	res = platform_get_resource(gpio_pdev, IORESOURCE_MEM, 0);
567 	base = devm_ioremap_resource(dev, res);
568 	if (IS_ERR(base)) {
569 		platform_device_put(gpio_pdev);
570 		return ERR_CAST(base);
571 	}
572 	nmk_chip->addr = base;
573 
574 	/* NOTE: do not use devm_ here! */
575 	clk = clk_get_optional(gpio_dev, NULL);
576 	if (IS_ERR(clk)) {
577 		platform_device_put(gpio_pdev);
578 		return ERR_CAST(clk);
579 	}
580 	clk_prepare(clk);
581 	nmk_chip->clk = clk;
582 
583 	/* NOTE: do not use devm_ here! */
584 	reset = reset_control_get_optional_shared(gpio_dev, NULL);
585 	if (IS_ERR(reset)) {
586 		clk_unprepare(clk);
587 		clk_put(clk);
588 		platform_device_put(gpio_pdev);
589 		dev_err(dev, "failed getting reset control: %pe\n",
590 			reset);
591 		return ERR_CAST(reset);
592 	}
593 
594 	/*
595 	 * Reset might be shared and asserts/deasserts calls are unbalanced. We
596 	 * only support sharing this reset with other gpio-nomadik devices that
597 	 * use this reset to ensure deassertion at probe.
598 	 */
599 	ret = reset_control_deassert(reset);
600 	if (ret) {
601 		reset_control_put(reset);
602 		clk_unprepare(clk);
603 		clk_put(clk);
604 		platform_device_put(gpio_pdev);
605 		dev_err(dev, "failed reset deassert: %d\n", ret);
606 		return ERR_PTR(ret);
607 	}
608 
609 #ifdef CONFIG_PINCTRL_NOMADIK
610 	nmk_gpio_chips[id] = nmk_chip;
611 #endif
612 	return nmk_chip;
613 }
614 
615 static void nmk_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
616 {
617 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
618 	struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(gc);
619 
620 	seq_printf(p, "nmk%u-%u-%u", nmk_chip->bank,
621 		   gc->base, gc->base + gc->ngpio - 1);
622 }
623 
624 static const struct irq_chip nmk_irq_chip = {
625 	.irq_ack = nmk_gpio_irq_ack,
626 	.irq_mask = nmk_gpio_irq_mask,
627 	.irq_unmask = nmk_gpio_irq_unmask,
628 	.irq_set_type = nmk_gpio_irq_set_type,
629 	.irq_set_wake = nmk_gpio_irq_set_wake,
630 	.irq_startup = nmk_gpio_irq_startup,
631 	.irq_shutdown = nmk_gpio_irq_shutdown,
632 	.irq_print_chip = nmk_gpio_irq_print_chip,
633 	.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
634 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
635 };
636 
637 static int nmk_gpio_probe(struct platform_device *pdev)
638 {
639 	struct device *dev = &pdev->dev;
640 	struct nmk_gpio_chip *nmk_chip;
641 	struct gpio_irq_chip *girq;
642 	bool supports_sleepmode;
643 	struct gpio_chip *chip;
644 	int irq;
645 	int ret;
646 
647 	nmk_chip = nmk_gpio_populate_chip(dev_fwnode(dev), pdev);
648 	if (IS_ERR(nmk_chip)) {
649 		dev_err(dev, "could not populate nmk chip struct\n");
650 		return PTR_ERR(nmk_chip);
651 	}
652 
653 	supports_sleepmode =
654 		device_property_read_bool(dev, "st,supports-sleepmode");
655 
656 	/* Correct platform device ID */
657 	pdev->id = nmk_chip->bank;
658 
659 	irq = platform_get_irq(pdev, 0);
660 	if (irq < 0)
661 		return irq;
662 
663 	/*
664 	 * The virt address in nmk_chip->addr is in the nomadik register space,
665 	 * so we can simply convert the resource address, without remapping
666 	 */
667 	nmk_chip->sleepmode = supports_sleepmode;
668 	spin_lock_init(&nmk_chip->lock);
669 
670 	chip = &nmk_chip->chip;
671 	chip->parent = dev;
672 	chip->request = gpiochip_generic_request;
673 	chip->free = gpiochip_generic_free;
674 	chip->get_direction = nmk_gpio_get_dir;
675 	chip->direction_input = nmk_gpio_make_input;
676 	chip->get = nmk_gpio_get_input;
677 	chip->direction_output = nmk_gpio_make_output;
678 	chip->set = nmk_gpio_set_output;
679 	chip->dbg_show = nmk_gpio_dbg_show;
680 	chip->can_sleep = false;
681 	chip->owner = THIS_MODULE;
682 
683 	girq = &chip->irq;
684 	gpio_irq_chip_set_chip(girq, &nmk_irq_chip);
685 	girq->parent_handler = NULL;
686 	girq->num_parents = 0;
687 	girq->parents = NULL;
688 	girq->default_type = IRQ_TYPE_NONE;
689 	girq->handler = handle_edge_irq;
690 
691 	ret = devm_request_irq(dev, irq, nmk_gpio_irq_handler, IRQF_SHARED,
692 			       dev_name(dev), nmk_chip);
693 	if (ret) {
694 		dev_err(dev, "failed requesting IRQ\n");
695 		return ret;
696 	}
697 
698 	if (!nmk_chip->is_mobileye_soc) {
699 		clk_enable(nmk_chip->clk);
700 		nmk_chip->lowemi = readl_relaxed(nmk_chip->addr + NMK_GPIO_LOWEMI);
701 		clk_disable(nmk_chip->clk);
702 	}
703 
704 	ret = gpiochip_add_data(chip, nmk_chip);
705 	if (ret)
706 		return ret;
707 
708 	platform_set_drvdata(pdev, nmk_chip);
709 
710 	dev_info(dev, "chip registered\n");
711 
712 	return 0;
713 }
714 
715 static const struct of_device_id nmk_gpio_match[] = {
716 	{ .compatible = "st,nomadik-gpio", },
717 	{ .compatible = "mobileye,eyeq5-gpio", },
718 	{}
719 };
720 
721 static struct platform_driver nmk_gpio_driver = {
722 	.driver = {
723 		.name = "nomadik-gpio",
724 		.of_match_table = nmk_gpio_match,
725 		.suppress_bind_attrs = true,
726 	},
727 	.probe = nmk_gpio_probe,
728 };
729 
730 static int __init nmk_gpio_init(void)
731 {
732 	return platform_driver_register(&nmk_gpio_driver);
733 }
734 subsys_initcall(nmk_gpio_init);
735