1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Xilinx gpio driver for xps/axi_gpio IP.
4 *
5 * Copyright 2008 - 2013 Xilinx, Inc.
6 */
7
8#include <linux/bitmap.h>
9#include <linux/bitops.h>
10#include <linux/clk.h>
11#include <linux/errno.h>
12#include <linux/gpio/driver.h>
13#include <linux/init.h>
14#include <linux/interrupt.h>
15#include <linux/io.h>
16#include <linux/irq.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/platform_device.h>
20#include <linux/pm_runtime.h>
21#include <linux/slab.h>
22
23/* Register Offset Definitions */
24#define XGPIO_DATA_OFFSET   (0x0)	/* Data register  */
25#define XGPIO_TRI_OFFSET    (0x4)	/* I/O direction register  */
26
27#define XGPIO_CHANNEL0_OFFSET	0x0
28#define XGPIO_CHANNEL1_OFFSET	0x8
29
30#define XGPIO_GIER_OFFSET	0x11c /* Global Interrupt Enable */
31#define XGPIO_GIER_IE		BIT(31)
32#define XGPIO_IPISR_OFFSET	0x120 /* IP Interrupt Status */
33#define XGPIO_IPIER_OFFSET	0x128 /* IP Interrupt Enable */
34
35/* Read/Write access to the GPIO registers */
36#if defined(CONFIG_ARCH_ZYNQ) || defined(CONFIG_X86)
37# define xgpio_readreg(offset)		readl(offset)
38# define xgpio_writereg(offset, val)	writel(val, offset)
39#else
40# define xgpio_readreg(offset)		__raw_readl(offset)
41# define xgpio_writereg(offset, val)	__raw_writel(val, offset)
42#endif
43
44/**
45 * struct xgpio_instance - Stores information about GPIO device
46 * @gc: GPIO chip
47 * @regs: register block
48 * @hw_map: GPIO pin mapping on hardware side
49 * @sw_map: GPIO pin mapping on software side
50 * @state: GPIO write state shadow register
51 * @last_irq_read: GPIO read state register from last interrupt
52 * @dir: GPIO direction shadow register
53 * @gpio_lock: Lock used for synchronization
54 * @irq: IRQ used by GPIO device
55 * @irqchip: IRQ chip
56 * @enable: GPIO IRQ enable/disable bitfield
57 * @rising_edge: GPIO IRQ rising edge enable/disable bitfield
58 * @falling_edge: GPIO IRQ falling edge enable/disable bitfield
59 * @clk: clock resource for this driver
60 */
61struct xgpio_instance {
62	struct gpio_chip gc;
63	void __iomem *regs;
64	DECLARE_BITMAP(hw_map, 64);
65	DECLARE_BITMAP(sw_map, 64);
66	DECLARE_BITMAP(state, 64);
67	DECLARE_BITMAP(last_irq_read, 64);
68	DECLARE_BITMAP(dir, 64);
69	spinlock_t gpio_lock;	/* For serializing operations */
70	int irq;
71	DECLARE_BITMAP(enable, 64);
72	DECLARE_BITMAP(rising_edge, 64);
73	DECLARE_BITMAP(falling_edge, 64);
74	struct clk *clk;
75};
76
77static inline int xgpio_from_bit(struct xgpio_instance *chip, int bit)
78{
79	return bitmap_bitremap(bit, chip->hw_map, chip->sw_map, 64);
80}
81
82static inline int xgpio_to_bit(struct xgpio_instance *chip, int gpio)
83{
84	return bitmap_bitremap(gpio, chip->sw_map, chip->hw_map, 64);
85}
86
87static inline u32 xgpio_get_value32(const unsigned long *map, int bit)
88{
89	const size_t index = BIT_WORD(bit);
90	const unsigned long offset = (bit % BITS_PER_LONG) & BIT(5);
91
92	return (map[index] >> offset) & 0xFFFFFFFFul;
93}
94
95static inline void xgpio_set_value32(unsigned long *map, int bit, u32 v)
96{
97	const size_t index = BIT_WORD(bit);
98	const unsigned long offset = (bit % BITS_PER_LONG) & BIT(5);
99
100	map[index] &= ~(0xFFFFFFFFul << offset);
101	map[index] |= (unsigned long)v << offset;
102}
103
104static inline int xgpio_regoffset(struct xgpio_instance *chip, int ch)
105{
106	switch (ch) {
107	case 0:
108		return XGPIO_CHANNEL0_OFFSET;
109	case 1:
110		return XGPIO_CHANNEL1_OFFSET;
111	default:
112		return -EINVAL;
113	}
114}
115
116static void xgpio_read_ch(struct xgpio_instance *chip, int reg, int bit, unsigned long *a)
117{
118	void __iomem *addr = chip->regs + reg + xgpio_regoffset(chip, bit / 32);
119
120	xgpio_set_value32(a, bit, xgpio_readreg(addr));
121}
122
123static void xgpio_write_ch(struct xgpio_instance *chip, int reg, int bit, unsigned long *a)
124{
125	void __iomem *addr = chip->regs + reg + xgpio_regoffset(chip, bit / 32);
126
127	xgpio_writereg(addr, xgpio_get_value32(a, bit));
128}
129
130static void xgpio_read_ch_all(struct xgpio_instance *chip, int reg, unsigned long *a)
131{
132	int bit, lastbit = xgpio_to_bit(chip, chip->gc.ngpio - 1);
133
134	for (bit = 0; bit <= lastbit ; bit += 32)
135		xgpio_read_ch(chip, reg, bit, a);
136}
137
138static void xgpio_write_ch_all(struct xgpio_instance *chip, int reg, unsigned long *a)
139{
140	int bit, lastbit = xgpio_to_bit(chip, chip->gc.ngpio - 1);
141
142	for (bit = 0; bit <= lastbit ; bit += 32)
143		xgpio_write_ch(chip, reg, bit, a);
144}
145
146/**
147 * xgpio_get - Read the specified signal of the GPIO device.
148 * @gc:     Pointer to gpio_chip device structure.
149 * @gpio:   GPIO signal number.
150 *
151 * This function reads the specified signal of the GPIO device.
152 *
153 * Return:
154 * 0 if direction of GPIO signals is set as input otherwise it
155 * returns negative error value.
156 */
157static int xgpio_get(struct gpio_chip *gc, unsigned int gpio)
158{
159	struct xgpio_instance *chip = gpiochip_get_data(gc);
160	int bit = xgpio_to_bit(chip, gpio);
161	DECLARE_BITMAP(state, 64);
162
163	xgpio_read_ch(chip, XGPIO_DATA_OFFSET, bit, state);
164
165	return test_bit(bit, state);
166}
167
168/**
169 * xgpio_set - Write the specified signal of the GPIO device.
170 * @gc:     Pointer to gpio_chip device structure.
171 * @gpio:   GPIO signal number.
172 * @val:    Value to be written to specified signal.
173 *
174 * This function writes the specified value in to the specified signal of the
175 * GPIO device.
176 */
177static void xgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
178{
179	unsigned long flags;
180	struct xgpio_instance *chip = gpiochip_get_data(gc);
181	int bit = xgpio_to_bit(chip, gpio);
182
183	spin_lock_irqsave(&chip->gpio_lock, flags);
184
185	/* Write to GPIO signal and set its direction to output */
186	__assign_bit(bit, chip->state, val);
187
188	xgpio_write_ch(chip, XGPIO_DATA_OFFSET, bit, chip->state);
189
190	spin_unlock_irqrestore(&chip->gpio_lock, flags);
191}
192
193/**
194 * xgpio_set_multiple - Write the specified signals of the GPIO device.
195 * @gc:     Pointer to gpio_chip device structure.
196 * @mask:   Mask of the GPIOS to modify.
197 * @bits:   Value to be wrote on each GPIO
198 *
199 * This function writes the specified values into the specified signals of the
200 * GPIO devices.
201 */
202static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
203			       unsigned long *bits)
204{
205	DECLARE_BITMAP(hw_mask, 64);
206	DECLARE_BITMAP(hw_bits, 64);
207	DECLARE_BITMAP(state, 64);
208	unsigned long flags;
209	struct xgpio_instance *chip = gpiochip_get_data(gc);
210
211	bitmap_remap(hw_mask, mask, chip->sw_map, chip->hw_map, 64);
212	bitmap_remap(hw_bits, bits, chip->sw_map, chip->hw_map, 64);
213
214	spin_lock_irqsave(&chip->gpio_lock, flags);
215
216	bitmap_replace(state, chip->state, hw_bits, hw_mask, 64);
217
218	xgpio_write_ch_all(chip, XGPIO_DATA_OFFSET, state);
219
220	bitmap_copy(chip->state, state, 64);
221
222	spin_unlock_irqrestore(&chip->gpio_lock, flags);
223}
224
225/**
226 * xgpio_dir_in - Set the direction of the specified GPIO signal as input.
227 * @gc:     Pointer to gpio_chip device structure.
228 * @gpio:   GPIO signal number.
229 *
230 * Return:
231 * 0 - if direction of GPIO signals is set as input
232 * otherwise it returns negative error value.
233 */
234static int xgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
235{
236	unsigned long flags;
237	struct xgpio_instance *chip = gpiochip_get_data(gc);
238	int bit = xgpio_to_bit(chip, gpio);
239
240	spin_lock_irqsave(&chip->gpio_lock, flags);
241
242	/* Set the GPIO bit in shadow register and set direction as input */
243	__set_bit(bit, chip->dir);
244	xgpio_write_ch(chip, XGPIO_TRI_OFFSET, bit, chip->dir);
245
246	spin_unlock_irqrestore(&chip->gpio_lock, flags);
247
248	return 0;
249}
250
251/**
252 * xgpio_dir_out - Set the direction of the specified GPIO signal as output.
253 * @gc:     Pointer to gpio_chip device structure.
254 * @gpio:   GPIO signal number.
255 * @val:    Value to be written to specified signal.
256 *
257 * This function sets the direction of specified GPIO signal as output.
258 *
259 * Return:
260 * If all GPIO signals of GPIO chip is configured as input then it returns
261 * error otherwise it returns 0.
262 */
263static int xgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
264{
265	unsigned long flags;
266	struct xgpio_instance *chip = gpiochip_get_data(gc);
267	int bit = xgpio_to_bit(chip, gpio);
268
269	spin_lock_irqsave(&chip->gpio_lock, flags);
270
271	/* Write state of GPIO signal */
272	__assign_bit(bit, chip->state, val);
273	xgpio_write_ch(chip, XGPIO_DATA_OFFSET, bit, chip->state);
274
275	/* Clear the GPIO bit in shadow register and set direction as output */
276	__clear_bit(bit, chip->dir);
277	xgpio_write_ch(chip, XGPIO_TRI_OFFSET, bit, chip->dir);
278
279	spin_unlock_irqrestore(&chip->gpio_lock, flags);
280
281	return 0;
282}
283
284/**
285 * xgpio_save_regs - Set initial values of GPIO pins
286 * @chip: Pointer to GPIO instance
287 */
288static void xgpio_save_regs(struct xgpio_instance *chip)
289{
290	xgpio_write_ch_all(chip, XGPIO_DATA_OFFSET, chip->state);
291	xgpio_write_ch_all(chip, XGPIO_TRI_OFFSET, chip->dir);
292}
293
294static int xgpio_request(struct gpio_chip *chip, unsigned int offset)
295{
296	int ret;
297
298	ret = pm_runtime_get_sync(chip->parent);
299	/*
300	 * If the device is already active pm_runtime_get() will return 1 on
301	 * success, but gpio_request still needs to return 0.
302	 */
303	return ret < 0 ? ret : 0;
304}
305
306static void xgpio_free(struct gpio_chip *chip, unsigned int offset)
307{
308	pm_runtime_put(chip->parent);
309}
310
311static int __maybe_unused xgpio_suspend(struct device *dev)
312{
313	struct xgpio_instance *gpio = dev_get_drvdata(dev);
314	struct irq_data *data = irq_get_irq_data(gpio->irq);
315
316	if (!data) {
317		dev_dbg(dev, "IRQ not connected\n");
318		return pm_runtime_force_suspend(dev);
319	}
320
321	if (!irqd_is_wakeup_set(data))
322		return pm_runtime_force_suspend(dev);
323
324	return 0;
325}
326
327/**
328 * xgpio_remove - Remove method for the GPIO device.
329 * @pdev: pointer to the platform device
330 *
331 * This function remove gpiochips and frees all the allocated resources.
332 *
333 * Return: 0 always
334 */
335static int xgpio_remove(struct platform_device *pdev)
336{
337	struct xgpio_instance *gpio = platform_get_drvdata(pdev);
338
339	pm_runtime_get_sync(&pdev->dev);
340	pm_runtime_put_noidle(&pdev->dev);
341	pm_runtime_disable(&pdev->dev);
342	clk_disable_unprepare(gpio->clk);
343
344	return 0;
345}
346
347/**
348 * xgpio_irq_ack - Acknowledge a child GPIO interrupt.
349 * @irq_data: per IRQ and chip data passed down to chip functions
350 * This currently does nothing, but irq_ack is unconditionally called by
351 * handle_edge_irq and therefore must be defined.
352 */
353static void xgpio_irq_ack(struct irq_data *irq_data)
354{
355}
356
357static int __maybe_unused xgpio_resume(struct device *dev)
358{
359	struct xgpio_instance *gpio = dev_get_drvdata(dev);
360	struct irq_data *data = irq_get_irq_data(gpio->irq);
361
362	if (!data) {
363		dev_dbg(dev, "IRQ not connected\n");
364		return pm_runtime_force_resume(dev);
365	}
366
367	if (!irqd_is_wakeup_set(data))
368		return pm_runtime_force_resume(dev);
369
370	return 0;
371}
372
373static int __maybe_unused xgpio_runtime_suspend(struct device *dev)
374{
375	struct xgpio_instance *gpio = dev_get_drvdata(dev);
376
377	clk_disable(gpio->clk);
378
379	return 0;
380}
381
382static int __maybe_unused xgpio_runtime_resume(struct device *dev)
383{
384	struct xgpio_instance *gpio = dev_get_drvdata(dev);
385
386	return clk_enable(gpio->clk);
387}
388
389static const struct dev_pm_ops xgpio_dev_pm_ops = {
390	SET_SYSTEM_SLEEP_PM_OPS(xgpio_suspend, xgpio_resume)
391	SET_RUNTIME_PM_OPS(xgpio_runtime_suspend,
392			   xgpio_runtime_resume, NULL)
393};
394
395/**
396 * xgpio_irq_mask - Write the specified signal of the GPIO device.
397 * @irq_data: per IRQ and chip data passed down to chip functions
398 */
399static void xgpio_irq_mask(struct irq_data *irq_data)
400{
401	unsigned long flags;
402	struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
403	int irq_offset = irqd_to_hwirq(irq_data);
404	int bit = xgpio_to_bit(chip, irq_offset);
405	u32 mask = BIT(bit / 32), temp;
406
407	spin_lock_irqsave(&chip->gpio_lock, flags);
408
409	__clear_bit(bit, chip->enable);
410
411	if (xgpio_get_value32(chip->enable, bit) == 0) {
412		/* Disable per channel interrupt */
413		temp = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
414		temp &= ~mask;
415		xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, temp);
416	}
417	spin_unlock_irqrestore(&chip->gpio_lock, flags);
418
419	gpiochip_disable_irq(&chip->gc, irq_offset);
420}
421
422/**
423 * xgpio_irq_unmask - Write the specified signal of the GPIO device.
424 * @irq_data: per IRQ and chip data passed down to chip functions
425 */
426static void xgpio_irq_unmask(struct irq_data *irq_data)
427{
428	unsigned long flags;
429	struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
430	int irq_offset = irqd_to_hwirq(irq_data);
431	int bit = xgpio_to_bit(chip, irq_offset);
432	u32 old_enable = xgpio_get_value32(chip->enable, bit);
433	u32 mask = BIT(bit / 32), val;
434
435	gpiochip_enable_irq(&chip->gc, irq_offset);
436
437	spin_lock_irqsave(&chip->gpio_lock, flags);
438
439	__set_bit(bit, chip->enable);
440
441	if (old_enable == 0) {
442		/* Clear any existing per-channel interrupts */
443		val = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
444		val &= mask;
445		xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, val);
446
447		/* Update GPIO IRQ read data before enabling interrupt*/
448		xgpio_read_ch(chip, XGPIO_DATA_OFFSET, bit, chip->last_irq_read);
449
450		/* Enable per channel interrupt */
451		val = xgpio_readreg(chip->regs + XGPIO_IPIER_OFFSET);
452		val |= mask;
453		xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, val);
454	}
455
456	spin_unlock_irqrestore(&chip->gpio_lock, flags);
457}
458
459/**
460 * xgpio_set_irq_type - Write the specified signal of the GPIO device.
461 * @irq_data: Per IRQ and chip data passed down to chip functions
462 * @type: Interrupt type that is to be set for the gpio pin
463 *
464 * Return:
465 * 0 if interrupt type is supported otherwise -EINVAL
466 */
467static int xgpio_set_irq_type(struct irq_data *irq_data, unsigned int type)
468{
469	struct xgpio_instance *chip = irq_data_get_irq_chip_data(irq_data);
470	int irq_offset = irqd_to_hwirq(irq_data);
471	int bit = xgpio_to_bit(chip, irq_offset);
472
473	/*
474	 * The Xilinx GPIO hardware provides a single interrupt status
475	 * indication for any state change in a given GPIO channel (bank).
476	 * Therefore, only rising edge or falling edge triggers are
477	 * supported.
478	 */
479	switch (type & IRQ_TYPE_SENSE_MASK) {
480	case IRQ_TYPE_EDGE_BOTH:
481		__set_bit(bit, chip->rising_edge);
482		__set_bit(bit, chip->falling_edge);
483		break;
484	case IRQ_TYPE_EDGE_RISING:
485		__set_bit(bit, chip->rising_edge);
486		__clear_bit(bit, chip->falling_edge);
487		break;
488	case IRQ_TYPE_EDGE_FALLING:
489		__clear_bit(bit, chip->rising_edge);
490		__set_bit(bit, chip->falling_edge);
491		break;
492	default:
493		return -EINVAL;
494	}
495
496	irq_set_handler_locked(irq_data, handle_edge_irq);
497	return 0;
498}
499
500/**
501 * xgpio_irqhandler - Gpio interrupt service routine
502 * @desc: Pointer to interrupt description
503 */
504static void xgpio_irqhandler(struct irq_desc *desc)
505{
506	struct xgpio_instance *chip = irq_desc_get_handler_data(desc);
507	struct gpio_chip *gc = &chip->gc;
508	struct irq_chip *irqchip = irq_desc_get_chip(desc);
509	DECLARE_BITMAP(rising, 64);
510	DECLARE_BITMAP(falling, 64);
511	DECLARE_BITMAP(all, 64);
512	int irq_offset;
513	u32 status;
514	u32 bit;
515
516	status = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
517	xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, status);
518
519	chained_irq_enter(irqchip, desc);
520
521	spin_lock(&chip->gpio_lock);
522
523	xgpio_read_ch_all(chip, XGPIO_DATA_OFFSET, all);
524
525	bitmap_complement(rising, chip->last_irq_read, 64);
526	bitmap_and(rising, rising, all, 64);
527	bitmap_and(rising, rising, chip->enable, 64);
528	bitmap_and(rising, rising, chip->rising_edge, 64);
529
530	bitmap_complement(falling, all, 64);
531	bitmap_and(falling, falling, chip->last_irq_read, 64);
532	bitmap_and(falling, falling, chip->enable, 64);
533	bitmap_and(falling, falling, chip->falling_edge, 64);
534
535	bitmap_copy(chip->last_irq_read, all, 64);
536	bitmap_or(all, rising, falling, 64);
537
538	spin_unlock(&chip->gpio_lock);
539
540	dev_dbg(gc->parent, "IRQ rising %*pb falling %*pb\n", 64, rising, 64, falling);
541
542	for_each_set_bit(bit, all, 64) {
543		irq_offset = xgpio_from_bit(chip, bit);
544		generic_handle_domain_irq(gc->irq.domain, irq_offset);
545	}
546
547	chained_irq_exit(irqchip, desc);
548}
549
550static const struct irq_chip xgpio_irq_chip = {
551	.name = "gpio-xilinx",
552	.irq_ack = xgpio_irq_ack,
553	.irq_mask = xgpio_irq_mask,
554	.irq_unmask = xgpio_irq_unmask,
555	.irq_set_type = xgpio_set_irq_type,
556	.flags = IRQCHIP_IMMUTABLE,
557	GPIOCHIP_IRQ_RESOURCE_HELPERS,
558};
559
560/**
561 * xgpio_probe - Probe method for the GPIO device.
562 * @pdev: pointer to the platform device
563 *
564 * Return:
565 * It returns 0, if the driver is bound to the GPIO device, or
566 * a negative value if there is an error.
567 */
568static int xgpio_probe(struct platform_device *pdev)
569{
570	struct xgpio_instance *chip;
571	int status = 0;
572	struct device_node *np = pdev->dev.of_node;
573	u32 is_dual = 0;
574	u32 width[2];
575	u32 state[2];
576	u32 dir[2];
577	struct gpio_irq_chip *girq;
578	u32 temp;
579
580	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
581	if (!chip)
582		return -ENOMEM;
583
584	platform_set_drvdata(pdev, chip);
585
586	/* First, check if the device is dual-channel */
587	of_property_read_u32(np, "xlnx,is-dual", &is_dual);
588
589	/* Setup defaults */
590	memset32(width, 0, ARRAY_SIZE(width));
591	memset32(state, 0, ARRAY_SIZE(state));
592	memset32(dir, 0xFFFFFFFF, ARRAY_SIZE(dir));
593
594	/* Update GPIO state shadow register with default value */
595	of_property_read_u32(np, "xlnx,dout-default", &state[0]);
596	of_property_read_u32(np, "xlnx,dout-default-2", &state[1]);
597
598	bitmap_from_arr32(chip->state, state, 64);
599
600	/* Update GPIO direction shadow register with default value */
601	of_property_read_u32(np, "xlnx,tri-default", &dir[0]);
602	of_property_read_u32(np, "xlnx,tri-default-2", &dir[1]);
603
604	bitmap_from_arr32(chip->dir, dir, 64);
605
606	/*
607	 * Check device node and parent device node for device width
608	 * and assume default width of 32
609	 */
610	if (of_property_read_u32(np, "xlnx,gpio-width", &width[0]))
611		width[0] = 32;
612
613	if (width[0] > 32)
614		return -EINVAL;
615
616	if (is_dual && of_property_read_u32(np, "xlnx,gpio2-width", &width[1]))
617		width[1] = 32;
618
619	if (width[1] > 32)
620		return -EINVAL;
621
622	/* Setup software pin mapping */
623	bitmap_set(chip->sw_map, 0, width[0] + width[1]);
624
625	/* Setup hardware pin mapping */
626	bitmap_set(chip->hw_map,  0, width[0]);
627	bitmap_set(chip->hw_map, 32, width[1]);
628
629	spin_lock_init(&chip->gpio_lock);
630
631	chip->gc.base = -1;
632	chip->gc.ngpio = bitmap_weight(chip->hw_map, 64);
633	chip->gc.parent = &pdev->dev;
634	chip->gc.direction_input = xgpio_dir_in;
635	chip->gc.direction_output = xgpio_dir_out;
636	chip->gc.get = xgpio_get;
637	chip->gc.set = xgpio_set;
638	chip->gc.request = xgpio_request;
639	chip->gc.free = xgpio_free;
640	chip->gc.set_multiple = xgpio_set_multiple;
641
642	chip->gc.label = dev_name(&pdev->dev);
643
644	chip->regs = devm_platform_ioremap_resource(pdev, 0);
645	if (IS_ERR(chip->regs)) {
646		dev_err(&pdev->dev, "failed to ioremap memory resource\n");
647		return PTR_ERR(chip->regs);
648	}
649
650	chip->clk = devm_clk_get_optional(&pdev->dev, NULL);
651	if (IS_ERR(chip->clk))
652		return dev_err_probe(&pdev->dev, PTR_ERR(chip->clk), "input clock not found.\n");
653
654	status = clk_prepare_enable(chip->clk);
655	if (status < 0) {
656		dev_err(&pdev->dev, "Failed to prepare clk\n");
657		return status;
658	}
659	pm_runtime_get_noresume(&pdev->dev);
660	pm_runtime_set_active(&pdev->dev);
661	pm_runtime_enable(&pdev->dev);
662
663	xgpio_save_regs(chip);
664
665	chip->irq = platform_get_irq_optional(pdev, 0);
666	if (chip->irq <= 0)
667		goto skip_irq;
668
669	/* Disable per-channel interrupts */
670	xgpio_writereg(chip->regs + XGPIO_IPIER_OFFSET, 0);
671	/* Clear any existing per-channel interrupts */
672	temp = xgpio_readreg(chip->regs + XGPIO_IPISR_OFFSET);
673	xgpio_writereg(chip->regs + XGPIO_IPISR_OFFSET, temp);
674	/* Enable global interrupts */
675	xgpio_writereg(chip->regs + XGPIO_GIER_OFFSET, XGPIO_GIER_IE);
676
677	girq = &chip->gc.irq;
678	gpio_irq_chip_set_chip(girq, &xgpio_irq_chip);
679	girq->parent_handler = xgpio_irqhandler;
680	girq->num_parents = 1;
681	girq->parents = devm_kcalloc(&pdev->dev, 1,
682				     sizeof(*girq->parents),
683				     GFP_KERNEL);
684	if (!girq->parents) {
685		status = -ENOMEM;
686		goto err_pm_put;
687	}
688	girq->parents[0] = chip->irq;
689	girq->default_type = IRQ_TYPE_NONE;
690	girq->handler = handle_bad_irq;
691
692skip_irq:
693	status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
694	if (status) {
695		dev_err(&pdev->dev, "failed to add GPIO chip\n");
696		goto err_pm_put;
697	}
698
699	pm_runtime_put(&pdev->dev);
700	return 0;
701
702err_pm_put:
703	pm_runtime_disable(&pdev->dev);
704	pm_runtime_put_noidle(&pdev->dev);
705	clk_disable_unprepare(chip->clk);
706	return status;
707}
708
709static const struct of_device_id xgpio_of_match[] = {
710	{ .compatible = "xlnx,xps-gpio-1.00.a", },
711	{ /* end of list */ },
712};
713
714MODULE_DEVICE_TABLE(of, xgpio_of_match);
715
716static struct platform_driver xgpio_plat_driver = {
717	.probe		= xgpio_probe,
718	.remove		= xgpio_remove,
719	.driver		= {
720			.name = "gpio-xilinx",
721			.of_match_table	= xgpio_of_match,
722			.pm = &xgpio_dev_pm_ops,
723	},
724};
725
726static int __init xgpio_init(void)
727{
728	return platform_driver_register(&xgpio_plat_driver);
729}
730
731subsys_initcall(xgpio_init);
732
733static void __exit xgpio_exit(void)
734{
735	platform_driver_unregister(&xgpio_plat_driver);
736}
737module_exit(xgpio_exit);
738
739MODULE_AUTHOR("Xilinx, Inc.");
740MODULE_DESCRIPTION("Xilinx GPIO driver");
741MODULE_LICENSE("GPL");
742