xref: /linux/drivers/gpio/gpio-zynq.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  * Xilinx Zynq GPIO device driver
3  *
4  * Copyright (C) 2009 - 2014 Xilinx, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify it under
7  * the terms of the GNU General Public License as published by the Free Software
8  * Foundation; either version 2 of the License, or (at your option) any later
9  * version.
10  */
11 
12 #include <linux/bitops.h>
13 #include <linux/clk.h>
14 #include <linux/gpio/driver.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_runtime.h>
21 
22 #define DRIVER_NAME "zynq-gpio"
23 
24 /* Maximum banks */
25 #define ZYNQ_GPIO_MAX_BANK	4
26 
27 #define ZYNQ_GPIO_BANK0_NGPIO	32
28 #define ZYNQ_GPIO_BANK1_NGPIO	22
29 #define ZYNQ_GPIO_BANK2_NGPIO	32
30 #define ZYNQ_GPIO_BANK3_NGPIO	32
31 
32 #define ZYNQ_GPIO_NR_GPIOS	(ZYNQ_GPIO_BANK0_NGPIO + \
33 				 ZYNQ_GPIO_BANK1_NGPIO + \
34 				 ZYNQ_GPIO_BANK2_NGPIO + \
35 				 ZYNQ_GPIO_BANK3_NGPIO)
36 
37 #define ZYNQ_GPIO_BANK0_PIN_MIN	0
38 #define ZYNQ_GPIO_BANK0_PIN_MAX	(ZYNQ_GPIO_BANK0_PIN_MIN + \
39 					ZYNQ_GPIO_BANK0_NGPIO - 1)
40 #define ZYNQ_GPIO_BANK1_PIN_MIN	(ZYNQ_GPIO_BANK0_PIN_MAX + 1)
41 #define ZYNQ_GPIO_BANK1_PIN_MAX	(ZYNQ_GPIO_BANK1_PIN_MIN + \
42 					ZYNQ_GPIO_BANK1_NGPIO - 1)
43 #define ZYNQ_GPIO_BANK2_PIN_MIN	(ZYNQ_GPIO_BANK1_PIN_MAX + 1)
44 #define ZYNQ_GPIO_BANK2_PIN_MAX	(ZYNQ_GPIO_BANK2_PIN_MIN + \
45 					ZYNQ_GPIO_BANK2_NGPIO - 1)
46 #define ZYNQ_GPIO_BANK3_PIN_MIN	(ZYNQ_GPIO_BANK2_PIN_MAX + 1)
47 #define ZYNQ_GPIO_BANK3_PIN_MAX	(ZYNQ_GPIO_BANK3_PIN_MIN + \
48 					ZYNQ_GPIO_BANK3_NGPIO - 1)
49 
50 
51 /* Register offsets for the GPIO device */
52 /* LSW Mask & Data -WO */
53 #define ZYNQ_GPIO_DATA_LSW_OFFSET(BANK)	(0x000 + (8 * BANK))
54 /* MSW Mask & Data -WO */
55 #define ZYNQ_GPIO_DATA_MSW_OFFSET(BANK)	(0x004 + (8 * BANK))
56 /* Data Register-RW */
57 #define ZYNQ_GPIO_DATA_RO_OFFSET(BANK)	(0x060 + (4 * BANK))
58 /* Direction mode reg-RW */
59 #define ZYNQ_GPIO_DIRM_OFFSET(BANK)	(0x204 + (0x40 * BANK))
60 /* Output enable reg-RW */
61 #define ZYNQ_GPIO_OUTEN_OFFSET(BANK)	(0x208 + (0x40 * BANK))
62 /* Interrupt mask reg-RO */
63 #define ZYNQ_GPIO_INTMASK_OFFSET(BANK)	(0x20C + (0x40 * BANK))
64 /* Interrupt enable reg-WO */
65 #define ZYNQ_GPIO_INTEN_OFFSET(BANK)	(0x210 + (0x40 * BANK))
66 /* Interrupt disable reg-WO */
67 #define ZYNQ_GPIO_INTDIS_OFFSET(BANK)	(0x214 + (0x40 * BANK))
68 /* Interrupt status reg-RO */
69 #define ZYNQ_GPIO_INTSTS_OFFSET(BANK)	(0x218 + (0x40 * BANK))
70 /* Interrupt type reg-RW */
71 #define ZYNQ_GPIO_INTTYPE_OFFSET(BANK)	(0x21C + (0x40 * BANK))
72 /* Interrupt polarity reg-RW */
73 #define ZYNQ_GPIO_INTPOL_OFFSET(BANK)	(0x220 + (0x40 * BANK))
74 /* Interrupt on any, reg-RW */
75 #define ZYNQ_GPIO_INTANY_OFFSET(BANK)	(0x224 + (0x40 * BANK))
76 
77 /* Disable all interrupts mask */
78 #define ZYNQ_GPIO_IXR_DISABLE_ALL	0xFFFFFFFF
79 
80 /* Mid pin number of a bank */
81 #define ZYNQ_GPIO_MID_PIN_NUM 16
82 
83 /* GPIO upper 16 bit mask */
84 #define ZYNQ_GPIO_UPPER_MASK 0xFFFF0000
85 
86 /**
87  * struct zynq_gpio - gpio device private data structure
88  * @chip:	instance of the gpio_chip
89  * @base_addr:	base address of the GPIO device
90  * @clk:	clock resource for this controller
91  * @irq:	interrupt for the GPIO device
92  */
93 struct zynq_gpio {
94 	struct gpio_chip chip;
95 	void __iomem *base_addr;
96 	struct clk *clk;
97 	int irq;
98 };
99 
100 static struct irq_chip zynq_gpio_level_irqchip;
101 static struct irq_chip zynq_gpio_edge_irqchip;
102 /**
103  * zynq_gpio_get_bank_pin - Get the bank number and pin number within that bank
104  * for a given pin in the GPIO device
105  * @pin_num:	gpio pin number within the device
106  * @bank_num:	an output parameter used to return the bank number of the gpio
107  *		pin
108  * @bank_pin_num: an output parameter used to return pin number within a bank
109  *		  for the given gpio pin
110  *
111  * Returns the bank number and pin offset within the bank.
112  */
113 static inline void zynq_gpio_get_bank_pin(unsigned int pin_num,
114 					  unsigned int *bank_num,
115 					  unsigned int *bank_pin_num)
116 {
117 	switch (pin_num) {
118 	case ZYNQ_GPIO_BANK0_PIN_MIN ... ZYNQ_GPIO_BANK0_PIN_MAX:
119 		*bank_num = 0;
120 		*bank_pin_num = pin_num;
121 		break;
122 	case ZYNQ_GPIO_BANK1_PIN_MIN ... ZYNQ_GPIO_BANK1_PIN_MAX:
123 		*bank_num = 1;
124 		*bank_pin_num = pin_num - ZYNQ_GPIO_BANK1_PIN_MIN;
125 		break;
126 	case ZYNQ_GPIO_BANK2_PIN_MIN ... ZYNQ_GPIO_BANK2_PIN_MAX:
127 		*bank_num = 2;
128 		*bank_pin_num = pin_num - ZYNQ_GPIO_BANK2_PIN_MIN;
129 		break;
130 	case ZYNQ_GPIO_BANK3_PIN_MIN ... ZYNQ_GPIO_BANK3_PIN_MAX:
131 		*bank_num = 3;
132 		*bank_pin_num = pin_num - ZYNQ_GPIO_BANK3_PIN_MIN;
133 		break;
134 	default:
135 		WARN(true, "invalid GPIO pin number: %u", pin_num);
136 		*bank_num = 0;
137 		*bank_pin_num = 0;
138 		break;
139 	}
140 }
141 
142 static const unsigned int zynq_gpio_bank_offset[] = {
143 	ZYNQ_GPIO_BANK0_PIN_MIN,
144 	ZYNQ_GPIO_BANK1_PIN_MIN,
145 	ZYNQ_GPIO_BANK2_PIN_MIN,
146 	ZYNQ_GPIO_BANK3_PIN_MIN,
147 };
148 
149 /**
150  * zynq_gpio_get_value - Get the state of the specified pin of GPIO device
151  * @chip:	gpio_chip instance to be worked on
152  * @pin:	gpio pin number within the device
153  *
154  * This function reads the state of the specified pin of the GPIO device.
155  *
156  * Return: 0 if the pin is low, 1 if pin is high.
157  */
158 static int zynq_gpio_get_value(struct gpio_chip *chip, unsigned int pin)
159 {
160 	u32 data;
161 	unsigned int bank_num, bank_pin_num;
162 	struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip);
163 
164 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num);
165 
166 	data = readl_relaxed(gpio->base_addr +
167 			     ZYNQ_GPIO_DATA_RO_OFFSET(bank_num));
168 
169 	return (data >> bank_pin_num) & 1;
170 }
171 
172 /**
173  * zynq_gpio_set_value - Modify the state of the pin with specified value
174  * @chip:	gpio_chip instance to be worked on
175  * @pin:	gpio pin number within the device
176  * @state:	value used to modify the state of the specified pin
177  *
178  * This function calculates the register offset (i.e to lower 16 bits or
179  * upper 16 bits) based on the given pin number and sets the state of a
180  * gpio pin to the specified value. The state is either 0 or non-zero.
181  */
182 static void zynq_gpio_set_value(struct gpio_chip *chip, unsigned int pin,
183 				int state)
184 {
185 	unsigned int reg_offset, bank_num, bank_pin_num;
186 	struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip);
187 
188 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num);
189 
190 	if (bank_pin_num >= ZYNQ_GPIO_MID_PIN_NUM) {
191 		/* only 16 data bits in bit maskable reg */
192 		bank_pin_num -= ZYNQ_GPIO_MID_PIN_NUM;
193 		reg_offset = ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num);
194 	} else {
195 		reg_offset = ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num);
196 	}
197 
198 	/*
199 	 * get the 32 bit value to be written to the mask/data register where
200 	 * the upper 16 bits is the mask and lower 16 bits is the data
201 	 */
202 	state = !!state;
203 	state = ~(1 << (bank_pin_num + ZYNQ_GPIO_MID_PIN_NUM)) &
204 		((state << bank_pin_num) | ZYNQ_GPIO_UPPER_MASK);
205 
206 	writel_relaxed(state, gpio->base_addr + reg_offset);
207 }
208 
209 /**
210  * zynq_gpio_dir_in - Set the direction of the specified GPIO pin as input
211  * @chip:	gpio_chip instance to be worked on
212  * @pin:	gpio pin number within the device
213  *
214  * This function uses the read-modify-write sequence to set the direction of
215  * the gpio pin as input.
216  *
217  * Return: 0 always
218  */
219 static int zynq_gpio_dir_in(struct gpio_chip *chip, unsigned int pin)
220 {
221 	u32 reg;
222 	unsigned int bank_num, bank_pin_num;
223 	struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip);
224 
225 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num);
226 
227 	/* bank 0 pins 7 and 8 are special and cannot be used as inputs */
228 	if (bank_num == 0 && (bank_pin_num == 7 || bank_pin_num == 8))
229 		return -EINVAL;
230 
231 	/* clear the bit in direction mode reg to set the pin as input */
232 	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
233 	reg &= ~BIT(bank_pin_num);
234 	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
235 
236 	return 0;
237 }
238 
239 /**
240  * zynq_gpio_dir_out - Set the direction of the specified GPIO pin as output
241  * @chip:	gpio_chip instance to be worked on
242  * @pin:	gpio pin number within the device
243  * @state:	value to be written to specified pin
244  *
245  * This function sets the direction of specified GPIO pin as output, configures
246  * the Output Enable register for the pin and uses zynq_gpio_set to set
247  * the state of the pin to the value specified.
248  *
249  * Return: 0 always
250  */
251 static int zynq_gpio_dir_out(struct gpio_chip *chip, unsigned int pin,
252 			     int state)
253 {
254 	u32 reg;
255 	unsigned int bank_num, bank_pin_num;
256 	struct zynq_gpio *gpio = container_of(chip, struct zynq_gpio, chip);
257 
258 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num);
259 
260 	/* set the GPIO pin as output */
261 	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
262 	reg |= BIT(bank_pin_num);
263 	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
264 
265 	/* configure the output enable reg for the pin */
266 	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num));
267 	reg |= BIT(bank_pin_num);
268 	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num));
269 
270 	/* set the state of the pin */
271 	zynq_gpio_set_value(chip, pin, state);
272 	return 0;
273 }
274 
275 /**
276  * zynq_gpio_irq_mask - Disable the interrupts for a gpio pin
277  * @irq_data:	per irq and chip data passed down to chip functions
278  *
279  * This function calculates gpio pin number from irq number and sets the
280  * bit in the Interrupt Disable register of the corresponding bank to disable
281  * interrupts for that pin.
282  */
283 static void zynq_gpio_irq_mask(struct irq_data *irq_data)
284 {
285 	unsigned int device_pin_num, bank_num, bank_pin_num;
286 	struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data);
287 
288 	device_pin_num = irq_data->hwirq;
289 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num);
290 	writel_relaxed(BIT(bank_pin_num),
291 		       gpio->base_addr + ZYNQ_GPIO_INTDIS_OFFSET(bank_num));
292 }
293 
294 /**
295  * zynq_gpio_irq_unmask - Enable the interrupts for a gpio pin
296  * @irq_data:	irq data containing irq number of gpio pin for the interrupt
297  *		to enable
298  *
299  * This function calculates the gpio pin number from irq number and sets the
300  * bit in the Interrupt Enable register of the corresponding bank to enable
301  * interrupts for that pin.
302  */
303 static void zynq_gpio_irq_unmask(struct irq_data *irq_data)
304 {
305 	unsigned int device_pin_num, bank_num, bank_pin_num;
306 	struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data);
307 
308 	device_pin_num = irq_data->hwirq;
309 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num);
310 	writel_relaxed(BIT(bank_pin_num),
311 		       gpio->base_addr + ZYNQ_GPIO_INTEN_OFFSET(bank_num));
312 }
313 
314 /**
315  * zynq_gpio_irq_ack - Acknowledge the interrupt of a gpio pin
316  * @irq_data:	irq data containing irq number of gpio pin for the interrupt
317  *		to ack
318  *
319  * This function calculates gpio pin number from irq number and sets the bit
320  * in the Interrupt Status Register of the corresponding bank, to ACK the irq.
321  */
322 static void zynq_gpio_irq_ack(struct irq_data *irq_data)
323 {
324 	unsigned int device_pin_num, bank_num, bank_pin_num;
325 	struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data);
326 
327 	device_pin_num = irq_data->hwirq;
328 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num);
329 	writel_relaxed(BIT(bank_pin_num),
330 		       gpio->base_addr + ZYNQ_GPIO_INTSTS_OFFSET(bank_num));
331 }
332 
333 /**
334  * zynq_gpio_irq_enable - Enable the interrupts for a gpio pin
335  * @irq_data:	irq data containing irq number of gpio pin for the interrupt
336  *		to enable
337  *
338  * Clears the INTSTS bit and unmasks the given interrrupt.
339  */
340 static void zynq_gpio_irq_enable(struct irq_data *irq_data)
341 {
342 	/*
343 	 * The Zynq GPIO controller does not disable interrupt detection when
344 	 * the interrupt is masked and only disables the propagation of the
345 	 * interrupt. This means when the controller detects an interrupt
346 	 * condition while the interrupt is logically disabled it will propagate
347 	 * that interrupt event once the interrupt is enabled. This will cause
348 	 * the interrupt consumer to see spurious interrupts to prevent this
349 	 * first make sure that the interrupt is not asserted and then enable
350 	 * it.
351 	 */
352 	zynq_gpio_irq_ack(irq_data);
353 	zynq_gpio_irq_unmask(irq_data);
354 }
355 
356 /**
357  * zynq_gpio_set_irq_type - Set the irq type for a gpio pin
358  * @irq_data:	irq data containing irq number of gpio pin
359  * @type:	interrupt type that is to be set for the gpio pin
360  *
361  * This function gets the gpio pin number and its bank from the gpio pin number
362  * and configures the INT_TYPE, INT_POLARITY and INT_ANY registers.
363  *
364  * Return: 0, negative error otherwise.
365  * TYPE-EDGE_RISING,  INT_TYPE - 1, INT_POLARITY - 1,  INT_ANY - 0;
366  * TYPE-EDGE_FALLING, INT_TYPE - 1, INT_POLARITY - 0,  INT_ANY - 0;
367  * TYPE-EDGE_BOTH,    INT_TYPE - 1, INT_POLARITY - NA, INT_ANY - 1;
368  * TYPE-LEVEL_HIGH,   INT_TYPE - 0, INT_POLARITY - 1,  INT_ANY - NA;
369  * TYPE-LEVEL_LOW,    INT_TYPE - 0, INT_POLARITY - 0,  INT_ANY - NA
370  */
371 static int zynq_gpio_set_irq_type(struct irq_data *irq_data, unsigned int type)
372 {
373 	u32 int_type, int_pol, int_any;
374 	unsigned int device_pin_num, bank_num, bank_pin_num;
375 	struct zynq_gpio *gpio = irq_data_get_irq_chip_data(irq_data);
376 
377 	device_pin_num = irq_data->hwirq;
378 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num);
379 
380 	int_type = readl_relaxed(gpio->base_addr +
381 				 ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
382 	int_pol = readl_relaxed(gpio->base_addr +
383 				ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
384 	int_any = readl_relaxed(gpio->base_addr +
385 				ZYNQ_GPIO_INTANY_OFFSET(bank_num));
386 
387 	/*
388 	 * based on the type requested, configure the INT_TYPE, INT_POLARITY
389 	 * and INT_ANY registers
390 	 */
391 	switch (type) {
392 	case IRQ_TYPE_EDGE_RISING:
393 		int_type |= BIT(bank_pin_num);
394 		int_pol |= BIT(bank_pin_num);
395 		int_any &= ~BIT(bank_pin_num);
396 		break;
397 	case IRQ_TYPE_EDGE_FALLING:
398 		int_type |= BIT(bank_pin_num);
399 		int_pol &= ~BIT(bank_pin_num);
400 		int_any &= ~BIT(bank_pin_num);
401 		break;
402 	case IRQ_TYPE_EDGE_BOTH:
403 		int_type |= BIT(bank_pin_num);
404 		int_any |= BIT(bank_pin_num);
405 		break;
406 	case IRQ_TYPE_LEVEL_HIGH:
407 		int_type &= ~BIT(bank_pin_num);
408 		int_pol |= BIT(bank_pin_num);
409 		break;
410 	case IRQ_TYPE_LEVEL_LOW:
411 		int_type &= ~BIT(bank_pin_num);
412 		int_pol &= ~BIT(bank_pin_num);
413 		break;
414 	default:
415 		return -EINVAL;
416 	}
417 
418 	writel_relaxed(int_type,
419 		       gpio->base_addr + ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
420 	writel_relaxed(int_pol,
421 		       gpio->base_addr + ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
422 	writel_relaxed(int_any,
423 		       gpio->base_addr + ZYNQ_GPIO_INTANY_OFFSET(bank_num));
424 
425 	if (type & IRQ_TYPE_LEVEL_MASK) {
426 		__irq_set_chip_handler_name_locked(irq_data->irq,
427 			&zynq_gpio_level_irqchip, handle_fasteoi_irq, NULL);
428 	} else {
429 		__irq_set_chip_handler_name_locked(irq_data->irq,
430 			&zynq_gpio_edge_irqchip, handle_level_irq, NULL);
431 	}
432 
433 	return 0;
434 }
435 
436 static int zynq_gpio_set_wake(struct irq_data *data, unsigned int on)
437 {
438 	struct zynq_gpio *gpio = irq_data_get_irq_chip_data(data);
439 
440 	irq_set_irq_wake(gpio->irq, on);
441 
442 	return 0;
443 }
444 
445 /* irq chip descriptor */
446 static struct irq_chip zynq_gpio_level_irqchip = {
447 	.name		= DRIVER_NAME,
448 	.irq_enable	= zynq_gpio_irq_enable,
449 	.irq_eoi	= zynq_gpio_irq_ack,
450 	.irq_mask	= zynq_gpio_irq_mask,
451 	.irq_unmask	= zynq_gpio_irq_unmask,
452 	.irq_set_type	= zynq_gpio_set_irq_type,
453 	.irq_set_wake	= zynq_gpio_set_wake,
454 	.flags		= IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED |
455 			  IRQCHIP_MASK_ON_SUSPEND,
456 };
457 
458 static struct irq_chip zynq_gpio_edge_irqchip = {
459 	.name		= DRIVER_NAME,
460 	.irq_enable	= zynq_gpio_irq_enable,
461 	.irq_ack	= zynq_gpio_irq_ack,
462 	.irq_mask	= zynq_gpio_irq_mask,
463 	.irq_unmask	= zynq_gpio_irq_unmask,
464 	.irq_set_type	= zynq_gpio_set_irq_type,
465 	.irq_set_wake	= zynq_gpio_set_wake,
466 	.flags		= IRQCHIP_MASK_ON_SUSPEND,
467 };
468 
469 static void zynq_gpio_handle_bank_irq(struct zynq_gpio *gpio,
470 				      unsigned int bank_num,
471 				      unsigned long pending)
472 {
473 	unsigned int bank_offset = zynq_gpio_bank_offset[bank_num];
474 	struct irq_domain *irqdomain = gpio->chip.irqdomain;
475 	int offset;
476 
477 	if (!pending)
478 		return;
479 
480 	for_each_set_bit(offset, &pending, 32) {
481 		unsigned int gpio_irq;
482 
483 		gpio_irq = irq_find_mapping(irqdomain, offset + bank_offset);
484 		generic_handle_irq(gpio_irq);
485 	}
486 }
487 
488 /**
489  * zynq_gpio_irqhandler - IRQ handler for the gpio banks of a gpio device
490  * @irq:	irq number of the gpio bank where interrupt has occurred
491  * @desc:	irq descriptor instance of the 'irq'
492  *
493  * This function reads the Interrupt Status Register of each bank to get the
494  * gpio pin number which has triggered an interrupt. It then acks the triggered
495  * interrupt and calls the pin specific handler set by the higher layer
496  * application for that pin.
497  * Note: A bug is reported if no handler is set for the gpio pin.
498  */
499 static void zynq_gpio_irqhandler(unsigned int irq, struct irq_desc *desc)
500 {
501 	u32 int_sts, int_enb;
502 	unsigned int bank_num;
503 	struct zynq_gpio *gpio = irq_get_handler_data(irq);
504 	struct irq_chip *irqchip = irq_desc_get_chip(desc);
505 
506 	chained_irq_enter(irqchip, desc);
507 
508 	for (bank_num = 0; bank_num < ZYNQ_GPIO_MAX_BANK; bank_num++) {
509 		int_sts = readl_relaxed(gpio->base_addr +
510 					ZYNQ_GPIO_INTSTS_OFFSET(bank_num));
511 		int_enb = readl_relaxed(gpio->base_addr +
512 					ZYNQ_GPIO_INTMASK_OFFSET(bank_num));
513 		zynq_gpio_handle_bank_irq(gpio, bank_num, int_sts & ~int_enb);
514 	}
515 
516 	chained_irq_exit(irqchip, desc);
517 }
518 
519 static int __maybe_unused zynq_gpio_suspend(struct device *dev)
520 {
521 	struct platform_device *pdev = to_platform_device(dev);
522 	int irq = platform_get_irq(pdev, 0);
523 	struct irq_data *data = irq_get_irq_data(irq);
524 
525 	if (!irqd_is_wakeup_set(data))
526 		return pm_runtime_force_suspend(dev);
527 
528 	return 0;
529 }
530 
531 static int __maybe_unused zynq_gpio_resume(struct device *dev)
532 {
533 	struct platform_device *pdev = to_platform_device(dev);
534 	int irq = platform_get_irq(pdev, 0);
535 	struct irq_data *data = irq_get_irq_data(irq);
536 
537 	if (!irqd_is_wakeup_set(data))
538 		return pm_runtime_force_resume(dev);
539 
540 	return 0;
541 }
542 
543 static int __maybe_unused zynq_gpio_runtime_suspend(struct device *dev)
544 {
545 	struct platform_device *pdev = to_platform_device(dev);
546 	struct zynq_gpio *gpio = platform_get_drvdata(pdev);
547 
548 	clk_disable_unprepare(gpio->clk);
549 
550 	return 0;
551 }
552 
553 static int __maybe_unused zynq_gpio_runtime_resume(struct device *dev)
554 {
555 	struct platform_device *pdev = to_platform_device(dev);
556 	struct zynq_gpio *gpio = platform_get_drvdata(pdev);
557 
558 	return clk_prepare_enable(gpio->clk);
559 }
560 
561 static int zynq_gpio_request(struct gpio_chip *chip, unsigned offset)
562 {
563 	int ret;
564 
565 	ret = pm_runtime_get_sync(chip->dev);
566 
567 	/*
568 	 * If the device is already active pm_runtime_get() will return 1 on
569 	 * success, but gpio_request still needs to return 0.
570 	 */
571 	return ret < 0 ? ret : 0;
572 }
573 
574 static void zynq_gpio_free(struct gpio_chip *chip, unsigned offset)
575 {
576 	pm_runtime_put(chip->dev);
577 }
578 
579 static const struct dev_pm_ops zynq_gpio_dev_pm_ops = {
580 	SET_SYSTEM_SLEEP_PM_OPS(zynq_gpio_suspend, zynq_gpio_resume)
581 	SET_RUNTIME_PM_OPS(zynq_gpio_runtime_suspend,
582 			zynq_gpio_runtime_resume, NULL)
583 };
584 
585 /**
586  * zynq_gpio_probe - Initialization method for a zynq_gpio device
587  * @pdev:	platform device instance
588  *
589  * This function allocates memory resources for the gpio device and registers
590  * all the banks of the device. It will also set up interrupts for the gpio
591  * pins.
592  * Note: Interrupts are disabled for all the banks during initialization.
593  *
594  * Return: 0 on success, negative error otherwise.
595  */
596 static int zynq_gpio_probe(struct platform_device *pdev)
597 {
598 	int ret, bank_num;
599 	struct zynq_gpio *gpio;
600 	struct gpio_chip *chip;
601 	struct resource *res;
602 
603 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
604 	if (!gpio)
605 		return -ENOMEM;
606 
607 	platform_set_drvdata(pdev, gpio);
608 
609 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
610 	gpio->base_addr = devm_ioremap_resource(&pdev->dev, res);
611 	if (IS_ERR(gpio->base_addr))
612 		return PTR_ERR(gpio->base_addr);
613 
614 	gpio->irq = platform_get_irq(pdev, 0);
615 	if (gpio->irq < 0) {
616 		dev_err(&pdev->dev, "invalid IRQ\n");
617 		return gpio->irq;
618 	}
619 
620 	/* configure the gpio chip */
621 	chip = &gpio->chip;
622 	chip->label = "zynq_gpio";
623 	chip->owner = THIS_MODULE;
624 	chip->dev = &pdev->dev;
625 	chip->get = zynq_gpio_get_value;
626 	chip->set = zynq_gpio_set_value;
627 	chip->request = zynq_gpio_request;
628 	chip->free = zynq_gpio_free;
629 	chip->direction_input = zynq_gpio_dir_in;
630 	chip->direction_output = zynq_gpio_dir_out;
631 	chip->base = -1;
632 	chip->ngpio = ZYNQ_GPIO_NR_GPIOS;
633 
634 	/* Enable GPIO clock */
635 	gpio->clk = devm_clk_get(&pdev->dev, NULL);
636 	if (IS_ERR(gpio->clk)) {
637 		dev_err(&pdev->dev, "input clock not found.\n");
638 		return PTR_ERR(gpio->clk);
639 	}
640 	ret = clk_prepare_enable(gpio->clk);
641 	if (ret) {
642 		dev_err(&pdev->dev, "Unable to enable clock.\n");
643 		return ret;
644 	}
645 
646 	/* report a bug if gpio chip registration fails */
647 	ret = gpiochip_add(chip);
648 	if (ret) {
649 		dev_err(&pdev->dev, "Failed to add gpio chip\n");
650 		goto err_disable_clk;
651 	}
652 
653 	/* disable interrupts for all banks */
654 	for (bank_num = 0; bank_num < ZYNQ_GPIO_MAX_BANK; bank_num++)
655 		writel_relaxed(ZYNQ_GPIO_IXR_DISABLE_ALL, gpio->base_addr +
656 			       ZYNQ_GPIO_INTDIS_OFFSET(bank_num));
657 
658 	ret = gpiochip_irqchip_add(chip, &zynq_gpio_edge_irqchip, 0,
659 				   handle_level_irq, IRQ_TYPE_NONE);
660 	if (ret) {
661 		dev_err(&pdev->dev, "Failed to add irq chip\n");
662 		goto err_rm_gpiochip;
663 	}
664 
665 	gpiochip_set_chained_irqchip(chip, &zynq_gpio_edge_irqchip, gpio->irq,
666 				     zynq_gpio_irqhandler);
667 
668 	pm_runtime_set_active(&pdev->dev);
669 	pm_runtime_enable(&pdev->dev);
670 
671 	return 0;
672 
673 err_rm_gpiochip:
674 	gpiochip_remove(chip);
675 err_disable_clk:
676 	clk_disable_unprepare(gpio->clk);
677 
678 	return ret;
679 }
680 
681 /**
682  * zynq_gpio_remove - Driver removal function
683  * @pdev:	platform device instance
684  *
685  * Return: 0 always
686  */
687 static int zynq_gpio_remove(struct platform_device *pdev)
688 {
689 	struct zynq_gpio *gpio = platform_get_drvdata(pdev);
690 
691 	pm_runtime_get_sync(&pdev->dev);
692 	gpiochip_remove(&gpio->chip);
693 	clk_disable_unprepare(gpio->clk);
694 	device_set_wakeup_capable(&pdev->dev, 0);
695 	return 0;
696 }
697 
698 static struct of_device_id zynq_gpio_of_match[] = {
699 	{ .compatible = "xlnx,zynq-gpio-1.0", },
700 	{ /* end of table */ }
701 };
702 MODULE_DEVICE_TABLE(of, zynq_gpio_of_match);
703 
704 static struct platform_driver zynq_gpio_driver = {
705 	.driver	= {
706 		.name = DRIVER_NAME,
707 		.pm = &zynq_gpio_dev_pm_ops,
708 		.of_match_table = zynq_gpio_of_match,
709 	},
710 	.probe = zynq_gpio_probe,
711 	.remove = zynq_gpio_remove,
712 };
713 
714 /**
715  * zynq_gpio_init - Initial driver registration call
716  *
717  * Return: value from platform_driver_register
718  */
719 static int __init zynq_gpio_init(void)
720 {
721 	return platform_driver_register(&zynq_gpio_driver);
722 }
723 postcore_initcall(zynq_gpio_init);
724 
725 MODULE_AUTHOR("Xilinx Inc.");
726 MODULE_DESCRIPTION("Zynq GPIO driver");
727 MODULE_LICENSE("GPL");
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