xref: /linux/drivers/gpio/gpio-zynq.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Xilinx Zynq GPIO device driver
4  *
5  * Copyright (C) 2009 - 2014 Xilinx, Inc.
6  */
7 
8 #include <linux/bitops.h>
9 #include <linux/clk.h>
10 #include <linux/gpio/driver.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/spinlock.h>
14 #include <linux/io.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/of.h>
19 
20 #define DRIVER_NAME "zynq-gpio"
21 
22 /* Maximum banks */
23 #define ZYNQ_GPIO_MAX_BANK	4
24 #define ZYNQMP_GPIO_MAX_BANK	6
25 #define VERSAL_GPIO_MAX_BANK	4
26 #define PMC_GPIO_MAX_BANK	5
27 #define VERSAL_UNUSED_BANKS	2
28 
29 #define ZYNQ_GPIO_BANK0_NGPIO	32
30 #define ZYNQ_GPIO_BANK1_NGPIO	22
31 #define ZYNQ_GPIO_BANK2_NGPIO	32
32 #define ZYNQ_GPIO_BANK3_NGPIO	32
33 
34 #define ZYNQMP_GPIO_BANK0_NGPIO 26
35 #define ZYNQMP_GPIO_BANK1_NGPIO 26
36 #define ZYNQMP_GPIO_BANK2_NGPIO 26
37 #define ZYNQMP_GPIO_BANK3_NGPIO 32
38 #define ZYNQMP_GPIO_BANK4_NGPIO 32
39 #define ZYNQMP_GPIO_BANK5_NGPIO 32
40 
41 #define	ZYNQ_GPIO_NR_GPIOS	118
42 #define	ZYNQMP_GPIO_NR_GPIOS	174
43 
44 #define ZYNQ_GPIO_BANK0_PIN_MIN(str)	0
45 #define ZYNQ_GPIO_BANK0_PIN_MAX(str)	(ZYNQ_GPIO_BANK0_PIN_MIN(str) + \
46 					ZYNQ##str##_GPIO_BANK0_NGPIO - 1)
47 #define ZYNQ_GPIO_BANK1_PIN_MIN(str)	(ZYNQ_GPIO_BANK0_PIN_MAX(str) + 1)
48 #define ZYNQ_GPIO_BANK1_PIN_MAX(str)	(ZYNQ_GPIO_BANK1_PIN_MIN(str) + \
49 					ZYNQ##str##_GPIO_BANK1_NGPIO - 1)
50 #define ZYNQ_GPIO_BANK2_PIN_MIN(str)	(ZYNQ_GPIO_BANK1_PIN_MAX(str) + 1)
51 #define ZYNQ_GPIO_BANK2_PIN_MAX(str)	(ZYNQ_GPIO_BANK2_PIN_MIN(str) + \
52 					ZYNQ##str##_GPIO_BANK2_NGPIO - 1)
53 #define ZYNQ_GPIO_BANK3_PIN_MIN(str)	(ZYNQ_GPIO_BANK2_PIN_MAX(str) + 1)
54 #define ZYNQ_GPIO_BANK3_PIN_MAX(str)	(ZYNQ_GPIO_BANK3_PIN_MIN(str) + \
55 					ZYNQ##str##_GPIO_BANK3_NGPIO - 1)
56 #define ZYNQ_GPIO_BANK4_PIN_MIN(str)	(ZYNQ_GPIO_BANK3_PIN_MAX(str) + 1)
57 #define ZYNQ_GPIO_BANK4_PIN_MAX(str)	(ZYNQ_GPIO_BANK4_PIN_MIN(str) + \
58 					ZYNQ##str##_GPIO_BANK4_NGPIO - 1)
59 #define ZYNQ_GPIO_BANK5_PIN_MIN(str)	(ZYNQ_GPIO_BANK4_PIN_MAX(str) + 1)
60 #define ZYNQ_GPIO_BANK5_PIN_MAX(str)	(ZYNQ_GPIO_BANK5_PIN_MIN(str) + \
61 					ZYNQ##str##_GPIO_BANK5_NGPIO - 1)
62 
63 /* Register offsets for the GPIO device */
64 /* LSW Mask & Data -WO */
65 #define ZYNQ_GPIO_DATA_LSW_OFFSET(BANK)	(0x000 + (8 * BANK))
66 /* MSW Mask & Data -WO */
67 #define ZYNQ_GPIO_DATA_MSW_OFFSET(BANK)	(0x004 + (8 * BANK))
68 /* Data Register-RW */
69 #define ZYNQ_GPIO_DATA_OFFSET(BANK)	(0x040 + (4 * BANK))
70 #define ZYNQ_GPIO_DATA_RO_OFFSET(BANK)	(0x060 + (4 * BANK))
71 /* Direction mode reg-RW */
72 #define ZYNQ_GPIO_DIRM_OFFSET(BANK)	(0x204 + (0x40 * BANK))
73 /* Output enable reg-RW */
74 #define ZYNQ_GPIO_OUTEN_OFFSET(BANK)	(0x208 + (0x40 * BANK))
75 /* Interrupt mask reg-RO */
76 #define ZYNQ_GPIO_INTMASK_OFFSET(BANK)	(0x20C + (0x40 * BANK))
77 /* Interrupt enable reg-WO */
78 #define ZYNQ_GPIO_INTEN_OFFSET(BANK)	(0x210 + (0x40 * BANK))
79 /* Interrupt disable reg-WO */
80 #define ZYNQ_GPIO_INTDIS_OFFSET(BANK)	(0x214 + (0x40 * BANK))
81 /* Interrupt status reg-RO */
82 #define ZYNQ_GPIO_INTSTS_OFFSET(BANK)	(0x218 + (0x40 * BANK))
83 /* Interrupt type reg-RW */
84 #define ZYNQ_GPIO_INTTYPE_OFFSET(BANK)	(0x21C + (0x40 * BANK))
85 /* Interrupt polarity reg-RW */
86 #define ZYNQ_GPIO_INTPOL_OFFSET(BANK)	(0x220 + (0x40 * BANK))
87 /* Interrupt on any, reg-RW */
88 #define ZYNQ_GPIO_INTANY_OFFSET(BANK)	(0x224 + (0x40 * BANK))
89 
90 /* Disable all interrupts mask */
91 #define ZYNQ_GPIO_IXR_DISABLE_ALL	0xFFFFFFFF
92 
93 /* Mid pin number of a bank */
94 #define ZYNQ_GPIO_MID_PIN_NUM 16
95 
96 /* GPIO upper 16 bit mask */
97 #define ZYNQ_GPIO_UPPER_MASK 0xFFFF0000
98 
99 /* set to differentiate zynq from zynqmp, 0=zynqmp, 1=zynq */
100 #define ZYNQ_GPIO_QUIRK_IS_ZYNQ	BIT(0)
101 #define GPIO_QUIRK_DATA_RO_BUG	BIT(1)
102 #define GPIO_QUIRK_VERSAL	BIT(2)
103 
104 struct gpio_regs {
105 	u32 datamsw[ZYNQMP_GPIO_MAX_BANK];
106 	u32 datalsw[ZYNQMP_GPIO_MAX_BANK];
107 	u32 dirm[ZYNQMP_GPIO_MAX_BANK];
108 	u32 outen[ZYNQMP_GPIO_MAX_BANK];
109 	u32 int_en[ZYNQMP_GPIO_MAX_BANK];
110 	u32 int_dis[ZYNQMP_GPIO_MAX_BANK];
111 	u32 int_type[ZYNQMP_GPIO_MAX_BANK];
112 	u32 int_polarity[ZYNQMP_GPIO_MAX_BANK];
113 	u32 int_any[ZYNQMP_GPIO_MAX_BANK];
114 };
115 
116 /**
117  * struct zynq_gpio - gpio device private data structure
118  * @chip:	instance of the gpio_chip
119  * @base_addr:	base address of the GPIO device
120  * @clk:	clock resource for this controller
121  * @irq:	interrupt for the GPIO device
122  * @p_data:	pointer to platform data
123  * @context:	context registers
124  * @dirlock:	lock used for direction in/out synchronization
125  */
126 struct zynq_gpio {
127 	struct gpio_chip chip;
128 	void __iomem *base_addr;
129 	struct clk *clk;
130 	int irq;
131 	const struct zynq_platform_data *p_data;
132 	struct gpio_regs context;
133 	spinlock_t dirlock; /* lock */
134 };
135 
136 /**
137  * struct zynq_platform_data -  zynq gpio platform data structure
138  * @label:	string to store in gpio->label
139  * @quirks:	Flags is used to identify the platform
140  * @ngpio:	max number of gpio pins
141  * @max_bank:	maximum number of gpio banks
142  * @bank_min:	this array represents bank's min pin
143  * @bank_max:	this array represents bank's max pin
144  */
145 struct zynq_platform_data {
146 	const char *label;
147 	u32 quirks;
148 	u16 ngpio;
149 	int max_bank;
150 	int bank_min[ZYNQMP_GPIO_MAX_BANK];
151 	int bank_max[ZYNQMP_GPIO_MAX_BANK];
152 };
153 
154 static struct irq_chip zynq_gpio_level_irqchip;
155 static struct irq_chip zynq_gpio_edge_irqchip;
156 
157 /**
158  * zynq_gpio_is_zynq - test if HW is zynq or zynqmp
159  * @gpio:	Pointer to driver data struct
160  *
161  * Return: 0 if zynqmp, 1 if zynq.
162  */
163 static int zynq_gpio_is_zynq(struct zynq_gpio *gpio)
164 {
165 	return !!(gpio->p_data->quirks & ZYNQ_GPIO_QUIRK_IS_ZYNQ);
166 }
167 
168 /**
169  * gpio_data_ro_bug - test if HW bug exists or not
170  * @gpio:       Pointer to driver data struct
171  *
172  * Return: 0 if bug doesnot exist, 1 if bug exists.
173  */
174 static int gpio_data_ro_bug(struct zynq_gpio *gpio)
175 {
176 	return !!(gpio->p_data->quirks & GPIO_QUIRK_DATA_RO_BUG);
177 }
178 
179 /**
180  * zynq_gpio_get_bank_pin - Get the bank number and pin number within that bank
181  * for a given pin in the GPIO device
182  * @pin_num:	gpio pin number within the device
183  * @bank_num:	an output parameter used to return the bank number of the gpio
184  *		pin
185  * @bank_pin_num: an output parameter used to return pin number within a bank
186  *		  for the given gpio pin
187  * @gpio:	gpio device data structure
188  *
189  * Returns the bank number and pin offset within the bank.
190  */
191 static inline void zynq_gpio_get_bank_pin(unsigned int pin_num,
192 					  unsigned int *bank_num,
193 					  unsigned int *bank_pin_num,
194 					  struct zynq_gpio *gpio)
195 {
196 	int bank;
197 
198 	for (bank = 0; bank < gpio->p_data->max_bank; bank++) {
199 		if ((pin_num >= gpio->p_data->bank_min[bank]) &&
200 		    (pin_num <= gpio->p_data->bank_max[bank])) {
201 			*bank_num = bank;
202 			*bank_pin_num = pin_num -
203 					gpio->p_data->bank_min[bank];
204 			return;
205 		}
206 		if (gpio->p_data->quirks & GPIO_QUIRK_VERSAL)
207 			bank = bank + VERSAL_UNUSED_BANKS;
208 	}
209 
210 	/* default */
211 	WARN(true, "invalid GPIO pin number: %u", pin_num);
212 	*bank_num = 0;
213 	*bank_pin_num = 0;
214 }
215 
216 /**
217  * zynq_gpio_get_value - Get the state of the specified pin of GPIO device
218  * @chip:	gpio_chip instance to be worked on
219  * @pin:	gpio pin number within the device
220  *
221  * This function reads the state of the specified pin of the GPIO device.
222  *
223  * Return: 0 if the pin is low, 1 if pin is high.
224  */
225 static int zynq_gpio_get_value(struct gpio_chip *chip, unsigned int pin)
226 {
227 	u32 data;
228 	unsigned int bank_num, bank_pin_num;
229 	struct zynq_gpio *gpio = gpiochip_get_data(chip);
230 
231 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);
232 
233 	if (gpio_data_ro_bug(gpio)) {
234 		if (zynq_gpio_is_zynq(gpio)) {
235 			if (bank_num <= 1) {
236 				data = readl_relaxed(gpio->base_addr +
237 					ZYNQ_GPIO_DATA_RO_OFFSET(bank_num));
238 			} else {
239 				data = readl_relaxed(gpio->base_addr +
240 					ZYNQ_GPIO_DATA_OFFSET(bank_num));
241 			}
242 		} else {
243 			if (bank_num <= 2) {
244 				data = readl_relaxed(gpio->base_addr +
245 					ZYNQ_GPIO_DATA_RO_OFFSET(bank_num));
246 			} else {
247 				data = readl_relaxed(gpio->base_addr +
248 					ZYNQ_GPIO_DATA_OFFSET(bank_num));
249 			}
250 		}
251 	} else {
252 		data = readl_relaxed(gpio->base_addr +
253 			ZYNQ_GPIO_DATA_RO_OFFSET(bank_num));
254 	}
255 	return (data >> bank_pin_num) & 1;
256 }
257 
258 /**
259  * zynq_gpio_set_value - Modify the state of the pin with specified value
260  * @chip:	gpio_chip instance to be worked on
261  * @pin:	gpio pin number within the device
262  * @state:	value used to modify the state of the specified pin
263  *
264  * This function calculates the register offset (i.e to lower 16 bits or
265  * upper 16 bits) based on the given pin number and sets the state of a
266  * gpio pin to the specified value. The state is either 0 or non-zero.
267  */
268 static void zynq_gpio_set_value(struct gpio_chip *chip, unsigned int pin,
269 				int state)
270 {
271 	unsigned int reg_offset, bank_num, bank_pin_num;
272 	struct zynq_gpio *gpio = gpiochip_get_data(chip);
273 
274 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);
275 
276 	if (bank_pin_num >= ZYNQ_GPIO_MID_PIN_NUM) {
277 		/* only 16 data bits in bit maskable reg */
278 		bank_pin_num -= ZYNQ_GPIO_MID_PIN_NUM;
279 		reg_offset = ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num);
280 	} else {
281 		reg_offset = ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num);
282 	}
283 
284 	/*
285 	 * get the 32 bit value to be written to the mask/data register where
286 	 * the upper 16 bits is the mask and lower 16 bits is the data
287 	 */
288 	state = !!state;
289 	state = ~(1 << (bank_pin_num + ZYNQ_GPIO_MID_PIN_NUM)) &
290 		((state << bank_pin_num) | ZYNQ_GPIO_UPPER_MASK);
291 
292 	writel_relaxed(state, gpio->base_addr + reg_offset);
293 }
294 
295 /**
296  * zynq_gpio_dir_in - Set the direction of the specified GPIO pin as input
297  * @chip:	gpio_chip instance to be worked on
298  * @pin:	gpio pin number within the device
299  *
300  * This function uses the read-modify-write sequence to set the direction of
301  * the gpio pin as input.
302  *
303  * Return: 0 always
304  */
305 static int zynq_gpio_dir_in(struct gpio_chip *chip, unsigned int pin)
306 {
307 	u32 reg;
308 	unsigned int bank_num, bank_pin_num;
309 	unsigned long flags;
310 	struct zynq_gpio *gpio = gpiochip_get_data(chip);
311 
312 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);
313 
314 	/*
315 	 * On zynq bank 0 pins 7 and 8 are special and cannot be used
316 	 * as inputs.
317 	 */
318 	if (zynq_gpio_is_zynq(gpio) && bank_num == 0 &&
319 	    (bank_pin_num == 7 || bank_pin_num == 8))
320 		return -EINVAL;
321 
322 	/* clear the bit in direction mode reg to set the pin as input */
323 	spin_lock_irqsave(&gpio->dirlock, flags);
324 	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
325 	reg &= ~BIT(bank_pin_num);
326 	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
327 	spin_unlock_irqrestore(&gpio->dirlock, flags);
328 
329 	return 0;
330 }
331 
332 /**
333  * zynq_gpio_dir_out - Set the direction of the specified GPIO pin as output
334  * @chip:	gpio_chip instance to be worked on
335  * @pin:	gpio pin number within the device
336  * @state:	value to be written to specified pin
337  *
338  * This function sets the direction of specified GPIO pin as output, configures
339  * the Output Enable register for the pin and uses zynq_gpio_set to set
340  * the state of the pin to the value specified.
341  *
342  * Return: 0 always
343  */
344 static int zynq_gpio_dir_out(struct gpio_chip *chip, unsigned int pin,
345 			     int state)
346 {
347 	u32 reg;
348 	unsigned int bank_num, bank_pin_num;
349 	unsigned long flags;
350 	struct zynq_gpio *gpio = gpiochip_get_data(chip);
351 
352 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);
353 
354 	/* set the GPIO pin as output */
355 	spin_lock_irqsave(&gpio->dirlock, flags);
356 	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
357 	reg |= BIT(bank_pin_num);
358 	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
359 
360 	/* configure the output enable reg for the pin */
361 	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num));
362 	reg |= BIT(bank_pin_num);
363 	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num));
364 	spin_unlock_irqrestore(&gpio->dirlock, flags);
365 
366 	/* set the state of the pin */
367 	zynq_gpio_set_value(chip, pin, state);
368 	return 0;
369 }
370 
371 /**
372  * zynq_gpio_get_direction - Read the direction of the specified GPIO pin
373  * @chip:	gpio_chip instance to be worked on
374  * @pin:	gpio pin number within the device
375  *
376  * This function returns the direction of the specified GPIO.
377  *
378  * Return: GPIO_LINE_DIRECTION_OUT or GPIO_LINE_DIRECTION_IN
379  */
380 static int zynq_gpio_get_direction(struct gpio_chip *chip, unsigned int pin)
381 {
382 	u32 reg;
383 	unsigned int bank_num, bank_pin_num;
384 	struct zynq_gpio *gpio = gpiochip_get_data(chip);
385 
386 	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);
387 
388 	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
389 
390 	if (reg & BIT(bank_pin_num))
391 		return GPIO_LINE_DIRECTION_OUT;
392 
393 	return GPIO_LINE_DIRECTION_IN;
394 }
395 
396 /**
397  * zynq_gpio_irq_mask - Disable the interrupts for a gpio pin
398  * @irq_data:	per irq and chip data passed down to chip functions
399  *
400  * This function calculates gpio pin number from irq number and sets the
401  * bit in the Interrupt Disable register of the corresponding bank to disable
402  * interrupts for that pin.
403  */
404 static void zynq_gpio_irq_mask(struct irq_data *irq_data)
405 {
406 	unsigned int device_pin_num, bank_num, bank_pin_num;
407 	struct zynq_gpio *gpio =
408 		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));
409 
410 	device_pin_num = irq_data->hwirq;
411 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
412 	writel_relaxed(BIT(bank_pin_num),
413 		       gpio->base_addr + ZYNQ_GPIO_INTDIS_OFFSET(bank_num));
414 }
415 
416 /**
417  * zynq_gpio_irq_unmask - Enable the interrupts for a gpio pin
418  * @irq_data:	irq data containing irq number of gpio pin for the interrupt
419  *		to enable
420  *
421  * This function calculates the gpio pin number from irq number and sets the
422  * bit in the Interrupt Enable register of the corresponding bank to enable
423  * interrupts for that pin.
424  */
425 static void zynq_gpio_irq_unmask(struct irq_data *irq_data)
426 {
427 	unsigned int device_pin_num, bank_num, bank_pin_num;
428 	struct zynq_gpio *gpio =
429 		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));
430 
431 	device_pin_num = irq_data->hwirq;
432 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
433 	writel_relaxed(BIT(bank_pin_num),
434 		       gpio->base_addr + ZYNQ_GPIO_INTEN_OFFSET(bank_num));
435 }
436 
437 /**
438  * zynq_gpio_irq_ack - Acknowledge the interrupt of a gpio pin
439  * @irq_data:	irq data containing irq number of gpio pin for the interrupt
440  *		to ack
441  *
442  * This function calculates gpio pin number from irq number and sets the bit
443  * in the Interrupt Status Register of the corresponding bank, to ACK the irq.
444  */
445 static void zynq_gpio_irq_ack(struct irq_data *irq_data)
446 {
447 	unsigned int device_pin_num, bank_num, bank_pin_num;
448 	struct zynq_gpio *gpio =
449 		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));
450 
451 	device_pin_num = irq_data->hwirq;
452 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
453 	writel_relaxed(BIT(bank_pin_num),
454 		       gpio->base_addr + ZYNQ_GPIO_INTSTS_OFFSET(bank_num));
455 }
456 
457 /**
458  * zynq_gpio_irq_enable - Enable the interrupts for a gpio pin
459  * @irq_data:	irq data containing irq number of gpio pin for the interrupt
460  *		to enable
461  *
462  * Clears the INTSTS bit and unmasks the given interrupt.
463  */
464 static void zynq_gpio_irq_enable(struct irq_data *irq_data)
465 {
466 	/*
467 	 * The Zynq GPIO controller does not disable interrupt detection when
468 	 * the interrupt is masked and only disables the propagation of the
469 	 * interrupt. This means when the controller detects an interrupt
470 	 * condition while the interrupt is logically disabled it will propagate
471 	 * that interrupt event once the interrupt is enabled. This will cause
472 	 * the interrupt consumer to see spurious interrupts to prevent this
473 	 * first make sure that the interrupt is not asserted and then enable
474 	 * it.
475 	 */
476 	zynq_gpio_irq_ack(irq_data);
477 	zynq_gpio_irq_unmask(irq_data);
478 }
479 
480 /**
481  * zynq_gpio_set_irq_type - Set the irq type for a gpio pin
482  * @irq_data:	irq data containing irq number of gpio pin
483  * @type:	interrupt type that is to be set for the gpio pin
484  *
485  * This function gets the gpio pin number and its bank from the gpio pin number
486  * and configures the INT_TYPE, INT_POLARITY and INT_ANY registers.
487  *
488  * Return: 0, negative error otherwise.
489  * TYPE-EDGE_RISING,  INT_TYPE - 1, INT_POLARITY - 1,  INT_ANY - 0;
490  * TYPE-EDGE_FALLING, INT_TYPE - 1, INT_POLARITY - 0,  INT_ANY - 0;
491  * TYPE-EDGE_BOTH,    INT_TYPE - 1, INT_POLARITY - NA, INT_ANY - 1;
492  * TYPE-LEVEL_HIGH,   INT_TYPE - 0, INT_POLARITY - 1,  INT_ANY - NA;
493  * TYPE-LEVEL_LOW,    INT_TYPE - 0, INT_POLARITY - 0,  INT_ANY - NA
494  */
495 static int zynq_gpio_set_irq_type(struct irq_data *irq_data, unsigned int type)
496 {
497 	u32 int_type, int_pol, int_any;
498 	unsigned int device_pin_num, bank_num, bank_pin_num;
499 	struct zynq_gpio *gpio =
500 		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));
501 
502 	device_pin_num = irq_data->hwirq;
503 	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
504 
505 	int_type = readl_relaxed(gpio->base_addr +
506 				 ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
507 	int_pol = readl_relaxed(gpio->base_addr +
508 				ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
509 	int_any = readl_relaxed(gpio->base_addr +
510 				ZYNQ_GPIO_INTANY_OFFSET(bank_num));
511 
512 	/*
513 	 * based on the type requested, configure the INT_TYPE, INT_POLARITY
514 	 * and INT_ANY registers
515 	 */
516 	switch (type) {
517 	case IRQ_TYPE_EDGE_RISING:
518 		int_type |= BIT(bank_pin_num);
519 		int_pol |= BIT(bank_pin_num);
520 		int_any &= ~BIT(bank_pin_num);
521 		break;
522 	case IRQ_TYPE_EDGE_FALLING:
523 		int_type |= BIT(bank_pin_num);
524 		int_pol &= ~BIT(bank_pin_num);
525 		int_any &= ~BIT(bank_pin_num);
526 		break;
527 	case IRQ_TYPE_EDGE_BOTH:
528 		int_type |= BIT(bank_pin_num);
529 		int_any |= BIT(bank_pin_num);
530 		break;
531 	case IRQ_TYPE_LEVEL_HIGH:
532 		int_type &= ~BIT(bank_pin_num);
533 		int_pol |= BIT(bank_pin_num);
534 		break;
535 	case IRQ_TYPE_LEVEL_LOW:
536 		int_type &= ~BIT(bank_pin_num);
537 		int_pol &= ~BIT(bank_pin_num);
538 		break;
539 	default:
540 		return -EINVAL;
541 	}
542 
543 	writel_relaxed(int_type,
544 		       gpio->base_addr + ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
545 	writel_relaxed(int_pol,
546 		       gpio->base_addr + ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
547 	writel_relaxed(int_any,
548 		       gpio->base_addr + ZYNQ_GPIO_INTANY_OFFSET(bank_num));
549 
550 	if (type & IRQ_TYPE_LEVEL_MASK)
551 		irq_set_chip_handler_name_locked(irq_data,
552 						 &zynq_gpio_level_irqchip,
553 						 handle_fasteoi_irq, NULL);
554 	else
555 		irq_set_chip_handler_name_locked(irq_data,
556 						 &zynq_gpio_edge_irqchip,
557 						 handle_level_irq, NULL);
558 
559 	return 0;
560 }
561 
562 static int zynq_gpio_set_wake(struct irq_data *data, unsigned int on)
563 {
564 	struct zynq_gpio *gpio =
565 		gpiochip_get_data(irq_data_get_irq_chip_data(data));
566 
567 	irq_set_irq_wake(gpio->irq, on);
568 
569 	return 0;
570 }
571 
572 static int zynq_gpio_irq_reqres(struct irq_data *d)
573 {
574 	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
575 	int ret;
576 
577 	ret = pm_runtime_resume_and_get(chip->parent);
578 	if (ret < 0)
579 		return ret;
580 
581 	return gpiochip_reqres_irq(chip, d->hwirq);
582 }
583 
584 static void zynq_gpio_irq_relres(struct irq_data *d)
585 {
586 	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
587 
588 	gpiochip_relres_irq(chip, d->hwirq);
589 	pm_runtime_put(chip->parent);
590 }
591 
592 /* irq chip descriptor */
593 static struct irq_chip zynq_gpio_level_irqchip = {
594 	.name		= DRIVER_NAME,
595 	.irq_enable	= zynq_gpio_irq_enable,
596 	.irq_eoi	= zynq_gpio_irq_ack,
597 	.irq_mask	= zynq_gpio_irq_mask,
598 	.irq_unmask	= zynq_gpio_irq_unmask,
599 	.irq_set_type	= zynq_gpio_set_irq_type,
600 	.irq_set_wake	= zynq_gpio_set_wake,
601 	.irq_request_resources = zynq_gpio_irq_reqres,
602 	.irq_release_resources = zynq_gpio_irq_relres,
603 	.flags		= IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED |
604 			  IRQCHIP_MASK_ON_SUSPEND,
605 };
606 
607 static struct irq_chip zynq_gpio_edge_irqchip = {
608 	.name		= DRIVER_NAME,
609 	.irq_enable	= zynq_gpio_irq_enable,
610 	.irq_ack	= zynq_gpio_irq_ack,
611 	.irq_mask	= zynq_gpio_irq_mask,
612 	.irq_unmask	= zynq_gpio_irq_unmask,
613 	.irq_set_type	= zynq_gpio_set_irq_type,
614 	.irq_set_wake	= zynq_gpio_set_wake,
615 	.irq_request_resources = zynq_gpio_irq_reqres,
616 	.irq_release_resources = zynq_gpio_irq_relres,
617 	.flags		= IRQCHIP_MASK_ON_SUSPEND,
618 };
619 
620 static void zynq_gpio_handle_bank_irq(struct zynq_gpio *gpio,
621 				      unsigned int bank_num,
622 				      unsigned long pending)
623 {
624 	unsigned int bank_offset = gpio->p_data->bank_min[bank_num];
625 	struct irq_domain *irqdomain = gpio->chip.irq.domain;
626 	int offset;
627 
628 	if (!pending)
629 		return;
630 
631 	for_each_set_bit(offset, &pending, 32) {
632 		unsigned int gpio_irq;
633 
634 		gpio_irq = irq_find_mapping(irqdomain, offset + bank_offset);
635 		generic_handle_irq(gpio_irq);
636 	}
637 }
638 
639 /**
640  * zynq_gpio_irqhandler - IRQ handler for the gpio banks of a gpio device
641  * @desc:	irq descriptor instance of the 'irq'
642  *
643  * This function reads the Interrupt Status Register of each bank to get the
644  * gpio pin number which has triggered an interrupt. It then acks the triggered
645  * interrupt and calls the pin specific handler set by the higher layer
646  * application for that pin.
647  * Note: A bug is reported if no handler is set for the gpio pin.
648  */
649 static void zynq_gpio_irqhandler(struct irq_desc *desc)
650 {
651 	u32 int_sts, int_enb;
652 	unsigned int bank_num;
653 	struct zynq_gpio *gpio =
654 		gpiochip_get_data(irq_desc_get_handler_data(desc));
655 	struct irq_chip *irqchip = irq_desc_get_chip(desc);
656 
657 	chained_irq_enter(irqchip, desc);
658 
659 	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
660 		int_sts = readl_relaxed(gpio->base_addr +
661 					ZYNQ_GPIO_INTSTS_OFFSET(bank_num));
662 		int_enb = readl_relaxed(gpio->base_addr +
663 					ZYNQ_GPIO_INTMASK_OFFSET(bank_num));
664 		zynq_gpio_handle_bank_irq(gpio, bank_num, int_sts & ~int_enb);
665 		if (gpio->p_data->quirks & GPIO_QUIRK_VERSAL)
666 			bank_num = bank_num + VERSAL_UNUSED_BANKS;
667 	}
668 
669 	chained_irq_exit(irqchip, desc);
670 }
671 
672 static void zynq_gpio_save_context(struct zynq_gpio *gpio)
673 {
674 	unsigned int bank_num;
675 
676 	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
677 		gpio->context.datalsw[bank_num] =
678 				readl_relaxed(gpio->base_addr +
679 				ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num));
680 		gpio->context.datamsw[bank_num] =
681 				readl_relaxed(gpio->base_addr +
682 				ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num));
683 		gpio->context.dirm[bank_num] = readl_relaxed(gpio->base_addr +
684 				ZYNQ_GPIO_DIRM_OFFSET(bank_num));
685 		gpio->context.int_en[bank_num] = readl_relaxed(gpio->base_addr +
686 				ZYNQ_GPIO_INTMASK_OFFSET(bank_num));
687 		gpio->context.int_type[bank_num] =
688 				readl_relaxed(gpio->base_addr +
689 				ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
690 		gpio->context.int_polarity[bank_num] =
691 				readl_relaxed(gpio->base_addr +
692 				ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
693 		gpio->context.int_any[bank_num] =
694 				readl_relaxed(gpio->base_addr +
695 				ZYNQ_GPIO_INTANY_OFFSET(bank_num));
696 		if (gpio->p_data->quirks & GPIO_QUIRK_VERSAL)
697 			bank_num = bank_num + VERSAL_UNUSED_BANKS;
698 	}
699 }
700 
701 static void zynq_gpio_restore_context(struct zynq_gpio *gpio)
702 {
703 	unsigned int bank_num;
704 
705 	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
706 		writel_relaxed(ZYNQ_GPIO_IXR_DISABLE_ALL, gpio->base_addr +
707 				ZYNQ_GPIO_INTDIS_OFFSET(bank_num));
708 		writel_relaxed(gpio->context.datalsw[bank_num],
709 			       gpio->base_addr +
710 			       ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num));
711 		writel_relaxed(gpio->context.datamsw[bank_num],
712 			       gpio->base_addr +
713 			       ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num));
714 		writel_relaxed(gpio->context.dirm[bank_num],
715 			       gpio->base_addr +
716 			       ZYNQ_GPIO_DIRM_OFFSET(bank_num));
717 		writel_relaxed(gpio->context.int_type[bank_num],
718 			       gpio->base_addr +
719 			       ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
720 		writel_relaxed(gpio->context.int_polarity[bank_num],
721 			       gpio->base_addr +
722 			       ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
723 		writel_relaxed(gpio->context.int_any[bank_num],
724 			       gpio->base_addr +
725 			       ZYNQ_GPIO_INTANY_OFFSET(bank_num));
726 		writel_relaxed(~(gpio->context.int_en[bank_num]),
727 			       gpio->base_addr +
728 			       ZYNQ_GPIO_INTEN_OFFSET(bank_num));
729 		if (gpio->p_data->quirks & GPIO_QUIRK_VERSAL)
730 			bank_num = bank_num + VERSAL_UNUSED_BANKS;
731 	}
732 }
733 
734 static int __maybe_unused zynq_gpio_suspend(struct device *dev)
735 {
736 	struct zynq_gpio *gpio = dev_get_drvdata(dev);
737 	struct irq_data *data = irq_get_irq_data(gpio->irq);
738 
739 	if (!device_may_wakeup(dev))
740 		disable_irq(gpio->irq);
741 
742 	if (!irqd_is_wakeup_set(data)) {
743 		zynq_gpio_save_context(gpio);
744 		return pm_runtime_force_suspend(dev);
745 	}
746 
747 	return 0;
748 }
749 
750 static int __maybe_unused zynq_gpio_resume(struct device *dev)
751 {
752 	struct zynq_gpio *gpio = dev_get_drvdata(dev);
753 	struct irq_data *data = irq_get_irq_data(gpio->irq);
754 	int ret;
755 
756 	if (!device_may_wakeup(dev))
757 		enable_irq(gpio->irq);
758 
759 	if (!irqd_is_wakeup_set(data)) {
760 		ret = pm_runtime_force_resume(dev);
761 		zynq_gpio_restore_context(gpio);
762 		return ret;
763 	}
764 
765 	return 0;
766 }
767 
768 static int __maybe_unused zynq_gpio_runtime_suspend(struct device *dev)
769 {
770 	struct zynq_gpio *gpio = dev_get_drvdata(dev);
771 
772 	clk_disable_unprepare(gpio->clk);
773 
774 	return 0;
775 }
776 
777 static int __maybe_unused zynq_gpio_runtime_resume(struct device *dev)
778 {
779 	struct zynq_gpio *gpio = dev_get_drvdata(dev);
780 
781 	return clk_prepare_enable(gpio->clk);
782 }
783 
784 static int zynq_gpio_request(struct gpio_chip *chip, unsigned int offset)
785 {
786 	int ret;
787 
788 	ret = pm_runtime_get_sync(chip->parent);
789 
790 	/*
791 	 * If the device is already active pm_runtime_get() will return 1 on
792 	 * success, but gpio_request still needs to return 0.
793 	 */
794 	return ret < 0 ? ret : 0;
795 }
796 
797 static void zynq_gpio_free(struct gpio_chip *chip, unsigned int offset)
798 {
799 	pm_runtime_put(chip->parent);
800 }
801 
802 static const struct dev_pm_ops zynq_gpio_dev_pm_ops = {
803 	SET_SYSTEM_SLEEP_PM_OPS(zynq_gpio_suspend, zynq_gpio_resume)
804 	SET_RUNTIME_PM_OPS(zynq_gpio_runtime_suspend,
805 			   zynq_gpio_runtime_resume, NULL)
806 };
807 
808 static const struct zynq_platform_data versal_gpio_def = {
809 	.label = "versal_gpio",
810 	.quirks = GPIO_QUIRK_VERSAL,
811 	.ngpio = 58,
812 	.max_bank = VERSAL_GPIO_MAX_BANK,
813 	.bank_min[0] = 0,
814 	.bank_max[0] = 25, /* 0 to 25 are connected to MIOs (26 pins) */
815 	.bank_min[3] = 26,
816 	.bank_max[3] = 57, /* Bank 3 is connected to FMIOs (32 pins) */
817 };
818 
819 static const struct zynq_platform_data pmc_gpio_def = {
820 	.label = "pmc_gpio",
821 	.ngpio = 116,
822 	.max_bank = PMC_GPIO_MAX_BANK,
823 	.bank_min[0] = 0,
824 	.bank_max[0] = 25, /* 0 to 25 are connected to MIOs (26 pins) */
825 	.bank_min[1] = 26,
826 	.bank_max[1] = 51, /* Bank 1 are connected to MIOs (26 pins) */
827 	.bank_min[3] = 52,
828 	.bank_max[3] = 83, /* Bank 3 is connected to EMIOs (32 pins) */
829 	.bank_min[4] = 84,
830 	.bank_max[4] = 115, /* Bank 4 is connected to EMIOs (32 pins) */
831 };
832 
833 static const struct zynq_platform_data zynqmp_gpio_def = {
834 	.label = "zynqmp_gpio",
835 	.quirks = GPIO_QUIRK_DATA_RO_BUG,
836 	.ngpio = ZYNQMP_GPIO_NR_GPIOS,
837 	.max_bank = ZYNQMP_GPIO_MAX_BANK,
838 	.bank_min[0] = ZYNQ_GPIO_BANK0_PIN_MIN(MP),
839 	.bank_max[0] = ZYNQ_GPIO_BANK0_PIN_MAX(MP),
840 	.bank_min[1] = ZYNQ_GPIO_BANK1_PIN_MIN(MP),
841 	.bank_max[1] = ZYNQ_GPIO_BANK1_PIN_MAX(MP),
842 	.bank_min[2] = ZYNQ_GPIO_BANK2_PIN_MIN(MP),
843 	.bank_max[2] = ZYNQ_GPIO_BANK2_PIN_MAX(MP),
844 	.bank_min[3] = ZYNQ_GPIO_BANK3_PIN_MIN(MP),
845 	.bank_max[3] = ZYNQ_GPIO_BANK3_PIN_MAX(MP),
846 	.bank_min[4] = ZYNQ_GPIO_BANK4_PIN_MIN(MP),
847 	.bank_max[4] = ZYNQ_GPIO_BANK4_PIN_MAX(MP),
848 	.bank_min[5] = ZYNQ_GPIO_BANK5_PIN_MIN(MP),
849 	.bank_max[5] = ZYNQ_GPIO_BANK5_PIN_MAX(MP),
850 };
851 
852 static const struct zynq_platform_data zynq_gpio_def = {
853 	.label = "zynq_gpio",
854 	.quirks = ZYNQ_GPIO_QUIRK_IS_ZYNQ | GPIO_QUIRK_DATA_RO_BUG,
855 	.ngpio = ZYNQ_GPIO_NR_GPIOS,
856 	.max_bank = ZYNQ_GPIO_MAX_BANK,
857 	.bank_min[0] = ZYNQ_GPIO_BANK0_PIN_MIN(),
858 	.bank_max[0] = ZYNQ_GPIO_BANK0_PIN_MAX(),
859 	.bank_min[1] = ZYNQ_GPIO_BANK1_PIN_MIN(),
860 	.bank_max[1] = ZYNQ_GPIO_BANK1_PIN_MAX(),
861 	.bank_min[2] = ZYNQ_GPIO_BANK2_PIN_MIN(),
862 	.bank_max[2] = ZYNQ_GPIO_BANK2_PIN_MAX(),
863 	.bank_min[3] = ZYNQ_GPIO_BANK3_PIN_MIN(),
864 	.bank_max[3] = ZYNQ_GPIO_BANK3_PIN_MAX(),
865 };
866 
867 static const struct of_device_id zynq_gpio_of_match[] = {
868 	{ .compatible = "xlnx,zynq-gpio-1.0", .data = &zynq_gpio_def },
869 	{ .compatible = "xlnx,zynqmp-gpio-1.0", .data = &zynqmp_gpio_def },
870 	{ .compatible = "xlnx,versal-gpio-1.0", .data = &versal_gpio_def },
871 	{ .compatible = "xlnx,pmc-gpio-1.0", .data = &pmc_gpio_def },
872 	{ /* end of table */ }
873 };
874 MODULE_DEVICE_TABLE(of, zynq_gpio_of_match);
875 
876 /**
877  * zynq_gpio_probe - Initialization method for a zynq_gpio device
878  * @pdev:	platform device instance
879  *
880  * This function allocates memory resources for the gpio device and registers
881  * all the banks of the device. It will also set up interrupts for the gpio
882  * pins.
883  * Note: Interrupts are disabled for all the banks during initialization.
884  *
885  * Return: 0 on success, negative error otherwise.
886  */
887 static int zynq_gpio_probe(struct platform_device *pdev)
888 {
889 	int ret, bank_num;
890 	struct zynq_gpio *gpio;
891 	struct gpio_chip *chip;
892 	struct gpio_irq_chip *girq;
893 	const struct of_device_id *match;
894 
895 	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
896 	if (!gpio)
897 		return -ENOMEM;
898 
899 	match = of_match_node(zynq_gpio_of_match, pdev->dev.of_node);
900 	if (!match) {
901 		dev_err(&pdev->dev, "of_match_node() failed\n");
902 		return -EINVAL;
903 	}
904 	gpio->p_data = match->data;
905 	platform_set_drvdata(pdev, gpio);
906 
907 	gpio->base_addr = devm_platform_ioremap_resource(pdev, 0);
908 	if (IS_ERR(gpio->base_addr))
909 		return PTR_ERR(gpio->base_addr);
910 
911 	gpio->irq = platform_get_irq(pdev, 0);
912 	if (gpio->irq < 0)
913 		return gpio->irq;
914 
915 	/* configure the gpio chip */
916 	chip = &gpio->chip;
917 	chip->label = gpio->p_data->label;
918 	chip->owner = THIS_MODULE;
919 	chip->parent = &pdev->dev;
920 	chip->get = zynq_gpio_get_value;
921 	chip->set = zynq_gpio_set_value;
922 	chip->request = zynq_gpio_request;
923 	chip->free = zynq_gpio_free;
924 	chip->direction_input = zynq_gpio_dir_in;
925 	chip->direction_output = zynq_gpio_dir_out;
926 	chip->get_direction = zynq_gpio_get_direction;
927 	chip->base = of_alias_get_id(pdev->dev.of_node, "gpio");
928 	chip->ngpio = gpio->p_data->ngpio;
929 
930 	/* Retrieve GPIO clock */
931 	gpio->clk = devm_clk_get(&pdev->dev, NULL);
932 	if (IS_ERR(gpio->clk))
933 		return dev_err_probe(&pdev->dev, PTR_ERR(gpio->clk), "input clock not found.\n");
934 
935 	ret = clk_prepare_enable(gpio->clk);
936 	if (ret) {
937 		dev_err(&pdev->dev, "Unable to enable clock.\n");
938 		return ret;
939 	}
940 
941 	spin_lock_init(&gpio->dirlock);
942 
943 	pm_runtime_set_active(&pdev->dev);
944 	pm_runtime_enable(&pdev->dev);
945 	ret = pm_runtime_resume_and_get(&pdev->dev);
946 	if (ret < 0)
947 		goto err_pm_dis;
948 
949 	/* disable interrupts for all banks */
950 	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
951 		writel_relaxed(ZYNQ_GPIO_IXR_DISABLE_ALL, gpio->base_addr +
952 			       ZYNQ_GPIO_INTDIS_OFFSET(bank_num));
953 		if (gpio->p_data->quirks & GPIO_QUIRK_VERSAL)
954 			bank_num = bank_num + VERSAL_UNUSED_BANKS;
955 	}
956 
957 	/* Set up the GPIO irqchip */
958 	girq = &chip->irq;
959 	girq->chip = &zynq_gpio_edge_irqchip;
960 	girq->parent_handler = zynq_gpio_irqhandler;
961 	girq->num_parents = 1;
962 	girq->parents = devm_kcalloc(&pdev->dev, 1,
963 				     sizeof(*girq->parents),
964 				     GFP_KERNEL);
965 	if (!girq->parents) {
966 		ret = -ENOMEM;
967 		goto err_pm_put;
968 	}
969 	girq->parents[0] = gpio->irq;
970 	girq->default_type = IRQ_TYPE_NONE;
971 	girq->handler = handle_level_irq;
972 
973 	/* report a bug if gpio chip registration fails */
974 	ret = gpiochip_add_data(chip, gpio);
975 	if (ret) {
976 		dev_err(&pdev->dev, "Failed to add gpio chip\n");
977 		goto err_pm_put;
978 	}
979 
980 	irq_set_status_flags(gpio->irq, IRQ_DISABLE_UNLAZY);
981 	device_init_wakeup(&pdev->dev, 1);
982 	pm_runtime_put(&pdev->dev);
983 
984 	return 0;
985 
986 err_pm_put:
987 	pm_runtime_put(&pdev->dev);
988 err_pm_dis:
989 	pm_runtime_disable(&pdev->dev);
990 	clk_disable_unprepare(gpio->clk);
991 
992 	return ret;
993 }
994 
995 /**
996  * zynq_gpio_remove - Driver removal function
997  * @pdev:	platform device instance
998  *
999  * Return: 0 always
1000  */
1001 static int zynq_gpio_remove(struct platform_device *pdev)
1002 {
1003 	struct zynq_gpio *gpio = platform_get_drvdata(pdev);
1004 
1005 	pm_runtime_get_sync(&pdev->dev);
1006 	gpiochip_remove(&gpio->chip);
1007 	clk_disable_unprepare(gpio->clk);
1008 	device_set_wakeup_capable(&pdev->dev, 0);
1009 	pm_runtime_disable(&pdev->dev);
1010 	return 0;
1011 }
1012 
1013 static struct platform_driver zynq_gpio_driver = {
1014 	.driver	= {
1015 		.name = DRIVER_NAME,
1016 		.pm = &zynq_gpio_dev_pm_ops,
1017 		.of_match_table = zynq_gpio_of_match,
1018 	},
1019 	.probe = zynq_gpio_probe,
1020 	.remove = zynq_gpio_remove,
1021 };
1022 
1023 /**
1024  * zynq_gpio_init - Initial driver registration call
1025  *
1026  * Return: value from platform_driver_register
1027  */
1028 static int __init zynq_gpio_init(void)
1029 {
1030 	return platform_driver_register(&zynq_gpio_driver);
1031 }
1032 postcore_initcall(zynq_gpio_init);
1033 
1034 static void __exit zynq_gpio_exit(void)
1035 {
1036 	platform_driver_unregister(&zynq_gpio_driver);
1037 }
1038 module_exit(zynq_gpio_exit);
1039 
1040 MODULE_AUTHOR("Xilinx Inc.");
1041 MODULE_DESCRIPTION("Zynq GPIO driver");
1042 MODULE_LICENSE("GPL");
1043