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-rw-r--r--arch/mips/jz4740/gpio.c604
1 files changed, 604 insertions, 0 deletions
diff --git a/arch/mips/jz4740/gpio.c b/arch/mips/jz4740/gpio.c
new file mode 100644
index 000000000000..38f60f35156c
--- /dev/null
+++ b/arch/mips/jz4740/gpio.c
@@ -0,0 +1,604 @@
1/*
2 * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
3 * JZ4740 platform GPIO support
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * You should have received a copy of the GNU General Public License along
11 * with this program; if not, write to the Free Software Foundation, Inc.,
12 * 675 Mass Ave, Cambridge, MA 02139, USA.
13 *
14 */
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/init.h>
19
20#include <linux/spinlock.h>
21#include <linux/sysdev.h>
22#include <linux/io.h>
23#include <linux/gpio.h>
24#include <linux/delay.h>
25#include <linux/interrupt.h>
26#include <linux/bitops.h>
27
28#include <linux/debugfs.h>
29#include <linux/seq_file.h>
30
31#include <asm/mach-jz4740/base.h>
32
33#define JZ4740_GPIO_BASE_A (32*0)
34#define JZ4740_GPIO_BASE_B (32*1)
35#define JZ4740_GPIO_BASE_C (32*2)
36#define JZ4740_GPIO_BASE_D (32*3)
37
38#define JZ4740_GPIO_NUM_A 32
39#define JZ4740_GPIO_NUM_B 32
40#define JZ4740_GPIO_NUM_C 31
41#define JZ4740_GPIO_NUM_D 32
42
43#define JZ4740_IRQ_GPIO_BASE_A (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_A)
44#define JZ4740_IRQ_GPIO_BASE_B (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_B)
45#define JZ4740_IRQ_GPIO_BASE_C (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_C)
46#define JZ4740_IRQ_GPIO_BASE_D (JZ4740_IRQ_GPIO(0) + JZ4740_GPIO_BASE_D)
47
48#define JZ_REG_GPIO_PIN 0x00
49#define JZ_REG_GPIO_DATA 0x10
50#define JZ_REG_GPIO_DATA_SET 0x14
51#define JZ_REG_GPIO_DATA_CLEAR 0x18
52#define JZ_REG_GPIO_MASK 0x20
53#define JZ_REG_GPIO_MASK_SET 0x24
54#define JZ_REG_GPIO_MASK_CLEAR 0x28
55#define JZ_REG_GPIO_PULL 0x30
56#define JZ_REG_GPIO_PULL_SET 0x34
57#define JZ_REG_GPIO_PULL_CLEAR 0x38
58#define JZ_REG_GPIO_FUNC 0x40
59#define JZ_REG_GPIO_FUNC_SET 0x44
60#define JZ_REG_GPIO_FUNC_CLEAR 0x48
61#define JZ_REG_GPIO_SELECT 0x50
62#define JZ_REG_GPIO_SELECT_SET 0x54
63#define JZ_REG_GPIO_SELECT_CLEAR 0x58
64#define JZ_REG_GPIO_DIRECTION 0x60
65#define JZ_REG_GPIO_DIRECTION_SET 0x64
66#define JZ_REG_GPIO_DIRECTION_CLEAR 0x68
67#define JZ_REG_GPIO_TRIGGER 0x70
68#define JZ_REG_GPIO_TRIGGER_SET 0x74
69#define JZ_REG_GPIO_TRIGGER_CLEAR 0x78
70#define JZ_REG_GPIO_FLAG 0x80
71#define JZ_REG_GPIO_FLAG_CLEAR 0x14
72
73#define GPIO_TO_BIT(gpio) BIT(gpio & 0x1f)
74#define GPIO_TO_REG(gpio, reg) (gpio_to_jz_gpio_chip(gpio)->base + (reg))
75#define CHIP_TO_REG(chip, reg) (gpio_chip_to_jz_gpio_chip(chip)->base + (reg))
76
77struct jz_gpio_chip {
78 unsigned int irq;
79 unsigned int irq_base;
80 uint32_t wakeup;
81 uint32_t suspend_mask;
82 uint32_t edge_trigger_both;
83
84 void __iomem *base;
85
86 spinlock_t lock;
87
88 struct gpio_chip gpio_chip;
89 struct irq_chip irq_chip;
90 struct sys_device sysdev;
91};
92
93static struct jz_gpio_chip jz4740_gpio_chips[];
94
95static inline struct jz_gpio_chip *gpio_to_jz_gpio_chip(unsigned int gpio)
96{
97 return &jz4740_gpio_chips[gpio >> 5];
98}
99
100static inline struct jz_gpio_chip *gpio_chip_to_jz_gpio_chip(struct gpio_chip *gpio_chip)
101{
102 return container_of(gpio_chip, struct jz_gpio_chip, gpio_chip);
103}
104
105static inline struct jz_gpio_chip *irq_to_jz_gpio_chip(unsigned int irq)
106{
107 return get_irq_chip_data(irq);
108}
109
110static inline void jz_gpio_write_bit(unsigned int gpio, unsigned int reg)
111{
112 writel(GPIO_TO_BIT(gpio), GPIO_TO_REG(gpio, reg));
113}
114
115int jz_gpio_set_function(int gpio, enum jz_gpio_function function)
116{
117 if (function == JZ_GPIO_FUNC_NONE) {
118 jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_CLEAR);
119 jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
120 jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
121 } else {
122 jz_gpio_write_bit(gpio, JZ_REG_GPIO_FUNC_SET);
123 jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_CLEAR);
124 switch (function) {
125 case JZ_GPIO_FUNC1:
126 jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_CLEAR);
127 break;
128 case JZ_GPIO_FUNC3:
129 jz_gpio_write_bit(gpio, JZ_REG_GPIO_TRIGGER_SET);
130 case JZ_GPIO_FUNC2: /* Falltrough */
131 jz_gpio_write_bit(gpio, JZ_REG_GPIO_SELECT_SET);
132 break;
133 default:
134 BUG();
135 break;
136 }
137 }
138
139 return 0;
140}
141EXPORT_SYMBOL_GPL(jz_gpio_set_function);
142
143int jz_gpio_bulk_request(const struct jz_gpio_bulk_request *request, size_t num)
144{
145 size_t i;
146 int ret;
147
148 for (i = 0; i < num; ++i, ++request) {
149 ret = gpio_request(request->gpio, request->name);
150 if (ret)
151 goto err;
152 jz_gpio_set_function(request->gpio, request->function);
153 }
154
155 return 0;
156
157err:
158 for (--request; i > 0; --i, --request) {
159 gpio_free(request->gpio);
160 jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
161 }
162
163 return ret;
164}
165EXPORT_SYMBOL_GPL(jz_gpio_bulk_request);
166
167void jz_gpio_bulk_free(const struct jz_gpio_bulk_request *request, size_t num)
168{
169 size_t i;
170
171 for (i = 0; i < num; ++i, ++request) {
172 gpio_free(request->gpio);
173 jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
174 }
175
176}
177EXPORT_SYMBOL_GPL(jz_gpio_bulk_free);
178
179void jz_gpio_bulk_suspend(const struct jz_gpio_bulk_request *request, size_t num)
180{
181 size_t i;
182
183 for (i = 0; i < num; ++i, ++request) {
184 jz_gpio_set_function(request->gpio, JZ_GPIO_FUNC_NONE);
185 jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_DIRECTION_CLEAR);
186 jz_gpio_write_bit(request->gpio, JZ_REG_GPIO_PULL_SET);
187 }
188}
189EXPORT_SYMBOL_GPL(jz_gpio_bulk_suspend);
190
191void jz_gpio_bulk_resume(const struct jz_gpio_bulk_request *request, size_t num)
192{
193 size_t i;
194
195 for (i = 0; i < num; ++i, ++request)
196 jz_gpio_set_function(request->gpio, request->function);
197}
198EXPORT_SYMBOL_GPL(jz_gpio_bulk_resume);
199
200void jz_gpio_enable_pullup(unsigned gpio)
201{
202 jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_CLEAR);
203}
204EXPORT_SYMBOL_GPL(jz_gpio_enable_pullup);
205
206void jz_gpio_disable_pullup(unsigned gpio)
207{
208 jz_gpio_write_bit(gpio, JZ_REG_GPIO_PULL_SET);
209}
210EXPORT_SYMBOL_GPL(jz_gpio_disable_pullup);
211
212static int jz_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
213{
214 return !!(readl(CHIP_TO_REG(chip, JZ_REG_GPIO_PIN)) & BIT(gpio));
215}
216
217static void jz_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
218{
219 uint32_t __iomem *reg = CHIP_TO_REG(chip, JZ_REG_GPIO_DATA_SET);
220 reg += !value;
221 writel(BIT(gpio), reg);
222}
223
224static int jz_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
225 int value)
226{
227 writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_SET));
228 jz_gpio_set_value(chip, gpio, value);
229
230 return 0;
231}
232
233static int jz_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
234{
235 writel(BIT(gpio), CHIP_TO_REG(chip, JZ_REG_GPIO_DIRECTION_CLEAR));
236
237 return 0;
238}
239
240int jz_gpio_port_direction_input(int port, uint32_t mask)
241{
242 writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_CLEAR));
243
244 return 0;
245}
246EXPORT_SYMBOL(jz_gpio_port_direction_input);
247
248int jz_gpio_port_direction_output(int port, uint32_t mask)
249{
250 writel(mask, GPIO_TO_REG(port, JZ_REG_GPIO_DIRECTION_SET));
251
252 return 0;
253}
254EXPORT_SYMBOL(jz_gpio_port_direction_output);
255
256void jz_gpio_port_set_value(int port, uint32_t value, uint32_t mask)
257{
258 writel(~value & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_CLEAR));
259 writel(value & mask, GPIO_TO_REG(port, JZ_REG_GPIO_DATA_SET));
260}
261EXPORT_SYMBOL(jz_gpio_port_set_value);
262
263uint32_t jz_gpio_port_get_value(int port, uint32_t mask)
264{
265 uint32_t value = readl(GPIO_TO_REG(port, JZ_REG_GPIO_PIN));
266
267 return value & mask;
268}
269EXPORT_SYMBOL(jz_gpio_port_get_value);
270
271int gpio_to_irq(unsigned gpio)
272{
273 return JZ4740_IRQ_GPIO(0) + gpio;
274}
275EXPORT_SYMBOL_GPL(gpio_to_irq);
276
277int irq_to_gpio(unsigned irq)
278{
279 return irq - JZ4740_IRQ_GPIO(0);
280}
281EXPORT_SYMBOL_GPL(irq_to_gpio);
282
283#define IRQ_TO_BIT(irq) BIT(irq_to_gpio(irq) & 0x1f)
284
285static void jz_gpio_check_trigger_both(struct jz_gpio_chip *chip, unsigned int irq)
286{
287 uint32_t value;
288 void __iomem *reg;
289 uint32_t mask = IRQ_TO_BIT(irq);
290
291 if (!(chip->edge_trigger_both & mask))
292 return;
293
294 reg = chip->base;
295
296 value = readl(chip->base + JZ_REG_GPIO_PIN);
297 if (value & mask)
298 reg += JZ_REG_GPIO_DIRECTION_CLEAR;
299 else
300 reg += JZ_REG_GPIO_DIRECTION_SET;
301
302 writel(mask, reg);
303}
304
305static void jz_gpio_irq_demux_handler(unsigned int irq, struct irq_desc *desc)
306{
307 uint32_t flag;
308 unsigned int gpio_irq;
309 unsigned int gpio_bank;
310 struct jz_gpio_chip *chip = get_irq_desc_data(desc);
311
312 gpio_bank = JZ4740_IRQ_GPIO0 - irq;
313
314 flag = readl(chip->base + JZ_REG_GPIO_FLAG);
315
316 if (!flag)
317 return;
318
319 gpio_irq = __fls(flag);
320
321 jz_gpio_check_trigger_both(chip, irq);
322
323 gpio_irq += (gpio_bank << 5) + JZ4740_IRQ_GPIO(0);
324
325 generic_handle_irq(gpio_irq);
326};
327
328static inline void jz_gpio_set_irq_bit(unsigned int irq, unsigned int reg)
329{
330 struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
331 writel(IRQ_TO_BIT(irq), chip->base + reg);
332}
333
334static void jz_gpio_irq_mask(unsigned int irq)
335{
336 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_MASK_SET);
337};
338
339static void jz_gpio_irq_unmask(unsigned int irq)
340{
341 struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
342
343 jz_gpio_check_trigger_both(chip, irq);
344
345 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_MASK_CLEAR);
346};
347
348/* TODO: Check if function is gpio */
349static unsigned int jz_gpio_irq_startup(unsigned int irq)
350{
351 struct irq_desc *desc = irq_to_desc(irq);
352
353 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_SELECT_SET);
354
355 desc->status &= ~IRQ_MASKED;
356 jz_gpio_irq_unmask(irq);
357
358 return 0;
359}
360
361static void jz_gpio_irq_shutdown(unsigned int irq)
362{
363 struct irq_desc *desc = irq_to_desc(irq);
364
365 jz_gpio_irq_mask(irq);
366 desc->status |= IRQ_MASKED;
367
368 /* Set direction to input */
369 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
370 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_SELECT_CLEAR);
371}
372
373static void jz_gpio_irq_ack(unsigned int irq)
374{
375 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_FLAG_CLEAR);
376};
377
378static int jz_gpio_irq_set_type(unsigned int irq, unsigned int flow_type)
379{
380 struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
381 struct irq_desc *desc = irq_to_desc(irq);
382
383 jz_gpio_irq_mask(irq);
384
385 if (flow_type == IRQ_TYPE_EDGE_BOTH) {
386 uint32_t value = readl(chip->base + JZ_REG_GPIO_PIN);
387 if (value & IRQ_TO_BIT(irq))
388 flow_type = IRQ_TYPE_EDGE_FALLING;
389 else
390 flow_type = IRQ_TYPE_EDGE_RISING;
391 chip->edge_trigger_both |= IRQ_TO_BIT(irq);
392 } else {
393 chip->edge_trigger_both &= ~IRQ_TO_BIT(irq);
394 }
395
396 switch (flow_type) {
397 case IRQ_TYPE_EDGE_RISING:
398 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_SET);
399 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_SET);
400 break;
401 case IRQ_TYPE_EDGE_FALLING:
402 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
403 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_SET);
404 break;
405 case IRQ_TYPE_LEVEL_HIGH:
406 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_SET);
407 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_CLEAR);
408 break;
409 case IRQ_TYPE_LEVEL_LOW:
410 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_DIRECTION_CLEAR);
411 jz_gpio_set_irq_bit(irq, JZ_REG_GPIO_TRIGGER_CLEAR);
412 break;
413 default:
414 return -EINVAL;
415 }
416
417 if (!(desc->status & IRQ_MASKED))
418 jz_gpio_irq_unmask(irq);
419
420 return 0;
421}
422
423static int jz_gpio_irq_set_wake(unsigned int irq, unsigned int on)
424{
425 struct jz_gpio_chip *chip = irq_to_jz_gpio_chip(irq);
426 spin_lock(&chip->lock);
427 if (on)
428 chip->wakeup |= IRQ_TO_BIT(irq);
429 else
430 chip->wakeup &= ~IRQ_TO_BIT(irq);
431 spin_unlock(&chip->lock);
432
433 set_irq_wake(chip->irq, on);
434 return 0;
435}
436
437/*
438 * This lock class tells lockdep that GPIO irqs are in a different
439 * category than their parents, so it won't report false recursion.
440 */
441static struct lock_class_key gpio_lock_class;
442
443#define JZ4740_GPIO_CHIP(_bank) { \
444 .irq_base = JZ4740_IRQ_GPIO_BASE_ ## _bank, \
445 .gpio_chip = { \
446 .label = "Bank " # _bank, \
447 .owner = THIS_MODULE, \
448 .set = jz_gpio_set_value, \
449 .get = jz_gpio_get_value, \
450 .direction_output = jz_gpio_direction_output, \
451 .direction_input = jz_gpio_direction_input, \
452 .base = JZ4740_GPIO_BASE_ ## _bank, \
453 .ngpio = JZ4740_GPIO_NUM_ ## _bank, \
454 }, \
455 .irq_chip = { \
456 .name = "GPIO Bank " # _bank, \
457 .mask = jz_gpio_irq_mask, \
458 .unmask = jz_gpio_irq_unmask, \
459 .ack = jz_gpio_irq_ack, \
460 .startup = jz_gpio_irq_startup, \
461 .shutdown = jz_gpio_irq_shutdown, \
462 .set_type = jz_gpio_irq_set_type, \
463 .set_wake = jz_gpio_irq_set_wake, \
464 }, \
465}
466
467static struct jz_gpio_chip jz4740_gpio_chips[] = {
468 JZ4740_GPIO_CHIP(A),
469 JZ4740_GPIO_CHIP(B),
470 JZ4740_GPIO_CHIP(C),
471 JZ4740_GPIO_CHIP(D),
472};
473
474static inline struct jz_gpio_chip *sysdev_to_chip(struct sys_device *dev)
475{
476 return container_of(dev, struct jz_gpio_chip, sysdev);
477}
478
479static int jz4740_gpio_suspend(struct sys_device *dev, pm_message_t state)
480{
481 struct jz_gpio_chip *chip = sysdev_to_chip(dev);
482
483 chip->suspend_mask = readl(chip->base + JZ_REG_GPIO_MASK);
484 writel(~(chip->wakeup), chip->base + JZ_REG_GPIO_MASK_SET);
485 writel(chip->wakeup, chip->base + JZ_REG_GPIO_MASK_CLEAR);
486
487 return 0;
488}
489
490static int jz4740_gpio_resume(struct sys_device *dev)
491{
492 struct jz_gpio_chip *chip = sysdev_to_chip(dev);
493 uint32_t mask = chip->suspend_mask;
494
495 writel(~mask, chip->base + JZ_REG_GPIO_MASK_CLEAR);
496 writel(mask, chip->base + JZ_REG_GPIO_MASK_SET);
497
498 return 0;
499}
500
501static struct sysdev_class jz4740_gpio_sysdev_class = {
502 .name = "gpio",
503 .suspend = jz4740_gpio_suspend,
504 .resume = jz4740_gpio_resume,
505};
506
507static int jz4740_gpio_chip_init(struct jz_gpio_chip *chip, unsigned int id)
508{
509 int ret, irq;
510
511 chip->sysdev.id = id;
512 chip->sysdev.cls = &jz4740_gpio_sysdev_class;
513 ret = sysdev_register(&chip->sysdev);
514
515 if (ret)
516 return ret;
517
518 spin_lock_init(&chip->lock);
519
520 chip->base = ioremap(JZ4740_GPIO_BASE_ADDR + (id * 0x100), 0x100);
521
522 gpiochip_add(&chip->gpio_chip);
523
524 chip->irq = JZ4740_IRQ_INTC_GPIO(id);
525 set_irq_data(chip->irq, chip);
526 set_irq_chained_handler(chip->irq, jz_gpio_irq_demux_handler);
527
528 for (irq = chip->irq_base; irq < chip->irq_base + chip->gpio_chip.ngpio; ++irq) {
529 lockdep_set_class(&irq_desc[irq].lock, &gpio_lock_class);
530 set_irq_chip_data(irq, chip);
531 set_irq_chip_and_handler(irq, &chip->irq_chip, handle_level_irq);
532 }
533
534 return 0;
535}
536
537static int __init jz4740_gpio_init(void)
538{
539 unsigned int i;
540 int ret;
541
542 ret = sysdev_class_register(&jz4740_gpio_sysdev_class);
543 if (ret)
544 return ret;
545
546 for (i = 0; i < ARRAY_SIZE(jz4740_gpio_chips); ++i)
547 jz4740_gpio_chip_init(&jz4740_gpio_chips[i], i);
548
549 printk(KERN_INFO "JZ4740 GPIO initalized\n");
550
551 return 0;
552}
553arch_initcall(jz4740_gpio_init);
554
555#ifdef CONFIG_DEBUG_FS
556
557static inline void gpio_seq_reg(struct seq_file *s, struct jz_gpio_chip *chip,
558 const char *name, unsigned int reg)
559{
560 seq_printf(s, "\t%s: %08x\n", name, readl(chip->base + reg));
561}
562
563static int gpio_regs_show(struct seq_file *s, void *unused)
564{
565 struct jz_gpio_chip *chip = jz4740_gpio_chips;
566 int i;
567
568 for (i = 0; i < ARRAY_SIZE(jz4740_gpio_chips); ++i, ++chip) {
569 seq_printf(s, "==GPIO %d==\n", i);
570 gpio_seq_reg(s, chip, "Pin", JZ_REG_GPIO_PIN);
571 gpio_seq_reg(s, chip, "Data", JZ_REG_GPIO_DATA);
572 gpio_seq_reg(s, chip, "Mask", JZ_REG_GPIO_MASK);
573 gpio_seq_reg(s, chip, "Pull", JZ_REG_GPIO_PULL);
574 gpio_seq_reg(s, chip, "Func", JZ_REG_GPIO_FUNC);
575 gpio_seq_reg(s, chip, "Select", JZ_REG_GPIO_SELECT);
576 gpio_seq_reg(s, chip, "Direction", JZ_REG_GPIO_DIRECTION);
577 gpio_seq_reg(s, chip, "Trigger", JZ_REG_GPIO_TRIGGER);
578 gpio_seq_reg(s, chip, "Flag", JZ_REG_GPIO_FLAG);
579 }
580
581 return 0;
582}
583
584static int gpio_regs_open(struct inode *inode, struct file *file)
585{
586 return single_open(file, gpio_regs_show, NULL);
587}
588
589static const struct file_operations gpio_regs_operations = {
590 .open = gpio_regs_open,
591 .read = seq_read,
592 .llseek = seq_lseek,
593 .release = single_release,
594};
595
596static int __init gpio_debugfs_init(void)
597{
598 (void) debugfs_create_file("jz_regs_gpio", S_IFREG | S_IRUGO,
599 NULL, NULL, &gpio_regs_operations);
600 return 0;
601}
602subsys_initcall(gpio_debugfs_init);
603
604#endif