ARM: tegra: moving the CPU power timer function to PMC driver
[linux-2.6-block.git] / drivers / gpio / gpio-tegra.c
CommitLineData
3c92db9a
EG
1/*
2 * arch/arm/mach-tegra/gpio.c
3 *
4 * Copyright (c) 2010 Google, Inc
5 *
6 * Author:
7 * Erik Gilling <konkers@google.com>
8 *
9 * This software is licensed under the terms of the GNU General Public
10 * License version 2, as published by the Free Software Foundation, and
11 * may be copied, distributed, and modified under those terms.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 */
19
641d0342 20#include <linux/err.h>
3c92db9a
EG
21#include <linux/init.h>
22#include <linux/irq.h>
2e47b8b3 23#include <linux/interrupt.h>
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EG
24#include <linux/io.h>
25#include <linux/gpio.h>
5c1e2c9d 26#include <linux/of_device.h>
88d8951e
SW
27#include <linux/platform_device.h>
28#include <linux/module.h>
6f74dc9b 29#include <linux/irqdomain.h>
3e215d0a 30#include <linux/pinctrl/consumer.h>
8939ddc7 31#include <linux/pm.h>
3c92db9a 32
98022940
WD
33#include <asm/mach/irq.h>
34
3c92db9a
EG
35#define GPIO_BANK(x) ((x) >> 5)
36#define GPIO_PORT(x) (((x) >> 3) & 0x3)
37#define GPIO_BIT(x) ((x) & 0x7)
38
5c1e2c9d
SW
39#define GPIO_REG(x) (GPIO_BANK(x) * tegra_gpio_bank_stride + \
40 GPIO_PORT(x) * 4)
3c92db9a
EG
41
42#define GPIO_CNF(x) (GPIO_REG(x) + 0x00)
43#define GPIO_OE(x) (GPIO_REG(x) + 0x10)
44#define GPIO_OUT(x) (GPIO_REG(x) + 0X20)
45#define GPIO_IN(x) (GPIO_REG(x) + 0x30)
46#define GPIO_INT_STA(x) (GPIO_REG(x) + 0x40)
47#define GPIO_INT_ENB(x) (GPIO_REG(x) + 0x50)
48#define GPIO_INT_LVL(x) (GPIO_REG(x) + 0x60)
49#define GPIO_INT_CLR(x) (GPIO_REG(x) + 0x70)
50
5c1e2c9d
SW
51#define GPIO_MSK_CNF(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x00)
52#define GPIO_MSK_OE(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x10)
53#define GPIO_MSK_OUT(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0X20)
54#define GPIO_MSK_INT_STA(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x40)
55#define GPIO_MSK_INT_ENB(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x50)
56#define GPIO_MSK_INT_LVL(x) (GPIO_REG(x) + tegra_gpio_upper_offset + 0x60)
3c92db9a
EG
57
58#define GPIO_INT_LVL_MASK 0x010101
59#define GPIO_INT_LVL_EDGE_RISING 0x000101
60#define GPIO_INT_LVL_EDGE_FALLING 0x000100
61#define GPIO_INT_LVL_EDGE_BOTH 0x010100
62#define GPIO_INT_LVL_LEVEL_HIGH 0x000001
63#define GPIO_INT_LVL_LEVEL_LOW 0x000000
64
65struct tegra_gpio_bank {
66 int bank;
67 int irq;
68 spinlock_t lvl_lock[4];
8939ddc7 69#ifdef CONFIG_PM_SLEEP
2e47b8b3
CC
70 u32 cnf[4];
71 u32 out[4];
72 u32 oe[4];
73 u32 int_enb[4];
74 u32 int_lvl[4];
75#endif
3c92db9a
EG
76};
77
bdc93a77 78static struct irq_domain *irq_domain;
88d8951e 79static void __iomem *regs;
3391811c 80static u32 tegra_gpio_bank_count;
5c1e2c9d
SW
81static u32 tegra_gpio_bank_stride;
82static u32 tegra_gpio_upper_offset;
3391811c 83static struct tegra_gpio_bank *tegra_gpio_banks;
88d8951e
SW
84
85static inline void tegra_gpio_writel(u32 val, u32 reg)
86{
87 __raw_writel(val, regs + reg);
88}
89
90static inline u32 tegra_gpio_readl(u32 reg)
91{
92 return __raw_readl(regs + reg);
93}
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EG
94
95static int tegra_gpio_compose(int bank, int port, int bit)
96{
97 return (bank << 5) | ((port & 0x3) << 3) | (bit & 0x7);
98}
99
100static void tegra_gpio_mask_write(u32 reg, int gpio, int value)
101{
102 u32 val;
103
104 val = 0x100 << GPIO_BIT(gpio);
105 if (value)
106 val |= 1 << GPIO_BIT(gpio);
88d8951e 107 tegra_gpio_writel(val, reg);
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EG
108}
109
3e215d0a 110static void tegra_gpio_enable(int gpio)
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EG
111{
112 tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1);
113}
114
3e215d0a 115static void tegra_gpio_disable(int gpio)
3c92db9a
EG
116{
117 tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0);
118}
119
924a0987 120static int tegra_gpio_request(struct gpio_chip *chip, unsigned offset)
3e215d0a
SW
121{
122 return pinctrl_request_gpio(offset);
123}
124
924a0987 125static void tegra_gpio_free(struct gpio_chip *chip, unsigned offset)
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SW
126{
127 pinctrl_free_gpio(offset);
128 tegra_gpio_disable(offset);
129}
130
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EG
131static void tegra_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
132{
133 tegra_gpio_mask_write(GPIO_MSK_OUT(offset), offset, value);
134}
135
136static int tegra_gpio_get(struct gpio_chip *chip, unsigned offset)
137{
195812e4
LD
138 /* If gpio is in output mode then read from the out value */
139 if ((tegra_gpio_readl(GPIO_OE(offset)) >> GPIO_BIT(offset)) & 1)
140 return (tegra_gpio_readl(GPIO_OUT(offset)) >>
141 GPIO_BIT(offset)) & 0x1;
142
88d8951e 143 return (tegra_gpio_readl(GPIO_IN(offset)) >> GPIO_BIT(offset)) & 0x1;
3c92db9a
EG
144}
145
146static int tegra_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
147{
148 tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 0);
3e215d0a 149 tegra_gpio_enable(offset);
3c92db9a
EG
150 return 0;
151}
152
153static int tegra_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
154 int value)
155{
156 tegra_gpio_set(chip, offset, value);
157 tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 1);
3e215d0a 158 tegra_gpio_enable(offset);
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EG
159 return 0;
160}
161
438a99c0
SW
162static int tegra_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
163{
bdc93a77 164 return irq_find_mapping(irq_domain, offset);
438a99c0 165}
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EG
166
167static struct gpio_chip tegra_gpio_chip = {
168 .label = "tegra-gpio",
3e215d0a
SW
169 .request = tegra_gpio_request,
170 .free = tegra_gpio_free,
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EG
171 .direction_input = tegra_gpio_direction_input,
172 .get = tegra_gpio_get,
173 .direction_output = tegra_gpio_direction_output,
174 .set = tegra_gpio_set,
438a99c0 175 .to_irq = tegra_gpio_to_irq,
3c92db9a 176 .base = 0,
3c92db9a
EG
177};
178
37337a8d 179static void tegra_gpio_irq_ack(struct irq_data *d)
3c92db9a 180{
6f74dc9b 181 int gpio = d->hwirq;
3c92db9a 182
88d8951e 183 tegra_gpio_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio));
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EG
184}
185
37337a8d 186static void tegra_gpio_irq_mask(struct irq_data *d)
3c92db9a 187{
6f74dc9b 188 int gpio = d->hwirq;
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EG
189
190 tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0);
191}
192
37337a8d 193static void tegra_gpio_irq_unmask(struct irq_data *d)
3c92db9a 194{
6f74dc9b 195 int gpio = d->hwirq;
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EG
196
197 tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 1);
198}
199
37337a8d 200static int tegra_gpio_irq_set_type(struct irq_data *d, unsigned int type)
3c92db9a 201{
6f74dc9b 202 int gpio = d->hwirq;
37337a8d 203 struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
3c92db9a
EG
204 int port = GPIO_PORT(gpio);
205 int lvl_type;
206 int val;
207 unsigned long flags;
208
209 switch (type & IRQ_TYPE_SENSE_MASK) {
210 case IRQ_TYPE_EDGE_RISING:
211 lvl_type = GPIO_INT_LVL_EDGE_RISING;
212 break;
213
214 case IRQ_TYPE_EDGE_FALLING:
215 lvl_type = GPIO_INT_LVL_EDGE_FALLING;
216 break;
217
218 case IRQ_TYPE_EDGE_BOTH:
219 lvl_type = GPIO_INT_LVL_EDGE_BOTH;
220 break;
221
222 case IRQ_TYPE_LEVEL_HIGH:
223 lvl_type = GPIO_INT_LVL_LEVEL_HIGH;
224 break;
225
226 case IRQ_TYPE_LEVEL_LOW:
227 lvl_type = GPIO_INT_LVL_LEVEL_LOW;
228 break;
229
230 default:
231 return -EINVAL;
232 }
233
234 spin_lock_irqsave(&bank->lvl_lock[port], flags);
235
88d8951e 236 val = tegra_gpio_readl(GPIO_INT_LVL(gpio));
3c92db9a
EG
237 val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio));
238 val |= lvl_type << GPIO_BIT(gpio);
88d8951e 239 tegra_gpio_writel(val, GPIO_INT_LVL(gpio));
3c92db9a
EG
240
241 spin_unlock_irqrestore(&bank->lvl_lock[port], flags);
242
d941136f
SW
243 tegra_gpio_mask_write(GPIO_MSK_OE(gpio), gpio, 0);
244 tegra_gpio_enable(gpio);
245
3c92db9a 246 if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
6845664a 247 __irq_set_handler_locked(d->irq, handle_level_irq);
3c92db9a 248 else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
6845664a 249 __irq_set_handler_locked(d->irq, handle_edge_irq);
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EG
250
251 return 0;
252}
253
254static void tegra_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
255{
256 struct tegra_gpio_bank *bank;
257 int port;
258 int pin;
259 int unmasked = 0;
98022940 260 struct irq_chip *chip = irq_desc_get_chip(desc);
3c92db9a 261
98022940 262 chained_irq_enter(chip, desc);
3c92db9a 263
6845664a 264 bank = irq_get_handler_data(irq);
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EG
265
266 for (port = 0; port < 4; port++) {
267 int gpio = tegra_gpio_compose(bank->bank, port, 0);
88d8951e
SW
268 unsigned long sta = tegra_gpio_readl(GPIO_INT_STA(gpio)) &
269 tegra_gpio_readl(GPIO_INT_ENB(gpio));
270 u32 lvl = tegra_gpio_readl(GPIO_INT_LVL(gpio));
3c92db9a
EG
271
272 for_each_set_bit(pin, &sta, 8) {
88d8951e 273 tegra_gpio_writel(1 << pin, GPIO_INT_CLR(gpio));
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EG
274
275 /* if gpio is edge triggered, clear condition
276 * before executing the hander so that we don't
277 * miss edges
278 */
279 if (lvl & (0x100 << pin)) {
280 unmasked = 1;
98022940 281 chained_irq_exit(chip, desc);
3c92db9a
EG
282 }
283
284 generic_handle_irq(gpio_to_irq(gpio + pin));
285 }
286 }
287
288 if (!unmasked)
98022940 289 chained_irq_exit(chip, desc);
3c92db9a
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290
291}
292
8939ddc7
LD
293#ifdef CONFIG_PM_SLEEP
294static int tegra_gpio_resume(struct device *dev)
2e47b8b3
CC
295{
296 unsigned long flags;
c8309ef6
CC
297 int b;
298 int p;
2e47b8b3
CC
299
300 local_irq_save(flags);
301
3391811c 302 for (b = 0; b < tegra_gpio_bank_count; b++) {
2e47b8b3
CC
303 struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];
304
305 for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
306 unsigned int gpio = (b<<5) | (p<<3);
88d8951e
SW
307 tegra_gpio_writel(bank->cnf[p], GPIO_CNF(gpio));
308 tegra_gpio_writel(bank->out[p], GPIO_OUT(gpio));
309 tegra_gpio_writel(bank->oe[p], GPIO_OE(gpio));
310 tegra_gpio_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio));
311 tegra_gpio_writel(bank->int_enb[p], GPIO_INT_ENB(gpio));
2e47b8b3
CC
312 }
313 }
314
315 local_irq_restore(flags);
8939ddc7 316 return 0;
2e47b8b3
CC
317}
318
8939ddc7 319static int tegra_gpio_suspend(struct device *dev)
2e47b8b3
CC
320{
321 unsigned long flags;
c8309ef6
CC
322 int b;
323 int p;
2e47b8b3 324
2e47b8b3 325 local_irq_save(flags);
3391811c 326 for (b = 0; b < tegra_gpio_bank_count; b++) {
2e47b8b3
CC
327 struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];
328
329 for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
330 unsigned int gpio = (b<<5) | (p<<3);
88d8951e
SW
331 bank->cnf[p] = tegra_gpio_readl(GPIO_CNF(gpio));
332 bank->out[p] = tegra_gpio_readl(GPIO_OUT(gpio));
333 bank->oe[p] = tegra_gpio_readl(GPIO_OE(gpio));
334 bank->int_enb[p] = tegra_gpio_readl(GPIO_INT_ENB(gpio));
335 bank->int_lvl[p] = tegra_gpio_readl(GPIO_INT_LVL(gpio));
2e47b8b3
CC
336 }
337 }
338 local_irq_restore(flags);
8939ddc7 339 return 0;
2e47b8b3
CC
340}
341
37337a8d 342static int tegra_gpio_wake_enable(struct irq_data *d, unsigned int enable)
2e47b8b3 343{
37337a8d 344 struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
6845664a 345 return irq_set_irq_wake(bank->irq, enable);
2e47b8b3
CC
346}
347#endif
3c92db9a
EG
348
349static struct irq_chip tegra_gpio_irq_chip = {
350 .name = "GPIO",
37337a8d
LB
351 .irq_ack = tegra_gpio_irq_ack,
352 .irq_mask = tegra_gpio_irq_mask,
353 .irq_unmask = tegra_gpio_irq_unmask,
354 .irq_set_type = tegra_gpio_irq_set_type,
8939ddc7 355#ifdef CONFIG_PM_SLEEP
37337a8d 356 .irq_set_wake = tegra_gpio_wake_enable,
2e47b8b3 357#endif
3c92db9a
EG
358};
359
8939ddc7
LD
360static const struct dev_pm_ops tegra_gpio_pm_ops = {
361 SET_SYSTEM_SLEEP_PM_OPS(tegra_gpio_suspend, tegra_gpio_resume)
362};
363
5c1e2c9d
SW
364struct tegra_gpio_soc_config {
365 u32 bank_stride;
366 u32 upper_offset;
367};
368
369static struct tegra_gpio_soc_config tegra20_gpio_config = {
370 .bank_stride = 0x80,
371 .upper_offset = 0x800,
372};
373
374static struct tegra_gpio_soc_config tegra30_gpio_config = {
375 .bank_stride = 0x100,
376 .upper_offset = 0x80,
377};
378
aeca8ad1 379static struct of_device_id tegra_gpio_of_match[] = {
5c1e2c9d
SW
380 { .compatible = "nvidia,tegra30-gpio", .data = &tegra30_gpio_config },
381 { .compatible = "nvidia,tegra20-gpio", .data = &tegra20_gpio_config },
382 { },
383};
3c92db9a
EG
384
385/* This lock class tells lockdep that GPIO irqs are in a different
386 * category than their parents, so it won't report false recursion.
387 */
388static struct lock_class_key gpio_lock_class;
389
3836309d 390static int tegra_gpio_probe(struct platform_device *pdev)
3c92db9a 391{
5c1e2c9d
SW
392 const struct of_device_id *match;
393 struct tegra_gpio_soc_config *config;
88d8951e 394 struct resource *res;
3c92db9a 395 struct tegra_gpio_bank *bank;
47008001 396 int gpio;
3c92db9a
EG
397 int i;
398 int j;
399
5c1e2c9d
SW
400 match = of_match_device(tegra_gpio_of_match, &pdev->dev);
401 if (match)
402 config = (struct tegra_gpio_soc_config *)match->data;
403 else
404 config = &tegra20_gpio_config;
405
406 tegra_gpio_bank_stride = config->bank_stride;
407 tegra_gpio_upper_offset = config->upper_offset;
408
3391811c
SW
409 for (;;) {
410 res = platform_get_resource(pdev, IORESOURCE_IRQ, tegra_gpio_bank_count);
411 if (!res)
412 break;
413 tegra_gpio_bank_count++;
414 }
415 if (!tegra_gpio_bank_count) {
416 dev_err(&pdev->dev, "Missing IRQ resource\n");
417 return -ENODEV;
418 }
419
420 tegra_gpio_chip.ngpio = tegra_gpio_bank_count * 32;
421
422 tegra_gpio_banks = devm_kzalloc(&pdev->dev,
423 tegra_gpio_bank_count * sizeof(*tegra_gpio_banks),
424 GFP_KERNEL);
425 if (!tegra_gpio_banks) {
426 dev_err(&pdev->dev, "Couldn't allocate bank structure\n");
427 return -ENODEV;
428 }
429
d0235677
LW
430 irq_domain = irq_domain_add_linear(pdev->dev.of_node,
431 tegra_gpio_chip.ngpio,
bdc93a77 432 &irq_domain_simple_ops, NULL);
d0235677
LW
433 if (!irq_domain)
434 return -ENODEV;
6f74dc9b 435
3391811c 436 for (i = 0; i < tegra_gpio_bank_count; i++) {
88d8951e
SW
437 res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
438 if (!res) {
439 dev_err(&pdev->dev, "Missing IRQ resource\n");
440 return -ENODEV;
441 }
442
443 bank = &tegra_gpio_banks[i];
444 bank->bank = i;
445 bank->irq = res->start;
446 }
447
448 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
449 if (!res) {
450 dev_err(&pdev->dev, "Missing MEM resource\n");
451 return -ENODEV;
452 }
453
641d0342
TR
454 regs = devm_ioremap_resource(&pdev->dev, res);
455 if (IS_ERR(regs))
456 return PTR_ERR(regs);
88d8951e 457
4a3398ee 458 for (i = 0; i < tegra_gpio_bank_count; i++) {
3c92db9a
EG
459 for (j = 0; j < 4; j++) {
460 int gpio = tegra_gpio_compose(i, j, 0);
88d8951e 461 tegra_gpio_writel(0x00, GPIO_INT_ENB(gpio));
3c92db9a
EG
462 }
463 }
464
df221227 465#ifdef CONFIG_OF_GPIO
88d8951e
SW
466 tegra_gpio_chip.of_node = pdev->dev.of_node;
467#endif
df221227 468
3c92db9a
EG
469 gpiochip_add(&tegra_gpio_chip);
470
3391811c 471 for (gpio = 0; gpio < tegra_gpio_chip.ngpio; gpio++) {
d0235677 472 int irq = irq_create_mapping(irq_domain, gpio);
47008001 473 /* No validity check; all Tegra GPIOs are valid IRQs */
3c92db9a 474
47008001 475 bank = &tegra_gpio_banks[GPIO_BANK(gpio)];
3c92db9a 476
47008001
SW
477 irq_set_lockdep_class(irq, &gpio_lock_class);
478 irq_set_chip_data(irq, bank);
479 irq_set_chip_and_handler(irq, &tegra_gpio_irq_chip,
f38c02f3 480 handle_simple_irq);
47008001 481 set_irq_flags(irq, IRQF_VALID);
3c92db9a
EG
482 }
483
3391811c 484 for (i = 0; i < tegra_gpio_bank_count; i++) {
3c92db9a
EG
485 bank = &tegra_gpio_banks[i];
486
6845664a
TG
487 irq_set_chained_handler(bank->irq, tegra_gpio_irq_handler);
488 irq_set_handler_data(bank->irq, bank);
3c92db9a
EG
489
490 for (j = 0; j < 4; j++)
491 spin_lock_init(&bank->lvl_lock[j]);
492 }
493
494 return 0;
495}
496
88d8951e
SW
497static struct platform_driver tegra_gpio_driver = {
498 .driver = {
499 .name = "tegra-gpio",
500 .owner = THIS_MODULE,
8939ddc7 501 .pm = &tegra_gpio_pm_ops,
88d8951e
SW
502 .of_match_table = tegra_gpio_of_match,
503 },
504 .probe = tegra_gpio_probe,
505};
506
507static int __init tegra_gpio_init(void)
508{
509 return platform_driver_register(&tegra_gpio_driver);
510}
3c92db9a
EG
511postcore_initcall(tegra_gpio_init);
512
513#ifdef CONFIG_DEBUG_FS
514
515#include <linux/debugfs.h>
516#include <linux/seq_file.h>
517
518static int dbg_gpio_show(struct seq_file *s, void *unused)
519{
520 int i;
521 int j;
522
4a3398ee 523 for (i = 0; i < tegra_gpio_bank_count; i++) {
3c92db9a
EG
524 for (j = 0; j < 4; j++) {
525 int gpio = tegra_gpio_compose(i, j, 0);
2e47b8b3
CC
526 seq_printf(s,
527 "%d:%d %02x %02x %02x %02x %02x %02x %06x\n",
528 i, j,
88d8951e
SW
529 tegra_gpio_readl(GPIO_CNF(gpio)),
530 tegra_gpio_readl(GPIO_OE(gpio)),
531 tegra_gpio_readl(GPIO_OUT(gpio)),
532 tegra_gpio_readl(GPIO_IN(gpio)),
533 tegra_gpio_readl(GPIO_INT_STA(gpio)),
534 tegra_gpio_readl(GPIO_INT_ENB(gpio)),
535 tegra_gpio_readl(GPIO_INT_LVL(gpio)));
3c92db9a
EG
536 }
537 }
538 return 0;
539}
540
541static int dbg_gpio_open(struct inode *inode, struct file *file)
542{
543 return single_open(file, dbg_gpio_show, &inode->i_private);
544}
545
546static const struct file_operations debug_fops = {
547 .open = dbg_gpio_open,
548 .read = seq_read,
549 .llseek = seq_lseek,
550 .release = single_release,
551};
552
553static int __init tegra_gpio_debuginit(void)
554{
555 (void) debugfs_create_file("tegra_gpio", S_IRUGO,
556 NULL, NULL, &debug_fops);
557 return 0;
558}
559late_initcall(tegra_gpio_debuginit);
560#endif