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1/*
2 * linux/arch/arm/mach-at91/gpio.c
3 *
4 * Copyright (C) 2005 HP Labs
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12#include <linux/clk.h>
13#include <linux/errno.h>
14#include <linux/device.h>
15#include <linux/gpio.h>
16#include <linux/interrupt.h>
17#include <linux/irq.h>
18#include <linux/debugfs.h>
19#include <linux/seq_file.h>
20#include <linux/kernel.h>
21#include <linux/list.h>
22#include <linux/module.h>
23#include <linux/io.h>
24#include <linux/irqdomain.h>
25#include <linux/irqchip/chained_irq.h>
26#include <linux/of_address.h>
27
28#include <mach/hardware.h>
29#include <mach/at91_pio.h>
30
31#include "generic.h"
32
33#define MAX_NB_GPIO_PER_BANK 32
34
35struct at91_gpio_chip {
36 struct gpio_chip chip;
37 struct at91_gpio_chip *next; /* Bank sharing same clock */
38 int pioc_hwirq; /* PIO bank interrupt identifier on AIC */
39 int pioc_virq; /* PIO bank Linux virtual interrupt */
40 int pioc_idx; /* PIO bank index */
41 void __iomem *regbase; /* PIO bank virtual address */
42 struct clk *clock; /* associated clock */
43 struct irq_domain *domain; /* associated irq domain */
44};
45
46#define to_at91_gpio_chip(c) container_of(c, struct at91_gpio_chip, chip)
47
48static int at91_gpiolib_request(struct gpio_chip *chip, unsigned offset);
49static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip);
50static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val);
51static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset);
52static int at91_gpiolib_direction_output(struct gpio_chip *chip,
53 unsigned offset, int val);
54static int at91_gpiolib_direction_input(struct gpio_chip *chip,
55 unsigned offset);
56static int at91_gpiolib_to_irq(struct gpio_chip *chip, unsigned offset);
57
58#define AT91_GPIO_CHIP(name) \
59 { \
60 .chip = { \
61 .label = name, \
62 .request = at91_gpiolib_request, \
63 .direction_input = at91_gpiolib_direction_input, \
64 .direction_output = at91_gpiolib_direction_output, \
65 .get = at91_gpiolib_get, \
66 .set = at91_gpiolib_set, \
67 .dbg_show = at91_gpiolib_dbg_show, \
68 .to_irq = at91_gpiolib_to_irq, \
69 .ngpio = MAX_NB_GPIO_PER_BANK, \
70 }, \
71 }
72
73static struct at91_gpio_chip gpio_chip[] = {
74 AT91_GPIO_CHIP("pioA"),
75 AT91_GPIO_CHIP("pioB"),
76 AT91_GPIO_CHIP("pioC"),
77 AT91_GPIO_CHIP("pioD"),
78 AT91_GPIO_CHIP("pioE"),
79};
80
81static int gpio_banks;
82static unsigned long at91_gpio_caps;
83
84/* All PIO controllers support PIO3 features */
85#define AT91_GPIO_CAP_PIO3 (1 << 0)
86
87#define has_pio3() (at91_gpio_caps & AT91_GPIO_CAP_PIO3)
88
89/*--------------------------------------------------------------------------*/
90
91static inline void __iomem *pin_to_controller(unsigned pin)
92{
93 pin /= MAX_NB_GPIO_PER_BANK;
94 if (likely(pin < gpio_banks))
95 return gpio_chip[pin].regbase;
96
97 return NULL;
98}
99
100static inline unsigned pin_to_mask(unsigned pin)
101{
102 return 1 << (pin % MAX_NB_GPIO_PER_BANK);
103}
104
105
106static char peripheral_function(void __iomem *pio, unsigned mask)
107{
108 char ret = 'X';
109 u8 select;
110
111 if (pio) {
112 if (has_pio3()) {
113 select = !!(__raw_readl(pio + PIO_ABCDSR1) & mask);
114 select |= (!!(__raw_readl(pio + PIO_ABCDSR2) & mask) << 1);
115 ret = 'A' + select;
116 } else {
117 ret = __raw_readl(pio + PIO_ABSR) & mask ?
118 'B' : 'A';
119 }
120 }
121
122 return ret;
123}
124
125/*--------------------------------------------------------------------------*/
126
127/* Not all hardware capabilities are exposed through these calls; they
128 * only encapsulate the most common features and modes. (So if you
129 * want to change signals in groups, do it directly.)
130 *
131 * Bootloaders will usually handle some of the pin multiplexing setup.
132 * The intent is certainly that by the time Linux is fully booted, all
133 * pins should have been fully initialized. These setup calls should
134 * only be used by board setup routines, or possibly in driver probe().
135 *
136 * For bootloaders doing all that setup, these calls could be inlined
137 * as NOPs so Linux won't duplicate any setup code
138 */
139
140
141/*
142 * mux the pin to the "GPIO" peripheral role.
143 */
144int __init_or_module at91_set_GPIO_periph(unsigned pin, int use_pullup)
145{
146 void __iomem *pio = pin_to_controller(pin);
147 unsigned mask = pin_to_mask(pin);
148
149 if (!pio)
150 return -EINVAL;
151 __raw_writel(mask, pio + PIO_IDR);
152 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
153 __raw_writel(mask, pio + PIO_PER);
154 return 0;
155}
156EXPORT_SYMBOL(at91_set_GPIO_periph);
157
158
159/*
160 * mux the pin to the "A" internal peripheral role.
161 */
162int __init_or_module at91_set_A_periph(unsigned pin, int use_pullup)
163{
164 void __iomem *pio = pin_to_controller(pin);
165 unsigned mask = pin_to_mask(pin);
166
167 if (!pio)
168 return -EINVAL;
169
170 __raw_writel(mask, pio + PIO_IDR);
171 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
172 if (has_pio3()) {
173 __raw_writel(__raw_readl(pio + PIO_ABCDSR1) & ~mask,
174 pio + PIO_ABCDSR1);
175 __raw_writel(__raw_readl(pio + PIO_ABCDSR2) & ~mask,
176 pio + PIO_ABCDSR2);
177 } else {
178 __raw_writel(mask, pio + PIO_ASR);
179 }
180 __raw_writel(mask, pio + PIO_PDR);
181 return 0;
182}
183EXPORT_SYMBOL(at91_set_A_periph);
184
185
186/*
187 * mux the pin to the "B" internal peripheral role.
188 */
189int __init_or_module at91_set_B_periph(unsigned pin, int use_pullup)
190{
191 void __iomem *pio = pin_to_controller(pin);
192 unsigned mask = pin_to_mask(pin);
193
194 if (!pio)
195 return -EINVAL;
196
197 __raw_writel(mask, pio + PIO_IDR);
198 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
199 if (has_pio3()) {
200 __raw_writel(__raw_readl(pio + PIO_ABCDSR1) | mask,
201 pio + PIO_ABCDSR1);
202 __raw_writel(__raw_readl(pio + PIO_ABCDSR2) & ~mask,
203 pio + PIO_ABCDSR2);
204 } else {
205 __raw_writel(mask, pio + PIO_BSR);
206 }
207 __raw_writel(mask, pio + PIO_PDR);
208 return 0;
209}
210EXPORT_SYMBOL(at91_set_B_periph);
211
212
213/*
214 * mux the pin to the "C" internal peripheral role.
215 */
216int __init_or_module at91_set_C_periph(unsigned pin, int use_pullup)
217{
218 void __iomem *pio = pin_to_controller(pin);
219 unsigned mask = pin_to_mask(pin);
220
221 if (!pio || !has_pio3())
222 return -EINVAL;
223
224 __raw_writel(mask, pio + PIO_IDR);
225 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
226 __raw_writel(__raw_readl(pio + PIO_ABCDSR1) & ~mask, pio + PIO_ABCDSR1);
227 __raw_writel(__raw_readl(pio + PIO_ABCDSR2) | mask, pio + PIO_ABCDSR2);
228 __raw_writel(mask, pio + PIO_PDR);
229 return 0;
230}
231EXPORT_SYMBOL(at91_set_C_periph);
232
233
234/*
235 * mux the pin to the "D" internal peripheral role.
236 */
237int __init_or_module at91_set_D_periph(unsigned pin, int use_pullup)
238{
239 void __iomem *pio = pin_to_controller(pin);
240 unsigned mask = pin_to_mask(pin);
241
242 if (!pio || !has_pio3())
243 return -EINVAL;
244
245 __raw_writel(mask, pio + PIO_IDR);
246 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
247 __raw_writel(__raw_readl(pio + PIO_ABCDSR1) | mask, pio + PIO_ABCDSR1);
248 __raw_writel(__raw_readl(pio + PIO_ABCDSR2) | mask, pio + PIO_ABCDSR2);
249 __raw_writel(mask, pio + PIO_PDR);
250 return 0;
251}
252EXPORT_SYMBOL(at91_set_D_periph);
253
254
255/*
256 * mux the pin to the gpio controller (instead of "A", "B", "C"
257 * or "D" peripheral), and configure it for an input.
258 */
259int __init_or_module at91_set_gpio_input(unsigned pin, int use_pullup)
260{
261 void __iomem *pio = pin_to_controller(pin);
262 unsigned mask = pin_to_mask(pin);
263
264 if (!pio)
265 return -EINVAL;
266
267 __raw_writel(mask, pio + PIO_IDR);
268 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
269 __raw_writel(mask, pio + PIO_ODR);
270 __raw_writel(mask, pio + PIO_PER);
271 return 0;
272}
273EXPORT_SYMBOL(at91_set_gpio_input);
274
275
276/*
277 * mux the pin to the gpio controller (instead of "A", "B", "C"
278 * or "D" peripheral), and configure it for an output.
279 */
280int __init_or_module at91_set_gpio_output(unsigned pin, int value)
281{
282 void __iomem *pio = pin_to_controller(pin);
283 unsigned mask = pin_to_mask(pin);
284
285 if (!pio)
286 return -EINVAL;
287
288 __raw_writel(mask, pio + PIO_IDR);
289 __raw_writel(mask, pio + PIO_PUDR);
290 __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
291 __raw_writel(mask, pio + PIO_OER);
292 __raw_writel(mask, pio + PIO_PER);
293 return 0;
294}
295EXPORT_SYMBOL(at91_set_gpio_output);
296
297
298/*
299 * enable/disable the glitch filter; mostly used with IRQ handling.
300 */
301int __init_or_module at91_set_deglitch(unsigned pin, int is_on)
302{
303 void __iomem *pio = pin_to_controller(pin);
304 unsigned mask = pin_to_mask(pin);
305
306 if (!pio)
307 return -EINVAL;
308
309 if (has_pio3() && is_on)
310 __raw_writel(mask, pio + PIO_IFSCDR);
311 __raw_writel(mask, pio + (is_on ? PIO_IFER : PIO_IFDR));
312 return 0;
313}
314EXPORT_SYMBOL(at91_set_deglitch);
315
316/*
317 * enable/disable the debounce filter;
318 */
319int __init_or_module at91_set_debounce(unsigned pin, int is_on, int div)
320{
321 void __iomem *pio = pin_to_controller(pin);
322 unsigned mask = pin_to_mask(pin);
323
324 if (!pio || !has_pio3())
325 return -EINVAL;
326
327 if (is_on) {
328 __raw_writel(mask, pio + PIO_IFSCER);
329 __raw_writel(div & PIO_SCDR_DIV, pio + PIO_SCDR);
330 __raw_writel(mask, pio + PIO_IFER);
331 } else {
332 __raw_writel(mask, pio + PIO_IFDR);
333 }
334 return 0;
335}
336EXPORT_SYMBOL(at91_set_debounce);
337
338/*
339 * enable/disable the multi-driver; This is only valid for output and
340 * allows the output pin to run as an open collector output.
341 */
342int __init_or_module at91_set_multi_drive(unsigned pin, int is_on)
343{
344 void __iomem *pio = pin_to_controller(pin);
345 unsigned mask = pin_to_mask(pin);
346
347 if (!pio)
348 return -EINVAL;
349
350 __raw_writel(mask, pio + (is_on ? PIO_MDER : PIO_MDDR));
351 return 0;
352}
353EXPORT_SYMBOL(at91_set_multi_drive);
354
355/*
356 * enable/disable the pull-down.
357 * If pull-up already enabled while calling the function, we disable it.
358 */
359int __init_or_module at91_set_pulldown(unsigned pin, int is_on)
360{
361 void __iomem *pio = pin_to_controller(pin);
362 unsigned mask = pin_to_mask(pin);
363
364 if (!pio || !has_pio3())
365 return -EINVAL;
366
367 /* Disable pull-up anyway */
368 __raw_writel(mask, pio + PIO_PUDR);
369 __raw_writel(mask, pio + (is_on ? PIO_PPDER : PIO_PPDDR));
370 return 0;
371}
372EXPORT_SYMBOL(at91_set_pulldown);
373
374/*
375 * disable Schmitt trigger
376 */
377int __init_or_module at91_disable_schmitt_trig(unsigned pin)
378{
379 void __iomem *pio = pin_to_controller(pin);
380 unsigned mask = pin_to_mask(pin);
381
382 if (!pio || !has_pio3())
383 return -EINVAL;
384
385 __raw_writel(__raw_readl(pio + PIO_SCHMITT) | mask, pio + PIO_SCHMITT);
386 return 0;
387}
388EXPORT_SYMBOL(at91_disable_schmitt_trig);
389
390/*
391 * assuming the pin is muxed as a gpio output, set its value.
392 */
393int at91_set_gpio_value(unsigned pin, int value)
394{
395 void __iomem *pio = pin_to_controller(pin);
396 unsigned mask = pin_to_mask(pin);
397
398 if (!pio)
399 return -EINVAL;
400 __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
401 return 0;
402}
403EXPORT_SYMBOL(at91_set_gpio_value);
404
405
406/*
407 * read the pin's value (works even if it's not muxed as a gpio).
408 */
409int at91_get_gpio_value(unsigned pin)
410{
411 void __iomem *pio = pin_to_controller(pin);
412 unsigned mask = pin_to_mask(pin);
413 u32 pdsr;
414
415 if (!pio)
416 return -EINVAL;
417 pdsr = __raw_readl(pio + PIO_PDSR);
418 return (pdsr & mask) != 0;
419}
420EXPORT_SYMBOL(at91_get_gpio_value);
421
422/*--------------------------------------------------------------------------*/
423
424#ifdef CONFIG_PM
425
426static u32 wakeups[MAX_GPIO_BANKS];
427static u32 backups[MAX_GPIO_BANKS];
428
429static int gpio_irq_set_wake(struct irq_data *d, unsigned state)
430{
431 struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
432 unsigned mask = 1 << d->hwirq;
433 unsigned bank = at91_gpio->pioc_idx;
434
435 if (unlikely(bank >= MAX_GPIO_BANKS))
436 return -EINVAL;
437
438 if (state)
439 wakeups[bank] |= mask;
440 else
441 wakeups[bank] &= ~mask;
442
443 irq_set_irq_wake(at91_gpio->pioc_virq, state);
444
445 return 0;
446}
447
448void at91_gpio_suspend(void)
449{
450 int i;
451
452 for (i = 0; i < gpio_banks; i++) {
453 void __iomem *pio = gpio_chip[i].regbase;
454
455 backups[i] = __raw_readl(pio + PIO_IMR);
456 __raw_writel(backups[i], pio + PIO_IDR);
457 __raw_writel(wakeups[i], pio + PIO_IER);
458
459 if (!wakeups[i]) {
460 clk_unprepare(gpio_chip[i].clock);
461 clk_disable(gpio_chip[i].clock);
462 } else {
463#ifdef CONFIG_PM_DEBUG
464 printk(KERN_DEBUG "GPIO-%c may wake for %08x\n", 'A'+i, wakeups[i]);
465#endif
466 }
467 }
468}
469
470void at91_gpio_resume(void)
471{
472 int i;
473
474 for (i = 0; i < gpio_banks; i++) {
475 void __iomem *pio = gpio_chip[i].regbase;
476
477 if (!wakeups[i]) {
478 if (clk_prepare(gpio_chip[i].clock) == 0)
479 clk_enable(gpio_chip[i].clock);
480 }
481
482 __raw_writel(wakeups[i], pio + PIO_IDR);
483 __raw_writel(backups[i], pio + PIO_IER);
484 }
485}
486
487#else
488#define gpio_irq_set_wake NULL
489#endif
490
491
492/* Several AIC controller irqs are dispatched through this GPIO handler.
493 * To use any AT91_PIN_* as an externally triggered IRQ, first call
494 * at91_set_gpio_input() then maybe enable its glitch filter.
495 * Then just request_irq() with the pin ID; it works like any ARM IRQ
496 * handler.
497 * First implementation always triggers on rising and falling edges
498 * whereas the newer PIO3 can be additionally configured to trigger on
499 * level, edge with any polarity.
500 *
501 * Alternatively, certain pins may be used directly as IRQ0..IRQ6 after
502 * configuring them with at91_set_a_periph() or at91_set_b_periph().
503 * IRQ0..IRQ6 should be configurable, e.g. level vs edge triggering.
504 */
505
506static void gpio_irq_mask(struct irq_data *d)
507{
508 struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
509 void __iomem *pio = at91_gpio->regbase;
510 unsigned mask = 1 << d->hwirq;
511
512 if (pio)
513 __raw_writel(mask, pio + PIO_IDR);
514}
515
516static void gpio_irq_unmask(struct irq_data *d)
517{
518 struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
519 void __iomem *pio = at91_gpio->regbase;
520 unsigned mask = 1 << d->hwirq;
521
522 if (pio)
523 __raw_writel(mask, pio + PIO_IER);
524}
525
526static int gpio_irq_type(struct irq_data *d, unsigned type)
527{
528 switch (type) {
529 case IRQ_TYPE_NONE:
530 case IRQ_TYPE_EDGE_BOTH:
531 return 0;
532 default:
533 return -EINVAL;
534 }
535}
536
537/* Alternate irq type for PIO3 support */
538static int alt_gpio_irq_type(struct irq_data *d, unsigned type)
539{
540 struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
541 void __iomem *pio = at91_gpio->regbase;
542 unsigned mask = 1 << d->hwirq;
543
544 switch (type) {
545 case IRQ_TYPE_EDGE_RISING:
546 __raw_writel(mask, pio + PIO_ESR);
547 __raw_writel(mask, pio + PIO_REHLSR);
548 break;
549 case IRQ_TYPE_EDGE_FALLING:
550 __raw_writel(mask, pio + PIO_ESR);
551 __raw_writel(mask, pio + PIO_FELLSR);
552 break;
553 case IRQ_TYPE_LEVEL_LOW:
554 __raw_writel(mask, pio + PIO_LSR);
555 __raw_writel(mask, pio + PIO_FELLSR);
556 break;
557 case IRQ_TYPE_LEVEL_HIGH:
558 __raw_writel(mask, pio + PIO_LSR);
559 __raw_writel(mask, pio + PIO_REHLSR);
560 break;
561 case IRQ_TYPE_EDGE_BOTH:
562 /*
563 * disable additional interrupt modes:
564 * fall back to default behavior
565 */
566 __raw_writel(mask, pio + PIO_AIMDR);
567 return 0;
568 case IRQ_TYPE_NONE:
569 default:
570 pr_warn("AT91: No type for irq %d\n", gpio_to_irq(d->irq));
571 return -EINVAL;
572 }
573
574 /* enable additional interrupt modes */
575 __raw_writel(mask, pio + PIO_AIMER);
576
577 return 0;
578}
579
580static struct irq_chip gpio_irqchip = {
581 .name = "GPIO",
582 .irq_disable = gpio_irq_mask,
583 .irq_mask = gpio_irq_mask,
584 .irq_unmask = gpio_irq_unmask,
585 /* .irq_set_type is set dynamically */
586 .irq_set_wake = gpio_irq_set_wake,
587};
588
589static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
590{
591 struct irq_chip *chip = irq_desc_get_chip(desc);
592 struct irq_data *idata = irq_desc_get_irq_data(desc);
593 struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(idata);
594 void __iomem *pio = at91_gpio->regbase;
595 unsigned long isr;
596 int n;
597
598 chained_irq_enter(chip, desc);
599 for (;;) {
600 /* Reading ISR acks pending (edge triggered) GPIO interrupts.
601 * When there none are pending, we're finished unless we need
602 * to process multiple banks (like ID_PIOCDE on sam9263).
603 */
604 isr = __raw_readl(pio + PIO_ISR) & __raw_readl(pio + PIO_IMR);
605 if (!isr) {
606 if (!at91_gpio->next)
607 break;
608 at91_gpio = at91_gpio->next;
609 pio = at91_gpio->regbase;
610 continue;
611 }
612
613 n = find_first_bit(&isr, BITS_PER_LONG);
614 while (n < BITS_PER_LONG) {
615 generic_handle_irq(irq_find_mapping(at91_gpio->domain, n));
616 n = find_next_bit(&isr, BITS_PER_LONG, n + 1);
617 }
618 }
619 chained_irq_exit(chip, desc);
620 /* now it may re-trigger */
621}
622
623/*--------------------------------------------------------------------------*/
624
625#ifdef CONFIG_DEBUG_FS
626
627static void gpio_printf(struct seq_file *s, void __iomem *pio, unsigned mask)
628{
629 char *trigger = NULL;
630 char *polarity = NULL;
631
632 if (__raw_readl(pio + PIO_IMR) & mask) {
633 if (!has_pio3() || !(__raw_readl(pio + PIO_AIMMR) & mask )) {
634 trigger = "edge";
635 polarity = "both";
636 } else {
637 if (__raw_readl(pio + PIO_ELSR) & mask) {
638 trigger = "level";
639 polarity = __raw_readl(pio + PIO_FRLHSR) & mask ?
640 "high" : "low";
641 } else {
642 trigger = "edge";
643 polarity = __raw_readl(pio + PIO_FRLHSR) & mask ?
644 "rising" : "falling";
645 }
646 }
647 seq_printf(s, "IRQ:%s-%s\t", trigger, polarity);
648 } else {
649 seq_printf(s, "GPIO:%s\t\t",
650 __raw_readl(pio + PIO_PDSR) & mask ? "1" : "0");
651 }
652}
653
654static int at91_gpio_show(struct seq_file *s, void *unused)
655{
656 int bank, j;
657
658 /* print heading */
659 seq_printf(s, "Pin\t");
660 for (bank = 0; bank < gpio_banks; bank++) {
661 seq_printf(s, "PIO%c\t\t", 'A' + bank);
662 };
663 seq_printf(s, "\n\n");
664
665 /* print pin status */
666 for (j = 0; j < 32; j++) {
667 seq_printf(s, "%i:\t", j);
668
669 for (bank = 0; bank < gpio_banks; bank++) {
670 unsigned pin = (32 * bank) + j;
671 void __iomem *pio = pin_to_controller(pin);
672 unsigned mask = pin_to_mask(pin);
673
674 if (__raw_readl(pio + PIO_PSR) & mask)
675 gpio_printf(s, pio, mask);
676 else
677 seq_printf(s, "%c\t\t",
678 peripheral_function(pio, mask));
679 }
680
681 seq_printf(s, "\n");
682 }
683
684 return 0;
685}
686
687static int at91_gpio_open(struct inode *inode, struct file *file)
688{
689 return single_open(file, at91_gpio_show, NULL);
690}
691
692static const struct file_operations at91_gpio_operations = {
693 .open = at91_gpio_open,
694 .read = seq_read,
695 .llseek = seq_lseek,
696 .release = single_release,
697};
698
699static int __init at91_gpio_debugfs_init(void)
700{
701 /* /sys/kernel/debug/at91_gpio */
702 (void) debugfs_create_file("at91_gpio", S_IFREG | S_IRUGO, NULL, NULL, &at91_gpio_operations);
703 return 0;
704}
705postcore_initcall(at91_gpio_debugfs_init);
706
707#endif
708
709/*--------------------------------------------------------------------------*/
710
711/*
712 * This lock class tells lockdep that GPIO irqs are in a different
713 * category than their parents, so it won't report false recursion.
714 */
715static struct lock_class_key gpio_lock_class;
716
717/*
718 * irqdomain initialization: pile up irqdomains on top of AIC range
719 */
720static void __init at91_gpio_irqdomain(struct at91_gpio_chip *at91_gpio)
721{
722 int irq_base;
723
724 irq_base = irq_alloc_descs(-1, 0, at91_gpio->chip.ngpio, 0);
725 if (irq_base < 0)
726 panic("at91_gpio.%d: error %d: couldn't allocate IRQ numbers.\n",
727 at91_gpio->pioc_idx, irq_base);
728 at91_gpio->domain = irq_domain_add_legacy(NULL, at91_gpio->chip.ngpio,
729 irq_base, 0,
730 &irq_domain_simple_ops, NULL);
731 if (!at91_gpio->domain)
732 panic("at91_gpio.%d: couldn't allocate irq domain.\n",
733 at91_gpio->pioc_idx);
734}
735
736/*
737 * Called from the processor-specific init to enable GPIO interrupt support.
738 */
739void __init at91_gpio_irq_setup(void)
740{
741 unsigned pioc;
742 int gpio_irqnbr = 0;
743 struct at91_gpio_chip *this, *prev;
744
745 /* Setup proper .irq_set_type function */
746 if (has_pio3())
747 gpio_irqchip.irq_set_type = alt_gpio_irq_type;
748 else
749 gpio_irqchip.irq_set_type = gpio_irq_type;
750
751 for (pioc = 0, this = gpio_chip, prev = NULL;
752 pioc++ < gpio_banks;
753 prev = this, this++) {
754 int offset;
755
756 __raw_writel(~0, this->regbase + PIO_IDR);
757
758 /* setup irq domain for this GPIO controller */
759 at91_gpio_irqdomain(this);
760
761 for (offset = 0; offset < this->chip.ngpio; offset++) {
762 unsigned int virq = irq_find_mapping(this->domain, offset);
763 irq_set_lockdep_class(virq, &gpio_lock_class);
764
765 /*
766 * Can use the "simple" and not "edge" handler since it's
767 * shorter, and the AIC handles interrupts sanely.
768 */
769 irq_set_chip_and_handler(virq, &gpio_irqchip,
770 handle_simple_irq);
771 set_irq_flags(virq, IRQF_VALID);
772 irq_set_chip_data(virq, this);
773
774 gpio_irqnbr++;
775 }
776
777 /* The toplevel handler handles one bank of GPIOs, except
778 * on some SoC it can handles up to three...
779 * We only set up the handler for the first of the list.
780 */
781 if (prev && prev->next == this)
782 continue;
783
784 this->pioc_virq = irq_create_mapping(NULL, this->pioc_hwirq);
785 irq_set_chip_data(this->pioc_virq, this);
786 irq_set_chained_handler(this->pioc_virq, gpio_irq_handler);
787 }
788 pr_info("AT91: %d gpio irqs in %d banks\n", gpio_irqnbr, gpio_banks);
789}
790
791/* gpiolib support */
792static int at91_gpiolib_request(struct gpio_chip *chip, unsigned offset)
793{
794 struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
795 void __iomem *pio = at91_gpio->regbase;
796 unsigned mask = 1 << offset;
797
798 __raw_writel(mask, pio + PIO_PER);
799 return 0;
800}
801
802static int at91_gpiolib_direction_input(struct gpio_chip *chip,
803 unsigned offset)
804{
805 struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
806 void __iomem *pio = at91_gpio->regbase;
807 unsigned mask = 1 << offset;
808
809 __raw_writel(mask, pio + PIO_ODR);
810 return 0;
811}
812
813static int at91_gpiolib_direction_output(struct gpio_chip *chip,
814 unsigned offset, int val)
815{
816 struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
817 void __iomem *pio = at91_gpio->regbase;
818 unsigned mask = 1 << offset;
819
820 __raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
821 __raw_writel(mask, pio + PIO_OER);
822 return 0;
823}
824
825static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset)
826{
827 struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
828 void __iomem *pio = at91_gpio->regbase;
829 unsigned mask = 1 << offset;
830 u32 pdsr;
831
832 pdsr = __raw_readl(pio + PIO_PDSR);
833 return (pdsr & mask) != 0;
834}
835
836static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val)
837{
838 struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
839 void __iomem *pio = at91_gpio->regbase;
840 unsigned mask = 1 << offset;
841
842 __raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
843}
844
845static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
846{
847 int i;
848
849 for (i = 0; i < chip->ngpio; i++) {
850 unsigned pin = chip->base + i;
851 void __iomem *pio = pin_to_controller(pin);
852 unsigned mask = pin_to_mask(pin);
853 const char *gpio_label;
854
855 gpio_label = gpiochip_is_requested(chip, i);
856 if (gpio_label) {
857 seq_printf(s, "[%s] GPIO%s%d: ",
858 gpio_label, chip->label, i);
859 if (__raw_readl(pio + PIO_PSR) & mask)
860 seq_printf(s, "[gpio] %s\n",
861 at91_get_gpio_value(pin) ?
862 "set" : "clear");
863 else
864 seq_printf(s, "[periph %c]\n",
865 peripheral_function(pio, mask));
866 }
867 }
868}
869
870static int at91_gpiolib_to_irq(struct gpio_chip *chip, unsigned offset)
871{
872 struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
873 int virq;
874
875 if (offset < chip->ngpio)
876 virq = irq_create_mapping(at91_gpio->domain, offset);
877 else
878 virq = -ENXIO;
879
880 dev_dbg(chip->dev, "%s: request IRQ for GPIO %d, return %d\n",
881 chip->label, offset + chip->base, virq);
882 return virq;
883}
884
885static int __init at91_gpio_setup_clk(int idx)
886{
887 struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
888
889 /* retreive PIO controller's clock */
890 at91_gpio->clock = clk_get_sys(NULL, at91_gpio->chip.label);
891 if (IS_ERR(at91_gpio->clock)) {
892 pr_err("at91_gpio.%d, failed to get clock, ignoring.\n", idx);
893 goto err;
894 }
895
896 if (clk_prepare(at91_gpio->clock))
897 goto clk_prep_err;
898
899 /* enable PIO controller's clock */
900 if (clk_enable(at91_gpio->clock)) {
901 pr_err("at91_gpio.%d, failed to enable clock, ignoring.\n", idx);
902 goto clk_err;
903 }
904
905 return 0;
906
907clk_err:
908 clk_unprepare(at91_gpio->clock);
909clk_prep_err:
910 clk_put(at91_gpio->clock);
911err:
912 return -EINVAL;
913}
914
915static void __init at91_gpio_init_one(int idx, u32 regbase, int pioc_hwirq)
916{
917 struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
918
919 at91_gpio->chip.base = idx * MAX_NB_GPIO_PER_BANK;
920 at91_gpio->pioc_hwirq = pioc_hwirq;
921 at91_gpio->pioc_idx = idx;
922
923 at91_gpio->regbase = ioremap(regbase, 512);
924 if (!at91_gpio->regbase) {
925 pr_err("at91_gpio.%d, failed to map registers, ignoring.\n", idx);
926 return;
927 }
928
929 if (at91_gpio_setup_clk(idx))
930 goto ioremap_err;
931
932 gpio_banks = max(gpio_banks, idx + 1);
933 return;
934
935ioremap_err:
936 iounmap(at91_gpio->regbase);
937}
938
939/*
940 * Called from the processor-specific init to enable GPIO pin support.
941 */
942void __init at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
943{
944 unsigned i;
945 struct at91_gpio_chip *at91_gpio, *last = NULL;
946
947 BUG_ON(nr_banks > MAX_GPIO_BANKS);
948
949 if (of_have_populated_dt())
950 return;
951
952 for (i = 0; i < nr_banks; i++)
953 at91_gpio_init_one(i, data[i].regbase, data[i].id);
954
955 for (i = 0; i < gpio_banks; i++) {
956 at91_gpio = &gpio_chip[i];
957
958 /*
959 * GPIO controller are grouped on some SoC:
960 * PIOC, PIOD and PIOE can share the same IRQ line
961 */
962 if (last && last->pioc_hwirq == at91_gpio->pioc_hwirq)
963 last->next = at91_gpio;
964 last = at91_gpio;
965
966 gpiochip_add(&at91_gpio->chip);
967 }
968}