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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 
35 struct 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 
48 static int at91_gpiolib_request(struct gpio_chip *chip, unsigned offset);
49 static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip);
50 static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val);
51 static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset);
52 static int at91_gpiolib_direction_output(struct gpio_chip *chip,
53 					 unsigned offset, int val);
54 static int at91_gpiolib_direction_input(struct gpio_chip *chip,
55 					unsigned offset);
56 static 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 
73 static 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 
81 static int gpio_banks;
82 static 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 
pin_to_controller(unsigned pin)91 static 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 
pin_to_mask(unsigned pin)100 static inline unsigned pin_to_mask(unsigned pin)
101 {
102 	return 1 << (pin % MAX_NB_GPIO_PER_BANK);
103 }
104 
105 
peripheral_function(void __iomem * pio,unsigned mask)106 static 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  */
at91_set_GPIO_periph(unsigned pin,int use_pullup)144 int __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 }
156 EXPORT_SYMBOL(at91_set_GPIO_periph);
157 
158 
159 /*
160  * mux the pin to the "A" internal peripheral role.
161  */
at91_set_A_periph(unsigned pin,int use_pullup)162 int __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 }
183 EXPORT_SYMBOL(at91_set_A_periph);
184 
185 
186 /*
187  * mux the pin to the "B" internal peripheral role.
188  */
at91_set_B_periph(unsigned pin,int use_pullup)189 int __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 }
210 EXPORT_SYMBOL(at91_set_B_periph);
211 
212 
213 /*
214  * mux the pin to the "C" internal peripheral role.
215  */
at91_set_C_periph(unsigned pin,int use_pullup)216 int __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 }
231 EXPORT_SYMBOL(at91_set_C_periph);
232 
233 
234 /*
235  * mux the pin to the "D" internal peripheral role.
236  */
at91_set_D_periph(unsigned pin,int use_pullup)237 int __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 }
252 EXPORT_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  */
at91_set_gpio_input(unsigned pin,int use_pullup)259 int __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 }
273 EXPORT_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  */
at91_set_gpio_output(unsigned pin,int value)280 int __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 }
295 EXPORT_SYMBOL(at91_set_gpio_output);
296 
297 
298 /*
299  * enable/disable the glitch filter; mostly used with IRQ handling.
300  */
at91_set_deglitch(unsigned pin,int is_on)301 int __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 }
314 EXPORT_SYMBOL(at91_set_deglitch);
315 
316 /*
317  * enable/disable the debounce filter;
318  */
at91_set_debounce(unsigned pin,int is_on,int div)319 int __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 }
336 EXPORT_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  */
at91_set_multi_drive(unsigned pin,int is_on)342 int __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 }
353 EXPORT_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  */
at91_set_pulldown(unsigned pin,int is_on)359 int __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 }
372 EXPORT_SYMBOL(at91_set_pulldown);
373 
374 /*
375  * disable Schmitt trigger
376  */
at91_disable_schmitt_trig(unsigned pin)377 int __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 }
388 EXPORT_SYMBOL(at91_disable_schmitt_trig);
389 
390 /*
391  * assuming the pin is muxed as a gpio output, set its value.
392  */
at91_set_gpio_value(unsigned pin,int value)393 int 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 }
403 EXPORT_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  */
at91_get_gpio_value(unsigned pin)409 int 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 }
420 EXPORT_SYMBOL(at91_get_gpio_value);
421 
422 /*--------------------------------------------------------------------------*/
423 
424 #ifdef CONFIG_PM
425 
426 static u32 wakeups[MAX_GPIO_BANKS];
427 static u32 backups[MAX_GPIO_BANKS];
428 
gpio_irq_set_wake(struct irq_data * d,unsigned state)429 static 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 
at91_gpio_suspend(void)448 void 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 
at91_gpio_resume(void)470 void 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 
gpio_irq_mask(struct irq_data * d)506 static 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 
gpio_irq_unmask(struct irq_data * d)516 static 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 
gpio_irq_type(struct irq_data * d,unsigned type)526 static 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 */
alt_gpio_irq_type(struct irq_data * d,unsigned type)538 static 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 
580 static 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 
gpio_irq_handler(unsigned irq,struct irq_desc * desc)589 static 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 
gpio_printf(struct seq_file * s,void __iomem * pio,unsigned mask)627 static 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 
at91_gpio_show(struct seq_file * s,void * unused)654 static 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 
at91_gpio_open(struct inode * inode,struct file * file)687 static int at91_gpio_open(struct inode *inode, struct file *file)
688 {
689 	return single_open(file, at91_gpio_show, NULL);
690 }
691 
692 static 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 
at91_gpio_debugfs_init(void)699 static 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 }
705 postcore_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  */
715 static struct lock_class_key gpio_lock_class;
716 
717 /*
718  * irqdomain initialization: pile up irqdomains on top of AIC range
719  */
at91_gpio_irqdomain(struct at91_gpio_chip * at91_gpio)720 static 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  */
at91_gpio_irq_setup(void)739 void __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 */
at91_gpiolib_request(struct gpio_chip * chip,unsigned offset)792 static 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 
at91_gpiolib_direction_input(struct gpio_chip * chip,unsigned offset)802 static 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 
at91_gpiolib_direction_output(struct gpio_chip * chip,unsigned offset,int val)813 static 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 
at91_gpiolib_get(struct gpio_chip * chip,unsigned offset)825 static 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 
at91_gpiolib_set(struct gpio_chip * chip,unsigned offset,int val)836 static 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 
at91_gpiolib_dbg_show(struct seq_file * s,struct gpio_chip * chip)845 static 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 
at91_gpiolib_to_irq(struct gpio_chip * chip,unsigned offset)870 static 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 
at91_gpio_setup_clk(int idx)885 static 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 
907 clk_err:
908 	clk_unprepare(at91_gpio->clock);
909 clk_prep_err:
910 	clk_put(at91_gpio->clock);
911 err:
912 	return -EINVAL;
913 }
914 
at91_gpio_init_one(int idx,u32 regbase,int pioc_hwirq)915 static 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 
935 ioremap_err:
936 	iounmap(at91_gpio->regbase);
937 }
938 
939 /*
940  * Called from the processor-specific init to enable GPIO pin support.
941  */
at91_gpio_init(struct at91_gpio_bank * data,int nr_banks)942 void __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 }
969