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Linux/arch/arm/mach-at91/gpio.c

  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/of_address.h>
 26 
 27 #include <asm/mach/irq.h>
 28 
 29 #include <mach/hardware.h>
 30 #include <mach/at91_pio.h>
 31 
 32 #include "generic.h"
 33 
 34 #define MAX_NB_GPIO_PER_BANK    32
 35 
 36 struct at91_gpio_chip {
 37         struct gpio_chip        chip;
 38         struct at91_gpio_chip   *next;          /* Bank sharing same clock */
 39         int                     pioc_hwirq;     /* PIO bank interrupt identifier on AIC */
 40         int                     pioc_virq;      /* PIO bank Linux virtual interrupt */
 41         int                     pioc_idx;       /* PIO bank index */
 42         void __iomem            *regbase;       /* PIO bank virtual address */
 43         struct clk              *clock;         /* associated clock */
 44         struct irq_domain       *domain;        /* associated irq domain */
 45 };
 46 
 47 #define to_at91_gpio_chip(c) container_of(c, struct at91_gpio_chip, chip)
 48 
 49 static int at91_gpiolib_request(struct gpio_chip *chip, unsigned offset);
 50 static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip);
 51 static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val);
 52 static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset);
 53 static int at91_gpiolib_direction_output(struct gpio_chip *chip,
 54                                          unsigned offset, int val);
 55 static int at91_gpiolib_direction_input(struct gpio_chip *chip,
 56                                         unsigned offset);
 57 static int at91_gpiolib_to_irq(struct gpio_chip *chip, unsigned offset);
 58 
 59 #define AT91_GPIO_CHIP(name)                                            \
 60         {                                                               \
 61                 .chip = {                                               \
 62                         .label            = name,                       \
 63                         .request          = at91_gpiolib_request,       \
 64                         .direction_input  = at91_gpiolib_direction_input, \
 65                         .direction_output = at91_gpiolib_direction_output, \
 66                         .get              = at91_gpiolib_get,           \
 67                         .set              = at91_gpiolib_set,           \
 68                         .dbg_show         = at91_gpiolib_dbg_show,      \
 69                         .to_irq           = at91_gpiolib_to_irq,        \
 70                         .ngpio            = MAX_NB_GPIO_PER_BANK,       \
 71                 },                                                      \
 72         }
 73 
 74 static struct at91_gpio_chip gpio_chip[] = {
 75         AT91_GPIO_CHIP("pioA"),
 76         AT91_GPIO_CHIP("pioB"),
 77         AT91_GPIO_CHIP("pioC"),
 78         AT91_GPIO_CHIP("pioD"),
 79         AT91_GPIO_CHIP("pioE"),
 80 };
 81 
 82 static int gpio_banks;
 83 static unsigned long at91_gpio_caps;
 84 
 85 /* All PIO controllers support PIO3 features */
 86 #define AT91_GPIO_CAP_PIO3      (1 <<  0)
 87 
 88 #define has_pio3()      (at91_gpio_caps & AT91_GPIO_CAP_PIO3)
 89 
 90 /*--------------------------------------------------------------------------*/
 91 
 92 static inline void __iomem *pin_to_controller(unsigned pin)
 93 {
 94         pin /= MAX_NB_GPIO_PER_BANK;
 95         if (likely(pin < gpio_banks))
 96                 return gpio_chip[pin].regbase;
 97 
 98         return NULL;
 99 }
100 
101 static inline unsigned pin_to_mask(unsigned pin)
102 {
103         return 1 << (pin % MAX_NB_GPIO_PER_BANK);
104 }
105 
106 
107 static char peripheral_function(void __iomem *pio, unsigned mask)
108 {
109         char    ret = 'X';
110         u8      select;
111 
112         if (pio) {
113                 if (has_pio3()) {
114                         select = !!(__raw_readl(pio + PIO_ABCDSR1) & mask);
115                         select |= (!!(__raw_readl(pio + PIO_ABCDSR2) & mask) << 1);
116                         ret = 'A' + select;
117                 } else {
118                         ret = __raw_readl(pio + PIO_ABSR) & mask ?
119                                                         'B' : 'A';
120                 }
121         }
122 
123         return ret;
124 }
125 
126 /*--------------------------------------------------------------------------*/
127 
128 /* Not all hardware capabilities are exposed through these calls; they
129  * only encapsulate the most common features and modes.  (So if you
130  * want to change signals in groups, do it directly.)
131  *
132  * Bootloaders will usually handle some of the pin multiplexing setup.
133  * The intent is certainly that by the time Linux is fully booted, all
134  * pins should have been fully initialized.  These setup calls should
135  * only be used by board setup routines, or possibly in driver probe().
136  *
137  * For bootloaders doing all that setup, these calls could be inlined
138  * as NOPs so Linux won't duplicate any setup code
139  */
140 
141 
142 /*
143  * mux the pin to the "GPIO" peripheral role.
144  */
145 int __init_or_module at91_set_GPIO_periph(unsigned pin, int use_pullup)
146 {
147         void __iomem    *pio = pin_to_controller(pin);
148         unsigned        mask = pin_to_mask(pin);
149 
150         if (!pio)
151                 return -EINVAL;
152         __raw_writel(mask, pio + PIO_IDR);
153         __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
154         __raw_writel(mask, pio + PIO_PER);
155         return 0;
156 }
157 EXPORT_SYMBOL(at91_set_GPIO_periph);
158 
159 
160 /*
161  * mux the pin to the "A" internal peripheral role.
162  */
163 int __init_or_module at91_set_A_periph(unsigned pin, int use_pullup)
164 {
165         void __iomem    *pio = pin_to_controller(pin);
166         unsigned        mask = pin_to_mask(pin);
167 
168         if (!pio)
169                 return -EINVAL;
170 
171         __raw_writel(mask, pio + PIO_IDR);
172         __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
173         if (has_pio3()) {
174                 __raw_writel(__raw_readl(pio + PIO_ABCDSR1) & ~mask,
175                                                         pio + PIO_ABCDSR1);
176                 __raw_writel(__raw_readl(pio + PIO_ABCDSR2) & ~mask,
177                                                         pio + PIO_ABCDSR2);
178         } else {
179                 __raw_writel(mask, pio + PIO_ASR);
180         }
181         __raw_writel(mask, pio + PIO_PDR);
182         return 0;
183 }
184 EXPORT_SYMBOL(at91_set_A_periph);
185 
186 
187 /*
188  * mux the pin to the "B" internal peripheral role.
189  */
190 int __init_or_module at91_set_B_periph(unsigned pin, int use_pullup)
191 {
192         void __iomem    *pio = pin_to_controller(pin);
193         unsigned        mask = pin_to_mask(pin);
194 
195         if (!pio)
196                 return -EINVAL;
197 
198         __raw_writel(mask, pio + PIO_IDR);
199         __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
200         if (has_pio3()) {
201                 __raw_writel(__raw_readl(pio + PIO_ABCDSR1) | mask,
202                                                         pio + PIO_ABCDSR1);
203                 __raw_writel(__raw_readl(pio + PIO_ABCDSR2) & ~mask,
204                                                         pio + PIO_ABCDSR2);
205         } else {
206                 __raw_writel(mask, pio + PIO_BSR);
207         }
208         __raw_writel(mask, pio + PIO_PDR);
209         return 0;
210 }
211 EXPORT_SYMBOL(at91_set_B_periph);
212 
213 
214 /*
215  * mux the pin to the "C" internal peripheral role.
216  */
217 int __init_or_module at91_set_C_periph(unsigned pin, int use_pullup)
218 {
219         void __iomem    *pio = pin_to_controller(pin);
220         unsigned        mask = pin_to_mask(pin);
221 
222         if (!pio || !has_pio3())
223                 return -EINVAL;
224 
225         __raw_writel(mask, pio + PIO_IDR);
226         __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
227         __raw_writel(__raw_readl(pio + PIO_ABCDSR1) & ~mask, pio + PIO_ABCDSR1);
228         __raw_writel(__raw_readl(pio + PIO_ABCDSR2) | mask, pio + PIO_ABCDSR2);
229         __raw_writel(mask, pio + PIO_PDR);
230         return 0;
231 }
232 EXPORT_SYMBOL(at91_set_C_periph);
233 
234 
235 /*
236  * mux the pin to the "D" internal peripheral role.
237  */
238 int __init_or_module at91_set_D_periph(unsigned pin, int use_pullup)
239 {
240         void __iomem    *pio = pin_to_controller(pin);
241         unsigned        mask = pin_to_mask(pin);
242 
243         if (!pio || !has_pio3())
244                 return -EINVAL;
245 
246         __raw_writel(mask, pio + PIO_IDR);
247         __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
248         __raw_writel(__raw_readl(pio + PIO_ABCDSR1) | mask, pio + PIO_ABCDSR1);
249         __raw_writel(__raw_readl(pio + PIO_ABCDSR2) | mask, pio + PIO_ABCDSR2);
250         __raw_writel(mask, pio + PIO_PDR);
251         return 0;
252 }
253 EXPORT_SYMBOL(at91_set_D_periph);
254 
255 
256 /*
257  * mux the pin to the gpio controller (instead of "A", "B", "C"
258  * or "D" peripheral), and configure it for an input.
259  */
260 int __init_or_module at91_set_gpio_input(unsigned pin, int use_pullup)
261 {
262         void __iomem    *pio = pin_to_controller(pin);
263         unsigned        mask = pin_to_mask(pin);
264 
265         if (!pio)
266                 return -EINVAL;
267 
268         __raw_writel(mask, pio + PIO_IDR);
269         __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
270         __raw_writel(mask, pio + PIO_ODR);
271         __raw_writel(mask, pio + PIO_PER);
272         return 0;
273 }
274 EXPORT_SYMBOL(at91_set_gpio_input);
275 
276 
277 /*
278  * mux the pin to the gpio controller (instead of "A", "B", "C"
279  * or "D" peripheral), and configure it for an output.
280  */
281 int __init_or_module at91_set_gpio_output(unsigned pin, int value)
282 {
283         void __iomem    *pio = pin_to_controller(pin);
284         unsigned        mask = pin_to_mask(pin);
285 
286         if (!pio)
287                 return -EINVAL;
288 
289         __raw_writel(mask, pio + PIO_IDR);
290         __raw_writel(mask, pio + PIO_PUDR);
291         __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
292         __raw_writel(mask, pio + PIO_OER);
293         __raw_writel(mask, pio + PIO_PER);
294         return 0;
295 }
296 EXPORT_SYMBOL(at91_set_gpio_output);
297 
298 
299 /*
300  * enable/disable the glitch filter; mostly used with IRQ handling.
301  */
302 int __init_or_module at91_set_deglitch(unsigned pin, int is_on)
303 {
304         void __iomem    *pio = pin_to_controller(pin);
305         unsigned        mask = pin_to_mask(pin);
306 
307         if (!pio)
308                 return -EINVAL;
309 
310         if (has_pio3() && is_on)
311                 __raw_writel(mask, pio + PIO_IFSCDR);
312         __raw_writel(mask, pio + (is_on ? PIO_IFER : PIO_IFDR));
313         return 0;
314 }
315 EXPORT_SYMBOL(at91_set_deglitch);
316 
317 /*
318  * enable/disable the debounce filter;
319  */
320 int __init_or_module at91_set_debounce(unsigned pin, int is_on, int div)
321 {
322         void __iomem    *pio = pin_to_controller(pin);
323         unsigned        mask = pin_to_mask(pin);
324 
325         if (!pio || !has_pio3())
326                 return -EINVAL;
327 
328         if (is_on) {
329                 __raw_writel(mask, pio + PIO_IFSCER);
330                 __raw_writel(div & PIO_SCDR_DIV, pio + PIO_SCDR);
331                 __raw_writel(mask, pio + PIO_IFER);
332         } else {
333                 __raw_writel(mask, pio + PIO_IFDR);
334         }
335         return 0;
336 }
337 EXPORT_SYMBOL(at91_set_debounce);
338 
339 /*
340  * enable/disable the multi-driver; This is only valid for output and
341  * allows the output pin to run as an open collector output.
342  */
343 int __init_or_module at91_set_multi_drive(unsigned pin, int is_on)
344 {
345         void __iomem    *pio = pin_to_controller(pin);
346         unsigned        mask = pin_to_mask(pin);
347 
348         if (!pio)
349                 return -EINVAL;
350 
351         __raw_writel(mask, pio + (is_on ? PIO_MDER : PIO_MDDR));
352         return 0;
353 }
354 EXPORT_SYMBOL(at91_set_multi_drive);
355 
356 /*
357  * enable/disable the pull-down.
358  * If pull-up already enabled while calling the function, we disable it.
359  */
360 int __init_or_module at91_set_pulldown(unsigned pin, int is_on)
361 {
362         void __iomem    *pio = pin_to_controller(pin);
363         unsigned        mask = pin_to_mask(pin);
364 
365         if (!pio || !has_pio3())
366                 return -EINVAL;
367 
368         /* Disable pull-up anyway */
369         __raw_writel(mask, pio + PIO_PUDR);
370         __raw_writel(mask, pio + (is_on ? PIO_PPDER : PIO_PPDDR));
371         return 0;
372 }
373 EXPORT_SYMBOL(at91_set_pulldown);
374 
375 /*
376  * disable Schmitt trigger
377  */
378 int __init_or_module at91_disable_schmitt_trig(unsigned pin)
379 {
380         void __iomem    *pio = pin_to_controller(pin);
381         unsigned        mask = pin_to_mask(pin);
382 
383         if (!pio || !has_pio3())
384                 return -EINVAL;
385 
386         __raw_writel(__raw_readl(pio + PIO_SCHMITT) | mask, pio + PIO_SCHMITT);
387         return 0;
388 }
389 EXPORT_SYMBOL(at91_disable_schmitt_trig);
390 
391 /*
392  * assuming the pin is muxed as a gpio output, set its value.
393  */
394 int at91_set_gpio_value(unsigned pin, int value)
395 {
396         void __iomem    *pio = pin_to_controller(pin);
397         unsigned        mask = pin_to_mask(pin);
398 
399         if (!pio)
400                 return -EINVAL;
401         __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
402         return 0;
403 }
404 EXPORT_SYMBOL(at91_set_gpio_value);
405 
406 
407 /*
408  * read the pin's value (works even if it's not muxed as a gpio).
409  */
410 int at91_get_gpio_value(unsigned pin)
411 {
412         void __iomem    *pio = pin_to_controller(pin);
413         unsigned        mask = pin_to_mask(pin);
414         u32             pdsr;
415 
416         if (!pio)
417                 return -EINVAL;
418         pdsr = __raw_readl(pio + PIO_PDSR);
419         return (pdsr & mask) != 0;
420 }
421 EXPORT_SYMBOL(at91_get_gpio_value);
422 
423 /*--------------------------------------------------------------------------*/
424 
425 #ifdef CONFIG_PM
426 
427 static u32 wakeups[MAX_GPIO_BANKS];
428 static u32 backups[MAX_GPIO_BANKS];
429 
430 static int gpio_irq_set_wake(struct irq_data *d, unsigned state)
431 {
432         struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
433         unsigned        mask = 1 << d->hwirq;
434         unsigned        bank = at91_gpio->pioc_idx;
435 
436         if (unlikely(bank >= MAX_GPIO_BANKS))
437                 return -EINVAL;
438 
439         if (state)
440                 wakeups[bank] |= mask;
441         else
442                 wakeups[bank] &= ~mask;
443 
444         irq_set_irq_wake(at91_gpio->pioc_virq, state);
445 
446         return 0;
447 }
448 
449 void at91_gpio_suspend(void)
450 {
451         int i;
452 
453         for (i = 0; i < gpio_banks; i++) {
454                 void __iomem    *pio = gpio_chip[i].regbase;
455 
456                 backups[i] = __raw_readl(pio + PIO_IMR);
457                 __raw_writel(backups[i], pio + PIO_IDR);
458                 __raw_writel(wakeups[i], pio + PIO_IER);
459 
460                 if (!wakeups[i]) {
461                         clk_unprepare(gpio_chip[i].clock);
462                         clk_disable(gpio_chip[i].clock);
463                 } else {
464 #ifdef CONFIG_PM_DEBUG
465                         printk(KERN_DEBUG "GPIO-%c may wake for %08x\n", 'A'+i, wakeups[i]);
466 #endif
467                 }
468         }
469 }
470 
471 void at91_gpio_resume(void)
472 {
473         int i;
474 
475         for (i = 0; i < gpio_banks; i++) {
476                 void __iomem    *pio = gpio_chip[i].regbase;
477 
478                 if (!wakeups[i]) {
479                         if (clk_prepare(gpio_chip[i].clock) == 0)
480                                 clk_enable(gpio_chip[i].clock);
481                 }
482 
483                 __raw_writel(wakeups[i], pio + PIO_IDR);
484                 __raw_writel(backups[i], pio + PIO_IER);
485         }
486 }
487 
488 #else
489 #define gpio_irq_set_wake       NULL
490 #endif
491 
492 
493 /* Several AIC controller irqs are dispatched through this GPIO handler.
494  * To use any AT91_PIN_* as an externally triggered IRQ, first call
495  * at91_set_gpio_input() then maybe enable its glitch filter.
496  * Then just request_irq() with the pin ID; it works like any ARM IRQ
497  * handler.
498  * First implementation always triggers on rising and falling edges
499  * whereas the newer PIO3 can be additionally configured to trigger on
500  * level, edge with any polarity.
501  *
502  * Alternatively, certain pins may be used directly as IRQ0..IRQ6 after
503  * configuring them with at91_set_a_periph() or at91_set_b_periph().
504  * IRQ0..IRQ6 should be configurable, e.g. level vs edge triggering.
505  */
506 
507 static void gpio_irq_mask(struct irq_data *d)
508 {
509         struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
510         void __iomem    *pio = at91_gpio->regbase;
511         unsigned        mask = 1 << d->hwirq;
512 
513         if (pio)
514                 __raw_writel(mask, pio + PIO_IDR);
515 }
516 
517 static void gpio_irq_unmask(struct irq_data *d)
518 {
519         struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
520         void __iomem    *pio = at91_gpio->regbase;
521         unsigned        mask = 1 << d->hwirq;
522 
523         if (pio)
524                 __raw_writel(mask, pio + PIO_IER);
525 }
526 
527 static int gpio_irq_type(struct irq_data *d, unsigned type)
528 {
529         switch (type) {
530         case IRQ_TYPE_NONE:
531         case IRQ_TYPE_EDGE_BOTH:
532                 return 0;
533         default:
534                 return -EINVAL;
535         }
536 }
537 
538 /* Alternate irq type for PIO3 support */
539 static int alt_gpio_irq_type(struct irq_data *d, unsigned type)
540 {
541         struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
542         void __iomem    *pio = at91_gpio->regbase;
543         unsigned        mask = 1 << d->hwirq;
544 
545         switch (type) {
546         case IRQ_TYPE_EDGE_RISING:
547                 __raw_writel(mask, pio + PIO_ESR);
548                 __raw_writel(mask, pio + PIO_REHLSR);
549                 break;
550         case IRQ_TYPE_EDGE_FALLING:
551                 __raw_writel(mask, pio + PIO_ESR);
552                 __raw_writel(mask, pio + PIO_FELLSR);
553                 break;
554         case IRQ_TYPE_LEVEL_LOW:
555                 __raw_writel(mask, pio + PIO_LSR);
556                 __raw_writel(mask, pio + PIO_FELLSR);
557                 break;
558         case IRQ_TYPE_LEVEL_HIGH:
559                 __raw_writel(mask, pio + PIO_LSR);
560                 __raw_writel(mask, pio + PIO_REHLSR);
561                 break;
562         case IRQ_TYPE_EDGE_BOTH:
563                 /*
564                  * disable additional interrupt modes:
565                  * fall back to default behavior
566                  */
567                 __raw_writel(mask, pio + PIO_AIMDR);
568                 return 0;
569         case IRQ_TYPE_NONE:
570         default:
571                 pr_warn("AT91: No type for irq %d\n", gpio_to_irq(d->irq));
572                 return -EINVAL;
573         }
574 
575         /* enable additional interrupt modes */
576         __raw_writel(mask, pio + PIO_AIMER);
577 
578         return 0;
579 }
580 
581 static struct irq_chip gpio_irqchip = {
582         .name           = "GPIO",
583         .irq_disable    = gpio_irq_mask,
584         .irq_mask       = gpio_irq_mask,
585         .irq_unmask     = gpio_irq_unmask,
586         /* .irq_set_type is set dynamically */
587         .irq_set_wake   = gpio_irq_set_wake,
588 };
589 
590 static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
591 {
592         struct irq_chip *chip = irq_desc_get_chip(desc);
593         struct irq_data *idata = irq_desc_get_irq_data(desc);
594         struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(idata);
595         void __iomem    *pio = at91_gpio->regbase;
596         unsigned long   isr;
597         int             n;
598 
599         chained_irq_enter(chip, desc);
600         for (;;) {
601                 /* Reading ISR acks pending (edge triggered) GPIO interrupts.
602                  * When there none are pending, we're finished unless we need
603                  * to process multiple banks (like ID_PIOCDE on sam9263).
604                  */
605                 isr = __raw_readl(pio + PIO_ISR) & __raw_readl(pio + PIO_IMR);
606                 if (!isr) {
607                         if (!at91_gpio->next)
608                                 break;
609                         at91_gpio = at91_gpio->next;
610                         pio = at91_gpio->regbase;
611                         continue;
612                 }
613 
614                 n = find_first_bit(&isr, BITS_PER_LONG);
615                 while (n < BITS_PER_LONG) {
616                         generic_handle_irq(irq_find_mapping(at91_gpio->domain, n));
617                         n = find_next_bit(&isr, BITS_PER_LONG, n + 1);
618                 }
619         }
620         chained_irq_exit(chip, desc);
621         /* now it may re-trigger */
622 }
623 
624 /*--------------------------------------------------------------------------*/
625 
626 #ifdef CONFIG_DEBUG_FS
627 
628 static void gpio_printf(struct seq_file *s, void __iomem *pio, unsigned mask)
629 {
630         char    *trigger = NULL;
631         char    *polarity = NULL;
632 
633         if (__raw_readl(pio + PIO_IMR) & mask) {
634                 if (!has_pio3() || !(__raw_readl(pio + PIO_AIMMR) & mask )) {
635                         trigger = "edge";
636                         polarity = "both";
637                 } else {
638                         if (__raw_readl(pio + PIO_ELSR) & mask) {
639                                 trigger = "level";
640                                 polarity = __raw_readl(pio + PIO_FRLHSR) & mask ?
641                                         "high" : "low";
642                         } else {
643                                 trigger = "edge";
644                                 polarity = __raw_readl(pio + PIO_FRLHSR) & mask ?
645                                                 "rising" : "falling";
646                         }
647                 }
648                 seq_printf(s, "IRQ:%s-%s\t", trigger, polarity);
649         } else {
650                 seq_printf(s, "GPIO:%s\t\t",
651                                 __raw_readl(pio + PIO_PDSR) & mask ? "1" : "");
652         }
653 }
654 
655 static int at91_gpio_show(struct seq_file *s, void *unused)
656 {
657         int bank, j;
658 
659         /* print heading */
660         seq_printf(s, "Pin\t");
661         for (bank = 0; bank < gpio_banks; bank++) {
662                 seq_printf(s, "PIO%c\t\t", 'A' + bank);
663         };
664         seq_printf(s, "\n\n");
665 
666         /* print pin status */
667         for (j = 0; j < 32; j++) {
668                 seq_printf(s, "%i:\t", j);
669 
670                 for (bank = 0; bank < gpio_banks; bank++) {
671                         unsigned        pin  = (32 * bank) + j;
672                         void __iomem    *pio = pin_to_controller(pin);
673                         unsigned        mask = pin_to_mask(pin);
674 
675                         if (__raw_readl(pio + PIO_PSR) & mask)
676                                 gpio_printf(s, pio, mask);
677                         else
678                                 seq_printf(s, "%c\t\t",
679                                                 peripheral_function(pio, mask));
680                 }
681 
682                 seq_printf(s, "\n");
683         }
684 
685         return 0;
686 }
687 
688 static int at91_gpio_open(struct inode *inode, struct file *file)
689 {
690         return single_open(file, at91_gpio_show, NULL);
691 }
692 
693 static const struct file_operations at91_gpio_operations = {
694         .open           = at91_gpio_open,
695         .read           = seq_read,
696         .llseek         = seq_lseek,
697         .release        = single_release,
698 };
699 
700 static int __init at91_gpio_debugfs_init(void)
701 {
702         /* /sys/kernel/debug/at91_gpio */
703         (void) debugfs_create_file("at91_gpio", S_IFREG | S_IRUGO, NULL, NULL, &at91_gpio_operations);
704         return 0;
705 }
706 postcore_initcall(at91_gpio_debugfs_init);
707 
708 #endif
709 
710 /*--------------------------------------------------------------------------*/
711 
712 /*
713  * This lock class tells lockdep that GPIO irqs are in a different
714  * category than their parents, so it won't report false recursion.
715  */
716 static struct lock_class_key gpio_lock_class;
717 
718 /*
719  * irqdomain initialization: pile up irqdomains on top of AIC range
720  */
721 static void __init at91_gpio_irqdomain(struct at91_gpio_chip *at91_gpio)
722 {
723         int irq_base;
724 
725         irq_base = irq_alloc_descs(-1, 0, at91_gpio->chip.ngpio, 0);
726         if (irq_base < 0)
727                 panic("at91_gpio.%d: error %d: couldn't allocate IRQ numbers.\n",
728                         at91_gpio->pioc_idx, irq_base);
729         at91_gpio->domain = irq_domain_add_legacy(NULL, at91_gpio->chip.ngpio,
730                                                   irq_base, 0,
731                                                   &irq_domain_simple_ops, NULL);
732         if (!at91_gpio->domain)
733                 panic("at91_gpio.%d: couldn't allocate irq domain.\n",
734                         at91_gpio->pioc_idx);
735 }
736 
737 /*
738  * Called from the processor-specific init to enable GPIO interrupt support.
739  */
740 void __init at91_gpio_irq_setup(void)
741 {
742         unsigned                pioc;
743         int                     gpio_irqnbr = 0;
744         struct at91_gpio_chip   *this, *prev;
745 
746         /* Setup proper .irq_set_type function */
747         if (has_pio3())
748                 gpio_irqchip.irq_set_type = alt_gpio_irq_type;
749         else
750                 gpio_irqchip.irq_set_type = gpio_irq_type;
751 
752         for (pioc = 0, this = gpio_chip, prev = NULL;
753                         pioc++ < gpio_banks;
754                         prev = this, this++) {
755                 int offset;
756 
757                 __raw_writel(~0, this->regbase + PIO_IDR);
758 
759                 /* setup irq domain for this GPIO controller */
760                 at91_gpio_irqdomain(this);
761 
762                 for (offset = 0; offset < this->chip.ngpio; offset++) {
763                         unsigned int virq = irq_find_mapping(this->domain, offset);
764                         irq_set_lockdep_class(virq, &gpio_lock_class);
765 
766                         /*
767                          * Can use the "simple" and not "edge" handler since it's
768                          * shorter, and the AIC handles interrupts sanely.
769                          */
770                         irq_set_chip_and_handler(virq, &gpio_irqchip,
771                                                  handle_simple_irq);
772                         set_irq_flags(virq, IRQF_VALID);
773                         irq_set_chip_data(virq, this);
774 
775                         gpio_irqnbr++;
776                 }
777 
778                 /* The toplevel handler handles one bank of GPIOs, except
779                  * on some SoC it can handles up to three...
780                  * We only set up the handler for the first of the list.
781                  */
782                 if (prev && prev->next == this)
783                         continue;
784 
785                 this->pioc_virq = irq_create_mapping(NULL, this->pioc_hwirq);
786                 irq_set_chip_data(this->pioc_virq, this);
787                 irq_set_chained_handler(this->pioc_virq, gpio_irq_handler);
788         }
789         pr_info("AT91: %d gpio irqs in %d banks\n", gpio_irqnbr, gpio_banks);
790 }
791 
792 /* gpiolib support */
793 static int at91_gpiolib_request(struct gpio_chip *chip, unsigned offset)
794 {
795         struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
796         void __iomem *pio = at91_gpio->regbase;
797         unsigned mask = 1 << offset;
798 
799         __raw_writel(mask, pio + PIO_PER);
800         return 0;
801 }
802 
803 static int at91_gpiolib_direction_input(struct gpio_chip *chip,
804                                         unsigned offset)
805 {
806         struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
807         void __iomem *pio = at91_gpio->regbase;
808         unsigned mask = 1 << offset;
809 
810         __raw_writel(mask, pio + PIO_ODR);
811         return 0;
812 }
813 
814 static int at91_gpiolib_direction_output(struct gpio_chip *chip,
815                                          unsigned offset, int val)
816 {
817         struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
818         void __iomem *pio = at91_gpio->regbase;
819         unsigned mask = 1 << offset;
820 
821         __raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
822         __raw_writel(mask, pio + PIO_OER);
823         return 0;
824 }
825 
826 static int at91_gpiolib_get(struct gpio_chip *chip, unsigned offset)
827 {
828         struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
829         void __iomem *pio = at91_gpio->regbase;
830         unsigned mask = 1 << offset;
831         u32 pdsr;
832 
833         pdsr = __raw_readl(pio + PIO_PDSR);
834         return (pdsr & mask) != 0;
835 }
836 
837 static void at91_gpiolib_set(struct gpio_chip *chip, unsigned offset, int val)
838 {
839         struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
840         void __iomem *pio = at91_gpio->regbase;
841         unsigned mask = 1 << offset;
842 
843         __raw_writel(mask, pio + (val ? PIO_SODR : PIO_CODR));
844 }
845 
846 static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
847 {
848         int i;
849 
850         for (i = 0; i < chip->ngpio; i++) {
851                 unsigned pin = chip->base + i;
852                 void __iomem *pio = pin_to_controller(pin);
853                 unsigned mask = pin_to_mask(pin);
854                 const char *gpio_label;
855 
856                 gpio_label = gpiochip_is_requested(chip, i);
857                 if (gpio_label) {
858                         seq_printf(s, "[%s] GPIO%s%d: ",
859                                    gpio_label, chip->label, i);
860                         if (__raw_readl(pio + PIO_PSR) & mask)
861                                 seq_printf(s, "[gpio] %s\n",
862                                            at91_get_gpio_value(pin) ?
863                                            "set" : "clear");
864                         else
865                                 seq_printf(s, "[periph %c]\n",
866                                            peripheral_function(pio, mask));
867                 }
868         }
869 }
870 
871 static int at91_gpiolib_to_irq(struct gpio_chip *chip, unsigned offset)
872 {
873         struct at91_gpio_chip *at91_gpio = to_at91_gpio_chip(chip);
874         int virq;
875 
876         if (offset < chip->ngpio)
877                 virq = irq_create_mapping(at91_gpio->domain, offset);
878         else
879                 virq = -ENXIO;
880 
881         dev_dbg(chip->dev, "%s: request IRQ for GPIO %d, return %d\n",
882                                 chip->label, offset + chip->base, virq);
883         return virq;
884 }
885 
886 static int __init at91_gpio_setup_clk(int idx)
887 {
888         struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
889 
890         /* retreive PIO controller's clock */
891         at91_gpio->clock = clk_get_sys(NULL, at91_gpio->chip.label);
892         if (IS_ERR(at91_gpio->clock)) {
893                 pr_err("at91_gpio.%d, failed to get clock, ignoring.\n", idx);
894                 goto err;
895         }
896 
897         if (clk_prepare(at91_gpio->clock))
898                 goto clk_prep_err;
899 
900         /* enable PIO controller's clock */
901         if (clk_enable(at91_gpio->clock)) {
902                 pr_err("at91_gpio.%d, failed to enable clock, ignoring.\n", idx);
903                 goto clk_err;
904         }
905 
906         return 0;
907 
908 clk_err:
909         clk_unprepare(at91_gpio->clock);
910 clk_prep_err:
911         clk_put(at91_gpio->clock);
912 err:
913         return -EINVAL;
914 }
915 
916 static void __init at91_gpio_init_one(int idx, u32 regbase, int pioc_hwirq)
917 {
918         struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
919 
920         at91_gpio->chip.base = idx * MAX_NB_GPIO_PER_BANK;
921         at91_gpio->pioc_hwirq = pioc_hwirq;
922         at91_gpio->pioc_idx = idx;
923 
924         at91_gpio->regbase = ioremap(regbase, 512);
925         if (!at91_gpio->regbase) {
926                 pr_err("at91_gpio.%d, failed to map registers, ignoring.\n", idx);
927                 return;
928         }
929 
930         if (at91_gpio_setup_clk(idx))
931                 goto ioremap_err;
932 
933         gpio_banks = max(gpio_banks, idx + 1);
934         return;
935 
936 ioremap_err:
937         iounmap(at91_gpio->regbase);
938 }
939 
940 /*
941  * Called from the processor-specific init to enable GPIO pin support.
942  */
943 void __init at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
944 {
945         unsigned i;
946         struct at91_gpio_chip *at91_gpio, *last = NULL;
947 
948         BUG_ON(nr_banks > MAX_GPIO_BANKS);
949 
950         if (of_have_populated_dt())
951                 return;
952 
953         for (i = 0; i < nr_banks; i++)
954                 at91_gpio_init_one(i, data[i].regbase, data[i].id);
955 
956         for (i = 0; i < gpio_banks; i++) {
957                 at91_gpio = &gpio_chip[i];
958 
959                 /*
960                  * GPIO controller are grouped on some SoC:
961                  * PIOC, PIOD and PIOE can share the same IRQ line
962                  */
963                 if (last && last->pioc_hwirq == at91_gpio->pioc_hwirq)
964                         last->next = at91_gpio;
965                 last = at91_gpio;
966 
967                 gpiochip_add(&at91_gpio->chip);
968         }
969 }
970 

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