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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-02-19 16:18:39 -0500
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-02-19 16:18:39 -0500
commit59b8175c771040afcd4ad67022b0cc80c216b866 (patch)
tree4ef5935bee1e342716d49b9d4b99e3fa835526e6 /arch/arm/mach-at91/gpio.c
parent920841d8d1d61bc12b43f95a579a5374f6d98f81 (diff)
parent3b0eb4a195a124567cd0dd6f700f8388def542c6 (diff)
Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (117 commits) [ARM] 4058/2: iop32x: set ->broken_parity_status on n2100 onboard r8169 ports [ARM] 4140/1: AACI stability add ac97 timeout and retries [ARM] 4139/1: AACI record support [ARM] 4138/1: AACI: multiple channel support for IRQ handling [ARM] 4211/1: Provide a defconfig for ns9xxx [ARM] 4210/1: base for new machine type "NetSilicon NS9360" [ARM] 4222/1: S3C2443: Remove reference to missing S3C2443_PM [ARM] 4221/1: S3C2443: DMA support [ARM] 4220/1: S3C24XX: DMA system initialised from sysdev [ARM] 4219/1: S3C2443: DMA source definitions [ARM] 4218/1: S3C2412: fix CONFIG_CPU_S3C2412_ONLY wrt to S3C2443 [ARM] 4217/1: S3C24XX: remove the dma channel show at startup [ARM] 4090/2: avoid clash between PXA and SA1111 defines [ARM] 4216/1: add .gitignore entries for ARM specific files [ARM] 4214/2: S3C2410: Add Armzone QT2410 [ARM] 4215/1: s3c2410 usb device: per-platform vbus_draw [ARM] 4213/1: S3C2410 - Update definition of ADCTSC_XY_PST [ARM] 4098/1: ARM: rtc_lock only used with rtc_cmos [ARM] 4137/1: Add kexec support [ARM] 4201/1: SMP barriers pair needed for the secondary boot process ... Fix up conflict due to typedef removal in sound/arm/aaci.h
Diffstat (limited to 'arch/arm/mach-at91/gpio.c')
-rw-r--r--arch/arm/mach-at91/gpio.c462
1 files changed, 462 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/gpio.c b/arch/arm/mach-at91/gpio.c
new file mode 100644
index 000000000000..7b87f3f101b7
--- /dev/null
+++ b/arch/arm/mach-at91/gpio.c
@@ -0,0 +1,462 @@
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/interrupt.h>
15#include <linux/irq.h>
16#include <linux/kernel.h>
17#include <linux/list.h>
18#include <linux/module.h>
19
20#include <asm/io.h>
21#include <asm/hardware.h>
22#include <asm/arch/at91_pio.h>
23#include <asm/arch/gpio.h>
24
25#include "generic.h"
26
27
28static struct at91_gpio_bank *gpio;
29static int gpio_banks;
30
31
32static inline void __iomem *pin_to_controller(unsigned pin)
33{
34 void __iomem *sys_base = (void __iomem *) AT91_VA_BASE_SYS;
35
36 pin -= PIN_BASE;
37 pin /= 32;
38 if (likely(pin < gpio_banks))
39 return sys_base + gpio[pin].offset;
40
41 return NULL;
42}
43
44static inline unsigned pin_to_mask(unsigned pin)
45{
46 pin -= PIN_BASE;
47 return 1 << (pin % 32);
48}
49
50
51/*--------------------------------------------------------------------------*/
52
53/* Not all hardware capabilities are exposed through these calls; they
54 * only encapsulate the most common features and modes. (So if you
55 * want to change signals in groups, do it directly.)
56 *
57 * Bootloaders will usually handle some of the pin multiplexing setup.
58 * The intent is certainly that by the time Linux is fully booted, all
59 * pins should have been fully initialized. These setup calls should
60 * only be used by board setup routines, or possibly in driver probe().
61 *
62 * For bootloaders doing all that setup, these calls could be inlined
63 * as NOPs so Linux won't duplicate any setup code
64 */
65
66
67/*
68 * mux the pin to the "GPIO" peripheral role.
69 */
70int __init_or_module at91_set_GPIO_periph(unsigned pin, int use_pullup)
71{
72 void __iomem *pio = pin_to_controller(pin);
73 unsigned mask = pin_to_mask(pin);
74
75 if (!pio)
76 return -EINVAL;
77 __raw_writel(mask, pio + PIO_IDR);
78 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
79 __raw_writel(mask, pio + PIO_PER);
80 return 0;
81}
82EXPORT_SYMBOL(at91_set_GPIO_periph);
83
84
85/*
86 * mux the pin to the "A" internal peripheral role.
87 */
88int __init_or_module at91_set_A_periph(unsigned pin, int use_pullup)
89{
90 void __iomem *pio = pin_to_controller(pin);
91 unsigned mask = pin_to_mask(pin);
92
93 if (!pio)
94 return -EINVAL;
95
96 __raw_writel(mask, pio + PIO_IDR);
97 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
98 __raw_writel(mask, pio + PIO_ASR);
99 __raw_writel(mask, pio + PIO_PDR);
100 return 0;
101}
102EXPORT_SYMBOL(at91_set_A_periph);
103
104
105/*
106 * mux the pin to the "B" internal peripheral role.
107 */
108int __init_or_module at91_set_B_periph(unsigned pin, int use_pullup)
109{
110 void __iomem *pio = pin_to_controller(pin);
111 unsigned mask = pin_to_mask(pin);
112
113 if (!pio)
114 return -EINVAL;
115
116 __raw_writel(mask, pio + PIO_IDR);
117 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
118 __raw_writel(mask, pio + PIO_BSR);
119 __raw_writel(mask, pio + PIO_PDR);
120 return 0;
121}
122EXPORT_SYMBOL(at91_set_B_periph);
123
124
125/*
126 * mux the pin to the gpio controller (instead of "A" or "B" peripheral), and
127 * configure it for an input.
128 */
129int __init_or_module at91_set_gpio_input(unsigned pin, int use_pullup)
130{
131 void __iomem *pio = pin_to_controller(pin);
132 unsigned mask = pin_to_mask(pin);
133
134 if (!pio)
135 return -EINVAL;
136
137 __raw_writel(mask, pio + PIO_IDR);
138 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
139 __raw_writel(mask, pio + PIO_ODR);
140 __raw_writel(mask, pio + PIO_PER);
141 return 0;
142}
143EXPORT_SYMBOL(at91_set_gpio_input);
144
145
146/*
147 * mux the pin to the gpio controller (instead of "A" or "B" peripheral),
148 * and configure it for an output.
149 */
150int __init_or_module at91_set_gpio_output(unsigned pin, int value)
151{
152 void __iomem *pio = pin_to_controller(pin);
153 unsigned mask = pin_to_mask(pin);
154
155 if (!pio)
156 return -EINVAL;
157
158 __raw_writel(mask, pio + PIO_IDR);
159 __raw_writel(mask, pio + PIO_PUDR);
160 __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
161 __raw_writel(mask, pio + PIO_OER);
162 __raw_writel(mask, pio + PIO_PER);
163 return 0;
164}
165EXPORT_SYMBOL(at91_set_gpio_output);
166
167
168/*
169 * enable/disable the glitch filter; mostly used with IRQ handling.
170 */
171int __init_or_module at91_set_deglitch(unsigned pin, int is_on)
172{
173 void __iomem *pio = pin_to_controller(pin);
174 unsigned mask = pin_to_mask(pin);
175
176 if (!pio)
177 return -EINVAL;
178 __raw_writel(mask, pio + (is_on ? PIO_IFER : PIO_IFDR));
179 return 0;
180}
181EXPORT_SYMBOL(at91_set_deglitch);
182
183/*
184 * enable/disable the multi-driver; This is only valid for output and
185 * allows the output pin to run as an open collector output.
186 */
187int __init_or_module at91_set_multi_drive(unsigned pin, int is_on)
188{
189 void __iomem *pio = pin_to_controller(pin);
190 unsigned mask = pin_to_mask(pin);
191
192 if (!pio)
193 return -EINVAL;
194
195 __raw_writel(mask, pio + (is_on ? PIO_MDER : PIO_MDDR));
196 return 0;
197}
198EXPORT_SYMBOL(at91_set_multi_drive);
199
200/*--------------------------------------------------------------------------*/
201
202/* new-style GPIO calls; these expect at91_set_GPIO_periph to have been
203 * called, and maybe at91_set_multi_drive() for putout pins.
204 */
205
206int gpio_direction_input(unsigned pin)
207{
208 void __iomem *pio = pin_to_controller(pin);
209 unsigned mask = pin_to_mask(pin);
210
211 if (!pio || !(__raw_readl(pio + PIO_PSR) & mask))
212 return -EINVAL;
213 __raw_writel(mask, pio + PIO_OER);
214 return 0;
215}
216EXPORT_SYMBOL(gpio_direction_input);
217
218int gpio_direction_output(unsigned pin)
219{
220 void __iomem *pio = pin_to_controller(pin);
221 unsigned mask = pin_to_mask(pin);
222
223 if (!pio || !(__raw_readl(pio + PIO_PSR) & mask))
224 return -EINVAL;
225 __raw_writel(mask, pio + PIO_OER);
226 return 0;
227}
228EXPORT_SYMBOL(gpio_direction_output);
229
230/*--------------------------------------------------------------------------*/
231
232/*
233 * assuming the pin is muxed as a gpio output, set its value.
234 */
235int at91_set_gpio_value(unsigned pin, int value)
236{
237 void __iomem *pio = pin_to_controller(pin);
238 unsigned mask = pin_to_mask(pin);
239
240 if (!pio)
241 return -EINVAL;
242 __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
243 return 0;
244}
245EXPORT_SYMBOL(at91_set_gpio_value);
246
247
248/*
249 * read the pin's value (works even if it's not muxed as a gpio).
250 */
251int at91_get_gpio_value(unsigned pin)
252{
253 void __iomem *pio = pin_to_controller(pin);
254 unsigned mask = pin_to_mask(pin);
255 u32 pdsr;
256
257 if (!pio)
258 return -EINVAL;
259 pdsr = __raw_readl(pio + PIO_PDSR);
260 return (pdsr & mask) != 0;
261}
262EXPORT_SYMBOL(at91_get_gpio_value);
263
264/*--------------------------------------------------------------------------*/
265
266#ifdef CONFIG_PM
267
268static u32 wakeups[MAX_GPIO_BANKS];
269static u32 backups[MAX_GPIO_BANKS];
270
271static int gpio_irq_set_wake(unsigned pin, unsigned state)
272{
273 unsigned mask = pin_to_mask(pin);
274 unsigned bank = (pin - PIN_BASE) / 32;
275
276 if (unlikely(bank >= MAX_GPIO_BANKS))
277 return -EINVAL;
278
279 if (state)
280 wakeups[bank] |= mask;
281 else
282 wakeups[bank] &= ~mask;
283
284 set_irq_wake(gpio[bank].id, state);
285
286 return 0;
287}
288
289void at91_gpio_suspend(void)
290{
291 int i;
292
293 for (i = 0; i < gpio_banks; i++) {
294 u32 pio = gpio[i].offset;
295
296 backups[i] = at91_sys_read(pio + PIO_IMR);
297 at91_sys_write(pio + PIO_IDR, backups[i]);
298 at91_sys_write(pio + PIO_IER, wakeups[i]);
299
300 if (!wakeups[i])
301 clk_disable(gpio[i].clock);
302 else {
303#ifdef CONFIG_PM_DEBUG
304 printk(KERN_DEBUG "GPIO-%c may wake for %08x\n", 'A'+i, wakeups[i]);
305#endif
306 }
307 }
308}
309
310void at91_gpio_resume(void)
311{
312 int i;
313
314 for (i = 0; i < gpio_banks; i++) {
315 u32 pio = gpio[i].offset;
316
317 if (!wakeups[i])
318 clk_enable(gpio[i].clock);
319
320 at91_sys_write(pio + PIO_IDR, wakeups[i]);
321 at91_sys_write(pio + PIO_IER, backups[i]);
322 }
323}
324
325#else
326#define gpio_irq_set_wake NULL
327#endif
328
329
330/* Several AIC controller irqs are dispatched through this GPIO handler.
331 * To use any AT91_PIN_* as an externally triggered IRQ, first call
332 * at91_set_gpio_input() then maybe enable its glitch filter.
333 * Then just request_irq() with the pin ID; it works like any ARM IRQ
334 * handler, though it always triggers on rising and falling edges.
335 *
336 * Alternatively, certain pins may be used directly as IRQ0..IRQ6 after
337 * configuring them with at91_set_a_periph() or at91_set_b_periph().
338 * IRQ0..IRQ6 should be configurable, e.g. level vs edge triggering.
339 */
340
341static void gpio_irq_mask(unsigned pin)
342{
343 void __iomem *pio = pin_to_controller(pin);
344 unsigned mask = pin_to_mask(pin);
345
346 if (pio)
347 __raw_writel(mask, pio + PIO_IDR);
348}
349
350static void gpio_irq_unmask(unsigned pin)
351{
352 void __iomem *pio = pin_to_controller(pin);
353 unsigned mask = pin_to_mask(pin);
354
355 if (pio)
356 __raw_writel(mask, pio + PIO_IER);
357}
358
359static int gpio_irq_type(unsigned pin, unsigned type)
360{
361 return (type == IRQT_BOTHEDGE) ? 0 : -EINVAL;
362}
363
364static struct irq_chip gpio_irqchip = {
365 .name = "GPIO",
366 .mask = gpio_irq_mask,
367 .unmask = gpio_irq_unmask,
368 .set_type = gpio_irq_type,
369 .set_wake = gpio_irq_set_wake,
370};
371
372static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
373{
374 unsigned pin;
375 struct irq_desc *gpio;
376 void __iomem *pio;
377 u32 isr;
378
379 pio = get_irq_chip_data(irq);
380
381 /* temporarily mask (level sensitive) parent IRQ */
382 desc->chip->ack(irq);
383 for (;;) {
384 /* reading ISR acks the pending (edge triggered) GPIO interrupt */
385 isr = __raw_readl(pio + PIO_ISR) & __raw_readl(pio + PIO_IMR);
386 if (!isr)
387 break;
388
389 pin = (unsigned) get_irq_data(irq);
390 gpio = &irq_desc[pin];
391
392 while (isr) {
393 if (isr & 1) {
394 if (unlikely(gpio->depth)) {
395 /*
396 * The core ARM interrupt handler lazily disables IRQs so
397 * another IRQ must be generated before it actually gets
398 * here to be disabled on the GPIO controller.
399 */
400 gpio_irq_mask(pin);
401 }
402 else
403 desc_handle_irq(pin, gpio);
404 }
405 pin++;
406 gpio++;
407 isr >>= 1;
408 }
409 }
410 desc->chip->unmask(irq);
411 /* now it may re-trigger */
412}
413
414/*--------------------------------------------------------------------------*/
415
416/*
417 * Called from the processor-specific init to enable GPIO interrupt support.
418 */
419void __init at91_gpio_irq_setup(void)
420{
421 unsigned pioc, pin;
422
423 for (pioc = 0, pin = PIN_BASE;
424 pioc < gpio_banks;
425 pioc++) {
426 void __iomem *controller;
427 unsigned id = gpio[pioc].id;
428 unsigned i;
429
430 clk_enable(gpio[pioc].clock); /* enable PIO controller's clock */
431
432 controller = (void __iomem *) AT91_VA_BASE_SYS + gpio[pioc].offset;
433 __raw_writel(~0, controller + PIO_IDR);
434
435 set_irq_data(id, (void *) pin);
436 set_irq_chip_data(id, controller);
437
438 for (i = 0; i < 32; i++, pin++) {
439 /*
440 * Can use the "simple" and not "edge" handler since it's
441 * shorter, and the AIC handles interupts sanely.
442 */
443 set_irq_chip(pin, &gpio_irqchip);
444 set_irq_handler(pin, handle_simple_irq);
445 set_irq_flags(pin, IRQF_VALID);
446 }
447
448 set_irq_chained_handler(id, gpio_irq_handler);
449 }
450 pr_info("AT91: %d gpio irqs in %d banks\n", pin - PIN_BASE, gpio_banks);
451}
452
453/*
454 * Called from the processor-specific init to enable GPIO pin support.
455 */
456void __init at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
457{
458 BUG_ON(nr_banks > MAX_GPIO_BANKS);
459
460 gpio = data;
461 gpio_banks = nr_banks;
462}