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authorAndrew Victor <andrew@sanpeople.com>2007-02-05 05:42:07 -0500
committerRussell King <rmk+kernel@arm.linux.org.uk>2007-02-08 09:50:56 -0500
commit9d0412680e6c7b685ee466842047bcfb924d6dc5 (patch)
treec79300964ef1aca5d24571696f95e76b37c14679 /arch/arm/mach-at91/gpio.c
parenta93d48cc6019f84394b31d10c0d830a3b71696be (diff)
[ARM] 4124/1: Rename mach-at91rm9200 and arch-at91rm9200 directories
Now that Linux includes support for the Atmel AT91SAM9260 and AT91SAM9261 processors in addition to the original Atmel AT91RM9200 (with support for more AT91 processors pending), the "mach-at91rm9200" and "arch-at91rm9200" directories should be renamed to indicate their more generic nature. The following git commands should be run BEFORE applying this patch: git-mv arch/arm/mach-at91rm9200 arch/arm/mach-at91 git-mv include/asm-arm/arch-at91rm9200 include/asm-arm/arch-at91 Signed-off-by: Andrew Victor <andrew@sanpeople.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-at91/gpio.c')
-rw-r--r--arch/arm/mach-at91/gpio.c414
1 files changed, 414 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..9b7495cd555d
--- /dev/null
+++ b/arch/arm/mach-at91/gpio.c
@@ -0,0 +1,414 @@
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 "A" internal peripheral role.
69 */
70int __init_or_module at91_set_A_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
78 __raw_writel(mask, pio + PIO_IDR);
79 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
80 __raw_writel(mask, pio + PIO_ASR);
81 __raw_writel(mask, pio + PIO_PDR);
82 return 0;
83}
84EXPORT_SYMBOL(at91_set_A_periph);
85
86
87/*
88 * mux the pin to the "B" internal peripheral role.
89 */
90int __init_or_module at91_set_B_periph(unsigned pin, int use_pullup)
91{
92 void __iomem *pio = pin_to_controller(pin);
93 unsigned mask = pin_to_mask(pin);
94
95 if (!pio)
96 return -EINVAL;
97
98 __raw_writel(mask, pio + PIO_IDR);
99 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
100 __raw_writel(mask, pio + PIO_BSR);
101 __raw_writel(mask, pio + PIO_PDR);
102 return 0;
103}
104EXPORT_SYMBOL(at91_set_B_periph);
105
106
107/*
108 * mux the pin to the gpio controller (instead of "A" or "B" peripheral), and
109 * configure it for an input.
110 */
111int __init_or_module at91_set_gpio_input(unsigned pin, int use_pullup)
112{
113 void __iomem *pio = pin_to_controller(pin);
114 unsigned mask = pin_to_mask(pin);
115
116 if (!pio)
117 return -EINVAL;
118
119 __raw_writel(mask, pio + PIO_IDR);
120 __raw_writel(mask, pio + (use_pullup ? PIO_PUER : PIO_PUDR));
121 __raw_writel(mask, pio + PIO_ODR);
122 __raw_writel(mask, pio + PIO_PER);
123 return 0;
124}
125EXPORT_SYMBOL(at91_set_gpio_input);
126
127
128/*
129 * mux the pin to the gpio controller (instead of "A" or "B" peripheral),
130 * and configure it for an output.
131 */
132int __init_or_module at91_set_gpio_output(unsigned pin, int value)
133{
134 void __iomem *pio = pin_to_controller(pin);
135 unsigned mask = pin_to_mask(pin);
136
137 if (!pio)
138 return -EINVAL;
139
140 __raw_writel(mask, pio + PIO_IDR);
141 __raw_writel(mask, pio + PIO_PUDR);
142 __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
143 __raw_writel(mask, pio + PIO_OER);
144 __raw_writel(mask, pio + PIO_PER);
145 return 0;
146}
147EXPORT_SYMBOL(at91_set_gpio_output);
148
149
150/*
151 * enable/disable the glitch filter; mostly used with IRQ handling.
152 */
153int __init_or_module at91_set_deglitch(unsigned pin, int is_on)
154{
155 void __iomem *pio = pin_to_controller(pin);
156 unsigned mask = pin_to_mask(pin);
157
158 if (!pio)
159 return -EINVAL;
160 __raw_writel(mask, pio + (is_on ? PIO_IFER : PIO_IFDR));
161 return 0;
162}
163EXPORT_SYMBOL(at91_set_deglitch);
164
165/*
166 * enable/disable the multi-driver; This is only valid for output and
167 * allows the output pin to run as an open collector output.
168 */
169int __init_or_module at91_set_multi_drive(unsigned pin, int is_on)
170{
171 void __iomem *pio = pin_to_controller(pin);
172 unsigned mask = pin_to_mask(pin);
173
174 if (!pio)
175 return -EINVAL;
176
177 __raw_writel(mask, pio + (is_on ? PIO_MDER : PIO_MDDR));
178 return 0;
179}
180EXPORT_SYMBOL(at91_set_multi_drive);
181
182/*--------------------------------------------------------------------------*/
183
184/*
185 * assuming the pin is muxed as a gpio output, set its value.
186 */
187int at91_set_gpio_value(unsigned pin, int value)
188{
189 void __iomem *pio = pin_to_controller(pin);
190 unsigned mask = pin_to_mask(pin);
191
192 if (!pio)
193 return -EINVAL;
194 __raw_writel(mask, pio + (value ? PIO_SODR : PIO_CODR));
195 return 0;
196}
197EXPORT_SYMBOL(at91_set_gpio_value);
198
199
200/*
201 * read the pin's value (works even if it's not muxed as a gpio).
202 */
203int at91_get_gpio_value(unsigned pin)
204{
205 void __iomem *pio = pin_to_controller(pin);
206 unsigned mask = pin_to_mask(pin);
207 u32 pdsr;
208
209 if (!pio)
210 return -EINVAL;
211 pdsr = __raw_readl(pio + PIO_PDSR);
212 return (pdsr & mask) != 0;
213}
214EXPORT_SYMBOL(at91_get_gpio_value);
215
216/*--------------------------------------------------------------------------*/
217
218#ifdef CONFIG_PM
219
220static u32 wakeups[MAX_GPIO_BANKS];
221static u32 backups[MAX_GPIO_BANKS];
222
223static int gpio_irq_set_wake(unsigned pin, unsigned state)
224{
225 unsigned mask = pin_to_mask(pin);
226 unsigned bank = (pin - PIN_BASE) / 32;
227
228 if (unlikely(bank >= MAX_GPIO_BANKS))
229 return -EINVAL;
230
231 if (state)
232 wakeups[bank] |= mask;
233 else
234 wakeups[bank] &= ~mask;
235
236 set_irq_wake(gpio[bank].id, state);
237
238 return 0;
239}
240
241void at91_gpio_suspend(void)
242{
243 int i;
244
245 for (i = 0; i < gpio_banks; i++) {
246 u32 pio = gpio[i].offset;
247
248 backups[i] = at91_sys_read(pio + PIO_IMR);
249 at91_sys_write(pio + PIO_IDR, backups[i]);
250 at91_sys_write(pio + PIO_IER, wakeups[i]);
251
252 if (!wakeups[i])
253 clk_disable(gpio[i].clock);
254 else {
255#ifdef CONFIG_PM_DEBUG
256 printk(KERN_DEBUG "GPIO-%c may wake for %08x\n", 'A'+i, wakeups[i]);
257#endif
258 }
259 }
260}
261
262void at91_gpio_resume(void)
263{
264 int i;
265
266 for (i = 0; i < gpio_banks; i++) {
267 u32 pio = gpio[i].offset;
268
269 if (!wakeups[i])
270 clk_enable(gpio[i].clock);
271
272 at91_sys_write(pio + PIO_IDR, wakeups[i]);
273 at91_sys_write(pio + PIO_IER, backups[i]);
274 }
275}
276
277#else
278#define gpio_irq_set_wake NULL
279#endif
280
281
282/* Several AIC controller irqs are dispatched through this GPIO handler.
283 * To use any AT91_PIN_* as an externally triggered IRQ, first call
284 * at91_set_gpio_input() then maybe enable its glitch filter.
285 * Then just request_irq() with the pin ID; it works like any ARM IRQ
286 * handler, though it always triggers on rising and falling edges.
287 *
288 * Alternatively, certain pins may be used directly as IRQ0..IRQ6 after
289 * configuring them with at91_set_a_periph() or at91_set_b_periph().
290 * IRQ0..IRQ6 should be configurable, e.g. level vs edge triggering.
291 */
292
293static void gpio_irq_mask(unsigned pin)
294{
295 void __iomem *pio = pin_to_controller(pin);
296 unsigned mask = pin_to_mask(pin);
297
298 if (pio)
299 __raw_writel(mask, pio + PIO_IDR);
300}
301
302static void gpio_irq_unmask(unsigned pin)
303{
304 void __iomem *pio = pin_to_controller(pin);
305 unsigned mask = pin_to_mask(pin);
306
307 if (pio)
308 __raw_writel(mask, pio + PIO_IER);
309}
310
311static int gpio_irq_type(unsigned pin, unsigned type)
312{
313 return (type == IRQT_BOTHEDGE) ? 0 : -EINVAL;
314}
315
316static struct irq_chip gpio_irqchip = {
317 .name = "GPIO",
318 .mask = gpio_irq_mask,
319 .unmask = gpio_irq_unmask,
320 .set_type = gpio_irq_type,
321 .set_wake = gpio_irq_set_wake,
322};
323
324static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
325{
326 unsigned pin;
327 struct irq_desc *gpio;
328 void __iomem *pio;
329 u32 isr;
330
331 pio = get_irq_chip_data(irq);
332
333 /* temporarily mask (level sensitive) parent IRQ */
334 desc->chip->ack(irq);
335 for (;;) {
336 /* reading ISR acks the pending (edge triggered) GPIO interrupt */
337 isr = __raw_readl(pio + PIO_ISR) & __raw_readl(pio + PIO_IMR);
338 if (!isr)
339 break;
340
341 pin = (unsigned) get_irq_data(irq);
342 gpio = &irq_desc[pin];
343
344 while (isr) {
345 if (isr & 1) {
346 if (unlikely(gpio->depth)) {
347 /*
348 * The core ARM interrupt handler lazily disables IRQs so
349 * another IRQ must be generated before it actually gets
350 * here to be disabled on the GPIO controller.
351 */
352 gpio_irq_mask(pin);
353 }
354 else
355 desc_handle_irq(pin, gpio);
356 }
357 pin++;
358 gpio++;
359 isr >>= 1;
360 }
361 }
362 desc->chip->unmask(irq);
363 /* now it may re-trigger */
364}
365
366/*--------------------------------------------------------------------------*/
367
368/*
369 * Called from the processor-specific init to enable GPIO interrupt support.
370 */
371void __init at91_gpio_irq_setup(void)
372{
373 unsigned pioc, pin;
374
375 for (pioc = 0, pin = PIN_BASE;
376 pioc < gpio_banks;
377 pioc++) {
378 void __iomem *controller;
379 unsigned id = gpio[pioc].id;
380 unsigned i;
381
382 clk_enable(gpio[pioc].clock); /* enable PIO controller's clock */
383
384 controller = (void __iomem *) AT91_VA_BASE_SYS + gpio[pioc].offset;
385 __raw_writel(~0, controller + PIO_IDR);
386
387 set_irq_data(id, (void *) pin);
388 set_irq_chip_data(id, controller);
389
390 for (i = 0; i < 32; i++, pin++) {
391 /*
392 * Can use the "simple" and not "edge" handler since it's
393 * shorter, and the AIC handles interupts sanely.
394 */
395 set_irq_chip(pin, &gpio_irqchip);
396 set_irq_handler(pin, handle_simple_irq);
397 set_irq_flags(pin, IRQF_VALID);
398 }
399
400 set_irq_chained_handler(id, gpio_irq_handler);
401 }
402 pr_info("AT91: %d gpio irqs in %d banks\n", pin - PIN_BASE, gpio_banks);
403}
404
405/*
406 * Called from the processor-specific init to enable GPIO pin support.
407 */
408void __init at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
409{
410 BUG_ON(nr_banks > MAX_GPIO_BANKS);
411
412 gpio = data;
413 gpio_banks = nr_banks;
414}