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-rw-r--r--arch/arm/plat-pxa/gpio.c337
1 files changed, 337 insertions, 0 deletions
diff --git a/arch/arm/plat-pxa/gpio.c b/arch/arm/plat-pxa/gpio.c
new file mode 100644
index 000000000000..af819bf21b63
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+++ b/arch/arm/plat-pxa/gpio.c
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1/*
2 * linux/arch/arm/plat-pxa/gpio.c
3 *
4 * Generic PXA GPIO handling
5 *
6 * Author: Nicolas Pitre
7 * Created: Jun 15, 2001
8 * Copyright: MontaVista Software Inc.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14
15#include <linux/init.h>
16#include <linux/irq.h>
17#include <linux/io.h>
18#include <linux/sysdev.h>
19#include <linux/bootmem.h>
20
21#include <mach/gpio.h>
22
23int pxa_last_gpio;
24
25struct pxa_gpio_chip {
26 struct gpio_chip chip;
27 void __iomem *regbase;
28 char label[10];
29
30 unsigned long irq_mask;
31 unsigned long irq_edge_rise;
32 unsigned long irq_edge_fall;
33
34#ifdef CONFIG_PM
35 unsigned long saved_gplr;
36 unsigned long saved_gpdr;
37 unsigned long saved_grer;
38 unsigned long saved_gfer;
39#endif
40};
41
42static DEFINE_SPINLOCK(gpio_lock);
43static struct pxa_gpio_chip *pxa_gpio_chips;
44
45#define for_each_gpio_chip(i, c) \
46 for (i = 0, c = &pxa_gpio_chips[0]; i <= pxa_last_gpio; i += 32, c++)
47
48static inline void __iomem *gpio_chip_base(struct gpio_chip *c)
49{
50 return container_of(c, struct pxa_gpio_chip, chip)->regbase;
51}
52
53static inline struct pxa_gpio_chip *gpio_to_chip(unsigned gpio)
54{
55 return &pxa_gpio_chips[gpio_to_bank(gpio)];
56}
57
58static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
59{
60 void __iomem *base = gpio_chip_base(chip);
61 uint32_t value, mask = 1 << offset;
62 unsigned long flags;
63
64 spin_lock_irqsave(&gpio_lock, flags);
65
66 value = __raw_readl(base + GPDR_OFFSET);
67 if (__gpio_is_inverted(chip->base + offset))
68 value |= mask;
69 else
70 value &= ~mask;
71 __raw_writel(value, base + GPDR_OFFSET);
72
73 spin_unlock_irqrestore(&gpio_lock, flags);
74 return 0;
75}
76
77static int pxa_gpio_direction_output(struct gpio_chip *chip,
78 unsigned offset, int value)
79{
80 void __iomem *base = gpio_chip_base(chip);
81 uint32_t tmp, mask = 1 << offset;
82 unsigned long flags;
83
84 __raw_writel(mask, base + (value ? GPSR_OFFSET : GPCR_OFFSET));
85
86 spin_lock_irqsave(&gpio_lock, flags);
87
88 tmp = __raw_readl(base + GPDR_OFFSET);
89 if (__gpio_is_inverted(chip->base + offset))
90 tmp &= ~mask;
91 else
92 tmp |= mask;
93 __raw_writel(tmp, base + GPDR_OFFSET);
94
95 spin_unlock_irqrestore(&gpio_lock, flags);
96 return 0;
97}
98
99static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
100{
101 return __raw_readl(gpio_chip_base(chip) + GPLR_OFFSET) & (1 << offset);
102}
103
104static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
105{
106 __raw_writel(1 << offset, gpio_chip_base(chip) +
107 (value ? GPSR_OFFSET : GPCR_OFFSET));
108}
109
110static int __init pxa_init_gpio_chip(int gpio_end)
111{
112 int i, gpio, nbanks = gpio_to_bank(gpio_end) + 1;
113 struct pxa_gpio_chip *chips;
114
115 /* this is early, we have to use bootmem allocator, and we really
116 * want this to be allocated dynamically for different 'gpio_end'
117 */
118 chips = alloc_bootmem_low(nbanks * sizeof(struct pxa_gpio_chip));
119 if (chips == NULL) {
120 pr_err("%s: failed to allocate GPIO chips\n", __func__);
121 return -ENOMEM;
122 }
123
124 for (i = 0, gpio = 0; i < nbanks; i++, gpio += 32) {
125 struct gpio_chip *c = &chips[i].chip;
126
127 sprintf(chips[i].label, "gpio-%d", i);
128 chips[i].regbase = (void __iomem *)GPIO_BANK(i);
129
130 c->base = gpio;
131 c->label = chips[i].label;
132
133 c->direction_input = pxa_gpio_direction_input;
134 c->direction_output = pxa_gpio_direction_output;
135 c->get = pxa_gpio_get;
136 c->set = pxa_gpio_set;
137
138 /* number of GPIOs on last bank may be less than 32 */
139 c->ngpio = (gpio + 31 > gpio_end) ? (gpio_end - gpio + 1) : 32;
140 gpiochip_add(c);
141 }
142 pxa_gpio_chips = chips;
143 return 0;
144}
145
146static int pxa_gpio_irq_type(unsigned int irq, unsigned int type)
147{
148 struct pxa_gpio_chip *c;
149 int gpio = irq_to_gpio(irq);
150 unsigned long gpdr, mask = GPIO_bit(gpio);
151
152 c = gpio_to_chip(gpio);
153
154 if (type == IRQ_TYPE_PROBE) {
155 /* Don't mess with enabled GPIOs using preconfigured edges or
156 * GPIOs set to alternate function or to output during probe
157 */
158 if ((c->irq_edge_rise | c->irq_edge_fall) & GPIO_bit(gpio))
159 return 0;
160
161 if (__gpio_is_occupied(gpio))
162 return 0;
163
164 type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
165 }
166
167 gpdr = __raw_readl(c->regbase + GPDR_OFFSET);
168
169 if (__gpio_is_inverted(gpio))
170 __raw_writel(gpdr | mask, c->regbase + GPDR_OFFSET);
171 else
172 __raw_writel(gpdr & ~mask, c->regbase + GPDR_OFFSET);
173
174 if (type & IRQ_TYPE_EDGE_RISING)
175 c->irq_edge_rise |= mask;
176 else
177 c->irq_edge_rise &= ~mask;
178
179 if (type & IRQ_TYPE_EDGE_FALLING)
180 c->irq_edge_fall |= mask;
181 else
182 c->irq_edge_fall &= ~mask;
183
184 __raw_writel(c->irq_edge_rise & c->irq_mask, c->regbase + GRER_OFFSET);
185 __raw_writel(c->irq_edge_fall & c->irq_mask, c->regbase + GFER_OFFSET);
186
187 pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, irq, gpio,
188 ((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
189 ((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
190 return 0;
191}
192
193static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
194{
195 struct pxa_gpio_chip *c;
196 int loop, gpio, gpio_base, n;
197 unsigned long gedr;
198
199 do {
200 loop = 0;
201 for_each_gpio_chip(gpio, c) {
202 gpio_base = c->chip.base;
203
204 gedr = __raw_readl(c->regbase + GEDR_OFFSET);
205 gedr = gedr & c->irq_mask;
206 __raw_writel(gedr, c->regbase + GEDR_OFFSET);
207
208 n = find_first_bit(&gedr, BITS_PER_LONG);
209 while (n < BITS_PER_LONG) {
210 loop = 1;
211
212 generic_handle_irq(gpio_to_irq(gpio_base + n));
213 n = find_next_bit(&gedr, BITS_PER_LONG, n + 1);
214 }
215 }
216 } while (loop);
217}
218
219static void pxa_ack_muxed_gpio(unsigned int irq)
220{
221 int gpio = irq_to_gpio(irq);
222 struct pxa_gpio_chip *c = gpio_to_chip(gpio);
223
224 __raw_writel(GPIO_bit(gpio), c->regbase + GEDR_OFFSET);
225}
226
227static void pxa_mask_muxed_gpio(unsigned int irq)
228{
229 int gpio = irq_to_gpio(irq);
230 struct pxa_gpio_chip *c = gpio_to_chip(gpio);
231 uint32_t grer, gfer;
232
233 c->irq_mask &= ~GPIO_bit(gpio);
234
235 grer = __raw_readl(c->regbase + GRER_OFFSET) & ~GPIO_bit(gpio);
236 gfer = __raw_readl(c->regbase + GFER_OFFSET) & ~GPIO_bit(gpio);
237 __raw_writel(grer, c->regbase + GRER_OFFSET);
238 __raw_writel(gfer, c->regbase + GFER_OFFSET);
239}
240
241static void pxa_unmask_muxed_gpio(unsigned int irq)
242{
243 int gpio = irq_to_gpio(irq);
244 struct pxa_gpio_chip *c = gpio_to_chip(gpio);
245
246 c->irq_mask |= GPIO_bit(gpio);
247 __raw_writel(c->irq_edge_rise & c->irq_mask, c->regbase + GRER_OFFSET);
248 __raw_writel(c->irq_edge_fall & c->irq_mask, c->regbase + GFER_OFFSET);
249}
250
251static struct irq_chip pxa_muxed_gpio_chip = {
252 .name = "GPIO",
253 .ack = pxa_ack_muxed_gpio,
254 .mask = pxa_mask_muxed_gpio,
255 .unmask = pxa_unmask_muxed_gpio,
256 .set_type = pxa_gpio_irq_type,
257};
258
259void __init pxa_init_gpio(int mux_irq, int start, int end, set_wake_t fn)
260{
261 struct pxa_gpio_chip *c;
262 int gpio, irq;
263
264 pxa_last_gpio = end;
265
266 /* Initialize GPIO chips */
267 pxa_init_gpio_chip(end);
268
269 /* clear all GPIO edge detects */
270 for_each_gpio_chip(gpio, c) {
271 __raw_writel(0, c->regbase + GFER_OFFSET);
272 __raw_writel(0, c->regbase + GRER_OFFSET);
273 __raw_writel(~0,c->regbase + GEDR_OFFSET);
274 }
275
276 for (irq = gpio_to_irq(start); irq <= gpio_to_irq(end); irq++) {
277 set_irq_chip(irq, &pxa_muxed_gpio_chip);
278 set_irq_handler(irq, handle_edge_irq);
279 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
280 }
281
282 /* Install handler for GPIO>=2 edge detect interrupts */
283 set_irq_chained_handler(mux_irq, pxa_gpio_demux_handler);
284 pxa_muxed_gpio_chip.set_wake = fn;
285}
286
287#ifdef CONFIG_PM
288static int pxa_gpio_suspend(struct sys_device *dev, pm_message_t state)
289{
290 struct pxa_gpio_chip *c;
291 int gpio;
292
293 for_each_gpio_chip(gpio, c) {
294 c->saved_gplr = __raw_readl(c->regbase + GPLR_OFFSET);
295 c->saved_gpdr = __raw_readl(c->regbase + GPDR_OFFSET);
296 c->saved_grer = __raw_readl(c->regbase + GRER_OFFSET);
297 c->saved_gfer = __raw_readl(c->regbase + GFER_OFFSET);
298
299 /* Clear GPIO transition detect bits */
300 __raw_writel(0xffffffff, c->regbase + GEDR_OFFSET);
301 }
302 return 0;
303}
304
305static int pxa_gpio_resume(struct sys_device *dev)
306{
307 struct pxa_gpio_chip *c;
308 int gpio;
309
310 for_each_gpio_chip(gpio, c) {
311 /* restore level with set/clear */
312 __raw_writel( c->saved_gplr, c->regbase + GPSR_OFFSET);
313 __raw_writel(~c->saved_gplr, c->regbase + GPCR_OFFSET);
314
315 __raw_writel(c->saved_grer, c->regbase + GRER_OFFSET);
316 __raw_writel(c->saved_gfer, c->regbase + GFER_OFFSET);
317 __raw_writel(c->saved_gpdr, c->regbase + GPDR_OFFSET);
318 }
319 return 0;
320}
321#else
322#define pxa_gpio_suspend NULL
323#define pxa_gpio_resume NULL
324#endif
325
326struct sysdev_class pxa_gpio_sysclass = {
327 .name = "gpio",
328 .suspend = pxa_gpio_suspend,
329 .resume = pxa_gpio_resume,
330};
331
332static int __init pxa_gpio_init(void)
333{
334 return sysdev_class_register(&pxa_gpio_sysclass);
335}
336
337core_initcall(pxa_gpio_init);