1 /*
2 * linux/arch/arm/mach-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/module.h>
17 #include <linux/irq.h>
18 #include <linux/sysdev.h>
19 #include <linux/io.h>
20
21 #include <asm/gpio.h>
22 #include <mach/hardware.h>
23 #include <mach/pxa-regs.h>
24 #include <mach/pxa2xx-gpio.h>
25
26 #include "generic.h"
27
28 #define GPIO0_BASE ((void __iomem *)io_p2v(0x40E00000))
29 #define GPIO1_BASE ((void __iomem *)io_p2v(0x40E00004))
30 #define GPIO2_BASE ((void __iomem *)io_p2v(0x40E00008))
31 #define GPIO3_BASE ((void __iomem *)io_p2v(0x40E00100))
32
33 #define GPLR_OFFSET 0x00
34 #define GPDR_OFFSET 0x0C
35 #define GPSR_OFFSET 0x18
36 #define GPCR_OFFSET 0x24
37 #define GRER_OFFSET 0x30
38 #define GFER_OFFSET 0x3C
39 #define GEDR_OFFSET 0x48
40
41 struct pxa_gpio_chip {
42 struct gpio_chip chip;
43 void __iomem *regbase;
44 };
45
46 int pxa_last_gpio;
47
48 #ifdef CONFIG_CPU_PXA26x
49 /* GPIO86/87/88/89 on PXA26x have their direction bits in GPDR2 inverted,
50 * as well as their Alternate Function value being '1' for GPIO in GAFRx.
51 */
__gpio_is_inverted(unsigned gpio)52 static int __gpio_is_inverted(unsigned gpio)
53 {
54 return cpu_is_pxa25x() && gpio > 85;
55 }
56 #else
57 #define __gpio_is_inverted(gpio) (0)
58 #endif
59
60 /*
61 * Configure pins for GPIO or other functions
62 */
pxa_gpio_mode(int gpio_mode)63 int pxa_gpio_mode(int gpio_mode)
64 {
65 unsigned long flags;
66 int gpio = gpio_mode & GPIO_MD_MASK_NR;
67 int fn = (gpio_mode & GPIO_MD_MASK_FN) >> 8;
68 int gafr;
69
70 if (gpio > pxa_last_gpio)
71 return -EINVAL;
72
73 local_irq_save(flags);
74 if (gpio_mode & GPIO_DFLT_LOW)
75 GPCR(gpio) = GPIO_bit(gpio);
76 else if (gpio_mode & GPIO_DFLT_HIGH)
77 GPSR(gpio) = GPIO_bit(gpio);
78 if (gpio_mode & GPIO_MD_MASK_DIR)
79 GPDR(gpio) |= GPIO_bit(gpio);
80 else
81 GPDR(gpio) &= ~GPIO_bit(gpio);
82 gafr = GAFR(gpio) & ~(0x3 << (((gpio) & 0xf)*2));
83 GAFR(gpio) = gafr | (fn << (((gpio) & 0xf)*2));
84 local_irq_restore(flags);
85
86 return 0;
87 }
88 EXPORT_SYMBOL(pxa_gpio_mode);
89
pxa_gpio_direction_input(struct gpio_chip * chip,unsigned offset)90 static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
91 {
92 unsigned long flags;
93 u32 mask = 1 << offset;
94 u32 value;
95 struct pxa_gpio_chip *pxa;
96 void __iomem *gpdr;
97
98 pxa = container_of(chip, struct pxa_gpio_chip, chip);
99 gpdr = pxa->regbase + GPDR_OFFSET;
100 local_irq_save(flags);
101 value = __raw_readl(gpdr);
102 if (__gpio_is_inverted(chip->base + offset))
103 value |= mask;
104 else
105 value &= ~mask;
106 __raw_writel(value, gpdr);
107 local_irq_restore(flags);
108
109 return 0;
110 }
111
pxa_gpio_direction_output(struct gpio_chip * chip,unsigned offset,int value)112 static int pxa_gpio_direction_output(struct gpio_chip *chip,
113 unsigned offset, int value)
114 {
115 unsigned long flags;
116 u32 mask = 1 << offset;
117 u32 tmp;
118 struct pxa_gpio_chip *pxa;
119 void __iomem *gpdr;
120
121 pxa = container_of(chip, struct pxa_gpio_chip, chip);
122 __raw_writel(mask,
123 pxa->regbase + (value ? GPSR_OFFSET : GPCR_OFFSET));
124 gpdr = pxa->regbase + GPDR_OFFSET;
125 local_irq_save(flags);
126 tmp = __raw_readl(gpdr);
127 if (__gpio_is_inverted(chip->base + offset))
128 tmp &= ~mask;
129 else
130 tmp |= mask;
131 __raw_writel(tmp, gpdr);
132 local_irq_restore(flags);
133
134 return 0;
135 }
136
137 /*
138 * Return GPIO level
139 */
pxa_gpio_get(struct gpio_chip * chip,unsigned offset)140 static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
141 {
142 u32 mask = 1 << offset;
143 struct pxa_gpio_chip *pxa;
144
145 pxa = container_of(chip, struct pxa_gpio_chip, chip);
146 return __raw_readl(pxa->regbase + GPLR_OFFSET) & mask;
147 }
148
149 /*
150 * Set output GPIO level
151 */
pxa_gpio_set(struct gpio_chip * chip,unsigned offset,int value)152 static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
153 {
154 u32 mask = 1 << offset;
155 struct pxa_gpio_chip *pxa;
156
157 pxa = container_of(chip, struct pxa_gpio_chip, chip);
158
159 if (value)
160 __raw_writel(mask, pxa->regbase + GPSR_OFFSET);
161 else
162 __raw_writel(mask, pxa->regbase + GPCR_OFFSET);
163 }
164
165 #define GPIO_CHIP(_n) \
166 [_n] = { \
167 .regbase = GPIO##_n##_BASE, \
168 .chip = { \
169 .label = "gpio-" #_n, \
170 .direction_input = pxa_gpio_direction_input, \
171 .direction_output = pxa_gpio_direction_output, \
172 .get = pxa_gpio_get, \
173 .set = pxa_gpio_set, \
174 .base = (_n) * 32, \
175 .ngpio = 32, \
176 }, \
177 }
178
179 static struct pxa_gpio_chip pxa_gpio_chip[] = {
180 GPIO_CHIP(0),
181 GPIO_CHIP(1),
182 GPIO_CHIP(2),
183 #if defined(CONFIG_PXA27x) || defined(CONFIG_PXA3xx)
184 GPIO_CHIP(3),
185 #endif
186 };
187
188 /*
189 * PXA GPIO edge detection for IRQs:
190 * IRQs are generated on Falling-Edge, Rising-Edge, or both.
191 * Use this instead of directly setting GRER/GFER.
192 */
193
194 static unsigned long GPIO_IRQ_rising_edge[4];
195 static unsigned long GPIO_IRQ_falling_edge[4];
196 static unsigned long GPIO_IRQ_mask[4];
197
198 /*
199 * On PXA25x and PXA27x, GAFRx and GPDRx together decide the alternate
200 * function of a GPIO, and GPDRx cannot be altered once configured. It
201 * is attributed as "occupied" here (I know this terminology isn't
202 * accurate, you are welcome to propose a better one :-)
203 */
__gpio_is_occupied(unsigned gpio)204 static int __gpio_is_occupied(unsigned gpio)
205 {
206 if (cpu_is_pxa27x() || cpu_is_pxa25x()) {
207 int af = (GAFR(gpio) >> ((gpio & 0xf) * 2)) & 0x3;
208 int dir = GPDR(gpio) & GPIO_bit(gpio);
209
210 if (__gpio_is_inverted(gpio))
211 return af != 1 || dir == 0;
212 else
213 return af != 0 || dir != 0;
214 }
215
216 return 0;
217 }
218
pxa_gpio_irq_type(unsigned int irq,unsigned int type)219 static int pxa_gpio_irq_type(unsigned int irq, unsigned int type)
220 {
221 int gpio, idx;
222
223 gpio = IRQ_TO_GPIO(irq);
224 idx = gpio >> 5;
225
226 if (type == IRQ_TYPE_PROBE) {
227 /* Don't mess with enabled GPIOs using preconfigured edges or
228 * GPIOs set to alternate function or to output during probe
229 */
230 if ((GPIO_IRQ_rising_edge[idx] & GPIO_bit(gpio)) ||
231 (GPIO_IRQ_falling_edge[idx] & GPIO_bit(gpio)))
232 return 0;
233
234 if (__gpio_is_occupied(gpio))
235 return 0;
236
237 type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
238 }
239
240 if (__gpio_is_inverted(gpio))
241 GPDR(gpio) |= GPIO_bit(gpio);
242 else
243 GPDR(gpio) &= ~GPIO_bit(gpio);
244
245 if (type & IRQ_TYPE_EDGE_RISING)
246 __set_bit(gpio, GPIO_IRQ_rising_edge);
247 else
248 __clear_bit(gpio, GPIO_IRQ_rising_edge);
249
250 if (type & IRQ_TYPE_EDGE_FALLING)
251 __set_bit(gpio, GPIO_IRQ_falling_edge);
252 else
253 __clear_bit(gpio, GPIO_IRQ_falling_edge);
254
255 GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
256 GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
257
258 pr_debug("%s: IRQ%d (GPIO%d) - edge%s%s\n", __func__, irq, gpio,
259 ((type & IRQ_TYPE_EDGE_RISING) ? " rising" : ""),
260 ((type & IRQ_TYPE_EDGE_FALLING) ? " falling" : ""));
261 return 0;
262 }
263
264 /*
265 * GPIO IRQs must be acknowledged. This is for GPIO 0 and 1.
266 */
267
pxa_ack_low_gpio(unsigned int irq)268 static void pxa_ack_low_gpio(unsigned int irq)
269 {
270 GEDR0 = (1 << (irq - IRQ_GPIO0));
271 }
272
pxa_mask_low_gpio(unsigned int irq)273 static void pxa_mask_low_gpio(unsigned int irq)
274 {
275 ICMR &= ~(1 << (irq - PXA_IRQ(0)));
276 }
277
pxa_unmask_low_gpio(unsigned int irq)278 static void pxa_unmask_low_gpio(unsigned int irq)
279 {
280 ICMR |= 1 << (irq - PXA_IRQ(0));
281 }
282
283 static struct irq_chip pxa_low_gpio_chip = {
284 .name = "GPIO-l",
285 .ack = pxa_ack_low_gpio,
286 .mask = pxa_mask_low_gpio,
287 .unmask = pxa_unmask_low_gpio,
288 .set_type = pxa_gpio_irq_type,
289 };
290
291 /*
292 * Demux handler for GPIO>=2 edge detect interrupts
293 */
294
295 #define GEDR_BITS (sizeof(gedr) * BITS_PER_BYTE)
296
pxa_gpio_demux_handler(unsigned int irq,struct irq_desc * desc)297 static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)
298 {
299 int loop, bit, n;
300 unsigned long gedr[4];
301
302 do {
303 gedr[0] = GEDR0 & GPIO_IRQ_mask[0] & ~3;
304 gedr[1] = GEDR1 & GPIO_IRQ_mask[1];
305 gedr[2] = GEDR2 & GPIO_IRQ_mask[2];
306 gedr[3] = GEDR3 & GPIO_IRQ_mask[3];
307
308 GEDR0 = gedr[0]; GEDR1 = gedr[1];
309 GEDR2 = gedr[2]; GEDR3 = gedr[3];
310
311 loop = 0;
312 bit = find_first_bit(gedr, GEDR_BITS);
313 while (bit < GEDR_BITS) {
314 loop = 1;
315
316 n = PXA_GPIO_IRQ_BASE + bit;
317 generic_handle_irq(n);
318
319 bit = find_next_bit(gedr, GEDR_BITS, bit + 1);
320 }
321 } while (loop);
322 }
323
pxa_ack_muxed_gpio(unsigned int irq)324 static void pxa_ack_muxed_gpio(unsigned int irq)
325 {
326 int gpio = irq - IRQ_GPIO(2) + 2;
327 GEDR(gpio) = GPIO_bit(gpio);
328 }
329
pxa_mask_muxed_gpio(unsigned int irq)330 static void pxa_mask_muxed_gpio(unsigned int irq)
331 {
332 int gpio = irq - IRQ_GPIO(2) + 2;
333 __clear_bit(gpio, GPIO_IRQ_mask);
334 GRER(gpio) &= ~GPIO_bit(gpio);
335 GFER(gpio) &= ~GPIO_bit(gpio);
336 }
337
pxa_unmask_muxed_gpio(unsigned int irq)338 static void pxa_unmask_muxed_gpio(unsigned int irq)
339 {
340 int gpio = irq - IRQ_GPIO(2) + 2;
341 int idx = gpio >> 5;
342 __set_bit(gpio, GPIO_IRQ_mask);
343 GRER(gpio) = GPIO_IRQ_rising_edge[idx] & GPIO_IRQ_mask[idx];
344 GFER(gpio) = GPIO_IRQ_falling_edge[idx] & GPIO_IRQ_mask[idx];
345 }
346
347 static struct irq_chip pxa_muxed_gpio_chip = {
348 .name = "GPIO",
349 .ack = pxa_ack_muxed_gpio,
350 .mask = pxa_mask_muxed_gpio,
351 .unmask = pxa_unmask_muxed_gpio,
352 .set_type = pxa_gpio_irq_type,
353 };
354
pxa_init_gpio(int gpio_nr,set_wake_t fn)355 void __init pxa_init_gpio(int gpio_nr, set_wake_t fn)
356 {
357 int irq, i, gpio;
358
359 pxa_last_gpio = gpio_nr - 1;
360
361 /* clear all GPIO edge detects */
362 for (i = 0; i < gpio_nr; i += 32) {
363 GFER(i) = 0;
364 GRER(i) = 0;
365 GEDR(i) = GEDR(i);
366 }
367
368 /* GPIO 0 and 1 must have their mask bit always set */
369 GPIO_IRQ_mask[0] = 3;
370
371 for (irq = IRQ_GPIO0; irq <= IRQ_GPIO1; irq++) {
372 set_irq_chip(irq, &pxa_low_gpio_chip);
373 set_irq_handler(irq, handle_edge_irq);
374 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
375 }
376
377 for (irq = IRQ_GPIO(2); irq < IRQ_GPIO(gpio_nr); irq++) {
378 set_irq_chip(irq, &pxa_muxed_gpio_chip);
379 set_irq_handler(irq, handle_edge_irq);
380 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
381 }
382
383 /* Install handler for GPIO>=2 edge detect interrupts */
384 set_irq_chained_handler(IRQ_GPIO_2_x, pxa_gpio_demux_handler);
385
386 pxa_low_gpio_chip.set_wake = fn;
387 pxa_muxed_gpio_chip.set_wake = fn;
388
389 /* add a GPIO chip for each register bank.
390 * the last PXA25x register only contains 21 GPIOs
391 */
392 for (gpio = 0, i = 0; gpio < gpio_nr; gpio += 32, i++) {
393 if (gpio + 32 > gpio_nr)
394 pxa_gpio_chip[i].chip.ngpio = gpio_nr - gpio;
395 gpiochip_add(&pxa_gpio_chip[i].chip);
396 }
397 }
398
399 #ifdef CONFIG_PM
400
401 static unsigned long saved_gplr[4];
402 static unsigned long saved_gpdr[4];
403 static unsigned long saved_grer[4];
404 static unsigned long saved_gfer[4];
405
pxa_gpio_suspend(struct sys_device * dev,pm_message_t state)406 static int pxa_gpio_suspend(struct sys_device *dev, pm_message_t state)
407 {
408 int i, gpio;
409
410 for (gpio = 0, i = 0; gpio < pxa_last_gpio; gpio += 32, i++) {
411 saved_gplr[i] = GPLR(gpio);
412 saved_gpdr[i] = GPDR(gpio);
413 saved_grer[i] = GRER(gpio);
414 saved_gfer[i] = GFER(gpio);
415
416 /* Clear GPIO transition detect bits */
417 GEDR(gpio) = GEDR(gpio);
418 }
419 return 0;
420 }
421
pxa_gpio_resume(struct sys_device * dev)422 static int pxa_gpio_resume(struct sys_device *dev)
423 {
424 int i, gpio;
425
426 for (gpio = 0, i = 0; gpio < pxa_last_gpio; gpio += 32, i++) {
427 /* restore level with set/clear */
428 GPSR(gpio) = saved_gplr[i];
429 GPCR(gpio) = ~saved_gplr[i];
430
431 GRER(gpio) = saved_grer[i];
432 GFER(gpio) = saved_gfer[i];
433 GPDR(gpio) = saved_gpdr[i];
434 }
435 return 0;
436 }
437 #else
438 #define pxa_gpio_suspend NULL
439 #define pxa_gpio_resume NULL
440 #endif
441
442 struct sysdev_class pxa_gpio_sysclass = {
443 .name = "gpio",
444 .suspend = pxa_gpio_suspend,
445 .resume = pxa_gpio_resume,
446 };
447
pxa_gpio_init(void)448 static int __init pxa_gpio_init(void)
449 {
450 return sysdev_class_register(&pxa_gpio_sysclass);
451 }
452
453 core_initcall(pxa_gpio_init);
454