tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Driver for NEC VR4100 series General-purpose I/O Unit.
3 *
4 * Copyright (C) 2002 MontaVista Software Inc.
5 * Author: Yoichi Yuasa <yyuasa@mvista.com or source@mvista.com>
6 * Copyright (C) 2003-2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22#include <linux/errno.h>
23#include <linux/fs.h>
24#include <linux/init.h>
25#include <linux/interrupt.h>
26#include <linux/irq.h>
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/platform_device.h>
30#include <linux/smp_lock.h>
31#include <linux/spinlock.h>
32#include <linux/types.h>
33
34#include <asm/io.h>
35#include <asm/vr41xx/giu.h>
36#include <asm/vr41xx/irq.h>
37#include <asm/vr41xx/vr41xx.h>
38
39MODULE_AUTHOR("Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>");
40MODULE_DESCRIPTION("NEC VR4100 series General-purpose I/O Unit driver");
41MODULE_LICENSE("GPL");
42
43static int major; /* default is dynamic major device number */
44module_param(major, int, 0);
45MODULE_PARM_DESC(major, "Major device number");
46
47#define GIUIOSELL 0x00
48#define GIUIOSELH 0x02
49#define GIUPIODL 0x04
50#define GIUPIODH 0x06
51#define GIUINTSTATL 0x08
52#define GIUINTSTATH 0x0a
53#define GIUINTENL 0x0c
54#define GIUINTENH 0x0e
55#define GIUINTTYPL 0x10
56#define GIUINTTYPH 0x12
57#define GIUINTALSELL 0x14
58#define GIUINTALSELH 0x16
59#define GIUINTHTSELL 0x18
60#define GIUINTHTSELH 0x1a
61#define GIUPODATL 0x1c
62#define GIUPODATEN 0x1c
63#define GIUPODATH 0x1e
64 #define PIOEN0 0x0100
65 #define PIOEN1 0x0200
66#define GIUPODAT 0x1e
67#define GIUFEDGEINHL 0x20
68#define GIUFEDGEINHH 0x22
69#define GIUREDGEINHL 0x24
70#define GIUREDGEINHH 0x26
71
72#define GIUUSEUPDN 0x1e0
73#define GIUTERMUPDN 0x1e2
74
75#define GPIO_HAS_PULLUPDOWN_IO 0x0001
76#define GPIO_HAS_OUTPUT_ENABLE 0x0002
77#define GPIO_HAS_INTERRUPT_EDGE_SELECT 0x0100
78
79static spinlock_t giu_lock;
80static unsigned long giu_flags;
81static unsigned int giu_nr_pins;
82
83static void __iomem *giu_base;
84
85#define giu_read(offset) readw(giu_base + (offset))
86#define giu_write(offset, value) writew((value), giu_base + (offset))
87
88#define GPIO_PIN_OF_IRQ(irq) ((irq) - GIU_IRQ_BASE)
89#define GIUINT_HIGH_OFFSET 16
90#define GIUINT_HIGH_MAX 32
91
92static inline uint16_t giu_set(uint16_t offset, uint16_t set)
93{
94 uint16_t data;
95
96 data = giu_read(offset);
97 data |= set;
98 giu_write(offset, data);
99
100 return data;
101}
102
103static inline uint16_t giu_clear(uint16_t offset, uint16_t clear)
104{
105 uint16_t data;
106
107 data = giu_read(offset);
108 data &= ~clear;
109 giu_write(offset, data);
110
111 return data;
112}
113
114static void ack_giuint_low(unsigned int irq)
115{
116 giu_write(GIUINTSTATL, 1 << GPIO_PIN_OF_IRQ(irq));
117}
118
119static void mask_giuint_low(unsigned int irq)
120{
121 giu_clear(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
122}
123
124static void mask_ack_giuint_low(unsigned int irq)
125{
126 unsigned int pin;
127
128 pin = GPIO_PIN_OF_IRQ(irq);
129 giu_clear(GIUINTENL, 1 << pin);
130 giu_write(GIUINTSTATL, 1 << pin);
131}
132
133static void unmask_giuint_low(unsigned int irq)
134{
135 giu_set(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
136}
137
138static struct irq_chip giuint_low_irq_chip = {
139 .name = "GIUINTL",
140 .ack = ack_giuint_low,
141 .mask = mask_giuint_low,
142 .mask_ack = mask_ack_giuint_low,
143 .unmask = unmask_giuint_low,
144};
145
146static void ack_giuint_high(unsigned int irq)
147{
148 giu_write(GIUINTSTATH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
149}
150
151static void mask_giuint_high(unsigned int irq)
152{
153 giu_clear(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
154}
155
156static void mask_ack_giuint_high(unsigned int irq)
157{
158 unsigned int pin;
159
160 pin = GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET;
161 giu_clear(GIUINTENH, 1 << pin);
162 giu_write(GIUINTSTATH, 1 << pin);
163}
164
165static void unmask_giuint_high(unsigned int irq)
166{
167 giu_set(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
168}
169
170static struct irq_chip giuint_high_irq_chip = {
171 .name = "GIUINTH",
172 .ack = ack_giuint_high,
173 .mask = mask_giuint_high,
174 .mask_ack = mask_ack_giuint_high,
175 .unmask = unmask_giuint_high,
176};
177
178static int giu_get_irq(unsigned int irq)
179{
180 uint16_t pendl, pendh, maskl, maskh;
181 int i;
182
183 pendl = giu_read(GIUINTSTATL);
184 pendh = giu_read(GIUINTSTATH);
185 maskl = giu_read(GIUINTENL);
186 maskh = giu_read(GIUINTENH);
187
188 maskl &= pendl;
189 maskh &= pendh;
190
191 if (maskl) {
192 for (i = 0; i < 16; i++) {
193 if (maskl & (1 << i))
194 return GIU_IRQ(i);
195 }
196 } else if (maskh) {
197 for (i = 0; i < 16; i++) {
198 if (maskh & (1 << i))
199 return GIU_IRQ(i + GIUINT_HIGH_OFFSET);
200 }
201 }
202
203 printk(KERN_ERR "spurious GIU interrupt: %04x(%04x),%04x(%04x)\n",
204 maskl, pendl, maskh, pendh);
205
206 atomic_inc(&irq_err_count);
207
208 return -EINVAL;
209}
210
211void vr41xx_set_irq_trigger(unsigned int pin, irq_trigger_t trigger, irq_signal_t signal)
212{
213 uint16_t mask;
214
215 if (pin < GIUINT_HIGH_OFFSET) {
216 mask = 1 << pin;
217 if (trigger != IRQ_TRIGGER_LEVEL) {
218 giu_set(GIUINTTYPL, mask);
219 if (signal == IRQ_SIGNAL_HOLD)
220 giu_set(GIUINTHTSELL, mask);
221 else
222 giu_clear(GIUINTHTSELL, mask);
223 if (giu_flags & GPIO_HAS_INTERRUPT_EDGE_SELECT) {
224 switch (trigger) {
225 case IRQ_TRIGGER_EDGE_FALLING:
226 giu_set(GIUFEDGEINHL, mask);
227 giu_clear(GIUREDGEINHL, mask);
228 break;
229 case IRQ_TRIGGER_EDGE_RISING:
230 giu_clear(GIUFEDGEINHL, mask);
231 giu_set(GIUREDGEINHL, mask);
232 break;
233 default:
234 giu_set(GIUFEDGEINHL, mask);
235 giu_set(GIUREDGEINHL, mask);
236 break;
237 }
238 }
239 set_irq_chip_and_handler(GIU_IRQ(pin),
240 &giuint_low_irq_chip,
241 handle_edge_irq);
242 } else {
243 giu_clear(GIUINTTYPL, mask);
244 giu_clear(GIUINTHTSELL, mask);
245 set_irq_chip_and_handler(GIU_IRQ(pin),
246 &giuint_low_irq_chip,
247 handle_level_irq);
248 }
249 giu_write(GIUINTSTATL, mask);
250 } else if (pin < GIUINT_HIGH_MAX) {
251 mask = 1 << (pin - GIUINT_HIGH_OFFSET);
252 if (trigger != IRQ_TRIGGER_LEVEL) {
253 giu_set(GIUINTTYPH, mask);
254 if (signal == IRQ_SIGNAL_HOLD)
255 giu_set(GIUINTHTSELH, mask);
256 else
257 giu_clear(GIUINTHTSELH, mask);
258 if (giu_flags & GPIO_HAS_INTERRUPT_EDGE_SELECT) {
259 switch (trigger) {
260 case IRQ_TRIGGER_EDGE_FALLING:
261 giu_set(GIUFEDGEINHH, mask);
262 giu_clear(GIUREDGEINHH, mask);
263 break;
264 case IRQ_TRIGGER_EDGE_RISING:
265 giu_clear(GIUFEDGEINHH, mask);
266 giu_set(GIUREDGEINHH, mask);
267 break;
268 default:
269 giu_set(GIUFEDGEINHH, mask);
270 giu_set(GIUREDGEINHH, mask);
271 break;
272 }
273 }
274 set_irq_chip_and_handler(GIU_IRQ(pin),
275 &giuint_high_irq_chip,
276 handle_edge_irq);
277 } else {
278 giu_clear(GIUINTTYPH, mask);
279 giu_clear(GIUINTHTSELH, mask);
280 set_irq_chip_and_handler(GIU_IRQ(pin),
281 &giuint_high_irq_chip,
282 handle_level_irq);
283 }
284 giu_write(GIUINTSTATH, mask);
285 }
286}
287EXPORT_SYMBOL_GPL(vr41xx_set_irq_trigger);
288
289void vr41xx_set_irq_level(unsigned int pin, irq_level_t level)
290{
291 uint16_t mask;
292
293 if (pin < GIUINT_HIGH_OFFSET) {
294 mask = 1 << pin;
295 if (level == IRQ_LEVEL_HIGH)
296 giu_set(GIUINTALSELL, mask);
297 else
298 giu_clear(GIUINTALSELL, mask);
299 giu_write(GIUINTSTATL, mask);
300 } else if (pin < GIUINT_HIGH_MAX) {
301 mask = 1 << (pin - GIUINT_HIGH_OFFSET);
302 if (level == IRQ_LEVEL_HIGH)
303 giu_set(GIUINTALSELH, mask);
304 else
305 giu_clear(GIUINTALSELH, mask);
306 giu_write(GIUINTSTATH, mask);
307 }
308}
309EXPORT_SYMBOL_GPL(vr41xx_set_irq_level);
310
311gpio_data_t vr41xx_gpio_get_pin(unsigned int pin)
312{
313 uint16_t reg, mask;
314
315 if (pin >= giu_nr_pins)
316 return GPIO_DATA_INVAL;
317
318 if (pin < 16) {
319 reg = giu_read(GIUPIODL);
320 mask = (uint16_t)1 << pin;
321 } else if (pin < 32) {
322 reg = giu_read(GIUPIODH);
323 mask = (uint16_t)1 << (pin - 16);
324 } else if (pin < 48) {
325 reg = giu_read(GIUPODATL);
326 mask = (uint16_t)1 << (pin - 32);
327 } else {
328 reg = giu_read(GIUPODATH);
329 mask = (uint16_t)1 << (pin - 48);
330 }
331
332 if (reg & mask)
333 return GPIO_DATA_HIGH;
334
335 return GPIO_DATA_LOW;
336}
337EXPORT_SYMBOL_GPL(vr41xx_gpio_get_pin);
338
339int vr41xx_gpio_set_pin(unsigned int pin, gpio_data_t data)
340{
341 uint16_t offset, mask, reg;
342 unsigned long flags;
343
344 if (pin >= giu_nr_pins)
345 return -EINVAL;
346
347 if (pin < 16) {
348 offset = GIUPIODL;
349 mask = (uint16_t)1 << pin;
350 } else if (pin < 32) {
351 offset = GIUPIODH;
352 mask = (uint16_t)1 << (pin - 16);
353 } else if (pin < 48) {
354 offset = GIUPODATL;
355 mask = (uint16_t)1 << (pin - 32);
356 } else {
357 offset = GIUPODATH;
358 mask = (uint16_t)1 << (pin - 48);
359 }
360
361 spin_lock_irqsave(&giu_lock, flags);
362
363 reg = giu_read(offset);
364 if (data == GPIO_DATA_HIGH)
365 reg |= mask;
366 else
367 reg &= ~mask;
368 giu_write(offset, reg);
369
370 spin_unlock_irqrestore(&giu_lock, flags);
371
372 return 0;
373}
374EXPORT_SYMBOL_GPL(vr41xx_gpio_set_pin);
375
376int vr41xx_gpio_set_direction(unsigned int pin, gpio_direction_t dir)
377{
378 uint16_t offset, mask, reg;
379 unsigned long flags;
380
381 if (pin >= giu_nr_pins)
382 return -EINVAL;
383
384 if (pin < 16) {
385 offset = GIUIOSELL;
386 mask = (uint16_t)1 << pin;
387 } else if (pin < 32) {
388 offset = GIUIOSELH;
389 mask = (uint16_t)1 << (pin - 16);
390 } else {
391 if (giu_flags & GPIO_HAS_OUTPUT_ENABLE) {
392 offset = GIUPODATEN;
393 mask = (uint16_t)1 << (pin - 32);
394 } else {
395 switch (pin) {
396 case 48:
397 offset = GIUPODATH;
398 mask = PIOEN0;
399 break;
400 case 49:
401 offset = GIUPODATH;
402 mask = PIOEN1;
403 break;
404 default:
405 return -EINVAL;
406 }
407 }
408 }
409
410 spin_lock_irqsave(&giu_lock, flags);
411
412 reg = giu_read(offset);
413 if (dir == GPIO_OUTPUT)
414 reg |= mask;
415 else
416 reg &= ~mask;
417 giu_write(offset, reg);
418
419 spin_unlock_irqrestore(&giu_lock, flags);
420
421 return 0;
422}
423EXPORT_SYMBOL_GPL(vr41xx_gpio_set_direction);
424
425int vr41xx_gpio_pullupdown(unsigned int pin, gpio_pull_t pull)
426{
427 uint16_t reg, mask;
428 unsigned long flags;
429
430 if ((giu_flags & GPIO_HAS_PULLUPDOWN_IO) != GPIO_HAS_PULLUPDOWN_IO)
431 return -EPERM;
432
433 if (pin >= 15)
434 return -EINVAL;
435
436 mask = (uint16_t)1 << pin;
437
438 spin_lock_irqsave(&giu_lock, flags);
439
440 if (pull == GPIO_PULL_UP || pull == GPIO_PULL_DOWN) {
441 reg = giu_read(GIUTERMUPDN);
442 if (pull == GPIO_PULL_UP)
443 reg |= mask;
444 else
445 reg &= ~mask;
446 giu_write(GIUTERMUPDN, reg);
447
448 reg = giu_read(GIUUSEUPDN);
449 reg |= mask;
450 giu_write(GIUUSEUPDN, reg);
451 } else {
452 reg = giu_read(GIUUSEUPDN);
453 reg &= ~mask;
454 giu_write(GIUUSEUPDN, reg);
455 }
456
457 spin_unlock_irqrestore(&giu_lock, flags);
458
459 return 0;
460}
461EXPORT_SYMBOL_GPL(vr41xx_gpio_pullupdown);
462
463static ssize_t gpio_read(struct file *file, char __user *buf, size_t len,
464 loff_t *ppos)
465{
466 unsigned int pin;
467 char value = '0';
468
469 pin = iminor(file->f_path.dentry->d_inode);
470 if (pin >= giu_nr_pins)
471 return -EBADF;
472
473 if (vr41xx_gpio_get_pin(pin) == GPIO_DATA_HIGH)
474 value = '1';
475
476 if (len <= 0)
477 return -EFAULT;
478
479 if (put_user(value, buf))
480 return -EFAULT;
481
482 return 1;
483}
484
485static ssize_t gpio_write(struct file *file, const char __user *data,
486 size_t len, loff_t *ppos)
487{
488 unsigned int pin;
489 size_t i;
490 char c;
491 int retval = 0;
492
493 pin = iminor(file->f_path.dentry->d_inode);
494 if (pin >= giu_nr_pins)
495 return -EBADF;
496
497 for (i = 0; i < len; i++) {
498 if (get_user(c, data + i))
499 return -EFAULT;
500
501 switch (c) {
502 case '0':
503 retval = vr41xx_gpio_set_pin(pin, GPIO_DATA_LOW);
504 break;
505 case '1':
506 retval = vr41xx_gpio_set_pin(pin, GPIO_DATA_HIGH);
507 break;
508 case 'D':
509 printk(KERN_INFO "GPIO%d: pull down\n", pin);
510 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DOWN);
511 break;
512 case 'd':
513 printk(KERN_INFO "GPIO%d: pull up/down disable\n", pin);
514 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DISABLE);
515 break;
516 case 'I':
517 printk(KERN_INFO "GPIO%d: input\n", pin);
518 retval = vr41xx_gpio_set_direction(pin, GPIO_INPUT);
519 break;
520 case 'O':
521 printk(KERN_INFO "GPIO%d: output\n", pin);
522 retval = vr41xx_gpio_set_direction(pin, GPIO_OUTPUT);
523 break;
524 case 'o':
525 printk(KERN_INFO "GPIO%d: output disable\n", pin);
526 retval = vr41xx_gpio_set_direction(pin, GPIO_OUTPUT_DISABLE);
527 break;
528 case 'P':
529 printk(KERN_INFO "GPIO%d: pull up\n", pin);
530 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_UP);
531 break;
532 case 'p':
533 printk(KERN_INFO "GPIO%d: pull up/down disable\n", pin);
534 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DISABLE);
535 break;
536 default:
537 break;
538 }
539
540 if (retval < 0)
541 break;
542 }
543
544 return i;
545}
546
547static int gpio_open(struct inode *inode, struct file *file)
548{
549 unsigned int pin;
550
551 cycle_kernel_lock();
552 pin = iminor(inode);
553 if (pin >= giu_nr_pins)
554 return -EBADF;
555
556 return nonseekable_open(inode, file);
557}
558
559static int gpio_release(struct inode *inode, struct file *file)
560{
561 unsigned int pin;
562
563 pin = iminor(inode);
564 if (pin >= giu_nr_pins)
565 return -EBADF;
566
567 return 0;
568}
569
570static const struct file_operations gpio_fops = {
571 .owner = THIS_MODULE,
572 .read = gpio_read,
573 .write = gpio_write,
574 .open = gpio_open,
575 .release = gpio_release,
576};
577
578static int __devinit giu_probe(struct platform_device *dev)
579{
580 struct resource *res;
581 unsigned int trigger, i, pin;
582 struct irq_chip *chip;
583 int irq, retval;
584
585 switch (dev->id) {
586 case GPIO_50PINS_PULLUPDOWN:
587 giu_flags = GPIO_HAS_PULLUPDOWN_IO;
588 giu_nr_pins = 50;
589 break;
590 case GPIO_36PINS:
591 giu_nr_pins = 36;
592 break;
593 case GPIO_48PINS_EDGE_SELECT:
594 giu_flags = GPIO_HAS_INTERRUPT_EDGE_SELECT;
595 giu_nr_pins = 48;
596 break;
597 default:
598 printk(KERN_ERR "GIU: unknown ID %d\n", dev->id);
599 return -ENODEV;
600 }
601
602 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
603 if (!res)
604 return -EBUSY;
605
606 giu_base = ioremap(res->start, res->end - res->start + 1);
607 if (!giu_base)
608 return -ENOMEM;
609
610 retval = register_chrdev(major, "GIU", &gpio_fops);
611 if (retval < 0) {
612 iounmap(giu_base);
613 giu_base = NULL;
614 return retval;
615 }
616
617 if (major == 0) {
618 major = retval;
619 printk(KERN_INFO "GIU: major number %d\n", major);
620 }
621
622 spin_lock_init(&giu_lock);
623
624 giu_write(GIUINTENL, 0);
625 giu_write(GIUINTENH, 0);
626
627 trigger = giu_read(GIUINTTYPH) << 16;
628 trigger |= giu_read(GIUINTTYPL);
629 for (i = GIU_IRQ_BASE; i <= GIU_IRQ_LAST; i++) {
630 pin = GPIO_PIN_OF_IRQ(i);
631 if (pin < GIUINT_HIGH_OFFSET)
632 chip = &giuint_low_irq_chip;
633 else
634 chip = &giuint_high_irq_chip;
635
636 if (trigger & (1 << pin))
637 set_irq_chip_and_handler(i, chip, handle_edge_irq);
638 else
639 set_irq_chip_and_handler(i, chip, handle_level_irq);
640
641 }
642
643 irq = platform_get_irq(dev, 0);
644 if (irq < 0 || irq >= nr_irqs)
645 return -EBUSY;
646
647 return cascade_irq(irq, giu_get_irq);
648}
649
650static int __devexit giu_remove(struct platform_device *dev)
651{
652 if (giu_base) {
653 iounmap(giu_base);
654 giu_base = NULL;
655 }
656
657 return 0;
658}
659
660static struct platform_driver giu_device_driver = {
661 .probe = giu_probe,
662 .remove = __devexit_p(giu_remove),
663 .driver = {
664 .name = "GIU",
665 .owner = THIS_MODULE,
666 },
667};
668
669static int __init vr41xx_giu_init(void)
670{
671 return platform_driver_register(&giu_device_driver);
672}
673
674static void __exit vr41xx_giu_exit(void)
675{
676 platform_driver_unregister(&giu_device_driver);
677}
678
679module_init(vr41xx_giu_init);
680module_exit(vr41xx_giu_exit);