[NET_SCHED]: Fix endless loops caused by inaccurate qlen counters (part 1)
[hh.org.git] / drivers / char / vr41xx_giu.c
blob8e794930517111ec3013f79f0f486c1ad7998265
1 /*
2 * Driver for NEC VR4100 series General-purpose I/O Unit.
4 * Copyright (C) 2002 MontaVista Software Inc.
5 * Author: Yoichi Yuasa <yyuasa@mvista.com or source@mvista.com>
6 * Copyright (C) 2003-2005 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
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.
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.
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
22 #include <linux/platform_device.h>
23 #include <linux/errno.h>
24 #include <linux/fs.h>
25 #include <linux/init.h>
26 #include <linux/irq.h>
27 #include <linux/interrupt.h>
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/spinlock.h>
31 #include <linux/types.h>
33 #include <asm/cpu.h>
34 #include <asm/io.h>
35 #include <asm/vr41xx/giu.h>
36 #include <asm/vr41xx/irq.h>
37 #include <asm/vr41xx/vr41xx.h>
39 MODULE_AUTHOR("Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>");
40 MODULE_DESCRIPTION("NEC VR4100 series General-purpose I/O Unit driver");
41 MODULE_LICENSE("GPL");
43 static int major; /* default is dynamic major device number */
44 module_param(major, int, 0);
45 MODULE_PARM_DESC(major, "Major device number");
47 #define GIU_TYPE1_START 0x0b000100UL
48 #define GIU_TYPE1_SIZE 0x20UL
50 #define GIU_TYPE2_START 0x0f000140UL
51 #define GIU_TYPE2_SIZE 0x20UL
53 #define GIU_TYPE3_START 0x0f000140UL
54 #define GIU_TYPE3_SIZE 0x28UL
56 #define GIU_PULLUPDOWN_START 0x0b0002e0UL
57 #define GIU_PULLUPDOWN_SIZE 0x04UL
59 #define GIUIOSELL 0x00
60 #define GIUIOSELH 0x02
61 #define GIUPIODL 0x04
62 #define GIUPIODH 0x06
63 #define GIUINTSTATL 0x08
64 #define GIUINTSTATH 0x0a
65 #define GIUINTENL 0x0c
66 #define GIUINTENH 0x0e
67 #define GIUINTTYPL 0x10
68 #define GIUINTTYPH 0x12
69 #define GIUINTALSELL 0x14
70 #define GIUINTALSELH 0x16
71 #define GIUINTHTSELL 0x18
72 #define GIUINTHTSELH 0x1a
73 #define GIUPODATL 0x1c
74 #define GIUPODATEN 0x1c
75 #define GIUPODATH 0x1e
76 #define PIOEN0 0x0100
77 #define PIOEN1 0x0200
78 #define GIUPODAT 0x1e
79 #define GIUFEDGEINHL 0x20
80 #define GIUFEDGEINHH 0x22
81 #define GIUREDGEINHL 0x24
82 #define GIUREDGEINHH 0x26
84 #define GIUUSEUPDN 0x1e0
85 #define GIUTERMUPDN 0x1e2
87 #define GPIO_HAS_PULLUPDOWN_IO 0x0001
88 #define GPIO_HAS_OUTPUT_ENABLE 0x0002
89 #define GPIO_HAS_INTERRUPT_EDGE_SELECT 0x0100
91 static spinlock_t giu_lock;
92 static struct resource *giu_resource1;
93 static struct resource *giu_resource2;
94 static unsigned long giu_flags;
95 static unsigned int giu_nr_pins;
97 static void __iomem *giu_base;
99 #define giu_read(offset) readw(giu_base + (offset))
100 #define giu_write(offset, value) writew((value), giu_base + (offset))
102 #define GPIO_PIN_OF_IRQ(irq) ((irq) - GIU_IRQ_BASE)
103 #define GIUINT_HIGH_OFFSET 16
104 #define GIUINT_HIGH_MAX 32
106 static inline uint16_t giu_set(uint16_t offset, uint16_t set)
108 uint16_t data;
110 data = giu_read(offset);
111 data |= set;
112 giu_write(offset, data);
114 return data;
117 static inline uint16_t giu_clear(uint16_t offset, uint16_t clear)
119 uint16_t data;
121 data = giu_read(offset);
122 data &= ~clear;
123 giu_write(offset, data);
125 return data;
128 static unsigned int startup_giuint_low_irq(unsigned int irq)
130 unsigned int pin;
132 pin = GPIO_PIN_OF_IRQ(irq);
133 giu_write(GIUINTSTATL, 1 << pin);
134 giu_set(GIUINTENL, 1 << pin);
136 return 0;
139 static void shutdown_giuint_low_irq(unsigned int irq)
141 giu_clear(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
144 static void enable_giuint_low_irq(unsigned int irq)
146 giu_set(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
149 #define disable_giuint_low_irq shutdown_giuint_low_irq
151 static void ack_giuint_low_irq(unsigned int irq)
153 unsigned int pin;
155 pin = GPIO_PIN_OF_IRQ(irq);
156 giu_clear(GIUINTENL, 1 << pin);
157 giu_write(GIUINTSTATL, 1 << pin);
160 static void end_giuint_low_irq(unsigned int irq)
162 if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
163 giu_set(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
166 static struct hw_interrupt_type giuint_low_irq_type = {
167 .typename = "GIUINTL",
168 .startup = startup_giuint_low_irq,
169 .shutdown = shutdown_giuint_low_irq,
170 .enable = enable_giuint_low_irq,
171 .disable = disable_giuint_low_irq,
172 .ack = ack_giuint_low_irq,
173 .end = end_giuint_low_irq,
176 static unsigned int startup_giuint_high_irq(unsigned int irq)
178 unsigned int pin;
180 pin = GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET;
181 giu_write(GIUINTSTATH, 1 << pin);
182 giu_set(GIUINTENH, 1 << pin);
184 return 0;
187 static void shutdown_giuint_high_irq(unsigned int irq)
189 giu_clear(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
192 static void enable_giuint_high_irq(unsigned int irq)
194 giu_set(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
197 #define disable_giuint_high_irq shutdown_giuint_high_irq
199 static void ack_giuint_high_irq(unsigned int irq)
201 unsigned int pin;
203 pin = GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET;
204 giu_clear(GIUINTENH, 1 << pin);
205 giu_write(GIUINTSTATH, 1 << pin);
208 static void end_giuint_high_irq(unsigned int irq)
210 if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
211 giu_set(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
214 static struct hw_interrupt_type giuint_high_irq_type = {
215 .typename = "GIUINTH",
216 .startup = startup_giuint_high_irq,
217 .shutdown = shutdown_giuint_high_irq,
218 .enable = enable_giuint_high_irq,
219 .disable = disable_giuint_high_irq,
220 .ack = ack_giuint_high_irq,
221 .end = end_giuint_high_irq,
224 static int giu_get_irq(unsigned int irq)
226 uint16_t pendl, pendh, maskl, maskh;
227 int i;
229 pendl = giu_read(GIUINTSTATL);
230 pendh = giu_read(GIUINTSTATH);
231 maskl = giu_read(GIUINTENL);
232 maskh = giu_read(GIUINTENH);
234 maskl &= pendl;
235 maskh &= pendh;
237 if (maskl) {
238 for (i = 0; i < 16; i++) {
239 if (maskl & (1 << i))
240 return GIU_IRQ(i);
242 } else if (maskh) {
243 for (i = 0; i < 16; i++) {
244 if (maskh & (1 << i))
245 return GIU_IRQ(i + GIUINT_HIGH_OFFSET);
249 printk(KERN_ERR "spurious GIU interrupt: %04x(%04x),%04x(%04x)\n",
250 maskl, pendl, maskh, pendh);
252 atomic_inc(&irq_err_count);
254 return -EINVAL;
257 void vr41xx_set_irq_trigger(unsigned int pin, irq_trigger_t trigger, irq_signal_t signal)
259 uint16_t mask;
261 if (pin < GIUINT_HIGH_OFFSET) {
262 mask = 1 << pin;
263 if (trigger != IRQ_TRIGGER_LEVEL) {
264 giu_set(GIUINTTYPL, mask);
265 if (signal == IRQ_SIGNAL_HOLD)
266 giu_set(GIUINTHTSELL, mask);
267 else
268 giu_clear(GIUINTHTSELL, mask);
269 if (current_cpu_data.cputype == CPU_VR4133) {
270 switch (trigger) {
271 case IRQ_TRIGGER_EDGE_FALLING:
272 giu_set(GIUFEDGEINHL, mask);
273 giu_clear(GIUREDGEINHL, mask);
274 break;
275 case IRQ_TRIGGER_EDGE_RISING:
276 giu_clear(GIUFEDGEINHL, mask);
277 giu_set(GIUREDGEINHL, mask);
278 break;
279 default:
280 giu_set(GIUFEDGEINHL, mask);
281 giu_set(GIUREDGEINHL, mask);
282 break;
285 } else {
286 giu_clear(GIUINTTYPL, mask);
287 giu_clear(GIUINTHTSELL, mask);
289 giu_write(GIUINTSTATL, mask);
290 } else if (pin < GIUINT_HIGH_MAX) {
291 mask = 1 << (pin - GIUINT_HIGH_OFFSET);
292 if (trigger != IRQ_TRIGGER_LEVEL) {
293 giu_set(GIUINTTYPH, mask);
294 if (signal == IRQ_SIGNAL_HOLD)
295 giu_set(GIUINTHTSELH, mask);
296 else
297 giu_clear(GIUINTHTSELH, mask);
298 if (current_cpu_data.cputype == CPU_VR4133) {
299 switch (trigger) {
300 case IRQ_TRIGGER_EDGE_FALLING:
301 giu_set(GIUFEDGEINHH, mask);
302 giu_clear(GIUREDGEINHH, mask);
303 break;
304 case IRQ_TRIGGER_EDGE_RISING:
305 giu_clear(GIUFEDGEINHH, mask);
306 giu_set(GIUREDGEINHH, mask);
307 break;
308 default:
309 giu_set(GIUFEDGEINHH, mask);
310 giu_set(GIUREDGEINHH, mask);
311 break;
314 } else {
315 giu_clear(GIUINTTYPH, mask);
316 giu_clear(GIUINTHTSELH, mask);
318 giu_write(GIUINTSTATH, mask);
322 EXPORT_SYMBOL_GPL(vr41xx_set_irq_trigger);
324 void vr41xx_set_irq_level(unsigned int pin, irq_level_t level)
326 uint16_t mask;
328 if (pin < GIUINT_HIGH_OFFSET) {
329 mask = 1 << pin;
330 if (level == IRQ_LEVEL_HIGH)
331 giu_set(GIUINTALSELL, mask);
332 else
333 giu_clear(GIUINTALSELL, mask);
334 giu_write(GIUINTSTATL, mask);
335 } else if (pin < GIUINT_HIGH_MAX) {
336 mask = 1 << (pin - GIUINT_HIGH_OFFSET);
337 if (level == IRQ_LEVEL_HIGH)
338 giu_set(GIUINTALSELH, mask);
339 else
340 giu_clear(GIUINTALSELH, mask);
341 giu_write(GIUINTSTATH, mask);
345 EXPORT_SYMBOL_GPL(vr41xx_set_irq_level);
347 gpio_data_t vr41xx_gpio_get_pin(unsigned int pin)
349 uint16_t reg, mask;
351 if (pin >= giu_nr_pins)
352 return GPIO_DATA_INVAL;
354 if (pin < 16) {
355 reg = giu_read(GIUPIODL);
356 mask = (uint16_t)1 << pin;
357 } else if (pin < 32) {
358 reg = giu_read(GIUPIODH);
359 mask = (uint16_t)1 << (pin - 16);
360 } else if (pin < 48) {
361 reg = giu_read(GIUPODATL);
362 mask = (uint16_t)1 << (pin - 32);
363 } else {
364 reg = giu_read(GIUPODATH);
365 mask = (uint16_t)1 << (pin - 48);
368 if (reg & mask)
369 return GPIO_DATA_HIGH;
371 return GPIO_DATA_LOW;
374 EXPORT_SYMBOL_GPL(vr41xx_gpio_get_pin);
376 int vr41xx_gpio_set_pin(unsigned int pin, gpio_data_t data)
378 uint16_t offset, mask, reg;
379 unsigned long flags;
381 if (pin >= giu_nr_pins)
382 return -EINVAL;
384 if (pin < 16) {
385 offset = GIUPIODL;
386 mask = (uint16_t)1 << pin;
387 } else if (pin < 32) {
388 offset = GIUPIODH;
389 mask = (uint16_t)1 << (pin - 16);
390 } else if (pin < 48) {
391 offset = GIUPODATL;
392 mask = (uint16_t)1 << (pin - 32);
393 } else {
394 offset = GIUPODATH;
395 mask = (uint16_t)1 << (pin - 48);
398 spin_lock_irqsave(&giu_lock, flags);
400 reg = giu_read(offset);
401 if (data == GPIO_DATA_HIGH)
402 reg |= mask;
403 else
404 reg &= ~mask;
405 giu_write(offset, reg);
407 spin_unlock_irqrestore(&giu_lock, flags);
409 return 0;
412 EXPORT_SYMBOL_GPL(vr41xx_gpio_set_pin);
414 int vr41xx_gpio_set_direction(unsigned int pin, gpio_direction_t dir)
416 uint16_t offset, mask, reg;
417 unsigned long flags;
419 if (pin >= giu_nr_pins)
420 return -EINVAL;
422 if (pin < 16) {
423 offset = GIUIOSELL;
424 mask = (uint16_t)1 << pin;
425 } else if (pin < 32) {
426 offset = GIUIOSELH;
427 mask = (uint16_t)1 << (pin - 16);
428 } else {
429 if (giu_flags & GPIO_HAS_OUTPUT_ENABLE) {
430 offset = GIUPODATEN;
431 mask = (uint16_t)1 << (pin - 32);
432 } else {
433 switch (pin) {
434 case 48:
435 offset = GIUPODATH;
436 mask = PIOEN0;
437 break;
438 case 49:
439 offset = GIUPODATH;
440 mask = PIOEN1;
441 break;
442 default:
443 return -EINVAL;
448 spin_lock_irqsave(&giu_lock, flags);
450 reg = giu_read(offset);
451 if (dir == GPIO_OUTPUT)
452 reg |= mask;
453 else
454 reg &= ~mask;
455 giu_write(offset, reg);
457 spin_unlock_irqrestore(&giu_lock, flags);
459 return 0;
462 EXPORT_SYMBOL_GPL(vr41xx_gpio_set_direction);
464 int vr41xx_gpio_pullupdown(unsigned int pin, gpio_pull_t pull)
466 uint16_t reg, mask;
467 unsigned long flags;
469 if ((giu_flags & GPIO_HAS_PULLUPDOWN_IO) != GPIO_HAS_PULLUPDOWN_IO)
470 return -EPERM;
472 if (pin >= 15)
473 return -EINVAL;
475 mask = (uint16_t)1 << pin;
477 spin_lock_irqsave(&giu_lock, flags);
479 if (pull == GPIO_PULL_UP || pull == GPIO_PULL_DOWN) {
480 reg = giu_read(GIUTERMUPDN);
481 if (pull == GPIO_PULL_UP)
482 reg |= mask;
483 else
484 reg &= ~mask;
485 giu_write(GIUTERMUPDN, reg);
487 reg = giu_read(GIUUSEUPDN);
488 reg |= mask;
489 giu_write(GIUUSEUPDN, reg);
490 } else {
491 reg = giu_read(GIUUSEUPDN);
492 reg &= ~mask;
493 giu_write(GIUUSEUPDN, reg);
496 spin_unlock_irqrestore(&giu_lock, flags);
498 return 0;
501 EXPORT_SYMBOL_GPL(vr41xx_gpio_pullupdown);
503 static ssize_t gpio_read(struct file *file, char __user *buf, size_t len,
504 loff_t *ppos)
506 unsigned int pin;
507 char value = '0';
509 pin = iminor(file->f_dentry->d_inode);
510 if (pin >= giu_nr_pins)
511 return -EBADF;
513 if (vr41xx_gpio_get_pin(pin) == GPIO_DATA_HIGH)
514 value = '1';
516 if (len <= 0)
517 return -EFAULT;
519 if (put_user(value, buf))
520 return -EFAULT;
522 return 1;
525 static ssize_t gpio_write(struct file *file, const char __user *data,
526 size_t len, loff_t *ppos)
528 unsigned int pin;
529 size_t i;
530 char c;
531 int retval = 0;
533 pin = iminor(file->f_dentry->d_inode);
534 if (pin >= giu_nr_pins)
535 return -EBADF;
537 for (i = 0; i < len; i++) {
538 if (get_user(c, data + i))
539 return -EFAULT;
541 switch (c) {
542 case '0':
543 retval = vr41xx_gpio_set_pin(pin, GPIO_DATA_LOW);
544 break;
545 case '1':
546 retval = vr41xx_gpio_set_pin(pin, GPIO_DATA_HIGH);
547 break;
548 case 'D':
549 printk(KERN_INFO "GPIO%d: pull down\n", pin);
550 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DOWN);
551 break;
552 case 'd':
553 printk(KERN_INFO "GPIO%d: pull up/down disable\n", pin);
554 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DISABLE);
555 break;
556 case 'I':
557 printk(KERN_INFO "GPIO%d: input\n", pin);
558 retval = vr41xx_gpio_set_direction(pin, GPIO_INPUT);
559 break;
560 case 'O':
561 printk(KERN_INFO "GPIO%d: output\n", pin);
562 retval = vr41xx_gpio_set_direction(pin, GPIO_OUTPUT);
563 break;
564 case 'o':
565 printk(KERN_INFO "GPIO%d: output disable\n", pin);
566 retval = vr41xx_gpio_set_direction(pin, GPIO_OUTPUT_DISABLE);
567 break;
568 case 'P':
569 printk(KERN_INFO "GPIO%d: pull up\n", pin);
570 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_UP);
571 break;
572 case 'p':
573 printk(KERN_INFO "GPIO%d: pull up/down disable\n", pin);
574 retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DISABLE);
575 break;
576 default:
577 break;
580 if (retval < 0)
581 break;
584 return i;
587 static int gpio_open(struct inode *inode, struct file *file)
589 unsigned int pin;
591 pin = iminor(inode);
592 if (pin >= giu_nr_pins)
593 return -EBADF;
595 return nonseekable_open(inode, file);
598 static int gpio_release(struct inode *inode, struct file *file)
600 unsigned int pin;
602 pin = iminor(inode);
603 if (pin >= giu_nr_pins)
604 return -EBADF;
606 return 0;
609 static const struct file_operations gpio_fops = {
610 .owner = THIS_MODULE,
611 .read = gpio_read,
612 .write = gpio_write,
613 .open = gpio_open,
614 .release = gpio_release,
617 static int __devinit giu_probe(struct platform_device *dev)
619 unsigned long start, size, flags = 0;
620 unsigned int nr_pins = 0;
621 struct resource *res1, *res2 = NULL;
622 void *base;
623 int retval, i;
625 switch (current_cpu_data.cputype) {
626 case CPU_VR4111:
627 case CPU_VR4121:
628 start = GIU_TYPE1_START;
629 size = GIU_TYPE1_SIZE;
630 flags = GPIO_HAS_PULLUPDOWN_IO;
631 nr_pins = 50;
632 break;
633 case CPU_VR4122:
634 case CPU_VR4131:
635 start = GIU_TYPE2_START;
636 size = GIU_TYPE2_SIZE;
637 nr_pins = 36;
638 break;
639 case CPU_VR4133:
640 start = GIU_TYPE3_START;
641 size = GIU_TYPE3_SIZE;
642 flags = GPIO_HAS_INTERRUPT_EDGE_SELECT;
643 nr_pins = 48;
644 break;
645 default:
646 return -ENODEV;
649 res1 = request_mem_region(start, size, "GIU");
650 if (res1 == NULL)
651 return -EBUSY;
653 base = ioremap(start, size);
654 if (base == NULL) {
655 release_resource(res1);
656 return -ENOMEM;
659 if (flags & GPIO_HAS_PULLUPDOWN_IO) {
660 res2 = request_mem_region(GIU_PULLUPDOWN_START, GIU_PULLUPDOWN_SIZE, "GIU");
661 if (res2 == NULL) {
662 iounmap(base);
663 release_resource(res1);
664 return -EBUSY;
668 retval = register_chrdev(major, "GIU", &gpio_fops);
669 if (retval < 0) {
670 iounmap(base);
671 release_resource(res1);
672 release_resource(res2);
673 return retval;
676 if (major == 0) {
677 major = retval;
678 printk(KERN_INFO "GIU: major number %d\n", major);
681 spin_lock_init(&giu_lock);
682 giu_base = base;
683 giu_resource1 = res1;
684 giu_resource2 = res2;
685 giu_flags = flags;
686 giu_nr_pins = nr_pins;
688 giu_write(GIUINTENL, 0);
689 giu_write(GIUINTENH, 0);
691 for (i = GIU_IRQ_BASE; i <= GIU_IRQ_LAST; i++) {
692 if (i < GIU_IRQ(GIUINT_HIGH_OFFSET))
693 irq_desc[i].chip = &giuint_low_irq_type;
694 else
695 irq_desc[i].chip = &giuint_high_irq_type;
698 return cascade_irq(GIUINT_IRQ, giu_get_irq);
701 static int __devexit giu_remove(struct platform_device *dev)
703 iounmap(giu_base);
705 release_resource(giu_resource1);
706 if (giu_flags & GPIO_HAS_PULLUPDOWN_IO)
707 release_resource(giu_resource2);
709 return 0;
712 static struct platform_device *giu_platform_device;
714 static struct platform_driver giu_device_driver = {
715 .probe = giu_probe,
716 .remove = __devexit_p(giu_remove),
717 .driver = {
718 .name = "GIU",
719 .owner = THIS_MODULE,
723 static int __init vr41xx_giu_init(void)
725 int retval;
727 giu_platform_device = platform_device_alloc("GIU", -1);
728 if (!giu_platform_device)
729 return -ENOMEM;
731 retval = platform_device_add(giu_platform_device);
732 if (retval < 0) {
733 platform_device_put(giu_platform_device);
734 return retval;
737 retval = platform_driver_register(&giu_device_driver);
738 if (retval < 0)
739 platform_device_unregister(giu_platform_device);
741 return retval;
744 static void __exit vr41xx_giu_exit(void)
746 platform_driver_unregister(&giu_device_driver);
748 platform_device_unregister(giu_platform_device);
751 module_init(vr41xx_giu_init);
752 module_exit(vr41xx_giu_exit);