kernel-ark/drivers/char/vr41xx_giu.c
Arjan van de Ven 62322d2554 [PATCH] make more file_operation structs static
Mark the static struct file_operations in drivers/char as const.  Making
them const prevents accidental bugs, and moves them to the .rodata section
so that they no longer do any false sharing; in addition with the proper
debug option they are then protected against corruption..

[akpm@osdl.org: build fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:26:59 -07:00

752 lines
16 KiB
C

/*
* Driver for NEC VR4100 series General-purpose I/O Unit.
*
* Copyright (C) 2002 MontaVista Software Inc.
* Author: Yoichi Yuasa <yyuasa@mvista.com or source@mvista.com>
* Copyright (C) 2003-2005 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/platform_device.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <asm/cpu.h>
#include <asm/io.h>
#include <asm/vr41xx/giu.h>
#include <asm/vr41xx/vr41xx.h>
MODULE_AUTHOR("Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>");
MODULE_DESCRIPTION("NEC VR4100 series General-purpose I/O Unit driver");
MODULE_LICENSE("GPL");
static int major; /* default is dynamic major device number */
module_param(major, int, 0);
MODULE_PARM_DESC(major, "Major device number");
#define GIU_TYPE1_START 0x0b000100UL
#define GIU_TYPE1_SIZE 0x20UL
#define GIU_TYPE2_START 0x0f000140UL
#define GIU_TYPE2_SIZE 0x20UL
#define GIU_TYPE3_START 0x0f000140UL
#define GIU_TYPE3_SIZE 0x28UL
#define GIU_PULLUPDOWN_START 0x0b0002e0UL
#define GIU_PULLUPDOWN_SIZE 0x04UL
#define GIUIOSELL 0x00
#define GIUIOSELH 0x02
#define GIUPIODL 0x04
#define GIUPIODH 0x06
#define GIUINTSTATL 0x08
#define GIUINTSTATH 0x0a
#define GIUINTENL 0x0c
#define GIUINTENH 0x0e
#define GIUINTTYPL 0x10
#define GIUINTTYPH 0x12
#define GIUINTALSELL 0x14
#define GIUINTALSELH 0x16
#define GIUINTHTSELL 0x18
#define GIUINTHTSELH 0x1a
#define GIUPODATL 0x1c
#define GIUPODATEN 0x1c
#define GIUPODATH 0x1e
#define PIOEN0 0x0100
#define PIOEN1 0x0200
#define GIUPODAT 0x1e
#define GIUFEDGEINHL 0x20
#define GIUFEDGEINHH 0x22
#define GIUREDGEINHL 0x24
#define GIUREDGEINHH 0x26
#define GIUUSEUPDN 0x1e0
#define GIUTERMUPDN 0x1e2
#define GPIO_HAS_PULLUPDOWN_IO 0x0001
#define GPIO_HAS_OUTPUT_ENABLE 0x0002
#define GPIO_HAS_INTERRUPT_EDGE_SELECT 0x0100
static spinlock_t giu_lock;
static struct resource *giu_resource1;
static struct resource *giu_resource2;
static unsigned long giu_flags;
static unsigned int giu_nr_pins;
static void __iomem *giu_base;
#define giu_read(offset) readw(giu_base + (offset))
#define giu_write(offset, value) writew((value), giu_base + (offset))
#define GPIO_PIN_OF_IRQ(irq) ((irq) - GIU_IRQ_BASE)
#define GIUINT_HIGH_OFFSET 16
#define GIUINT_HIGH_MAX 32
static inline uint16_t giu_set(uint16_t offset, uint16_t set)
{
uint16_t data;
data = giu_read(offset);
data |= set;
giu_write(offset, data);
return data;
}
static inline uint16_t giu_clear(uint16_t offset, uint16_t clear)
{
uint16_t data;
data = giu_read(offset);
data &= ~clear;
giu_write(offset, data);
return data;
}
static unsigned int startup_giuint_low_irq(unsigned int irq)
{
unsigned int pin;
pin = GPIO_PIN_OF_IRQ(irq);
giu_write(GIUINTSTATL, 1 << pin);
giu_set(GIUINTENL, 1 << pin);
return 0;
}
static void shutdown_giuint_low_irq(unsigned int irq)
{
giu_clear(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
}
static void enable_giuint_low_irq(unsigned int irq)
{
giu_set(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
}
#define disable_giuint_low_irq shutdown_giuint_low_irq
static void ack_giuint_low_irq(unsigned int irq)
{
unsigned int pin;
pin = GPIO_PIN_OF_IRQ(irq);
giu_clear(GIUINTENL, 1 << pin);
giu_write(GIUINTSTATL, 1 << pin);
}
static void end_giuint_low_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
giu_set(GIUINTENL, 1 << GPIO_PIN_OF_IRQ(irq));
}
static struct hw_interrupt_type giuint_low_irq_type = {
.typename = "GIUINTL",
.startup = startup_giuint_low_irq,
.shutdown = shutdown_giuint_low_irq,
.enable = enable_giuint_low_irq,
.disable = disable_giuint_low_irq,
.ack = ack_giuint_low_irq,
.end = end_giuint_low_irq,
};
static unsigned int startup_giuint_high_irq(unsigned int irq)
{
unsigned int pin;
pin = GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET;
giu_write(GIUINTSTATH, 1 << pin);
giu_set(GIUINTENH, 1 << pin);
return 0;
}
static void shutdown_giuint_high_irq(unsigned int irq)
{
giu_clear(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
}
static void enable_giuint_high_irq(unsigned int irq)
{
giu_set(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
}
#define disable_giuint_high_irq shutdown_giuint_high_irq
static void ack_giuint_high_irq(unsigned int irq)
{
unsigned int pin;
pin = GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET;
giu_clear(GIUINTENH, 1 << pin);
giu_write(GIUINTSTATH, 1 << pin);
}
static void end_giuint_high_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
giu_set(GIUINTENH, 1 << (GPIO_PIN_OF_IRQ(irq) - GIUINT_HIGH_OFFSET));
}
static struct hw_interrupt_type giuint_high_irq_type = {
.typename = "GIUINTH",
.startup = startup_giuint_high_irq,
.shutdown = shutdown_giuint_high_irq,
.enable = enable_giuint_high_irq,
.disable = disable_giuint_high_irq,
.ack = ack_giuint_high_irq,
.end = end_giuint_high_irq,
};
static int giu_get_irq(unsigned int irq, struct pt_regs *regs)
{
uint16_t pendl, pendh, maskl, maskh;
int i;
pendl = giu_read(GIUINTSTATL);
pendh = giu_read(GIUINTSTATH);
maskl = giu_read(GIUINTENL);
maskh = giu_read(GIUINTENH);
maskl &= pendl;
maskh &= pendh;
if (maskl) {
for (i = 0; i < 16; i++) {
if (maskl & (1 << i))
return GIU_IRQ(i);
}
} else if (maskh) {
for (i = 0; i < 16; i++) {
if (maskh & (1 << i))
return GIU_IRQ(i + GIUINT_HIGH_OFFSET);
}
}
printk(KERN_ERR "spurious GIU interrupt: %04x(%04x),%04x(%04x)\n",
maskl, pendl, maskh, pendh);
atomic_inc(&irq_err_count);
return -EINVAL;
}
void vr41xx_set_irq_trigger(unsigned int pin, irq_trigger_t trigger, irq_signal_t signal)
{
uint16_t mask;
if (pin < GIUINT_HIGH_OFFSET) {
mask = 1 << pin;
if (trigger != IRQ_TRIGGER_LEVEL) {
giu_set(GIUINTTYPL, mask);
if (signal == IRQ_SIGNAL_HOLD)
giu_set(GIUINTHTSELL, mask);
else
giu_clear(GIUINTHTSELL, mask);
if (current_cpu_data.cputype == CPU_VR4133) {
switch (trigger) {
case IRQ_TRIGGER_EDGE_FALLING:
giu_set(GIUFEDGEINHL, mask);
giu_clear(GIUREDGEINHL, mask);
break;
case IRQ_TRIGGER_EDGE_RISING:
giu_clear(GIUFEDGEINHL, mask);
giu_set(GIUREDGEINHL, mask);
break;
default:
giu_set(GIUFEDGEINHL, mask);
giu_set(GIUREDGEINHL, mask);
break;
}
}
} else {
giu_clear(GIUINTTYPL, mask);
giu_clear(GIUINTHTSELL, mask);
}
giu_write(GIUINTSTATL, mask);
} else if (pin < GIUINT_HIGH_MAX) {
mask = 1 << (pin - GIUINT_HIGH_OFFSET);
if (trigger != IRQ_TRIGGER_LEVEL) {
giu_set(GIUINTTYPH, mask);
if (signal == IRQ_SIGNAL_HOLD)
giu_set(GIUINTHTSELH, mask);
else
giu_clear(GIUINTHTSELH, mask);
if (current_cpu_data.cputype == CPU_VR4133) {
switch (trigger) {
case IRQ_TRIGGER_EDGE_FALLING:
giu_set(GIUFEDGEINHH, mask);
giu_clear(GIUREDGEINHH, mask);
break;
case IRQ_TRIGGER_EDGE_RISING:
giu_clear(GIUFEDGEINHH, mask);
giu_set(GIUREDGEINHH, mask);
break;
default:
giu_set(GIUFEDGEINHH, mask);
giu_set(GIUREDGEINHH, mask);
break;
}
}
} else {
giu_clear(GIUINTTYPH, mask);
giu_clear(GIUINTHTSELH, mask);
}
giu_write(GIUINTSTATH, mask);
}
}
EXPORT_SYMBOL_GPL(vr41xx_set_irq_trigger);
void vr41xx_set_irq_level(unsigned int pin, irq_level_t level)
{
uint16_t mask;
if (pin < GIUINT_HIGH_OFFSET) {
mask = 1 << pin;
if (level == IRQ_LEVEL_HIGH)
giu_set(GIUINTALSELL, mask);
else
giu_clear(GIUINTALSELL, mask);
giu_write(GIUINTSTATL, mask);
} else if (pin < GIUINT_HIGH_MAX) {
mask = 1 << (pin - GIUINT_HIGH_OFFSET);
if (level == IRQ_LEVEL_HIGH)
giu_set(GIUINTALSELH, mask);
else
giu_clear(GIUINTALSELH, mask);
giu_write(GIUINTSTATH, mask);
}
}
EXPORT_SYMBOL_GPL(vr41xx_set_irq_level);
gpio_data_t vr41xx_gpio_get_pin(unsigned int pin)
{
uint16_t reg, mask;
if (pin >= giu_nr_pins)
return GPIO_DATA_INVAL;
if (pin < 16) {
reg = giu_read(GIUPIODL);
mask = (uint16_t)1 << pin;
} else if (pin < 32) {
reg = giu_read(GIUPIODH);
mask = (uint16_t)1 << (pin - 16);
} else if (pin < 48) {
reg = giu_read(GIUPODATL);
mask = (uint16_t)1 << (pin - 32);
} else {
reg = giu_read(GIUPODATH);
mask = (uint16_t)1 << (pin - 48);
}
if (reg & mask)
return GPIO_DATA_HIGH;
return GPIO_DATA_LOW;
}
EXPORT_SYMBOL_GPL(vr41xx_gpio_get_pin);
int vr41xx_gpio_set_pin(unsigned int pin, gpio_data_t data)
{
uint16_t offset, mask, reg;
unsigned long flags;
if (pin >= giu_nr_pins)
return -EINVAL;
if (pin < 16) {
offset = GIUPIODL;
mask = (uint16_t)1 << pin;
} else if (pin < 32) {
offset = GIUPIODH;
mask = (uint16_t)1 << (pin - 16);
} else if (pin < 48) {
offset = GIUPODATL;
mask = (uint16_t)1 << (pin - 32);
} else {
offset = GIUPODATH;
mask = (uint16_t)1 << (pin - 48);
}
spin_lock_irqsave(&giu_lock, flags);
reg = giu_read(offset);
if (data == GPIO_DATA_HIGH)
reg |= mask;
else
reg &= ~mask;
giu_write(offset, reg);
spin_unlock_irqrestore(&giu_lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(vr41xx_gpio_set_pin);
int vr41xx_gpio_set_direction(unsigned int pin, gpio_direction_t dir)
{
uint16_t offset, mask, reg;
unsigned long flags;
if (pin >= giu_nr_pins)
return -EINVAL;
if (pin < 16) {
offset = GIUIOSELL;
mask = (uint16_t)1 << pin;
} else if (pin < 32) {
offset = GIUIOSELH;
mask = (uint16_t)1 << (pin - 16);
} else {
if (giu_flags & GPIO_HAS_OUTPUT_ENABLE) {
offset = GIUPODATEN;
mask = (uint16_t)1 << (pin - 32);
} else {
switch (pin) {
case 48:
offset = GIUPODATH;
mask = PIOEN0;
break;
case 49:
offset = GIUPODATH;
mask = PIOEN1;
break;
default:
return -EINVAL;
}
}
}
spin_lock_irqsave(&giu_lock, flags);
reg = giu_read(offset);
if (dir == GPIO_OUTPUT)
reg |= mask;
else
reg &= ~mask;
giu_write(offset, reg);
spin_unlock_irqrestore(&giu_lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(vr41xx_gpio_set_direction);
int vr41xx_gpio_pullupdown(unsigned int pin, gpio_pull_t pull)
{
uint16_t reg, mask;
unsigned long flags;
if ((giu_flags & GPIO_HAS_PULLUPDOWN_IO) != GPIO_HAS_PULLUPDOWN_IO)
return -EPERM;
if (pin >= 15)
return -EINVAL;
mask = (uint16_t)1 << pin;
spin_lock_irqsave(&giu_lock, flags);
if (pull == GPIO_PULL_UP || pull == GPIO_PULL_DOWN) {
reg = giu_read(GIUTERMUPDN);
if (pull == GPIO_PULL_UP)
reg |= mask;
else
reg &= ~mask;
giu_write(GIUTERMUPDN, reg);
reg = giu_read(GIUUSEUPDN);
reg |= mask;
giu_write(GIUUSEUPDN, reg);
} else {
reg = giu_read(GIUUSEUPDN);
reg &= ~mask;
giu_write(GIUUSEUPDN, reg);
}
spin_unlock_irqrestore(&giu_lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(vr41xx_gpio_pullupdown);
static ssize_t gpio_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
unsigned int pin;
char value = '0';
pin = iminor(file->f_dentry->d_inode);
if (pin >= giu_nr_pins)
return -EBADF;
if (vr41xx_gpio_get_pin(pin) == GPIO_DATA_HIGH)
value = '1';
if (len <= 0)
return -EFAULT;
if (put_user(value, buf))
return -EFAULT;
return 1;
}
static ssize_t gpio_write(struct file *file, const char __user *data,
size_t len, loff_t *ppos)
{
unsigned int pin;
size_t i;
char c;
int retval = 0;
pin = iminor(file->f_dentry->d_inode);
if (pin >= giu_nr_pins)
return -EBADF;
for (i = 0; i < len; i++) {
if (get_user(c, data + i))
return -EFAULT;
switch (c) {
case '0':
retval = vr41xx_gpio_set_pin(pin, GPIO_DATA_LOW);
break;
case '1':
retval = vr41xx_gpio_set_pin(pin, GPIO_DATA_HIGH);
break;
case 'D':
printk(KERN_INFO "GPIO%d: pull down\n", pin);
retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DOWN);
break;
case 'd':
printk(KERN_INFO "GPIO%d: pull up/down disable\n", pin);
retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DISABLE);
break;
case 'I':
printk(KERN_INFO "GPIO%d: input\n", pin);
retval = vr41xx_gpio_set_direction(pin, GPIO_INPUT);
break;
case 'O':
printk(KERN_INFO "GPIO%d: output\n", pin);
retval = vr41xx_gpio_set_direction(pin, GPIO_OUTPUT);
break;
case 'o':
printk(KERN_INFO "GPIO%d: output disable\n", pin);
retval = vr41xx_gpio_set_direction(pin, GPIO_OUTPUT_DISABLE);
break;
case 'P':
printk(KERN_INFO "GPIO%d: pull up\n", pin);
retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_UP);
break;
case 'p':
printk(KERN_INFO "GPIO%d: pull up/down disable\n", pin);
retval = vr41xx_gpio_pullupdown(pin, GPIO_PULL_DISABLE);
break;
default:
break;
}
if (retval < 0)
break;
}
return i;
}
static int gpio_open(struct inode *inode, struct file *file)
{
unsigned int pin;
pin = iminor(inode);
if (pin >= giu_nr_pins)
return -EBADF;
return nonseekable_open(inode, file);
}
static int gpio_release(struct inode *inode, struct file *file)
{
unsigned int pin;
pin = iminor(inode);
if (pin >= giu_nr_pins)
return -EBADF;
return 0;
}
static const struct file_operations gpio_fops = {
.owner = THIS_MODULE,
.read = gpio_read,
.write = gpio_write,
.open = gpio_open,
.release = gpio_release,
};
static int __devinit giu_probe(struct platform_device *dev)
{
unsigned long start, size, flags = 0;
unsigned int nr_pins = 0;
struct resource *res1, *res2 = NULL;
void *base;
int retval, i;
switch (current_cpu_data.cputype) {
case CPU_VR4111:
case CPU_VR4121:
start = GIU_TYPE1_START;
size = GIU_TYPE1_SIZE;
flags = GPIO_HAS_PULLUPDOWN_IO;
nr_pins = 50;
break;
case CPU_VR4122:
case CPU_VR4131:
start = GIU_TYPE2_START;
size = GIU_TYPE2_SIZE;
nr_pins = 36;
break;
case CPU_VR4133:
start = GIU_TYPE3_START;
size = GIU_TYPE3_SIZE;
flags = GPIO_HAS_INTERRUPT_EDGE_SELECT;
nr_pins = 48;
break;
default:
return -ENODEV;
}
res1 = request_mem_region(start, size, "GIU");
if (res1 == NULL)
return -EBUSY;
base = ioremap(start, size);
if (base == NULL) {
release_resource(res1);
return -ENOMEM;
}
if (flags & GPIO_HAS_PULLUPDOWN_IO) {
res2 = request_mem_region(GIU_PULLUPDOWN_START, GIU_PULLUPDOWN_SIZE, "GIU");
if (res2 == NULL) {
iounmap(base);
release_resource(res1);
return -EBUSY;
}
}
retval = register_chrdev(major, "GIU", &gpio_fops);
if (retval < 0) {
iounmap(base);
release_resource(res1);
release_resource(res2);
return retval;
}
if (major == 0) {
major = retval;
printk(KERN_INFO "GIU: major number %d\n", major);
}
spin_lock_init(&giu_lock);
giu_base = base;
giu_resource1 = res1;
giu_resource2 = res2;
giu_flags = flags;
giu_nr_pins = nr_pins;
giu_write(GIUINTENL, 0);
giu_write(GIUINTENH, 0);
for (i = GIU_IRQ_BASE; i <= GIU_IRQ_LAST; i++) {
if (i < GIU_IRQ(GIUINT_HIGH_OFFSET))
irq_desc[i].chip = &giuint_low_irq_type;
else
irq_desc[i].chip = &giuint_high_irq_type;
}
return cascade_irq(GIUINT_IRQ, giu_get_irq);
}
static int __devexit giu_remove(struct platform_device *dev)
{
iounmap(giu_base);
release_resource(giu_resource1);
if (giu_flags & GPIO_HAS_PULLUPDOWN_IO)
release_resource(giu_resource2);
return 0;
}
static struct platform_device *giu_platform_device;
static struct platform_driver giu_device_driver = {
.probe = giu_probe,
.remove = __devexit_p(giu_remove),
.driver = {
.name = "GIU",
.owner = THIS_MODULE,
},
};
static int __init vr41xx_giu_init(void)
{
int retval;
giu_platform_device = platform_device_alloc("GIU", -1);
if (!giu_platform_device)
return -ENOMEM;
retval = platform_device_add(giu_platform_device);
if (retval < 0) {
platform_device_put(giu_platform_device);
return retval;
}
retval = platform_driver_register(&giu_device_driver);
if (retval < 0)
platform_device_unregister(giu_platform_device);
return retval;
}
static void __exit vr41xx_giu_exit(void)
{
platform_driver_unregister(&giu_device_driver);
platform_device_unregister(giu_platform_device);
}
module_init(vr41xx_giu_init);
module_exit(vr41xx_giu_exit);