android_kernel_cmhtcleo/arch/cris/arch-v10/drivers/gpio.c

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2010-08-27 09:19:57 +00:00
/*
* Etrax general port I/O device
*
* Copyright (c) 1999-2007 Axis Communications AB
*
* Authors: Bjorn Wesen (initial version)
* Ola Knutsson (LED handling)
* Johan Adolfsson (read/set directions, write, port G)
*/
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/smp_lock.h>
#include <linux/string.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <asm/etraxgpio.h>
#include <arch/svinto.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/irq.h>
#include <arch/io_interface_mux.h>
#define GPIO_MAJOR 120 /* experimental MAJOR number */
#define D(x)
#if 0
static int dp_cnt;
#define DP(x) do { dp_cnt++; if (dp_cnt % 1000 == 0) x; }while(0)
#else
#define DP(x)
#endif
static char gpio_name[] = "etrax gpio";
#if 0
static wait_queue_head_t *gpio_wq;
#endif
static int gpio_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg);
static ssize_t gpio_write(struct file *file, const char __user *buf,
size_t count, loff_t *off);
static int gpio_open(struct inode *inode, struct file *filp);
static int gpio_release(struct inode *inode, struct file *filp);
static unsigned int gpio_poll(struct file *filp, struct poll_table_struct *wait);
/* private data per open() of this driver */
struct gpio_private {
struct gpio_private *next;
/* These fields are for PA and PB only */
volatile unsigned char *port, *shadow;
volatile unsigned char *dir, *dir_shadow;
unsigned char changeable_dir;
unsigned char changeable_bits;
unsigned char clk_mask;
unsigned char data_mask;
unsigned char write_msb;
unsigned char pad1, pad2, pad3;
/* These fields are generic */
unsigned long highalarm, lowalarm;
wait_queue_head_t alarm_wq;
int minor;
};
/* linked list of alarms to check for */
static struct gpio_private *alarmlist;
static int gpio_some_alarms; /* Set if someone uses alarm */
static unsigned long gpio_pa_irq_enabled_mask;
static DEFINE_SPINLOCK(gpio_lock); /* Protect directions etc */
/* Port A and B use 8 bit access, but Port G is 32 bit */
#define NUM_PORTS (GPIO_MINOR_B+1)
static volatile unsigned char *ports[NUM_PORTS] = {
R_PORT_PA_DATA,
R_PORT_PB_DATA,
};
static volatile unsigned char *shads[NUM_PORTS] = {
&port_pa_data_shadow,
&port_pb_data_shadow
};
/* What direction bits that are user changeable 1=changeable*/
#ifndef CONFIG_ETRAX_PA_CHANGEABLE_DIR
#define CONFIG_ETRAX_PA_CHANGEABLE_DIR 0x00
#endif
#ifndef CONFIG_ETRAX_PB_CHANGEABLE_DIR
#define CONFIG_ETRAX_PB_CHANGEABLE_DIR 0x00
#endif
#ifndef CONFIG_ETRAX_PA_CHANGEABLE_BITS
#define CONFIG_ETRAX_PA_CHANGEABLE_BITS 0xFF
#endif
#ifndef CONFIG_ETRAX_PB_CHANGEABLE_BITS
#define CONFIG_ETRAX_PB_CHANGEABLE_BITS 0xFF
#endif
static unsigned char changeable_dir[NUM_PORTS] = {
CONFIG_ETRAX_PA_CHANGEABLE_DIR,
CONFIG_ETRAX_PB_CHANGEABLE_DIR
};
static unsigned char changeable_bits[NUM_PORTS] = {
CONFIG_ETRAX_PA_CHANGEABLE_BITS,
CONFIG_ETRAX_PB_CHANGEABLE_BITS
};
static volatile unsigned char *dir[NUM_PORTS] = {
R_PORT_PA_DIR,
R_PORT_PB_DIR
};
static volatile unsigned char *dir_shadow[NUM_PORTS] = {
&port_pa_dir_shadow,
&port_pb_dir_shadow
};
/* All bits in port g that can change dir. */
static const unsigned long int changeable_dir_g_mask = 0x01FFFF01;
/* Port G is 32 bit, handle it special, some bits are both inputs
and outputs at the same time, only some of the bits can change direction
and some of them in groups of 8 bit. */
static unsigned long changeable_dir_g;
static unsigned long dir_g_in_bits;
static unsigned long dir_g_out_bits;
static unsigned long dir_g_shadow; /* 1=output */
#define USE_PORTS(priv) ((priv)->minor <= GPIO_MINOR_B)
static unsigned int gpio_poll(struct file *file, poll_table *wait)
{
unsigned int mask = 0;
struct gpio_private *priv = file->private_data;
unsigned long data;
unsigned long flags;
spin_lock_irqsave(&gpio_lock, flags);
poll_wait(file, &priv->alarm_wq, wait);
if (priv->minor == GPIO_MINOR_A) {
unsigned long tmp;
data = *R_PORT_PA_DATA;
/* PA has support for high level interrupt -
* lets activate for those low and with highalarm set
*/
tmp = ~data & priv->highalarm & 0xFF;
tmp = (tmp << R_IRQ_MASK1_SET__pa0__BITNR);
gpio_pa_irq_enabled_mask |= tmp;
*R_IRQ_MASK1_SET = tmp;
} else if (priv->minor == GPIO_MINOR_B)
data = *R_PORT_PB_DATA;
else if (priv->minor == GPIO_MINOR_G)
data = *R_PORT_G_DATA;
else {
mask = 0;
goto out;
}
if ((data & priv->highalarm) ||
(~data & priv->lowalarm)) {
mask = POLLIN|POLLRDNORM;
}
out:
spin_unlock_irqrestore(&gpio_lock, flags);
DP(printk("gpio_poll ready: mask 0x%08X\n", mask));
return mask;
}
int etrax_gpio_wake_up_check(void)
{
struct gpio_private *priv;
unsigned long data = 0;
int ret = 0;
unsigned long flags;
spin_lock_irqsave(&gpio_lock, flags);
priv = alarmlist;
while (priv) {
if (USE_PORTS(priv))
data = *priv->port;
else if (priv->minor == GPIO_MINOR_G)
data = *R_PORT_G_DATA;
if ((data & priv->highalarm) ||
(~data & priv->lowalarm)) {
DP(printk("etrax_gpio_wake_up_check %i\n",priv->minor));
wake_up_interruptible(&priv->alarm_wq);
ret = 1;
}
priv = priv->next;
}
spin_unlock_irqrestore(&gpio_lock, flags);
return ret;
}
static irqreturn_t
gpio_poll_timer_interrupt(int irq, void *dev_id)
{
if (gpio_some_alarms) {
etrax_gpio_wake_up_check();
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static irqreturn_t
gpio_interrupt(int irq, void *dev_id)
{
unsigned long tmp;
unsigned long flags;
spin_lock_irqsave(&gpio_lock, flags);
/* Find what PA interrupts are active */
tmp = (*R_IRQ_READ1);
/* Find those that we have enabled */
tmp &= gpio_pa_irq_enabled_mask;
/* Clear them.. */
*R_IRQ_MASK1_CLR = tmp;
gpio_pa_irq_enabled_mask &= ~tmp;
spin_unlock_irqrestore(&gpio_lock, flags);
if (gpio_some_alarms)
return IRQ_RETVAL(etrax_gpio_wake_up_check());
return IRQ_NONE;
}
static void gpio_write_bit(struct gpio_private *priv,
unsigned char data, int bit)
{
*priv->port = *priv->shadow &= ~(priv->clk_mask);
if (data & 1 << bit)
*priv->port = *priv->shadow |= priv->data_mask;
else
*priv->port = *priv->shadow &= ~(priv->data_mask);
/* For FPGA: min 5.0ns (DCC) before CCLK high */
*priv->port = *priv->shadow |= priv->clk_mask;
}
static void gpio_write_byte(struct gpio_private *priv, unsigned char data)
{
int i;
if (priv->write_msb)
for (i = 7; i >= 0; i--)
gpio_write_bit(priv, data, i);
else
for (i = 0; i <= 7; i++)
gpio_write_bit(priv, data, i);
}
static ssize_t gpio_write(struct file *file, const char __user *buf,
size_t count, loff_t *off)
{
struct gpio_private *priv = file->private_data;
unsigned long flags;
ssize_t retval = count;
if (priv->minor != GPIO_MINOR_A && priv->minor != GPIO_MINOR_B)
return -EFAULT;
if (!access_ok(VERIFY_READ, buf, count))
return -EFAULT;
spin_lock_irqsave(&gpio_lock, flags);
/* It must have been configured using the IO_CFG_WRITE_MODE */
/* Perhaps a better error code? */
if (priv->clk_mask == 0 || priv->data_mask == 0) {
retval = -EPERM;
goto out;
}
D(printk(KERN_DEBUG "gpio_write: %02X to data 0x%02X "
"clk 0x%02X msb: %i\n",
count, priv->data_mask, priv->clk_mask, priv->write_msb));
while (count--)
gpio_write_byte(priv, *buf++);
out:
spin_unlock_irqrestore(&gpio_lock, flags);
return retval;
}
static int
gpio_open(struct inode *inode, struct file *filp)
{
struct gpio_private *priv;
int p = iminor(inode);
unsigned long flags;
if (p > GPIO_MINOR_LAST)
return -EINVAL;
priv = kzalloc(sizeof(struct gpio_private), GFP_KERNEL);
if (!priv)
return -ENOMEM;
lock_kernel();
priv->minor = p;
/* initialize the io/alarm struct */
if (USE_PORTS(priv)) { /* A and B */
priv->port = ports[p];
priv->shadow = shads[p];
priv->dir = dir[p];
priv->dir_shadow = dir_shadow[p];
priv->changeable_dir = changeable_dir[p];
priv->changeable_bits = changeable_bits[p];
} else {
priv->port = NULL;
priv->shadow = NULL;
priv->dir = NULL;
priv->dir_shadow = NULL;
priv->changeable_dir = 0;
priv->changeable_bits = 0;
}
priv->highalarm = 0;
priv->lowalarm = 0;
priv->clk_mask = 0;
priv->data_mask = 0;
init_waitqueue_head(&priv->alarm_wq);
filp->private_data = priv;
/* link it into our alarmlist */
spin_lock_irqsave(&gpio_lock, flags);
priv->next = alarmlist;
alarmlist = priv;
spin_unlock_irqrestore(&gpio_lock, flags);
unlock_kernel();
return 0;
}
static int
gpio_release(struct inode *inode, struct file *filp)
{
struct gpio_private *p;
struct gpio_private *todel;
unsigned long flags;
spin_lock_irqsave(&gpio_lock, flags);
p = alarmlist;
todel = filp->private_data;
/* unlink from alarmlist and free the private structure */
if (p == todel) {
alarmlist = todel->next;
} else {
while (p->next != todel)
p = p->next;
p->next = todel->next;
}
kfree(todel);
/* Check if there are still any alarms set */
p = alarmlist;
while (p) {
if (p->highalarm | p->lowalarm) {
gpio_some_alarms = 1;
goto out;
}
p = p->next;
}
gpio_some_alarms = 0;
out:
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
/* Main device API. ioctl's to read/set/clear bits, as well as to
* set alarms to wait for using a subsequent select().
*/
unsigned long inline setget_input(struct gpio_private *priv, unsigned long arg)
{
/* Set direction 0=unchanged 1=input,
* return mask with 1=input */
if (USE_PORTS(priv)) {
*priv->dir = *priv->dir_shadow &=
~((unsigned char)arg & priv->changeable_dir);
return ~(*priv->dir_shadow) & 0xFF; /* Only 8 bits */
}
if (priv->minor != GPIO_MINOR_G)
return 0;
/* We must fiddle with R_GEN_CONFIG to change dir */
if (((arg & dir_g_in_bits) != arg) &&
(arg & changeable_dir_g)) {
arg &= changeable_dir_g;
/* Clear bits in genconfig to set to input */
if (arg & (1<<0)) {
genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, g0dir);
dir_g_in_bits |= (1<<0);
dir_g_out_bits &= ~(1<<0);
}
if ((arg & 0x0000FF00) == 0x0000FF00) {
genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, g8_15dir);
dir_g_in_bits |= 0x0000FF00;
dir_g_out_bits &= ~0x0000FF00;
}
if ((arg & 0x00FF0000) == 0x00FF0000) {
genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, g16_23dir);
dir_g_in_bits |= 0x00FF0000;
dir_g_out_bits &= ~0x00FF0000;
}
if (arg & (1<<24)) {
genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, g24dir);
dir_g_in_bits |= (1<<24);
dir_g_out_bits &= ~(1<<24);
}
D(printk(KERN_DEBUG "gpio: SETINPUT on port G set "
"genconfig to 0x%08lX "
"in_bits: 0x%08lX "
"out_bits: 0x%08lX\n",
(unsigned long)genconfig_shadow,
dir_g_in_bits, dir_g_out_bits));
*R_GEN_CONFIG = genconfig_shadow;
/* Must be a >120 ns delay before writing this again */
}
return dir_g_in_bits;
} /* setget_input */
unsigned long inline setget_output(struct gpio_private *priv, unsigned long arg)
{
if (USE_PORTS(priv)) {
*priv->dir = *priv->dir_shadow |=
((unsigned char)arg & priv->changeable_dir);
return *priv->dir_shadow;
}
if (priv->minor != GPIO_MINOR_G)
return 0;
/* We must fiddle with R_GEN_CONFIG to change dir */
if (((arg & dir_g_out_bits) != arg) &&
(arg & changeable_dir_g)) {
/* Set bits in genconfig to set to output */
if (arg & (1<<0)) {
genconfig_shadow |= IO_MASK(R_GEN_CONFIG, g0dir);
dir_g_out_bits |= (1<<0);
dir_g_in_bits &= ~(1<<0);
}
if ((arg & 0x0000FF00) == 0x0000FF00) {
genconfig_shadow |= IO_MASK(R_GEN_CONFIG, g8_15dir);
dir_g_out_bits |= 0x0000FF00;
dir_g_in_bits &= ~0x0000FF00;
}
if ((arg & 0x00FF0000) == 0x00FF0000) {
genconfig_shadow |= IO_MASK(R_GEN_CONFIG, g16_23dir);
dir_g_out_bits |= 0x00FF0000;
dir_g_in_bits &= ~0x00FF0000;
}
if (arg & (1<<24)) {
genconfig_shadow |= IO_MASK(R_GEN_CONFIG, g24dir);
dir_g_out_bits |= (1<<24);
dir_g_in_bits &= ~(1<<24);
}
D(printk(KERN_INFO "gpio: SETOUTPUT on port G set "
"genconfig to 0x%08lX "
"in_bits: 0x%08lX "
"out_bits: 0x%08lX\n",
(unsigned long)genconfig_shadow,
dir_g_in_bits, dir_g_out_bits));
*R_GEN_CONFIG = genconfig_shadow;
/* Must be a >120 ns delay before writing this again */
}
return dir_g_out_bits & 0x7FFFFFFF;
} /* setget_output */
static int
gpio_leds_ioctl(unsigned int cmd, unsigned long arg);
static int
gpio_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
unsigned long flags;
unsigned long val;
int ret = 0;
struct gpio_private *priv = file->private_data;
if (_IOC_TYPE(cmd) != ETRAXGPIO_IOCTYPE)
return -EINVAL;
spin_lock_irqsave(&gpio_lock, flags);
switch (_IOC_NR(cmd)) {
case IO_READBITS: /* Use IO_READ_INBITS and IO_READ_OUTBITS instead */
// read the port
if (USE_PORTS(priv)) {
ret = *priv->port;
} else if (priv->minor == GPIO_MINOR_G) {
ret = (*R_PORT_G_DATA) & 0x7FFFFFFF;
}
break;
case IO_SETBITS:
// set changeable bits with a 1 in arg
if (USE_PORTS(priv)) {
*priv->port = *priv->shadow |=
((unsigned char)arg & priv->changeable_bits);
} else if (priv->minor == GPIO_MINOR_G) {
*R_PORT_G_DATA = port_g_data_shadow |= (arg & dir_g_out_bits);
}
break;
case IO_CLRBITS:
// clear changeable bits with a 1 in arg
if (USE_PORTS(priv)) {
*priv->port = *priv->shadow &=
~((unsigned char)arg & priv->changeable_bits);
} else if (priv->minor == GPIO_MINOR_G) {
*R_PORT_G_DATA = port_g_data_shadow &= ~((unsigned long)arg & dir_g_out_bits);
}
break;
case IO_HIGHALARM:
// set alarm when bits with 1 in arg go high
priv->highalarm |= arg;
gpio_some_alarms = 1;
break;
case IO_LOWALARM:
// set alarm when bits with 1 in arg go low
priv->lowalarm |= arg;
gpio_some_alarms = 1;
break;
case IO_CLRALARM:
// clear alarm for bits with 1 in arg
priv->highalarm &= ~arg;
priv->lowalarm &= ~arg;
{
/* Must update gpio_some_alarms */
struct gpio_private *p = alarmlist;
int some_alarms;
spin_lock_irq(&gpio_lock);
p = alarmlist;
some_alarms = 0;
while (p) {
if (p->highalarm | p->lowalarm) {
some_alarms = 1;
break;
}
p = p->next;
}
gpio_some_alarms = some_alarms;
spin_unlock_irq(&gpio_lock);
}
break;
case IO_READDIR: /* Use IO_SETGET_INPUT/OUTPUT instead! */
/* Read direction 0=input 1=output */
if (USE_PORTS(priv)) {
ret = *priv->dir_shadow;
} else if (priv->minor == GPIO_MINOR_G) {
/* Note: Some bits are both in and out,
* Those that are dual is set here as well.
*/
ret = (dir_g_shadow | dir_g_out_bits) & 0x7FFFFFFF;
}
break;
case IO_SETINPUT: /* Use IO_SETGET_INPUT instead! */
/* Set direction 0=unchanged 1=input,
* return mask with 1=input
*/
ret = setget_input(priv, arg) & 0x7FFFFFFF;
break;
case IO_SETOUTPUT: /* Use IO_SETGET_OUTPUT instead! */
/* Set direction 0=unchanged 1=output,
* return mask with 1=output
*/
ret = setget_output(priv, arg) & 0x7FFFFFFF;
break;
case IO_SHUTDOWN:
SOFT_SHUTDOWN();
break;
case IO_GET_PWR_BT:
#if defined (CONFIG_ETRAX_SOFT_SHUTDOWN)
ret = (*R_PORT_G_DATA & ( 1 << CONFIG_ETRAX_POWERBUTTON_BIT));
#else
ret = 0;
#endif
break;
case IO_CFG_WRITE_MODE:
priv->clk_mask = arg & 0xFF;
priv->data_mask = (arg >> 8) & 0xFF;
priv->write_msb = (arg >> 16) & 0x01;
/* Check if we're allowed to change the bits and
* the direction is correct
*/
if (!((priv->clk_mask & priv->changeable_bits) &&
(priv->data_mask & priv->changeable_bits) &&
(priv->clk_mask & *priv->dir_shadow) &&
(priv->data_mask & *priv->dir_shadow)))
{
priv->clk_mask = 0;
priv->data_mask = 0;
ret = -EPERM;
}
break;
case IO_READ_INBITS:
/* *arg is result of reading the input pins */
if (USE_PORTS(priv)) {
val = *priv->port;
} else if (priv->minor == GPIO_MINOR_G) {
val = *R_PORT_G_DATA;
}
if (copy_to_user((void __user *)arg, &val, sizeof(val)))
ret = -EFAULT;
break;
case IO_READ_OUTBITS:
/* *arg is result of reading the output shadow */
if (USE_PORTS(priv)) {
val = *priv->shadow;
} else if (priv->minor == GPIO_MINOR_G) {
val = port_g_data_shadow;
}
if (copy_to_user((void __user *)arg, &val, sizeof(val)))
ret = -EFAULT;
break;
case IO_SETGET_INPUT:
/* bits set in *arg is set to input,
* *arg updated with current input pins.
*/
if (copy_from_user(&val, (void __user *)arg, sizeof(val)))
{
ret = -EFAULT;
break;
}
val = setget_input(priv, val);
if (copy_to_user((void __user *)arg, &val, sizeof(val)))
ret = -EFAULT;
break;
case IO_SETGET_OUTPUT:
/* bits set in *arg is set to output,
* *arg updated with current output pins.
*/
if (copy_from_user(&val, (void __user *)arg, sizeof(val))) {
ret = -EFAULT;
break;
}
val = setget_output(priv, val);
if (copy_to_user((void __user *)arg, &val, sizeof(val)))
ret = -EFAULT;
break;
default:
if (priv->minor == GPIO_MINOR_LEDS)
ret = gpio_leds_ioctl(cmd, arg);
else
ret = -EINVAL;
} /* switch */
spin_unlock_irqrestore(&gpio_lock, flags);
return ret;
}
static int
gpio_leds_ioctl(unsigned int cmd, unsigned long arg)
{
unsigned char green;
unsigned char red;
switch (_IOC_NR(cmd)) {
case IO_LEDACTIVE_SET:
green = ((unsigned char)arg) & 1;
red = (((unsigned char)arg) >> 1) & 1;
CRIS_LED_ACTIVE_SET_G(green);
CRIS_LED_ACTIVE_SET_R(red);
break;
case IO_LED_SETBIT:
CRIS_LED_BIT_SET(arg);
break;
case IO_LED_CLRBIT:
CRIS_LED_BIT_CLR(arg);
break;
default:
return -EINVAL;
} /* switch */
return 0;
}
static const struct file_operations gpio_fops = {
.owner = THIS_MODULE,
.poll = gpio_poll,
.ioctl = gpio_ioctl,
.write = gpio_write,
.open = gpio_open,
.release = gpio_release,
};
static void ioif_watcher(const unsigned int gpio_in_available,
const unsigned int gpio_out_available,
const unsigned char pa_available,
const unsigned char pb_available)
{
unsigned long int flags;
D(printk(KERN_DEBUG "gpio.c: ioif_watcher called\n"));
D(printk(KERN_DEBUG "gpio.c: G in: 0x%08x G out: 0x%08x "
"PA: 0x%02x PB: 0x%02x\n",
gpio_in_available, gpio_out_available,
pa_available, pb_available));
spin_lock_irqsave(&gpio_lock, flags);
dir_g_in_bits = gpio_in_available;
dir_g_out_bits = gpio_out_available;
/* Initialise the dir_g_shadow etc. depending on genconfig */
/* 0=input 1=output */
if (genconfig_shadow & IO_STATE(R_GEN_CONFIG, g0dir, out))
dir_g_shadow |= (1 << 0);
if (genconfig_shadow & IO_STATE(R_GEN_CONFIG, g8_15dir, out))
dir_g_shadow |= 0x0000FF00;
if (genconfig_shadow & IO_STATE(R_GEN_CONFIG, g16_23dir, out))
dir_g_shadow |= 0x00FF0000;
if (genconfig_shadow & IO_STATE(R_GEN_CONFIG, g24dir, out))
dir_g_shadow |= (1 << 24);
changeable_dir_g = changeable_dir_g_mask;
changeable_dir_g &= dir_g_out_bits;
changeable_dir_g &= dir_g_in_bits;
/* Correct the bits that can change direction */
dir_g_out_bits &= ~changeable_dir_g;
dir_g_out_bits |= dir_g_shadow;
dir_g_in_bits &= ~changeable_dir_g;
dir_g_in_bits |= (~dir_g_shadow & changeable_dir_g);
spin_unlock_irqrestore(&gpio_lock, flags);
printk(KERN_INFO "GPIO port G: in_bits: 0x%08lX out_bits: 0x%08lX "
"val: %08lX\n",
dir_g_in_bits, dir_g_out_bits, (unsigned long)*R_PORT_G_DATA);
printk(KERN_INFO "GPIO port G: dir: %08lX changeable: %08lX\n",
dir_g_shadow, changeable_dir_g);
}
/* main driver initialization routine, called from mem.c */
static int __init gpio_init(void)
{
int res;
#if defined (CONFIG_ETRAX_CSP0_LEDS)
int i;
#endif
res = register_chrdev(GPIO_MAJOR, gpio_name, &gpio_fops);
if (res < 0) {
printk(KERN_ERR "gpio: couldn't get a major number.\n");
return res;
}
/* Clear all leds */
#if defined (CONFIG_ETRAX_CSP0_LEDS) || defined (CONFIG_ETRAX_PA_LEDS) || defined (CONFIG_ETRAX_PB_LEDS)
CRIS_LED_NETWORK_SET(0);
CRIS_LED_ACTIVE_SET(0);
CRIS_LED_DISK_READ(0);
CRIS_LED_DISK_WRITE(0);
#if defined (CONFIG_ETRAX_CSP0_LEDS)
for (i = 0; i < 32; i++)
CRIS_LED_BIT_SET(i);
#endif
#endif
/* The I/O interface allocation watcher will be called when
* registering it. */
if (cris_io_interface_register_watcher(ioif_watcher)){
printk(KERN_WARNING "gpio_init: Failed to install IO "
"if allocator watcher\n");
}
printk(KERN_INFO "ETRAX 100LX GPIO driver v2.5, (c) 2001-2008 "
"Axis Communications AB\n");
/* We call etrax_gpio_wake_up_check() from timer interrupt and
* from cpu_idle() in kernel/process.c
* The check in cpu_idle() reduces latency from ~15 ms to ~6 ms
* in some tests.
*/
res = request_irq(TIMER0_IRQ_NBR, gpio_poll_timer_interrupt,
IRQF_SHARED | IRQF_DISABLED, "gpio poll", gpio_name);
if (res) {
printk(KERN_CRIT "err: timer0 irq for gpio\n");
return res;
}
res = request_irq(PA_IRQ_NBR, gpio_interrupt,
IRQF_SHARED | IRQF_DISABLED, "gpio PA", gpio_name);
if (res)
printk(KERN_CRIT "err: PA irq for gpio\n");
return res;
}
/* this makes sure that gpio_init is called during kernel boot */
module_init(gpio_init);