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/* $Id: gpio.c,v 1.12 2001/11/12 19:42:15 pkj Exp $
*
* Etrax general port I/O device
*
* Copyright (c) 1999, 2000, 2001 Axis Communications AB
*
* Authors: Bjorn Wesen (initial version)
* Ola Knutsson (LED handling)
* Johan Adolfsson (read/set directions, write)
*
* $Log: gpio.c,v $
* Revision 1.12 2001/11/12 19:42:15 pkj
* * Corrected return values from gpio_leds_ioctl().
* * Fixed compiler warnings.
*
* Revision 1.11 2001/10/30 14:39:12 johana
* Added D() around gpio_write printk.
*
* Revision 1.10 2001/10/25 10:24:42 johana
* Added IO_CFG_WRITE_MODE ioctl and write method that can do fast
* bittoggling in the kernel. (This speeds up programming an FPGA with 450kB
* from ~60 seconds to 4 seconds).
* Added save_flags/cli/restore_flags in ioctl.
*
* Revision 1.9 2001/05/04 14:16:07 matsfg
* Corrected spelling error
*
* Revision 1.8 2001/04/27 13:55:26 matsfg
* Moved initioremap.
* Turns off all LEDS on init.
* Added support for shutdown and powerbutton.
*
* Revision 1.7 2001/04/04 13:30:08 matsfg
* Added bitset and bitclear for leds. Calls init_ioremap to set up memmapping
*
* Revision 1.6 2001/03/26 16:03:06 bjornw
* Needs linux/config.h
*
* Revision 1.5 2001/03/26 14:22:03 bjornw
* Namechange of some config options
*
* Revision 1.4 2001/02/27 13:52:48 bjornw
* malloc.h -> slab.h
*
* Revision 1.3 2001/01/24 15:06:48 bjornw
* gpio_wq correct type
*
* Revision 1.2 2001/01/18 16:07:30 bjornw
* 2.4 port
*
* Revision 1.1 2001/01/18 15:55:16 bjornw
* Verbatim copy of etraxgpio.c from elinux 2.0 added
*
*
*/
#include <linux/config.h>
#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/string.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <asm/etraxgpio.h>
#include <asm/svinto.h>
#include <asm/io.h>
#include <asm/system.h>
#define GPIO_MAJOR 120 /* experimental MAJOR number */
#define D(x)
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 * 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;
volatile unsigned char *port, *shadow;
volatile unsigned char *dir, *dir_shadow;
unsigned char changeable_dir;
unsigned char changeable_bits;
unsigned char highalarm, lowalarm;
unsigned char clk_mask;
unsigned char data_mask;
unsigned char write_msb;
wait_queue_head_t alarm_wq;
int minor;
};
/* linked list of alarms to check for */
static struct gpio_private *alarmlist = 0;
#define NUM_PORTS 2
static volatile unsigned char *ports[2] = { R_PORT_PA_DATA, R_PORT_PB_DATA };
static volatile unsigned char *shads[2] = {
&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[2] = { CONFIG_ETRAX_PA_CHANGEABLE_DIR,
CONFIG_ETRAX_PB_CHANGEABLE_DIR };
static unsigned char changeable_bits[2] = { CONFIG_ETRAX_PA_CHANGEABLE_BITS,
CONFIG_ETRAX_PB_CHANGEABLE_BITS };
static volatile unsigned char *dir[2] = { R_PORT_PA_DIR, R_PORT_PB_DIR };
static volatile unsigned char *dir_shadow[2] = {
&port_pa_dir_shadow, &port_pb_dir_shadow };
#define LEDS 2
static unsigned int
gpio_poll(struct file *filp,
struct poll_table_struct *wait)
{
/* TODO poll on alarms! */
#if 0
if (!ANYTHING_WANTED) {
D(printk("gpio_select sleeping task\n"));
select_wait(&gpio_wq, table);
return 0;
}
D(printk("gpio_select ready\n"));
#endif
return 1;
}
static ssize_t gpio_write(struct file * file, const char * buf, size_t count,
loff_t *off)
{
struct gpio_private *priv = (struct gpio_private *)file->private_data;
unsigned char data, clk_mask, data_mask, write_msb;
unsigned long flags;
ssize_t retval = count;
if (verify_area(VERIFY_READ, buf, count)) {
return -EFAULT;
}
clk_mask = priv->clk_mask;
data_mask = priv->data_mask;
/* It must have been configured using the IO_CFG_WRITE_MODE */
/* Perhaps a better error code? */
if (clk_mask == 0 || data_mask == 0) {
return -EPERM;
}
write_msb = priv->write_msb;
D(printk("gpio_write: %lu to data 0x%02X clk 0x%02X msb: %i\n",count, data_mask, clk_mask, write_msb));
while (count--) {
int i;
data = *buf++;
if (priv->write_msb) {
for (i = 7; i >= 0;i--) {
save_flags(flags); cli();
*priv->port = *priv->shadow &= ~clk_mask;
if (data & 1<<i)
*priv->port = *priv->shadow |= data_mask;
else
*priv->port = *priv->shadow &= ~data_mask;
/* For FPGA: min 5.0ns (DCC) before CCLK high */
*priv->port = *priv->shadow |= clk_mask;
restore_flags(flags);
}
} else {
for (i = 0; i <= 7;i++) {
save_flags(flags); cli();
*priv->port = *priv->shadow &= ~clk_mask;
if (data & 1<<i)
*priv->port = *priv->shadow |= data_mask;
else
*priv->port = *priv->shadow &= ~data_mask;
/* For FPGA: min 5.0ns (DCC) before CCLK high */
*priv->port = *priv->shadow |= clk_mask;
restore_flags(flags);
}
}
}
return retval;
}
static int
gpio_open(struct inode *inode, struct file *filp)
{
struct gpio_private *priv;
int p = MINOR(inode->i_rdev);
if (p >= NUM_PORTS && p != LEDS)
return -EINVAL;
priv = (struct gpio_private *)kmalloc(sizeof(struct gpio_private),
GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->minor = p;
/* initialize the io/alarm struct and link it into our alarmlist */
priv->next = alarmlist;
alarmlist = priv;
priv->port = ports[p];
priv->shadow = shads[p];
priv->changeable_dir = changeable_dir[p];
priv->changeable_bits = changeable_bits[p];
priv->dir = dir[p];
priv->dir_shadow = dir_shadow[p];
priv->highalarm = 0;
priv->lowalarm = 0;
priv->clk_mask = 0;
priv->data_mask = 0;
init_waitqueue_head(&priv->alarm_wq);
filp->private_data = (void *)priv;
return 0;
}
static int
gpio_release(struct inode *inode, struct file *filp)
{
struct gpio_private *p = alarmlist;
struct gpio_private *todel = (struct gpio_private *)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);
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().
*/
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;
struct gpio_private *priv = (struct gpio_private *)file->private_data;
if (_IOC_TYPE(cmd) != ETRAXGPIO_IOCTYPE) {
return -EINVAL;
}
switch (_IOC_NR(cmd)) {
case IO_READBITS:
// read the port
return *priv->port;
case IO_SETBITS:
save_flags(flags); cli();
// set changeable bits with a 1 in arg
*priv->port = *priv->shadow |=
((unsigned char)arg & priv->changeable_bits);
restore_flags(flags);
break;
case IO_CLRBITS:
save_flags(flags); cli();
// clear changeable bits with a 1 in arg
*priv->port = *priv->shadow &=
~((unsigned char)arg & priv->changeable_bits);
restore_flags(flags);
break;
case IO_HIGHALARM:
// set alarm when bits with 1 in arg go high
priv->highalarm |= (unsigned char)arg;
break;
case IO_LOWALARM:
// set alarm when bits with 1 in arg go low
priv->lowalarm |= (unsigned char)arg;
break;
case IO_CLRALARM:
// clear alarm for bits with 1 in arg
priv->highalarm &= ~(unsigned char)arg;
priv->lowalarm &= ~(unsigned char)arg;
break;
case IO_READDIR:
/* Read direction 0=input 1=output */
return *priv->dir_shadow;
case IO_SETINPUT:
save_flags(flags); cli();
/* Set direction 0=unchanged 1=input */
*priv->dir = *priv->dir_shadow &=
~((unsigned char)arg & priv->changeable_dir);
restore_flags(flags);
return *priv->dir_shadow;
case IO_SETOUTPUT:
save_flags(flags); cli();
/* Set direction 0=unchanged 1=output */
*priv->dir = *priv->dir_shadow |=
((unsigned char)arg & priv->changeable_dir);
restore_flags(flags);
return *priv->dir_shadow;
case IO_SHUTDOWN:
SOFT_SHUTDOWN();
break;
case IO_GET_PWR_BT:
#if defined (CONFIG_ETRAX_SOFT_SHUTDOWN)
return (*R_PORT_G_DATA &
( 1 << CONFIG_ETRAX_POWERBUTTON_BIT));
#else
return 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;
return -EPERM;
}
break;
default:
if (priv->minor == LEDS)
return gpio_leds_ioctl(cmd, arg);
else
return -EINVAL;
}
return 0;
}
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;
LED_ACTIVE_SET_G(green);
LED_ACTIVE_SET_R(red);
break;
case IO_LED_SETBIT:
LED_BIT_SET(arg);
break;
case IO_LED_CLRBIT:
LED_BIT_CLR(arg);
break;
default:
return -EINVAL;
}
return 0;
}
struct file_operations gpio_fops = {
owner: THIS_MODULE,
poll: gpio_poll,
ioctl: gpio_ioctl,
write: gpio_write,
open: gpio_open,
release: gpio_release,
};
/* main driver initialization routine, called from mem.c */
static __init int
gpio_init(void)
{
extern void init_ioremap(void);
int res;
#if defined (CONFIG_ETRAX_CSP0_LEDS)
int i;
#endif
/* do the formalities */
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)
init_ioremap();
LED_NETWORK_SET(0);
LED_ACTIVE_SET(0);
LED_DISK_READ(0);
LED_DISK_WRITE(0);
#if defined (CONFIG_ETRAX_CSP0_LEDS)
for (i = 0; i < 32; i++) {
LED_BIT_SET(i);
}
#endif
#endif
printk("ETRAX 100LX GPIO driver v2.2, (c) 2001 Axis Communications AB\n");
return res;
}
/* this makes sure that gpio_init is called during kernel boot */
module_init(gpio_init);
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