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android_kernel_motorola_sm6225/drivers/watchdog/w83977f_wdt.c
Alexey Dobriyan c7dfd0cca3 [WATCHDOG] spin_lock_init() fixes 
Some watchdog drivers initialize global spinlocks in module's init function
which is tolerable, but some do it in PCI probe function.  So, switch to
static initialization to fix theoretical bugs and, more importantly, stop
giving people bad examples.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2007-11-02 19:09:07 +00:00

540 lines
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/*
* W83977F Watchdog Timer Driver for Winbond W83977F I/O Chip
*
* (c) Copyright 2005 Jose Goncalves <jose.goncalves@inov.pt>
*
* Based on w83877f_wdt.c by Scott Jennings,
* and wdt977.c by Woody Suwalski
*
* -----------------------
*
* 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.
*
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/watchdog.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#define WATCHDOG_VERSION "1.00"
#define WATCHDOG_NAME "W83977F WDT"
#define PFX WATCHDOG_NAME ": "
#define DRIVER_VERSION WATCHDOG_NAME " driver, v" WATCHDOG_VERSION "\n"
#define IO_INDEX_PORT 0x3F0
#define IO_DATA_PORT (IO_INDEX_PORT+1)
#define UNLOCK_DATA 0x87
#define LOCK_DATA 0xAA
#define DEVICE_REGISTER 0x07
#define DEFAULT_TIMEOUT 45 /* default timeout in seconds */
static int timeout = DEFAULT_TIMEOUT;
static int timeoutW; /* timeout in watchdog counter units */
static unsigned long timer_alive;
static int testmode;
static char expect_close;
static DEFINE_SPINLOCK(spinlock);
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout,"Watchdog timeout in seconds (15..7635), default=" __MODULE_STRING(DEFAULT_TIMEOUT) ")");
module_param(testmode, int, 0);
MODULE_PARM_DESC(testmode,"Watchdog testmode (1 = no reboot), default=0");
static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
/*
* Start the watchdog
*/
static int wdt_start(void)
{
unsigned long flags;
spin_lock_irqsave(&spinlock, flags);
/* Unlock the SuperIO chip */
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
/*
* Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4.
* F2 has the timeout in watchdog counter units.
* F3 is set to enable watchdog LED blink at timeout.
* F4 is used to just clear the TIMEOUT'ed state (bit 0).
*/
outb_p(DEVICE_REGISTER,IO_INDEX_PORT);
outb_p(0x08,IO_DATA_PORT);
outb_p(0xF2,IO_INDEX_PORT);
outb_p(timeoutW,IO_DATA_PORT);
outb_p(0xF3,IO_INDEX_PORT);
outb_p(0x08,IO_DATA_PORT);
outb_p(0xF4,IO_INDEX_PORT);
outb_p(0x00,IO_DATA_PORT);
/* Set device Aux2 active */
outb_p(0x30,IO_INDEX_PORT);
outb_p(0x01,IO_DATA_PORT);
/*
* Select device Aux1 (dev=7) to set GP16 as the watchdog output
* (in reg E6) and GP13 as the watchdog LED output (in reg E3).
* Map GP16 at pin 119.
* In test mode watch the bit 0 on F4 to indicate "triggered" or
* check watchdog LED on SBC.
*/
outb_p(DEVICE_REGISTER,IO_INDEX_PORT);
outb_p(0x07,IO_DATA_PORT);
if (!testmode)
{
unsigned pin_map;
outb_p(0xE6,IO_INDEX_PORT);
outb_p(0x0A,IO_DATA_PORT);
outb_p(0x2C,IO_INDEX_PORT);
pin_map = inb_p(IO_DATA_PORT);
pin_map |= 0x10;
pin_map &= ~(0x20);
outb_p(0x2C,IO_INDEX_PORT);
outb_p(pin_map,IO_DATA_PORT);
}
outb_p(0xE3,IO_INDEX_PORT);
outb_p(0x08,IO_DATA_PORT);
/* Set device Aux1 active */
outb_p(0x30,IO_INDEX_PORT);
outb_p(0x01,IO_DATA_PORT);
/* Lock the SuperIO chip */
outb_p(LOCK_DATA,IO_INDEX_PORT);
spin_unlock_irqrestore(&spinlock, flags);
printk(KERN_INFO PFX "activated.\n");
return 0;
}
/*
* Stop the watchdog
*/
static int wdt_stop(void)
{
unsigned long flags;
spin_lock_irqsave(&spinlock, flags);
/* Unlock the SuperIO chip */
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
/*
* Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4.
* F2 is reset to its default value (watchdog timer disabled).
* F3 is reset to its default state.
* F4 clears the TIMEOUT'ed state (bit 0) - back to default.
*/
outb_p(DEVICE_REGISTER,IO_INDEX_PORT);
outb_p(0x08,IO_DATA_PORT);
outb_p(0xF2,IO_INDEX_PORT);
outb_p(0xFF,IO_DATA_PORT);
outb_p(0xF3,IO_INDEX_PORT);
outb_p(0x00,IO_DATA_PORT);
outb_p(0xF4,IO_INDEX_PORT);
outb_p(0x00,IO_DATA_PORT);
outb_p(0xF2,IO_INDEX_PORT);
outb_p(0x00,IO_DATA_PORT);
/*
* Select device Aux1 (dev=7) to set GP16 (in reg E6) and
* Gp13 (in reg E3) as inputs.
*/
outb_p(DEVICE_REGISTER,IO_INDEX_PORT);
outb_p(0x07,IO_DATA_PORT);
if (!testmode)
{
outb_p(0xE6,IO_INDEX_PORT);
outb_p(0x01,IO_DATA_PORT);
}
outb_p(0xE3,IO_INDEX_PORT);
outb_p(0x01,IO_DATA_PORT);
/* Lock the SuperIO chip */
outb_p(LOCK_DATA,IO_INDEX_PORT);
spin_unlock_irqrestore(&spinlock, flags);
printk(KERN_INFO PFX "shutdown.\n");
return 0;
}
/*
* Send a keepalive ping to the watchdog
* This is done by simply re-writing the timeout to reg. 0xF2
*/
static int wdt_keepalive(void)
{
unsigned long flags;
spin_lock_irqsave(&spinlock, flags);
/* Unlock the SuperIO chip */
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
/* Select device Aux2 (device=8) to kick watchdog reg F2 */
outb_p(DEVICE_REGISTER,IO_INDEX_PORT);
outb_p(0x08,IO_DATA_PORT);
outb_p(0xF2,IO_INDEX_PORT);
outb_p(timeoutW,IO_DATA_PORT);
/* Lock the SuperIO chip */
outb_p(LOCK_DATA,IO_INDEX_PORT);
spin_unlock_irqrestore(&spinlock, flags);
return 0;
}
/*
* Set the watchdog timeout value
*/
static int wdt_set_timeout(int t)
{
int tmrval;
/*
* Convert seconds to watchdog counter time units, rounding up.
* On PCM-5335 watchdog units are 30 seconds/step with 15 sec startup
* value. This information is supplied in the PCM-5335 manual and was
* checked by me on a real board. This is a bit strange because W83977f
* datasheet says counter unit is in minutes!
*/
if (t < 15)
return -EINVAL;
tmrval = ((t + 15) + 29) / 30;
if (tmrval > 255)
return -EINVAL;
/*
* timeout is the timeout in seconds,
* timeoutW is the timeout in watchdog counter units.
*/
timeoutW = tmrval;
timeout = (timeoutW * 30) - 15;
return 0;
}
/*
* Get the watchdog status
*/
static int wdt_get_status(int *status)
{
int new_status;
unsigned long flags;
spin_lock_irqsave(&spinlock, flags);
/* Unlock the SuperIO chip */
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
outb_p(UNLOCK_DATA,IO_INDEX_PORT);
/* Select device Aux2 (device=8) to read watchdog reg F4 */
outb_p(DEVICE_REGISTER,IO_INDEX_PORT);
outb_p(0x08,IO_DATA_PORT);
outb_p(0xF4,IO_INDEX_PORT);
new_status = inb_p(IO_DATA_PORT);
/* Lock the SuperIO chip */
outb_p(LOCK_DATA,IO_INDEX_PORT);
spin_unlock_irqrestore(&spinlock, flags);
*status = 0;
if (new_status & 1)
*status |= WDIOF_CARDRESET;
return 0;
}
/*
* /dev/watchdog handling
*/
static int wdt_open(struct inode *inode, struct file *file)
{
/* If the watchdog is alive we don't need to start it again */
if( test_and_set_bit(0, &timer_alive) )
return -EBUSY;
if (nowayout)
__module_get(THIS_MODULE);
wdt_start();
return nonseekable_open(inode, file);
}
static int wdt_release(struct inode *inode, struct file *file)
{
/*
* Shut off the timer.
* Lock it in if it's a module and we set nowayout
*/
if (expect_close == 42)
{
wdt_stop();
clear_bit(0, &timer_alive);
} else {
wdt_keepalive();
printk(KERN_CRIT PFX "unexpected close, not stopping watchdog!\n");
}
expect_close = 0;
return 0;
}
/*
* wdt_write:
* @file: file handle to the watchdog
* @buf: buffer to write (unused as data does not matter here
* @count: count of bytes
* @ppos: pointer to the position to write. No seeks allowed
*
* A write to a watchdog device is defined as a keepalive signal. Any
* write of data will do, as we we don't define content meaning.
*/
static ssize_t wdt_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
/* See if we got the magic character 'V' and reload the timer */
if(count)
{
if (!nowayout)
{
size_t ofs;
/* note: just in case someone wrote the magic character long ago */
expect_close = 0;
/* scan to see whether or not we got the magic character */
for(ofs = 0; ofs != count; ofs++)
{
char c;
if (get_user(c, buf + ofs))
return -EFAULT;
if (c == 'V') {
expect_close = 42;
}
}
}
/* someone wrote to us, we should restart timer */
wdt_keepalive();
}
return count;
}
/*
* wdt_ioctl:
* @inode: inode of the device
* @file: file handle to the device
* @cmd: watchdog command
* @arg: argument pointer
*
* The watchdog API defines a common set of functions for all watchdogs
* according to their available features.
*/
static struct watchdog_info ident = {
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
.firmware_version = 1,
.identity = WATCHDOG_NAME,
};
static int wdt_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
int status;
int new_options, retval = -EINVAL;
int new_timeout;
union {
struct watchdog_info __user *ident;
int __user *i;
} uarg;
uarg.i = (int __user *)arg;
switch(cmd)
{
default:
return -ENOTTY;
case WDIOC_GETSUPPORT:
return copy_to_user(uarg.ident, &ident, sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
wdt_get_status(&status);
return put_user(status, uarg.i);
case WDIOC_GETBOOTSTATUS:
return put_user(0, uarg.i);
case WDIOC_KEEPALIVE:
wdt_keepalive();
return 0;
case WDIOC_SETOPTIONS:
if (get_user (new_options, uarg.i))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
wdt_stop();
retval = 0;
}
if (new_options & WDIOS_ENABLECARD) {
wdt_start();
retval = 0;
}
return retval;
case WDIOC_SETTIMEOUT:
if (get_user(new_timeout, uarg.i))
return -EFAULT;
if (wdt_set_timeout(new_timeout))
return -EINVAL;
wdt_keepalive();
/* Fall */
case WDIOC_GETTIMEOUT:
return put_user(timeout, uarg.i);
}
}
static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
void *unused)
{
if (code==SYS_DOWN || code==SYS_HALT)
wdt_stop();
return NOTIFY_DONE;
}
static const struct file_operations wdt_fops=
{
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = wdt_write,
.ioctl = wdt_ioctl,
.open = wdt_open,
.release = wdt_release,
};
static struct miscdevice wdt_miscdev=
{
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &wdt_fops,
};
static struct notifier_block wdt_notifier = {
.notifier_call = wdt_notify_sys,
};
static int __init w83977f_wdt_init(void)
{
int rc;
printk(KERN_INFO PFX DRIVER_VERSION);
/*
* Check that the timeout value is within it's range ;
* if not reset to the default
*/
if (wdt_set_timeout(timeout)) {
wdt_set_timeout(DEFAULT_TIMEOUT);
printk(KERN_INFO PFX "timeout value must be 15<=timeout<=7635, using %d\n",
DEFAULT_TIMEOUT);
}
if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME))
{
printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
IO_INDEX_PORT);
rc = -EIO;
goto err_out;
}
rc = misc_register(&wdt_miscdev);
if (rc)
{
printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
wdt_miscdev.minor, rc);
goto err_out_region;
}
rc = register_reboot_notifier(&wdt_notifier);
if (rc)
{
printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
rc);
goto err_out_miscdev;
}
printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d testmode=%d)\n",
timeout, nowayout, testmode);
return 0;
err_out_miscdev:
misc_deregister(&wdt_miscdev);
err_out_region:
release_region(IO_INDEX_PORT,2);
err_out:
return rc;
}
static void __exit w83977f_wdt_exit(void)
{
wdt_stop();
misc_deregister(&wdt_miscdev);
unregister_reboot_notifier(&wdt_notifier);
release_region(IO_INDEX_PORT,2);
}
module_init(w83977f_wdt_init);
module_exit(w83977f_wdt_exit);
MODULE_AUTHOR("Jose Goncalves <jose.goncalves@inov.pt>");
MODULE_DESCRIPTION("Driver for watchdog timer in W83977F I/O chip");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
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