mirror of
https://github.com/torvalds/linux.git
synced 2024-11-16 00:52:01 +00:00
b1cf3e99db
The probe and remove functions were incorrectly annotated, with the misannotation of the remove function causing build failures when built in. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
330 lines
6.8 KiB
C
330 lines
6.8 KiB
C
/*
|
|
* Watchdog driver for the wm8350
|
|
*
|
|
* Copyright (C) 2007, 2008 Wolfson Microelectronics <linux@wolfsonmicro.com>
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
#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/platform_device.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/mfd/wm8350/core.h>
|
|
|
|
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) ")");
|
|
|
|
static unsigned long wm8350_wdt_users;
|
|
static struct miscdevice wm8350_wdt_miscdev;
|
|
static int wm8350_wdt_expect_close;
|
|
static DEFINE_MUTEX(wdt_mutex);
|
|
|
|
static struct {
|
|
int time; /* Seconds */
|
|
u16 val; /* To be set in WM8350_SYSTEM_CONTROL_2 */
|
|
} wm8350_wdt_cfgs[] = {
|
|
{ 1, 0x02 },
|
|
{ 2, 0x04 },
|
|
{ 4, 0x05 },
|
|
};
|
|
|
|
static struct wm8350 *get_wm8350(void)
|
|
{
|
|
return dev_get_drvdata(wm8350_wdt_miscdev.parent);
|
|
}
|
|
|
|
static int wm8350_wdt_set_timeout(struct wm8350 *wm8350, u16 value)
|
|
{
|
|
int ret;
|
|
u16 reg;
|
|
|
|
mutex_lock(&wdt_mutex);
|
|
wm8350_reg_unlock(wm8350);
|
|
|
|
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
|
|
reg &= ~WM8350_WDOG_TO_MASK;
|
|
reg |= value;
|
|
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
|
|
|
|
wm8350_reg_lock(wm8350);
|
|
mutex_unlock(&wdt_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int wm8350_wdt_start(struct wm8350 *wm8350)
|
|
{
|
|
int ret;
|
|
u16 reg;
|
|
|
|
mutex_lock(&wdt_mutex);
|
|
wm8350_reg_unlock(wm8350);
|
|
|
|
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
|
|
reg &= ~WM8350_WDOG_MODE_MASK;
|
|
reg |= 0x20;
|
|
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
|
|
|
|
wm8350_reg_lock(wm8350);
|
|
mutex_unlock(&wdt_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int wm8350_wdt_stop(struct wm8350 *wm8350)
|
|
{
|
|
int ret;
|
|
u16 reg;
|
|
|
|
mutex_lock(&wdt_mutex);
|
|
wm8350_reg_unlock(wm8350);
|
|
|
|
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
|
|
reg &= ~WM8350_WDOG_MODE_MASK;
|
|
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
|
|
|
|
wm8350_reg_lock(wm8350);
|
|
mutex_unlock(&wdt_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int wm8350_wdt_kick(struct wm8350 *wm8350)
|
|
{
|
|
int ret;
|
|
u16 reg;
|
|
|
|
mutex_lock(&wdt_mutex);
|
|
|
|
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
|
|
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
|
|
|
|
mutex_unlock(&wdt_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int wm8350_wdt_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct wm8350 *wm8350 = get_wm8350();
|
|
int ret;
|
|
|
|
if (!wm8350)
|
|
return -ENODEV;
|
|
|
|
if (test_and_set_bit(0, &wm8350_wdt_users))
|
|
return -EBUSY;
|
|
|
|
ret = wm8350_wdt_start(wm8350);
|
|
if (ret != 0)
|
|
return ret;
|
|
|
|
return nonseekable_open(inode, file);
|
|
}
|
|
|
|
static int wm8350_wdt_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct wm8350 *wm8350 = get_wm8350();
|
|
|
|
if (wm8350_wdt_expect_close)
|
|
wm8350_wdt_stop(wm8350);
|
|
else {
|
|
dev_warn(wm8350->dev, "Watchdog device closed uncleanly\n");
|
|
wm8350_wdt_kick(wm8350);
|
|
}
|
|
|
|
clear_bit(0, &wm8350_wdt_users);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t wm8350_wdt_write(struct file *file,
|
|
const char __user *data, size_t count,
|
|
loff_t *ppos)
|
|
{
|
|
struct wm8350 *wm8350 = get_wm8350();
|
|
size_t i;
|
|
|
|
if (count) {
|
|
wm8350_wdt_kick(wm8350);
|
|
|
|
if (!nowayout) {
|
|
/* In case it was set long ago */
|
|
wm8350_wdt_expect_close = 0;
|
|
|
|
/* scan to see whether or not we got the magic
|
|
character */
|
|
for (i = 0; i != count; i++) {
|
|
char c;
|
|
if (get_user(c, data + i))
|
|
return -EFAULT;
|
|
if (c == 'V')
|
|
wm8350_wdt_expect_close = 42;
|
|
}
|
|
}
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static struct watchdog_info ident = {
|
|
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
|
|
.identity = "WM8350 Watchdog",
|
|
};
|
|
|
|
static long wm8350_wdt_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct wm8350 *wm8350 = get_wm8350();
|
|
int ret = -ENOTTY, time, i;
|
|
void __user *argp = (void __user *)arg;
|
|
int __user *p = argp;
|
|
u16 reg;
|
|
|
|
switch (cmd) {
|
|
case WDIOC_GETSUPPORT:
|
|
ret = copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
|
|
break;
|
|
|
|
case WDIOC_GETSTATUS:
|
|
case WDIOC_GETBOOTSTATUS:
|
|
ret = put_user(0, p);
|
|
break;
|
|
|
|
case WDIOC_SETOPTIONS:
|
|
{
|
|
int options;
|
|
|
|
if (get_user(options, p))
|
|
return -EFAULT;
|
|
|
|
ret = -EINVAL;
|
|
|
|
/* Setting both simultaneously means at least one must fail */
|
|
if (options == WDIOS_DISABLECARD)
|
|
ret = wm8350_wdt_start(wm8350);
|
|
|
|
if (options == WDIOS_ENABLECARD)
|
|
ret = wm8350_wdt_stop(wm8350);
|
|
break;
|
|
}
|
|
|
|
case WDIOC_KEEPALIVE:
|
|
ret = wm8350_wdt_kick(wm8350);
|
|
break;
|
|
|
|
case WDIOC_SETTIMEOUT:
|
|
ret = get_user(time, p);
|
|
if (ret)
|
|
break;
|
|
|
|
if (time == 0) {
|
|
if (nowayout)
|
|
ret = -EINVAL;
|
|
else
|
|
wm8350_wdt_stop(wm8350);
|
|
break;
|
|
}
|
|
|
|
for (i = 0; i < ARRAY_SIZE(wm8350_wdt_cfgs); i++)
|
|
if (wm8350_wdt_cfgs[i].time == time)
|
|
break;
|
|
if (i == ARRAY_SIZE(wm8350_wdt_cfgs))
|
|
ret = -EINVAL;
|
|
else
|
|
ret = wm8350_wdt_set_timeout(wm8350,
|
|
wm8350_wdt_cfgs[i].val);
|
|
break;
|
|
|
|
case WDIOC_GETTIMEOUT:
|
|
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
|
|
reg &= WM8350_WDOG_TO_MASK;
|
|
for (i = 0; i < ARRAY_SIZE(wm8350_wdt_cfgs); i++)
|
|
if (wm8350_wdt_cfgs[i].val == reg)
|
|
break;
|
|
if (i == ARRAY_SIZE(wm8350_wdt_cfgs)) {
|
|
dev_warn(wm8350->dev,
|
|
"Unknown watchdog configuration: %x\n", reg);
|
|
ret = -EINVAL;
|
|
} else
|
|
ret = put_user(wm8350_wdt_cfgs[i].time, p);
|
|
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations wm8350_wdt_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.write = wm8350_wdt_write,
|
|
.unlocked_ioctl = wm8350_wdt_ioctl,
|
|
.open = wm8350_wdt_open,
|
|
.release = wm8350_wdt_release,
|
|
};
|
|
|
|
static struct miscdevice wm8350_wdt_miscdev = {
|
|
.minor = WATCHDOG_MINOR,
|
|
.name = "watchdog",
|
|
.fops = &wm8350_wdt_fops,
|
|
};
|
|
|
|
static int __devinit wm8350_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
struct wm8350 *wm8350 = platform_get_drvdata(pdev);
|
|
|
|
if (!wm8350) {
|
|
dev_err(wm8350->dev, "No driver data supplied\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* Default to 4s timeout */
|
|
wm8350_wdt_set_timeout(wm8350, 0x05);
|
|
|
|
wm8350_wdt_miscdev.parent = &pdev->dev;
|
|
|
|
return misc_register(&wm8350_wdt_miscdev);
|
|
}
|
|
|
|
static int __devexit wm8350_wdt_remove(struct platform_device *pdev)
|
|
{
|
|
misc_deregister(&wm8350_wdt_miscdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver wm8350_wdt_driver = {
|
|
.probe = wm8350_wdt_probe,
|
|
.remove = __devexit_p(wm8350_wdt_remove),
|
|
.driver = {
|
|
.name = "wm8350-wdt",
|
|
},
|
|
};
|
|
|
|
static int __init wm8350_wdt_init(void)
|
|
{
|
|
return platform_driver_register(&wm8350_wdt_driver);
|
|
}
|
|
module_init(wm8350_wdt_init);
|
|
|
|
static void __exit wm8350_wdt_exit(void)
|
|
{
|
|
platform_driver_unregister(&wm8350_wdt_driver);
|
|
}
|
|
module_exit(wm8350_wdt_exit);
|
|
|
|
MODULE_AUTHOR("Mark Brown");
|
|
MODULE_DESCRIPTION("WM8350 Watchdog");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:wm8350-wdt");
|