kernel-ark/drivers/watchdog/twl4030_wdt.c

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/*
* Copyright (C) Nokia Corporation
*
* Written by Timo Kokkonen <timo.t.kokkonen at nokia.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; 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/module.h>
#include <linux/types.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/miscdevice.h>
#include <linux/uaccess.h>
#include <linux/i2c/twl.h>
#define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3
#define TWL4030_WDT_STATE_OPEN 0x1
#define TWL4030_WDT_STATE_ACTIVE 0x8
static struct platform_device *twl4030_wdt_dev;
struct twl4030_wdt {
struct miscdevice miscdev;
int timer_margin;
unsigned long state;
};
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 int twl4030_wdt_write(unsigned char val)
{
return twl_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, val,
TWL4030_WATCHDOG_CFG_REG_OFFS);
}
static int twl4030_wdt_enable(struct twl4030_wdt *wdt)
{
return twl4030_wdt_write(wdt->timer_margin + 1);
}
static int twl4030_wdt_disable(struct twl4030_wdt *wdt)
{
return twl4030_wdt_write(0);
}
static int twl4030_wdt_set_timeout(struct twl4030_wdt *wdt, int timeout)
{
if (timeout < 0 || timeout > 30) {
dev_warn(wdt->miscdev.parent,
"Timeout can only be in the range [0-30] seconds");
return -EINVAL;
}
wdt->timer_margin = timeout;
return twl4030_wdt_enable(wdt);
}
static ssize_t twl4030_wdt_write_fop(struct file *file,
const char __user *data, size_t len, loff_t *ppos)
{
struct twl4030_wdt *wdt = file->private_data;
if (len)
twl4030_wdt_enable(wdt);
return len;
}
static long twl4030_wdt_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = argp;
int new_margin;
struct twl4030_wdt *wdt = file->private_data;
static const struct watchdog_info twl4030_wd_ident = {
.identity = "TWL4030 Watchdog",
.options = WDIOF_SETTIMEOUT,
.firmware_version = 0,
};
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &twl4030_wd_ident,
sizeof(twl4030_wd_ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_KEEPALIVE:
twl4030_wdt_enable(wdt);
break;
case WDIOC_SETTIMEOUT:
if (get_user(new_margin, p))
return -EFAULT;
if (twl4030_wdt_set_timeout(wdt, new_margin))
return -EINVAL;
return put_user(wdt->timer_margin, p);
case WDIOC_GETTIMEOUT:
return put_user(wdt->timer_margin, p);
default:
return -ENOTTY;
}
return 0;
}
static int twl4030_wdt_open(struct inode *inode, struct file *file)
{
struct twl4030_wdt *wdt = platform_get_drvdata(twl4030_wdt_dev);
/* /dev/watchdog can only be opened once */
if (test_and_set_bit(0, &wdt->state))
return -EBUSY;
wdt->state |= TWL4030_WDT_STATE_ACTIVE;
file->private_data = (void *) wdt;
twl4030_wdt_enable(wdt);
return nonseekable_open(inode, file);
}
static int twl4030_wdt_release(struct inode *inode, struct file *file)
{
struct twl4030_wdt *wdt = file->private_data;
if (nowayout) {
dev_alert(wdt->miscdev.parent,
"Unexpected close, watchdog still running!\n");
twl4030_wdt_enable(wdt);
} else {
if (twl4030_wdt_disable(wdt))
return -EFAULT;
wdt->state &= ~TWL4030_WDT_STATE_ACTIVE;
}
clear_bit(0, &wdt->state);
return 0;
}
static const struct file_operations twl4030_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.open = twl4030_wdt_open,
.release = twl4030_wdt_release,
.unlocked_ioctl = twl4030_wdt_ioctl,
.write = twl4030_wdt_write_fop,
};
static int __devinit twl4030_wdt_probe(struct platform_device *pdev)
{
int ret = 0;
struct twl4030_wdt *wdt;
wdt = kzalloc(sizeof(struct twl4030_wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
wdt->state = 0;
wdt->timer_margin = 30;
wdt->miscdev.parent = &pdev->dev;
wdt->miscdev.fops = &twl4030_wdt_fops;
wdt->miscdev.minor = WATCHDOG_MINOR;
wdt->miscdev.name = "watchdog";
platform_set_drvdata(pdev, wdt);
twl4030_wdt_dev = pdev;
twl4030_wdt_disable(wdt);
ret = misc_register(&wdt->miscdev);
if (ret) {
dev_err(wdt->miscdev.parent,
"Failed to register misc device\n");
platform_set_drvdata(pdev, NULL);
kfree(wdt);
twl4030_wdt_dev = NULL;
return ret;
}
return 0;
}
static int __devexit twl4030_wdt_remove(struct platform_device *pdev)
{
struct twl4030_wdt *wdt = platform_get_drvdata(pdev);
if (wdt->state & TWL4030_WDT_STATE_ACTIVE)
if (twl4030_wdt_disable(wdt))
return -EFAULT;
wdt->state &= ~TWL4030_WDT_STATE_ACTIVE;
misc_deregister(&wdt->miscdev);
platform_set_drvdata(pdev, NULL);
kfree(wdt);
twl4030_wdt_dev = NULL;
return 0;
}
#ifdef CONFIG_PM
static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
{
struct twl4030_wdt *wdt = platform_get_drvdata(pdev);
if (wdt->state & TWL4030_WDT_STATE_ACTIVE)
return twl4030_wdt_disable(wdt);
return 0;
}
static int twl4030_wdt_resume(struct platform_device *pdev)
{
struct twl4030_wdt *wdt = platform_get_drvdata(pdev);
if (wdt->state & TWL4030_WDT_STATE_ACTIVE)
return twl4030_wdt_enable(wdt);
return 0;
}
#else
#define twl4030_wdt_suspend NULL
#define twl4030_wdt_resume NULL
#endif
static struct platform_driver twl4030_wdt_driver = {
.probe = twl4030_wdt_probe,
.remove = __devexit_p(twl4030_wdt_remove),
.suspend = twl4030_wdt_suspend,
.resume = twl4030_wdt_resume,
.driver = {
.owner = THIS_MODULE,
.name = "twl4030_wdt",
},
};
static int __devinit twl4030_wdt_init(void)
{
return platform_driver_register(&twl4030_wdt_driver);
}
module_init(twl4030_wdt_init);
static void __devexit twl4030_wdt_exit(void)
{
platform_driver_unregister(&twl4030_wdt_driver);
}
module_exit(twl4030_wdt_exit);
MODULE_AUTHOR("Nokia Corporation");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS("platform:twl4030_wdt");