[PATCH 28/57] mtx-1_wdt: clean up, coding style, unlocked ioctl

Alan Cox
2008-05-19T13:27:30Z

drivers/watchdog/mtx-1_wdt.c | 107 ++++++++++++++++++++----------------------
1 files changed, 52 insertions(+), 55 deletions(-)

diff --git a/drivers/watchdog/mtx-1_wdt.c b/drivers/watchdog/mtx-1_wdt.c
index a8e6738..e0b8cdf 100644
--- a/drivers/watchdog/mtx-1_wdt.c
+++ b/drivers/watchdog/mtx-1_wdt.c
@@ -1,7 +1,8 @@
/*
* Driver for the MTX-1 Watchdog.
*
- * (C) Copyright 2005 4G Systems <info@4g-systems.biz>, All Rights Reserved.
+ * (C) Copyright 2005 4G Systems <info@4g-systems.biz>,
+ * All Rights Reserved.
* http://www.4g-systems.biz
*
* (C) Copyright 2007 OpenWrt.org, Florian Fainelli <florian@openwrt.org>
@@ -46,12 +47,11 @@
#include <linux/jiffies.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
-
-#include <asm/io.h>
-#include <asm/uaccess.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/gpio.h>

#include <asm/mach-au1x00/au1000.h>
-#include <asm/gpio.h>

#define MTX1_WDT_INTERVAL (5 * HZ)

@@ -59,6 +59,7 @@ static int ticks = 100 * HZ;

static struct {
struct completion stop;
+ spinlock_t lock;
int running;
struct timer_list timer;
int queue;
@@ -71,6 +72,7 @@ static void mtx1_wdt_trigger(unsigned long unused)
{
u32 tmp;

+ spin_lock(&mtx1_wdt_device.lock);
if (mtx1_wdt_device.running)
ticks--;
/*
@@ -79,13 +81,13 @@ static void mtx1_wdt_trigger(unsigned long unused)
tmp = au_readl(GPIO2_DIR);
tmp = (tmp & ~(1 << mtx1_wdt_device.gpio)) |
((~tmp) & (1 << mtx1_wdt_device.gpio));
- au_writel (tmp, GPIO2_DIR);
+ au_writel(tmp, GPIO2_DIR);

if (mtx1_wdt_device.queue && ticks)
mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
- else {
+ else
complete(&mtx1_wdt_device.stop);
- }
+ spin_unlock(&mtx1_wdt_device.lock);
}

static void mtx1_wdt_reset(void)
@@ -96,23 +98,25 @@ static void mtx1_wdt_reset(void)

static void mtx1_wdt_start(void)
{
+ spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
if (!mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 1;
gpio_set_value(mtx1_wdt_device.gpio, 1);
mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
}
mtx1_wdt_device.running++;
+ spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags);
}

static int mtx1_wdt_stop(void)
{
+ spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
if (mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 0;
gpio_set_value(mtx1_wdt_device.gpio, 0);
}
-
ticks = mtx1_wdt_device.default_ticks;
-
+ spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags);
return 0;
}

@@ -122,7 +126,6 @@ static int mtx1_wdt_open(struct inode *inode, struct file *file)
{
if (test_and_set_bit(0, &mtx1_wdt_device.inuse))
return -EBUSY;
-
return nonseekable_open(inode, file);
}

@@ -133,54 +136,51 @@ static int mtx1_wdt_release(struct inode *inode, struct file *file)
return 0;
}

-static int mtx1_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+static long mtx1_wdt_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
{
void __user *argp = (void __user *)arg;
+ int __user *p = (int __user *)argp;
unsigned int value;
- static struct watchdog_info ident =
- {
+ static const struct watchdog_info ident = {
.options = WDIOF_CARDRESET,
.identity = "MTX-1 WDT",
};

- switch(cmd) {
- case WDIOC_KEEPALIVE:
- mtx1_wdt_reset();
- break;
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- if ( copy_to_user(argp, &value, sizeof(int)) )
- return -EFAULT;
- break;
- case WDIOC_GETSUPPORT:
- if ( copy_to_user(argp, &ident, sizeof(ident)) )
- return -EFAULT;
- break;
- case WDIOC_SETOPTIONS:
- if ( copy_from_user(&value, argp, sizeof(int)) )
- return -EFAULT;
- switch(value) {
- case WDIOS_ENABLECARD:
- mtx1_wdt_start();
- break;
- case WDIOS_DISABLECARD:
- return mtx1_wdt_stop();
- default:
- return -EINVAL;
- }
- break;
- default:
- return -ENOTTY;
+ switch (cmd) {
+ case WDIOC_KEEPALIVE:
+ mtx1_wdt_reset();
+ break;
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ put_user(0, p);
+ break;
+ case WDIOC_GETSUPPORT:
+ if (copy_to_user(argp, &ident, sizeof(ident)))
+ return -EFAULT;
+ break;
+ case WDIOC_SETOPTIONS:
+ if (get_user(value, p))
+ return -EFAULT;
+ if (value & WDIOS_ENABLECARD)
+ mtx1_wdt_start();
+ else if (value & WDIOS_DISABLECARD)
+ mtx1_wdt_stop();
+ else
+ return -EINVAL;
+ return 0;
+ default:
+ return -ENOTTY;
}
return 0;
}

-static ssize_t mtx1_wdt_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
+static ssize_t mtx1_wdt_write(struct file *file, const char *buf,
+ size_t count, loff_t *ppos)
{
if (!count)
return -EIO;
-
mtx1_wdt_reset();
return count;
}
@@ -188,7 +188,7 @@ static ssize_t mtx1_wdt_write(struct file *file, const char *buf, size_t count,
static const struct file_operations mtx1_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
- .ioctl = mtx1_wdt_ioctl,
+ .unlocked_ioctl = mtx1_wdt_ioctl,
.open = mtx1_wdt_open,
.write = mtx1_wdt_write,
.release = mtx1_wdt_release
@@ -208,29 +208,26 @@ static int mtx1_wdt_probe(struct platform_device *pdev)

mtx1_wdt_device.gpio = pdev->resource[0].start;

- if ((ret = misc_register(&mtx1_wdt_misc)) < 0) {
- printk(KERN_ERR " mtx-1_wdt : failed to register\n");
- return ret;
- }
-
+ spin_lock_init(&mtx1_wdt_device.lock);
init_completion(&mtx1_wdt_device.stop);
mtx1_wdt_device.queue = 0;
-
clear_bit(0, &mtx1_wdt_device.inuse);
-
setup_timer(&mtx1_wdt_device.timer, mtx1_wdt_trigger, 0L);
-
mtx1_wdt_device.default_ticks = ticks;

+ ret = misc_register(&mtx1_wdt_misc);
+ if (ret < 0) {
+ printk(KERN_ERR " mtx-1_wdt : failed to register\n");
+ return ret;
+ }
mtx1_wdt_start();
-
printk(KERN_INFO "MTX-1 Watchdog driver\n");
-
return 0;
}

static int mtx1_wdt_remove(struct platform_device *pdev)
{
+ /* FIXME: do we need to lock this test ? */
if (mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 0;
wait_for_completion(&mtx1_wdt_device.stop);