UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

[WATCHDOG] at32ap700x_wdt.c - Add spinlock support 

Add spinlock support so that forked children can't
do different io stuff at the same time.

Signed-off-by: Hans-Christian Egtvedt <hcegtvedt@atmel.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Wim Van Sebroeck 2007-07-03 17:59:04 +00:00
parent 28401140a2
commit e75e657756
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/char/watchdog/at32ap700x_wdt.c
View File

@ -18,6 +18,7 @@
#include <linux/watchdog.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#define TIMEOUT_MIN 1
#define TIMEOUT_MAX 2
@ -53,6 +54,7 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
struct wdt_at32ap700x {
void __iomem *regs;
spinlock_t io_lock;
int timeout;
int users;
struct miscdevice miscdev;
@ -66,9 +68,11 @@ static char expect_release;
*/
static inline void at32_wdt_stop(void)
{
spin_lock(&wdt->io_lock);
unsigned long psel = wdt_readl(wdt, CTRL) & WDT_BF(CTRL_PSEL, 0x0f);
wdt_writel(wdt, CTRL, psel | WDT_BF(CTRL_KEY, 0x55));
wdt_writel(wdt, CTRL, psel | WDT_BF(CTRL_KEY, 0xaa));
spin_unlock(&wdt->io_lock);
}
/*
@ -79,12 +83,14 @@ static inline void at32_wdt_start(void)
/* 0xf is 2^16 divider = 2 sec, 0xe is 2^15 divider = 1 sec */
unsigned long psel = (wdt->timeout > 1) ? 0xf : 0xe;
spin_lock(&wdt->io_lock);
wdt_writel(wdt, CTRL, WDT_BIT(CTRL_EN)
| WDT_BF(CTRL_PSEL, psel)
| WDT_BF(CTRL_KEY, 0x55));
wdt_writel(wdt, CTRL, WDT_BIT(CTRL_EN)
| WDT_BF(CTRL_PSEL, psel)
| WDT_BF(CTRL_KEY, 0xaa));
spin_unlock(&wdt->io_lock);
}
/*
@ -92,7 +98,9 @@ static inline void at32_wdt_start(void)
*/
static inline void at32_wdt_pat(void)
{
spin_lock(&wdt->io_lock);
wdt_writel(wdt, CLR, 0x42);
spin_unlock(&wdt->io_lock);
}
/*
@ -272,6 +280,7 @@ static int __init at32_wdt_probe(struct platform_device *pdev)
dev_dbg(&pdev->dev, "could not map I/O memory\n");
goto err_free;
}
spin_lock_init(&wdt->io_lock);
wdt->users = 0;
wdt->miscdev.minor = WATCHDOG_MINOR;
wdt->miscdev.name = "watchdog";