Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 99d2853a authored by Wim Van Sebroeck's avatar Wim Van Sebroeck
Browse files

[WATCHDOG] pnx4008_wdt.c - spinlock fixes. 



Add io spinlocks to prevent possible race
conditions between start and stop operations
that are issued from different child processes
where the master process opened /dev/watchdog.

Signed-off-by: default avatarWim Van Sebroeck <wim@iguana.be>
parent f6764497

drivers/char/watchdog/pnx4008_wdt.c

+12 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
#include <linux/device.h>

#include <linux/platform_device.h>

#include <linux/clk.h>

#include <linux/spinlock.h>



#include <asm/hardware.h>

#include <asm/uaccess.h>
@@ -80,6 +81,7 @@ 
static int nowayout = WATCHDOG_NOWAYOUT;

static int heartbeat = DEFAULT_HEARTBEAT;



static spinlock_t io_lock;

static unsigned long wdt_status;

#define WDT_IN_USE        0

#define WDT_OK_TO_CLOSE   1
@@ -94,6 +96,8 @@ struct clk *wdt_clk; 


static void wdt_enable(void)

{

	spin_lock(&io_lock);



	if (wdt_clk)

		clk_set_rate(wdt_clk, 1);
@@ -113,13 +117,19 @@ static void wdt_enable(void) 
	__raw_writel(heartbeat * WDOG_COUNTER_RATE, WDTIM_MATCH0(wdt_base));

	/*enable counter, stop when debugger active */

	__raw_writel(COUNT_ENAB | DEBUG_EN, WDTIM_CTRL(wdt_base));



	spin_unlock(&io_lock);

}



static void wdt_disable(void)

{

	spin_lock(&io_lock);



	__raw_writel(0, WDTIM_CTRL(wdt_base));	/*stop counter */

	if (wdt_clk)

		clk_set_rate(wdt_clk, 0);



	spin_unlock(&io_lock);

}



static int pnx4008_wdt_open(struct inode *inode, struct file *file)
@@ -248,6 +258,8 @@ static int pnx4008_wdt_probe(struct platform_device *pdev) 
	int ret = 0, size;

	struct resource *res;



	spin_lock_init(&io_lock);



	if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)

		heartbeat = DEFAULT_HEARTBEAT;