[PATCH 04/10] watchdog: imx2: Convert to use infrastructure triggered keepalives


Maxim Yu, Osipov
 

From: Guenter Roeck <linux@...>

commit 11d7aba9ceb726d86aaaca3eb5f7d79de38989c5 upstream.

The watchdog infrastructure now supports handling watchdog keepalive
if the watchdog is running while the watchdog device is closed.
Convert the driver to use this infrastructure.

Signed-off-by: Guenter Roeck <linux@...>
Signed-off-by: Wim Van Sebroeck <wim@...>
[mosipov@... backported to 4.4.y]
Signed-off-by: Maxim Yu. Osipov <mosipov@...>
---
drivers/watchdog/imx2_wdt.c | 74 ++++++++-------------------------------------
1 file changed, 13 insertions(+), 61 deletions(-)

diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index 29ef719a6a3c..378e7c5dfc50 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -25,7 +25,6 @@
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/io.h>
-#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
@@ -34,7 +33,6 @@
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <linux/regmap.h>
-#include <linux/timer.h>
#include <linux/watchdog.h>

#define DRIVER_NAME "imx2-wdt"
@@ -62,7 +60,6 @@
struct imx2_wdt_device {
struct clk *clk;
struct regmap *regmap;
- struct timer_list timer; /* Pings the watchdog when closed */
struct watchdog_device wdog;
struct notifier_block restart_handler;
};
@@ -151,16 +148,6 @@ static int imx2_wdt_ping(struct watchdog_device *wdog)
return 0;
}

-static void imx2_wdt_timer_ping(unsigned long arg)
-{
- struct watchdog_device *wdog = (struct watchdog_device *)arg;
- struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
-
- /* ping it every wdog->timeout / 2 seconds to prevent reboot */
- imx2_wdt_ping(wdog);
- mod_timer(&wdev->timer, jiffies + wdog->timeout * HZ / 2);
-}
-
static int imx2_wdt_set_timeout(struct watchdog_device *wdog,
unsigned int new_timeout)
{
@@ -177,40 +164,19 @@ static int imx2_wdt_start(struct watchdog_device *wdog)
{
struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);

- if (imx2_wdt_is_running(wdev)) {
- /* delete the timer that pings the watchdog after close */
- del_timer_sync(&wdev->timer);
+ if (imx2_wdt_is_running(wdev))
imx2_wdt_set_timeout(wdog, wdog->timeout);
- } else
+ else
imx2_wdt_setup(wdog);

- return imx2_wdt_ping(wdog);
-}
-
-static int imx2_wdt_stop(struct watchdog_device *wdog)
-{
- /*
- * We don't need a clk_disable, it cannot be disabled once started.
- * We use a timer to ping the watchdog while /dev/watchdog is closed
- */
- imx2_wdt_timer_ping((unsigned long)wdog);
- return 0;
-}
-
-static inline void imx2_wdt_ping_if_active(struct watchdog_device *wdog)
-{
- struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
+ set_bit(WDOG_HW_RUNNING, &wdog->status);

- if (imx2_wdt_is_running(wdev)) {
- imx2_wdt_set_timeout(wdog, wdog->timeout);
- imx2_wdt_timer_ping((unsigned long)wdog);
- }
+ return imx2_wdt_ping(wdog);
}

static const struct watchdog_ops imx2_wdt_ops = {
.owner = THIS_MODULE,
.start = imx2_wdt_start,
- .stop = imx2_wdt_stop,
.ping = imx2_wdt_ping,
.set_timeout = imx2_wdt_set_timeout,
};
@@ -257,7 +223,7 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
wdog->info = &imx2_wdt_info;
wdog->ops = &imx2_wdt_ops;
wdog->min_timeout = 1;
- wdog->max_timeout = IMX2_WDT_MAX_TIME;
+ wdog->max_hw_heartbeat_ms = IMX2_WDT_MAX_TIME * 1000;
wdog->parent = &pdev->dev;

ret = clk_prepare_enable(wdev->clk);
@@ -277,9 +243,10 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
watchdog_set_nowayout(wdog, nowayout);
watchdog_init_timeout(wdog, timeout, &pdev->dev);

- setup_timer(&wdev->timer, imx2_wdt_timer_ping, (unsigned long)wdog);
-
- imx2_wdt_ping_if_active(wdog);
+ if (imx2_wdt_is_running(wdev)) {
+ imx2_wdt_set_timeout(wdog, wdog->timeout);
+ set_bit(WDOG_HW_RUNNING, &wdog->status);
+ }

/*
* Disable the watchdog power down counter at boot. Otherwise the power
@@ -320,7 +287,6 @@ static int __exit imx2_wdt_remove(struct platform_device *pdev)
watchdog_unregister_device(wdog);

if (imx2_wdt_is_running(wdev)) {
- del_timer_sync(&wdev->timer);
imx2_wdt_ping(wdog);
dev_crit(&pdev->dev, "Device removed: Expect reboot!\n");
}
@@ -334,10 +300,9 @@ static void imx2_wdt_shutdown(struct platform_device *pdev)

if (imx2_wdt_is_running(wdev)) {
/*
- * We are running, we need to delete the timer but will
- * give max timeout before reboot will take place
+ * We are running, configure max timeout before reboot
+ * will take place.
*/
- del_timer_sync(&wdev->timer);
imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME);
imx2_wdt_ping(wdog);
dev_crit(&pdev->dev, "Device shutdown: Expect reboot!\n");
@@ -355,10 +320,6 @@ static int imx2_wdt_suspend(struct device *dev)
if (imx2_wdt_is_running(wdev)) {
imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME);
imx2_wdt_ping(wdog);
-
- /* The watchdog is not active */
- if (!watchdog_active(wdog))
- del_timer_sync(&wdev->timer);
}

clk_disable_unprepare(wdev->clk);
@@ -384,19 +345,10 @@ static int imx2_wdt_resume(struct device *dev)
* watchdog again.
*/
imx2_wdt_setup(wdog);
+ }
+ if (imx2_wdt_is_running(wdev)) {
imx2_wdt_set_timeout(wdog, wdog->timeout);
imx2_wdt_ping(wdog);
- } else if (imx2_wdt_is_running(wdev)) {
- /* Resuming from non-deep sleep state. */
- imx2_wdt_set_timeout(wdog, wdog->timeout);
- imx2_wdt_ping(wdog);
- /*
- * But the watchdog is not active, then start
- * the timer again.
- */
- if (!watchdog_active(wdog))
- mod_timer(&wdev->timer,
- jiffies + wdog->timeout * HZ / 2);
}

return 0;
--
2.11.0

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