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authorGuenter Roeck <linux@roeck-us.net>2016-02-28 13:12:23 -0800
committerWim Van Sebroeck <wim@iguana.be>2017-06-05 20:39:27 +0200
commit03bca15833f2865b11835b7f5bfa594d1aaacecc (patch)
tree6f0f372cafb4b4f71072d884e29a8e1a18e85c25 /drivers/watchdog
parentecd94a41debfd21961c9f59f639dce26f2c779f0 (diff)
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watchdog: gpio: Convert to use infrastructure triggered keepalives
The watchdog infrastructure now supports handling watchdog keepalive if the watchdog is running while the watchdog device is closed. The infrastructure now also supports generating additional heartbeats if the maximum hardware timeout is smaller than or close to the configured timeout. Convert the driver to use this infrastructure. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/gpio_wdt.c73
1 files changed, 13 insertions, 60 deletions
diff --git a/drivers/watchdog/gpio_wdt.c b/drivers/watchdog/gpio_wdt.c
index 93457cabc178..cb66c2f99ff1 100644
--- a/drivers/watchdog/gpio_wdt.c
+++ b/drivers/watchdog/gpio_wdt.c
@@ -18,7 +18,6 @@
#define SOFT_TIMEOUT_MIN 1
#define SOFT_TIMEOUT_DEF 60
-#define SOFT_TIMEOUT_MAX 0xffff
enum {
HW_ALGO_TOGGLE,
@@ -30,11 +29,7 @@ struct gpio_wdt_priv {
bool active_low;
bool state;
bool always_running;
- bool armed;
unsigned int hw_algo;
- unsigned int hw_margin;
- unsigned long last_jiffies;
- struct timer_list timer;
struct watchdog_device wdd;
};
@@ -47,21 +42,10 @@ static void gpio_wdt_disable(struct gpio_wdt_priv *priv)
gpio_direction_input(priv->gpio);
}
-static void gpio_wdt_hwping(unsigned long data)
+static int gpio_wdt_ping(struct watchdog_device *wdd)
{
- struct watchdog_device *wdd = (struct watchdog_device *)data;
struct gpio_wdt_priv *priv = watchdog_get_drvdata(wdd);
- if (priv->armed && time_after(jiffies, priv->last_jiffies +
- msecs_to_jiffies(wdd->timeout * 1000))) {
- dev_crit(wdd->parent,
- "Timer expired. System will reboot soon!\n");
- return;
- }
-
- /* Restart timer */
- mod_timer(&priv->timer, jiffies + priv->hw_margin);
-
switch (priv->hw_algo) {
case HW_ALGO_TOGGLE:
/* Toggle output pin */
@@ -75,55 +59,33 @@ static void gpio_wdt_hwping(unsigned long data)
gpio_set_value_cansleep(priv->gpio, priv->active_low);
break;
}
-}
-
-static void gpio_wdt_start_impl(struct gpio_wdt_priv *priv)
-{
- priv->state = priv->active_low;
- gpio_direction_output(priv->gpio, priv->state);
- priv->last_jiffies = jiffies;
- gpio_wdt_hwping((unsigned long)&priv->wdd);
+ return 0;
}
static int gpio_wdt_start(struct watchdog_device *wdd)
{
struct gpio_wdt_priv *priv = watchdog_get_drvdata(wdd);
- gpio_wdt_start_impl(priv);
- priv->armed = true;
+ priv->state = priv->active_low;
+ gpio_direction_output(priv->gpio, priv->state);
- return 0;
+ set_bit(WDOG_HW_RUNNING, &wdd->status);
+
+ return gpio_wdt_ping(wdd);
}
static int gpio_wdt_stop(struct watchdog_device *wdd)
{
struct gpio_wdt_priv *priv = watchdog_get_drvdata(wdd);
- priv->armed = false;
if (!priv->always_running) {
- mod_timer(&priv->timer, 0);
gpio_wdt_disable(priv);
+ clear_bit(WDOG_HW_RUNNING, &wdd->status);
}
return 0;
}
-static int gpio_wdt_ping(struct watchdog_device *wdd)
-{
- struct gpio_wdt_priv *priv = watchdog_get_drvdata(wdd);
-
- priv->last_jiffies = jiffies;
-
- return 0;
-}
-
-static int gpio_wdt_set_timeout(struct watchdog_device *wdd, unsigned int t)
-{
- wdd->timeout = t;
-
- return gpio_wdt_ping(wdd);
-}
-
static const struct watchdog_info gpio_wdt_ident = {
.options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING |
WDIOF_SETTIMEOUT,
@@ -135,7 +97,6 @@ static const struct watchdog_ops gpio_wdt_ops = {
.start = gpio_wdt_start,
.stop = gpio_wdt_stop,
.ping = gpio_wdt_ping,
- .set_timeout = gpio_wdt_set_timeout,
};
static int gpio_wdt_probe(struct platform_device *pdev)
@@ -185,9 +146,6 @@ static int gpio_wdt_probe(struct platform_device *pdev)
if (hw_margin < 2 || hw_margin > 65535)
return -EINVAL;
- /* Use safe value (1/2 of real timeout) */
- priv->hw_margin = msecs_to_jiffies(hw_margin / 2);
-
priv->always_running = of_property_read_bool(pdev->dev.of_node,
"always-running");
@@ -196,31 +154,26 @@ static int gpio_wdt_probe(struct platform_device *pdev)
priv->wdd.info = &gpio_wdt_ident;
priv->wdd.ops = &gpio_wdt_ops;
priv->wdd.min_timeout = SOFT_TIMEOUT_MIN;
- priv->wdd.max_timeout = SOFT_TIMEOUT_MAX;
+ priv->wdd.max_hw_heartbeat_ms = hw_margin;
priv->wdd.parent = &pdev->dev;
if (watchdog_init_timeout(&priv->wdd, 0, &pdev->dev) < 0)
priv->wdd.timeout = SOFT_TIMEOUT_DEF;
- setup_timer(&priv->timer, gpio_wdt_hwping, (unsigned long)&priv->wdd);
-
watchdog_stop_on_reboot(&priv->wdd);
- ret = watchdog_register_device(&priv->wdd);
- if (ret)
- return ret;
-
if (priv->always_running)
- gpio_wdt_start_impl(priv);
+ gpio_wdt_start(&priv->wdd);
- return 0;
+ ret = watchdog_register_device(&priv->wdd);
+
+ return ret;
}
static int gpio_wdt_remove(struct platform_device *pdev)
{
struct gpio_wdt_priv *priv = platform_get_drvdata(pdev);
- del_timer_sync(&priv->timer);
watchdog_unregister_device(&priv->wdd);
return 0;