| Message ID | 1405265431-4561-6-git-send-email-linux@roeck-us.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sun, Jul 13, 2014 at 04:30:29PM +0100, Guenter Roeck wrote: > diff --git a/drivers/watchdog/moxart_wdt.c b/drivers/watchdog/moxart_wdt.c > index 4aa3a8a..5080b50 100644 > --- a/drivers/watchdog/moxart_wdt.c > +++ b/drivers/watchdog/moxart_wdt.c [...] > -static void moxart_wdt_restart(enum reboot_mode reboot_mode, const char *cmd) > +static int moxart_restart_notify(struct notifier_block *this, > + unsigned long mode, void *cmd) > { > - writel(1, moxart_restart_ctx->base + REG_COUNT); > - writel(0x5ab9, moxart_restart_ctx->base + REG_MODE); > - writel(0x03, moxart_restart_ctx->base + REG_ENABLE); > + struct moxart_wdt_dev *moxart_wdt = container_of(this, > + struct moxart_wdt_dev, > + restart_notifier); > + writel(1, moxart_wdt->base + REG_COUNT); > + writel(0x5ab9, moxart_wdt->base + REG_MODE); > + writel(0x03, moxart_wdt->base + REG_ENABLE); > + > + return NOTIFY_DONE; > } Wondering whether NOTIFY_OK or even NOTIFY_STOP_MASK is better here.
On 07/14/2014 07:19 AM, Catalin Marinas wrote: > On Sun, Jul 13, 2014 at 04:30:29PM +0100, Guenter Roeck wrote: >> diff --git a/drivers/watchdog/moxart_wdt.c b/drivers/watchdog/moxart_wdt.c >> index 4aa3a8a..5080b50 100644 >> --- a/drivers/watchdog/moxart_wdt.c >> +++ b/drivers/watchdog/moxart_wdt.c > [...] >> -static void moxart_wdt_restart(enum reboot_mode reboot_mode, const char *cmd) >> +static int moxart_restart_notify(struct notifier_block *this, >> + unsigned long mode, void *cmd) >> { >> - writel(1, moxart_restart_ctx->base + REG_COUNT); >> - writel(0x5ab9, moxart_restart_ctx->base + REG_MODE); >> - writel(0x03, moxart_restart_ctx->base + REG_ENABLE); >> + struct moxart_wdt_dev *moxart_wdt = container_of(this, >> + struct moxart_wdt_dev, >> + restart_notifier); >> + writel(1, moxart_wdt->base + REG_COUNT); >> + writel(0x5ab9, moxart_wdt->base + REG_MODE); >> + writel(0x03, moxart_wdt->base + REG_ENABLE); >> + >> + return NOTIFY_DONE; >> } > > Wondering whether NOTIFY_OK or even NOTIFY_STOP_MASK is better here. > Personally I would rather call all of them if more than one notifier is registered to ensure that (at least) one does what it is intended to do, but I am open to suggestions. Guenter
On Mon, Jul 14, 2014 at 03:41:15PM +0100, Guenter Roeck wrote: > On 07/14/2014 07:19 AM, Catalin Marinas wrote: > > On Sun, Jul 13, 2014 at 04:30:29PM +0100, Guenter Roeck wrote: > >> diff --git a/drivers/watchdog/moxart_wdt.c b/drivers/watchdog/moxart_wdt.c > >> index 4aa3a8a..5080b50 100644 > >> --- a/drivers/watchdog/moxart_wdt.c > >> +++ b/drivers/watchdog/moxart_wdt.c > > [...] > >> -static void moxart_wdt_restart(enum reboot_mode reboot_mode, const char *cmd) > >> +static int moxart_restart_notify(struct notifier_block *this, > >> + unsigned long mode, void *cmd) > >> { > >> - writel(1, moxart_restart_ctx->base + REG_COUNT); > >> - writel(0x5ab9, moxart_restart_ctx->base + REG_MODE); > >> - writel(0x03, moxart_restart_ctx->base + REG_ENABLE); > >> + struct moxart_wdt_dev *moxart_wdt = container_of(this, > >> + struct moxart_wdt_dev, > >> + restart_notifier); > >> + writel(1, moxart_wdt->base + REG_COUNT); > >> + writel(0x5ab9, moxart_wdt->base + REG_MODE); > >> + writel(0x03, moxart_wdt->base + REG_ENABLE); > >> + > >> + return NOTIFY_DONE; > >> } > > > > Wondering whether NOTIFY_OK or even NOTIFY_STOP_MASK is better here. > > Personally I would rather call all of them if more than one notifier is > registered to ensure that (at least) one does what it is intended to do, > but I am open to suggestions. Probably fine. I guess there won't be more than one handler registered in most cases anyway.
diff --git a/drivers/watchdog/moxart_wdt.c b/drivers/watchdog/moxart_wdt.c index 4aa3a8a..5080b50 100644 --- a/drivers/watchdog/moxart_wdt.c +++ b/drivers/watchdog/moxart_wdt.c @@ -15,12 +15,12 @@ #include <linux/module.h> #include <linux/err.h> #include <linux/kernel.h> +#include <linux/notifier.h> #include <linux/platform_device.h> +#include <linux/reboot.h> #include <linux/watchdog.h> #include <linux/moduleparam.h> -#include <asm/system_misc.h> - #define REG_COUNT 0x4 #define REG_MODE 0x8 #define REG_ENABLE 0xC @@ -29,17 +29,22 @@ struct moxart_wdt_dev { struct watchdog_device dev; void __iomem *base; unsigned int clock_frequency; + struct notifier_block restart_notifier; }; -static struct moxart_wdt_dev *moxart_restart_ctx; - static int heartbeat; -static void moxart_wdt_restart(enum reboot_mode reboot_mode, const char *cmd) +static int moxart_restart_notify(struct notifier_block *this, + unsigned long mode, void *cmd) { - writel(1, moxart_restart_ctx->base + REG_COUNT); - writel(0x5ab9, moxart_restart_ctx->base + REG_MODE); - writel(0x03, moxart_restart_ctx->base + REG_ENABLE); + struct moxart_wdt_dev *moxart_wdt = container_of(this, + struct moxart_wdt_dev, + restart_notifier); + writel(1, moxart_wdt->base + REG_COUNT); + writel(0x5ab9, moxart_wdt->base + REG_MODE); + writel(0x03, moxart_wdt->base + REG_ENABLE); + + return NOTIFY_DONE; } static int moxart_wdt_stop(struct watchdog_device *wdt_dev) @@ -136,8 +141,12 @@ static int moxart_wdt_probe(struct platform_device *pdev) if (err) return err; - moxart_restart_ctx = moxart_wdt; - arm_pm_restart = moxart_wdt_restart; + moxart_wdt->restart_notifier.notifier_call = moxart_restart_notify; + moxart_wdt->restart_notifier.priority = 128; + err = register_restart_notifier(&moxart_wdt->restart_notifier); + if (err) + dev_err(dev, "cannot register restart notifier (err=%d)\n", + err); dev_dbg(dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)\n", moxart_wdt->dev.timeout, nowayout); @@ -149,9 +158,8 @@ static int moxart_wdt_remove(struct platform_device *pdev) { struct moxart_wdt_dev *moxart_wdt = platform_get_drvdata(pdev); - arm_pm_restart = NULL; + unregister_restart_notifier(&moxart_wdt->restart_notifier); moxart_wdt_stop(&moxart_wdt->dev); - watchdog_unregister_device(&moxart_wdt->dev); return 0; }
The kernel now provides an API to trigger a system restart. Register with it instead of setting arm_pm_restart. Signed-off-by: Guenter Roeck <linux@roeck-us.net> --- v4: Set notifier priority to 128. v3: Move struct notifier_block into struct moxart_wdt_dev. Drop static variable previously needed to access struct moxart_wdt_dev from notifier function; use container_of instead. v2: No change. drivers/watchdog/moxart_wdt.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-)