diff options
author | Alexandre Belloni <alexandre.belloni@free-electrons.com> | 2015-03-12 13:07:28 +0100 |
---|---|---|
committer | Nicolas Ferre <nicolas.ferre@atmel.com> | 2015-03-16 17:03:02 +0100 |
commit | 9ab45f3fb2bebd048ffa2692e8f7cc89f3d379d4 (patch) | |
tree | 05a02c41aac62c2ed8f812ff93cf6414f2ca0204 /drivers/watchdog/at91rm9200_wdt.c | |
parent | 8432f9e5e82a13b82a76171c89b0858e855c9da5 (diff) |
watchdog: at91rm9200: implement restart handler
Restarting the at91rm9200 is done through programming the watchdog and waiting
for it to reset.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Diffstat (limited to 'drivers/watchdog/at91rm9200_wdt.c')
-rw-r--r-- | drivers/watchdog/at91rm9200_wdt.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/watchdog/at91rm9200_wdt.c b/drivers/watchdog/at91rm9200_wdt.c index e6fa87d85de3..41cecb55766c 100644 --- a/drivers/watchdog/at91rm9200_wdt.c +++ b/drivers/watchdog/at91rm9200_wdt.c @@ -12,6 +12,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/bitops.h> +#include <linux/delay.h> #include <linux/errno.h> #include <linux/fs.h> #include <linux/init.h> @@ -23,6 +24,7 @@ #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/platform_device.h> +#include <linux/reboot.h> #include <linux/regmap.h> #include <linux/types.h> #include <linux/watchdog.h> @@ -53,6 +55,27 @@ static unsigned long at91wdt_busy; /* ......................................................................... */ +static int at91rm9200_restart(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + /* + * Perform a hardware reset with the use of the Watchdog timer. + */ + regmap_write(regmap_st, AT91_ST_WDMR, + AT91_ST_RSTEN | AT91_ST_EXTEN | 1); + regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST); + + mdelay(2000); + + pr_emerg("Unable to restart system\n"); + return NOTIFY_DONE; +} + +static struct notifier_block at91rm9200_restart_nb = { + .notifier_call = at91rm9200_restart, + .priority = 192, +}; + /* * Disable the watchdog. */ @@ -228,6 +251,10 @@ static int at91wdt_probe(struct platform_device *pdev) if (res) return res; + res = register_restart_handler(&at91rm9200_restart_nb); + if (res) + dev_warn(dev, "failed to register restart handler\n"); + pr_info("AT91 Watchdog Timer enabled (%d seconds%s)\n", wdt_time, nowayout ? ", nowayout" : ""); return 0; @@ -235,8 +262,13 @@ static int at91wdt_probe(struct platform_device *pdev) static int at91wdt_remove(struct platform_device *pdev) { + struct device *dev = &pdev->dev; int res; + res = unregister_restart_handler(&at91rm9200_restart_nb); + if (res) + dev_warn(dev, "failed to unregister restart handler\n"); + res = misc_deregister(&at91wdt_miscdev); if (!res) at91wdt_miscdev.parent = NULL; |