Change the "at91_wdt_settimeout" function name to "at91wdt_enable" for more reasonable, and also set the drvdata->enabled value. Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx> --- drivers/watchdog/at91sam9_wdt.c | 28 +++++++++++++++++----------- 1 file changed, 17 insertions(+), 11 deletions(-) diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c index 98e7d5a..e2d6111 100644 --- a/drivers/watchdog/at91sam9_wdt.c +++ b/drivers/watchdog/at91sam9_wdt.c @@ -13,6 +13,9 @@ * The Watchdog Timer Mode Register can be only written to once. If the * timeout need to be set from Linux, be sure that the bootstrap or the * bootloader doesn't write to this register. + * The Watchdog Timer default is running with maximum counter value + * (WDV=0xfff) at reset, i.e., at power-up. It MUST be either disabled + * or be reprogrammed within the maxinum margin(16s). */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt @@ -105,20 +108,20 @@ static void at91_ping(unsigned long data) pr_crit("I will reset your machine !\n"); } -/* - * Set the watchdog time interval in 1/256Hz (write-once) - * Counter is 12 bit. - */ -static int at91_wdt_settimeout(struct watchdog_device *wddev, - unsigned int timeout) +static int at91wdt_enable(struct watchdog_device *wddev, unsigned int timeout) { struct at91wdt_drvdata *driver_data = watchdog_get_drvdata(wddev); unsigned int reg; unsigned int mr; - /* Check if disabled */ + /* Check if the watchdog is disabled, + * if disabled, the reason is the bootstrap or the bootloader has + * written the Watchdog Timer Mode Register to disable the + * watchdog timer + */ mr = wdt_read(driver_data, AT91_WDT_MR); if (mr & AT91_WDT_WDDIS) { + driver_data->enabled = false; pr_err("sorry, watchdog is disabled\n"); return -EIO; } @@ -136,6 +139,8 @@ static int at91_wdt_settimeout(struct watchdog_device *wddev, | (timeout & AT91_WDT_WDV); /* timer value */ wdt_write(driver_data, AT91_WDT_MR, reg); + driver_data->enabled = true; + return 0; } @@ -169,10 +174,11 @@ static int __init at91wdt_probe(struct platform_device *pdev) watchdog_set_drvdata(&at91_wddev, driver_data); - /* Set watchdog */ - res = at91_wdt_settimeout(ms_to_ticks(WDT_HW_TIMEOUT * 1000)); - if (res) - return res; + res = at91wdt_enable(&at91_wddev); + if (res) { + dev_err(&pdev->dev, "cannot enable watchdog (%d)\n", ret); + return ret; + } driver_data->next_heartbeat = jiffies + heartbeat * HZ; setup_timer(&driver_data->timer, at91_ping, 0); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html