[PATCH 1/4] watchdog: aspeed: Retain watchdog enabled state

Guenter Roeck
2017-09-18T13:25:02Z

On 09/17/2017 10:49 PM, Andrew Jeffery wrote:
> An unintended post-condition of probe() is that the watchdog is
> disabled. Rework probe() such that we retain the value of the "enabled"
> bit from the control register, and take the appropriate actions with
> respect to the watchdog core if so. Otherwise, just configure the
> watchdog as directed.
>
> Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
> ---
> drivers/watchdog/aspeed_wdt.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
> index 79cc766cd30f..99bc6fbd8852 100644
> --- a/drivers/watchdog/aspeed_wdt.c
> +++ b/drivers/watchdog/aspeed_wdt.c
> @@ -221,7 +221,8 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
> return -EINVAL;
> config = ofdid->data;
>
> - wdt->ctrl = WDT_CTRL_1MHZ_CLK;
> + wdt->ctrl |= readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE;
> + wdt->ctrl |= WDT_CTRL_1MHZ_CLK;
>
> /*
> * Control reset on a per-device basis to ensure the
> @@ -243,11 +244,11 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
> if (of_property_read_bool(np, "aspeed,external-signal"))
> wdt->ctrl |= WDT_CTRL_WDT_EXT;
>
> - writel(wdt->ctrl, wdt->base + WDT_CTRL);
> -
> - if (readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE) {
> + if (wdt->ctrl & WDT_CTRL_ENABLE) {
> aspeed_wdt_start(&wdt->wdd);

Why call the start function in this case ?

> set_bit(WDOG_HW_RUNNING, &wdt->wdd.status); > + } else {
> + writel(wdt->ctrl, wdt->base + WDT_CTRL);
> }
>
> if (of_device_is_compatible(np, "aspeed,ast2500-wdt")) {
>