From: Andrew Jeffery Date: Wed, 20 Sep 2017 05:30:17 +0000 (+0930) Subject: watchdog: aspeed: Retain watchdog enabled state X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=9f3e13c74e1b4f370c3de06cb504c003091c9673;p=linux.git watchdog: aspeed: Retain watchdog enabled state An unintended post-condition of probe() is that the watchdog is disabled. This behaviour was introduced by an unnecessary write to the control register to configure the hardware based on the devicetree. The write is unnecessary because the cached control value that is manipulated by the code parsing the devicetree is eventually written by aspeed_wdt_enable(), which is when we care how the control register should be configured. Remove the write to restore expected behaviour. Fixes: b7f0b8ad25f3 ("drivers/watchdog: ASPEED reference dev tree properties for config") Signed-off-by: Andrew Jeffery Reviewed-by: Joel Stanley Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c index 79cc766cd30fd..6c6dd3f4c48d2 100644 --- a/drivers/watchdog/aspeed_wdt.c +++ b/drivers/watchdog/aspeed_wdt.c @@ -243,9 +243,13 @@ 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) { + /* + * The watchdog is running, but invoke aspeed_wdt_start() to + * write wdt->ctrl to WDT_CTRL to ensure the watchdog's + * configuration conforms to the driver's expectations. + * Primarily, ensure we're using the 1MHz clock source. + */ aspeed_wdt_start(&wdt->wdd); set_bit(WDOG_HW_RUNNING, &wdt->wdd.status); }