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authorAndrew Jeffery <andrew@aj.id.au>2017-09-20 15:00:17 +0930
committerWim Van Sebroeck <wim@iguana.be>2017-12-28 20:44:48 +0100
commit9f3e13c74e1b4f370c3de06cb504c003091c9673 (patch)
treefbd78134e88a095eb1e8667a3dbe2e55388bb7d9
parentbe17980d9be5a5c1ece83836b24fabce648b92aa (diff)
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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 <andrew@aj.id.au> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
-rw-r--r--drivers/watchdog/aspeed_wdt.c8
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index 79cc766cd30f..6c6dd3f4c48d 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);
}