From a147720dc69196b45f60c450efe609939d08f0dc Mon Sep 17 00:00:00 2001 From: Gregory Oakes Date: Thu, 16 Mar 2023 15:13:12 -0500 Subject: [PATCH] watchdog: sp5100_tco: Immediately trigger upon starting. commit 4eda19cc8a29cde3580ed73bf11dc73b4e757697 upstream. The watchdog countdown is supposed to begin when the device file is opened. Instead, it would begin countdown upon the first write to or close of the device file. Now, the ping operation is called within the start operation which ensures the countdown begins. From experimenation, it does not appear possible to do this with a single write including both the start bit and the trigger bit. So, it is done as two distinct writes. Signed-off-by: Gregory Oakes Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20230316201312.17538-1-gregory.oakes@amd.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Cc: Mario Limonciello Signed-off-by: Greg Kroah-Hartman --- drivers/watchdog/sp5100_tco.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c index fb426b7d81dac..14f8d8d90920f 100644 --- a/drivers/watchdog/sp5100_tco.c +++ b/drivers/watchdog/sp5100_tco.c @@ -115,6 +115,10 @@ static int tco_timer_start(struct watchdog_device *wdd) val |= SP5100_WDT_START_STOP_BIT; writel(val, SP5100_WDT_CONTROL(tco->tcobase)); + /* This must be a distinct write. */ + val |= SP5100_WDT_TRIGGER_BIT; + writel(val, SP5100_WDT_CONTROL(tco->tcobase)); + return 0; } -- 2.39.5