[PATCH v2] watchdog: w83627hf_wdt: add bootstatus support

[Henning Schild]

The status bit in the status and control register can tell us whether
the last reboot was caused by the watchdog. Make sure to take that into
the bootstatus before clearing it.

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Henning Schild <henning.schild@xxxxxxxxxxx>
---
 drivers/watchdog/w83627hf_wdt.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/watchdog/w83627hf_wdt.c b/drivers/watchdog/w83627hf_wdt.c
index 56a4a4030ca9..bc33b63c5a5d 100644
--- a/drivers/watchdog/w83627hf_wdt.c
+++ b/drivers/watchdog/w83627hf_wdt.c
@@ -113,6 +113,10 @@ MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");
 #define W836X7HF_WDT_CSR	0xf7
 #define NCT6102D_WDT_CSR	0xf2
 
+#define WDT_CSR_STATUS		0x10
+#define WDT_CSR_KBD		0x40
+#define WDT_CSR_MOUSE		0x80
+
 static void superio_outb(int reg, int val)
 {
 	outb(reg, WDT_EFER);
@@ -244,8 +248,12 @@ static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
 	t = superio_inb(cr_wdt_control) & ~0x0C;
 	superio_outb(cr_wdt_control, t);
 
-	/* reset trigger, disable keyboard & mouse turning off watchdog */
-	t = superio_inb(cr_wdt_csr) & ~0xD0;
+	t = superio_inb(cr_wdt_csr);
+	if (t & WDT_CSR_STATUS)
+		wdog->bootstatus |= WDIOF_CARDRESET;
+
+	/* reset status, disable keyboard & mouse turning off watchdog */
+	t &= ~(WDT_CSR_STATUS | WDT_CSR_KBD | WDT_CSR_MOUSE);
 	superio_outb(cr_wdt_csr, t);
 
 	superio_exit();
-- 
2.35.1