[PATCH] watchdog: wdat_wdt: Avoid unimplemented get_timeleft

From: Thomas Weißschuh
Date: Thu Dec 22 2022 - 18:43:45 EST


As per the specification the action QUERY_COUNTDOWN_PERIOD is optional.
If the action is not implemented by the physical device the driver would
always report "0" from get_timeleft().
Avoid confusing userspace by only providing get_timeleft() when
implemented by the hardware.

Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
drivers/watchdog/wdat_wdt.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/watchdog/wdat_wdt.c b/drivers/watchdog/wdat_wdt.c
index ce7a4a9e4b03..0ba99bed59fc 100644
--- a/drivers/watchdog/wdat_wdt.c
+++ b/drivers/watchdog/wdat_wdt.c
@@ -301,13 +301,12 @@ static const struct watchdog_info wdat_wdt_info = {
.identity = "wdat_wdt",
};

-static const struct watchdog_ops wdat_wdt_ops = {
+static struct watchdog_ops wdat_wdt_ops = {
.owner = THIS_MODULE,
.start = wdat_wdt_start,
.stop = wdat_wdt_stop,
.ping = wdat_wdt_ping,
.set_timeout = wdat_wdt_set_timeout,
- .get_timeleft = wdat_wdt_get_timeleft,
};

static int wdat_wdt_probe(struct platform_device *pdev)
@@ -436,6 +435,9 @@ static int wdat_wdt_probe(struct platform_device *pdev)
list_add_tail(&instr->node, instructions);
}

+ if (wdat->instructions[ACPI_WDAT_GET_CURRENT_COUNTDOWN])
+ wdat_wdt_ops.get_timeleft = wdat_wdt_get_timeleft;
+
wdat_wdt_boot_status(wdat);
wdat_wdt_set_running(wdat);


---
base-commit: 0a924817d2ed9396401e0557c6134276d2e26382
change-id: 20221221-wdat_wdt-timeleft-b38d0db39d9f

Best regards,
--
Thomas Weißschuh <linux@xxxxxxxxxxxxxx>