On 10/3/19 6:33 AM, Martin Hundebøll wrote:
Linux should handle when the pcf2127 watchdog feature is enabled by the
bootloader. This is done by checking the watchdog timer value during
init, and set the WDOG_HW_RUNNING flag if the value differs from zero.
Signed-off-by: Martin Hundebøll <martin@xxxxxxxxxx>
Acked-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
Change since v1:
* remove setting of WDOG_HW_RUNNING in pcf2127_wdt_start()
drivers/rtc/rtc-pcf2127.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
index cb3472f..4229915 100644
--- a/drivers/rtc/rtc-pcf2127.c
+++ b/drivers/rtc/rtc-pcf2127.c
@@ -420,6 +420,7 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
const char *name, bool has_nvmem)
{
struct pcf2127 *pcf2127;
+ u32 wdd_timeout;
int ret = 0;
dev_dbg(dev, "%s\n", __func__);
@@ -462,7 +463,6 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
/*
* Watchdog timer enabled and reset pin /RST activated when timed out.
* Select 1Hz clock source for watchdog timer.
- * Timer is not started until WD_VAL is loaded with a valid value.
* Note: Countdown timer disabled and not available.
*/
ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_WD_CTL,
@@ -478,6 +478,16 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
return ret;
}
+ /* Test if watchdog timer is started by bootloader */
+ ret = regmap_read(pcf2127->regmap, PCF2127_REG_WD_VAL, &wdd_timeout);
+ if (ret) {
+ dev_err(dev, "%s: watchdog value (wd_wal) failed\n", __func__);
+ return ret;
+ }
+
+ if (wdd_timeout)
+ set_bit(WDOG_HW_RUNNING, &pcf2127->wdd.status);
+
ret = devm_watchdog_register_device(dev, &pcf2127->wdd);
if (ret)
return ret;