From dff700fa81938d8947c86b7909920e5e5f772afc Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Sat, 9 Jun 2018 08:43:13 +0200 Subject: [PATCH] rtc: stmp3xxx: Don't reset the rtc in .probe() when watchdog is running MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As pointed out in the added comment resetting the rtc also stops the included watchdog. This is bad if the bootloader started the watchdog to secure the boot process. So don't reset if the watchdog is running. Signed-off-by: Uwe Kleine-König Acked-by: Guenter Roeck Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-stmp3xxx.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index d578e40d5a50..b76318fd5bb0 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -288,10 +288,22 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) platform_set_drvdata(pdev, rtc_data); - err = stmp_reset_block(rtc_data->io); - if (err) { - dev_err(&pdev->dev, "stmp_reset_block failed: %d\n", err); - return err; + /* + * Resetting the rtc stops the watchdog timer that is potentially + * running. So (assuming it is running on purpose) don't reset if the + * watchdog is enabled. + */ + if (readl(rtc_data->io + STMP3XXX_RTC_CTRL) & + STMP3XXX_RTC_CTRL_WATCHDOGEN) { + dev_info(&pdev->dev, + "Watchdog is running, skip resetting rtc\n"); + } else { + err = stmp_reset_block(rtc_data->io); + if (err) { + dev_err(&pdev->dev, "stmp_reset_block failed: %d\n", + err); + return err; + } } /*