The current set_timeout() handling can't change the timeout value if the watchdog is already running because the watchdog must be disabled before a new timeout value can be set. This sounds a bit strange but it is the only way to change the timeout value. The watchdog also has a second quirk. The timeout value combines the timeout and the watchdog enable signal. So a value not equal zero indicates that the watchdog is running. This leads into problems if the watchdog is disabled and a new timeout value should be set because during setting the timeout value the watchdog gets enabled. The driver must check if the watchdog is disabled. In that case the timeout value must be stored to be available for the later wdt_start() call. If the watchdog is already running the driver must write the new timeout value immediately to the watchdog. There was also a issue during the driver probe sequence. The driver must set a new timeout reference mark if the watchdog was enabled in a earlier stage e.g. the bootloader. Changelog: v8: - make use of watchdog_active() helper instead of watchdog_hw_running() - fix misspellings - drop set HW_RUNNING flag during wdt_start() introduced with v6 - call _da9063_wdt_set_timeout() during probe() directly if watchdog is running. - da9063_wdt_is_running() returns now the raw timeout regval instead of the maped timeout in seconds. - fix da9063_wdt_is_running() return value, use unsigned int instead of int. v7: - reorder patch stack "Fixes:" patches first. v6: - fix timeout value buffering (don't buffer it twice, use HW_RUNNING flag) - set HW_RUNNING flag during wdt_start() - add watchdog enable check during probe() - rename _da9063_wdt_set_timeout -> da9063_wdt_update_timeout v5: - add buffering the timeout if the watchdog is disabled - add more comments v4: - Fix patch description v3: - add delay between disable watchdog and write new timeout value during timeout update - fix comment to be more common v2: - style changes v1: - initial commit Marco Felsch (4): watchdog: da9063: Fix setting/changing timeout watchdog: da9063: Fix updating timeout value watchdog: da9063: Fix timeout handling during probe watchdog: da9063: rename helper function to avoid misunderstandings drivers/watchdog/da9063_wdt.c | 67 +++++++++++++++++++++++++++++++---- 1 file changed, 61 insertions(+), 6 deletions(-) -- 2.17.0 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
