On Fri, Dec 11, 2020 at 5:10 PM Rasmus Villemoes <rasmus.villemoes@xxxxxxxxx> wrote: > > On 11/12/2020 23.30, Rob Herring wrote: > > On Fri, Dec 11, 2020 at 3:56 PM Rasmus Villemoes > > <rasmus.villemoes@xxxxxxxxx> wrote: > >> > >> Some RTCs, e.g. the pcf2127, can be used as a hardware watchdog. But > >> if the reset pin is not actually wired up, the driver exposes a > >> watchdog device that doesn't actually work. > >> > >> Provide a standard binding that can be used to indicate that a given > >> RTC can perform a reset of the machine, similar to wakeup-source. > > > > Why not use the watchdog 'timeout-sec' property? > > Wouldn't that be overloading that property? AFAIU, that is used to ask > the kernel to program an initial timeout value into the watchdog device. > But what if one doesn't want to start the watchdog device at kernel > boot, but just indicate that the RTC has that capability? Yeah, I guess you're right. > It's quite possible that if it can act as a watchdog device (and > has-watchdog was also suggested), one would also want timeout-sec and > other watchdog bindings to apply. But that can be added later, by those > who actually want that. > > For now, I'd really like to get my board booting again (or rather, not > get reset by the real watchdog just because the pcf2127 driver now > exposes something as /dev/wathdog0, pushing the real one to > /dev/wathcdog1 which doesn't get pinged from userspace). I'm wondering how you solve which wdog to ping when there are multiple without relying on numbering. I guess 'reset-source' will solve that even if that's not your current fix. So I guess I'm fine with this. But you need to send to the DT list so checks are run. Rob
