On Thu, 04 Apr 2019, Vaittinen, Matti wrote: > Hello Alexandre, > > On Thu, 2019-04-04 at 09:56 +0200, Alexandre Belloni wrote: > > On 04/04/2019 10:24:49+0300, Matti Vaittinen wrote: > > > On Thu, Apr 04, 2019 at 07:54:52AM +0100, Lee Jones wrote: > > > > On Thu, 04 Apr 2019, Vaittinen, Matti wrote: > > > > > > > > > Actually, now that I thik of it the right way to do this would > > > > > have > > > > > been the function pointer in parent data as was done in > > > > > original patch > > > > > set. HW-colleagues tend to re-use HW blocks, and we like to re- > > > > > use our > > > > > drivers. If the next PMIC from ROHM uses same RTC block but > > > > > does not > > > > > provide watchdog - then it is cleanest solution to fall back to > > > > > function pointer and leave it to NULL when there is no WDT or > > > > > when WDT > > > > > is unused. Another option is to export dummy function - which > > > > > is not so > > > > > nice. > > > > > > > > I think the converse is true. > > > > > > > > Pointers to functions outside of a subsystem API context are > > > > generally > > > > horrible. It's much nicer to call a function which can be easily > > > > stubbed out in a header file based on a Kconfig option. It's how > > > > most > > > > kernel APIs work. > > > > > > I hate to admit but I see your point. This nicely solves any issues > > > in > > > syncronizing the startup for driver providing function pointer and > > > for > > > driver using it. > > > > > > > Wouldn't it be easier to register the watchdog driver as part of the > > RTC > > driver? > > > > As I see it, the wdt is just a glorified RTC alarm. > > Do you suggest me to put all the stuff now placed in > drivers/watchdog/bd70528_wdt.c into rtc driver? It would be doable - > but I'd rather kept the WDT independent module so that it can be left > out of config if WDT needs not to be used. And same with RTC. Also, re- > use of RTC driver in HW which does not include WDT is easier when WDT > is a separate module. To me it looks much cleaner to have the WDT as > own module than polluting the RTC driver with config ifdefs. I haven't looked at the code, but I agree with this in principle. I'm a firm believer of having functionality in the most appropriate subsystem. IMHO, if a device can be neatly split 9/10 it should be. > But from HW perspective you are correct. The WDT in BD70528 seems to be > kind of RTC alarm which shuts of the PMIC if triggered. > > Br, > Matti Vaittinen -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog
