On 11/10/2022 15:23, Biju Das wrote: >> Subject: Re: [PATCH v4 1/4] dt-bindings: mfd: Document RZ/G2L MTU3a >> bindings >> >> On 11/10/2022 10:55, Biju Das wrote: >>> >>>>> .../bindings/mfd/renesas,rz-mtu3.yaml | 305 >>>> ++++++++++++++++++ >>>>> 1 file changed, 305 insertions(+) >>>>> create mode 100644 >>>>> Documentation/devicetree/bindings/mfd/renesas,rz-mtu3.yaml >>>> >>>> This should not be in MFD. Just because some device has few >> features, >>>> does not mean it should go to MFD... Choose either timer or pwm. >>> >>> MFD is for multifunction device. This IP supports multiple functions >>> like timer, pwm, clock source/events. That is the reason I have >> added >>> here. MFD is core which provides register access for client devices. >>> >>> For me moving it to pwm or counter is not a big problem. >>> Why do you think it cannot be MFD? >> >> >> Because it makes MFD a dump for everything where author did not want >> to think about real device aspects, but instead represented driver >> design (MFD driver). > > Core driver is MFD, just provides resources to child devices > and is not aware of any real device aspects. > >> >> MFDs are pretty often combining unrelated features, e.g. PMICs which >> have wakeup and system power control, regulator, 32 kHz clocks, RTC >> and some USB connector. > > Here also same right? pwm, counter and clock are 3 unrelated features. > That is the reason we have separate subsystems for these features. These are quite similar features of a similar piece of hardware. Sometimes called timer. > >> >> Just because you will have clocksource driver, PWM driver and timer >> driver does not make it a MFD. > > MFD is multi function device. No. MFD is a Linux subsystem name. Not a device type. The bindings are located in respective type. > So are are you agreeing Clock source, PWM and > timer are different functionalities or not? If not, why do we have 3 subsystems, > if it is same? Linux subsystems? We can have millions of them and it is not related to bindings. > Where do keep these bindings as there is only single "rz_mtu" bindings for these 3 different functionalities? Again, focus on hardware not on Linux drivers. Hardware is called MTU - Multi-Function TIMER Unit. Timer. > pwm or counter or mfd? Not MFD. I already proposed where to put it. Other Timer/PWM/Counter units are also in timer. Renesas is not special to get some exceptions. Best regards, Krzysztof
