On 15/01/2024 09:43, Billy Tsai wrote: >>>>> +examples: >>>>> + - | >>>>> + #include <dt-bindings/clock/aspeed-clock.h> >>>>> + pwm_tach: pwm-tach-controller@1e610000 { >>>>> + compatible = "aspeed,ast2600-pwm-tach"; >>>>> + reg = <0x1e610000 0x100>; >>>>> + clocks = <&syscon ASPEED_CLK_AHB>; >>>>> + resets = <&syscon ASPEED_RESET_PWM>; >>>>> + #pwm-cells = <3>; >>>>> + >>>>> + fan-0 { >>>>> + tach-ch = /bits/ 8 <0x0>; >>>>> + }; >>>>> + >>>>> + fan-1 { >>>>> + tach-ch = /bits/ 8 <0x1 0x2>; >>>>> + }; >>> >>>> NAK on this based on how you are using pwm-fan in v10 discussion. See my >>>> comments there. >>> >>> Okay, I will merge everything from the pwm-fan0 node into the fan-0 node >>> and add the 'simple-bus' to the compatible string of the pwm_tach node. > >> What simple-bus has anything to do with it? This is not a bus. Just to >> remind: we talk about bindings, not driver. > > Hi Krzysztof, > > If I want to create a dt-binding to indicate that the child nodes > should be treated as platform devices, which will be probed based on the probed? Bindings do not probe. You ignored: "we talk about bindings, not driver." > compatible string, can I add "simple-bus" for our pwm_tach node like the > following? No, because this is not a bus. > pwm_tach: pwm-tach-controller@1e610000 { > compatible = "aspeed,ast2600-pwm-tach", "simple-bus"; > reg = <0x1e610000 0x100>; > clocks = <&syscon ASPEED_CLK_AHB>; > resets = <&syscon ASPEED_RESET_PWM>; > #pwm-cells = <3>; > > fan-0 { > tach-ch = /bits/ 8 <0x0>; > compatible = "pwm-fan"; > pwms = <&pwm_tach 0 40000 0>; > }; > > fan-1 { > tach-ch = /bits/ 8 <0x1 0x2>; > compatible = "pwm-fan"; > pwms = <&pwm_tach 1 40000 0>; > }; > }; > Or do you have any other suggestions for describing this in the dt-bindings? There is no need to describe it in the bindings. The existing compatible describes it sufficiently. Your pwms now duplicate the tach-ch... I don't understand what you want to achieve here in terms of hardware description (again, please steer away from talking about Linux drivers and probing, it's not related). Best regards, Krzysztof