Am Montag, 15. Juli 2024, 20:01:35 CEST schrieb Dragan Simic: > On 2024-07-15 19:46, Heiko Stübner wrote: > > Am Montag, 15. Juli 2024, 17:15:45 CEST schrieb Dragan Simic: > >> On 2024-07-15 13:02, Heiko Stuebner wrote: > >> > In contrast to fixed clocks that are described as ungateable, boards > >> > sometimes use additional oscillators for things like PCIe reference > >> > clocks, that need actual supplies to get enabled and enable-gpios to be > >> > toggled for them to work. > >> > > >> > This adds a binding for such oscillators that are not configurable > >> > themself, but need to handle supplies for them to work. > >> > > >> > In schematics they often can be seen as > >> > > >> > ---------------- > >> > Enable - | 100MHz,3.3V, | - VDD > >> > | 3225 | > >> > GND - | | - OUT > >> > ---------------- > >> > > >> > or similar. The enable pin might be separate but can also just be tied > >> > to the vdd supply, hence it is optional in the binding. > >> > > >> > Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx> > >> > --- > >> > .../bindings/clock/voltage-oscillator.yaml | 49 +++++++++++++++++++ > >> > 1 file changed, 49 insertions(+) > >> > create mode 100644 > >> > Documentation/devicetree/bindings/clock/voltage-oscillator.yaml > >> > > >> > diff --git > >> > a/Documentation/devicetree/bindings/clock/voltage-oscillator.yaml > >> > b/Documentation/devicetree/bindings/clock/voltage-oscillator.yaml > >> > new file mode 100644 > >> > index 0000000000000..8bff6b0fd582e > >> > --- /dev/null > >> > +++ b/Documentation/devicetree/bindings/clock/voltage-oscillator.yaml > >> > @@ -0,0 +1,49 @@ > >> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > >> > +%YAML 1.2 > >> > +--- > >> > +$id: http://devicetree.org/schemas/clock/voltage-oscillator.yaml# > >> > +$schema: http://devicetree.org/meta-schemas/core.yaml# > >> > + > >> > +title: Voltage controlled oscillator > >> > >> Frankly, I find the "voltage-oscillator" and "voltage controlled > >> oscillator" names awkward. In general, "clock" is used throughout > >> the entire kernel, when it comes to naming files and defining > >> "compatible" strings. Thus, I'd suggest that "clock" is used here > >> instead of "oscillator", because it's consistent and shorter. > >> > >> How about using "gated-clock" for the "compatible" string, and > >> "Simple gated clock generator" instead of "voltage controlled > >> oscillator"? Besides sounding awkward, "voltage controlled > >> oscillator" may suggest that the clock generator can be adjusted > >> or programmed somehow by applying the voltage, while it can only > >> be enabled or disabled that way, which is by definition clock > >> gating. Thus, "gated-clock" and "Simple gated clock generator" > >> would fit very well. > > > > The naming came from Stephen - one of the clock maintainers ;-) > > See discussion in v1. Who also described these things as > > "voltage-controlled-oscillators". > > > > And from that discussion I also got the impression we should aim for > > more specific naming - especially when talking about dt-bindings, for > > this > > "usage in the Linux kernel" actually isn't a suitable metric and > > "gated-clock" is probably way too generic I think. > > I see, thanks for the clarification. Though, the generic nature of > "gated-clock" as the name may actually make this driver a bit more > future-proof, by allowing some other features to be added to it at > some point in the future, avoiding that way the need for yet another > kernel driver. you're talking about the driver ... we're in the hardware-binding here. Those are two completely different topics ;-) . Devicetree is always about describing the hardware as best as possible, so you don't want too many "generics" there, because we're always talking about specific ICs soldered to some board. I also "violated" that in my v1 by grouping in the the Diodes parts, which as Stephen pointed out are quite different afterall. Heiko
