On 30/07/2024 11:52, Arend Van Spriel wrote: > On July 30, 2024 11:01:43 AM Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote: > >> On 30/07/2024 08:37, Arend Van Spriel wrote: >>> + Linus W >>> >>> On July 30, 2024 5:31:15 AM Jacobe Zang <jacobe.zang@xxxxxxxxxx> wrote: >>> >>>> Not only AP6275P Wi-Fi device but also all Broadcom wireless devices allow >>>> external low power clock input. In DTS the clock as an optional choice in >>>> the absence of an internal clock. >>>> >>>> Reviewed-by: Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx> >>>> Signed-off-by: Jacobe Zang <jacobe.zang@xxxxxxxxxx> >>>> --- >>>> .../bindings/net/wireless/brcm,bcm4329-fmac.yaml | 8 ++++++++ >>>> 1 file changed, 8 insertions(+) >>>> >>>> diff --git >>>> a/Documentation/devicetree/bindings/net/wireless/brcm,bcm4329-fmac.yaml >>>> b/Documentation/devicetree/bindings/net/wireless/brcm,bcm4329-fmac.yaml >>>> index 2c2093c77ec9a..a3607d55ef367 100644 >>>> --- a/Documentation/devicetree/bindings/net/wireless/brcm,bcm4329-fmac.yaml >>>> +++ b/Documentation/devicetree/bindings/net/wireless/brcm,bcm4329-fmac.yaml >>>> @@ -122,6 +122,14 @@ properties: >>>> NVRAM. This would normally be filled in by the bootloader from platform >>>> configuration data. >>>> >>>> + clocks: >>>> + items: >>>> + - description: External Low Power Clock input (32.768KHz) >>>> + >>>> + clock-names: >>>> + items: >>>> + - const: lpo >>>> + >>> >>> We still have an issue that this clock input is also present in the >>> bindings specification broadcom-bluetooth.yaml (not in bluetooth >>> subfolder). This clock is actually a chip resource. What happens if both >>> are defined and both wifi and bt drivers try to enable this clock? Can this >>> be expressed in yaml or can we only put a textual warning in the property >>> descriptions? >> >> Just like all clocks, what would happen? It will be enabled. > > Oh, wow! Cool stuff. But seriously is it not a problem to have two entities > controlling one and the same clock? Is this use-case taken into account by > the clock framework? Yes, it is handled correctly. That's a basic use-case, handled by CCF since some years (~12?). Anyway, whatever OS is doing (or not doing) with the clocks is independent of the bindings here. The question is about hardware - does this node, which represents PCI interface of the chip, has/uses the clocks? Best regards, Krzysztof
