Re: [RFC 8/9] PCI/pwrseq: add a pwrseq driver for QCA6390

[Arnd Bergmann]

On Tue, Jan 9, 2024, at 11:09, Kalle Valo wrote:
> Chen-Yu Tsai <wenst@xxxxxxxxxxxx> writes:
>> On Tue, Jan 9, 2024 at 5:18 PM Kalle Valo <kvalo@xxxxxxxxxx> wrote:
>>> Jeff Johnson <quic_jjohnson@xxxxxxxxxxx> writes:
>>>
>>> > On 1/4/2024 5:01 AM, Bartosz Golaszewski wrote:
>>> >> diff --git a/drivers/pci/pcie/pwrseq/Kconfig b/drivers/pci/pcie/pwrseq/Kconfig
>>> >> index 010e31f432c9..f9fe555b8506 100644
>>> >> --- a/drivers/pci/pcie/pwrseq/Kconfig
>>> >> +++ b/drivers/pci/pcie/pwrseq/Kconfig
>>> >> @@ -6,3 +6,14 @@ menuconfig PCIE_PWRSEQ
>>> >>      help
>>> >>        Say yes here to enable support for PCIe power sequencing
>>> >>        drivers.
>>> >> +
>>> >> +if PCIE_PWRSEQ
>>> >> +
>>> >> +config PCIE_PWRSEQ_QCA6390
>>> >> +    tristate "PCIe Power Sequencing driver for QCA6390"
>>> >> +    depends on ARCH_QCOM || COMPILE_TEST
>>> >> +    help
>>> >> +      Enable support for the PCIe power sequencing driver for the
>>> >> +      ath11k module of the QCA6390 WLAN/BT chip.
>>> >> +
>>> >> +endif
>>> >
>>> > As I mentioned in the 5/9 patch I'm concerned that the current
>>> > definition of PCIE_PWRSEQ and PCIE_PWRSEQ_QCA6390 will effectively hide
>>> > the fact that QCA6390 may need additional configuration since the menu
>>> > item will only show up if you have already enabled PCIE_PWRSEQ.
>>> > Yes I see that these are set in the defconfig in 9/9 but I'm concerned
>>> > about the more generic case.
>>> >
>>> > I'm wondering if there should be a separate config QCA6390 within ath11k
>>> > which would then select PCIE_PWRSEQ and PCIE_PWRSEQ_QCA6390
>>>
>>> Or is it possible to provide an optional dependency in Kconfig (I guess
>>
>> imply PCIE_PWRSEQ
>> imply PCIE_PWRSEQ_QCA6390
>> ?
>
> Nice, I had forgotten imply altogether. Would 'imply
> PCIE_PWRSEQ_QCA6390' in ath11k Kconfig be enough to address Jeff's
> concern?

Please don't use imply (ever), it doesn't normally do
what you want. In this case, the only effect the
'imply' has is to change the default of the PCIE_PWRSEQ_QCA6390
option when a defconfig contains QCA6390.

If this is indeed what you want, it's still better to do the
equivalent expression in PCIE_PWRSEQ_QCA6390 rather than ATH11K:

config PCIE_PWRSEQ_QCA6390
      tristate "PCIe Power Sequencing driver for QCA6390"
      default ATH11K && ARCH_QCOM

      Arnd