On 2/1/2024 4:03 PM, Bjorn Andersson wrote: > On Wed, Jan 31, 2024 at 12:04:14PM +0100, Bartosz Golaszewski wrote: >> On Tue, Jan 30, 2024 at 10:54 PM Bjorn Andersson <andersson@xxxxxxxxxx> wrote: >>> >>> On Thu, Jan 18, 2024 at 12:15:27PM +0100, Greg Kroah-Hartman wrote: >>>> On Thu, Jan 18, 2024 at 11:58:50AM +0100, Bartosz Golaszewski wrote: >>>>> On Wed, Jan 17, 2024 at 5:45 PM Greg Kroah-Hartman >>>>> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: >>>>>> >>>>>> On Wed, Jan 17, 2024 at 05:07:43PM +0100, Bartosz Golaszewski wrote: >>>>>>> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> >>>>>>> >>>>>>> In order to introduce PCI power-sequencing, we need to create platform >>>>>>> devices for child nodes of the port node. >>>>>> >>>>>> Ick, why a platform device? What is the parent of this device, a PCI >>>>>> device? If so, then this can't be a platform device, as that's not what >>>>>> it is, it's something else so make it a device of that type,. >>>>>> >>>>> >>>>> Greg, >>>>> >>>>> This is literally what we agreed on at LPC. In fact: during one of the >>>>> hall track discussions I said that you typically NAK any attempts at >>>>> using the platform bus for "fake" devices but you responded that this >>>>> is what the USB on-board HUB does and while it's not pretty, this is >>>>> what we need to do. >>>> >>>> Ah, you need to remind me of these things, this changelog was pretty >>>> sparse :) >>>> >>> >>> I believe I missed this part of the discussion, why does this need to be >>> a platform_device? What does the platform_bus bring that can't be >>> provided by some other bus? >>> >> >> Does it need to be a platform_device? No, of course not. Does it make >> sense for it to be one? Yes, for two reasons: >> >> 1. The ATH11K WLAN module is represented on the device tree like a >> platform device, we know it's always there and it consumes regulators >> from another platform device. The fact it uses PCIe doesn't change the >> fact that it is logically a platform device. > > Are you referring to the ath11k SNOC (firmware running on co-processor > in the SoC) variant? > > Afaict the PCIe-attached ath11k is not represented as a platform_device > in DeviceTree. Are you considering out-of-tree drivers? My understanding is that there are different PCIe modules, ones that don't have GPIO-control for x86 and ones that do have GPIO-control for ARM. The out-of-tree cnss platform driver used for Android has a large amount of DT control <https://git.codelinaro.org/clo/la/platform/vendor/qcom-opensource/wlan/platform/-/blob/wlan-platform.lnx.1.0.r1-rel/cnss2/power.c?ref_type=heads> (not sure off hand where the DT files themselves are) /jeff
