[PATCH v6 0/7] PCI: mediatek-gen3: add power control support

[Chen-Yu Tsai]

On Tue, Mar 24, 2026 at 4:01 PM Manivannan Sadhasivam <mani at kernel.org> wrote:
>
> On Tue, Mar 24, 2026 at 03:52:33PM +0800, Chen-Yu Tsai wrote:
> > On Tue, Mar 24, 2026 at 3:44 PM Manivannan Sadhasivam <mani at kernel.org> wrote:
> > >
> > > On Tue, Mar 24, 2026 at 01:19:52PM +0800, Chen-Yu Tsai wrote:
> > > > Hi folks,
> > > >
> > > > This is v6 of my MediaTek PCIe gen3 controller driver power control
> > > > support series. This series is based on next-20260323, with the
> > > > commit a2b2ca0c2477 ("Merge branch 'pci/controller/mediatek-gen3'")
> > > > reverted to drop the older version.
> > > >
> > > > This series is ready to be merged. Please drop the older version and use
> > > > this one instead.
> > > >
> > > > Changes since v5:
> > > > - Link to v5: https://lore.kernel.org/all/20260311075223.3303497-1-wenst@chromium.org/
> > > > - Adapt to PCI_PWRCTRL_SLOT -> PCI_PWRCTRL_GENERIC Kconfig symbol name change
> > > >
> > > > Changes since v4:
> > > > - Link to v4: https://lore.kernel.org/all/20260310091947.2742004-1-wenst@chromium.org/
> > > > - Patch 1
> > > >   - Expanded tabs in commit message
> > > > - Patch 5
> > > >   - s/mtk_pcie_device_power_(up|down)/mtk_pcie_devices_power_(up|down)/
> > > > - Patch 6
> > > >   - Adapted to mtk_pcie_devices_power_down() name change
> > > > - Patch 7
> > > >   - Fixed label typo causing build break
> > > >   - Replaced "exploded" with "populated" in commit message, and added
> > > >     more explanation about what "populated onto the mainboard" means.
> > > >
> > > > Changes since v3:
> > > > - Link to v3: https://lore.kernel.org/all/20260302053109.1117091-1-wenst@chromium.org/
> > > > - Added two patches to move kernel setup code before controller setup
> > > >   code, and controller setup code before device setup code, as requested
> > > >   by Bjorn
> > > > - Dropped dts patches as they are already merged
> > > >
> > > > I kept all the existing reviewed-by tags, since the changes to the
> > > > existing patches aren't that big.
> > > >
> > > > Changes since v2:
> > > > - Link to v2: https://lore.kernel.org/all/20260226092234.3859740-1-wenst@chromium.org/
> > > > - Made PCIE_MEDIATEK_GEN3 select PCI_PWRCTRL_SLOT, following existing
> > > >   examples
> > > >
> > > > I do wonder why the existing ones don't select PCI_PWRCTRL instead.
> > > > As there are multiple providers, and now even the M.2 power sequencing
> > > > driver, I think either we enable the common ones by default, or let
> > > > the user pick and choose.
> > > >
> > >
> > > I agree with you. I've sent a patch [1] to select these drivers in defconfig to
> > > make the users life easier. But in the meantime, let's have this dependency
> > > as-is, otherwise, until my defconfig patch lands, there is no guarantee that
> > > these drivers will get selected by default.
> >
> > I would probably just make PCI_PWRCTRL_GENERIC default m or y.
> >
> > Or make CONFIG_PCI (and probably CONFIG_USB later on) imply
> > CONFIG_POWER_SEQUENCING_PCIE_M2.
> >
>
> The problem is, these drivers are mostly targeted for DT systems as of now. If
> we select it by default for all archs, it will bloat the image size for other
> archs that don't need these drivers. That's why I wanted to enable these in arch
> defconfig.

How about

    imply CONFIG_POWER_SEQUENCING_PCIE_M2 if OF