Re: [PATCH v10 0/7] PCI: brcmstb: root port turns on sub-device power

On Thu, Dec 09, 2021 at 04:13:58PM -0500, Jim Quinlan wrote:

v10 -- Bindings commit example: in comment, refer to bridge under
       controller node as a root port. (Pali)
    -- Bindings commit example: remove three properties that are not
       appropriate for a PCIe endpoint node. (Rob)

v9  -- Simplify where this mechanism works: instead of looking for
       regulators below every bridge, just look for them at the
       bridge under the root bus (root port).  Now there is no
       modification of portdrv_{pci,core}.c in this submission.
    -- Although Pali is working on support for probing native
       PCIe controller drivers, this work may take some time to
       implement and it still might not be able to accomodate
       our driver's requirements (e.g. vreg suspend/resume control).
    -- Move regulator suspend/resume control to Brcm RC driver.  It
       must reside there because (a) in order to know when to
       initiate linkup during resume and (b) to turn on the
       regulators before any config-space accesses occur.

You now have a mixture of 'generic' add/remove_bus hooks and the host 
controller suspend/resume managing the regulators. I think long term, 
the portdrv is going to be the right place for all of this with some 
interface defined for link control. So I think this solution moves 
sideways rather than towards anything common.

Unfortunately, the only leverage maintainers have to get folks to care 
about any refactoring is to reject features. We're lucky to find anyone 
to test refactoring when posted if done independently. There's a long 
list of commits of PCI hosts that I've broken to prove that. So it's 
up to Lorenzo and Bjorn on what they want to do here.

Rob

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