[PATCH v7 0/8] PCI: Enable Power and configure the TC9563 PCIe switch

Dmitry Baryshkov dmitry.baryshkov at oss.qualcomm.com
Wed Oct 29 17:07:49 PDT 2025


On Wed, Oct 29, 2025 at 06:23:23PM -0500, Bjorn Helgaas wrote:
> On Wed, Oct 29, 2025 at 04:59:53PM +0530, Krishna Chaitanya Chundru wrote:
> > TC9563 is the PCIe switch which has one upstream and three downstream
> > ports. To one of the downstream ports ethernet MAC is connected as endpoint
> > device. Other two downstream ports are supposed to connect to external
> > device. One Host can connect to TC956x by upstream port.
> > 
> > TC9563 switch power is controlled by the GPIO's. After powering on
> > the switch will immediately participate in the link training. if the
> > host is also ready by that time PCIe link will established. 
> > 
> > The TC9563 needs to configured certain parameters like de-emphasis,
> > disable unused port etc before link is established.
> > 
> > As the controller starts link training before the probe of pwrctl driver,
> > the PCIe link may come up as soon as we power on the switch. Due to this
> > configuring the switch itself through i2c will not have any effect as
> > this configuration needs to done before link training. To avoid this
> > introduce two functions in pci_ops to start_link() & stop_link() which
> > will disable the link training if the PCIe link is not up yet.
> > 
> > This series depends on the https://lore.kernel.org/all/20250124101038.3871768-3-krishna.chundru@oss.qualcomm.com/
> 
> What does this series apply to?  It doesn't apply cleanly to v6.18-rc1
> (the normal base for topic branches) or v6.18-rc3 or pci/next.

Juding by the base-commit in the cover letter, it is the following tree:

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=e53642b87a4f4b03a8d7e5f8507fc3cd0c595ea6

Merge tag 'v6.18-rc3-smb-server-fixes' of git://git.samba.org/ksmbd

Not that I have an idea, _why_ that tree was used, was it really used or
why there are no dependencies mentioned in the footer of the cover
letter.

> 
> I tried first applying the patches from
> https://lore.kernel.org/all/20250124101038.3871768-3-krishna.chundru@oss.qualcomm.com/,
> but those don't apply to -rc1 or -rc3 either.
> 
> Bjorn

-- 
With best wishes
Dmitry



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