Re: [PATCH 3/4] PCI: cadence-ep: Introduce cdns_pcie_ep_disable helper for cleanup

[Siddharth Vadapalli]

On Tue, Mar 18, 2025 at 01:33:04PM +0530, Manivannan Sadhasivam wrote:

Hello Mani,

> On Fri, Mar 07, 2025 at 04:01:27PM +0530, Siddharth Vadapalli wrote:
> > Introduce the helper function cdns_pcie_ep_disable() which will undo the
> > configuration performed by cdns_pcie_ep_setup(). Also, export it for use
> > by the existing callers of cdns_pcie_ep_setup(), thereby allowing them
> > to cleanup on their exit path.
> > 
> > Signed-off-by: Siddharth Vadapalli <s-vadapalli@xxxxxx>
> > ---
> >  drivers/pci/controller/cadence/pcie-cadence-ep.c | 10 ++++++++++
> >  drivers/pci/controller/cadence/pcie-cadence.h    |  5 +++++
> >  2 files changed, 15 insertions(+)
> > 
> > diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
> > index eeb2afdd223e..85bec57fa5d9 100644
> > --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
> > +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
> > @@ -646,6 +646,16 @@ static const struct pci_epc_ops cdns_pcie_epc_ops = {
> >  	.get_features	= cdns_pcie_ep_get_features,
> >  };
> >  
> > +void cdns_pcie_ep_disable(struct cdns_pcie_ep *ep)
> > +{
> > +	struct device *dev = ep->pcie.dev;
> > +	struct pci_epc *epc = to_pci_epc(dev);
> > +
> 
> pci_epc_deinit_notify()

I had initially planned to add this, but I noticed that it is not
invoked by dw_pcie_ep_deinit() within
drivers/pci/controller/dwc/pcie-designware-ep.c
Since cdns_pcie_ep_disable() is similar to dw_pcie_ep_deinit(), I
decided to drop it. Current callers of pci_epc_deinit_notify() are:
drivers/pci/controller/dwc/pcie-qcom-ep.c
drivers/pci/controller/dwc/pcie-tegra194.c
while there are many more users of dw_pcie_ep_deinit() that don't invoke
pci_epc_deinit_notify().

While I don't intend to justify dropping pci_epc_deinit_notify() in the
cleanup path, I wanted to check if this should be added to
dw_pcie_ep_deinit() as well. Or is it the case that dw_pcie_ep_deinit()
is different from cdns_pcie_ep_disable()? Please let me know.

Regards,
Siddharth.