On Mon, 2021-08-30 at 16:43 -0500, Bjorn Helgaas wrote:
> On Mon, Aug 30, 2021 at 03:09:44PM +0800, Chuanjia Liu wrote:
> > On Fri, 2021-08-27 at 11:46 -0500, Bjorn Helgaas wrote:
> > > On Mon, Aug 23, 2021 at 11:27:56AM +0800, Chuanjia Liu wrote:
> > > > @@ -995,6 +1004,14 @@ static int mtk_pcie_subsys_powerup(struct
> > > > mtk_pcie *pcie)
> > > > return PTR_ERR(pcie->base);
> > > > }
> > > >
> > > > + cfg_node = of_find_compatible_node(NULL, NULL,
> > > > + "mediatek,generic-
> > > > pciecfg");
> > > > + if (cfg_node) {
> > > > + pcie->cfg = syscon_node_to_regmap(cfg_node);
> > >
> > > Other drivers in drivers/pci/controller/ use
> > > syscon_regmap_lookup_by_phandle() (j721e, dra7xx, keystone,
> > > layerscape, artpec6) or syscon_regmap_lookup_by_compatible()
> > > (imx6,
> > > kirin, v3-semi).
> > >
> > > You should do it the same way unless there's a need to be
> > > different.
> >
> > I have used phandle, but Rob suggested to search for the node by
> > compatible.
> > The reason why syscon_regmap_lookup_by_compatible() is not
> > used here is that the pciecfg node is optional, and there is no
> > need to
> > return error when the node is not searched.
>
> How about this?
>
> regmap = syscon_regmap_lookup_by_compatible("mediatek,generic-
> pciecfg");
> if (!IS_ERR(regmap))
> pcie->cfg = regmap;
Hi Bjorn,
We need to deal with three situations
1) No error
2) The error of the node not found, don't do anything
3) Other errors, return errors
I guess you mean
regmap = syscon_regmap_lookup_by_compatible("mediatek,generic-
pciecfg");
if (!IS_ERR(regmap))
pcie->cfg = regmap;
else if (IS_ERR(regmap) && PTR_ERR(regmap) != -ENODEV)
return PTR_ERR(regmap);
I'm not sure if we need this, it seems a little weird and there are
many drivers in other subsystems that use syscon_node_to_regmap().
Thanks
Chuanjia
