Re: [PATCH v8 2/5] PCI: dwc: rockchip: reset core at driver probe

From: Peter Geis
Date: Tue Apr 26 2022 - 08:18:50 EST


On Mon, Apr 25, 2022 at 5:20 AM Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> wrote:
>
> Hi Peter,
>
> On Sa, 2022-04-23 at 11:24 -0400, Peter Geis wrote:
> > The PCIe controller is in an unknown state at driver probe. This can
> > lead to undesireable effects when the driver attempts to configure the
> > controller.
> >
> > Prevent issues in the future by resetting the core during probe.
> >
> > Signed-off-by: Peter Geis <pgwipeout@xxxxxxxxx>
> > ---
> > drivers/pci/controller/dwc/pcie-dw-rockchip.c | 22 +++++++------------
> > 1 file changed, 8 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> > index c9b341e55cbb..d67ed811e752 100644
> > --- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> > +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> > @@ -152,7 +152,13 @@ static int rockchip_pcie_resource_get(struct platform_device *pdev,
> > if (IS_ERR(rockchip->rst_gpio))
> > return PTR_ERR(rockchip->rst_gpio);
> >
> > - return 0;
> > + rockchip->rst = devm_reset_control_array_get_exclusive(&pdev->dev);
> > + if (IS_ERR(rockchip->rst))
> > + return dev_err_probe(&pdev->dev, PTR_ERR(rockchip->rst),
> > + "failed to get reset lines\n");
> > +
> > + return reset_control_assert(rockchip->rst);
>
> This makes "rockchip_pcie_resource_get" a bit of a misnomer, maybe move
> this out into rockchip_pcie_probe()?

Ah, yes that does make sense, thanks.

>
> > +
>
> Superfluous whitespace.
>
> regards
> Philipp
>