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

From: Philipp Zabel
Date: Mon Apr 25 2022 - 05:21:23 EST


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()?

> +

Superfluous whitespace.

regards
Philipp