Re: [v2,2/3] PCI: mediatek: Add new generation controller support

From: Philipp Zabel
Date: Fri Sep 11 2020 - 12:37:45 EST


Hi Jianjun,

On Thu, 2020-09-10 at 11:45 +0800, Jianjun Wang wrote:
> MediaTek's PCIe host controller has three generation HWs, the new
> generation HW is an individual bridge, it supoorts Gen3 speed and
> up to 256 MSI interrupt numbers for multi-function devices.
>
> Add support for new Gen3 controller which can be found on MT8192.
>
> Signed-off-by: Jianjun Wang <jianjun.wang@xxxxxxxxxxxx>
> Acked-by: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
> ---
> drivers/pci/controller/Kconfig | 14 +
> drivers/pci/controller/Makefile | 1 +
> drivers/pci/controller/pcie-mediatek-gen3.c | 1076 +++++++++++++++++++
> 3 files changed, 1091 insertions(+)
> create mode 100644 drivers/pci/controller/pcie-mediatek-gen3.c
>
[...]
> diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
> new file mode 100644
> index 000000000000..f8c8bdf88d33
> --- /dev/null
> +++ b/drivers/pci/controller/pcie-mediatek-gen3.c
[...]
> +static int mtk_pcie_power_up(struct mtk_pcie_port *port)
> +{
> + struct device *dev = port->dev;
> + int err;
> +
> + port->phy_reset = devm_reset_control_get_optional(dev, "phy-rst");

Please use devm_reset_control_get_optional_exclusive() instead.

> + if (PTR_ERR(port->phy_reset) == -EPROBE_DEFER)
> + return PTR_ERR(port->phy_reset);

This should be

if (IS_ERR(port->phy_reset))
return PTR_ERR(port->phy_reset);

there is no reason to continue if this throws -ENOMEM, for example.

regards
Philipp