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

[Philipp Zabel <p.zabel@pengutronix.de>]

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@mediatek.com>
> Acked-by: Ryder Lee <ryder.lee@mediatek.com>
> ---
>  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