Re: [PATCH 1/3] PCI: dwc: Standardize link status check to return bool

[Niklas Cassel <cassel@kernel.org>]

Hello Hans,

On Tue, Apr 29, 2025 at 01:10:25AM +0800, Hans Zhang wrote:
> Modify link_up functions across multiple DWC PCIe controllers to return
> bool instead of int. Simplify conditional checks by directly returning
> logical evaluations. This improves code clarity and aligns with PCIe
> status semantics.
> 
> Signed-off-by: Hans Zhang <18255117159@163.com>
> ---
>  drivers/pci/controller/dwc/pci-dra7xx.c       | 2 +-
>  drivers/pci/controller/dwc/pci-exynos.c       | 4 ++--
>  drivers/pci/controller/dwc/pci-keystone.c     | 5 ++---
>  drivers/pci/controller/dwc/pci-meson.c        | 6 +++---
>  drivers/pci/controller/dwc/pcie-armada8k.c    | 6 +++---
>  drivers/pci/controller/dwc/pcie-designware.c  | 2 +-
>  drivers/pci/controller/dwc/pcie-designware.h  | 4 ++--
>  drivers/pci/controller/dwc/pcie-dw-rockchip.c | 2 +-
>  drivers/pci/controller/dwc/pcie-histb.c       | 9 +++------
>  drivers/pci/controller/dwc/pcie-keembay.c     | 2 +-
>  drivers/pci/controller/dwc/pcie-kirin.c       | 7 ++-----
>  drivers/pci/controller/dwc/pcie-qcom-ep.c     | 4 ++--
>  drivers/pci/controller/dwc/pcie-qcom.c        | 2 +-
>  drivers/pci/controller/dwc/pcie-rcar-gen4.c   | 2 +-
>  drivers/pci/controller/dwc/pcie-spear13xx.c   | 7 ++-----
>  drivers/pci/controller/dwc/pcie-tegra194.c    | 2 +-
>  drivers/pci/controller/dwc/pcie-uniphier.c    | 2 +-
>  drivers/pci/controller/dwc/pcie-visconti.c    | 2 +-
>  18 files changed, 30 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
> index 33d6bf460ffe..4ef25d14312b 100644
> --- a/drivers/pci/controller/dwc/pci-dra7xx.c
> +++ b/drivers/pci/controller/dwc/pci-dra7xx.c
> @@ -118,7 +118,7 @@ static u64 dra7xx_pcie_cpu_addr_fixup(struct dw_pcie *pci, u64 cpu_addr)
>  	return cpu_addr & DRA7XX_CPU_TO_BUS_ADDR;
>  }
>  
> -static int dra7xx_pcie_link_up(struct dw_pcie *pci)
> +static bool dra7xx_pcie_link_up(struct dw_pcie *pci)
>  {
>  	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pci);
>  	u32 reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);
> diff --git a/drivers/pci/controller/dwc/pci-exynos.c b/drivers/pci/controller/dwc/pci-exynos.c
> index ace736b025b1..d4a25d376b11 100644
> --- a/drivers/pci/controller/dwc/pci-exynos.c
> +++ b/drivers/pci/controller/dwc/pci-exynos.c
> @@ -209,12 +209,12 @@ static struct pci_ops exynos_pci_ops = {
>  	.write = exynos_pcie_wr_own_conf,
>  };
>  
> -static int exynos_pcie_link_up(struct dw_pcie *pci)
> +static bool exynos_pcie_link_up(struct dw_pcie *pci)
>  {
>  	struct exynos_pcie *ep = to_exynos_pcie(pci);
>  	u32 val = exynos_pcie_readl(ep->elbi_base, PCIE_ELBI_RDLH_LINKUP);
>  
> -	return (val & PCIE_ELBI_XMLH_LINKUP);
> +	return !!(val & PCIE_ELBI_XMLH_LINKUP);

!! is not needed here, or in other places.

When assigning to the bool any non-zero value becomes 1.

!! is usually only needed when needing to store an explicit 1 or 0 in an int.


Kind regards,
Niklas