On Tue, Oct 27, 2020 at 02:00:11PM +0800, Wan Ahmad Zainie wrote: > +static int keembay_pcie_link_up(struct dw_pcie *pci) > +{ > + struct keembay_pcie *pcie = dev_get_drvdata(pci->dev); > + u32 val, mask; > + > + val = keembay_pcie_readl(pcie, PCIE_REGS_PCIE_SII_PM_STATE); > + mask = SMLH_LINK_UP | RDLH_LINK_UP; > + > + return !!((val & mask) == mask); I think the "!!" is redundant since you're applying it to a value that's a boolean already. So you should be able to do: return (val & mask) == mask; But it seems like "mask" just obfuscates a little bit, too. Personally I think it'd be easier to add something like: #define PCIE_REGS_PCIE_SII_LINK_UP (SMLH_LINK_UP | RDLH_LINK_UP) and then: if ((val & PCIE_REGS_PCIE_SII_LINK_UP) == PCIE_REGS_PCIE_SII_LINK_UP) return 1; return 0; or even: return (val & PCIE_REGS_PCIE_SII_LINK_UP) == PCIE_REGS_PCIE_SII_LINK_UP; > +static int keembay_pcie_establish_link(struct dw_pcie *pci) > +{ > + return 0; > +} Are you sure you need this? I see other cases where the .start_link pointer is left NULL, e.g., pci-exynos.c, pci-imx6.c, dw_ls1021_pcie_ops, etc. > +static int keembay_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no, > + enum pci_epc_irq_type type, > + u16 interrupt_num) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_ep(ep); > + > + switch (type) { > + case PCI_EPC_IRQ_LEGACY: > + /* Legacy interrupts are not supported in Keem Bay */ > + dev_err(pci->dev, "Unsupported IRQ type\n"); Might be nice to mention "legacy" here. > + return -EINVAL; > + case PCI_EPC_IRQ_MSI: > + return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num); > + case PCI_EPC_IRQ_MSIX: > + return dw_pcie_ep_raise_msix_irq(ep, func_no, interrupt_num); > + default: > + dev_err(pci->dev, "Unknown IRQ type\n"); And maybe include the %d of "type"?