Re: [PATCH] MIPS: BCM63XX: Mark expected switch fall-through

From: Joe Perches
Date: Mon Aug 05 2019 - 15:15:09 EST


On Mon, 2019-08-05 at 13:55 -0500, Gustavo A. R. Silva wrote:
> Mark switch cases where we are expecting to fall through.
>
> This patch fixes the following warning (Building: bcm63xx_defconfig mips):
>
> arch/mips/pci/ops-bcm63xx.c: In function âbcm63xx_pcie_can_accessâ:
> arch/mips/pci/ops-bcm63xx.c:474:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
> if (PCI_SLOT(devfn) == 0)
> ^
> arch/mips/pci/ops-bcm63xx.c:477:2: note: here
> default:
> ^~~~~~~
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
> ---
> arch/mips/pci/ops-bcm63xx.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/mips/pci/ops-bcm63xx.c b/arch/mips/pci/ops-bcm63xx.c
> index d02eb9d16b55..925c72348fb6 100644
> --- a/arch/mips/pci/ops-bcm63xx.c
> +++ b/arch/mips/pci/ops-bcm63xx.c
> @@ -474,6 +474,7 @@ static int bcm63xx_pcie_can_access(struct pci_bus *bus, int devfn)
> if (PCI_SLOT(devfn) == 0)
> return bcm_pcie_readl(PCIE_DLSTATUS_REG)
> & DLSTATUS_PHYLINKUP;
> + /* else, fall through */
> default:
> return false;
> }

Perhaps clearer as:
---
arch/mips/pci/ops-bcm63xx.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/mips/pci/ops-bcm63xx.c b/arch/mips/pci/ops-bcm63xx.c
index d02eb9d16b55..a5e4b1905958 100644
--- a/arch/mips/pci/ops-bcm63xx.c
+++ b/arch/mips/pci/ops-bcm63xx.c
@@ -471,12 +471,11 @@ static int bcm63xx_pcie_can_access(struct pci_bus *bus, int devfn)
case PCIE_BUS_BRIDGE:
return PCI_SLOT(devfn) == 0;
case PCIE_BUS_DEVICE:
- if (PCI_SLOT(devfn) == 0)
- return bcm_pcie_readl(PCIE_DLSTATUS_REG)
- & DLSTATUS_PHYLINKUP;
- default:
- return false;
+ return PCI_SLOT(devfn) == 0 &&
+ bcm_pcie_readl(PCIE_DLSTATUS_REG) & DLSTATUS_PHYLINKUP;
}
+
+ return false;
}

static int bcm63xx_pcie_read(struct pci_bus *bus, unsigned int devfn,