pcie-mediatek.c coverity issue #1437218

pcie-mediatek.c coverity issue #1437218

[Bjorn Helgaas]

Hi Ryder,

Please take a look at this issue reported by Coverity:

 760 static int mtk_pcie_startup_port(struct mtk_pcie_port *port)
 761 {
 762        struct mtk_pcie *pcie = port->pcie;

CID 1437218 (#1 of 1): Wrong operator used
(CONSTANT_EXPRESSION_RESULT) operator_confusion: (port->slot << 3) & 7
is always 0 regardless of the values of its operands. This occurs as
an initializer.

    	Did you intend to use right-shift (>>) in port->slot << 3?

 763        u32 func = PCI_FUNC(port->slot << 3);
 764        u32 slot = PCI_SLOT(port->slot << 3);

Re: pcie-mediatek.c coverity issue #1437218

[Matthias Brugger]

Hi Ryder,

On 27/10/2020 17:19, Bjorn Helgaas wrote:
> Hi Ryder,
> 
> Please take a look at this issue reported by Coverity:
> 
>   760 static int mtk_pcie_startup_port(struct mtk_pcie_port *port)
>   761 {
>   762        struct mtk_pcie *pcie = port->pcie;
> 
> CID 1437218 (#1 of 1): Wrong operator used
> (CONSTANT_EXPRESSION_RESULT) operator_confusion: (port->slot << 3) & 7
> is always 0 regardless of the values of its operands. This occurs as
> an initializer.
> 
>      	Did you intend to use right-shift (>>) in port->slot << 3?
> 
>   763        u32 func = PCI_FUNC(port->slot << 3);
>   764        u32 slot = PCI_SLOT(port->slot << 3);
> 

AFAIK pcie is working. Could you have a look on this code snippet? It seems as 
if there is something fishy.

Thanks,
Matthias