[PATCH 0/9] PL08x further cleanups

[linux@arm.linux.org.uk (Russell King - ARM Linux)]

On Mon, Jul 25, 2011 at 07:08:31PM +0530, Vinod Koul wrote:
> Although gcc didnt like not handling other enums so warned:
> 
> drivers/dma/amba-pl08x.c: In function 'pl08x_width':
> drivers/dma/amba-pl08x.c:1119: warning: enumeration value
> 'DMA_SLAVE_BUSWIDTH_UNDEFINED' not handled in switch
> drivers/dma/amba-pl08x.c:1119: warning: enumeration value
> 'DMA_SLAVE_BUSWIDTH_8_BYTES' not handled in switch

Those must be new since I wrote the patch.

> which can be fixed as:
> 
> diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
> index 9aa2bd4..4925e0d 100644
> --- a/drivers/dma/amba-pl08x.c
> +++ b/drivers/dma/amba-pl08x.c
> @@ -1123,6 +1123,8 @@ static u32 pl08x_width(enum dma_slave_buswidth
> width)
>  		return PL080_WIDTH_16BIT;
>  	case DMA_SLAVE_BUSWIDTH_4_BYTES:
>  		return PL080_WIDTH_32BIT;
> +	default:
> +		return -EINVAL;
>  	}
>  	return ~0;
>  }
> 
> If you are okay, pls ack it

No.  This function is used as:

+       width = pl08x_width(addr_width);
+       if (width == ~0) {
                dev_err(&pl08x->adev->dev,
                        "bad runtime_config: alien address width\n");
                return -EINVAL;
        }

Notice that it returns a u32 so negative errnos don't make sense.  It
returns ~0 to indicate error.

The code is actually correct as it stands, it's just gcc deciding to
emit a warning for an unhandled enum value which isn't really unhandled.
Just move the 'return ~0;' at the end of the function inside the switch
as a default case to shut it up.