----- Original Message ----
> From: Kumar Gala <ga...@kernel.crashing.org>
> To: linuxppc-...@ozlabs.org
> Sent: Mon, August 2, 2010 12:21:22 PM
> Subject: [PATCH] powerpc: Dont require a dma_ops struct to set dma mask
>
> The only reason to require a dma_ops struct is to see if it has
> implemented set_dma_mask. If not we can fall back to setting the mask
> directly.
>
> This resolves an issue with how to sequence the setting of a DMA mask
> for platform devices. Before we had an issue in that we have no way of
> setting the DMA mask before the various low level bus notifiers get
> called that might check it (swiotlb).
>
> So now we can do:
>
> pdev = platform_device_alloc("foobar", 0);
> dma_set_mask(&pdev->dev, DMA_BIT_MASK(37));
> platform_device_register(pdev);
>
> And expect the right thing to happen with the bus notifiers get called
> via platform_device_register.
>
> Signed-off-by: Kumar Gala <ga...@kernel.crashing.org>
> ---
> arch/powerpc/include/asm/dma-mapping.h | 4 +---
> 1 files changed, 1 insertions(+), 3 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/dma-mapping.h
>b/arch/powerpc/include/asm/dma-mapping.h
> index c85ef23..17d5c17 100644
> --- a/arch/powerpc/include/asm/dma-mapping.h
> +++ b/arch/powerpc/include/asm/dma-mapping.h
> @@ -131,9 +131,7 @@ static inline int dma_set_mask(struct device *dev, u64
>dma_mask)
> {
> struct dma_map_ops *dma_ops = get_dma_ops(dev);
>
> - if (unlikely(dma_ops == NULL))
> - return -EIO;
> - if (dma_ops->set_dma_mask != NULL)
> + if (unlikely(dma_ops == NULL) && (dma_ops->set_dma_mask != NULL))
> return dma_ops->set_dma_mask(dev, dma_mask);
> if (!dev->dma_mask || !dma_supported(dev, dma_mask))
> return -EIO;
> --
> 1.6.0.6
>
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev
>
Isn't that test wrong? Perhaps you meant to test for dma_ops non-null before
dereferencing it?
-roger
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
