Re: [patch v3] doc: DMA-mapping.txt has undeclared variables [Bug 10397]

[Matthew Wilcox <matthew@wil.cx>]

On Mon, Apr 28, 2008 at 05:58:49AM -0700, Matti Linnanvuori wrote:
> From: Matti Linnanvuori <mattilinnanvuori@yahoo.com>
> 
> Consistently use pdev as the variable of type struct pci_dev *.
> Update DMA mapping documentation to use 'pdev' rather than 'dev' in 
> example code that calls routines expecting 'struct pci_device *', since 'dev' 
> might make readers think they're passing 'struct device *' parameters.
> Bug 10397.
> 
> Signed-off-by: Matti Linnanvuori <mattilinnanvuori@yahoo.com>

Acked-by: Matthew Wilcox <willy@linux.intel.com>

> -    cpu_addr = pci_alloc_consistent(dev, size, &dma_handle);
> +    cpu_addr = pci_alloc_consistent(pdev, size, &dma_handle);
>  
> -where dev is a struct pci_dev *. You should pass NULL for PCI like buses
> +where pdev is a struct pci_dev *. You should pass NULL for PCI like buses
>  where devices don't have struct pci_dev (like ISA, EISA).  This may be
>  called in interrupt context. 

The second sentence is misleading (but it's unrelated to this patch).
If you don't have a pdev, you should be using dma_alloc_coherent()
instead (see DMA-API.txt).  Want to make another patch?  ;-)

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