[PATCH 4/8] of: dma: Split of_configure_dma() into mask and ops configuration

Tomasz Figa tfiga at chromium.org
Fri Aug 12 00:31:47 PDT 2016


Hi,

On Tue, Aug 9, 2016 at 7:49 AM, Sricharan R <sricharan at codeaurora.org> wrote:
> From: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
>
> The of_configure_dma() function configures both the DMA masks and ops.
> Moving DMA ops configuration to probe time would thus also delay
> configuration of the DMA masks, which might not be safe. To avoid issues

Do we know any example cases when it might be unsafe? I think we kind
of rely on the fact that DMA mapping (and so DMA masks as well) is not
used before probing the device anyway, because we let the IOMMU
attachment happen at probe time, which essentially makes any earlier
attempts to use DMA mapping on such device incorrect.

Best regards,
Tomasz



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