If device has no max_seg_size set, we assume that there is no limit and force it to DMA_BIT_MASK(32) to always use contiguous mappings in DMA address space.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- arch/arm/mm/dma-mapping.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 7a996aa..8161102 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -2051,6 +2051,22 @@ int arm_iommu_attach_device(struct device *dev, { int err;
+ /* + * if device has no max_seg_size set, we assume that there is no limit + * and force it to DMA_BIT_MASK(32) to always use contiguous mappings + * in DMA address space + */ + if (!dev->dma_parms) { + dev->dma_parms = kzalloc(sizeof(*dev->dma_parms), GFP_KERNEL); + if (!dev->dma_parms) + return -ENOMEM; + } + if (!dev->dma_parms->max_segment_size) { + err = dma_set_max_seg_size(dev, DMA_BIT_MASK(32)); + if (err) + return err; + } + err = iommu_attach_device(mapping->domain, dev); if (err) return err;