[PATCH 27/51] DMA-API: provide a helper to setup DMA masks
From: Russell King <hidden>
Date: 2013-09-19 21:52:02
Also in:
alsa-devel, dri-devel, linux-arm-kernel, linux-crypto, linux-devicetree, linux-ide, linux-mmc, linux-nvme, linux-omap, linux-samsung-soc, linux-scsi, linux-tegra, linux-wireless, linuxppc-dev, netdev
Subsystem:
dma mapping helpers, the rest · Maintainers:
Marek Szyprowski, Linus Torvalds
Many drivers contain code such as: dev->dma_mask = &dev->coherent_dma_mask; dev->coherent_dma_mask = MASK; Let's move this pattern out of drivers and have the DMA API provide a helper for it. This helper uses dma_set_mask_and_coherent() to allow platform issues to be properly dealt with via dma_set_mask()/ dma_is_supported(). Signed-off-by: Russell King <redacted> --- include/linux/dma-mapping.h | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index ec951f9..27d1421 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h@@ -111,6 +111,16 @@ static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask) return rc; } +/* + * Similar to the above, except it deals with the case where the device + * does not have dev->dma_mask appropriately setup. + */ +static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask) +{ + dev->dma_mask = &dev->coherent_dma_mask; + return dma_set_mask_and_coherent(dev, mask); +} + extern u64 dma_get_required_mask(struct device *dev); static inline unsigned int dma_get_max_seg_size(struct device *dev)
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1.7.4.4