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author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-26 09:24:48 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-26 09:24:48 -0800 |
commit | 5115f3c19d17851aaff5a857f55b4a019c908775 (patch) | |
tree | 0d02cf01e12e86365f4f5e3b234f986daef181a7 /Documentation/devicetree/bindings/dma/dma.txt | |
parent | c41b3810c09e60664433548c5218cc6ece6a8903 (diff) | |
parent | 17166a3b6e88b93189e6be5f7e1335a3cc4fa965 (diff) | |
download | op-kernel-dev-5115f3c19d17851aaff5a857f55b4a019c908775.zip op-kernel-dev-5115f3c19d17851aaff5a857f55b4a019c908775.tar.gz |
Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
Pull slave-dmaengine updates from Vinod Koul:
"This is fairly big pull by my standards as I had missed last merge
window. So we have the support for device tree for slave-dmaengine,
large updates to dw_dmac driver from Andy for reusing on different
architectures. Along with this we have fixes on bunch of the drivers"
Fix up trivial conflicts, usually due to #include line movement next to
each other.
* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (111 commits)
Revert "ARM: SPEAr13xx: Pass DW DMAC platform data from DT"
ARM: dts: pl330: Add #dma-cells for generic dma binding support
DMA: PL330: Register the DMA controller with the generic DMA helpers
DMA: PL330: Add xlate function
DMA: PL330: Add new pl330 filter for DT case.
dma: tegra20-apb-dma: remove unnecessary assignment
edma: do not waste memory for dma_mask
dma: coh901318: set residue only if dma is in progress
dma: coh901318: avoid unbalanced locking
dmaengine.h: remove redundant else keyword
dma: of-dma: protect list write operation by spin_lock
dmaengine: ste_dma40: do not remove descriptors for cyclic transfers
dma: of-dma.c: fix memory leakage
dw_dmac: apply default dma_mask if needed
dmaengine: ioat - fix spare sparse complain
dmaengine: move drivers/of/dma.c -> drivers/dma/of-dma.c
ioatdma: fix race between updating ioat->head and IOAT_COMPLETION_PENDING
dw_dmac: add support for Lynxpoint DMA controllers
dw_dmac: return proper residue value
dw_dmac: fill individual length of descriptor
...
Diffstat (limited to 'Documentation/devicetree/bindings/dma/dma.txt')
-rw-r--r-- | Documentation/devicetree/bindings/dma/dma.txt | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/dma.txt b/Documentation/devicetree/bindings/dma/dma.txt new file mode 100644 index 0000000..8f504e6 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/dma.txt @@ -0,0 +1,81 @@ +* Generic DMA Controller and DMA request bindings + +Generic binding to provide a way for a driver using DMA Engine to retrieve the +DMA request or channel information that goes from a hardware device to a DMA +controller. + + +* DMA controller + +Required property: +- #dma-cells: Must be at least 1. Used to provide DMA controller + specific information. See DMA client binding below for + more details. + +Optional properties: +- dma-channels: Number of DMA channels supported by the controller. +- dma-requests: Number of DMA requests signals supported by the + controller. + +Example: + + dma: dma@48000000 { + compatible = "ti,omap-sdma"; + reg = <0x48000000 0x1000>; + interrupts = <0 12 0x4 + 0 13 0x4 + 0 14 0x4 + 0 15 0x4>; + #dma-cells = <1>; + dma-channels = <32>; + dma-requests = <127>; + }; + + +* DMA client + +Client drivers should specify the DMA property using a phandle to the controller +followed by DMA controller specific data. + +Required property: +- dmas: List of one or more DMA specifiers, each consisting of + - A phandle pointing to DMA controller node + - A number of integer cells, as determined by the + #dma-cells property in the node referenced by phandle + containing DMA controller specific information. This + typically contains a DMA request line number or a + channel number, but can contain any data that is used + required for configuring a channel. +- dma-names: Contains one identifier string for each DMA specifier in + the dmas property. The specific strings that can be used + are defined in the binding of the DMA client device. + Multiple DMA specifiers can be used to represent + alternatives and in this case the dma-names for those + DMA specifiers must be identical (see examples). + +Examples: + +1. A device with one DMA read channel, one DMA write channel: + + i2c1: i2c@1 { + ... + dmas = <&dma 2 /* read channel */ + &dma 3>; /* write channel */ + dma-names = "rx", "tx"; + ... + }; + +2. A single read-write channel with three alternative DMA controllers: + + dmas = <&dma1 5 + &dma2 7 + &dma3 2>; + dma-names = "rx-tx", "rx-tx", "rx-tx"; + +3. A device with three channels, one of which has two alternatives: + + dmas = <&dma1 2 /* read channel */ + &dma1 3 /* write channel */ + &dma2 0 /* error read */ + &dma3 0>; /* alternative error read */ + dma-names = "rx", "tx", "error", "error"; |