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author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-15 08:07:35 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-15 08:07:35 -0700 |
commit | 5f2434a66dfa4701b81b79a78eaf9c32da0f8839 (patch) | |
tree | 8c38f1fb0d0fbcd15e496df89be00ad8c4918a43 /Documentation/powerpc/dts-bindings/fsl/ssi.txt | |
parent | 278429cff8809958d25415ba0ed32b59866ab1a8 (diff) | |
parent | 6dc6472581f693b5fc95aebedf67b4960fb85cf0 (diff) |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (158 commits)
powerpc: Fix CHRP PCI config access for indirect_pci
powerpc/chrp: Fix detection of Python PCI host bridge on IBM CHRPs
powerpc: Fix 32-bit SMP boot on CHRP
powerpc: Fix link errors on 32-bit machines using legacy DMA
powerpc/pci: Improve detection of unassigned bridge resources
hvc_console: Fix free_irq in spinlocked section
powerpc: Get USE_STRICT_MM_TYPECHECKS working again
powerpc: Reflect the used arguments in machine_init() prototype
powerpc: Fix DMA offset for non-coherent DMA
powerpc: fix fsl_upm nand driver modular build
powerpc/83xx: add NAND support for the MPC8360E-RDK boards
powerpc: FPGA support for GE Fanuc SBC610
i2c: MPC8349E-mITX Power Management and GPIO expander driver
powerpc: reserve two DMA channels for audio in MPC8610 HPCD device tree
powerpc: document the "fsl,ssi-dma-channel" compatible property
powerpc: disable CHRP and PMAC support in various defconfigs
OF: add fsl,mcu-mpc8349emitx to the exception list
powerpc/83xx: add DS1374 RTC support for the MPC837xE-MDS boards
powerpc: remove support for bootmem-allocated memory for the DIU driver
powerpc: remove non-dependent load fsl_booke PTE_64BIT
...
Diffstat (limited to 'Documentation/powerpc/dts-bindings/fsl/ssi.txt')
-rw-r--r-- | Documentation/powerpc/dts-bindings/fsl/ssi.txt | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/Documentation/powerpc/dts-bindings/fsl/ssi.txt b/Documentation/powerpc/dts-bindings/fsl/ssi.txt index d100555d488..a2d963998a6 100644 --- a/Documentation/powerpc/dts-bindings/fsl/ssi.txt +++ b/Documentation/powerpc/dts-bindings/fsl/ssi.txt @@ -24,6 +24,12 @@ Required properties: "rj-master" - r.j., SSI is clock master "ac97-slave" - AC97 mode, SSI is clock slave "ac97-master" - AC97 mode, SSI is clock master +- fsl,playback-dma: phandle to a node for the DMA channel to use for + playback of audio. This is typically dictated by SOC + design. See the notes below. +- fsl,capture-dma: phandle to a node for the DMA channel to use for + capture (recording) of audio. This is typically dictated + by SOC design. See the notes below. Optional properties: - codec-handle : phandle to a 'codec' node that defines an audio @@ -36,3 +42,20 @@ Child 'codec' node required properties: Child 'codec' node optional properties: - clock-frequency : The frequency of the input clock, which typically comes from an on-board dedicated oscillator. + +Notes on fsl,playback-dma and fsl,capture-dma: + +On SOCs that have an SSI, specific DMA channels are hard-wired for playback +and capture. On the MPC8610, for example, SSI1 must use DMA channel 0 for +playback and DMA channel 1 for capture. SSI2 must use DMA channel 2 for +playback and DMA channel 3 for capture. The developer can choose which +DMA controller to use, but the channels themselves are hard-wired. The +purpose of these two properties is to represent this hardware design. + +The device tree nodes for the DMA channels that are referenced by +"fsl,playback-dma" and "fsl,capture-dma" must be marked as compatible with +"fsl,ssi-dma-channel". The SOC-specific compatible string (e.g. +"fsl,mpc8610-dma-channel") can remain. If these nodes are left as +"fsl,elo-dma-channel" or "fsl,eloplus-dma-channel", then the generic Elo DMA +drivers (fsldma) will attempt to use them, and it will conflict with the +sound drivers. |