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authorMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-04-21 12:33:03 +0300
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-04-21 15:44:55 +0300
commit64131a87f2aae2ed9e05d8227c5b009ca6c50d98 (patch)
treefdea23fd59216120bf54a48c60ca24489a733f14 /Documentation/devicetree/bindings/dma/brcm,bcm2835-dma.txt
parent676ee36be04985062522804c2de04f0764212be6 (diff)
parent2c33ce009ca2389dbf0535d0672214d09738e35e (diff)
downloadlinux-64131a87f2aae2ed9e05d8227c5b009ca6c50d98.tar.xz
Merge branch 'drm-next-merged' of git://people.freedesktop.org/~airlied/linux into v4l_for_linus
* 'drm-next-merged' of git://people.freedesktop.org/~airlied/linux: (9717 commits) media-bus: Fixup RGB444_1X12, RGB565_1X16, and YUV8_1X24 media bus format hexdump: avoid warning in test function fs: take i_mutex during prepare_binprm for set[ug]id executables smp: Fix error case handling in smp_call_function_*() iommu-common: Fix PARISC compile-time warnings sparc: Make LDC use common iommu poll management functions sparc: Make sparc64 use scalable lib/iommu-common.c functions Break up monolithic iommu table/lock into finer graularity pools and lock sparc: Revert generic IOMMU allocator. tools/power turbostat: correct dumped pkg-cstate-limit value tools/power turbostat: calculate TSC frequency from CPUID(0x15) on SKL tools/power turbostat: correct DRAM RAPL units on recent Xeon processors tools/power turbostat: Initial Skylake support tools/power turbostat: Use $(CURDIR) instead of $(PWD) and add support for O= option in Makefile tools/power turbostat: modprobe msr, if needed tools/power turbostat: dump MSR_TURBO_RATIO_LIMIT2 tools/power turbostat: use new MSR_TURBO_RATIO_LIMIT names Bluetooth: hidp: Fix regression with older userspace and flags validation config: Enable NEED_DMA_MAP_STATE by default when SWIOTLB is selected perf/x86/intel/pt: Fix and clean up error handling in pt_event_add() ... That solves several merge conflicts: Documentation/DocBook/media/v4l/subdev-formats.xml Documentation/devicetree/bindings/vendor-prefixes.txt drivers/staging/media/mn88473/mn88473.c include/linux/kconfig.h include/uapi/linux/media-bus-format.h The ones at subdev-formats.xml and media-bus-format.h are not trivial. That's why we opted to merge from DRM.
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+* BCM2835 DMA controller
+
+The BCM2835 DMA controller has 16 channels in total.
+Only the lower 13 channels have an associated IRQ.
+Some arbitrary channels are used by the firmware
+(1,3,6,7 in the current firmware version).
+The channels 0,2 and 3 have special functionality
+and should not be used by the driver.
+
+Required properties:
+- compatible: Should be "brcm,bcm2835-dma".
+- reg: Should contain DMA registers location and length.
+- interrupts: Should contain the DMA interrupts associated
+ to the DMA channels in ascending order.
+- #dma-cells: Must be <1>, the cell in the dmas property of the
+ client device represents the DREQ number.
+- brcm,dma-channel-mask: Bit mask representing the channels
+ not used by the firmware in ascending order,
+ i.e. first channel corresponds to LSB.
+
+Example:
+
+dma: dma@7e007000 {
+ compatible = "brcm,bcm2835-dma";
+ reg = <0x7e007000 0xf00>;
+ interrupts = <1 16>,
+ <1 17>,
+ <1 18>,
+ <1 19>,
+ <1 20>,
+ <1 21>,
+ <1 22>,
+ <1 23>,
+ <1 24>,
+ <1 25>,
+ <1 26>,
+ <1 27>,
+ <1 28>;
+
+ #dma-cells = <1>;
+ brcm,dma-channel-mask = <0x7f35>;
+};
+
+DMA clients connected to the BCM2835 DMA controller must use the format
+described in the dma.txt file, using a two-cell specifier for each channel.
+
+Example:
+
+bcm2835_i2s: i2s@7e203000 {
+ compatible = "brcm,bcm2835-i2s";
+ reg = < 0x7e203000 0x20>,
+ < 0x7e101098 0x02>;
+
+ dmas = <&dma 2>,
+ <&dma 3>;
+ dma-names = "tx", "rx";
+};