diff options
author | Barry Song <Baohua.Song@csr.com> | 2014-03-27 11:49:31 +0400 |
---|---|---|
committer | Vinod Koul <vinod.koul@intel.com> | 2014-03-29 17:50:13 +0400 |
commit | 2e041c94628c2f0b8b704dc092802ddeaa70c6e9 (patch) | |
tree | 5dce0f4735a928382b5e47be8d84c6ffe80b03f8 | |
parent | 80b0e0abfbcf9897ee263a79bc4cbdcfeca72431 (diff) | |
download | linux-2e041c94628c2f0b8b704dc092802ddeaa70c6e9.tar.xz |
dmaengine: sirf: enable generic dt binding for dma channels
move to support of_dma_request_slave_channel() and dma_request_slave_channel.
we add a xlate() to let dma clients be able to find right dma_chan by generic
"dmas" properties in dts.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
-rw-r--r-- | Documentation/devicetree/bindings/dma/sirfsoc-dma.txt | 43 | ||||
-rw-r--r-- | arch/arm/boot/dts/atlas6.dtsi | 2 | ||||
-rw-r--r-- | arch/arm/boot/dts/prima2.dtsi | 2 | ||||
-rw-r--r-- | drivers/dma/sirf-dma.c | 23 |
4 files changed, 70 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/sirfsoc-dma.txt b/Documentation/devicetree/bindings/dma/sirfsoc-dma.txt new file mode 100644 index 000000000000..ecbc96ad36f8 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/sirfsoc-dma.txt @@ -0,0 +1,43 @@ +* CSR SiRFSoC DMA controller + +See dma.txt first + +Required properties: +- compatible: Should be "sirf,prima2-dmac" or "sirf,marco-dmac" +- reg: Should contain DMA registers location and length. +- interrupts: Should contain one interrupt shared by all channel +- #dma-cells: must be <1>. used to represent the number of integer + cells in the dmas property of client device. +- clocks: clock required + +Example: + +Controller: +dmac0: dma-controller@b00b0000 { + compatible = "sirf,prima2-dmac"; + reg = <0xb00b0000 0x10000>; + interrupts = <12>; + clocks = <&clks 24>; + #dma-cells = <1>; +}; + + +Client: +Fill the specific dma request line in dmas. In the below example, spi0 read +channel request line is 9 of the 2nd dma controller, while write channel uses +4 of the 2nd dma controller; spi1 read channel request line is 12 of the 1st +dma controller, while write channel uses 13 of the 1st dma controller: + +spi0: spi@b00d0000 { + compatible = "sirf,prima2-spi"; + dmas = <&dmac1 9>, + <&dmac1 4>; + dma-names = "rx", "tx"; +}; + +spi1: spi@b0170000 { + compatible = "sirf,prima2-spi"; + dmas = <&dmac0 12>, + <&dmac0 13>; + dma-names = "rx", "tx"; +}; diff --git a/arch/arm/boot/dts/atlas6.dtsi b/arch/arm/boot/dts/atlas6.dtsi index f8674bcc4489..ec23b5c86fb7 100644 --- a/arch/arm/boot/dts/atlas6.dtsi +++ b/arch/arm/boot/dts/atlas6.dtsi @@ -269,6 +269,7 @@ reg = <0xb00b0000 0x10000>; interrupts = <12>; clocks = <&clks 24>; + #dma-cells = <1>; }; dmac1: dma-controller@b0160000 { @@ -277,6 +278,7 @@ reg = <0xb0160000 0x10000>; interrupts = <13>; clocks = <&clks 25>; + #dma-cells = <1>; }; vip@b00C0000 { diff --git a/arch/arm/boot/dts/prima2.dtsi b/arch/arm/boot/dts/prima2.dtsi index 0e219932d7cc..3a15dee2e8ab 100644 --- a/arch/arm/boot/dts/prima2.dtsi +++ b/arch/arm/boot/dts/prima2.dtsi @@ -286,6 +286,7 @@ reg = <0xb00b0000 0x10000>; interrupts = <12>; clocks = <&clks 24>; + #dma-cells = <1>; }; dmac1: dma-controller@b0160000 { @@ -294,6 +295,7 @@ reg = <0xb0160000 0x10000>; interrupts = <13>; clocks = <&clks 25>; + #dma-cells = <1>; }; vip@b00C0000 { diff --git a/drivers/dma/sirf-dma.c b/drivers/dma/sirf-dma.c index d4d3a3109b16..a1bd8298d55f 100644 --- a/drivers/dma/sirf-dma.c +++ b/drivers/dma/sirf-dma.c @@ -18,6 +18,7 @@ #include <linux/of_device.h> #include <linux/of_platform.h> #include <linux/clk.h> +#include <linux/of_dma.h> #include <linux/sirfsoc_dma.h> #include "dmaengine.h" @@ -659,6 +660,18 @@ static int sirfsoc_dma_device_slave_caps(struct dma_chan *dchan, return 0; } +static struct dma_chan *of_dma_sirfsoc_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct sirfsoc_dma *sdma = ofdma->of_dma_data; + unsigned int request = dma_spec->args[0]; + + if (request > SIRFSOC_DMA_CHANNELS) + return NULL; + + return dma_get_slave_channel(&sdma->channels[request].chan); +} + static int sirfsoc_dma_probe(struct platform_device *op) { struct device_node *dn = op->dev.of_node; @@ -764,11 +777,20 @@ static int sirfsoc_dma_probe(struct platform_device *op) if (ret) goto free_irq; + /* Device-tree DMA controller registration */ + ret = of_dma_controller_register(dn, of_dma_sirfsoc_xlate, sdma); + if (ret) { + dev_err(dev, "failed to register DMA controller\n"); + goto unreg_dma_dev; + } + pm_runtime_enable(&op->dev); dev_info(dev, "initialized SIRFSOC DMAC driver\n"); return 0; +unreg_dma_dev: + dma_async_device_unregister(dma); free_irq: free_irq(sdma->irq, sdma); irq_dispose: @@ -781,6 +803,7 @@ static int sirfsoc_dma_remove(struct platform_device *op) struct device *dev = &op->dev; struct sirfsoc_dma *sdma = dev_get_drvdata(dev); + of_dma_controller_free(op->dev.of_node); dma_async_device_unregister(&sdma->dma); free_irq(sdma->irq, sdma); irq_dispose_mapping(sdma->irq); |