dma: imx-sdma: move to generic device tree bindings

Update imx-sdma driver to adopt generic DMA device tree bindings.  It
calls of_dma_controller_register() with imx-sdma specific of_dma_xlate
to get the generic DMA device tree helper support.  The #dma-cells for
imx-sdma must be 3, which includes request ID, peripheral type and
priority.

The existing way of requesting channel, clients directly call
dma_request_channel(), still work there, and will be removed after
all imx-sdma clients get converted to generic DMA device tree helper.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 56 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt
index d1e3f44..68cee4f5 100644
--- a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt
+++ b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt
@@ -4,14 +4,70 @@ Required properties:
 - compatible : Should be "fsl,<chip>-sdma"
 - reg : Should contain SDMA registers location and length
 - interrupts : Should contain SDMA interrupt
+- #dma-cells : Must be <3>.
+  The first cell specifies the DMA request/event ID.  See details below
+  about the second and third cell.
 - fsl,sdma-ram-script-name : Should contain the full path of SDMA RAM
   scripts firmware
 
+The second cell of dma phandle specifies the peripheral type of DMA transfer.
+The full ID of peripheral types can be found below.
+
+	ID	transfer type
+	---------------------
+	0	MCU domain SSI
+	1	Shared SSI
+	2	MMC
+	3	SDHC
+	4	MCU domain UART
+	5	Shared UART
+	6	FIRI
+	7	MCU domain CSPI
+	8	Shared CSPI
+	9	SIM
+	10	ATA
+	11	CCM
+	12	External peripheral
+	13	Memory Stick Host Controller
+	14	Shared Memory Stick Host Controller
+	15	DSP
+	16	Memory
+	17	FIFO type Memory
+	18	SPDIF
+	19	IPU Memory
+	20	ASRC
+	21	ESAI
+
+The third cell specifies the transfer priority as below.
+
+	ID	transfer priority
+	-------------------------
+	0	High
+	1	Medium
+	2	Low
+
 Examples:
 
 sdma@83fb0000 {
 	compatible = "fsl,imx51-sdma", "fsl,imx35-sdma";
 	reg = <0x83fb0000 0x4000>;
 	interrupts = <6>;
+	#dma-cells = <3>;
 	fsl,sdma-ram-script-name = "sdma-imx51.bin";
 };
+
+DMA clients connected to the i.MX SDMA controller must use the format
+described in the dma.txt file.
+
+Examples:
+
+ssi2: ssi@70014000 {
+	compatible = "fsl,imx51-ssi", "fsl,imx21-ssi";
+	reg = <0x70014000 0x4000>;
+	interrupts = <30>;
+	clocks = <&clks 49>;
+	dmas = <&sdma 24 1 0>,
+	       <&sdma 25 1 0>;
+	dma-names = "rx", "tx";
+	fsl,fifo-depth = <15>;
+};