[PATCH v5 1/4] dt-bindings: mailbox: Document Hi6220 mailbox driver

[Leo Yan <leo.yan@linaro.org>]

Document DT binding for Hisilicon Hi6220 mailbox driver.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
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 .../bindings/mailbox/hisilicon,hi6220-mailbox.txt  | 90 ++++++++++++++++++++++
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 create mode 100644 Documentation/devicetree/bindings/mailbox/hisilicon,hi6220-mailbox.txt

diff --git a/Documentation/devicetree/bindings/mailbox/hisilicon,hi6220-mailbox.txt b/Documentation/devicetree/bindings/mailbox/hisilicon,hi6220-mailbox.txt
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+Hisilicon Hi6220 Mailbox Driver
+===============================
+
+Hisilicon Hi6220 mailbox supports up to 32 channels. Each channel
+is unidirectional with a maximum message size of 8 words. I/O is
+performed using register access (there is no DMA) and the cell
+raises an interrupt when messages are received.
+
+Mailbox Device Node:
+====================
+
+Required properties:
+--------------------
+- compatible:		Shall be "hisilicon,hi6220-mbox"
+- reg:			Contains the mailbox register address range (base
+			address and length); the first item is for IPC
+			registers, the second item is shared buffer for
+			slots.
+- #mbox-cells		Common mailbox binding property to identify the number
+			of cells required for the mailbox specifier. Should be 1.
+- interrupts:		Contains the interrupt information for the mailbox
+			device. The format is dependent on which interrupt
+			controller the SoCs use.
+
+Optional Properties:
+--------------------
+- hi6220,mbox-tx-noirq: Flag to allow the client user of this mailbox driver
+			to send messages without triggering a TX completion
+			interrupt.
+
+Child Nodes:
+============
+A child node is used for representing the actual sub-mailbox device that is
+used for the communication between the host processor and a remote processor.
+Each child node should have a unique node name across all the different
+mailbox device nodes.
+
+Required properties:
+--------------------
+- hi6220,mbox-tx:	sub-mailbox descriptor property defining Tx channel
+- hi6220,mbox-rx:	sub-mailbox descriptor property defining Rx channel
+
+Sub-mailbox Descriptor Data
+---------------------------
+Each of the above hi6220,mbox-tx and hi6220,mbox-rx properties should have 3
+cells of data that represent the following:
+    Cell #1 (slot_id) - mailbox slot id used either for transmitting
+                        (hi6220,mbox-tx) or for receiving (hi6220,mbox-rx)
+    Cell #2 (dst_irq) - irq identifier index number which used by MCU.
+    Cell #3 (ack_irq) - irq identifier index number with generating a tx/rx
+                        interrupt to application processor, mailbox driver
+                        used this id to acknowledge interrupt.
+
+Example:
+--------
+
+	mailbox: mailbox@F7510000 {
+		#mbox-cells = <1>;
+		compatible = "hisilicon,hi6220-mbox";
+		reg = <0x0 0xF7510000 0x0 0x1000>, /* IPC_S */
+		      <0x0 0x06DFF800 0x0 0x0800>; /* Mailbox */
+		interrupt-parent = <&gic>;
+		interrupts = <GIC_SPI 94 IRQ_TYPE_LEVEL_HIGH>;
+		mbox_stub_clock: mbox_stub_clock {
+			hi6220,mbox-rx = <0 1 10>;
+			hi6220,mbox-tx = <1 0 11>;
+		};
+	};
+
+
+Mailbox client
+===============
+
+"mboxes" and the optional "mbox-names" (please see
+Documentation/devicetree/bindings/mailbox/mailbox.txt for details). Each value
+of the mboxes property should contain a phandle to the mailbox controller
+device node and second argument is the channel index. It must be 0 (hardware
+support only one channel). The equivalent "mbox-names" property value can be
+used to give a name to the communication channel to be used by the client user.
+
+Example:
+--------
+
+	stub_clock: stub_clock {
+		compatible = "hisilicon,hi6220-stub-clk";
+		hisilicon,hi6220-clk-sram = <&sram>;
+		#clock-cells = <1>;
+		mbox-names = "mbox-tx";
+		mboxes = <&mailbox 1>;
+	};
-- 
1.9.1