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+Amlogic Meson MHU Mailbox Driver
+================================
+
+The Amlogic's Meson SoCs Message-Handling-Unit (MHU) is a mailbox controller
+that has 3 independent channels/links to communicate with remote processor(s).
+MHU links are hardwired on a platform. A link raises interrupt for any
+received data. However, there is no specified way of knowing if the sent
+data has been read by the remote. This driver assumes the sender polls
+STAT register and the remote clears it after having read the data.
+
+Mailbox Device Node:
+====================
+
+Required properties:
+--------------------
+- compatible: Shall be "amlogic,meson-gxbb-mhu"
+- reg: Contains the mailbox register address range (base
+ address and length)
+- #mbox-cells Shall be 1 - the index of the channel needed.
+- interrupts: Contains the interrupt information corresponding to
+ each of the 2 links of MHU.
+
+Example:
+--------
+
+ mailbox: mailbox@c883c404 {
+ #mbox-cells = <1>;
+ compatible = "amlogic,meson-gxbb-mhu";
+ reg = <0 0xc883c404 0 0x4c>;
+ interrupts = <0 208 IRQ_TYPE_EDGE_RISING>,
+ <0 209 IRQ_TYPE_EDGE_RISING>,
+ <0 210 IRQ_TYPE_EDGE_RISING>;
+ #mbox-cells = <1>;
+ };