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authorJohn Klug <john.klug@multitech.com>2019-05-10 17:10:10 -0500
committerJohn Klug <john.klug@multitech.com>2019-05-10 17:10:10 -0500
commit4f5efcb39b25a2a9c24c36c467e7f14ce6e818a5 (patch)
treed3e4c704b655ca16f2686c7696d3dac070131a3a /README
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Device Tree Overlay Example1.0.0
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+This is the device tree overlay(s) and its make.
+
+The purpose of the overlay is to define the system
+for the mts-io driver and/or mtac drivers.
+
+The correct overlay for the system is loaded at
+runtime before loading the mts-io driver. A method
+for doing this is the device tree configfs driver.
+
+See this for the format of an overlay:
+
+https://www.kernel.org/doc/Documentation/devicetree/overlay-notes.txt
+
+Note that as of 10 May 2019, no overlays have been
+released.
+
+The biggest flaw in overlays, is the inablitiy to use
+the phandle described in an alias in the boot
+time device tree in an overlay, so it appears
+to be impossible to reference nodes in the main
+device tree in any shorthand method. For instance, it
+is common to reference a "pio" in device tree to
+use a PIO with GPIO. For example, it does not appear
+to be possible to use &pioC in the overlay without
+redefining it.