[PATCH v4 4/5] drivers: bus: Add Renesas Bus State Controller (BSC) DT Bindings

Geert Uytterhoeven
2015-01-26T16:16:16Z

The bindings for the BSC extend the bindings for "simple-pm-bus".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v4:
- New, extracted from simple-pm-bus.txt in v3.
---
.../devicetree/bindings/bus/renesas,bsc.txt | 46 ++++++++++++++++++++++
1 file changed, 46 insertions(+)
create mode 100644 Documentation/devicetree/bindings/bus/renesas,bsc.txt

diff --git a/Documentation/devicetree/bindings/bus/renesas,bsc.txt b/Documentation/devicetree/bindings/bus/renesas,bsc.txt
new file mode 100644
index 0000000000000000..90e94726943772c4
--- /dev/null
+++ b/Documentation/devicetree/bindings/bus/renesas,bsc.txt
@@ -0,0 +1,46 @@
+Renesas Bus State Controller (BSC)
+==================================
+
+The Renesas Bus State Controller (BSC, sometimes called "LBSC within Bus
+Bridge", or "External Bus Interface") can be found in several Renesas ARM SoCs.
+It provides an external bus for connecting multiple external devices to the
+SoC, driving several chip select lines, for e.g. NOR FLASH, Ethernet and USB.
+
+While the BSC is a fairly simple memory-mapped bus, it may be part of a PM
+domain, and may have a gateable functional clock.
+Before a device connected to the BSC can be accessed, the PM domain
+containing the BSC must be powered on, and the functional clock
+driving the BSC must be enabled.
+
+The bindings for the BSC extend the bindings for "simple-pm-bus".
+
+
+Required properties
+ - compatible: Must contain an SoC-specific value, and "renesas,bsc" and
+ "simple-pm-bus" as fallbacks.
+ SoC-specific values can be:
+ "renesas,bsc-r8a73a4" for R-Mobile APE6 (r8a73a4)
+ "renesas,bsc-sh73a0" for SH-Mobile AG5 (sh73a0)
+ - #address-cells, #size-cells, ranges: Must describe the mapping between
+ parent address and child address spaces.
+ - reg: Must contain the base address and length to access the bus controller.
+
+Optional properties:
+ - interrupts: Must contain a reference to the BSC interrupt, if available.
+ - clocks: Must contain a reference to the functional clock, if available.
+ - power-domains: Must contain a reference to the PM domain, if available.
+
+
+Example:
+
+ bsc: bus at fec10000 {
+ compatible = "renesas,bsc-sh73a0", "renesas,bsc",
+ "simple-pm-bus";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 0 0x20000000>;
+ reg = <0xfec10000 0x400>;
+ interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&zb_clk>;
+ power-domains = <&pd_a4s>;
+ };
--
1.9.1