From: Rafał Miłecki <rafal@xxxxxxxxxx>
USB 2.0 PHY is a hardware block that happens to use two registers from
the CRU block to setup a single PLL. It's not part of the CRU or DMU
and so its binding shouldn't cover the whole DMU.
The correct way of handling this is to reference CRU block node using a
syscon. Document that & deprecate the old way.
Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
---
V2: use syscon@ in example (thanks Ray)
---
.../devicetree/bindings/phy/bcm-ns-usb2-phy.txt | 27 ++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)
diff --git a/Documentation/devicetree/bindings/phy/bcm-ns-usb2-phy.txt b/Documentation/devicetree/bindings/phy/bcm-ns-usb2-phy.txt
index a7aee9ea8926..2cafee6b4a8b 100644
--- a/Documentation/devicetree/bindings/phy/bcm-ns-usb2-phy.txt
+++ b/Documentation/devicetree/bindings/phy/bcm-ns-usb2-phy.txt
@@ -2,19 +2,38 @@ Driver for Broadcom Northstar USB 2.0 PHY
Required properties:
- compatible: brcm,ns-usb2-phy
-- reg: iomem address range of DMU (Device Management Unit)
-- reg-names: "dmu", the only needed & supported reg right now
+- syscon-cru: phandle to the CRU (Central Resource Unit) syscon
- clocks: USB PHY reference clock
- clock-names: "phy-ref-clk", the only needed & supported clock right now
+Deprecated:
+
+PHY block should not claim the whole DMU so such a binding has been deprecated.
+It only requires to access few CRU (a DMU subblock) registers and that should be
+handled with a syscon since CRU is a MFD (Multi-Function Device).
+
+- reg: iomem address range of DMU (Device Management Unit)
+- reg-names: "dmu", the only needed & supported reg right now
+
To initialize USB 2.0 PHY driver needs to setup PLL correctly. To do this it
requires passing phandle to the USB PHY reference clock.
Example:
+ dmu@1800c000 {
+ compatible = "simple-bus";
+ ranges = <0 0x1800c000 0x1000>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ cru: syscon@100 {
+ compatible = "syscon", "simple-mfd";
+ reg = <0x100 0x1a4>;
+ };
+ };
+
usb2-phy {
compatible = "brcm,ns-usb2-phy";
- reg = <0x1800c000 0x1000>;
- reg-names = "dmu";
+ syscon-cru = <&cru>;
#phy-cells = <0>;
clocks = <&genpll BCM_NSP_GENPLL_USB_PHY_REF_CLK>;
clock-names = "phy-ref-clk";
--
2.13.7
