Re: [PATCH v5 5/5] usb: dwc3: rockchip: add devicetree bindings documentation

From: William Wu
Date: Thu Jun 30 2016 - 21:28:12 EST


Dear Heiko,

On 06/30/2016 08:15 PM, Heiko Stuebner wrote:
Hi William,

Am Donnerstag, 30. Juni 2016, 19:16:40 schrieb William Wu:
This patch adds the devicetree documentation required for Rockchip
USB3.0 core wrapper consisting of USB3.0 IP from Synopsys.

It supports DRD mode, and could operate in device mode (SS, HS, FS)
and host mode (SS, HS, FS, LS).

Signed-off-by: William Wu <william.wu@xxxxxxxxxxxxxx>
---
Changes in v5:
- rename clock-names, and remove unnecessary clocks (Heiko)

Changes in v4:
- modify commit log, and add phy documentation location (Sergei)

Changes in v3:
- add dwc3 address (balbi)

Changes in v2:
- add rockchip,dwc3.txt to Documentation/devicetree/bindings/ (balbi,
Brian)

.../devicetree/bindings/usb/rockchip,dwc3.txt | 40
++++++++++++++++++++++ 1 file changed, 40 insertions(+)
create mode 100644
Documentation/devicetree/bindings/usb/rockchip,dwc3.txt

diff --git a/Documentation/devicetree/bindings/usb/rockchip,dwc3.txt
b/Documentation/devicetree/bindings/usb/rockchip,dwc3.txt new file mode
100644
index 0000000..9c85e19
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/rockchip,dwc3.txt
@@ -0,0 +1,40 @@
+Rockchip SuperSpeed DWC3 USB SoC controller
+
+Required properties:
+- compatible: should contain "rockchip,rk3399-dwc3" for rk3399 SoC
+- clocks: A list of phandle + clock-specifier pairs for the
+ clocks listed in clock-names
+- clock-names: Should contain the following:
+ "ref_clk" Controller reference clk, have to be 24 MHz
+ "suspend_clk" Controller suspend clk, have to be 24 MHz or 32 KHz
+ "bus_clk_otg0"Master/Core clock, have to be >= 62.5 MHz for SS
+ operation and >= 60MHz for HS operation
why is it called "bus_clk_otg0" not just simply "bus_clk". As far as I
understand it (and see it in the TRM), you have two dwc3 controllers
(otg0 and otg1) and clock-names are always meant from the perspective of
the individual ip-block. So a devicetree would have:

usbdrd3_0: usb@fe800000 {
compatible = "rockchip,rk3399-dwc3";
clocks = <&cru SCLK_USB3OTG0_REF>, <&cru SCLK_USB3OTG0_SUSPEND>,
<&cru ACLK_USB3OTG0>, <&cru ACLK_USB3_GRF>;
clock-names = "ref_clk", "suspend_clk",
"bus_clk", "grf_clk";
...
};

usbdrd3_1: usb@fe900000 {
compatible = "rockchip,rk3399-dwc3";
clocks = <&cru SCLK_USB3OTG1_REF>, <&cru SCLK_USB3OTG1_SUSPEND>,
<&cru ACLK_USB3OTG1>, <&cru ACLK_USB3_GRF>;
clock-names = "ref_clk", "suspend_clk",
"bus_clk", "grf_clk";
...
};


The rest looks really nice now.
Ah, it looks very goog to me. I'll fix it immediately.
Thank you very much!


Heiko

+ "grf_clk" Controller grf clk
+
+Required child node:
+A child node must exist to represent the core DWC3 IP block. The name of
+the node is not important. The content of the node is defined in
dwc3.txt. +
+Phy documentation is provided in the following places:
+Documentation/devicetree/bindings/phy/rockchip,dwc3-usb-phy.txt
+
+Example device nodes:
+
+ usbdrd3_0: usb@fe800000 {
+ compatible = "rockchip,rk3399-dwc3";
+ clocks = <&cru SCLK_USB3OTG0_REF>, <&cru SCLK_USB3OTG0_SUSPEND>,
+ <&cru ACLK_USB3OTG0>, <&cru ACLK_USB3_GRF>;
+ clock-names = "ref_clk", "suspend_clk",
+ "bus_clk_otg0", "grf_clk";
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+ status = "disabled";
+ usbdrd_dwc3_0: dwc3@fe800000 {
+ compatible = "snps,dwc3";
+ reg = <0x0 0xfe800000 0x0 0x100000>;
+ interrupts = <GIC_SPI 105 IRQ_TYPE_LEVEL_HIGH>;
+ dr_mode = "otg";
+ status = "disabled";
+ };
+ };
--
1.9.1