Re: [PATCH 01/10] dt-bindings: usb: add support for dwc3 controller on HiSilicon SoCs

From: Chen Yu
Date: Fri Nov 16 2018 - 21:29:46 EST


Hi,

On 2018/11/13 0:02, Rob Herring wrote:
> On Sat, Oct 27, 2018 at 05:58:11PM +0800, Yu Chen wrote:
>> This patch adds binding descriptions to support the dwc3 controller
>> on HiSilicon SoCs and boards like the HiKey960.
>>
>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
>> Cc: Mark Rutland <mark.rutland@xxxxxxx>
>> Cc: John Stultz <john.stultz@xxxxxxxxxx>
>> Signed-off-by: Yu Chen <chenyu56@xxxxxxxxxx>
>> ---
>> .../devicetree/bindings/usb/dwc3-hisi.txt | 53 ++++++++++++++++++++++
>> 1 file changed, 53 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/usb/dwc3-hisi.txt
>>
>> diff --git a/Documentation/devicetree/bindings/usb/dwc3-hisi.txt b/Documentation/devicetree/bindings/usb/dwc3-hisi.txt
>> new file mode 100644
>> index 000000000000..e715e7b1c324
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/usb/dwc3-hisi.txt
>> @@ -0,0 +1,53 @@
>> +HiSilicon DWC3 USB SoC controller
>> +
>> +This file documents the parameters for the dwc3-hisi driver.
>> +
>> +Required properties:
>> +- compatible: should be "hisilicon,hi3660-dwc3"
>> +- clocks: A list of phandle + clock-specifier pairs for the
>> + clocks listed in clock-names
>> +- clock-names: Specify clock names
>> +- resets: list of phandle and reset specifier pairs.
>> +
>> +Sub-nodes:
>> +The dwc3 core should be added as subnode to HiSilicon DWC3 as shown in the
>> +example below. The DT binding details of dwc3 can be found in:
>> +Documentation/devicetree/bindings/usb/dwc3.txt
>
> If you only have clocks and resets and no glue registers, then you
> don't need a sub-node. Just make the controller one node.
>

In dwc3 glue driverïthe controller driver usually probed by call of_platform_populate
which will search the child node of glue driver.
The code of function of_platform_populate is as below:

for_each_child_of_node(root, child) {
rc = of_platform_bus_create(child, matches, lookup, parent, true);
if (rc) {
of_node_put(child);
break;
}
}

So I think the controller node should be a sub-node.

>> +
>> +Example:
>> + usb3: hisi_dwc3 {
>> + compatible = "hisilicon,hi3660-dwc3";
>> + #address-cells = <2>;
>> + #size-cells = <2>;
>> + ranges;
>> +
>> + clocks = <&crg_ctrl HI3660_CLK_ABB_USB>,
>> + <&crg_ctrl HI3660_ACLK_GATE_USB3OTG>;
>> + clock-names = "clk_usb3phy_ref", "aclk_usb3otg";
>> + assigned-clocks = <&crg_ctrl HI3660_ACLK_GATE_USB3OTG>;
>> + assigned-clock-rates = <229000000>;
>> + resets = <&crg_rst 0x90 8>,
>> + <&crg_rst 0x90 7>,
>> + <&crg_rst 0x90 6>,
>> + <&crg_rst 0x90 5>;
>> +
>> + dwc3: dwc3@ff100000 {
>
> usb@...
>
>> + compatible = "snps,dwc3";
>> + reg = <0x0 0xff100000 0x0 0x100000>;
>> + interrupts = <0 159 4>, <0 161 4>;
>> + phys = <&usb_phy>;
>> + phy-names = "usb3-phy";
>> + dr_mode = "otg";
>> + maximum-speed = "super-speed";
>> + phy_type = "utmi";
>> + snps,dis-del-phy-power-chg-quirk;
>> + snps,lfps_filter_quirk;
>> + snps,dis_u2_susphy_quirk;
>> + snps,dis_u3_susphy_quirk;
>> + snps,tx_de_emphasis_quirk;
>> + snps,tx_de_emphasis = <1>;
>> + snps,dis_enblslpm_quirk;
>> + snps,gctl-reset-quirk;
>> + extcon = <&hisi_hikey_usb>;
>> + };
>> + };
>> --
>> 2.15.0-rc2
>>
>
>
> .
>