| Message ID | 20180820063953.6866-2-vkoul@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v4,1/2] dt-bindings: i2c: Add binding for Qualcomm CCI I2C controller | expand |
On 21-08-18, 08:12, Rob Herring wrote: > Hit send too soon... > > On Tue, Aug 21, 2018 at 8:11 AM Rob Herring <robh@kernel.org> wrote: > > > > On Tue, Aug 21, 2018 at 4:28 AM Vinod <vkoul@kernel.org> wrote: > > > > > > On 20-08-18, 13:18, Rob Herring wrote: > > > > On Mon, Aug 20, 2018 at 12:09:52PM +0530, Vinod Koul wrote: > > > > > > > > +PROPERTIES: > > > > > + > > > > > +- compatible: > > > > > + Usage: required > > > > > + Value type: <string> > > > > > + Definition: must be one of: > > > > > + "qcom,msm-8916-cci" > > > > > + "qcom,msm-8996-cci" > > > > > > > > I think everywhere else is 'msm8916' and 'msm8996'. > > > > > > Quick grep told me that is the case, so will update. > > > > > > > > +SUBNODES: > > > > > + > > > > > +The CCI provides I2C masters for one or two i2c busses, described as > > > > > +subdevices named "i2c-bus0" and "i2c-bus1". > > > > > > > > Use a unit-address and reg property with 0 and 1 here. > > > > > > Am not sure I understood that properly, still learning DT nuisances, > > > care to elaborate a bit please. > > > > Node names are supposed to be standard (there's a list in the DT spec) > > and i2c-bus is for cases where the controller is not the bus parent. > > So you just need it to look like this: > > > > i2c-bus@0 { > > reg = <0>; > > ... > > }; > > > > i2c-bus@1 { > > reg = <1>; > > ... > > }; > > > > It's similar to how i2c muxes are done where you have multiple > > downstream i2c buses. Following this will enable some i2c bus checks > > in dtc (current master, not kernel copy yet) as node names are the > > only way > > ...we can match i2c buses in a generic way. I tried i2c-bus@0, but wasn't able to do it properly, let me try again with this approach. It does sound great to me, will update.. -- ~Vinod
diff --git a/Documentation/devicetree/bindings/i2c/i2c-qcom-cci.txt b/Documentation/devicetree/bindings/i2c/i2c-qcom-cci.txt new file mode 100644 index 000000000000..b7f4240ce5c8 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-qcom-cci.txt @@ -0,0 +1,83 @@ +Qualcomm Camera Control Interface (CCI) I2C controller + +PROPERTIES: + +- compatible: + Usage: required + Value type: <string> + Definition: must be one of: + "qcom,msm-8916-cci" + "qcom,msm-8996-cci" + +- reg + Usage: required + Value type: <prop-encoded-array> + Definition: base address CCI I2C controller and length of memory + mapped region. + +- interrupts: + Usage: required + Value type: <prop-encoded-array> + Definition: specifies the CCI I2C interrupt. The format of the + specifier is defined by the binding document describing + the node's interrupt parent. + +- clocks: + Usage: required + Value type: <prop-encoded-array> + Definition: a list of phandle, should contain an entry for each + entries in clock-names. + +- clock-names + Usage: required + Value type: <string> + Definition: a list of clock names, must include these entries: + "mmss_mmagic_ahb" - on "qcom,msm-8996-cci" only; + "camss_top_ahb"; + "cci_ahb"; + "cci"; + "camss_ahb"; + +- power-domains + Usage: required for "qcom,msm-8996-cci" + Value type: <prop-encoded-array> + Definition: + +SUBNODES: + +The CCI provides I2C masters for one or two i2c busses, described as +subdevices named "i2c-bus0" and "i2c-bus1". + +PROPERTIES: + +- clock-frequency: + Usage: optional + Value type: <u32> + Definition: Desired I2C bus clock frequency in Hz, defaults to 100 + kHz if omitted. + +Example: + + cci@a0c000 { + compatible = "qcom,msm-8996-cci"; + #address-cells = <1>; + #size-cells = <0>; + reg = <0xa0c000 0x1000>; + interrupts = <GIC_SPI 295 IRQ_TYPE_EDGE_RISING>; + clocks = <&mmcc MMSS_MMAGIC_AHB_CLK>, + <&mmcc CAMSS_TOP_AHB_CLK>, + <&mmcc CAMSS_CCI_AHB_CLK>, + <&mmcc CAMSS_CCI_CLK>, + <&mmcc CAMSS_AHB_CLK>; + clock-names = "mmss_mmagic_ahb", + "camss_top_ahb", + "cci_ahb", + "cci", + "camss_ahb"; + i2c-bus0 { + clock-frequency = <400000>; + }; + i2c-bus1 { + clock-frequency = <400000>; + }; + };