| Message ID | 1406205921-7452-3-git-send-email-svarbanov@mm-sol.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/24/2014 05:45 AM, Stanimir Varbanov wrote: > Document DT bindings used to describe the Qualcomm SPMI PMICs. > Currently the SPMI PMICs supported are pm8941, pm8841 and pma8084. > > Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com> (...) > +Required properties for peripheral child nodes: > +- compatible: Should contain "qcom,pm8xxx-xxx", where "xxx" is > + peripheral name. The "pm8xxx" can be any of supported PMICs, > + see example below. I don't think that this binding document should be imposing any formatting restrictions on the compatible strings for QPNP peripheral drivers. The QPNP peripheral drivers in the downstream msm-3.10 tree [1] do not specify per-PMIC compatible strings. This is because ideally, a given QPNP peripheral represents a hardware block that is identical in interface and operation between PMICs. These peripheral drivers determine the base address for a given device instance via device tree reg and reg-names properties. In order for this to continue to work with the pm8xxx-spmi driver, some mechanism will need to be introduced which creates resource structs for the non-memory-mappable SPMI base addresses. One possible solution is currently being discussed in another thread [2]. This document will need to be updated to show the child node reg property scheme once a solution is reached. (...) > +Example: > + > + pm8941@0 { > + compatible = "qcom,pm8941"; > + reg = <0x0 SPMI_USID>; > + > + rtc { > + compatible = "qcom,pm8941-rtc"; > + interrupts = <0x0 0x61 0x1 IRQ_TYPE_EDGE_RISING>; > + interrupt-names = "alarm"; > + }; > + }; Can you please expand your example to include the second SID for the PM8941 chip? That way, it will be clear that each PMIC needs two DT nodes; one for each SID. Thanks, David Collins [1]: https://www.codeaurora.org/cgit/quic/la/kernel/msm-3.10/tree/?h=msm-3.10 [2]: https://lkml.org/lkml/2014/7/29/252
On 07/30/2014 01:23 AM, David Collins wrote: > On 07/24/2014 05:45 AM, Stanimir Varbanov wrote: >> Document DT bindings used to describe the Qualcomm SPMI PMICs. >> Currently the SPMI PMICs supported are pm8941, pm8841 and pma8084. >> >> Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com> > > (...) >> +Required properties for peripheral child nodes: >> +- compatible: Should contain "qcom,pm8xxx-xxx", where "xxx" is >> + peripheral name. The "pm8xxx" can be any of supported PMICs, >> + see example below. > > I don't think that this binding document should be imposing any formatting > restrictions on the compatible strings for QPNP peripheral drivers. The > QPNP peripheral drivers in the downstream msm-3.10 tree [1] do not specify > per-PMIC compatible strings. This is because ideally, a given QPNP > peripheral represents a hardware block that is identical in interface and > operation between PMICs. > Isn't "hardware block that is identical in interface and operation between PMICs" exactly the meaning of *compatible* property? No *compatible* property, no platform device. We must have this property for every peripheral driver. > These peripheral drivers determine the base address for a given device > instance via device tree reg and reg-names properties. In order for this > to continue to work with the pm8xxx-spmi driver, some mechanism will need > to be introduced which creates resource structs for the > non-memory-mappable SPMI base addresses. One possible solution is > currently being discussed in another thread [2]. This document will need > to be updated to show the child node reg property scheme once a solution > is reached. > That's correct. If we reach the "reg" solution this binding document must be changed. > (...) >> +Example: >> + >> + pm8941@0 { >> + compatible = "qcom,pm8941"; >> + reg = <0x0 SPMI_USID>; >> + >> + rtc { >> + compatible = "qcom,pm8941-rtc"; >> + interrupts = <0x0 0x61 0x1 IRQ_TYPE_EDGE_RISING>; >> + interrupt-names = "alarm"; >> + }; >> + }; > > Can you please expand your example to include the second SID for the > PM8941 chip? That way, it will be clear that each PMIC needs two DT > nodes; one for each SID. Sure, will do.
On 07/31/2014 01:58 AM, Stanimir Varbanov wrote: > On 07/30/2014 01:23 AM, David Collins wrote: >> On 07/24/2014 05:45 AM, Stanimir Varbanov wrote: >>> Document DT bindings used to describe the Qualcomm SPMI PMICs. >>> Currently the SPMI PMICs supported are pm8941, pm8841 and pma8084. >>> >>> Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com> >> >> (...) >>> +Required properties for peripheral child nodes: >>> +- compatible: Should contain "qcom,pm8xxx-xxx", where "xxx" is >>> + peripheral name. The "pm8xxx" can be any of supported PMICs, >>> + see example below. >> >> I don't think that this binding document should be imposing any formatting >> restrictions on the compatible strings for QPNP peripheral drivers. The >> QPNP peripheral drivers in the downstream msm-3.10 tree [1] do not specify >> per-PMIC compatible strings. This is because ideally, a given QPNP >> peripheral represents a hardware block that is identical in interface and >> operation between PMICs. >> > > Isn't "hardware block that is identical in interface and operation > between PMICs" exactly the meaning of *compatible* property? > > No *compatible* property, no platform device. We must have this property > for every peripheral driver. I am not suggesting that we remove the compatible property for peripheral device nodes. I agree that these nodes need to have a compatible property. My concern is that this binding document should not require the peripheral nodes to have compatible property values that are PMIC specific. For example, in the downstream msm-3.10 branch the power-on peripheral uses the same compatible string regardless of what PMIC the peripheral is found on: "qcom,qpnp-power-on" [1]. There is no reason for the driver to care about what PMIC the peripheral is found on. Therefore, it does not make sense to force it to support compatible strings like "qcom,pm8941-power-on", "qcom,pm8841-power-on", "qcom,pma8084-power-on", etc. Every QPNP PMIC peripheral has its own set of type and version registers that allow software to auto-detect its capabilities at runtime. Take care, David [1]: https://www.codeaurora.org/cgit/quic/la/kernel/msm-3.10/tree/Documentation/devicetree/bindings/platform/msm/qpnp-power-on.txt?h=msm-3.10
diff --git a/Documentation/devicetree/bindings/mfd/qcom,pm8xxx-spmi.txt b/Documentation/devicetree/bindings/mfd/qcom,pm8xxx-spmi.txt new file mode 100644 index 0000000..2b7f5b6 --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/qcom,pm8xxx-spmi.txt @@ -0,0 +1,49 @@ + Qualcomm PM8XXX SPMI PMICs multi-function device bindings + +The Qualcomm PM8XXX series presently includes PM8941, PM8841 and PMA8084 +PMICs. These PMICs use a QPNP scheme through SPMI interface. +QPNP is effectively a partitioning scheme for dividing the SPMI extended +register space up into logical pieces, and set of fixed register +locations/definitions within these regions, with some of these regions +specifically used for interrupt handling. + +The QPNP PMICs are used with the Qualcomm Snapdragon series SoCs, and are +interfaced to the chip via the SPMI (System Power Management Interface) bus. +Support for multiple independent functions are implemented by splitting the +16-bit SPMI slave address space into 256 smaller fixed-size regions, 256 bytes +each. A function can consume one or more of these fixed-size register regions. + +Required properties: +- compatible: Should contain one of: + "qcom,pm8941" + "qcom,pm8841" + "qcom,pma8084" +- reg: Specifies the SPMI USID slave address for this device. + For more information see: + Documentation/devicetree/bindings/spmi/spmi.txt + +Required properties for peripheral child nodes: +- compatible: Should contain "qcom,pm8xxx-xxx", where "xxx" is + peripheral name. The "pm8xxx" can be any of supported PMICs, + see example below. + +Optional properties for peripheral child nodes: +- interrupts: Interrupts are specified as a 4-tuple. For more information + see: + Documentation/devicetree/bindings/spmi/qcom,spmi-pmic-arb.txt +- interrupt-names: Corresponding interrupt name to the interrupts property + +Each child node represents a function of the PMIC. + +Example: + + pm8941@0 { + compatible = "qcom,pm8941"; + reg = <0x0 SPMI_USID>; + + rtc { + compatible = "qcom,pm8941-rtc"; + interrupts = <0x0 0x61 0x1 IRQ_TYPE_EDGE_RISING>; + interrupt-names = "alarm"; + }; + };
Document DT bindings used to describe the Qualcomm SPMI PMICs. Currently the SPMI PMICs supported are pm8941, pm8841 and pma8084. Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com> --- .../devicetree/bindings/mfd/qcom,pm8xxx-spmi.txt | 49 ++++++++++++++++++++ 1 files changed, 49 insertions(+), 0 deletions(-) create mode 100644 Documentation/devicetree/bindings/mfd/qcom,pm8xxx-spmi.txt