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Diffstat (limited to 'Documentation/devicetree/bindings/clock/ti/dra7-atl.txt')
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diff --git a/Documentation/devicetree/bindings/clock/ti/dra7-atl.txt b/Documentation/devicetree/bindings/clock/ti/dra7-atl.txt new file mode 100644 index 000000000..68504079f --- /dev/null +++ b/Documentation/devicetree/bindings/clock/ti/dra7-atl.txt @@ -0,0 +1,94 @@ +Device Tree Clock bindings for ATL (Audio Tracking Logic) of DRA7 SoC. + +The ATL IP is used to generate clock to be used to synchronize baseband and +audio codec. A single ATL IP provides four ATL clock instances sharing the same +functional clock but can be configured to provide different clocks. +ATL can maintain a clock averages to some desired frequency based on the bws/aws +signals - can compensate the drift between the two ws signal. + +In order to provide the support for ATL and its output clocks (which can be used +internally within the SoC or external components) two sets of bindings is needed: + +Clock tree binding: +This binding uses the common clock binding[1]. +To be able to integrate the ATL clocks with DT clock tree. +Provides ccf level representation of the ATL clocks to be used by drivers. +Since the clock instances are part of a single IP this binding is used as a node +for the DT clock tree, the IP driver is needed to handle the actual configuration +of the IP. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- compatible : shall be "ti,dra7-atl-clock" +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : link phandles to functional clock of ATL + +Binding for the IP driver: +This binding is used to configure the IP driver which is going to handle the +configuration of the IP for the ATL clock instances. + +Required properties: +- compatible : shall be "ti,dra7-atl" +- reg : base address for the ATL IP +- ti,provided-clocks : List of phandles to the clocks associated with the ATL +- clocks : link phandles to functional clock of ATL +- clock-names : Shall be set to "fck" +- ti,hwmods : Shall be set to "atl" + +Optional properties: +Configuration of ATL instances: +- atl{0/1/2/3} { + - bws : Baseband word select signal selection + - aws : Audio word select signal selection +}; + +For valid word select signals, see the dt-bindings/clock/ti-dra7-atl.h include +file. + +Examples: +/* clock bindings for atl provided clocks */ +atl_clkin0_ck: atl_clkin0_ck { + #clock-cells = <0>; + compatible = "ti,dra7-atl-clock"; + clocks = <&atl_gfclk_mux>; +}; + +atl_clkin1_ck: atl_clkin1_ck { + #clock-cells = <0>; + compatible = "ti,dra7-atl-clock"; + clocks = <&atl_gfclk_mux>; +}; + +atl_clkin2_ck: atl_clkin2_ck { + #clock-cells = <0>; + compatible = "ti,dra7-atl-clock"; + clocks = <&atl_gfclk_mux>; +}; + +atl_clkin3_ck: atl_clkin3_ck { + #clock-cells = <0>; + compatible = "ti,dra7-atl-clock"; + clocks = <&atl_gfclk_mux>; +}; + +/* binding for the IP */ +atl: atl@4843c000 { + compatible = "ti,dra7-atl"; + reg = <0x4843c000 0x3ff>; + ti,hwmods = "atl"; + ti,provided-clocks = <&atl_clkin0_ck>, <&atl_clkin1_ck>, + <&atl_clkin2_ck>, <&atl_clkin3_ck>; + clocks = <&atl_gfclk_mux>; + clock-names = "fck"; +}; + +#include <dt-bindings/clock/ti-dra7-atl.h> + +&atl { + + atl2 { + bws = <DRA7_ATL_WS_MCASP2_FSX>; + aws = <DRA7_ATL_WS_MCASP3_FSX>; + }; +}; |