| * Renesas R-Car GyroADC device driver |
| |
| The GyroADC block is a reduced SPI block with up to 8 chipselect lines, |
| which supports the SPI protocol of a selected few SPI ADCs. The SPI ADCs |
| are sampled by the GyroADC block in a round-robin fashion and the result |
| presented in the GyroADC registers. |
| |
| Required properties: |
| - compatible: Should be "<soc-specific>", "renesas,rcar-gyroadc". |
| The <soc-specific> should be one of: |
| renesas,r8a7791-gyroadc - for the GyroADC block present |
| in r8a7791 SoC |
| renesas,r8a7792-gyroadc - for the GyroADC with interrupt |
| block present in r8a7792 SoC |
| - reg: Address and length of the register set for the device |
| - clocks: References to all the clocks specified in the clock-names |
| property as specified in |
| Documentation/devicetree/bindings/clock/clock-bindings.txt. |
| - clock-names: Shall contain "fck". The "fck" is the GyroADC block clock. |
| - power-domains: Must contain a reference to the PM domain, if available. |
| - #address-cells: Should be <1> (setting for the subnodes) for all ADCs |
| except for "fujitsu,mb88101a". Should be <0> (setting for |
| only subnode) for "fujitsu,mb88101a". |
| - #size-cells: Should be <0> (setting for the subnodes) |
| |
| Sub-nodes: |
| You must define subnode(s) which select the connected ADC type and reference |
| voltage for the GyroADC channels. |
| |
| Required properties for subnodes: |
| - compatible: Should be either of: |
| "fujitsu,mb88101a" |
| - Fujitsu MB88101A compatible mode, |
| 12bit sampling, up to 4 channels can be sampled in |
| round-robin fashion. One Fujitsu chip supplies four |
| GyroADC channels with data as it contains four ADCs |
| on the chip and thus for 4-channel operation, single |
| MB88101A is required. The Cx chipselect lines of the |
| MB88101A connect directly to two CHS lines of the |
| GyroADC, no demuxer is required. The data out line |
| of each MB88101A connects to a shared input pin of |
| the GyroADC. |
| "ti,adcs7476" or "ti,adc121" or "adi,ad7476" |
| - TI ADCS7476 / TI ADC121 / ADI AD7476 compatible mode, |
| 15bit sampling, up to 8 channels can be sampled in |
| round-robin fashion. One TI/ADI chip supplies single |
| ADC channel with data, thus for 8-channel operation, |
| 8 chips are required. A 3:8 chipselect demuxer is |
| required to connect the nCS line of the TI/ADI chips |
| to the GyroADC, while MISO line of each TI/ADI ADC |
| connects to a shared input pin of the GyroADC. |
| "maxim,max1162" or "maxim,max11100" |
| - Maxim MAX1162 / Maxim MAX11100 compatible mode, |
| 16bit sampling, up to 8 channels can be sampled in |
| round-robin fashion. One Maxim chip supplies single |
| ADC channel with data, thus for 8-channel operation, |
| 8 chips are required. A 3:8 chipselect demuxer is |
| required to connect the nCS line of the MAX chips |
| to the GyroADC, while MISO line of each Maxim ADC |
| connects to a shared input pin of the GyroADC. |
| - reg: Should be the number of the analog input. Should be present |
| for all ADCs except "fujitsu,mb88101a". |
| - vref-supply: Reference to the channel reference voltage regulator. |
| |
| Example: |
| vref_max1162: regulator-vref-max1162 { |
| compatible = "regulator-fixed"; |
| |
| regulator-name = "MAX1162 Vref"; |
| regulator-min-microvolt = <4096000>; |
| regulator-max-microvolt = <4096000>; |
| }; |
| |
| adc@e6e54000 { |
| compatible = "renesas,r8a7791-gyroadc", "renesas,rcar-gyroadc"; |
| reg = <0 0xe6e54000 0 64>; |
| clocks = <&mstp9_clks R8A7791_CLK_GYROADC>; |
| clock-names = "fck"; |
| power-domains = <&sysc R8A7791_PD_ALWAYS_ON>; |
| |
| pinctrl-0 = <&adc_pins>; |
| pinctrl-names = "default"; |
| |
| #address-cells = <1>; |
| #size-cells = <0>; |
| |
| adc@0 { |
| reg = <0>; |
| compatible = "maxim,max1162"; |
| vref-supply = <&vref_max1162>; |
| }; |
| |
| adc@1 { |
| reg = <1>; |
| compatible = "maxim,max1162"; |
| vref-supply = <&vref_max1162>; |
| }; |
| }; |