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Diffstat (limited to 'Documentation/devicetree/bindings/spi/qcom,spi-qup.txt')
-rw-r--r-- | Documentation/devicetree/bindings/spi/qcom,spi-qup.txt | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/spi/qcom,spi-qup.txt b/Documentation/devicetree/bindings/spi/qcom,spi-qup.txt new file mode 100644 index 000000000..5c090771c --- /dev/null +++ b/Documentation/devicetree/bindings/spi/qcom,spi-qup.txt @@ -0,0 +1,103 @@ +Qualcomm Universal Peripheral (QUP) Serial Peripheral Interface (SPI) + +The QUP core is an AHB slave that provides a common data path (an output FIFO +and an input FIFO) for serial peripheral interface (SPI) mini-core. + +SPI in master mode supports up to 50MHz, up to four chip selects, programmable +data path from 4 bits to 32 bits and numerous protocol variants. + +Required properties: +- compatible: Should contain: + "qcom,spi-qup-v1.1.1" for 8660, 8960 and 8064. + "qcom,spi-qup-v2.1.1" for 8974 and later + "qcom,spi-qup-v2.2.1" for 8974 v2 and later. + +- reg: Should contain base register location and length +- interrupts: Interrupt number used by this controller + +- clocks: Should contain the core clock and the AHB clock. +- clock-names: Should be "core" for the core clock and "iface" for the + AHB clock. + +- #address-cells: Number of cells required to define a chip select + address on the SPI bus. Should be set to 1. +- #size-cells: Should be zero. + +Optional properties: +- spi-max-frequency: Specifies maximum SPI clock frequency, + Units - Hz. Definition as per + Documentation/devicetree/bindings/spi/spi-bus.txt +- num-cs: total number of chipselects +- cs-gpios: should specify GPIOs used for chipselects. + The gpios will be referred to as reg = <index> in the SPI child + nodes. If unspecified, a single SPI device without a chip + select can be used. + +- dmas: Two DMA channel specifiers following the convention outlined + in bindings/dma/dma.txt +- dma-names: Names for the dma channels, if present. There must be at + least one channel named "tx" for transmit and named "rx" for + receive. + +SPI slave nodes must be children of the SPI master node and can contain +properties described in Documentation/devicetree/bindings/spi/spi-bus.txt + +Example: + + spi_8: spi@f9964000 { /* BLSP2 QUP2 */ + + compatible = "qcom,spi-qup-v2"; + #address-cells = <1>; + #size-cells = <0>; + reg = <0xf9964000 0x1000>; + interrupts = <0 102 0>; + spi-max-frequency = <19200000>; + + clocks = <&gcc GCC_BLSP2_QUP2_SPI_APPS_CLK>, <&gcc GCC_BLSP2_AHB_CLK>; + clock-names = "core", "iface"; + + dmas = <&blsp1_bam 13>, <&blsp1_bam 12>; + dma-names = "rx", "tx"; + + pinctrl-names = "default"; + pinctrl-0 = <&spi8_default>; + + device@0 { + compatible = "arm,pl022-dummy"; + #address-cells = <1>; + #size-cells = <1>; + reg = <0>; /* Chip select 0 */ + spi-max-frequency = <19200000>; + spi-cpol; + }; + + device@1 { + compatible = "arm,pl022-dummy"; + #address-cells = <1>; + #size-cells = <1>; + reg = <1>; /* Chip select 1 */ + spi-max-frequency = <9600000>; + spi-cpha; + }; + + device@2 { + compatible = "arm,pl022-dummy"; + #address-cells = <1>; + #size-cells = <1>; + reg = <2>; /* Chip select 2 */ + spi-max-frequency = <19200000>; + spi-cpol; + spi-cpha; + }; + + device@3 { + compatible = "arm,pl022-dummy"; + #address-cells = <1>; + #size-cells = <1>; + reg = <3>; /* Chip select 3 */ + spi-max-frequency = <19200000>; + spi-cpol; + spi-cpha; + spi-cs-high; + }; + }; |