M7350/kernel/Documentation/devicetree/bindings/spi/qcom,spi-qup.txt
2024-09-09 08:57:42 +00:00

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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.
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";
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;
};
};