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32ced09d79
Convert the serial slave-device Device Tree binding documentation to json-schema, and incorporate it into the generic serial bindings. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Matthias Brugger <mbrugger@suse.com> Signed-off-by: Rob Herring <robh@kernel.org>
88 lines
2.8 KiB
Plaintext
88 lines
2.8 KiB
Plaintext
* Qualcomm QCA7000
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The QCA7000 is a serial-to-powerline bridge with a host interface which could
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be configured either as SPI or UART slave. This configuration is done by
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the QCA7000 firmware.
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(a) Ethernet over SPI
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In order to use the QCA7000 as SPI device it must be defined as a child of a
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SPI master in the device tree.
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Required properties:
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- compatible : Should be "qca,qca7000"
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- reg : Should specify the SPI chip select
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- interrupts : The first cell should specify the index of the source
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interrupt and the second cell should specify the trigger
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type as rising edge
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- spi-cpha : Must be set
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- spi-cpol : Must be set
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Optional properties:
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- spi-max-frequency : Maximum frequency of the SPI bus the chip can operate at.
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Numbers smaller than 1000000 or greater than 16000000
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are invalid. Missing the property will set the SPI
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frequency to 8000000 Hertz.
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- qca,legacy-mode : Set the SPI data transfer of the QCA7000 to legacy mode.
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In this mode the SPI master must toggle the chip select
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between each data word. In burst mode these gaps aren't
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necessary, which is faster. This setting depends on how
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the QCA7000 is setup via GPIO pin strapping. If the
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property is missing the driver defaults to burst mode.
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The MAC address will be determined using the optional properties
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defined in ethernet.txt.
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SPI Example:
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/* Freescale i.MX28 SPI master*/
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ssp2: spi@80014000 {
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#address-cells = <1>;
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#size-cells = <0>;
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compatible = "fsl,imx28-spi";
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pinctrl-names = "default";
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pinctrl-0 = <&spi2_pins_a>;
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qca7000: ethernet@0 {
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compatible = "qca,qca7000";
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reg = <0x0>;
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interrupt-parent = <&gpio3>; /* GPIO Bank 3 */
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interrupts = <25 0x1>; /* Index: 25, rising edge */
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spi-cpha; /* SPI mode: CPHA=1 */
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spi-cpol; /* SPI mode: CPOL=1 */
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spi-max-frequency = <8000000>; /* freq: 8 MHz */
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local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
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};
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};
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(b) Ethernet over UART
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In order to use the QCA7000 as UART slave it must be defined as a child of a
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UART master in the device tree. It is possible to preconfigure the UART
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settings of the QCA7000 firmware, but it's not possible to change them during
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runtime.
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Required properties:
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- compatible : Should be "qca,qca7000"
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Optional properties:
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- local-mac-address : see ./ethernet.txt
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- current-speed : current baud rate of QCA7000 which defaults to 115200
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if absent, see also ../serial/serial.yaml
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UART Example:
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/* Freescale i.MX28 UART */
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auart0: serial@8006a000 {
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compatible = "fsl,imx28-auart", "fsl,imx23-auart";
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reg = <0x8006a000 0x2000>;
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pinctrl-names = "default";
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pinctrl-0 = <&auart0_2pins_a>;
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qca7000: ethernet {
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compatible = "qca,qca7000";
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local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
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current-speed = <38400>;
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};
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};
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