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    SubjectApplied "spi: document tx/rx clock delay properties" to the spi tree
    Date
    The patch

    spi: document tx/rx clock delay properties

    has been applied to the spi tree at

    https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git

    All being well this means that it will be integrated into the linux-next
    tree (usually sometime in the next 24 hours) and sent to Linus during
    the next merge window (or sooner if it is a bug fix), however if
    problems are discovered then the patch may be dropped or reverted.

    You may get further e-mails resulting from automated or manual testing
    and review of the tree, please engage with people reporting problems and
    send followup patches addressing any issues that are reported if needed.

    If any updates are required or you are submitting further changes they
    should be sent as incremental updates against current git, existing
    patches will not be replaced.

    Please add any relevant lists and maintainers to the CCs when replying
    to this mail.

    Thanks,
    Mark

    From 7558f978f9b66a2bc284a0e8c0764b88305bc29f Mon Sep 17 00:00:00 2001
    From: Sowjanya Komatineni <skomatineni@nvidia.com>
    Date: Thu, 4 Apr 2019 17:14:18 -0700
    Subject: [PATCH] spi: document tx/rx clock delay properties

    Tegra SPI controller has TX and RX trimmers to tuning the delay of
    SPI master clock with respect to the data.

    TX and RX tap values are based on the platform validation across the
    PVT and the trimmer values vary based on the trace lengths to the
    corresponding SPI devices.

    Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
    Signed-off-by: Mark Brown <broonie@kernel.org>
    ---
    .../bindings/spi/nvidia,tegra114-spi.txt | 20 +++++++++++++++++++
    1 file changed, 20 insertions(+)

    diff --git a/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt b/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt
    index 9ba7c5a273b4..db8e0d71c5bc 100644
    --- a/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt
    +++ b/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt
    @@ -23,6 +23,18 @@ Required properties:
    Recommended properties:
    - spi-max-frequency: Definition as per
    Documentation/devicetree/bindings/spi/spi-bus.txt
    +Optional properties:
    +- nvidia,tx-clk-tap-delay: Delays the clock going out to the external device
    + with this tap value. This property is used to tune the outgoing data from
    + Tegra SPI master with respect to outgoing Tegra SPI master clock.
    + Tap values vary based on the platform design trace lengths from Tegra SPI
    + to corresponding slave devices. Valid tap values are from 0 thru 63.
    +- nvidia,rx-clk-tap-delay: Delays the clock coming in from the external device
    + with this tap value. This property is used to adjust the Tegra SPI master
    + clock with respect to the data from the SPI slave device.
    + Tap values vary based on the platform design trace lengths from Tegra SPI
    + to corresponding slave devices. Valid tap values are from 0 thru 63.
    +
    Example:

    spi@7000d600 {
    @@ -38,4 +50,12 @@ spi@7000d600 {
    reset-names = "spi";
    dmas = <&apbdma 16>, <&apbdma 16>;
    dma-names = "rx", "tx";
    + <spi-client>@<bus_num> {
    + ...
    + ...
    + nvidia,rx-clk-tap-delay = <0>;
    + nvidia,tx-clk-tap-delay = <16>;
    + ...
    + };
    +
    };
    --
    2.20.1
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