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SubjectRe: [PATCH V1 21/26] DT bindings: spi: add tx/rx clock delay SPI client properties
On Tue, Mar 26, 2019 at 10:56:42PM -0700, Sowjanya Komatineni wrote:
> This patch adds Tegra SPI master tx and rx clock delay properties.
>
> TX/RX clock delays may vary depending on the platform design trace lengths
> for each client on the Tegra SPI bus. These properties helps to tune the
> clock delays.
>
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
> .../devicetree/bindings/spi/nvidia,tegra114-spi.txt | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)

Just combine this with patch 19.

> diff --git a/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt b/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt
> index 6167c5234b64..2b84b7b726ce 100644
> --- a/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt
> +++ b/Documentation/devicetree/bindings/spi/nvidia,tegra114-spi.txt
> @@ -29,6 +29,12 @@ spi-client device controller properties:
> - nvidia,cs-hold-clk-count: CS hold timing parameter.
> - nvidia,cs-inactive-cycles: CS inactive delay in terms of clock between
> transfers.
> +- 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.
> +- 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.

Are there units? What's the range of values.

>
> Example:
>
> @@ -45,4 +51,14 @@ spi@7000d600 {
> reset-names = "spi";
> dmas = <&apbdma 16>, <&apbdma 16>;
> dma-names = "rx", "tx";
> +
> + <spi-client>@<bus_num> {
> + ...
> + ...
> + nvidia,cs-setup-clk-count = <10>;
> + nvidia,cs-hold-clk-count = <10>;
> + nvidia,rx-clk-tap-delay = <0>;
> + nvidia,tx-clk-tap-delay = <16>;
> + ...
> + };
> };
> --
> 2.7.4
>


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