Re: [PATCH 1/3] dt-bindings: mmc: sdhci-am654: Update Output tap delay binding
From: Rob Herring
Date: Tue Jan 14 2020 - 20:50:42 EST
On Wed, Jan 08, 2020 at 08:39:18PM +0530, Faiz Abbas wrote:
> According to latest AM65x Data Manual[1], a different output tap delay
> value is recommended for all speed modes. Therefore, replace the
> ti,otap-del-sel binding with one ti,otap-del-sel- for each MMC/SD speed
> mode.
>
> [1] http://www.ti.com/lit/gpn/am6526
>
> Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx>
> ---
> .../devicetree/bindings/mmc/sdhci-am654.txt | 21 +++++++++++++++++--
> 1 file changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/sdhci-am654.txt b/Documentation/devicetree/bindings/mmc/sdhci-am654.txt
> index 50e87df47971..c6ccecb9ae5a 100644
> --- a/Documentation/devicetree/bindings/mmc/sdhci-am654.txt
> +++ b/Documentation/devicetree/bindings/mmc/sdhci-am654.txt
> @@ -18,7 +18,20 @@ Required Properties:
> - clocks: Handles to the clock inputs.
> - clock-names: Tuple including "clk_xin" and "clk_ahb"
> - interrupts: Interrupt specifiers
> - - ti,otap-del-sel: Output Tap Delay select
> + Output tap delay for each speed mode:
> + - ti,otap-del-sel-legacy
> + - ti,otap-del-sel-mmc-hs
> + - ti,otap-del-sel-sd-hs
> + - ti,otap-del-sel-sdr12
> + - ti,otap-del-sel-sdr25
> + - ti,otap-del-sel-sdr50
> + - ti,otap-del-sel-sdr104
> + - ti,otap-del-sel-ddr50
> + - ti,otap-del-sel-ddr52
> + - ti,otap-del-sel-hs200
> + - ti,otap-del-sel-hs400
> + These bindings must be provided otherwise the driver will disable the
> + corresponding speed mode (i.e. all nodes must provide at least -legacy)
Why not just extend the existing property to be an array. We already
have properties to enable/disable speed modes.
>
> Optional Properties (Required for ti,am654-sdhci-5.1 and ti,j721e-sdhci-8bit):
> - ti,trm-icp: DLL trim select
> @@ -38,6 +51,10 @@ Example:
> interrupts = <GIC_SPI 136 IRQ_TYPE_LEVEL_HIGH>;
> sdhci-caps-mask = <0x80000007 0x0>;
> mmc-ddr-1_8v;
> - ti,otap-del-sel = <0x2>;
> + ti,otap-del-sel-legacy = <0x0>;
> + ti,otap-del-sel-mmc-hs = <0x0>;
> + ti,otap-del-sel-ddr52 = <0x5>;
> + ti,otap-del-sel-hs200 = <0x5>;
> + ti,otap-del-sel-hs400 = <0x0>;
> ti,trm-icp = <0x8>;
> };
> --
> 2.19.2
>