[v2 PATCH 2/3] Documentation: bindings: add description of PHY delays for sdhci-cadence

From: Piotr Sroka
Date: Mon Mar 06 2017 - 09:20:03 EST


Add description of new DLL PHY delays.

Signed-off-by: Piotr Sroka <piotrs@xxxxxxxxxxx>
---
Changes for v2:
- file was created in v2. It was a part of driver source file patch.
- most delays were moved from dts file
to data associated with an SoC specific compatible
- description of delays was updated to be more clearly
---
.../devicetree/bindings/mmc/sdhci-cadence.txt | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt b/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt
index c0f37cb..77c4b99 100644
--- a/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt
+++ b/Documentation/devicetree/bindings/mmc/sdhci-cadence.txt
@@ -19,6 +19,23 @@ if supported. See mmc.txt for details.
- mmc-hs400-1_8v
- mmc-hs400-1_2v

+Some PHY delays can be configured by following properties.
+Each delay property represents the fraction of the clock period.
+The approximate delay value will be
+(<delay property value>/128)*sdmclk_clock_period.
+- phy-dll-delay-sdclk:
+ Value of the delay introduced on the sdclk output
+ for all modes except HS200, HS400 and HS400_ES.
+ Valid range = [0:0x7F].
+- phy-dll-delay-sdclk-hsmmc:
+ Value of the delay introduced on the sdclk output
+ for HS200, HS400 and HS400_ES speed modes.
+ Valid range = [0:0x7F].
+- phy-dll-delay-strobe:
+ Value of the delay introduced on the dat_strobe input
+ used in HS400 / HS400_ES speed modes.
+ Valid range = [0:0x7F].
+
Example:
emmc: sdhci@5a000000 {
compatible = "socionext,uniphier-sd4hc", "cdns,sd4hc";
@@ -29,4 +46,5 @@ Example:
mmc-ddr-1_8v;
mmc-hs200-1_8v;
mmc-hs400-1_8v;
+ phy-dll-delay-sdclk = <0>;
};
--
2.2.2