linux_dsm_epyc7002/Documentation/devicetree/bindings/mmc/sdhci-atmel.txt
Nicolas Ferre 5cd41fe897 dt-bindings: sdhci-of-at91: add the microchip,sdcal-inverted property
Add the specific microchip,sdcal-inverted property to at91 sdhci
device binding.
This optional property describes how the SoC SDCAL pin is connected.
It could be handled at SiP, SoM or board level.

This property read by at91 sdhci driver will allow to put in place a
software workaround that would reduce power consumption.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-11-13 16:10:16 +01:00

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* Atmel SDHCI controller
This file documents the differences between the core properties in
Documentation/devicetree/bindings/mmc/mmc.txt and the properties used by the
sdhci-of-at91 driver.
Required properties:
- compatible: Must be "atmel,sama5d2-sdhci".
- clocks: Phandlers to the clocks.
- clock-names: Must be "hclock", "multclk", "baseclk";
Optional properties:
- microchip,sdcal-inverted: when present, polarity on the SDCAL SoC pin is
inverted. The default polarity for this signal is described in the datasheet.
For instance on SAMA5D2, the pin is usually tied to the GND with a resistor
and a capacitor (see "SDMMC I/O Calibration" chapter).
Example:
sdmmc0: sdio-host@a0000000 {
compatible = "atmel,sama5d2-sdhci";
reg = <0xa0000000 0x300>;
interrupts = <31 IRQ_TYPE_LEVEL_HIGH 0>;
clocks = <&sdmmc0_hclk>, <&sdmmc0_gclk>, <&main>;
clock-names = "hclock", "multclk", "baseclk";
};