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-rw-r--r--Documentation/devicetree/bindings/mmc/mmc.txt178
1 files changed, 1 insertions, 177 deletions
diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt
index c269dbe384fe..bf9d7d3febf1 100644
--- a/Documentation/devicetree/bindings/mmc/mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc.txt
@@ -1,177 +1 @@
-These properties are common to multiple MMC host controllers. Any host
-that requires the respective functionality should implement them using
-these definitions.
-
-Interpreted by the OF core:
-- reg: Registers location and length.
-- interrupts: Interrupts used by the MMC controller.
-
-Card detection:
-If no property below is supplied, host native card detect is used.
-Only one of the properties in this section should be supplied:
- - broken-cd: There is no card detection available; polling must be used.
- - cd-gpios: Specify GPIOs for card detection, see gpio binding
- - non-removable: non-removable slot (like eMMC); assume always present.
-
-Optional properties:
-- bus-width: Number of data lines, can be <1>, <4>, or <8>. The default
- will be <1> if the property is absent.
-- wp-gpios: Specify GPIOs for write protection, see gpio binding
-- cd-inverted: when present, polarity on the CD line is inverted. See the note
- below for the case, when a GPIO is used for the CD line
-- cd-debounce-delay-ms: Set delay time before detecting card after card insert interrupt.
- It's only valid when cd-gpios is present.
-- wp-inverted: when present, polarity on the WP line is inverted. See the note
- below for the case, when a GPIO is used for the WP line
-- disable-wp: When set no physical WP line is present. This property should
- only be specified when the controller has a dedicated write-protect
- detection logic. If a GPIO is always used for the write-protect detection
- logic it is sufficient to not specify wp-gpios property in the absence of a WP
- line.
-- max-frequency: maximum operating clock frequency
-- no-1-8-v: when present, denotes that 1.8v card voltage is not supported on
- this system, even if the controller claims it is.
-- cap-sd-highspeed: SD high-speed timing is supported
-- cap-mmc-highspeed: MMC high-speed timing is supported
-- sd-uhs-sdr12: SD UHS SDR12 speed is supported
-- sd-uhs-sdr25: SD UHS SDR25 speed is supported
-- sd-uhs-sdr50: SD UHS SDR50 speed is supported
-- sd-uhs-sdr104: SD UHS SDR104 speed is supported
-- sd-uhs-ddr50: SD UHS DDR50 speed is supported
-- cap-power-off-card: powering off the card is safe
-- cap-mmc-hw-reset: eMMC hardware reset is supported
-- cap-sdio-irq: enable SDIO IRQ signalling on this interface
-- full-pwr-cycle: full power cycle of the card is supported
-- mmc-ddr-3_3v: eMMC high-speed DDR mode(3.3V I/O) is supported
-- mmc-ddr-1_8v: eMMC high-speed DDR mode(1.8V I/O) is supported
-- mmc-ddr-1_2v: eMMC high-speed DDR mode(1.2V I/O) is supported
-- mmc-hs200-1_8v: eMMC HS200 mode(1.8V I/O) is supported
-- mmc-hs200-1_2v: eMMC HS200 mode(1.2V I/O) is supported
-- mmc-hs400-1_8v: eMMC HS400 mode(1.8V I/O) is supported
-- mmc-hs400-1_2v: eMMC HS400 mode(1.2V I/O) is supported
-- mmc-hs400-enhanced-strobe: eMMC HS400 enhanced strobe mode is supported
-- dsr: Value the card's (optional) Driver Stage Register (DSR) should be
- programmed with. Valid range: [0 .. 0xffff].
-- no-sdio: controller is limited to send sdio cmd during initialization
-- no-sd: controller is limited to send sd cmd during initialization
-- no-mmc: controller is limited to send mmc cmd during initialization
-- fixed-emmc-driver-type: for non-removable eMMC, enforce this driver type.
- The value <n> is the driver type as specified in the eMMC specification
- (table 206 in spec version 5.1).
-- post-power-on-delay-ms : It was invented for MMC pwrseq-simple which could
- be referred to mmc-pwrseq-simple.txt. But now it's reused as a tunable delay
- waiting for I/O signalling and card power supply to be stable, regardless of
- whether pwrseq-simple is used. Default to 10ms if no available.
-- supports-cqe : The presence of this property indicates that the corresponding
- MMC host controller supports HW command queue feature.
-- disable-cqe-dcmd: This property indicates that the MMC controller's command
- queue engine (CQE) does not support direct commands (DCMDs).
-
-*NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line
-polarity properties, we have to fix the meaning of the "normal" and "inverted"
-line levels. We choose to follow the SDHCI standard, which specifies both those
-lines as "active low." Therefore, using the "cd-inverted" property means, that
-the CD line is active high, i.e. it is high, when a card is inserted. Similar
-logic applies to the "wp-inverted" property.
-
-CD and WP lines can be implemented on the hardware in one of two ways: as GPIOs,
-specified in cd-gpios and wp-gpios properties, or as dedicated pins. Polarity of
-dedicated pins can be specified, using *-inverted properties. GPIO polarity can
-also be specified using the GPIO_ACTIVE_LOW flag. This creates an ambiguity
-in the latter case. We choose to use the XOR logic for GPIO CD and WP lines.
-This means, the two properties are "superimposed," for example leaving the
-GPIO_ACTIVE_LOW flag clear and specifying the respective *-inverted property
-property results in a double-inversion and actually means the "normal" line
-polarity is in effect.
-
-Optional SDIO properties:
-- keep-power-in-suspend: Preserves card power during a suspend/resume cycle
-- wakeup-source: Enables wake up of host system on SDIO IRQ assertion
- (Legacy property supported: "enable-sdio-wakeup")
-
-MMC power
----------
-
-Controllers may implement power control from both the connected cards and
-the IO signaling (for example to change to high-speed 1.8V signalling). If
-the system supports this, then the following two properties should point
-to valid regulator nodes:
-
-- vqmmc-supply: supply node for IO line power
-- vmmc-supply: supply node for card's power
-
-
-MMC power sequences:
---------------------
-
-System on chip designs may specify a specific MMC power sequence. To
-successfully detect an (e)MMC/SD/SDIO card, that power sequence must be
-maintained while initializing the card.
-
-Optional property:
-- mmc-pwrseq: phandle to the MMC power sequence node. See "mmc-pwrseq-*"
- for documentation of MMC power sequence bindings.
-
-
-Use of Function subnodes
-------------------------
-
-On embedded systems the cards connected to a host may need additional
-properties. These can be specified in subnodes to the host controller node.
-The subnodes are identified by the standard 'reg' property.
-Which information exactly can be specified depends on the bindings for the
-SDIO function driver for the subnode, as specified by the compatible string.
-
-Required host node properties when using function subnodes:
-- #address-cells: should be one. The cell is the slot id.
-- #size-cells: should be zero.
-
-Required function subnode properties:
-- reg: Must contain the SDIO function number of the function this subnode
- describes. A value of 0 denotes the memory SD function, values from
- 1 to 7 denote the SDIO functions.
-
-Optional function subnode properties:
-- compatible: name of SDIO function following generic names recommended practice
-
-
-Examples
---------
-
-Basic example:
-
-sdhci@ab000000 {
- compatible = "sdhci";
- reg = <0xab000000 0x200>;
- interrupts = <23>;
- bus-width = <4>;
- cd-gpios = <&gpio 69 0>;
- cd-inverted;
- wp-gpios = <&gpio 70 0>;
- max-frequency = <50000000>;
- keep-power-in-suspend;
- wakeup-source;
- mmc-pwrseq = <&sdhci0_pwrseq>
-}
-
-Example with sdio function subnode:
-
-mmc3: mmc@1c12000 {
- #address-cells = <1>;
- #size-cells = <0>;
-
- pinctrl-names = "default";
- pinctrl-0 = <&mmc3_pins_a>;
- vmmc-supply = <&reg_vmmc3>;
- bus-width = <4>;
- non-removable;
- mmc-pwrseq = <&sdhci0_pwrseq>
-
- brcmf: bcrmf@1 {
- reg = <1>;
- compatible = "brcm,bcm43xx-fmac";
- interrupt-parent = <&pio>;
- interrupts = <10 8>; /* PH10 / EINT10 */
- interrupt-names = "host-wake";
- };
-};
+This file has moved to mmc-controller.yaml.