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Diffstat (limited to 'Documentation/devicetree/bindings/mmc/mmc.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/mmc/mmc.txt | 178 |
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 = <®_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. |