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authorTrond Myklebust <trond.myklebust@primarydata.com>2015-02-18 07:28:37 -0800
committerTrond Myklebust <trond.myklebust@primarydata.com>2015-02-18 07:28:37 -0800
commit65d2918e716afb89359cfa59734d76c1ff8700cb (patch)
tree4685404f96642243d62c3a1a823340913d087090 /Documentation/devicetree/bindings/mmc/mmc.txt
parentbf40e5561fd288a505d5d8d8bf45eef96fe7253d (diff)
parent338d00cfef07d74a072f96821c64b20f98517d72 (diff)
downloadlwn-65d2918e716afb89359cfa59734d76c1ff8700cb.tar.gz
lwn-65d2918e716afb89359cfa59734d76c1ff8700cb.zip
Merge branch 'cleanups'
Merge cleanups requested by Linus. * cleanups: (3 commits) pnfs: Refactor the *_layout_mark_request_commit to use pnfs_layout_mark_request_commit nfs: Can call nfs_clear_page_commit() instead nfs: Provide and use helper functions for marking a page as unstable
Diffstat (limited to 'Documentation/devicetree/bindings/mmc/mmc.txt')
-rw-r--r--Documentation/devicetree/bindings/mmc/mmc.txt62
1 files changed, 61 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt
index b52628b18a53..438899e8829b 100644
--- a/Documentation/devicetree/bindings/mmc/mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc.txt
@@ -64,7 +64,43 @@ Optional SDIO properties:
- keep-power-in-suspend: Preserves card power during a suspend/resume cycle
- enable-sdio-wakeup: Enables wake up of host system on SDIO IRQ assertion
-Example:
+
+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:
+- compatible: name of SDIO function following generic names recommended practice
+- 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.
+
+
+Examples
+--------
+
+Basic example:
sdhci@ab000000 {
compatible = "sdhci";
@@ -77,4 +113,28 @@ sdhci@ab000000 {
max-frequency = <50000000>;
keep-power-in-suspend;
enable-sdio-wakeup;
+ mmc-pwrseq = <&sdhci0_pwrseq>
}
+
+Example with sdio function subnode:
+
+mmc3: mmc@01c12000 {
+ #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>
+ status = "okay";
+
+ brcmf: bcrmf@1 {
+ reg = <1>;
+ compatible = "brcm,bcm43xx-fmac";
+ interrupt-parent = <&pio>;
+ interrupts = <10 8>; /* PH10 / EINT10 */
+ interrupt-names = "host-wake";
+ };
+};