summaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/mmc/synopsis-dw-mshc.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/devicetree/bindings/mmc/synopsis-dw-mshc.txt')
-rw-r--r--Documentation/devicetree/bindings/mmc/synopsis-dw-mshc.txt79
1 files changed, 79 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mmc/synopsis-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/synopsis-dw-mshc.txt
new file mode 100644
index 000000000000..06cd32d08052
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/synopsis-dw-mshc.txt
@@ -0,0 +1,79 @@
+* Synopsis Designware Mobile Storage Host Controller
+
+The Synopsis designware mobile storage host controller is used to interface
+a SoC with storage medium such as eMMC or SD/MMC cards. This file documents
+differences between the core mmc properties described by mmc.txt and the
+properties used by the Synopsis Designware Mobile Storage Host Controller.
+
+Required Properties:
+
+* compatible: should be
+ - snps,dw-mshc: for controllers compliant with synopsis dw-mshc.
+* #address-cells: should be 1.
+* #size-cells: should be 0.
+
+# Slots: The slot specific information are contained within child-nodes with
+ each child-node representing a supported slot. There should be atleast one
+ child node representing a card slot. The name of the child node representing
+ the slot is recommended to be slot@n where n is the unique number of the slot
+ connnected to the controller. The following are optional properties which
+ can be included in the slot child node.
+
+ * reg: specifies the physical slot number. The valid values of this
+ property is 0 to (num-slots -1), where num-slots is the value
+ specified by the num-slots property.
+
+ * bus-width: as documented in mmc core bindings.
+
+ * wp-gpios: specifies the write protect gpio line. The format of the
+ gpio specifier depends on the gpio controller. If the write-protect
+ line is not available, this property is optional.
+
+Optional properties:
+
+* num-slots: specifies the number of slots supported by the controller.
+ The number of physical slots actually used could be equal or less than the
+ value specified by num-slots. If this property is not specified, the value
+ of num-slot property is assumed to be 1.
+
+* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
+ specified, the default value of the fifo size is determined from the
+ controller registers.
+
+* card-detect-delay: Delay in milli-seconds before detecting card after card
+ insert event. The default value is 0.
+
+* supports-highspeed: Enables support for high speed cards (upto 50MHz)
+
+* broken-cd: as documented in mmc core bindings.
+
+Aliases:
+
+- All the MSHC controller nodes should be represented in the aliases node using
+ the following format 'mshc{n}' where n is a unique number for the alias.
+
+Example:
+
+The MSHC controller node can be split into two portions, SoC specific and
+board specific portions as listed below.
+
+ dwmmc0@12200000 {
+ compatible = "snps,dw-mshc";
+ reg = <0x12200000 0x1000>;
+ interrupts = <0 75 0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ dwmmc0@12200000 {
+ num-slots = <1>;
+ supports-highspeed;
+ broken-cd;
+ fifo-depth = <0x80>;
+ card-detect-delay = <200>;
+
+ slot@0 {
+ reg = <0>;
+ bus-width = <8>;
+ };
+ };