On Wed, May 15, 2013 at 12:51:12PM +0530, Sujit Reddy Thumma wrote:

On 5/14/2013 11:38 PM, Olof Johansson wrote:

quoted

On Tue, May 14, 2013 at 12:08 AM, Dolev Raviv [off-list ref] wrote:

quoted

Compatible list is used in commit 03b1781 but is not documented.
Add necessary device tree bindings to describe on-chip UFS host
controllers.

Signed-off-by: Sujit Reddy Thumma <redacted>

diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
new file mode 100644
index 0000000..20468b2
--- /dev/null
+++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt

@@ -0,0 +1,16 @@
+* Universal Flash Storage (UFS) Host Controller
+
+UFSHC nodes are defined to describe on-chip UFS host controllers.
+Each UFS controller instance should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "jedec,ufs-1.1"
+- interrupts        : <interrupt mapping for UFS host controller IRQ>
+- reg               : <registers mapping>
+
+Example:
+       ufshc@0xfc598000 {
+               compatible = "jedec,ufs-1.1";

Hmm.

Does jedec really specify the programming interface of this type of
device, register layout and meaning? It seems to be more about the
command set and electrical/connectivity specifications, no?

That's true with UFS device specification. For UFS Host Controller
specification Jedec indeed standardized the hardware registers,
memory structures and register programming sequence to talk to UFS
device.

Ok, fair enough. However, I think "jedec,ufshc-1.1" would be more
appropriate to avoid ambiguities. Compare to SD where "sdhci" is the
only compatible string used for the standard interface.


-Olof