[PATCH V8 1/2] mtd: spi-nor: Bindings for Cadence Quad SPI Flash Controller driver.

Marek Vasut
2016-01-11T04:34:45Z

From: Graham Moore <grmoore-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>

Add binding document for the Cadence QSPI controller.

Signed-off-by: Graham Moore <grmoore-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>
Signed-off-by: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
Cc: Alan Tull <atull-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>
Cc: Brian Norris <computersforpeace-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: David Woodhouse <dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Cc: Dinh Nguyen <dinguyen-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>
Cc: Graham Moore <grmoore-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>
Cc: "R, Vignesh" <vigneshr-l0cyMroinI0@public.gmane.org>
Cc: Yves Vandervennet <yvanderv-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
---
.../devicetree/bindings/mtd/cadence-quadspi.txt | 56 ++++++++++++++++++++++
1 file changed, 56 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mtd/cadence-quadspi.txt

V2: Add cdns prefix to driver-specific bindings.
V3: Use existing property "is-decoded-cs" instead of creating a
duplicate, "ext-decoder". Timing parameters are in nanoseconds,
not master reference clocks. Remove bus-num completely.
V4: Add new properties fifo-width and trigger-address
V7: - Prefix all of the Cadence-specific properties with cdns prefix,
those are in particular "cdns,is-decoded-cs", "cdns,fifo-depth",
"cdns,fifo-width", "cdns,trigger-address".
- Drop bogus properties which were not used and were incorrect.
V8: Align lines to 80 chars.

diff --git a/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt b/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt
new file mode 100644
index 0000000..f248056
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt
@@ -0,0 +1,56 @@
+* Cadence Quad SPI controller
+
+Required properties:
+- compatible : Should be "cdns,qspi-nor".
+- reg : Contains two entries, each of which is a tuple consisting of a
+ physical address and length. The first entry is the address and
+ length of the controller register set. The second entry is the
+ address and length of the QSPI Controller data area.
+- interrupts : Unit interrupt specifier for the controller interrupt.
+- clocks : phandle to the Quad SPI clock.
+- cdns,fifo-depth : Size of the data FIFO in words.
+- cdns,fifo-width : Bus width of the data FIFO in bytes.
+- cdns,trigger-address : 32-bit indirect AHB trigger address.
+
+Optional properties:
+- cdns,is-decoded-cs : Flag to indicate whether decoder is used or not.
+
+Optional subnodes:
+Subnodes of the Cadence Quad SPI controller are spi slave nodes with additional
+custom properties:
+- cdns,read-delay : Delay for read capture logic, in clock cycles
+- cdns,tshsl-ns : Delay in nanoseconds for the length that the master
+ mode chip select outputs are de-asserted between
+ transactions.
+- cdns,tsd2d-ns : Delay in nanoseconds between one chip select being
+ de-activated and the activation of another.
+- cdns,tchsh-ns : Delay in nanoseconds between last bit of current
+ transaction and deasserting the device chip select
+ (qspi_n_ss_out).
+- cdns,tslch-ns : Delay in nanoseconds between setting qspi_n_ss_out low
+ and first bit transfer.
+
+Example:
+
+ qspi: spi@ff705000 {
+ compatible = "cdns,qspi-nor";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0xff705000 0x1000>,
+ <0xffa00000 0x1000>;
+ interrupts = <0 151 4>;
+ clocks = <&qspi_clk>;
+ cdns,is-decoded-cs;
+ cdns,fifo-depth = <128>;
+ cdns,fifo-width = <4>;
+ cdns,trigger-address = <0x00000000>;
+
+ flash0: n25q00@0 {
+ ...
+ cdns,read-delay = <4>;
+ cdns,tshsl-ns = <50>;
+ cdns,tsd2d-ns = <50>;
+ cdns,tchsh-ns = <4>;
+ cdns,tslch-ns = <4>;
+ };
+ };
--
2.1.4