[U-Boot] [RFC PATCH 18/20] dt-bindings: Add bindings for SPI NAND devices

[Miquel Raynal]

From: Boris Brezillon <boris.brezillon at bootlin.com>

Add bindings for SPI NAND chips.

Signed-off-by: Boris Brezillon <boris.brezillon at bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
---
 doc/device-tree-bindings/mtd/spi-nand.txt | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 doc/device-tree-bindings/mtd/spi-nand.txt

diff --git a/doc/device-tree-bindings/mtd/spi-nand.txt b/doc/device-tree-bindings/mtd/spi-nand.txt
new file mode 100644
index 0000000000..d55f80196c
--- /dev/null
+++ b/doc/device-tree-bindings/mtd/spi-nand.txt
@@ -0,0 +1,27 @@
+SPI NAND flash
+
+Required properties:
+- compatible: should be "spi-nand"
+- reg: should encode the chip-select line used to access the NAND chip
+
+Optional properties
+- spi-max-frequency: maximum frequency of the SPI bus the chip can operate at.
+		     This should encode board limitations (i.e. max freq can't
+		     be achieved due to crosstalk on IO lines).
+		     When unspecified, the driver assumes the chip can run at
+		     the max frequency defined in the spec (information
+		     extracted chip detection time).
+- spi-tx-bus-width: The bus width (number of data wires) that is used for MOSI.
+		    Only encodes the board constraints (i.e. when not all IO
+		    signals are routed on the board). Device constraints are
+		    extracted when detecting the chip, and controller
+		    constraints are exposed by the SPI mem controller. If this
+		    property is missing that means no constraint at the board
+		    level.
+- spi-rx-bus-width: The bus width (number of data wires) that is used for MISO.
+		    Only encodes the board constraints (i.e. when not all IO
+		    signals are routed on the board). Device constraints are
+		    extracted when detecting the chip, and controller
+		    constraints are exposed by the SPI mem controller. If this
+		    property is missing that means no constraint at the board
+		    level.
-- 
2.14.1