mtd: nand: davinci: extend description of bindings

Extend bindings for davinci_nand driver to be more clear.
This is clarification only, without semantic changes.

Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Taras Kondratiuk <taras@ti.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

1 files changed, 54 insertions, 23 deletions

diff --git a/Documentation/devicetree/bindings/mtd/davinci-nand.txt b/Documentation/devicetree/bindings/mtd/davinci-nand.txt
index 3545ea704b50..d2a3fc020023 100644
--- a/Documentation/devicetree/bindings/mtd/davinci-nand.txt
+++ b/Documentation/devicetree/bindings/mtd/davinci-nand.txt
@@ -1,36 +1,67 @@
-* Texas Instruments Davinci NAND
+Device tree bindings for Texas instruments Davinci NAND controller
 
-This file provides information, what the device node for the
-davinci nand interface contain.
+This file provides information, what the device node for the davinci NAND
+interface contains.
+
+Documentation:
+Davinci DM646x - http://www.ti.com/lit/ug/sprueq7c/sprueq7c.pdf
 
 Required properties:
-- compatible: "ti,davinci-nand";
-- reg : contain 2 offset/length values:
-        - offset and length for the access window
-        - offset and length for accessing the aemif control registers
-- ti,davinci-chipselect: Indicates on the davinci_nand driver which
-                         chipselect is used for accessing the nand.
+
+- compatible:                   "ti,davinci-nand"
+
+- reg:                          Contains 2 offset/length values:
+                                - offset and length for the access window.
+                                - offset and length for accessing the AEMIF
+                                control registers.
+
+- ti,davinci-chipselect:        number of chipselect. Indicates on the
+                                davinci_nand driver which chipselect is used
+                                for accessing the nand.
+                                Can be in the range [0-3].
 
 Recommended properties :
-- ti,davinci-mask-ale: mask for ale
-- ti,davinci-mask-cle: mask for cle
-- ti,davinci-mask-chipsel: mask for chipselect
-- ti,davinci-ecc-mode: ECC mode valid values for davinci driver:
-                - "none"
-                - "soft"
-                - "hw"
-- ti,davinci-ecc-bits: used ECC bits, currently supported 1 or 4.
-- ti,davinci-nand-buswidth: buswidth 8 or 16
-- ti,davinci-nand-use-bbt: use flash based bad block table support.
-
-nand device bindings may contain additional sub-nodes describing
-partitions of the address space. See partition.txt for more detail.
+
+- ti,davinci-mask-ale:          mask for ALE. Needed for executing address
+                                phase. These offset will be added to the base
+                                address for the chip select space the NAND Flash
+                                device is connected to.
+                                If not set equal to 0x08.
+
+- ti,davinci-mask-cle:          mask for CLE. Needed for executing command
+                                phase. These offset will be added to the base
+                                address for the chip select space the NAND Flash
+                                device is connected to.
+                                If not set equal to 0x10.
+
+- ti,davinci-mask-chipsel:      mask for chipselect address. Needed to mask
+                                addresses for given chipselect.
+
+- ti,davinci-ecc-mode:          operation mode of the NAND ecc mode. ECC mode
+                                valid values for davinci driver:
+                                - "none"
+                                - "soft"
+                                - "hw"
+
+- ti,davinci-ecc-bits:          used ECC bits, currently supported 1 or 4.
+
+- ti,davinci-nand-buswidth:     buswidth 8 or 16.
+
+- ti,davinci-nand-use-bbt:      use flash based bad block table support. OOB
+                                identifier is saved in OOB area.
+
+Nand device bindings may contain additional sub-nodes describing partitions of
+the address space. See partition.txt for more detail. The NAND Flash timing
+values must be programmed in the chip select’s node of AEMIF
+memory-controller (see Documentation/devicetree/bindings/memory-controllers/
+davinci-aemif.txt).
 
 Example(da850 EVM ):
+
 nand_cs3@62000000 {
         compatible = "ti,davinci-nand";
         reg = <0x62000000 0x807ff
-                0x68000000 0x8000>;
+               0x68000000 0x8000>;
         ti,davinci-chipselect = <1>;
         ti,davinci-mask-ale = <0>;
         ti,davinci-mask-cle = <0>;