On 10:31 Sun 29 Jan     , Simon Glass wrote:

Hi,

On Fri, Jan 27, 2012 at 9:10 PM, Jean-Christophe PLAGNIOL-VILLARD
[off-list ref] wrote:

quoted

use a local copy of board informatin and fill with DT data

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <redacted>
Cc: Nicolas Ferre <redacted>
Cc: devicetree-discuss at lists.ozlabs.org
Cc: linux-mtd at lists.infradead.org
---
?.../devicetree/bindings/mtd/atmel-nand.txt ? ? ? ? | ? 41 ++++++++
?drivers/mtd/nand/atmel_nand.c ? ? ? ? ? ? ? ? ? ? ?| ?107 ++++++++++++++++----
?2 files changed, 130 insertions(+), 18 deletions(-)
?create mode 100644 Documentation/devicetree/bindings/mtd/atmel-nand.txt

diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
new file mode 100644
index 0000000..a910ab9
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt

@@ -0,0 +1,41 @@
+Atmel NAND flash
+
+Required properties:
+- compatible : "atmel,at91rm9200-nand".
+- reg : should specify localbus address and size used for the chip,
+ ? ? ? and if availlable the ECC.
+- atmel,nand-addr-offset : offset for the address latch.
+- atmel,nand-cmd-offset : offset for the command latch.
+- #address-cells, #size-cells : Must be present if the device has sub-nodes
+ ?representing partitions.
+
+- gpios : specifies the gpio pins to control the NAND device. detect is an
+ ?optional gpio and may be set to 0 if not present.

What does this mean please? What is 'detect' and what 'control' do the
gpios provide?

Below you have two GPIOs pioC 13 and pioC 14. I think the binding
should document the two GPIOs, the order, and what they are for.

no as it's said in the binding the detect pin is optional

quoted

+
+Optional properties:
+- nand-ecc-mode : String, operation mode of the NAND ecc mode, soft by default.
+ ?Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
+ ?"soft_bch".
+- nand-bus-width : 8 or 16 bus width if not present 8
+- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false
+
+Examples:
+nand0: nand at 40000000,0 {
+ ? ? ? compatible = "atmel,at91rm9200-nand";
+ ? ? ? #address-cells = <1>;
+ ? ? ? #size-cells = <1>;
+ ? ? ? reg = <0x40000000 0x10000000
+ ? ? ? ? ? ? ?0xffffe800 0x200
+ ? ? ? ? ? ? >;
+ ? ? ? atmel,nand-addr-offset = <21>;
+ ? ? ? atmel,nand-cmd-offset = <22>;
+ ? ? ? nand-on-flash-bbt = <1>;
+ ? ? ? nand-ecc-mode = "soft";
+ ? ? ? gpios = <&pioC 13 0
+ ? ? ? ? ? ? ? ?&pioC 14 0
+ ? ? ? ? ? ? ? ?0

Sorry, I haven't seen this before, perhaps it is a standard thing in
Linux. Does 0 mean end of list? Can we not just use the property's
size value for this?

0 means not used as specified in the DT

Best Regards,
J.