On 01/08/2015 02:04 AM, Peter Pan 潘栋 (peterpandong) wrote: >>> This commit adds the devicetree binding document that specifies the >>> spi nand devices support. >>> >>> Signed-off-by: Peter Pan <peterpandong@xxxxxxxxxx> >>> --- >>> Documentation/devicetree/bindings/mtd/spi-nand.txt | 22 >> ++++++++++++++++++++++ >>> 1 file changed, 22 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/mtd/spi- >> nand.txt >>> >>> diff --git a/Documentation/devicetree/bindings/mtd/spi-nand.txt >> b/Documentation/devicetree/bindings/mtd/spi-nand.txt >>> new file mode 100644 >>> index 0000000..9dd3efd >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/mtd/spi-nand.txt >>> @@ -0,0 +1,22 @@ >>> +* NAND driver for MT29F, GD5F and similar SPI NAND flash chips >>> + >>> +Required properties: >>> +- #address-cells, #size-cells : Must be present if the device has >> sub-nodes >>> + representing partitions. >>> +- compatible : Should be the manufacturer and the name of the chip. >> Bear in mind >>> >> >> Unless I'm mistaken, we don't need the chip ID here, as SPI NAND allows >> to autodetect the device. Any reason why we can't just use a generic >> compatible "spi-nand" here? >> -- >> Ezequiel > > In fact, I don't know how to autodetect the SPI NAND device. Micron device and > Gigadevice device have different read ID functions. The Chip ID here is used to > determine which function to use. > Isn't the difference between the Read ID very minor? One of the vendor needs a 2-byte ID read, and the other one needs a 3-byte ID read. So you can just try with 2-byte, and if that fails (no vendor ID is found on the first byte), you can try with the 3-byte command. It's not the most elegant solution, but it's not super awful either. -- Ezequiel -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
