On Wed, 5 Dec 2012 16:33:48 -0600, Jon Hunter <jon-hunter@xxxxxx> wrote: > Hi Grant, > > On 12/05/2012 04:22 PM, Grant Likely wrote: > > On Wed, 5 Dec 2012 20:09:31 +0100, Daniel Mack <zonque@xxxxxxxxx> wrote: > >> This patch adds basic DT bindings for OMAP GPMC. > >> > >> The actual peripherals are instantiated from child nodes within the GPMC > >> node, and the only type of device that is currently supported is NAND. > >> > >> Code was added to parse the generic GPMC timing parameters and some > >> documentation with examples on how to use them. > >> > >> Successfully tested on an AM33xx board. > >> > >> Signed-off-by: Daniel Mack <zonque@xxxxxxxxx> > >> --- > >> Documentation/devicetree/bindings/bus/ti-gpmc.txt | 77 ++++++++++ > >> .../devicetree/bindings/mtd/gpmc-nand.txt | 76 +++++++++ > >> arch/arm/mach-omap2/gpmc.c | 171 ++++++++++++++++++++- > >> 3 files changed, 323 insertions(+), 1 deletion(-) > >> create mode 100644 Documentation/devicetree/bindings/bus/ti-gpmc.txt > >> create mode 100644 Documentation/devicetree/bindings/mtd/gpmc-nand.txt > >> > >> diff --git a/Documentation/devicetree/bindings/bus/ti-gpmc.txt b/Documentation/devicetree/bindings/bus/ti-gpmc.txt > >> new file mode 100644 > >> index 0000000..7d2a645 > >> --- /dev/null > >> +++ b/Documentation/devicetree/bindings/bus/ti-gpmc.txt > >> @@ -0,0 +1,77 @@ > >> +Device tree bindings for OMAP general purpose memory controllers (GPMC) > >> + > >> +The actual devices are instantiated from the child nodes of a GPMC node. > >> + > >> +Required properties: > >> + > >> + - compatible: Should be set to "ti,gpmc" > > > > Please, be specific. Use something like "ti,am3340-gpmc" or > > "ti,omap3430-gpmc". The compatible property is a list so that new > > devices can claim compatibility with old. Compatible strings that are > > overly generic are a pet-peave of mine. > > We aim to use the binding for omap2,3,4,5 as well as the am33xx devices > (which are omap based). Would it be sufficient to have "ti,omap2-gpmc" > implying all omap2+ based devices or should we have a compatible string > for each device supported? Are they each register-level compatible with one another? The general recommended approach here is to make subsequent silicon claim compatibility with the first compatible implementation. So, for an am3358 board: compatible = "ti,am3358-gpmc", "ti,omap2420-gpmc"; Essentially, what this means is that "ti,omap2420-gpmc" is the generic value instead of "omap2-gpmc". The reason for this is so that the value is anchored against a specific implementation, and not against something completely imaginary or idealized. If a newer version isn't quite compatible with the omap2420-gpmc, then it can drop the compatible claim and the driver really should be told about the new device. g. > > Thanks > Jon > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Grant Likely, B.Sc, P.Eng. Secret Lab Technologies, Ltd. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
