On Wed, Jun 13, 2012 at 11:50:35AM -0500, Rob Herring wrote: > On 06/13/2012 10:28 AM, Richard Zhao wrote: > > On Wed, Jun 13, 2012 at 10:09:54AM -0500, Rob Herring wrote: > >> On 06/13/2012 07:34 AM, Richard Zhao wrote: > >>> Sometimes, boards have gpios that don't own by any driver or owner > >>> by a generic driver that don't like hacks. Such gpios is normally > >>> output and need setup once on boot. So I introduce the config-on-boot > >>> gpios. > >>> > >>> Signed-off-by: Richard Zhao <richard.zhao@xxxxxxxxxxxxx> > >>> Cc: Shawn Guo <shawn.guo@xxxxxxxxxx> > >>> Cc: Rob Herring <rob.herring@xxxxxxxxxxx> > >>> Cc: Grant Likely <grant.likely@xxxxxxxxxxxx> > >>> --- > >>> .../devicetree/bindings/arm/config-on-boot.txt | 12 +++++++ > >>> arch/arm/boot/dts/imx6q-sabrelite.dts | 7 ++++ > >>> arch/arm/mach-imx/mach-imx6q.c | 35 ++++++++++++++++++++ > >>> 3 files changed, 54 insertions(+) > >>> create mode 100644 Documentation/devicetree/bindings/arm/config-on-boot.txt > >>> > >>> diff --git a/Documentation/devicetree/bindings/arm/config-on-boot.txt b/Documentation/devicetree/bindings/arm/config-on-boot.txt > >>> new file mode 100644 > >>> index 0000000..f98ed74 > >>> --- /dev/null > >>> +++ b/Documentation/devicetree/bindings/arm/config-on-boot.txt > >>> @@ -0,0 +1,12 @@ > >>> +* Configure on Boot > >>> + > >>> +Node name: config-on-boot > >>> + It must be in root node. config-on-boot means to describe settings that needs > >>> + to be set one time on boot but aren't owned by any driver, or the owned driver > >>> + is too generic to handle such settings. For example, usb hub uses generic > >>> + driver in usb core code, a on-board usb may need deassert reset pin. > >> > >> NAK. This is not a h/w description > > It's misc things, but is hw description. > > You are defining something based on whether linux has a driver or not. > That should not matter to DT. That's backwards. I just define the board needs some misc settings. If you think config-on-boot is not good, we can name it like config-misc. > > >> and should be solved within the > >> kernel or bootloader. Either fix this in u-boot, > > Kernel might be better not to depend on uboot. > >> the platform code, or > > How do I get gpio in platfrom code without dts description? > >> make the generic driver support this in a generic way. > > It's called just after populate devices. It's hard for generic driver to > > decide when it's called. > > You need to describe that you have a hub on the usb bus and add the gpio > line to that node. Just like PCI is probe-able, you still need DT nodes > sometimes for cases like this. PCI has dev id and may add quirks. But for embedded, I don't know how to connect a of node to a hub device enumerated by usb core code. And it may also pollute the usb core code. > A simpler approach would be to just add > the gpio to the ehci controller node, but that's not exactly correct. That's exactly why this patch comes out. Thanks Richard > > Rob > > > > > > Thanks > > Richard > >> > >> Rob > >> -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
