On Fri, Jan 08, 2016 at 08:32:45AM -0600, Rob Herring wrote: > On Thu, Jan 7, 2016 at 11:44 PM, Peter Chen <peter.chen@xxxxxxxxxxxxx> wrote: > > Although most of USB devices are hot-plug's, there are still some devices > > are hard wired on the board, eg, for HSIC and SSIC interface USB devices. > > If these kinds of USB devices are multiple functions, and they can supply > > other interfaces like i2c, gpios for other devices, we may need to > > descirbe these at device tree. > > > > In this commit, it uses "reg" in dts as port number to match the port > > number decided by USB core, if they are the same, then the device node > > is for the device we are creating for USB core. > > > > Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx> > > --- > > .../devicetree/bindings/usb/usb-device.txt | 8 ++++ > > drivers/usb/core/Makefile | 2 +- > > drivers/usb/core/of.c | 48 ++++++++++++++++++++++ > > drivers/usb/core/usb.c | 8 +++- > > include/linux/usb.h | 2 + > > include/linux/usb/of.h | 6 +++ > > 6 files changed, 71 insertions(+), 3 deletions(-) > > create mode 100644 Documentation/devicetree/bindings/usb/usb-device.txt > > create mode 100644 drivers/usb/core/of.c > > > > diff --git a/Documentation/devicetree/bindings/usb/usb-device.txt b/Documentation/devicetree/bindings/usb/usb-device.txt > > new file mode 100644 > > index 0000000..d35facd > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/usb/usb-device.txt > > @@ -0,0 +1,8 @@ > > +Generic USB Device Properties > > + > > +Usually, we only use device tree for hard wired USB device. > > +The reference binding doc is from: > > +http://playground.sun.com/1275/bindings/usb/usb-1_0.ps. > > This path doesn't exist anymore. Use > http://www.firmware.org/1275/bindings/usb/usb-1_0.ps > Ok. > > + > > +Required properties: > > +- reg: the port number which this device is connecting to. > > At least compatible should also be here. > What format for USB device compatible string has still not been decided. Would you suggest something? At my example, I use "vid,pid". > > + */ > > +struct device_node *usb_of_find_node(struct device_node *parent, int portnum) > > +{ > > + struct device_node *node; > > + u32 port; > > + > > + for_each_child_of_node(parent, node) { > > + if (!of_property_read_u32(node, "reg", &port)) { > > + if (port == portnum) > > + return node; > > This needs to match on the compatible string too. Otherwise, this > could match in lots of cases. > No, the port number is unique under the USB HUB (including host controller, which is roothub), and there are some many compatible string for USB devices. -- Best Regards, Peter Chen -- 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
