On Sat, Jan 9, 2016 at 3:05 AM, Peter Chen <hzpeterchen@xxxxxxxxx> wrote: > 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". Yes, it is. They are defined in OpenFirmware USB binding doc above. However, the compatible strings and nodes are supposed to reflect the USB descriptors and interfaces. I don't think we need that much detail here, so I'd suggest we limit it to a subset such as: usbVID.PID.REV usbVID.PID usbVID.classDC usb.classDC usbifVID.classIC usbif.classIC >> > +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. Assuming the parent node pointer is correct. You could pass a SPI host node to this function and it will return a valid device node pointer. 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
