How the set the VID and PID of a USB device in Embedded Linux

I have a an Embedded Linux device and I would like to set the VID, PID and name. Where is this normally done? In 开发者_JAVA百科the file system or is the compiled into the kernel?

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It is done in the kernel: I presume that you have a USB gadget driver that you have developped or that you are using so that your Embedded Linux device can be used as a USB device.

This driver certainly has a struct usb_device_descriptor that is declared somewhere. As you can see, this struct has some idVendor, idProduct fields. The human readable strings are iManufacturer, iProduct and iSerialNum. Here is the complete struct:

/* USB_DT_DEVICE: Device descriptor */
struct usb_device_descriptor {
    __u8  bLength;
    __u8  bDescriptorType;

    __le16 bcdUSB;
    __u8  bDeviceClass;
    __u8  bDeviceSubClass;
    __u8  bDeviceProtocol;
    __u8  bMaxPacketSize0;
    __le16 idVendor;
    __le16 idProduct;
    __le16 bcdDevice;
    __u8  iManufacturer;
    __u8  iProduct;
    __u8  iSerialNumber;
    __u8  bNumConfigurations;
} __attribute__ ((packed));

If you are using an already developped driver, some give you the possibility to set these fields with some values that you pass as module parameter, see drivers/usb/gadget/printer.c for a very good example. This way, you could pass the values to the kernel, from userspace.