[Buildroot] gadget uevents not detected by udevmonitor

[Buildroot] gadget uevents not detected by udevmonitor

[Christopher Taylor]

I'e configured hotplug and netlink sockets in my kernel 2.6.24 config file
and I've insmoded g_serial.  When I run udevmonitor I'm not seeing uevents
when I plug in the usb cable to the usb device port.  I am however getting
the gadget serial messages:
gs_disconnect: Gadget Serial disconnected
gs_setup_complete: status error, status=0, actual-16, length=18
gs_disconnect: Gadget Serial disconnected
gs_set_config: gadget Serial configured, full speec CDC-ACM config

I'm 100% sure this is an error on my part when building everything, but I'm
not sure where.

My whole intent here is to get uevents into my application via a netlink
socket.  I have no intent of running udev, but I do intent on listening on
that the netlink socket just like udev does so I can tell immediately when a
usb event occurs.

Any advice would be appreciated.

-Chris
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[Buildroot] gadget uevents not detected by udevmonitor

[Hamish Moffatt]

On Sat, Sep 13, 2008 at 09:33:32PM -0400, Christopher Taylor wrote:
> I'e configured hotplug and netlink sockets in my kernel 2.6.24 config file
> and I've insmoded g_serial.  When I run udevmonitor I'm not seeing uevents
> when I plug in the usb cable to the usb device port.  I am however getting
> the gadget serial messages:
> gs_disconnect: Gadget Serial disconnected
> gs_setup_complete: status error, status=0, actual-16, length=18
> gs_disconnect: Gadget Serial disconnected
> gs_set_config: gadget Serial configured, full speec CDC-ACM config
> 
> I'm 100% sure this is an error on my part when building everything, but I'm
> not sure where.
> 
> My whole intent here is to get uevents into my application via a netlink
> socket.  I have no intent of running udev, but I do intent on listening on
> that the netlink socket just like udev does so I can tell immediately when a
> usb event occurs.

Are you sure that the kernel even generates such events? My experience
with the gadget subsystem is that it doesn't really integrate much with
the rest of the system.

I don't think buildroot can influence this.

Hamish
-- 
Hamish Moffatt VK3SB <hamish@debian.org> <hamish@cloud.net.au>

[Buildroot] gadget uevents not detected by udevmonitor

[Christopher Taylor]

> Are you sure that the kernel even generates such events? My experience
> with the gadget subsystem is that it doesn't really integrate much with
> the rest of the system.
>
> I don't think buildroot can influence this.


After talking crawling through udc and gadget driver code, and more
importabtly talking with the USB maintainters, it turns out you are
correct; the gadget system does not immit uevents.

I'm talking with them now on the linux-usb list to see what it would
take to implement such a thing.  The problem is that it looks like
it'll be specific to the udc driver and whether the platform supports
vbus detections.  At least that's my current line of thinking.  We'll
see where we go with it as the maintainers chime in with their
suggestions.

-Chris