Re: RFC: Platform data for onboard USB assets

Andy Green
2011-03-12T23:02:39Z

On 03/12/2011 04:00 PM, Somebody in the thread at some point said:

Hi -

> This depends on the platform. On PCs, USB host controllers are usually
> PCI devices. The only way to identify them is by the PCI device name.
> Although these names don't change often, they _can_ change. On an
> embedded system there usually are only a couple of host controllers and
> they have more or less fixed names.

Right, on embedded boards typically the board definition file is
responsible for calling platform_add_device() to instantiate the usb
host / gadget / otg controllers. That is done deterministically each
boot. This async platform_data support is just targeted at stuff that
is fixed on to the board, so as you note it's reasonable to expect to be
able to bind to it if the bus itself is instantiated by the same file
synchronously.

I have sent a working RFC patchset to the lists now which implements
platform support for generic async platform_data; usb core and usbnet
specific platform_data; and finally board definition support for Panda
onboard usbnet device by leveraging the introduced generic support.
Beagle XM also has the same issues that can be solved by async
platform_data from the board definition file.

-Andy