[usb_gadget p00] Classes for encoding USB descriptors.

[usb_gadget p00] Classes for encoding USB descriptors.

The descriptor module defines a generic infrastructure for declaring USB
descriptor formats. Features such as fixed and computed descriptor
fields are intended to make it as easy as possible to construct a
well-formed descriptor.

BUG=396682
R=rockot@chromium.org,rpaquay@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=285076

[Ken Rockot(use gerrit already), 2014-07-23 00:03:48]

LGTM - Also you should add an OWNERS file to tools/usb_gadget in this CL. Add
yourself at least, and if you don't want to be the only owner you can add me as
well.

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
File tools/usb_gadget/descriptor.py (right):

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:4: """
Maybe this module should be usb_descriptors?

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:8: import usb_const
How about "usb_constants" for the module name?

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:12: 
A bit of documentation?

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:184: DeviceDescriptor.AddComputedField('bLength',
'B', 'struct_size')
Might as well link to / reference any relevant section(s) of the USB spec from
usb.org here. Here and other places where you build descriptor types.

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:204: class DescriptorContainer(Descriptor):
If this is established nomenclature in USB land, I'm fine with it; otherwise I
think I'd want to call this "CompositeDescriptor." What do you think?

[not at google - send to devlin, 2014-07-23 00:05:44]

same for the other reviews

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
File tools/usb_gadget/descriptor.py (right):

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:1: """USB descriptor generation utilities.
copyright

[Reilly Grant (use Gerrit), 2014-07-23 00:43:55]

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
File tools/usb_gadget/descriptor.py (right):

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:1: """USB descriptor generation utilities.
On 2014/07/23 00:05:44, kalman wrote:
> copyright

Done.

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:4: """
On 2014/07/23 00:03:48, Ken Rockot wrote:
> Maybe this module should be usb_descriptors?

Done.

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:8: import usb_const
On 2014/07/23 00:03:47, Ken Rockot wrote:
> How about "usb_constants" for the module name?

Done.

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:12: 
On 2014/07/23 00:03:47, Ken Rockot wrote:
> A bit of documentation?

Done.

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:184: DeviceDescriptor.AddComputedField('bLength',
'B', 'struct_size')
On 2014/07/23 00:03:47, Ken Rockot wrote:
> Might as well link to / reference any relevant section(s) of the USB spec from
> http://usb.org here. Here and other places where you build descriptor types.

Done.

https://codereview.chromium.org/409883008/diff/20001/tools/usb_gadget/descrip...
tools/usb_gadget/descriptor.py:204: class DescriptorContainer(Descriptor):
On 2014/07/23 00:03:48, Ken Rockot wrote:
> If this is established nomenclature in USB land, I'm fine with it; otherwise I
> think I'd want to call this "CompositeDescriptor." What do you think?

"CompositeDescriptor" may confusing because "USB Composite Device" means a
device with multiple interfaces each implementing a different protocol.

[Reilly Grant (use Gerrit), 2014-07-23 17:30:47]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2014-07-23 17:31:23]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/reillyg@chromium.org/409883008/80001

[commit-bot: I haz the power, 2014-07-23 23:29:45]

Change committed as 285076