Device Framework Tests
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9.7
BOS and Device Capabilities Descriptor Test
Test Summary
Examiner verifies that all BOS Descriptors are formatted properly, including device capability
sub-descriptors that are returned with BOS Descriptor requests. The test is performed three
times- once each for the default, addressed, and configured states.
Test Steps and Expected Results
1.
Examiner initializes the link to U0.
2.
Examiner issues several standard descriptor requests, followed by a short (5 bytes) BOS
descriptor request and then a longer request based on the value of the wTotalLength field
returned in the first request.
BOS
The first BOS Descriptor request must return at least 5 bytes.
The bLength field in the BOS Descriptor must equal 0x05.
The bNumCaps field in the BOS descriptor must match the number of device
capability descriptors included.
The bDescriptorType field in the BOS Descriptor must be equal to BOS (0x0F).
The second request for the BOS descriptor must return a length equal to
wTotalLength as shown in the returned BOS descriptor data from the first
request.
All Sub-Descriptors
The bDescriptorType field in the all sub-descriptors must be equal to DEVICE
CAPABILITY (0x10).
The bDevCapabilityType field in all sub-descriptors must be equal to USB
EXTENSION (0X02), SUPERSPEED USB (0x03), or CONTAINER ID (0x04).
SuperSpeed USB Sub-Descriptor
