PTP Required Commands
PTP drivers must support commands marked as mandatory in the Conformance Section (chapter 14) of the PIMA15740 specification. The only exception is that the GetNumObjects command is not used.
The full list of required PTP commands is:
0x1001 GetDeviceInfo
0x1002 OpenSession
0x1003 CloseSession
0x1004 GetStorageIDs
0x1005 GetStorageInfo
0x1007 GetObjectHandles
0x1008 GetObjectInfo
0x1009 GetObject
0x100A GetThumb