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Based on kernel version 3.16. Page generated on 2014-08-06 21:35 EST.

1	What:		/sys/class/net/<iface>/cdc_ncm/min_tx_pkt
2	Date:		May 2014
3	KernelVersion:	3.16
4	Contact:	Bjørn Mork <bjorn@mork.no>
5	Description:
6			The driver will pad NCM Transfer Blocks (NTBs) longer
7			than this to tx_max, allowing the device to receive
8			tx_max sized frames with no terminating short
9			packet. NTBs shorter than this limit are transmitted
10			as-is, without any padding, and are terminated with a
11			short USB packet.
12	
13			Padding to tx_max allows the driver to transmit NTBs
14			back-to-back without any interleaving short USB
15			packets.  This reduces the number of short packet
16			interrupts in the device, and represents a tradeoff
17			between USB bus bandwidth and device DMA optimization.
18	
19			Set to 0 to pad all frames. Set greater than tx_max to
20			disable all padding.
21	
22	What:		/sys/class/net/<iface>/cdc_ncm/rx_max
23	Date:		May 2014
24	KernelVersion:	3.16
25	Contact:	Bjørn Mork <bjorn@mork.no>
26	Description:
27			The maximum NTB size for RX.  Cannot exceed the
28			maximum value supported by the device. Must allow at
29			least one max sized datagram plus headers.
30	
31			The actual limits are device dependent.  See
32			dwNtbInMaxSize.
33	
34			Note: Some devices will silently ignore changes to
35			this value, resulting in oversized NTBs and
36			corresponding framing errors.
37	
38	What:		/sys/class/net/<iface>/cdc_ncm/tx_max
39	Date:		May 2014
40	KernelVersion:	3.16
41	Contact:	Bjørn Mork <bjorn@mork.no>
42	Description:
43			The maximum NTB size for TX.  Cannot exceed the
44			maximum value supported by the device.  Must allow at
45			least one max sized datagram plus headers.
46	
47			The actual limits are device dependent.  See
48			dwNtbOutMaxSize.
49	
50	What:		/sys/class/net/<iface>/cdc_ncm/tx_timer_usecs
51	Date:		May 2014
52	KernelVersion:	3.16
53	Contact:	Bjørn Mork <bjorn@mork.no>
54	Description:
55			Datagram aggregation timeout in µs. The driver will
56			wait up to 3 times this timeout for more datagrams to
57			aggregate before transmitting an NTB frame.
58	
59			Valid range: 5 to 4000000
60	
61			Set to 0 to disable aggregation.
62	
63	The following read-only attributes all represent fields of the
64	structure defined in section 6.2.1 "GetNtbParameters" of "Universal
65	Serial Bus Communications Class Subclass Specifications for Network
66	Control Model Devices" (CDC NCM), Revision 1.0 (Errata 1), November
67	24, 2010 from USB Implementers Forum, Inc.  The descriptions are
68	quoted from table 6-3 of CDC NCM: "NTB Parameter Structure".
69	
70	What:		/sys/class/net/<iface>/cdc_ncm/bmNtbFormatsSupported
71	Date:		May 2014
72	KernelVersion:	3.16
73	Contact:	Bjørn Mork <bjorn@mork.no>
74	Description:
75			Bit 0: 16-bit NTB supported (set to 1)
76			Bit 1: 32-bit NTB supported
77			Bits 2 â 15: reserved (reset to zero; must be ignored by host)
78	
79	What:		/sys/class/net/<iface>/cdc_ncm/dwNtbInMaxSize
80	Date:		May 2014
81	KernelVersion:	3.16
82	Contact:	Bjørn Mork <bjorn@mork.no>
83	Description:
84			IN NTB Maximum Size in bytes
85	
86	What:		/sys/class/net/<iface>/cdc_ncm/wNdpInDivisor
87	Date:		May 2014
88	KernelVersion:	3.16
89	Contact:	Bjørn Mork <bjorn@mork.no>
90	Description:
91			Divisor used for IN NTB Datagram payload alignment
92	
93	What:		/sys/class/net/<iface>/cdc_ncm/wNdpInPayloadRemainder
94	Date:		May 2014
95	KernelVersion:	3.16
96	Contact:	Bjørn Mork <bjorn@mork.no>
97	Description:
98			Remainder used to align input datagram payload within
99			the NTB: (Payload Offset) mod (wNdpInDivisor) =
100			wNdpInPayloadRemainder
101	
102	What:		/sys/class/net/<iface>/cdc_ncm/wNdpInAlignment
103	Date:		May 2014
104	KernelVersion:	3.16
105	Contact:	Bjørn Mork <bjorn@mork.no>
106	Description:
107			NDP alignment modulus for NTBs on the IN pipe. Shall
108			be a power of 2, and shall be at least 4.
109	
110	What:		/sys/class/net/<iface>/cdc_ncm/dwNtbOutMaxSize
111	Date:		May 2014
112	KernelVersion:	3.16
113	Contact:	Bjørn Mork <bjorn@mork.no>
114	Description:
115			OUT NTB Maximum Size
116	
117	What:		/sys/class/net/<iface>/cdc_ncm/wNdpOutDivisor
118	Date:		May 2014
119	KernelVersion:	3.16
120	Contact:	Bjørn Mork <bjorn@mork.no>
121	Description:
122			OUT NTB Datagram alignment modulus
123	
124	What:		/sys/class/net/<iface>/cdc_ncm/wNdpOutPayloadRemainder
125	Date:		May 2014
126	KernelVersion:	3.16
127	Contact:	Bjørn Mork <bjorn@mork.no>
128	Description:
129			Remainder used to align output datagram payload
130			offsets within the NTB: Padding, shall be transmitted
131			as zero by function, and ignored by host.  (Payload
132			Offset) mod (wNdpOutDivisor) = wNdpOutPayloadRemainder
133	
134	What:		/sys/class/net/<iface>/cdc_ncm/wNdpOutAlignment
135	Date:		May 2014
136	KernelVersion:	3.16
137	Contact:	Bjørn Mork <bjorn@mork.no>
138	Description:
139			NDP alignment modulus for use in NTBs on the OUT
140			pipe. Shall be a power of 2, and shall be at least 4.
141	
142	What:		/sys/class/net/<iface>/cdc_ncm/wNtbOutMaxDatagrams
143	Date:		May 2014
144	KernelVersion:	3.16
145	Contact:	Bjørn Mork <bjorn@mork.no>
146	Description:
147			Maximum number of datagrams that the host may pack
148			into a single OUT NTB. Zero means that the device
149			imposes no limit.
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