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Based on kernel version 4.7.2. Page generated on 2016-08-22 22:39 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/ndp_to_end
23	Date:		Dec 2015
24	KernelVersion:	4.5
25	Contact:	Bjørn Mork <bjorn@mork.no>
26	Description:
27			Boolean attribute showing the status of the "NDP to
28			end" quirk.  Defaults to 'N', except for devices
29			already known to need it enabled.
30	
31			The "NDP to end" quirk makes the driver place the NDP
32			(the packet index table) after the payload.  The NCM
33			specification does not mandate this, but some devices
34			are known to be more restrictive. Write 'Y' to this
35			attribute for temporary testing of a suspect device
36			failing to work with the default driver settings.
37	
38			A device entry should be added to the driver if this
39			quirk is found to be required.
40	
41	What:		/sys/class/net/<iface>/cdc_ncm/rx_max
42	Date:		May 2014
43	KernelVersion:	3.16
44	Contact:	Bjørn Mork <bjorn@mork.no>
45	Description:
46			The maximum NTB size for RX.  Cannot exceed the
47			maximum value supported by the device. Must allow at
48			least one max sized datagram plus headers.
49	
50			The actual limits are device dependent.  See
51			dwNtbInMaxSize.
52	
53			Note: Some devices will silently ignore changes to
54			this value, resulting in oversized NTBs and
55			corresponding framing errors.
56	
57	What:		/sys/class/net/<iface>/cdc_ncm/tx_max
58	Date:		May 2014
59	KernelVersion:	3.16
60	Contact:	Bjørn Mork <bjorn@mork.no>
61	Description:
62			The maximum NTB size for TX.  Cannot exceed the
63			maximum value supported by the device.  Must allow at
64			least one max sized datagram plus headers.
65	
66			The actual limits are device dependent.  See
67			dwNtbOutMaxSize.
68	
69	What:		/sys/class/net/<iface>/cdc_ncm/tx_timer_usecs
70	Date:		May 2014
71	KernelVersion:	3.16
72	Contact:	Bjørn Mork <bjorn@mork.no>
73	Description:
74			Datagram aggregation timeout in µs. The driver will
75			wait up to 3 times this timeout for more datagrams to
76			aggregate before transmitting an NTB frame.
77	
78			Valid range: 5 to 4000000
79	
80			Set to 0 to disable aggregation.
81	
82	The following read-only attributes all represent fields of the
83	structure defined in section 6.2.1 "GetNtbParameters" of "Universal
84	Serial Bus Communications Class Subclass Specifications for Network
85	Control Model Devices" (CDC NCM), Revision 1.0 (Errata 1), November
86	24, 2010 from USB Implementers Forum, Inc.  The descriptions are
87	quoted from table 6-3 of CDC NCM: "NTB Parameter Structure".
88	
89	What:		/sys/class/net/<iface>/cdc_ncm/bmNtbFormatsSupported
90	Date:		May 2014
91	KernelVersion:	3.16
92	Contact:	Bjørn Mork <bjorn@mork.no>
93	Description:
94			Bit 0: 16-bit NTB supported (set to 1)
95			Bit 1: 32-bit NTB supported
96			Bits 2 – 15: reserved (reset to zero; must be ignored by host)
97	
98	What:		/sys/class/net/<iface>/cdc_ncm/dwNtbInMaxSize
99	Date:		May 2014
100	KernelVersion:	3.16
101	Contact:	Bjørn Mork <bjorn@mork.no>
102	Description:
103			IN NTB Maximum Size in bytes
104	
105	What:		/sys/class/net/<iface>/cdc_ncm/wNdpInDivisor
106	Date:		May 2014
107	KernelVersion:	3.16
108	Contact:	Bjørn Mork <bjorn@mork.no>
109	Description:
110			Divisor used for IN NTB Datagram payload alignment
111	
112	What:		/sys/class/net/<iface>/cdc_ncm/wNdpInPayloadRemainder
113	Date:		May 2014
114	KernelVersion:	3.16
115	Contact:	Bjørn Mork <bjorn@mork.no>
116	Description:
117			Remainder used to align input datagram payload within
118			the NTB: (Payload Offset) mod (wNdpInDivisor) =
119			wNdpInPayloadRemainder
120	
121	What:		/sys/class/net/<iface>/cdc_ncm/wNdpInAlignment
122	Date:		May 2014
123	KernelVersion:	3.16
124	Contact:	Bjørn Mork <bjorn@mork.no>
125	Description:
126			NDP alignment modulus for NTBs on the IN pipe. Shall
127			be a power of 2, and shall be at least 4.
128	
129	What:		/sys/class/net/<iface>/cdc_ncm/dwNtbOutMaxSize
130	Date:		May 2014
131	KernelVersion:	3.16
132	Contact:	Bjørn Mork <bjorn@mork.no>
133	Description:
134			OUT NTB Maximum Size
135	
136	What:		/sys/class/net/<iface>/cdc_ncm/wNdpOutDivisor
137	Date:		May 2014
138	KernelVersion:	3.16
139	Contact:	Bjørn Mork <bjorn@mork.no>
140	Description:
141			OUT NTB Datagram alignment modulus
142	
143	What:		/sys/class/net/<iface>/cdc_ncm/wNdpOutPayloadRemainder
144	Date:		May 2014
145	KernelVersion:	3.16
146	Contact:	Bjørn Mork <bjorn@mork.no>
147	Description:
148			Remainder used to align output datagram payload
149			offsets within the NTB: Padding, shall be transmitted
150			as zero by function, and ignored by host.  (Payload
151			Offset) mod (wNdpOutDivisor) = wNdpOutPayloadRemainder
152	
153	What:		/sys/class/net/<iface>/cdc_ncm/wNdpOutAlignment
154	Date:		May 2014
155	KernelVersion:	3.16
156	Contact:	Bjørn Mork <bjorn@mork.no>
157	Description:
158			NDP alignment modulus for use in NTBs on the OUT
159			pipe. Shall be a power of 2, and shall be at least 4.
160	
161	What:		/sys/class/net/<iface>/cdc_ncm/wNtbOutMaxDatagrams
162	Date:		May 2014
163	KernelVersion:	3.16
164	Contact:	Bjørn Mork <bjorn@mork.no>
165	Description:
166			Maximum number of datagrams that the host may pack
167			into a single OUT NTB. Zero means that the device
168			imposes no limit.
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