linux-imx/Documentation/ABI/testing/sysfs-class-net-cdc_ncm
Mauro Carvalho Chehab 54a19b4d3f docs: ABI: cleanup several ABI documents
There are some ABI documents that, while they don't generate
any warnings, they have issues when parsed by get_abi.pl script
on its output result.

Address them, in order to provide a clean output.

Reviewed-by: Tom Rix <trix@redhat.com> # for fpga-manager
Reviewed-By: Kajol Jain<kjain@linux.ibm.com> # for sysfs-bus-event_source-devices-hv_gpci and sysfs-bus-event_source-devices-hv_24x7
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> #for IIO
Acked-by: Oded Gabbay <oded.gabbay@gmail.com> # for Habanalabs
Acked-by: Vaibhav Jain <vaibhav@linux.ibm.com> # for sysfs-bus-papr-pmem
Acked-by: Cezary Rojewski <cezary.rojewski@intel.com> # for catpt
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Ilya Dryomov <idryomov@gmail.com> # for rbd
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/5bc78e5b68ed1e9e39135173857cb2e753be868f.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30 13:14:29 +01:00

5.3 KiB
Raw Blame History

What: /sys/class/net//cdc_ncm/min_tx_pkt Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: The driver will pad NCM Transfer Blocks (NTBs) longer than this to tx_max, allowing the device to receive tx_max sized frames with no terminating short packet. NTBs shorter than this limit are transmitted as-is, without any padding, and are terminated with a short USB packet.

	Padding to tx_max allows the driver to transmit NTBs
	back-to-back without any interleaving short USB
	packets.  This reduces the number of short packet
	interrupts in the device, and represents a tradeoff
	between USB bus bandwidth and device DMA optimization.

	Set to 0 to pad all frames. Set greater than tx_max to
	disable all padding.

What: /sys/class/net//cdc_ncm/ndp_to_end Date: Dec 2015 KernelVersion: 4.5 Contact: Bjørn Mork bjorn@mork.no Description: Boolean attribute showing the status of the "NDP to end" quirk. Defaults to 'N', except for devices already known to need it enabled.

	The "NDP to end" quirk makes the driver place the NDP
	(the packet index table) after the payload.  The NCM
	specification does not mandate this, but some devices
	are known to be more restrictive. Write 'Y' to this
	attribute for temporary testing of a suspect device
	failing to work with the default driver settings.

	A device entry should be added to the driver if this
	quirk is found to be required.

What: /sys/class/net//cdc_ncm/rx_max Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: The maximum NTB size for RX. Cannot exceed the maximum value supported by the device. Must allow at least one max sized datagram plus headers.

	The actual limits are device dependent.  See
	dwNtbInMaxSize.

	Note: Some devices will silently ignore changes to
	this value, resulting in oversized NTBs and
	corresponding framing errors.

What: /sys/class/net//cdc_ncm/tx_max Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: The maximum NTB size for TX. Cannot exceed the maximum value supported by the device. Must allow at least one max sized datagram plus headers.

	The actual limits are device dependent.  See
	dwNtbOutMaxSize.

What: /sys/class/net//cdc_ncm/tx_timer_usecs Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: Datagram aggregation timeout in µs. The driver will wait up to 3 times this timeout for more datagrams to aggregate before transmitting an NTB frame.

	Valid range: 5 to 4000000

	Set to 0 to disable aggregation.

The following read-only attributes all represent fields of the structure defined in section 6.2.1 "GetNtbParameters" of "Universal Serial Bus Communications Class Subclass Specifications for Network Control Model Devices" (CDC NCM), Revision 1.0 (Errata 1), November 24, 2010 from USB Implementers Forum, Inc. The descriptions are quoted from table 6-3 of CDC NCM: "NTB Parameter Structure".

What: /sys/class/net//cdc_ncm/bmNtbFormatsSupported Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: - Bit 0: 16-bit NTB supported (set to 1) - Bit 1: 32-bit NTB supported - Bits 2 15: reserved (reset to zero; must be ignored by host)

What: /sys/class/net//cdc_ncm/dwNtbInMaxSize Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: IN NTB Maximum Size in bytes

What: /sys/class/net//cdc_ncm/wNdpInDivisor Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: Divisor used for IN NTB Datagram payload alignment

What: /sys/class/net//cdc_ncm/wNdpInPayloadRemainder Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: Remainder used to align input datagram payload within the NTB: (Payload Offset) mod (wNdpInDivisor) = wNdpInPayloadRemainder

What: /sys/class/net//cdc_ncm/wNdpInAlignment Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: NDP alignment modulus for NTBs on the IN pipe. Shall be a power of 2, and shall be at least 4.

What: /sys/class/net//cdc_ncm/dwNtbOutMaxSize Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: OUT NTB Maximum Size

What: /sys/class/net//cdc_ncm/wNdpOutDivisor Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: OUT NTB Datagram alignment modulus

What: /sys/class/net//cdc_ncm/wNdpOutPayloadRemainder Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: Remainder used to align output datagram payload offsets within the NTB: Padding, shall be transmitted as zero by function, and ignored by host. (Payload Offset) mod (wNdpOutDivisor) = wNdpOutPayloadRemainder

What: /sys/class/net//cdc_ncm/wNdpOutAlignment Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: NDP alignment modulus for use in NTBs on the OUT pipe. Shall be a power of 2, and shall be at least 4.

What: /sys/class/net//cdc_ncm/wNtbOutMaxDatagrams Date: May 2014 KernelVersion: 3.16 Contact: Bjørn Mork bjorn@mork.no Description: Maximum number of datagrams that the host may pack into a single OUT NTB. Zero means that the device imposes no limit.