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-rw-r--r--Documentation/networking/can.txt235
-rw-r--r--Documentation/networking/ip-sysctl.txt11
-rw-r--r--Documentation/networking/mac80211-injection.txt28
3 files changed, 213 insertions, 61 deletions
diff --git a/Documentation/networking/can.txt b/Documentation/networking/can.txt
index 2035bc4932f2..6cd6627c3293 100644
--- a/Documentation/networking/can.txt
+++ b/Documentation/networking/can.txt
@@ -36,10 +36,15 @@ This file contains
36 6.2 local loopback of sent frames 36 6.2 local loopback of sent frames
37 6.3 CAN controller hardware filters 37 6.3 CAN controller hardware filters
38 6.4 The virtual CAN driver (vcan) 38 6.4 The virtual CAN driver (vcan)
39 6.5 currently supported CAN hardware 39 6.5 The CAN network device driver interface
40 6.6 todo 40 6.5.1 Netlink interface to set/get devices properties
41 6.5.2 Setting the CAN bit-timing
42 6.5.3 Starting and stopping the CAN network device
43 6.6 supported CAN hardware
41 44
42 7 Credits 45 7 Socket CAN resources
46
47 8 Credits
43 48
44============================================================================ 49============================================================================
45 50
@@ -234,6 +239,8 @@ solution for a couple of reasons:
234 the user application using the common CAN filter mechanisms. Inside 239 the user application using the common CAN filter mechanisms. Inside
235 this filter definition the (interested) type of errors may be 240 this filter definition the (interested) type of errors may be
236 selected. The reception of error frames is disabled by default. 241 selected. The reception of error frames is disabled by default.
242 The format of the CAN error frame is briefly decribed in the Linux
243 header file "include/linux/can/error.h".
237 244
2384. How to use Socket CAN 2454. How to use Socket CAN
239------------------------ 246------------------------
@@ -605,61 +612,213 @@ solution for a couple of reasons:
605 removal of vcan network devices can be managed with the ip(8) tool: 612 removal of vcan network devices can be managed with the ip(8) tool:
606 613
607 - Create a virtual CAN network interface: 614 - Create a virtual CAN network interface:
608 ip link add type vcan 615 $ ip link add type vcan
609 616
610 - Create a virtual CAN network interface with a specific name 'vcan42': 617 - Create a virtual CAN network interface with a specific name 'vcan42':
611 ip link add dev vcan42 type vcan 618 $ ip link add dev vcan42 type vcan
612 619
613 - Remove a (virtual CAN) network interface 'vcan42': 620 - Remove a (virtual CAN) network interface 'vcan42':
614 ip link del vcan42 621 $ ip link del vcan42
615 622
616 The tool 'vcan' from the SocketCAN SVN repository on BerliOS is obsolete. 623 6.5 The CAN network device driver interface
617 624
618 Virtual CAN network device creation in older Kernels: 625 The CAN network device driver interface provides a generic interface
619 In Linux Kernel versions < 2.6.24 the vcan driver creates 4 vcan 626 to setup, configure and monitor CAN network devices. The user can then
620 netdevices at module load time by default. This value can be changed 627 configure the CAN device, like setting the bit-timing parameters, via
621 with the module parameter 'numdev'. E.g. 'modprobe vcan numdev=8' 628 the netlink interface using the program "ip" from the "IPROUTE2"
622 629 utility suite. The following chapter describes briefly how to use it.
623 6.5 currently supported CAN hardware 630 Furthermore, the interface uses a common data structure and exports a
631 set of common functions, which all real CAN network device drivers
632 should use. Please have a look to the SJA1000 or MSCAN driver to
633 understand how to use them. The name of the module is can-dev.ko.
634
635 6.5.1 Netlink interface to set/get devices properties
636
637 The CAN device must be configured via netlink interface. The supported
638 netlink message types are defined and briefly described in
639 "include/linux/can/netlink.h". CAN link support for the program "ip"
640 of the IPROUTE2 utility suite is avaiable and it can be used as shown
641 below:
642
643 - Setting CAN device properties:
644
645 $ ip link set can0 type can help
646 Usage: ip link set DEVICE type can
647 [ bitrate BITRATE [ sample-point SAMPLE-POINT] ] |
648 [ tq TQ prop-seg PROP_SEG phase-seg1 PHASE-SEG1
649 phase-seg2 PHASE-SEG2 [ sjw SJW ] ]
650
651 [ loopback { on | off } ]
652 [ listen-only { on | off } ]
653 [ triple-sampling { on | off } ]
654
655 [ restart-ms TIME-MS ]
656 [ restart ]
657
658 Where: BITRATE := { 1..1000000 }
659 SAMPLE-POINT := { 0.000..0.999 }
660 TQ := { NUMBER }
661 PROP-SEG := { 1..8 }
662 PHASE-SEG1 := { 1..8 }
663 PHASE-SEG2 := { 1..8 }
664 SJW := { 1..4 }
665 RESTART-MS := { 0 | NUMBER }
666
667 - Display CAN device details and statistics:
668
669 $ ip -details -statistics link show can0
670 2: can0: <NOARP,UP,LOWER_UP,ECHO> mtu 16 qdisc pfifo_fast state UP qlen 10
671 link/can
672 can <TRIPLE-SAMPLING> state ERROR-ACTIVE restart-ms 100
673 bitrate 125000 sample_point 0.875
674 tq 125 prop-seg 6 phase-seg1 7 phase-seg2 2 sjw 1
675 sja1000: tseg1 1..16 tseg2 1..8 sjw 1..4 brp 1..64 brp-inc 1
676 clock 8000000
677 re-started bus-errors arbit-lost error-warn error-pass bus-off
678 41 17457 0 41 42 41
679 RX: bytes packets errors dropped overrun mcast
680 140859 17608 17457 0 0 0
681 TX: bytes packets errors dropped carrier collsns
682 861 112 0 41 0 0
683
684 More info to the above output:
685
686 "<TRIPLE-SAMPLING>"
687 Shows the list of selected CAN controller modes: LOOPBACK,
688 LISTEN-ONLY, or TRIPLE-SAMPLING.
689
690 "state ERROR-ACTIVE"
691 The current state of the CAN controller: "ERROR-ACTIVE",
692 "ERROR-WARNING", "ERROR-PASSIVE", "BUS-OFF" or "STOPPED"
693
694 "restart-ms 100"
695 Automatic restart delay time. If set to a non-zero value, a
696 restart of the CAN controller will be triggered automatically
697 in case of a bus-off condition after the specified delay time
698 in milliseconds. By default it's off.
699
700 "bitrate 125000 sample_point 0.875"
701 Shows the real bit-rate in bits/sec and the sample-point in the
702 range 0.000..0.999. If the calculation of bit-timing parameters
703 is enabled in the kernel (CONFIG_CAN_CALC_BITTIMING=y), the
704 bit-timing can be defined by setting the "bitrate" argument.
705 Optionally the "sample-point" can be specified. By default it's
706 0.000 assuming CIA-recommended sample-points.
707
708 "tq 125 prop-seg 6 phase-seg1 7 phase-seg2 2 sjw 1"
709 Shows the time quanta in ns, propagation segment, phase buffer
710 segment 1 and 2 and the synchronisation jump width in units of
711 tq. They allow to define the CAN bit-timing in a hardware
712 independent format as proposed by the Bosch CAN 2.0 spec (see
713 chapter 8 of http://www.semiconductors.bosch.de/pdf/can2spec.pdf).
714
715 "sja1000: tseg1 1..16 tseg2 1..8 sjw 1..4 brp 1..64 brp-inc 1
716 clock 8000000"
717 Shows the bit-timing constants of the CAN controller, here the
718 "sja1000". The minimum and maximum values of the time segment 1
719 and 2, the synchronisation jump width in units of tq, the
720 bitrate pre-scaler and the CAN system clock frequency in Hz.
721 These constants could be used for user-defined (non-standard)
722 bit-timing calculation algorithms in user-space.
723
724 "re-started bus-errors arbit-lost error-warn error-pass bus-off"
725 Shows the number of restarts, bus and arbitration lost errors,
726 and the state changes to the error-warning, error-passive and
727 bus-off state. RX overrun errors are listed in the "overrun"
728 field of the standard network statistics.
729
730 6.5.2 Setting the CAN bit-timing
731
732 The CAN bit-timing parameters can always be defined in a hardware
733 independent format as proposed in the Bosch CAN 2.0 specification
734 specifying the arguments "tq", "prop_seg", "phase_seg1", "phase_seg2"
735 and "sjw":
736
737 $ ip link set canX type can tq 125 prop-seg 6 \
738 phase-seg1 7 phase-seg2 2 sjw 1
739
740 If the kernel option CONFIG_CAN_CALC_BITTIMING is enabled, CIA
741 recommended CAN bit-timing parameters will be calculated if the bit-
742 rate is specified with the argument "bitrate":
743
744 $ ip link set canX type can bitrate 125000
745
746 Note that this works fine for the most common CAN controllers with
747 standard bit-rates but may *fail* for exotic bit-rates or CAN system
748 clock frequencies. Disabling CONFIG_CAN_CALC_BITTIMING saves some
749 space and allows user-space tools to solely determine and set the
750 bit-timing parameters. The CAN controller specific bit-timing
751 constants can be used for that purpose. They are listed by the
752 following command:
753
754 $ ip -details link show can0
755 ...
756 sja1000: clock 8000000 tseg1 1..16 tseg2 1..8 sjw 1..4 brp 1..64 brp-inc 1
757
758 6.5.3 Starting and stopping the CAN network device
759
760 A CAN network device is started or stopped as usual with the command
761 "ifconfig canX up/down" or "ip link set canX up/down". Be aware that
762 you *must* define proper bit-timing parameters for real CAN devices
763 before you can start it to avoid error-prone default settings:
764
765 $ ip link set canX up type can bitrate 125000
766
767 A device may enter the "bus-off" state if too much errors occurred on
768 the CAN bus. Then no more messages are received or sent. An automatic
769 bus-off recovery can be enabled by setting the "restart-ms" to a
770 non-zero value, e.g.:
771
772 $ ip link set canX type can restart-ms 100
773
774 Alternatively, the application may realize the "bus-off" condition
775 by monitoring CAN error frames and do a restart when appropriate with
776 the command:
777
778 $ ip link set canX type can restart
779
780 Note that a restart will also create a CAN error frame (see also
781 chapter 3.4).
624 782
625 On the project website http://developer.berlios.de/projects/socketcan 783 6.6 Supported CAN hardware
626 there are different drivers available:
627 784
628 vcan: Virtual CAN interface driver (if no real hardware is available) 785 Please check the "Kconfig" file in "drivers/net/can" to get an actual
629 sja1000: Philips SJA1000 CAN controller (recommended) 786 list of the support CAN hardware. On the Socket CAN project website
630 i82527: Intel i82527 CAN controller 787 (see chapter 7) there might be further drivers available, also for
631 mscan: Motorola/Freescale CAN controller (e.g. inside SOC MPC5200) 788 older kernel versions.
632 ccan: CCAN controller core (e.g. inside SOC h7202)
633 slcan: For a bunch of CAN adaptors that are attached via a
634 serial line ASCII protocol (for serial / USB adaptors)
635 789
636 Additionally the different CAN adaptors (ISA/PCI/PCMCIA/USB/Parport) 7907. Socket CAN resources
637 from PEAK Systemtechnik support the CAN netdevice driver model 791-----------------------
638 since Linux driver v6.0: http://www.peak-system.com/linux/index.htm
639 792
640 Please check the Mailing Lists on the berlios OSS project website. 793 You can find further resources for Socket CAN like user space tools,
794 support for old kernel versions, more drivers, mailing lists, etc.
795 at the BerliOS OSS project website for Socket CAN:
641 796
642 6.6 todo 797 http://developer.berlios.de/projects/socketcan
643 798
644 The configuration interface for CAN network drivers is still an open 799 If you have questions, bug fixes, etc., don't hesitate to post them to
645 issue that has not been finalized in the socketcan project. Also the 800 the Socketcan-Users mailing list. But please search the archives first.
646 idea of having a library module (candev.ko) that holds functions
647 that are needed by all CAN netdevices is not ready to ship.
648 Your contribution is welcome.
649 801
6507. Credits 8028. Credits
651---------- 803----------
652 804
653 Oliver Hartkopp (PF_CAN core, filters, drivers, bcm) 805 Oliver Hartkopp (PF_CAN core, filters, drivers, bcm, SJA1000 driver)
654 Urs Thuermann (PF_CAN core, kernel integration, socket interfaces, raw, vcan) 806 Urs Thuermann (PF_CAN core, kernel integration, socket interfaces, raw, vcan)
655 Jan Kizka (RT-SocketCAN core, Socket-API reconciliation) 807 Jan Kizka (RT-SocketCAN core, Socket-API reconciliation)
656 Wolfgang Grandegger (RT-SocketCAN core & drivers, Raw Socket-API reviews) 808 Wolfgang Grandegger (RT-SocketCAN core & drivers, Raw Socket-API reviews,
809 CAN device driver interface, MSCAN driver)
657 Robert Schwebel (design reviews, PTXdist integration) 810 Robert Schwebel (design reviews, PTXdist integration)
658 Marc Kleine-Budde (design reviews, Kernel 2.6 cleanups, drivers) 811 Marc Kleine-Budde (design reviews, Kernel 2.6 cleanups, drivers)
659 Benedikt Spranger (reviews) 812 Benedikt Spranger (reviews)
660 Thomas Gleixner (LKML reviews, coding style, posting hints) 813 Thomas Gleixner (LKML reviews, coding style, posting hints)
661 Andrey Volkov (kernel subtree structure, ioctls, mscan driver) 814 Andrey Volkov (kernel subtree structure, ioctls, MSCAN driver)
662 Matthias Brukner (first SJA1000 CAN netdevice implementation Q2/2003) 815 Matthias Brukner (first SJA1000 CAN netdevice implementation Q2/2003)
663 Klaus Hitschler (PEAK driver integration) 816 Klaus Hitschler (PEAK driver integration)
664 Uwe Koppe (CAN netdevices with PF_PACKET approach) 817 Uwe Koppe (CAN netdevices with PF_PACKET approach)
665 Michael Schulze (driver layer loopback requirement, RT CAN drivers review) 818 Michael Schulze (driver layer loopback requirement, RT CAN drivers review)
819 Pavel Pisa (Bit-timing calculation)
820 Sascha Hauer (SJA1000 platform driver)
821 Sebastian Haas (SJA1000 EMS PCI driver)
822 Markus Plessing (SJA1000 EMS PCI driver)
823 Per Dalen (SJA1000 Kvaser PCI driver)
824 Sam Ravnborg (reviews, coding style, kbuild help)
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index b121c5db707f..3ffd233c369c 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -168,7 +168,16 @@ tcp_dsack - BOOLEAN
168 Allows TCP to send "duplicate" SACKs. 168 Allows TCP to send "duplicate" SACKs.
169 169
170tcp_ecn - BOOLEAN 170tcp_ecn - BOOLEAN
171 Enable Explicit Congestion Notification in TCP. 171 Enable Explicit Congestion Notification (ECN) in TCP. ECN is only
172 used when both ends of the TCP flow support it. It is useful to
173 avoid losses due to congestion (when the bottleneck router supports
174 ECN).
175 Possible values are:
176 0 disable ECN
177 1 ECN enabled
178 2 Only server-side ECN enabled. If the other end does
179 not support ECN, behavior is like with ECN disabled.
180 Default: 2
172 181
173tcp_fack - BOOLEAN 182tcp_fack - BOOLEAN
174 Enable FACK congestion avoidance and fast retransmission. 183 Enable FACK congestion avoidance and fast retransmission.
diff --git a/Documentation/networking/mac80211-injection.txt b/Documentation/networking/mac80211-injection.txt
index 84906ef3ed6e..b30e81ad5307 100644
--- a/Documentation/networking/mac80211-injection.txt
+++ b/Documentation/networking/mac80211-injection.txt
@@ -12,38 +12,22 @@ following format:
12The radiotap format is discussed in 12The radiotap format is discussed in
13./Documentation/networking/radiotap-headers.txt. 13./Documentation/networking/radiotap-headers.txt.
14 14
15Despite 13 radiotap argument types are currently defined, most only make sense 15Despite many radiotap parameters being currently defined, most only make sense
16to appear on received packets. The following information is parsed from the 16to appear on received packets. The following information is parsed from the
17radiotap headers and used to control injection: 17radiotap headers and used to control injection:
18 18
19 * IEEE80211_RADIOTAP_RATE
20
21 rate in 500kbps units, automatic if invalid or not present
22
23
24 * IEEE80211_RADIOTAP_ANTENNA
25
26 antenna to use, automatic if not present
27
28
29 * IEEE80211_RADIOTAP_DBM_TX_POWER
30
31 transmit power in dBm, automatic if not present
32
33
34 * IEEE80211_RADIOTAP_FLAGS 19 * IEEE80211_RADIOTAP_FLAGS
35 20
36 IEEE80211_RADIOTAP_F_FCS: FCS will be removed and recalculated 21 IEEE80211_RADIOTAP_F_FCS: FCS will be removed and recalculated
37 IEEE80211_RADIOTAP_F_WEP: frame will be encrypted if key available 22 IEEE80211_RADIOTAP_F_WEP: frame will be encrypted if key available
38 IEEE80211_RADIOTAP_F_FRAG: frame will be fragmented if longer than the 23 IEEE80211_RADIOTAP_F_FRAG: frame will be fragmented if longer than the
39 current fragmentation threshold. Note that 24 current fragmentation threshold.
40 this flag is only reliable when software 25
41 fragmentation is enabled)
42 26
43The injection code can also skip all other currently defined radiotap fields 27The injection code can also skip all other currently defined radiotap fields
44facilitating replay of captured radiotap headers directly. 28facilitating replay of captured radiotap headers directly.
45 29
46Here is an example valid radiotap header defining these three parameters 30Here is an example valid radiotap header defining some parameters
47 31
48 0x00, 0x00, // <-- radiotap version 32 0x00, 0x00, // <-- radiotap version
49 0x0b, 0x00, // <- radiotap header length 33 0x0b, 0x00, // <- radiotap header length
@@ -72,8 +56,8 @@ interface), along the following lines:
72... 56...
73 r = pcap_inject(ppcap, u8aSendBuffer, nLength); 57 r = pcap_inject(ppcap, u8aSendBuffer, nLength);
74 58
75You can also find sources for a complete inject test applet here: 59You can also find a link to a complete inject application here:
76 60
77http://penumbra.warmcat.com/_twk/tiki-index.php?page=packetspammer 61http://wireless.kernel.org/en/users/Documentation/packetspammer
78 62
79Andy Green <andy@warmcat.com> 63Andy Green <andy@warmcat.com>