[PATCH 0/2] doc: net: ieee802154: move from plain text to rst

[PATCH 0/2] doc: net: ieee802154: move from plain text to rst

[Stefan Schmidt]

Hello.

The ieee802154 subsystem doc was still in plain text. With the networking book
taking shape I thought it was time to do the first step and move it over to rst.
This really is only the minimal conversion. I need to take some time to update
and extend the docs.

The patches are based on net-next, but they only touch the networking book so I
would not expect and trouble. From what I have seen they would go through
Jonathan's tree after being acked by Dave? If you want this patches against a
different tree let me know.

regards
Stefan Schmidt

Stefan Schmidt (2):
  doc: net: ieee802154: introduce IEEE 802.15.4 subsystem doc in rst
    style
  doc: net: ieee802154: remove old plain text docs after switching to
    rst

 .../{ieee802154.txt => ieee802154.rst}        | 193 +++++++++---------
 Documentation/networking/index.rst            |   1 +
 2 files changed, 99 insertions(+), 95 deletions(-)
 rename Documentation/networking/{ieee802154.txt => ieee802154.rst} (58%)

-- 
2.17.2

[PATCH 1/2] doc: net: ieee802154: introduce IEEE 802.15.4 subsystem doc in rst style

[Stefan Schmidt]

Moving the ieee802154 docs from a plain text file into the new rst
style. This commit only does the minimal needed change to bring the
documentation over. Follow up patches will improve and extend on this.

Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
---
 Documentation/networking/ieee802154.rst | 180 ++++++++++++++++++++++++
 Documentation/networking/index.rst      |   1 +
 2 files changed, 181 insertions(+)
 create mode 100644 Documentation/networking/ieee802154.rst

diff --git a/Documentation/networking/ieee802154.rst b/Documentation/networking/ieee802154.rst
new file mode 100644
index 000000000000..36ca823a1122
--- /dev/null
+++ b/Documentation/networking/ieee802154.rst
@@ -0,0 +1,180 @@
+===============================
+IEEE 802.15.4 Developer's Guide
+===============================
+
+Introduction
+============
+The IEEE 802.15.4 working group focuses on standardization of the bottom
+two layers: Medium Access Control (MAC) and Physical access (PHY). And there
+are mainly two options available for upper layers:
+
+- ZigBee - proprietary protocol from the ZigBee Alliance
+- 6LoWPAN - IPv6 networking over low rate personal area networks
+
+The goal of the Linux-wpan is to provide a complete implementation
+of the IEEE 802.15.4 and 6LoWPAN protocols. IEEE 802.15.4 is a stack
+of protocols for organizing Low-Rate Wireless Personal Area Networks.
+
+The stack is composed of three main parts:
+
+- IEEE 802.15.4 layer;  We have chosen to use plain Berkeley socket API,
+  the generic Linux networking stack to transfer IEEE 802.15.4 data
+  messages and a special protocol over netlink for configuration/management
+- MAC - provides access to shared channel and reliable data delivery
+- PHY - represents device drivers
+
+Socket API
+==========
+
+.. c:function:: int sd = socket(PF_IEEE802154, SOCK_DGRAM, 0);
+
+The address family, socket addresses etc. are defined in the
+include/net/af_ieee802154.h header or in the special header
+in the userspace package (see either http://wpan.cakelab.org/ or the
+git tree at https://github.com/linux-wpan/wpan-tools).
+
+6LoWPAN Linux implementation
+============================
+
+The IEEE 802.15.4 standard specifies an MTU of 127 bytes, yielding about 80
+octets of actual MAC payload once security is turned on, on a wireless link
+with a link throughput of 250 kbps or less.  The 6LoWPAN adaptation format
+[RFC4944] was specified to carry IPv6 datagrams over such constrained links,
+taking into account limited bandwidth, memory, or energy resources that are
+expected in applications such as wireless Sensor Networks.  [RFC4944] defines
+a Mesh Addressing header to support sub-IP forwarding, a Fragmentation header
+to support the IPv6 minimum MTU requirement [RFC2460], and stateless header
+compression for IPv6 datagrams (LOWPAN_HC1 and LOWPAN_HC2) to reduce the
+relatively large IPv6 and UDP headers down to (in the best case) several bytes.
+
+In September 2011 the standard update was published - [RFC6282].
+It deprecates HC1 and HC2 compression and defines IPHC encoding format which is
+used in this Linux implementation.
+
+All the code related to 6lowpan you may find in files: net/6lowpan/*
+and net/ieee802154/6lowpan/*
+
+To setup a 6LoWPAN interface you need:
+1. Add IEEE802.15.4 interface and set channel and PAN ID;
+2. Add 6lowpan interface by command like:
+# ip link add link wpan0 name lowpan0 type lowpan
+3. Bring up 'lowpan0' interface
+
+Drivers
+=======
+
+Like with WiFi, there are several types of devices implementing IEEE 802.15.4.
+1) 'HardMAC'. The MAC layer is implemented in the device itself, the device
+exports a management (e.g. MLME) and data API.
+2) 'SoftMAC' or just radio. These types of devices are just radio transceivers
+possibly with some kinds of acceleration like automatic CRC computation and
+comparation, automagic ACK handling, address matching, etc.
+
+Those types of devices require different approach to be hooked into Linux kernel.
+
+HardMAC
+-------
+
+See the header include/net/ieee802154_netdev.h. You have to implement Linux
+net_device, with .type = ARPHRD_IEEE802154. Data is exchanged with socket family
+code via plain sk_buffs. On skb reception skb->cb must contain additional
+info as described in the struct ieee802154_mac_cb. During packet transmission
+the skb->cb is used to provide additional data to device's header_ops->create
+function. Be aware that this data can be overridden later (when socket code
+submits skb to qdisc), so if you need something from that cb later, you should
+store info in the skb->data on your own.
+
+To hook the MLME interface you have to populate the ml_priv field of your
+net_device with a pointer to struct ieee802154_mlme_ops instance. The fields
+assoc_req, assoc_resp, disassoc_req, start_req, and scan_req are optional.
+All other fields are required.
+
+SoftMAC
+-------
+
+The MAC is the middle layer in the IEEE 802.15.4 Linux stack. This moment it
+provides interface for drivers registration and management of slave interfaces.
+
+NOTE: Currently the only monitor device type is supported - it's IEEE 802.15.4
+stack interface for network sniffers (e.g. WireShark).
+
+This layer is going to be extended soon.
+
+See header include/net/mac802154.h and several drivers in
+drivers/net/ieee802154/.
+
+Fake drivers
+------------
+
+In addition there is a driver available which simulates a real device with
+SoftMAC (fakelb - IEEE 802.15.4 loopback driver) interface. This option
+provides a possibility to test and debug the stack without usage of real hardware.
+
+Device drivers API
+==================
+
+The include/net/mac802154.h defines following functions:
+
+.. c:function:: struct ieee802154_dev *ieee802154_alloc_device (size_t priv_size, struct ieee802154_ops *ops)
+
+Allocation of IEEE 802.15.4 compatible device.
+
+.. c:function:: void ieee802154_free_device(struct ieee802154_dev *dev)
+
+Freeing allocated device.
+
+.. c:function:: int ieee802154_register_device(struct ieee802154_dev *dev)
+
+Register PHY in the system.
+
+.. c:function:: void ieee802154_unregister_device(struct ieee802154_dev *dev)
+
+Freeing registered PHY.
+
+.. c:function:: void ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi):
+
+Telling 802.15.4 module there is a new received frame in the skb with
+the RF Link Quality Indicator (LQI) from the hardware device.
+
+.. c:function:: void ieee802154_xmit_complete(struct ieee802154_hw *hw, struct sk_buff *skb, bool ifs_handling):
+
+Telling 802.15.4 module the frame in the skb is or going to be
+transmitted through the hardware device
+
+The device driver must implement the following callbacks in the IEEE 802.15.4
+operations structure at least::
+
+   struct ieee802154_ops {
+        ...
+        int     (*start)(struct ieee802154_hw *hw);
+        void    (*stop)(struct ieee802154_hw *hw);
+        ...
+        int     (*xmit_async)(struct ieee802154_hw *hw, struct sk_buff *skb);
+        int     (*ed)(struct ieee802154_hw *hw, u8 *level);
+        int     (*set_channel)(struct ieee802154_hw *hw, u8 page, u8 channel);
+        ...
+   };
+
+.. c:function:: int start(struct ieee802154_hw *hw):
+
+Handler that 802.15.4 module calls for the hardware device initialization.
+
+.. c:function:: void stop(struct ieee802154_hw *hw):
+
+Handler that 802.15.4 module calls for the hardware device cleanup.
+
+.. c:function:: int xmit_async(struct ieee802154_hw *hw, struct sk_buff *skb):
+
+Handler that 802.15.4 module calls for each frame in the skb going to be
+transmitted through the hardware device.
+
+.. c:function:: int ed(struct ieee802154_hw *hw, u8 *level):
+
+Handler that 802.15.4 module calls for Energy Detection from the hardware
+device.
+
+.. c:function:: int set_channel(struct ieee802154_hw *hw, u8 page, u8 channel):
+
+Set radio for listening on specific channel of the hardware device.
+
+Moreover IEEE 802.15.4 device operations structure should be filled.
diff --git a/Documentation/networking/index.rst b/Documentation/networking/index.rst
index b08cf145d5eb..f0da1b001514 100644
--- a/Documentation/networking/index.rst
+++ b/Documentation/networking/index.rst
@@ -25,6 +25,7 @@ Contents:
    device_drivers/intel/iavf
    device_drivers/intel/ice
    devlink-info-versions
+   ieee802154
    kapi
    z8530book
    msg_zerocopy
-- 
2.17.2

Re: [PATCH 1/2] doc: net: ieee802154: introduce IEEE 802.15.4 subsystem doc in rst style

[Randy Dunlap]

On 2/27/19 11:59 AM, Stefan Schmidt wrote:
> Moving the ieee802154 docs from a plain text file into the new rst
> style. This commit only does the minimal needed change to bring the
> documentation over. Follow up patches will improve and extend on this.
> 
> Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
> ---
>  Documentation/networking/ieee802154.rst | 180 ++++++++++++++++++++++++
>  Documentation/networking/index.rst      |   1 +
>  2 files changed, 181 insertions(+)
>  create mode 100644 Documentation/networking/ieee802154.rst

Tested-by: Randy Dunlap <rdunlap@infradead.org>

Thanks.

-- 
~Randy

[PATCH 2/2] doc: net: ieee802154: remove old plain text docs after switching to rst

[Stefan Schmidt]

The plain text docs are converted to rst now, which allows us to remove
the old text file from the tree.

Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
---
 Documentation/networking/ieee802154.txt | 177 ------------------------
 1 file changed, 177 deletions(-)
 delete mode 100644 Documentation/networking/ieee802154.txt

diff --git a/Documentation/networking/ieee802154.txt b/Documentation/networking/ieee802154.txt
deleted file mode 100644
index e74d8e1da0e2..000000000000
--- a/Documentation/networking/ieee802154.txt
+++ /dev/null
@@ -1,177 +0,0 @@
-
-		Linux IEEE 802.15.4 implementation
-
-
-Introduction
-============
-The IEEE 802.15.4 working group focuses on standardization of the bottom
-two layers: Medium Access Control (MAC) and Physical access (PHY). And there
-are mainly two options available for upper layers:
- - ZigBee - proprietary protocol from the ZigBee Alliance
- - 6LoWPAN - IPv6 networking over low rate personal area networks
-
-The goal of the Linux-wpan is to provide a complete implementation
-of the IEEE 802.15.4 and 6LoWPAN protocols. IEEE 802.15.4 is a stack
-of protocols for organizing Low-Rate Wireless Personal Area Networks.
-
-The stack is composed of three main parts:
- - IEEE 802.15.4 layer;  We have chosen to use plain Berkeley socket API,
-   the generic Linux networking stack to transfer IEEE 802.15.4 data
-   messages and a special protocol over netlink for configuration/management
- - MAC - provides access to shared channel and reliable data delivery
- - PHY - represents device drivers
-
-
-Socket API
-==========
-
-int sd = socket(PF_IEEE802154, SOCK_DGRAM, 0);
-.....
-
-The address family, socket addresses etc. are defined in the
-include/net/af_ieee802154.h header or in the special header
-in the userspace package (see either http://wpan.cakelab.org/ or the
-git tree at https://github.com/linux-wpan/wpan-tools).
-
-
-Kernel side
-=============
-
-Like with WiFi, there are several types of devices implementing IEEE 802.15.4.
-1) 'HardMAC'. The MAC layer is implemented in the device itself, the device
-   exports a management (e.g. MLME) and data API.
-2) 'SoftMAC' or just radio. These types of devices are just radio transceivers
-   possibly with some kinds of acceleration like automatic CRC computation and
-   comparation, automagic ACK handling, address matching, etc.
-
-Those types of devices require different approach to be hooked into Linux kernel.
-
-
-HardMAC
-=======
-
-See the header include/net/ieee802154_netdev.h. You have to implement Linux
-net_device, with .type = ARPHRD_IEEE802154. Data is exchanged with socket family
-code via plain sk_buffs. On skb reception skb->cb must contain additional
-info as described in the struct ieee802154_mac_cb. During packet transmission
-the skb->cb is used to provide additional data to device's header_ops->create
-function. Be aware that this data can be overridden later (when socket code
-submits skb to qdisc), so if you need something from that cb later, you should
-store info in the skb->data on your own.
-
-To hook the MLME interface you have to populate the ml_priv field of your
-net_device with a pointer to struct ieee802154_mlme_ops instance. The fields
-assoc_req, assoc_resp, disassoc_req, start_req, and scan_req are optional.
-All other fields are required.
-
-
-SoftMAC
-=======
-
-The MAC is the middle layer in the IEEE 802.15.4 Linux stack. This moment it
-provides interface for drivers registration and management of slave interfaces.
-
-NOTE: Currently the only monitor device type is supported - it's IEEE 802.15.4
-stack interface for network sniffers (e.g. WireShark).
-
-This layer is going to be extended soon.
-
-See header include/net/mac802154.h and several drivers in
-drivers/net/ieee802154/.
-
-
-Device drivers API
-==================
-
-The include/net/mac802154.h defines following functions:
- - struct ieee802154_hw *
-   ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops):
-   allocation of IEEE 802.15.4 compatible hardware device
-
- - void ieee802154_free_hw(struct ieee802154_hw *hw):
-   freeing allocated hardware device
-
- - int ieee802154_register_hw(struct ieee802154_hw *hw):
-   register PHY which is the allocated hardware device, in the system
-
- - void ieee802154_unregister_hw(struct ieee802154_hw *hw):
-   freeing registered PHY
-
- - void ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb,
-                              u8 lqi):
-   telling 802.15.4 module there is a new received frame in the skb with
-   the RF Link Quality Indicator (LQI) from the hardware device
-
- - void ieee802154_xmit_complete(struct ieee802154_hw *hw, struct sk_buff *skb,
-                                 bool ifs_handling):
-   telling 802.15.4 module the frame in the skb is or going to be
-   transmitted through the hardware device
-
-The device driver must implement the following callbacks in the IEEE 802.15.4
-operations structure at least:
-struct ieee802154_ops {
-	...
-	int	(*start)(struct ieee802154_hw *hw);
-	void	(*stop)(struct ieee802154_hw *hw);
-	...
-	int	(*xmit_async)(struct ieee802154_hw *hw, struct sk_buff *skb);
-	int	(*ed)(struct ieee802154_hw *hw, u8 *level);
-	int	(*set_channel)(struct ieee802154_hw *hw, u8 page, u8 channel);
-	...
-};
-
- - int start(struct ieee802154_hw *hw):
-   handler that 802.15.4 module calls for the hardware device initialization.
-
- - void stop(struct ieee802154_hw *hw):
-   handler that 802.15.4 module calls for the hardware device cleanup.
-
- - int xmit_async(struct ieee802154_hw *hw, struct sk_buff *skb):
-   handler that 802.15.4 module calls for each frame in the skb going to be
-   transmitted through the hardware device.
-
- - int ed(struct ieee802154_hw *hw, u8 *level):
-   handler that 802.15.4 module calls for Energy Detection from the hardware
-   device.
-
- - int set_channel(struct ieee802154_hw *hw, u8 page, u8 channel):
-   set radio for listening on specific channel of the hardware device.
-
-Moreover IEEE 802.15.4 device operations structure should be filled.
-
-Fake drivers
-============
-
-In addition there is a driver available which simulates a real device with
-SoftMAC (fakelb - IEEE 802.15.4 loopback driver) interface. This option
-provides a possibility to test and debug the stack without usage of real hardware.
-
-See sources in drivers/net/ieee802154 folder for more details.
-
-
-6LoWPAN Linux implementation
-============================
-
-The IEEE 802.15.4 standard specifies an MTU of 127 bytes, yielding about 80
-octets of actual MAC payload once security is turned on, on a wireless link
-with a link throughput of 250 kbps or less.  The 6LoWPAN adaptation format
-[RFC4944] was specified to carry IPv6 datagrams over such constrained links,
-taking into account limited bandwidth, memory, or energy resources that are
-expected in applications such as wireless Sensor Networks.  [RFC4944] defines
-a Mesh Addressing header to support sub-IP forwarding, a Fragmentation header
-to support the IPv6 minimum MTU requirement [RFC2460], and stateless header
-compression for IPv6 datagrams (LOWPAN_HC1 and LOWPAN_HC2) to reduce the
-relatively large IPv6 and UDP headers down to (in the best case) several bytes.
-
-In September 2011 the standard update was published - [RFC6282].
-It deprecates HC1 and HC2 compression and defines IPHC encoding format which is
-used in this Linux implementation.
-
-All the code related to 6lowpan you may find in files: net/6lowpan/*
-and net/ieee802154/6lowpan/*
-
-To setup a 6LoWPAN interface you need:
-1. Add IEEE802.15.4 interface and set channel and PAN ID;
-2. Add 6lowpan interface by command like:
-   # ip link add link wpan0 name lowpan0 type lowpan
-3. Bring up 'lowpan0' interface
-- 
2.17.2

Re: [PATCH 0/2] doc: net: ieee802154: move from plain text to rst

[Jonathan Corbet]

On Wed, 27 Feb 2019 20:59:12 +0100
Stefan Schmidt <stefan@datenfreihafen.org> wrote:

> The patches are based on net-next, but they only touch the networking book so I
> would not expect and trouble. From what I have seen they would go through
> Jonathan's tree after being acked by Dave? If you want this patches against a
> different tree let me know.

Usually Dave takes networking documentation patches directly, so that is
what I would expect here.

I took a quick look anyway; seems generally good.  The main comment I
would make is that much of what's there would be better placed as
kerneldoc comments in the code itself that can then be pulled into the
formatted docs.  But that can be a job for another day...

Thanks,

jon

Re: [PATCH 0/2] doc: net: ieee802154: move from plain text to rst

[Stefan Schmidt]

Hello Jon.

On 27.02.19 21:18, Jonathan Corbet wrote:
> On Wed, 27 Feb 2019 20:59:12 +0100
> Stefan Schmidt <stefan@datenfreihafen.org> wrote:
> 
>> The patches are based on net-next, but they only touch the networking book so I
>> would not expect and trouble. From what I have seen they would go through
>> Jonathan's tree after being acked by Dave? If you want this patches against a
>> different tree let me know.
> 
> Usually Dave takes networking documentation patches directly, so that is
> what I would expect here.

OK, so I got that wrong. Works for me. Dave, you want to take them
directly, if nothing else comes up during review, or should I apply them
to my tree and send them with the next pull request?

> I took a quick look anyway; seems generally good.  The main comment I
> would make is that much of what's there would be better placed as
> kerneldoc comments in the code itself that can then be pulled into the
> formatted docs.  But that can be a job for another day...

Interesting point. That might be indeed a good idea on some parts of
this sparse doc. Need to check how this is handled in other docs. It
also needs extending scope and context, but again something for a follow
up patchset.

regards
Stefan Schmidt

Re: [PATCH 0/2] doc: net: ieee802154: move from plain text to rst

[David Miller]

From: Stefan Schmidt <stefan@datenfreihafen.org>
Date: Wed, 27 Feb 2019 22:20:58 +0100

> Hello Jon.
> 
> On 27.02.19 21:18, Jonathan Corbet wrote:
>> On Wed, 27 Feb 2019 20:59:12 +0100
>> Stefan Schmidt <stefan@datenfreihafen.org> wrote:
>> 
>>> The patches are based on net-next, but they only touch the networking book so I
>>> would not expect and trouble. From what I have seen they would go through
>>> Jonathan's tree after being acked by Dave? If you want this patches against a
>>> different tree let me know.
>> 
>> Usually Dave takes networking documentation patches directly, so that is
>> what I would expect here.
> 
> OK, so I got that wrong. Works for me. Dave, you want to take them
> directly, if nothing else comes up during review, or should I apply them
> to my tree and send them with the next pull request?

I'll take them, thanks.

Re: [PATCH 0/2] doc: net: ieee802154: move from plain text to rst

[David Miller]

From: Stefan Schmidt <stefan@datenfreihafen.org>
Date: Wed, 27 Feb 2019 20:59:12 +0100

> The ieee802154 subsystem doc was still in plain text. With the networking book
> taking shape I thought it was time to do the first step and move it over to rst.
> This really is only the minimal conversion. I need to take some time to update
> and extend the docs.
> 
> The patches are based on net-next, but they only touch the networking book so I
> would not expect and trouble. From what I have seen they would go through
> Jonathan's tree after being acked by Dave? If you want this patches against a
> different tree let me know.

Series applied, thanks Stefan.