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Merge branch 'nfc-convert-from-txt-to-rst'

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Robert Schwebel says:

====================
here is v2 of the series converting the NFC documentation from txt to
rst. Thanks to Jonathan and Dave for the input.

Changes since (implicit) v1:

* replace code-block by more compact :: syntax

* really add the rst file to the index
====================

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
This commit is contained in:
Jakub Kicinski 2019-11-23 11:01:13 -08:00
commit 72a2707a87
2 changed files with 37 additions and 34 deletions
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1
Documentation/networking/index.rst
View File

@ -33,6 +33,7 @@ Contents:
scaling
tls
tls-offload
nfc
.. only:: subproject and html

70
Documentation/networking/nfc.txt → Documentation/networking/nfc.rst
View File

@ -1,3 +1,4 @@
===================
Linux NFC subsystem
===================
@ -8,7 +9,7 @@ This document covers the architecture overview, the device driver interface
description and the userspace interface description.
Architecture overview
---------------------
=====================
The NFC subsystem is responsible for:
- NFC adapters management;
@ -25,33 +26,34 @@ The control operations are available to userspace via generic netlink.
The low-level data exchange interface is provided by the new socket family
PF_NFC. The NFC_SOCKPROTO_RAW performs raw communication with NFC targets.
.. code-block:: none
+--------------------------------------+
| USER SPACE |
+--------------------------------------+
^ ^
| low-level | control
| data exchange | operations
| |
| v
| +-----------+
| AF_NFC | netlink |
| socket +-----------+
| raw ^
| |
v v
+---------+ +-----------+
| rawsock | <--------> | core |
+---------+ +-----------+
^
|
v
+-----------+
| driver |
+-----------+
+--------------------------------------+
| USER SPACE |
+--------------------------------------+
^ ^
| low-level | control
| data exchange | operations
| |
| v
| +-----------+
| AF_NFC | netlink |
| socket +-----------+
| raw ^
| |
v v
+---------+ +-----------+
| rawsock | <--------> | core |
+---------+ +-----------+
^
|
v
+-----------+
| driver |
+-----------+
Device Driver Interface
-----------------------
=======================
When registering on the NFC subsystem, the device driver must inform the core
of the set of supported NFC protocols and the set of ops callbacks. The ops
@ -64,7 +66,7 @@ callbacks that must be implemented are the following:
* data_exchange - send data and receive the response (transceive operation)
Userspace interface
--------------------
===================
The userspace interface is divided in control operations and low-level data
exchange operation.
@ -82,7 +84,7 @@ The operations are composed by commands and events, all listed below:
* NFC_EVENT_DEVICE_ADDED - reports an NFC device addition
* NFC_EVENT_DEVICE_REMOVED - reports an NFC device removal
* NFC_EVENT_TARGETS_FOUND - reports START_POLL results when 1 or more targets
are found
are found
The user must call START_POLL to poll for NFC targets, passing the desired NFC
protocols through NFC_ATTR_PROTOCOLS attribute. The device remains in polling
@ -101,14 +103,14 @@ it's closed.
LOW-LEVEL DATA EXCHANGE:
The userspace must use PF_NFC sockets to perform any data communication with
targets. All NFC sockets use AF_NFC:
targets. All NFC sockets use AF_NFC::
struct sockaddr_nfc {
sa_family_t sa_family;
__u32 dev_idx;
__u32 target_idx;
__u32 nfc_protocol;
};
struct sockaddr_nfc {
sa_family_t sa_family;
__u32 dev_idx;
__u32 target_idx;
__u32 nfc_protocol;
};
To establish a connection with one target, the user must create an
NFC_SOCKPROTO_RAW socket and call the 'connect' syscall with the sockaddr_nfc