doc: reference: promote the canbus subsystem documentation

Promote the Controller Area Network (CAN) subsystem reference
documentation from being part of the networking subsystem documentation
to having its own section.

The networking subsystem primarily deals with IP-based networking,
whereas CAN is a subsystem of its own.

Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>

CODEOWNERS

@@ -183,7 +183,7 @@
 /doc/guides/dts/                          @galak @mbolivar-nordic
 /doc/reference/bluetooth/                 @alwa-nordic @jhedberg @Vudentz
 /doc/reference/devicetree/                @galak @mbolivar-nordic
-/doc/reference/networking/can*            @alexanderwachter
+/doc/reference/canbus/                    @alexanderwachter
 /doc/security/                            @ceolin @d3zd3z
 /drivers/debug/                           @nashif
 /drivers/*/*sam4l*                        @nandojve

MAINTAINERS.yml

@@ -471,7 +471,7 @@ Documentation:
         - samples/drivers/can/
         - tests/drivers/can/
         - samples/subsys/canbus/
-        - doc/reference/networking/can_api.rst
+        - doc/reference/canbus/
         - modules/canopennode/
         - samples/modules/canopennode/
     labels:

doc/reference/canbus/controller.rst

@@ -1,7 +1,7 @@
 .. _can_api:
 
-Controller Area Network (CAN)
-#############################
+CAN Controller API
+##################
 
 .. contents::
     :local:
@@ -39,7 +39,7 @@ This structure is called a wired-AND.
    CAN RX is high, at least for a short time. This is also necessary for
    loopback mode.
 
-.. image:: can_transceiver.svg
+.. image:: transceiver.svg
    :width: 70%
    :align: center
    :alt: CAN Transceiver
@@ -47,7 +47,7 @@ This structure is called a wired-AND.
 
 The bit-timing as defined in ISO 11898-1:2003 looks as following:
 
-.. image:: can_timing.svg
+.. image:: timing.svg
    :width: 40%
    :align: center
    :alt: CAN Timing

doc/reference/canbus/index.rst

@@ -0,0 +1,10 @@
+.. _canbus:
+
+Controller Area Network (CAN)
+#############################
+
+.. toctree::
+   :maxdepth: 2
+
+   controller.rst
+   isotp.rst

doc/reference/canbus/isotp.rst

@@ -36,7 +36,7 @@ The FC also defines the conditions of sending, namely the block-size (BS) and
 the minimum separation time between frames (STmin). The block size defines how
 many CF the sender is allowed to send, before he has to wait for another FC.
 
-.. image:: can_isotp_sequence.svg
+.. image:: isotp_sequence.svg
    :width: 20%
    :align: center
    :alt: ISO-TP Sequence

doc/reference/index.rst

@@ -10,6 +10,7 @@ API Reference
    audio/index.rst
    misc/notify.rst
    bluetooth/index.rst
+   canbus/index.rst
    crypto/index.rst
    devicetree/index.rst
    drivers/index.rst

doc/reference/networking/can.rst

@@ -1,10 +0,0 @@
-.. _net_canbus:
-
-Controller Area Network
-#######################
-
-.. toctree::
-   :maxdepth: 1
-
-   can_api.rst
-   can_isotp.rst

doc/reference/networking/index.rst

@@ -12,5 +12,4 @@ Networking
    protocols.rst
    system_mgmt.rst
    tsn.rst
-   can.rst
    gsm_modem.rst