docs: release: migration-guide: 3.7: list CAN bus-off recovery changes

List the changes to the CAN bus-off recovery functionality.

Signed-off-by: Henrik Brix Andersen <[email protected]>

doc/releases/migration-guide-3.7.rst

@@ -58,6 +58,24 @@ Controller Area Network (CAN)
   * ``phase-seg1-data``
   * ``phase-seg1-data``
 
+* Support for manual bus-off recovery was reworked:
+
+  * Automatic bus recovery will always be enabled upon driver initialization regardless of Kconfig
+    options. Since CAN controllers are initialized in "stopped" state, no unwanted bus-off recovery
+    will be started at this point.
+  * The Kconfig ``CONFIG_CAN_AUTO_BUS_OFF_RECOVERY`` was renamed (and inverted) to
+    :kconfig:option:`CONFIG_CAN_MANUAL_RECOVERY_MODE`, which is disabled by default. This Kconfig
+    option enables support for the :c:func:`can_recover()` API function and a new manual recovery mode
+    (see the next bullet).
+  * A new CAN controller operational mode :c:macro:`CAN_MODE_MANUAL_RECOVERY` was added. Support for
+    this is only enabled if :kconfig:option:`CONFIG_CAN_MANUAL_RECOVERY_MODE` is enabled. Having
+    this as a mode allows applications to inquire whether the CAN controller supports manual
+    recovery mode via the :c:func:`can_get_capabilities` API function. The application can then
+    either fail initialization or rely on automatic bus-off recovery. Having this as a mode
+    furthermore allows CAN controller drivers not supporting manual recovery mode to fail early in
+    :c:func:`can_set_mode` during application startup instead of failing when :c:func:`can_recover`
+    is called at a later point in time.
+
 Display
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