Merge tag 'media/v6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

Pull media updates from Mauro Carvalho Chehab:

 - New CEC driver: Extron DA HD 4K Plus

 - Lots of driver fixes, cleanups and improvements

* tag 'media/v6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (179 commits)
  media: atomisp: Use clamp() in ia_css_eed1_8_vmem_encode()
  media: atomisp: Fix eed1_8 code assigning signed values to an unsigned variable
  media: atomisp: set lock before calling vb2_queue_init()
  media: atomisp: Improve binary finding debug logging
  media: atomisp: Drop dev_dbg() calls from hmm_[alloc|free]()
  media: atomisp: csi2-bridge: Add DMI quirk for t4ka3 on Xiaomi Mipad2
  media: atomisp: add missing wait_prepare/finish ops
  media: atomisp: Remove unused declaration
  media: atomisp: use clamp() in compute_coring()
  media: atomisp: use clamp() in ia_css_eed1_8_encode()
  media: atomisp: Simplify ia_css_pipe_create_cas_scaler_desc_single_output()
  media: atomisp: Replace rarely used macro from math_support.h
  media: atomisp: Remove duplicated leftover, i.e. sh_css_dvs_info.h
  media: atomisp: bnr: fix trailing statement
  media: atomisp: move trailing */ to separate lines
  media: atomisp: move trailing statement to next line.
  media: atomisp: Fix trailing statement in ia_css_de.host.c
  media: atomisp: Fix spelling mistakes in atomisp.h
  media: atomisp: Fix spelling mistakes in atomisp_platform.h
  media: atomisp: Fix spelling mistake in csi_rx_public.h
  ...

1 files changed, 41 insertions, 26 deletions

diff --git a/Documentation/driver-api/media/mc-core.rst b/Documentation/driver-api/media/mc-core.rst
index 2456950ce8ff..1d010bd7ec49 100644
--- a/Documentation/driver-api/media/mc-core.rst
+++ b/Documentation/driver-api/media/mc-core.rst
@@ -144,7 +144,8 @@ valid values are described at :c:func:`media_create_pad_link()` and
 Graph traversal
 ^^^^^^^^^^^^^^^
 
-The media framework provides APIs to iterate over entities in a graph.
+The media framework provides APIs to traverse media graphs, locating connected
+entities and links.
 
 To iterate over all entities belonging to a media device, drivers can use
 the media_device_for_each_entity macro, defined in
@@ -159,31 +160,6 @@ the media_device_for_each_entity macro, defined in
     ...
     }
 
-Drivers might also need to iterate over all entities in a graph that can be
-reached only through enabled links starting at a given entity. The media
-framework provides a depth-first graph traversal API for that purpose.
-
-.. note::
-
-   Graphs with cycles (whether directed or undirected) are **NOT**
-   supported by the graph traversal API. To prevent infinite loops, the graph
-   traversal code limits the maximum depth to ``MEDIA_ENTITY_ENUM_MAX_DEPTH``,
-   currently defined as 16.
-
-Drivers initiate a graph traversal by calling
-:c:func:`media_graph_walk_start()`
-
-The graph structure, provided by the caller, is initialized to start graph
-traversal at the given entity.
-
-Drivers can then retrieve the next entity by calling
-:c:func:`media_graph_walk_next()`
-
-When the graph traversal is complete the function will return ``NULL``.
-
-Graph traversal can be interrupted at any moment. No cleanup function call
-is required and the graph structure can be freed normally.
-
 Helper functions can be used to find a link between two given pads, or a pad
 connected to another pad through an enabled link
 (:c:func:`media_entity_find_link()`, :c:func:`media_pad_remote_pad_first()`,
@@ -276,6 +252,45 @@ Subsystems should facilitate link validation by providing subsystem specific
 helper functions to provide easy access for commonly needed information, and
 in the end provide a way to use driver-specific callbacks.
 
+Pipeline traversal
+^^^^^^^^^^^^^^^^^^
+
+Once a pipeline has been constructed with :c:func:`media_pipeline_start()`,
+drivers can iterate over entities or pads in the pipeline with the
+:c:macro:´media_pipeline_for_each_entity` and
+:c:macro:´media_pipeline_for_each_pad` macros. Iterating over pads is
+straightforward:
+
+.. code-block:: c
+
+   media_pipeline_pad_iter iter;
+   struct media_pad *pad;
+
+   media_pipeline_for_each_pad(pipe, &iter, pad) {
+       /* 'pad' will point to each pad in turn */
+       ...
+   }
+
+To iterate over entities, the iterator needs to be initialized and cleaned up
+as an additional steps:
+
+.. code-block:: c
+
+   media_pipeline_entity_iter iter;
+   struct media_entity *entity;
+   int ret;
+
+   ret = media_pipeline_entity_iter_init(pipe, &iter);
+   if (ret)
+       ...;
+
+   media_pipeline_for_each_entity(pipe, &iter, entity) {
+       /* 'entity' will point to each entity in turn */
+       ...
+   }
+
+   media_pipeline_entity_iter_cleanup(&iter);
+
 Media Controller Device Allocator API
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^