Merge tag 'media/v5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

Pull media updates from Mauro Carvalho Chehab:

 - Media documentation is now split into admin-guide, driver-api and
   userspace-api books (a longstanding request from Jon);

 - The media Kconfig was reorganized, in order to make easier to select
   drivers and their dependencies;

 - The testing drivers now has a separate directory;

 - added a new driver for Rockchip Video Decoder IP;

 - The atomisp staging driver was resurrected. It is meant to work with
   4 generations of cameras on Atom-based laptops, tablets and cell
   phones. So, it seems worth investing time to cleanup this driver and
   making it in good shape.

 - Added some V4L2 core ancillary routines to help with h264 codecs;

 - Added an ov2740 image sensor driver;

 - The si2157 gained support for Analog TV, which, in turn, added
   support for some cx231xx and cx23885 boards to also support analog
   standards;

 - Added some V4L2 controls (V4L2_CID_CAMERA_ORIENTATION and
   V4L2_CID_CAMERA_SENSOR_ROTATION) to help identifying where the camera
   is located at the device;

 - VIDIOC_ENUM_FMT was extended to support MC-centric devices;

 - Lots of drivers improvements and cleanups.

* tag 'media/v5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (503 commits)
  media: Documentation: media: Refer to mbus format documentation from CSI-2 docs
  media: s5k5baf: Replace zero-length array with flexible-array
  media: i2c: imx219: Drop <linux/clk-provider.h> and <linux/clkdev.h>
  media: i2c: Add ov2740 image sensor driver
  media: ov8856: Implement sensor module revision identification
  media: ov8856: Add devicetree support
  media: dt-bindings: ov8856: Document YAML bindings
  media: dvb-usb: Add Cinergy S2 PCIe Dual Port support
  media: dvbdev: Fix tuner->demod media controller link
  media: dt-bindings: phy: phy-rockchip-dphy-rx0: move rockchip dphy rx0 bindings out of staging
  media: staging: dt-bindings: phy-rockchip-dphy-rx0: remove non-used reg property
  media: atomisp: unify the version for isp2401 a0 and b0 versions
  media: atomisp: update TODO with the current data
  media: atomisp: adjust some code at sh_css that could be broken
  media: atomisp: don't produce errs for ignored IRQs
  media: atomisp: print IRQ when debugging
  media: atomisp: isp_mmu: don't use kmem_cache
  media: atomisp: add a notice about possible leak resources
  media: atomisp: disable the dynamic and reserved pools
  media: atomisp: turn on camera before setting it
  ...

1 files changed, 62 insertions, 0 deletions

diff --git a/Documentation/driver-api/media/dtv-common.rst b/Documentation/driver-api/media/dtv-common.rst
new file mode 100644
index 000000000000..f8b2c4dc8170
--- /dev/null
+++ b/Documentation/driver-api/media/dtv-common.rst
@@ -0,0 +1,62 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Digital TV Common functions
+---------------------------
+
+Math functions
+~~~~~~~~~~~~~~
+
+Provide some commonly-used math functions, usually required in order to
+estimate signal strength and signal to noise measurements in dB.
+
+.. kernel-doc:: include/media/dvb_math.h
+
+
+DVB devices
+~~~~~~~~~~~
+
+Those functions are responsible for handling the DVB device nodes.
+
+.. kernel-doc:: include/media/dvbdev.h
+
+Digital TV Ring buffer
+~~~~~~~~~~~~~~~~~~~~~~
+
+Those routines implement ring buffers used to handle digital TV data and
+copy it from/to userspace.
+
+.. note::
+
+  1) For performance reasons read and write routines don't check buffer sizes
+     and/or number of bytes free/available. This has to be done before these
+     routines are called. For example:
+
+   .. code-block:: c
+
+        /* write @buflen: bytes */
+        free = dvb_ringbuffer_free(rbuf);
+        if (free >= buflen)
+                count = dvb_ringbuffer_write(rbuf, buffer, buflen);
+        else
+                /* do something */
+
+        /* read min. 1000, max. @bufsize: bytes */
+        avail = dvb_ringbuffer_avail(rbuf);
+        if (avail >= 1000)
+                count = dvb_ringbuffer_read(rbuf, buffer, min(avail, bufsize));
+        else
+                /* do something */
+
+  2) If there is exactly one reader and one writer, there is no need
+     to lock read or write operations.
+     Two or more readers must be locked against each other.
+     Flushing the buffer counts as a read operation.
+     Resetting the buffer counts as a read and write operation.
+     Two or more writers must be locked against each other.
+
+.. kernel-doc:: include/media/dvb_ringbuffer.h
+
+Digital TV VB2 handler
+~~~~~~~~~~~~~~~~~~~~~~
+
+.. kernel-doc:: include/media/dvb_vb2.h