media: docs: move uAPI book to userspace-api/media

Since 2017, there is an space reserved for userspace API,
created by changeset 1d596dee3862 ("docs: Create a user-space API guide").

As the media subsystem was one of the first subsystems to use
Sphinx, until this patch, we were keeping things on a separate
place.

Let's just use the new location, as having all uAPI altogether
will likely make things easier for developers.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 62 insertions, 0 deletions

diff --git a/Documentation/userspace-api/media/v4l/pixfmt-sdr-pcu20be.rst b/Documentation/userspace-api/media/v4l/pixfmt-sdr-pcu20be.rst
new file mode 100644
index 000000000000..9f3d67b4e94c
--- /dev/null
+++ b/Documentation/userspace-api/media/v4l/pixfmt-sdr-pcu20be.rst
@@ -0,0 +1,62 @@
+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _V4L2-SDR-FMT-PCU20BE:
+
+******************************
+V4L2_SDR_FMT_PCU20BE ('PC20')
+******************************
+
+Planar complex unsigned 20-bit big endian IQ sample
+
+Description
+===========
+
+This format contains a sequence of complex number samples. Each complex
+number consist of two parts called In-phase and Quadrature (IQ). Both I
+and Q are represented as a 20 bit unsigned big endian number stored in
+32 bit space. The remaining unused bits within the 32 bit space will be
+padded with 0. I value starts first and Q value starts at an offset
+equalling half of the buffer size (i.e.) offset = buffersize/2. Out of
+the 20 bits, bit 19:2 (18 bit) is data and bit 1:0 (2 bit) can be any
+value.
+
+**Byte Order.**
+Each cell is one byte.
+
+.. flat-table::
+    :header-rows:  1
+    :stub-columns: 0
+
+    * -  Offset:
+      -  Byte B0
+      -  Byte B1
+      -  Byte B2
+      -  Byte B3
+    * -  start + 0:
+      -  I'\ :sub:`0[19:12]`
+      -  I'\ :sub:`0[11:4]`
+      -  I'\ :sub:`0[3:0]; B2[3:0]=pad`
+      -  pad
+    * -  start + 4:
+      -  I'\ :sub:`1[19:12]`
+      -  I'\ :sub:`1[11:4]`
+      -  I'\ :sub:`1[3:0]; B2[3:0]=pad`
+      -  pad
+    * -  ...
+    * - start + offset:
+      -  Q'\ :sub:`0[19:12]`
+      -  Q'\ :sub:`0[11:4]`
+      -  Q'\ :sub:`0[3:0]; B2[3:0]=pad`
+      -  pad
+    * - start + offset + 4:
+      -  Q'\ :sub:`1[19:12]`
+      -  Q'\ :sub:`1[11:4]`
+      -  Q'\ :sub:`1[3:0]; B2[3:0]=pad`
+      -  pad