media: docs: add an uAPI chapter for driver-specific stuff

There are some uAPI stuff that are driver-specific. Add them
to the main media uAPI body.

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

11 files changed, 930 insertions, 3 deletions

diff --git a/Documentation/userspace-api/media/drivers/cx2341x-uapi.rst b/Documentation/userspace-api/media/drivers/cx2341x-uapi.rst
new file mode 100644
index 000000000000..8a7977af79d5
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/cx2341x-uapi.rst
@@ -0,0 +1,179 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+The cx2341x driver
+==================
+
+Non-compressed file format
+--------------------------
+
+The cx23416 can produce (and the cx23415 can also read) raw YUV output. The
+format of a YUV frame is specific to this chip and is called HM12. 'HM' stands
+for 'Hauppauge Macroblock', which is a misnomer as 'Conexant Macroblock' would
+be more accurate.
+
+The format is YUV 4:2:0 which uses 1 Y byte per pixel and 1 U and V byte per
+four pixels.
+
+The data is encoded as two macroblock planes, the first containing the Y
+values, the second containing UV macroblocks.
+
+The Y plane is divided into blocks of 16x16 pixels from left to right
+and from top to bottom. Each block is transmitted in turn, line-by-line.
+
+So the first 16 bytes are the first line of the top-left block, the
+second 16 bytes are the second line of the top-left block, etc. After
+transmitting this block the first line of the block on the right to the
+first block is transmitted, etc.
+
+The UV plane is divided into blocks of 16x8 UV values going from left
+to right, top to bottom. Each block is transmitted in turn, line-by-line.
+
+So the first 16 bytes are the first line of the top-left block and
+contain 8 UV value pairs (16 bytes in total). The second 16 bytes are the
+second line of 8 UV pairs of the top-left block, etc. After transmitting
+this block the first line of the block on the right to the first block is
+transmitted, etc.
+
+The code below is given as an example on how to convert HM12 to separate
+Y, U and V planes. This code assumes frames of 720x576 (PAL) pixels.
+
+The width of a frame is always 720 pixels, regardless of the actual specified
+width.
+
+If the height is not a multiple of 32 lines, then the captured video is
+missing macroblocks at the end and is unusable. So the height must be a
+multiple of 32.
+
+Raw format c example
+~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
+	#include <stdio.h>
+	#include <stdlib.h>
+	#include <string.h>
+
+	static unsigned char frame[576*720*3/2];
+	static unsigned char framey[576*720];
+	static unsigned char frameu[576*720 / 4];
+	static unsigned char framev[576*720 / 4];
+
+	static void de_macro_y(unsigned char* dst, unsigned char *src, int dstride, int w, int h)
+	{
+	unsigned int y, x, i;
+
+	// descramble Y plane
+	// dstride = 720 = w
+	// The Y plane is divided into blocks of 16x16 pixels
+	// Each block in transmitted in turn, line-by-line.
+	for (y = 0; y < h; y += 16) {
+		for (x = 0; x < w; x += 16) {
+		for (i = 0; i < 16; i++) {
+			memcpy(dst + x + (y + i) * dstride, src, 16);
+			src += 16;
+		}
+		}
+	}
+	}
+
+	static void de_macro_uv(unsigned char *dstu, unsigned char *dstv, unsigned char *src, int dstride, int w, int h)
+	{
+	unsigned int y, x, i;
+
+	// descramble U/V plane
+	// dstride = 720 / 2 = w
+	// The U/V values are interlaced (UVUV...).
+	// Again, the UV plane is divided into blocks of 16x16 UV values.
+	// Each block in transmitted in turn, line-by-line.
+	for (y = 0; y < h; y += 16) {
+		for (x = 0; x < w; x += 8) {
+		for (i = 0; i < 16; i++) {
+			int idx = x + (y + i) * dstride;
+
+			dstu[idx+0] = src[0];  dstv[idx+0] = src[1];
+			dstu[idx+1] = src[2];  dstv[idx+1] = src[3];
+			dstu[idx+2] = src[4];  dstv[idx+2] = src[5];
+			dstu[idx+3] = src[6];  dstv[idx+3] = src[7];
+			dstu[idx+4] = src[8];  dstv[idx+4] = src[9];
+			dstu[idx+5] = src[10]; dstv[idx+5] = src[11];
+			dstu[idx+6] = src[12]; dstv[idx+6] = src[13];
+			dstu[idx+7] = src[14]; dstv[idx+7] = src[15];
+			src += 16;
+		}
+		}
+	}
+	}
+
+	/*************************************************************************/
+	int main(int argc, char **argv)
+	{
+	FILE *fin;
+	int i;
+
+	if (argc == 1) fin = stdin;
+	else fin = fopen(argv[1], "r");
+
+	if (fin == NULL) {
+		fprintf(stderr, "cannot open input\n");
+		exit(-1);
+	}
+	while (fread(frame, sizeof(frame), 1, fin) == 1) {
+		de_macro_y(framey, frame, 720, 720, 576);
+		de_macro_uv(frameu, framev, frame + 720 * 576, 720 / 2, 720 / 2, 576 / 2);
+		fwrite(framey, sizeof(framey), 1, stdout);
+		fwrite(framev, sizeof(framev), 1, stdout);
+		fwrite(frameu, sizeof(frameu), 1, stdout);
+	}
+	fclose(fin);
+	return 0;
+	}
+
+
+Format of embedded V4L2_MPEG_STREAM_VBI_FMT_IVTV VBI data
+---------------------------------------------------------
+
+Author: Hans Verkuil <hverkuil@xs4all.nl>
+
+
+This section describes the V4L2_MPEG_STREAM_VBI_FMT_IVTV format of the VBI data
+embedded in an MPEG-2 program stream. This format is in part dictated by some
+hardware limitations of the ivtv driver (the driver for the Conexant cx23415/6
+chips), in particular a maximum size for the VBI data. Anything longer is cut
+off when the MPEG stream is played back through the cx23415.
+
+The advantage of this format is it is very compact and that all VBI data for
+all lines can be stored while still fitting within the maximum allowed size.
+
+The stream ID of the VBI data is 0xBD. The maximum size of the embedded data is
+4 + 43 * 36, which is 4 bytes for a header and 2 * 18 VBI lines with a 1 byte
+header and a 42 bytes payload each. Anything beyond this limit is cut off by
+the cx23415/6 firmware. Besides the data for the VBI lines we also need 36 bits
+for a bitmask determining which lines are captured and 4 bytes for a magic cookie,
+signifying that this data package contains V4L2_MPEG_STREAM_VBI_FMT_IVTV VBI data.
+If all lines are used, then there is no longer room for the bitmask. To solve this
+two different magic numbers were introduced:
+
+'itv0': After this magic number two unsigned longs follow. Bits 0-17 of the first
+unsigned long denote which lines of the first field are captured. Bits 18-31 of
+the first unsigned long and bits 0-3 of the second unsigned long are used for the
+second field.
+
+'ITV0': This magic number assumes all VBI lines are captured, i.e. it implicitly
+implies that the bitmasks are 0xffffffff and 0xf.
+
+After these magic cookies (and the 8 byte bitmask in case of cookie 'itv0') the
+captured VBI lines start:
+
+For each line the least significant 4 bits of the first byte contain the data type.
+Possible values are shown in the table below. The payload is in the following 42
+bytes.
+
+Here is the list of possible data types:
+
+.. code-block:: c
+
+	#define IVTV_SLICED_TYPE_TELETEXT       0x1     // Teletext (uses lines 6-22 for PAL)
+	#define IVTV_SLICED_TYPE_CC             0x4     // Closed Captions (line 21 NTSC)
+	#define IVTV_SLICED_TYPE_WSS            0x5     // Wide Screen Signal (line 23 PAL)
+	#define IVTV_SLICED_TYPE_VPS            0x7     // Video Programming System (PAL) (line 16)
+
diff --git a/Documentation/userspace-api/media/drivers/imx-uapi.rst b/Documentation/userspace-api/media/drivers/imx-uapi.rst
new file mode 100644
index 000000000000..8d47712dea9f
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/imx-uapi.rst
@@ -0,0 +1,125 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+i.MX Video Capture Driver
+=========================
+
+Events
+======
+
+.. _imx_api_ipuX_csiY:
+
+ipuX_csiY
+---------
+
+This subdev can generate the following event when enabling the second
+IDMAC source pad:
+
+- V4L2_EVENT_IMX_FRAME_INTERVAL_ERROR
+
+The user application can subscribe to this event from the ipuX_csiY
+subdev node. This event is generated by the Frame Interval Monitor
+(see below for more on the FIM).
+
+Controls
+========
+
+.. _imx_api_FIM:
+
+Frame Interval Monitor in ipuX_csiY
+-----------------------------------
+
+The adv718x decoders can occasionally send corrupt fields during
+NTSC/PAL signal re-sync (too little or too many video lines). When
+this happens, the IPU triggers a mechanism to re-establish vertical
+sync by adding 1 dummy line every frame, which causes a rolling effect
+from image to image, and can last a long time before a stable image is
+recovered. Or sometimes the mechanism doesn't work at all, causing a
+permanent split image (one frame contains lines from two consecutive
+captured images).
+
+From experiment it was found that during image rolling, the frame
+intervals (elapsed time between two EOF's) drop below the nominal
+value for the current standard, by about one frame time (60 usec),
+and remain at that value until rolling stops.
+
+While the reason for this observation isn't known (the IPU dummy
+line mechanism should show an increase in the intervals by 1 line
+time every frame, not a fixed value), we can use it to detect the
+corrupt fields using a frame interval monitor. If the FIM detects a
+bad frame interval, the ipuX_csiY subdev will send the event
+V4L2_EVENT_IMX_FRAME_INTERVAL_ERROR. Userland can register with
+the FIM event notification on the ipuX_csiY subdev device node.
+Userland can issue a streaming restart when this event is received
+to correct the rolling/split image.
+
+The ipuX_csiY subdev includes custom controls to tweak some dials for
+FIM. If one of these controls is changed during streaming, the FIM will
+be reset and will continue at the new settings.
+
+- V4L2_CID_IMX_FIM_ENABLE
+
+Enable/disable the FIM.
+
+- V4L2_CID_IMX_FIM_NUM
+
+How many frame interval measurements to average before comparing against
+the nominal frame interval reported by the sensor. This can reduce noise
+caused by interrupt latency.
+
+- V4L2_CID_IMX_FIM_TOLERANCE_MIN
+
+If the averaged intervals fall outside nominal by this amount, in
+microseconds, the V4L2_EVENT_IMX_FRAME_INTERVAL_ERROR event is sent.
+
+- V4L2_CID_IMX_FIM_TOLERANCE_MAX
+
+If any intervals are higher than this value, those samples are
+discarded and do not enter into the average. This can be used to
+discard really high interval errors that might be due to interrupt
+latency from high system load.
+
+- V4L2_CID_IMX_FIM_NUM_SKIP
+
+How many frames to skip after a FIM reset or stream restart before
+FIM begins to average intervals.
+
+- V4L2_CID_IMX_FIM_ICAP_CHANNEL / V4L2_CID_IMX_FIM_ICAP_EDGE
+
+These controls will configure an input capture channel as the method
+for measuring frame intervals. This is superior to the default method
+of measuring frame intervals via EOF interrupt, since it is not subject
+to uncertainty errors introduced by interrupt latency.
+
+Input capture requires hardware support. A VSYNC signal must be routed
+to one of the i.MX6 input capture channel pads.
+
+V4L2_CID_IMX_FIM_ICAP_CHANNEL configures which i.MX6 input capture
+channel to use. This must be 0 or 1.
+
+V4L2_CID_IMX_FIM_ICAP_EDGE configures which signal edge will trigger
+input capture events. By default the input capture method is disabled
+with a value of IRQ_TYPE_NONE. Set this control to IRQ_TYPE_EDGE_RISING,
+IRQ_TYPE_EDGE_FALLING, or IRQ_TYPE_EDGE_BOTH to enable input capture,
+triggered on the given signal edge(s).
+
+When input capture is disabled, frame intervals will be measured via
+EOF interrupt.
+
+
+File list
+---------
+
+drivers/staging/media/imx/
+include/media/imx.h
+include/linux/imx-media.h
+
+
+Authors
+-------
+
+- Steve Longerbeam <steve_longerbeam@mentor.com>
+- Philipp Zabel <kernel@pengutronix.de>
+- Russell King <linux@armlinux.org.uk>
+
+Copyright (C) 2012-2017 Mentor Graphics Inc.
diff --git a/Documentation/userspace-api/media/drivers/index.rst b/Documentation/userspace-api/media/drivers/index.rst
new file mode 100644
index 000000000000..05a82f8c0c99
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/index.rst
@@ -0,0 +1,39 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: <isonum.txt>
+
+.. _v4l-drivers_uapi:
+
+################################################
+Video4Linux (V4L)  driver-specific documentation
+################################################
+
+**Copyright** |copy| 1999-2016 : LinuxTV Developers
+
+This documentation is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the Free
+Software Foundation version 2 of the License.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+more details.
+
+For more details see the file COPYING in the source distribution of Linux.
+
+.. only:: html
+
+   .. class:: toc-title
+
+        Table of Contents
+
+.. toctree::
+	:maxdepth: 5
+	:numbered:
+
+	cx2341x-uapi
+	imx-uapi
+	max2175
+	meye-uapi
+	omap3isp-uapi
+	uvcvideo
diff --git a/Documentation/userspace-api/media/drivers/max2175.rst b/Documentation/userspace-api/media/drivers/max2175.rst
new file mode 100644
index 000000000000..35d3c4b41fc7
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/max2175.rst
@@ -0,0 +1,64 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Maxim Integrated MAX2175 RF to bits tuner driver
+================================================
+
+The MAX2175 driver implements the following driver-specific controls:
+
+``V4L2_CID_MAX2175_I2S_ENABLE``
+-------------------------------
+    Enable/Disable I2S output of the tuner. This is a private control
+    that can be accessed only using the subdev interface.
+    Refer to Documentation/driver-api/media/v4l2-controls.rst for more details.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``(0)``
+      - I2S output is disabled.
+    * - ``(1)``
+      - I2S output is enabled.
+
+``V4L2_CID_MAX2175_HSLS``
+-------------------------
+    The high-side/low-side (HSLS) control of the tuner for a given band.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``(0)``
+      - The LO frequency position is below the desired frequency.
+    * - ``(1)``
+      - The LO frequency position is above the desired frequency.
+
+``V4L2_CID_MAX2175_RX_MODE (menu)``
+-----------------------------------
+    The Rx mode controls a number of preset parameters of the tuner like
+    sample clock (sck), sampling rate etc. These multiple settings are
+    provided under one single label called Rx mode in the datasheet. The
+    list below shows the supported modes with a brief description.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``"Europe modes"``
+    * - ``"FM 1.2" (0)``
+      - This configures FM band with a sample rate of 0.512 million
+        samples/sec with a 10.24 MHz sck.
+    * - ``"DAB 1.2" (1)``
+      - This configures VHF band with a sample rate of 2.048 million
+        samples/sec with a 32.768 MHz sck.
+
+    * - ``"North America modes"``
+    * - ``"FM 1.0" (0)``
+      - This configures FM band with a sample rate of 0.7441875 million
+        samples/sec with a 14.88375 MHz sck.
+    * - ``"DAB 1.2" (1)``
+      - This configures FM band with a sample rate of 0.372 million
+        samples/sec with a 7.441875 MHz sck.
diff --git a/Documentation/userspace-api/media/drivers/meye-uapi.rst b/Documentation/userspace-api/media/drivers/meye-uapi.rst
new file mode 100644
index 000000000000..66b1c142f920
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/meye-uapi.rst
@@ -0,0 +1,53 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: <isonum.txt>
+
+Vaio Picturebook Motion Eye Camera Driver
+=========================================
+
+Copyright |copy| 2001-2004 Stelian Pop <stelian@popies.net>
+
+Copyright |copy| 2001-2002 Alcôve <www.alcove.com>
+
+Copyright |copy| 2000 Andrew Tridgell <tridge@samba.org>
+
+Private API
+-----------
+
+The driver supports frame grabbing with the video4linux API,
+so all video4linux tools (like xawtv) should work with this driver.
+
+Besides the video4linux interface, the driver has a private interface
+for accessing the Motion Eye extended parameters (camera sharpness,
+agc, video framerate), the snapshot and the MJPEG capture facilities.
+
+This interface consists of several ioctls (prototypes and structures
+can be found in include/linux/meye.h):
+
+MEYEIOC_G_PARAMS and MEYEIOC_S_PARAMS
+	Get and set the extended parameters of the motion eye camera.
+	The user should always query the current parameters with
+	MEYEIOC_G_PARAMS, change what he likes and then issue the
+	MEYEIOC_S_PARAMS call (checking for -EINVAL). The extended
+	parameters are described by the meye_params structure.
+
+
+MEYEIOC_QBUF_CAPT
+	Queue a buffer for capture (the buffers must have been
+	obtained with a VIDIOCGMBUF call and mmap'ed by the
+	application). The argument to MEYEIOC_QBUF_CAPT is the
+	buffer number to queue (or -1 to end capture). The first
+	call to MEYEIOC_QBUF_CAPT starts the streaming capture.
+
+MEYEIOC_SYNC
+	Takes as an argument the buffer number you want to sync.
+	This ioctl blocks until the buffer is filled and ready
+	for the application to use. It returns the buffer size.
+
+MEYEIOC_STILLCAPT and MEYEIOC_STILLJCAPT
+	Takes a snapshot in an uncompressed or compressed jpeg format.
+	This ioctl blocks until the snapshot is done and returns (for
+	jpeg snapshot) the size of the image. The image data is
+	available from the first mmap'ed buffer.
+
+Look at the 'motioneye' application code for an actual example.
diff --git a/Documentation/userspace-api/media/drivers/omap3isp-uapi.rst b/Documentation/userspace-api/media/drivers/omap3isp-uapi.rst
new file mode 100644
index 000000000000..5f966a874a3c
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/omap3isp-uapi.rst
@@ -0,0 +1,208 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: <isonum.txt>
+
+OMAP 3 Image Signal Processor (ISP) driver
+==========================================
+
+Copyright |copy| 2010 Nokia Corporation
+
+Copyright |copy| 2009 Texas Instruments, Inc.
+
+Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
+Sakari Ailus <sakari.ailus@iki.fi>, David Cohen <dacohen@gmail.com>
+
+
+Events
+------
+
+The OMAP 3 ISP driver does support the V4L2 event interface on CCDC and
+statistics (AEWB, AF and histogram) subdevs.
+
+The CCDC subdev produces V4L2_EVENT_FRAME_SYNC type event on HS_VS
+interrupt which is used to signal frame start. Earlier version of this
+driver used V4L2_EVENT_OMAP3ISP_HS_VS for this purpose. The event is
+triggered exactly when the reception of the first line of the frame starts
+in the CCDC module. The event can be subscribed on the CCDC subdev.
+
+(When using parallel interface one must pay account to correct configuration
+of the VS signal polarity. This is automatically correct when using the serial
+receivers.)
+
+Each of the statistics subdevs is able to produce events. An event is
+generated whenever a statistics buffer can be dequeued by a user space
+application using the VIDIOC_OMAP3ISP_STAT_REQ IOCTL. The events available
+are:
+
+- V4L2_EVENT_OMAP3ISP_AEWB
+- V4L2_EVENT_OMAP3ISP_AF
+- V4L2_EVENT_OMAP3ISP_HIST
+
+The type of the event data is struct omap3isp_stat_event_status for these
+ioctls. If there is an error calculating the statistics, there will be an
+event as usual, but no related statistics buffer. In this case
+omap3isp_stat_event_status.buf_err is set to non-zero.
+
+
+Private IOCTLs
+--------------
+
+The OMAP 3 ISP driver supports standard V4L2 IOCTLs and controls where
+possible and practical. Much of the functions provided by the ISP, however,
+does not fall under the standard IOCTLs --- gamma tables and configuration of
+statistics collection are examples of such.
+
+In general, there is a private ioctl for configuring each of the blocks
+containing hardware-dependent functions.
+
+The following private IOCTLs are supported:
+
+- VIDIOC_OMAP3ISP_CCDC_CFG
+- VIDIOC_OMAP3ISP_PRV_CFG
+- VIDIOC_OMAP3ISP_AEWB_CFG
+- VIDIOC_OMAP3ISP_HIST_CFG
+- VIDIOC_OMAP3ISP_AF_CFG
+- VIDIOC_OMAP3ISP_STAT_REQ
+- VIDIOC_OMAP3ISP_STAT_EN
+
+The parameter structures used by these ioctls are described in
+include/linux/omap3isp.h. The detailed functions of the ISP itself related to
+a given ISP block is described in the Technical Reference Manuals (TRMs) ---
+see the end of the document for those.
+
+While it is possible to use the ISP driver without any use of these private
+IOCTLs it is not possible to obtain optimal image quality this way. The AEWB,
+AF and histogram modules cannot be used without configuring them using the
+appropriate private IOCTLs.
+
+
+CCDC and preview block IOCTLs
+-----------------------------
+
+The VIDIOC_OMAP3ISP_CCDC_CFG and VIDIOC_OMAP3ISP_PRV_CFG IOCTLs are used to
+configure, enable and disable functions in the CCDC and preview blocks,
+respectively. Both IOCTLs control several functions in the blocks they
+control. VIDIOC_OMAP3ISP_CCDC_CFG IOCTL accepts a pointer to struct
+omap3isp_ccdc_update_config as its argument. Similarly VIDIOC_OMAP3ISP_PRV_CFG
+accepts a pointer to struct omap3isp_prev_update_config. The definition of
+both structures is available in [#]_.
+
+The update field in the structures tells whether to update the configuration
+for the specific function and the flag tells whether to enable or disable the
+function.
+
+The update and flag bit masks accept the following values. Each separate
+functions in the CCDC and preview blocks is associated with a flag (either
+disable or enable; part of the flag field in the structure) and a pointer to
+configuration data for the function.
+
+Valid values for the update and flag fields are listed here for
+VIDIOC_OMAP3ISP_CCDC_CFG. Values may be or'ed to configure more than one
+function in the same IOCTL call.
+
+- OMAP3ISP_CCDC_ALAW
+- OMAP3ISP_CCDC_LPF
+- OMAP3ISP_CCDC_BLCLAMP
+- OMAP3ISP_CCDC_BCOMP
+- OMAP3ISP_CCDC_FPC
+- OMAP3ISP_CCDC_CULL
+- OMAP3ISP_CCDC_CONFIG_LSC
+- OMAP3ISP_CCDC_TBL_LSC
+
+The corresponding values for the VIDIOC_OMAP3ISP_PRV_CFG are here:
+
+- OMAP3ISP_PREV_LUMAENH
+- OMAP3ISP_PREV_INVALAW
+- OMAP3ISP_PREV_HRZ_MED
+- OMAP3ISP_PREV_CFA
+- OMAP3ISP_PREV_CHROMA_SUPP
+- OMAP3ISP_PREV_WB
+- OMAP3ISP_PREV_BLKADJ
+- OMAP3ISP_PREV_RGB2RGB
+- OMAP3ISP_PREV_COLOR_CONV
+- OMAP3ISP_PREV_YC_LIMIT
+- OMAP3ISP_PREV_DEFECT_COR
+- OMAP3ISP_PREV_GAMMABYPASS
+- OMAP3ISP_PREV_DRK_FRM_CAPTURE
+- OMAP3ISP_PREV_DRK_FRM_SUBTRACT
+- OMAP3ISP_PREV_LENS_SHADING
+- OMAP3ISP_PREV_NF
+- OMAP3ISP_PREV_GAMMA
+
+The associated configuration pointer for the function may not be NULL when
+enabling the function. When disabling a function the configuration pointer is
+ignored.
+
+
+Statistic blocks IOCTLs
+-----------------------
+
+The statistics subdevs do offer more dynamic configuration options than the
+other subdevs. They can be enabled, disable and reconfigured when the pipeline
+is in streaming state.
+
+The statistics blocks always get the input image data from the CCDC (as the
+histogram memory read isn't implemented). The statistics are dequeueable by
+the user from the statistics subdev nodes using private IOCTLs.
+
+The private IOCTLs offered by the AEWB, AF and histogram subdevs are heavily
+reflected by the register level interface offered by the ISP hardware. There
+are aspects that are purely related to the driver implementation and these are
+discussed next.
+
+VIDIOC_OMAP3ISP_STAT_EN
+-----------------------
+
+This private IOCTL enables/disables a statistic module. If this request is
+done before streaming, it will take effect as soon as the pipeline starts to
+stream.  If the pipeline is already streaming, it will take effect as soon as
+the CCDC becomes idle.
+
+VIDIOC_OMAP3ISP_AEWB_CFG, VIDIOC_OMAP3ISP_HIST_CFG and VIDIOC_OMAP3ISP_AF_CFG
+-----------------------------------------------------------------------------
+
+Those IOCTLs are used to configure the modules. They require user applications
+to have an in-depth knowledge of the hardware. Most of the fields explanation
+can be found on OMAP's TRMs. The two following fields common to all the above
+configure private IOCTLs require explanation for better understanding as they
+are not part of the TRM.
+
+omap3isp_[h3a_af/h3a_aewb/hist]\_config.buf_size:
+
+The modules handle their buffers internally. The necessary buffer size for the
+module's data output depends on the requested configuration. Although the
+driver supports reconfiguration while streaming, it does not support a
+reconfiguration which requires bigger buffer size than what is already
+internally allocated if the module is enabled. It will return -EBUSY on this
+case. In order to avoid such condition, either disable/reconfigure/enable the
+module or request the necessary buffer size during the first configuration
+while the module is disabled.
+
+The internal buffer size allocation considers the requested configuration's
+minimum buffer size and the value set on buf_size field. If buf_size field is
+out of [minimum, maximum] buffer size range, it's clamped to fit in there.
+The driver then selects the biggest value. The corrected buf_size value is
+written back to user application.
+
+omap3isp_[h3a_af/h3a_aewb/hist]\_config.config_counter:
+
+As the configuration doesn't take effect synchronously to the request, the
+driver must provide a way to track this information to provide more accurate
+data. After a configuration is requested, the config_counter returned to user
+space application will be an unique value associated to that request. When
+user application receives an event for buffer availability or when a new
+buffer is requested, this config_counter is used to match a buffer data and a
+configuration.
+
+VIDIOC_OMAP3ISP_STAT_REQ
+------------------------
+
+Send to user space the oldest data available in the internal buffer queue and
+discards such buffer afterwards. The field omap3isp_stat_data.frame_number
+matches with the video buffer's field_count.
+
+
+References
+----------
+
+.. [#] include/linux/omap3isp.h
diff --git a/Documentation/userspace-api/media/drivers/uvcvideo.rst b/Documentation/userspace-api/media/drivers/uvcvideo.rst
new file mode 100644
index 000000000000..e5fd8fad333c
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/uvcvideo.rst
@@ -0,0 +1,257 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+The Linux USB Video Class (UVC) driver
+======================================
+
+This file documents some driver-specific aspects of the UVC driver, such as
+driver-specific ioctls and implementation notes.
+
+Questions and remarks can be sent to the Linux UVC development mailing list at
+linux-uvc-devel@lists.berlios.de.
+
+
+Extension Unit (XU) support
+---------------------------
+
+Introduction
+~~~~~~~~~~~~
+
+The UVC specification allows for vendor-specific extensions through extension
+units (XUs). The Linux UVC driver supports extension unit controls (XU controls)
+through two separate mechanisms:
+
+  - through mappings of XU controls to V4L2 controls
+  - through a driver-specific ioctl interface
+
+The first one allows generic V4L2 applications to use XU controls by mapping
+certain XU controls onto V4L2 controls, which then show up during ordinary
+control enumeration.
+
+The second mechanism requires uvcvideo-specific knowledge for the application to
+access XU controls but exposes the entire UVC XU concept to user space for
+maximum flexibility.
+
+Both mechanisms complement each other and are described in more detail below.
+
+
+Control mappings
+~~~~~~~~~~~~~~~~
+
+The UVC driver provides an API for user space applications to define so-called
+control mappings at runtime. These allow for individual XU controls or byte
+ranges thereof to be mapped to new V4L2 controls. Such controls appear and
+function exactly like normal V4L2 controls (i.e. the stock controls, such as
+brightness, contrast, etc.). However, reading or writing of such a V4L2 controls
+triggers a read or write of the associated XU control.
+
+The ioctl used to create these control mappings is called UVCIOC_CTRL_MAP.
+Previous driver versions (before 0.2.0) required another ioctl to be used
+beforehand (UVCIOC_CTRL_ADD) to pass XU control information to the UVC driver.
+This is no longer necessary as newer uvcvideo versions query the information
+directly from the device.
+
+For details on the UVCIOC_CTRL_MAP ioctl please refer to the section titled
+"IOCTL reference" below.
+
+
+3. Driver specific XU control interface
+
+For applications that need to access XU controls directly, e.g. for testing
+purposes, firmware upload, or accessing binary controls, a second mechanism to
+access XU controls is provided in the form of a driver-specific ioctl, namely
+UVCIOC_CTRL_QUERY.
+
+A call to this ioctl allows applications to send queries to the UVC driver that
+directly map to the low-level UVC control requests.
+
+In order to make such a request the UVC unit ID of the control's extension unit
+and the control selector need to be known. This information either needs to be
+hardcoded in the application or queried using other ways such as by parsing the
+UVC descriptor or, if available, using the media controller API to enumerate a
+device's entities.
+
+Unless the control size is already known it is necessary to first make a
+UVC_GET_LEN requests in order to be able to allocate a sufficiently large buffer
+and set the buffer size to the correct value. Similarly, to find out whether
+UVC_GET_CUR or UVC_SET_CUR are valid requests for a given control, a
+UVC_GET_INFO request should be made. The bits 0 (GET supported) and 1 (SET
+supported) of the resulting byte indicate which requests are valid.
+
+With the addition of the UVCIOC_CTRL_QUERY ioctl the UVCIOC_CTRL_GET and
+UVCIOC_CTRL_SET ioctls have become obsolete since their functionality is a
+subset of the former ioctl. For the time being they are still supported but
+application developers are encouraged to use UVCIOC_CTRL_QUERY instead.
+
+For details on the UVCIOC_CTRL_QUERY ioctl please refer to the section titled
+"IOCTL reference" below.
+
+
+Security
+~~~~~~~~
+
+The API doesn't currently provide a fine-grained access control facility. The
+UVCIOC_CTRL_ADD and UVCIOC_CTRL_MAP ioctls require super user permissions.
+
+Suggestions on how to improve this are welcome.
+
+
+Debugging
+~~~~~~~~~
+
+In order to debug problems related to XU controls or controls in general it is
+recommended to enable the UVC_TRACE_CONTROL bit in the module parameter 'trace'.
+This causes extra output to be written into the system log.
+
+
+IOCTL reference
+~~~~~~~~~~~~~~~
+
+UVCIOC_CTRL_MAP - Map a UVC control to a V4L2 control
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Argument: struct uvc_xu_control_mapping
+
+**Description**:
+
+	This ioctl creates a mapping between a UVC control or part of a UVC
+	control and a V4L2 control. Once mappings are defined, userspace
+	applications can access vendor-defined UVC control through the V4L2
+	control API.
+
+	To create a mapping, applications fill the uvc_xu_control_mapping
+	structure with information about an existing UVC control defined with
+	UVCIOC_CTRL_ADD and a new V4L2 control.
+
+	A UVC control can be mapped to several V4L2 controls. For instance,
+	a UVC pan/tilt control could be mapped to separate pan and tilt V4L2
+	controls. The UVC control is divided into non overlapping fields using
+	the 'size' and 'offset' fields and are then independently mapped to
+	V4L2 control.
+
+	For signed integer V4L2 controls the data_type field should be set to
+	UVC_CTRL_DATA_TYPE_SIGNED. Other values are currently ignored.
+
+**Return value**:
+
+	On success 0 is returned. On error -1 is returned and errno is set
+	appropriately.
+
+	ENOMEM
+		Not enough memory to perform the operation.
+	EPERM
+		Insufficient privileges (super user privileges are required).
+	EINVAL
+		No such UVC control.
+	EOVERFLOW
+		The requested offset and size would overflow the UVC control.
+	EEXIST
+		Mapping already exists.
+
+**Data types**:
+
+.. code-block:: none
+
+	* struct uvc_xu_control_mapping
+
+	__u32	id		V4L2 control identifier
+	__u8	name[32]	V4L2 control name
+	__u8	entity[16]	UVC extension unit GUID
+	__u8	selector	UVC control selector
+	__u8	size		V4L2 control size (in bits)
+	__u8	offset		V4L2 control offset (in bits)
+	enum v4l2_ctrl_type
+		v4l2_type	V4L2 control type
+	enum uvc_control_data_type
+		data_type	UVC control data type
+	struct uvc_menu_info
+		*menu_info	Array of menu entries (for menu controls only)
+	__u32	menu_count	Number of menu entries (for menu controls only)
+
+	* struct uvc_menu_info
+
+	__u32	value		Menu entry value used by the device
+	__u8	name[32]	Menu entry name
+
+
+	* enum uvc_control_data_type
+
+	UVC_CTRL_DATA_TYPE_RAW		Raw control (byte array)
+	UVC_CTRL_DATA_TYPE_SIGNED	Signed integer
+	UVC_CTRL_DATA_TYPE_UNSIGNED	Unsigned integer
+	UVC_CTRL_DATA_TYPE_BOOLEAN	Boolean
+	UVC_CTRL_DATA_TYPE_ENUM		Enumeration
+	UVC_CTRL_DATA_TYPE_BITMASK	Bitmask
+
+
+UVCIOC_CTRL_QUERY - Query a UVC XU control
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Argument: struct uvc_xu_control_query
+
+**Description**:
+
+	This ioctl queries a UVC XU control identified by its extension unit ID
+	and control selector.
+
+	There are a number of different queries available that closely
+	correspond to the low-level control requests described in the UVC
+	specification. These requests are:
+
+	UVC_GET_CUR
+		Obtain the current value of the control.
+	UVC_GET_MIN
+		Obtain the minimum value of the control.
+	UVC_GET_MAX
+		Obtain the maximum value of the control.
+	UVC_GET_DEF
+		Obtain the default value of the control.
+	UVC_GET_RES
+		Query the resolution of the control, i.e. the step size of the
+		allowed control values.
+	UVC_GET_LEN
+		Query the size of the control in bytes.
+	UVC_GET_INFO
+		Query the control information bitmap, which indicates whether
+		get/set requests are supported.
+	UVC_SET_CUR
+		Update the value of the control.
+
+	Applications must set the 'size' field to the correct length for the
+	control. Exceptions are the UVC_GET_LEN and UVC_GET_INFO queries, for
+	which the size must be set to 2 and 1, respectively. The 'data' field
+	must point to a valid writable buffer big enough to hold the indicated
+	number of data bytes.
+
+	Data is copied directly from the device without any driver-side
+	processing. Applications are responsible for data buffer formatting,
+	including little-endian/big-endian conversion. This is particularly
+	important for the result of the UVC_GET_LEN requests, which is always
+	returned as a little-endian 16-bit integer by the device.
+
+**Return value**:
+
+	On success 0 is returned. On error -1 is returned and errno is set
+	appropriately.
+
+	ENOENT
+		The device does not support the given control or the specified
+		extension unit could not be found.
+	ENOBUFS
+		The specified buffer size is incorrect (too big or too small).
+	EINVAL
+		An invalid request code was passed.
+	EBADRQC
+		The given request is not supported by the given control.
+	EFAULT
+		The data pointer references an inaccessible memory area.
+
+**Data types**:
+
+.. code-block:: none
+
+	* struct uvc_xu_control_query
+
+	__u8	unit		Extension unit ID
+	__u8	selector	Control selector
+	__u8	query		Request code to send to the device
+	__u16	size		Control data size (in bytes)
+	__u8	*data		Control value
diff --git a/Documentation/userspace-api/media/index.rst b/Documentation/userspace-api/media/index.rst
index 614310f82395..bcfdd1a5caa0 100644
--- a/Documentation/userspace-api/media/index.rst
+++ b/Documentation/userspace-api/media/index.rst
@@ -31,3 +31,5 @@ entitled "GNU Free Documentation License".
     cec/cec-api
     gen-errors
     fdl-appendix
+
+    drivers/index
diff --git a/Documentation/userspace-api/media/v4l/dev-sliced-vbi.rst b/Documentation/userspace-api/media/v4l/dev-sliced-vbi.rst
index 751c6590e774..dd0b6646beb5 100644
--- a/Documentation/userspace-api/media/v4l/dev-sliced-vbi.rst
+++ b/Documentation/userspace-api/media/v4l/dev-sliced-vbi.rst
@@ -438,7 +438,7 @@ MPEG stream.
 *Historical context*: This format specification originates from a
 custom, embedded, sliced VBI data format used by the ``ivtv`` driver.
 This format has already been informally specified in the kernel sources
-in the file ``Documentation/media/v4l-drivers/cx2341x-uapi.rst`` . The
+in the file ``Documentation/userspace-api/media/drivers/cx2341x-uapi.rst`` . The
 maximum size of the payload and other aspects of this format are driven
 by the CX23415 MPEG decoder's capabilities and limitations with respect
 to extracting, decoding, and displaying sliced VBI data embedded within
diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
index f81016c97a0d..9b48338fb783 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
@@ -116,7 +116,7 @@ enum v4l2_mpeg_stream_vbi_fmt -
     * - ``V4L2_MPEG_STREAM_VBI_FMT_IVTV``
       - VBI in private packets, IVTV format (documented in the kernel
 	sources in the file
-	``Documentation/media/v4l-drivers/cx2341x-uapi.rst``)
+	``Documentation/userspace-api/media/drivers/cx2341x-uapi.rst``)
 
 
 
diff --git a/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst b/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst
index dbdcf6c9f072..59b9e7238f90 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst
@@ -58,7 +58,7 @@ please make a proposal on the linux-media mailing list.
       - YUV 4:2:0 format used by the IVTV driver.
 
 	The format is documented in the kernel sources in the file
-	``Documentation/media/v4l-drivers/cx2341x-uapi.rst``
+	``Documentation/userspace-api/media/drivers/cx2341x-uapi.rst``
     * .. _V4L2-PIX-FMT-CPIA1:
 
       - ``V4L2_PIX_FMT_CPIA1``