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-rw-r--r--Documentation/userspace-api/media/drivers/cx2341x-uapi.rst179
-rw-r--r--Documentation/userspace-api/media/drivers/imx-uapi.rst125
-rw-r--r--Documentation/userspace-api/media/drivers/index.rst39
-rw-r--r--Documentation/userspace-api/media/drivers/max2175.rst64
-rw-r--r--Documentation/userspace-api/media/drivers/meye-uapi.rst53
-rw-r--r--Documentation/userspace-api/media/drivers/omap3isp-uapi.rst208
-rw-r--r--Documentation/userspace-api/media/drivers/uvcvideo.rst257
7 files changed, 925 insertions, 0 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 000000000..8a7977af7
--- /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 000000000..8d47712de
--- /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 000000000..05a82f8c0
--- /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 000000000..35d3c4b41
--- /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 000000000..66b1c142f
--- /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 AlcĂ´ve <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 000000000..5f966a874
--- /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 000000000..e5fd8fad3
--- /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