diff options
Diffstat (limited to 'Documentation/media/v4l-drivers/cafe_ccic.rst')
-rw-r--r-- | Documentation/media/v4l-drivers/cafe_ccic.rst | 62 |
1 files changed, 0 insertions, 62 deletions
diff --git a/Documentation/media/v4l-drivers/cafe_ccic.rst b/Documentation/media/v4l-drivers/cafe_ccic.rst deleted file mode 100644 index ff7fbce1342a..000000000000 --- a/Documentation/media/v4l-drivers/cafe_ccic.rst +++ /dev/null @@ -1,62 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -The cafe_ccic driver -==================== - -Author: Jonathan Corbet <corbet@lwn.net> - -Introduction ------------- - -"cafe_ccic" is a driver for the Marvell 88ALP01 "cafe" CMOS camera -controller. This is the controller found in first-generation OLPC systems, -and this driver was written with support from the OLPC project. - -Current status: the core driver works. It can generate data in YUV422, -RGB565, and RGB444 formats. (Anybody looking at the code will see RGB32 as -well, but that is a debugging aid which will be removed shortly). VGA and -QVGA modes work; CIF is there but the colors remain funky. Only the OV7670 -sensor is known to work with this controller at this time. - -To try it out: either of these commands will work: - -.. code-block:: none - - $ mplayer tv:// -tv driver=v4l2:width=640:height=480 -nosound - $ mplayer tv:// -tv driver=v4l2:width=640:height=480:outfmt=bgr16 -nosound - -The "xawtv" utility also works; gqcam does not, for unknown reasons. - -Load time options ------------------ - -There are a few load-time options, most of which can be changed after -loading via sysfs as well: - - - alloc_bufs_at_load: Normally, the driver will not allocate any DMA - buffers until the time comes to transfer data. If this option is set, - then worst-case-sized buffers will be allocated at module load time. - This option nails down the memory for the life of the module, but - perhaps decreases the chances of an allocation failure later on. - - - dma_buf_size: The size of DMA buffers to allocate. Note that this - option is only consulted for load-time allocation; when buffers are - allocated at run time, they will be sized appropriately for the current - camera settings. - - - n_dma_bufs: The controller can cycle through either two or three DMA - buffers. Normally, the driver tries to use three buffers; on faster - systems, however, it will work well with only two. - - - min_buffers: The minimum number of streaming I/O buffers that the driver - will consent to work with. Default is one, but, on slower systems, - better behavior with mplayer can be achieved by setting to a higher - value (like six). - - - max_buffers: The maximum number of streaming I/O buffers; default is - ten. That number was carefully picked out of a hat and should not be - assumed to actually mean much of anything. - - - flip: If this boolean parameter is set, the sensor will be instructed to - invert the video image. Whether it makes sense is determined by how - your particular camera is mounted. |