On 09/28/2017 12:23 AM, Mauro Carvalho Chehab wrote: > Add a glossary of terms for V4L2, as several concepts are complex > enough to cause misunderstandings. > > Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> > --- > Documentation/media/uapi/v4l/glossary.rst | 136 ++++++++++++++++++++++++++++++ > Documentation/media/uapi/v4l/v4l2.rst | 1 + > 2 files changed, 137 insertions(+) > create mode 100644 Documentation/media/uapi/v4l/glossary.rst > > diff --git a/Documentation/media/uapi/v4l/glossary.rst b/Documentation/media/uapi/v4l/glossary.rst > new file mode 100644 > index 000000000000..b6767da1a46e > --- /dev/null > +++ b/Documentation/media/uapi/v4l/glossary.rst > @@ -0,0 +1,136 @@ > +======== > +Glossary > +======== > + > +.. note:: > + > + This goal of section is to standardize the terms used within the V4L2 > + documentation. It is written incrementally as they are standardized in > + the V4L2 documentation. So, it is a Work In Progress. > + > +.. Please keep the glossary entries in alphabetical order > + > +.. glossary:: > + > + Bridge driver > + The same as V4L2 main driver. Change this to the more standard phrase: See: V4L2 main driver. > + > + Device Node > + A character device node in the file system used to control and do and -> and/or > + input/output data transfers from/to a Kernel driver. > + > + Digital Signal Processor - DSP > + A specialized microprocessor, with its architecture optimized for > + the operational needs of digital signal processing. I'd say 'requirements' instead of 'needs'. I think that's a better term. > + > + Driver > + The part of the Linux Kernel that implements support > + for a hardware component. > + > + Field-programmable Gate Array - FPGA > + A field-programmable gate array (FPGA) is an integrated circuit > + designed to be configured by a customer or a designer after > + manufacturing. > + > + See https://en.wikipedia.org/wiki/Field-programmable_gate_array. > + > + Hardware component > + A subset of the media hardware. For example an I²C or SPI device, > + or an IP block inside an SoC or FPGA. > + > + Image Signal Processor - ISP > + A specialised processor that implements a set of algorithms for > + processing image data. ISPs may implement algorithms for lens > + shading correction, demosaic, scaling and pixel format conversion > + as well as produce statistics for the use of the control > + algorithms (e.g. automatic exposure, white balance and focus). > + > + Inter-Integrated Circuit - I²C > + A multi-master, multi-slave, packet switched, single-ended, > + serial computer bus used to control V4L2 sub-devices. I'd rephrase this a bit: A multi-master, multi-slave, packet switched, single-ended, serial computer bus. Most V4L2 sub-devices are controlled via this bus. Your text suggested that i2c is used exclusively for V4L2 subdevs, but of course it is used for many other devices as well. > + > + See http://www.nxp.com/docs/en/user-guide/UM10204.pdf. > + > + Integrated circuit - IC > + A set of electronic circuits on one small flat piece of > + semiconductor material, normally silicon. > + > + Also known as chip. Perhaps add an entry for 'Chip' as well, with a 'See: Integrated circuit' as description? Just to be consistent. > + > + Intellectual property core - IP core > + In electronic design a semiconductor intellectual property core, > + is a reusable unit of logic, cell, or integrated circuit layout > + design that is the intellectual property of one party. > + IP cores may be licensed to another party or can be owned > + and used by a single party alone. > + > + See https://en.wikipedia.org/wiki/Semiconductor_intellectual_property_core). > + > + IP block > + The same as IP core. 'See: ' > + > + MC-centric > + V4L2 hardware that requires a Media controller. > + > + See :ref:`v4l2_hardware_control`. > + > + Media Controller > + An API designed to expose and control devices and sub-devices > + relationships to applications. This sentence is not clear. I propose this: An API designed to expose and control the relationships of the Media Harware to applications. > + > + See :ref:`media_controller`. > + > + Media hardware > + A group of hardware components that together make a larger > + user-facing functional media hardware. For instance the SoC ISP IP I'd just say "form the functional". The term 'user-facing' is out of place here. > + cores and external camera sensors together make a make a -> form the Possible synonym for 'form': 'constitute'. I'm OK with either. > + camera media hardware. > + > + Media hardware control > + Type of control for a media hardware supported by V4L2 drivers. > + > + See :ref:`v4l2_hardware_control`. > + > + Microprocessor > + An electronic circuitry that carries out the instructions > + of a computer program by performing the basic arithmetic, logical, > + control and input/output (I/O) operations specified by the > + instructions on a single integrated circuit. > + > + SMBus > + A subset of I²C, with defines a stricter usage of the bus. > + > + Serial Peripheral Interface Bus - SPI > + Synchronous serial communication interface specification used for > + short distance communication, primarily in embedded systems. > + > + System on a Chip - SoC > + An integrated circuit that integrates all components of a computer > + or other electronic systems. > + > + V4L2 device node > + A device node that is associated to a V4L2 main driver, > + as specified in :ref:`v4l2_device_naming`. > + > + V4L2 hardware > + A hardware used to on a media device supported by the V4L2 > + subsystem. No idea what you mean here. Perhaps this: Hardware that is controlled by a V4L2 main driver or a V4L2 sub-device driver. V4L2 hardware is a subset of the Media hardware. Often the two are the same, but Media hardware can also contain other non-V4L2 hardware such as DVB hardware. > + > + V4L2 main driver > + The V4L2 device driver that implements the main logic to talk with > + the V4L2 hardware. > + > + Also known as bridge driver. > + > + See :ref:`v4l2_hardware_control`. > + > + V4L2 sub-device > + Part of the media hardware that is implemented via a > + V4L2 sub-device driver. When we talk about 'V4L2 sub-device' we talk about a driver that implement the subdev kernel API. I suggest that you change 'V4L2 sub-device' to 'V4L2 sub-device driver', then explain that such a driver implements support for a Hardware component. > + > + See :ref:`subdev`. > + > + Vdevnode-centric > + V4L2 hardware that it is controlled via V4L2 device nodes. 'that it' -> 'that' This also needs a reference: See :ref:`v4l2_hardware_control`. > + > + See :ref:`v4l2_hardware_control`. > diff --git a/Documentation/media/uapi/v4l/v4l2.rst b/Documentation/media/uapi/v4l/v4l2.rst > index 2128717299b3..698c060939f0 100644 > --- a/Documentation/media/uapi/v4l/v4l2.rst > +++ b/Documentation/media/uapi/v4l/v4l2.rst > @@ -32,6 +32,7 @@ This part describes the Video for Linux API version 2 (V4L2 API) specification. > videodev > capture-example > v4l2grab-example > + glossary > biblio > > > Regards, Hans
