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- ------------------------------------------------------------------------------
- HACKING
- ------------------------------------------------------------------------------
-
- Coding style
- ------------
-
- The whole library is programmed using the Linux kernel coding style, see
- https://www.kernel.org/doc/html/latest/process/coding-style.html for details.
-
- Please use the same style for any code contributions, thanks!
-
- Amendments to the Linux kernel coding style
- -------------------------------------------
-
- 1) We use the stdint types. The linux kernel accepts the abbreviated types (u8,
- s8, u16 and so on) for legacy reasons. We should in general not introduce
- things like types ourselves as long as they are not necessary to make our
- job possible of refining the hardware and make it easier to be used. stdint
- is a standard and it is not in the scope of our project to introduce a new
- type standard.
-
- 2) Based on the same logic as in (1) we do not use __packed and __aligned
- definitions, it is not our job to add compiler extensions. If we need to
- deal with compiler incompatibility we will do that the same way we are
- dealing with the deprecated attribute by introducing a normal macro that is
- not in the compiler reserved keyword space.
-
- 3) We accept to write an empty body busy waiting while loop like this:
- while (1);
- there is no need to put the colon on the next line as per linux kernel
- style.
-
- 4) We always add brackets around bodies of if, while and for statements, even
- if the body contains only one expression. It is dangerous to not have them
- as it easily happens that one adds a second expression and is hunting for
- hours why the code is not working just because of a missing bracket pair.
-
- Development guidelines
- ----------------------
-
- - Every new file added must have the usual license header, see the
- existing files for examples.
-
- - In general, please try to keep the register and bit naming as close
- as possible to the official vendor datasheets. Among other reasons, this
- makes it easier for users to find what they're looking for in the
- datasheets, programming manuals, and application notes.
-
- - All register definitions should follow the following naming conventions:
-
- - The #define names should be all-caps, parts are separated by
- an underscore.
-
- - The name should be of the form SUBSYSTEM_REGISTER_BIT, e.g.
- ADC_CR2_DMA, where ADC is the subsystem name, CR2 is the register NAME,
- and DMA is the name of the bit in the register that is defined.
-
- - All subsystem-specific function names should be prefixed with the
- subsystem name. For example, gpio_set_mode() or rcc_osc_on().
-
- - Please consistently use the stdint types.
-
- - Variables that are used to store register values read from registers or
- to be stored in a register should be named reg8, reg16, reg32 etc.
-
- - For examples on using libopencm3 see the libopencm3-examples repository.
-
- - Doxygen is used to generate API docs, please follow that style for function
- and definition commentary where possible.
-
- Tips and tricks
- ---------------
-
- SublimeText users:
-
- - The project contains a sublime project description file with some basic
- settings provided to make hacking on libopencm3 easier.
-
- - Recommended SublimeText plugins when hacking on libopencm3:
-
- - TrailingSpaces: Show and trim trailing line spaces.
-
- - SublimeLinter: Run checkpatch.pl in the background while you write your
- code and indicate possible coding style issues on the fly.
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