Implement MCAN shutdown by writing to CSR #45

Ironedde · 2024-02-21T12:41:32Z

MCAN can safely be shut down by writing to the CCCR.CSR register
(Clock Stop Request) and then waiting for CCCR.CSA (Clock Stop
Acknowledge) to become high.

This will not interrupt any ongoing transmissions/receptions and is
therefore deemed the safe way to shut down the bus.

Note: It is not stated directly, but testing has shown that issuing a
stop request will only wait for the currently ongoing transmissions
and not what is queued. These messages will be sent once we enter
operational mode again.

Thank you!

Thank you for your contribution.
Please make sure that your submission includes the following:

Must

The code compiles without errors or warnings.
All tests pass and in the best case you also added new tests.
cargo +stable fmt was run.
cargo +stable clippy yields no warnings.
Your changes were added to the CHANGELOG.md in the proper section.
You add a description of your work to this PR.
You added proper docs (in code, rustdoc and README.md) for your
newly added features and code.

mcan/src/bus.rs

mcan/src/reg.rs

mcan/src/bus.rs

epontan · 2024-02-21T17:47:04Z

Looks great @Ironedde! Just some nits about the documentation and terminology, but otherwise it looks good to me.

vcrn

Looks good! Agree with all comments from @epontan, like changing the name of "shutdown" to "power down mode", or possibly "sleep mode", to be consistent with the official documentation.

I'll try to come up with some suggestion for a high level description for ready_for_shutdown.

vcrn

Looks good to me!

epontan

Looks great, @Ironedde! Just a few remaining nits, otherwise LGTM 👍

mcan/src/bus.rs

mcan/src/reg.rs

mcan/CHANGELOG.md

epontan · 2024-02-23T15:35:21Z

We should perhaps create a commit before this which allows missing_safety_doc in the reg module so the clippy action passes?

Ironedde · 2024-02-23T15:41:11Z

We should perhaps create a commit before this which allows missing_safety_doc in the reg module so the clippy action passes?

@epontan I totally agree, I'm on it.

I also found out why we haven't gotten any annotations on the code when clippy failed.
Acording to the README in the actions-rs/clippy-check repo (which is archived btw), you cannot have a fork with the same name as the original repo and have it work out.

I'll rename my fork after this PR chain.

MCAN can safely be shut down by writing to the `CCCR.CSR` register (Clock Stop Request) and then waiting for `CCCR.CSA` (Clock Stop Acknowledge) to become high. This will not interrupt any ongoing transmissions/receptions and is therefore deemed the safe way to shut down the bus. Note: It is not stated directly, but testing has shown that issuing a stop request will only wait for the currently ongoing transmissions and not what is queued. These messages will be sent once we enter operational mode again.

Ironedde · 2024-03-04T13:12:20Z

@epontan Sorry For all the notifications, I didn't see that you had resolved all the conversations above.

I have now rebased on top of #46 and all checks are going through 😄

epontan

Nice! LGTM 👍

- Add safe way to shutdown the bus when actively transmitting/receiving (GrepitAB#45) - Add method to finalize configuration into initialization mode (GrepitAB#47) - *Breaking* Update the register mappings with svd2rust 0.30.2 and form 0.10.0 (GrepitAB#46)

### Added - Add safe way to shutdown the bus when actively transmitting/receiving (#45) - Add method to finalize configuration into initialization mode (#47) ### Changed - *Breaking* Update the register mappings with svd2rust 0.30.2 and form 0.10.0 (#46)

Ironedde requested a review from a team as a code owner February 21, 2024 12:41

Ironedde force-pushed the implement-shutdown branch from 67a7cd1 to 5cd247c Compare February 21, 2024 12:59