Rework SPI to detach it allowing reuse by several devices

[AdrianSoundy]

Description, Motivation and Context

Changes to split out the SPI device layer to separate files to allow for shared use from multiple internal devices like Display, Spi Ethernet

This code needs to be reviewed before before any other changes are made in case things need to be changed.

The Windows.device.Spi is now common to all devices and moved to /src tree
The device layer has been split into the PAL & HAL files where the HAL only needs to ported to new devices.

PAL - nanoSpi.cpp / .h
HAL - CPU_SPI.cpp / CPU_SPI_decl.h

TI-SimpleLink - Changes done but noticed the SPI is a slave implementation and doesn't have any support for chip select. Not sure if it was working before.

Following nanoframework/Windows.Devices.Spi#77.

Other things to do

Modify the cmake config so you can enable the SPI without including the Windows.device.Spi
So that other devices can enable it.

How Has This Been Tested?

Some testing done with ESP32 but other platform untested, not sure if they even build

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: adriansoundy adriansoundy@gmail.com

[josesimoes]

Going through this!

[josesimoes]

Looks good. But would like to test it. Can you please start the PR to the SPI C# library to be able to do it?

A few questions: why do we need to have the option for the SPI operation to be async or not? Unless there is a good reason for not having it, I believe it should be async. Plus is seems that this mixes with CLR events for long running operations...

[nfbot]

@AdrianSoundy there are issues with the code style on the source files.
A PR was submitted with the code style fixes. Please review and merge the changes. See https://github.com/AdrianSoundy/nf-interpreter/pull/7.

Make sure you are using the project code style. Check the details here.

[nfbot]

@AdrianSoundy there are issues with the code style on the source files.
A PR was submitted with the code style fixes. Please review and merge the changes. See https://github.com/AdrianSoundy/nf-interpreter/pull/8.

Make sure you are using the project code style. Check the details here.

[nfbot]

@AdrianSoundy there are issues with the code style on the source files.
A PR was submitted with the code style fixes. Please review and merge the changes. See https://github.com/AdrianSoundy/nf-interpreter/pull/9.

Make sure you are using the project code style. Check the details here.

[AdrianSoundy]

Think i am there now. Managed code is also committed.
Tested with ESP32 OK
Need to test with other platforms. Will do testing once i get the Discovery board.

I have one issue that i would like your thoughts on.
Sharing the Spi bus with an internal device or 2 internal devices. How do we manage 2 devices accessing the same SPI bus at same time. Its ok for managed code threads as there are lock objects for that.
With Enc28j60 driver it accesses bus in a continuation call. What if we want LCD display and Ethernet on same bus.

[josesimoes]

LGTM

[AdrianSoundy]

Tested with an SPI LCD display on both STM32F769 + ESP32

[nfbot]

@AdrianSoundy there are issues with the code style on the source files.
A PR was submitted with the code style fixes. Please review and merge the changes. See https://github.com/AdrianSoundy/nf-interpreter/pull/10.

Make sure you are using the project code style. Check the details here.

[nfbot]

@AdrianSoundy there are issues with the code style on the source files.
A PR was submitted with the code style fixes. Please review and merge the changes. See https://github.com/AdrianSoundy/nf-interpreter/pull/11.

Make sure you are using the project code style. Check the details here.