drivers: display: st: allow-ltdc-callback-override

[markussmST]

Allow overriding the LTDC callback for manual handling or extension In some cases, the default handling may not be desired, for example triggering handling of the next frame/block once the transfer has passed a certain line.

[avolmat-st]

Hi @markussmST,
could you detail a bit more why the current handling of the LTDC handler cannot fit with your usage ?
I am trying to understand if we need to have the whole isr function as a weak or simply allow to call a weak function from within the current isr in order to extend the handling done by the current handler.
The current driver buffer handling is done considering that the isr handler would behave as written within the driver so I am wondering if there is a way to

1. ensuring that the driver will still behave as expected
2. add further handling within the isr handler if necessary

[markussmST]

Hi @markussmST, could you detail a bit more why the current handling of the LTDC handler cannot fit with your usage ? I am trying to understand if we need to have the whole isr function as a weak or simply allow to call a weak function from within the current isr in order to extend the handling done by the current handler. The current driver buffer handling is done considering that the isr handler would behave as written within the driver so I am wondering if there is a way to

1. ensuring that the driver will still behave as expected
2. add further handling within the isr handler if necessary

I was considering that solution as well, with the addition of a return from that function to determine if the existing code should be executed.
One reason for wanting to capture the callback and not execute the buffer swap in my case is that the line interrupt is being set mulitple times per frame to determine the actual active display area in order to maximize the rendering time to include the porches. This could also be used for single buffering to start rendering the next frame up to a certain point once the transfer has passed.

[etienne-lms]

This changes would need stm32_ltdc_global_isr() to be declared in a header file.

[markussmST]

True, I don't know how this ever worked in my testing. I've added a .h file included in the driver.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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