drivers: display: stm32_ltdc: mask irq if necessary #90972
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pavlohamov
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checked on stm32f746g, stm32h7b3i. with lvgl:
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@ markussmST FYI |
avolmat-st
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Jun 23, 2025
drivers/display/display_stm32_ltdc.c
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| @@ -223,7 +224,10 @@ static int stm32_ltdc_write(const struct device *dev, const uint16_t x, | |||
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| data->pend_buf = pend_buf; | |||
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| __HAL_LTDC_CLEAR_FLAG(&data->hltdc, LTDC_FLAG_LI); | |||
| irq_enable(config->irqn); | |||
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Rather than turn off the whole interrupt line at the NVIC level, what about simply disabling at the source, hence at the LTDC level.
This could be something like:
__HAL_LTDC_CLEAR_FLAG(&data->hltdc, LTDC_FLAG_LI);
__HAL_LTDC_ENABLE_IT(&data->hltdc, LTDC_IT_LI);
k_sem_take(...)
__HAL_LTDC_DISABLE_IT(&data->hltdc, LTDC_IT_LI);
Avoid calling __HAL_LTDC_ENABLE_IT(&data->hltdc, LTDC_IT_LI); at the ltdc init time is also necessary.
That done, if for some reason others interrupts are still needed it is still possible to handle them and only the LI interrupt is masked.
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Thanks for such a valuable input. Masking just a particular signal looking much more clean - done
@avolmat-st could you be so kind to take another look?
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drivers/display/display_stm32_ltdc.c
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| @@ -479,7 +484,6 @@ static int stm32_ltdc_init(const struct device *dev) | |||
| LTDC->LIPCR = 0U; | |||
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| __HAL_LTDC_CLEAR_FLAG(&data->hltdc, LTDC_FLAG_LI); | |||
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This interrupt flag clear is most probably useless now since anyway interrupts are not enabled.
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Agree, that is making sense. Thanks, done
LTDC interrupt routine is used to reload frame buffer pointer once full frame is finished flushing. As long as there is no need to change buffer - there is no need to disturb CPU. Thus: Enable LTDC interrupt only when new buffer is pending Signed-off-by: Pavlo Hamov <[email protected]>
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LTDC interrupt routine is used to reload frame buffer pointer
once full frame is finished flushing. As long as there is no
need to change buffer - there is no need to disturb CPU.
Thus: Enable LTDC interrupt only when new buffer is pending