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R-Car boards use GPIO for SD card detection, not use built-in card detection pin, because we have some reasons:

  • Old Renesas SoCs don't have built-in card detection pin.
    • So, for consistency and reliability, we use GPIO for SD card detection on R-Car boards.
  • Using GPIO is an advantage for power management (clock gating and/or power domain) of SDHI modules.
    • If we use built-in card detection pin, we have to turn the SDHI module on anyway.


The TMIO core supports built-in card detection by using the following commits.

c7cd630a9751 mmc: tmio: fix never-detected card insertion bug
497d1f965c20 mmc: tmio: support IP-builtin card detection logic