SD card detection with multiplexed CD/DAT3

[andreygelman]

Is it possible to detect an SD card insertion / removal with a micro-SD socket with multiplexed CD / DAT3 line, in Linux on i.MX6 ?

Thanks !

[max_tsai · Accepted solution]

hi,

CD/DAT3 card detection mechanism is workable on i.MX6, but there is no well-implementation of SDHC bus driver.

You can set uSDHCx_INT_STATUS_EN:CINSSEN, uSDHCx_INT_SIGNAL_EN:CINSIEN, and uSDHCx_PROT_CTRL:D3CD to enable CD/DAT3 card detection mechanism. Before that, you need to configure SD_DAT3 pad with pull-down.

But it's preferred to use mechanism switch(GPIO) for card detection, DAT3 is CS pin for SPI mode. A pull-down on this pin and CMD0 may set this card into the SPI mode.

Regards,

Max