[PATCH 2/2] imx: kontron-sl-mx8mm: Enable PCA9450 regulator driver and fix SD card access

[Fabio Estevam]

On 23/06/2022 14:42, Frieder Schrempf wrote:
> From: Frieder Schrempf <frieder.schrempf at kontron.de>
> 
> Currently accessing the SD card on USDHC2 fails with:
> 
> => mmc dev 1
> Card did not respond to voltage select! : -110
> 
> This is due to the fact that UHS modes are enabled in the defconfig
> and the devicetree, but the referenced LDO5 regulator (reg_nvcc_sd)
> is not available to switch the data lines from 3.3V to 1.8V mode.
> 
> By enabling the regulator driver the vqmmc-supply is now available
> and the SD card works also in high speed modes:
> 
> => mmc dev 1
> switch to partitions #0, OK
> mmc1 is current device
> 
> Please note that the board has a GPIO connected to the SD_VSEL signal
> of the PMIC. As the driver uses the LDO5CTRL_H register to set the
> voltage, we need to make sure that this GPIO (GPIO01_IO4) is set to
> a high level.
> 
> Signed-off-by: Frieder Schrempf <frieder.schrempf at kontron.de>

Reviewed-by: Fabio Estevam <festevam at denx.de>