This option is apparently also necessary to enable the built-in SD card reader in the Braswell-based Intel Mini PC models NUC5PPYH (4-core Pentium N3700) or NUC5CPYH (2-core Celeron N3050). I enabled two config options since I'm somewhat confused by Intel's platform codenames:
CONFIG_PINCTRL_BAYTRAIL=y CONFIG_PINCTRL_CHERRYVIEW=y Without the changes I get system messages similar to the one below. Note the line which reads "failed to setup card detect gpio": $ dmesg | grep -i SDHCI[ 1.237764] sdhci: Secure Digital Host Controller Interface driver[ 1.237770] sdhci: Copyright(c) Pierre Ossman[ 1.263087] sdhci-pci 0000:00:12.0: SDHCI controller found [8086:2296] (rev 21)[ 1.263442] sdhci-pci 0000:00:12.0: failed to setup card detect gpio[ 1.264537] sdhci-pci 0000:00:12.0: No vmmc regulator found[ 1.264543] sdhci-pci 0000:00:12.0: No vqmmc regulator found[ 1.268300] mmc0: SDHCI controller on PCI [0000:00:12.0] using ADMA
