NAME

     sdhci — PCI SD Host Controller bridge driver

SYNOPSIS

     To compile this driver into the kernel, place the following lines in your kernel
     configuration file:

           device mmc
           device mmcsd
           device sdhci

     Alternatively, to load the driver as a module at boot time, place the following lines in
     loader.conf(5):

           mmc_load="YES"
           mmcsd_load="YES"
           sdhci_load="YES"

DESCRIPTION

     The sdhci driver supports PCI devices with class 8 and subclass 5 according to SD Host
     Controller Specification.  Driver supports up to six high speed 4bit MMC/SD slots per
     controller.  Driver attaches mmc bus to the respective slot on card insertion and detaches
     it on card removing.

HARDWARE

     The sdhci driver supports different specification compatible chips. The following chips have
     been verified to work:

     •   ENE CB712
     •   ENE CB714
     •   RICOH R5C822
     •   RICOH R5CE823
     •   TI PCIXX21/XX11

SEE ALSO

     mmc(4), mmcsd(4)

     SD Specifications, Part 2, SD Host Controller, Simplified Specification.

AUTHORS

     Alexander Motin <mav@FreeBSD.org>.

BUGS

     Many of existing SD controller chips have some nonstandard requirements, proprietary
     registers and hardware bugs, requiring additional handling.  ENE chips are handled to work
     fine, while some revisions of RICOH and TI controllers still do not see cards without some
     additional initialization.