sdhci (4)

Leading comments

Copyright (c) 2008 Alexander Motin <mav@FreeBSD.org>
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. The name of the author may not be used to endorse or promote products
   derived from this software without specific prior written permission.

T...

(The comments found at the beginning of the groff file "man4/sdhci.4freebsd".)

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.conf5:

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

DESCRIPTION

The 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 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

An Alexander Motin Aq 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.