SRU JUSTIFICATION
================

EFFECT
======
Ricoh 1180:e823 does not recognize certain types of SD/MMC cards. 
- Buffalo SD 512MB
  dmesg: I/O error, dev mmcblk0, sector xxx
- Kingston SD 2GB
  dmesg: I/O error, dev mmcblk0, sector xxx
- Patriot Micro SDHC
  dmesg: I/O error, dev mmcblk0, sector xxx.

FIX
===
Lowering the SD base clock frequency from 200Mhz to 50Mhz fixes this issue. 
This solution was suggest by Koji Matsumuro, Ricoh Company, Ltd.

TEST
====
Performance test results with various MMC and SD cards were posted to 
https://lkml.org/lkml/2011/7/11/381 and also part of the results attached to 
this bug.

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https://bugs.launchpad.net/bugs/773524

Title:
  [Toshiba Tecra R850] SD card reader doesn't work

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