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