[maemo-developers] 770 mmc hardware question - sdhc bugfix needed for high capacity cards?

[From: Frantisek Dufka]

Hi,

this is question mainly to @nokia.com kernel people familiar with 770 
and N800 MMC code and/or OMAP1 vs OMAP2 power management (like those 
ones who fixed bug http://bugs.maemo.org/show_bug.cgi?id=1204#c120)

Is the MMC_POWER_STANDBY feature implemented in OMAP MMC driver for 
latest N800 2.6.18 kernel relevant to 770 hardware? Does omap1710 lower 
MMC slot power in sleep (when all clocks are off) too so this is needed 
for high capacity cards?

Recently I have backported MMC code from N800 2.6.18 kernel to allow 
SDHC cards to be used in 770 but I don't know whether I should let the 
code which waits for the card before turning off MMC clock in or not.

And while we are are at it, here is second question that bugs me for 
long time. Does 770 hardware allow to give MMCmobile cards 1.8 volts? 
 From the schematics floating on the net it looks like OMAP uses 1.8 
volts but there is LP3928TLX voltage converter [1] [2] between omap and 
mmc slot which cannot be bypassed in software, is this correct or did I 
miss something?

And third bonus question, is it stupid idea to search for OMAP pins for 
second MMC interface and connect them directly to dual voltage MMCmobile 
card capable of running at 1.8 volts and have some chance for this to 
actually work?

Frantisek

1. http://www.national.com/opf/LP/LP3928.html
2. http://www.alldatasheet.com/view.jsp?Searchword=LP3928TLX