Re: SDHCI: Ricoh [1180:e823] unable to mount MMC cards.

From: Chris Ball
Date: Thu Mar 31 2011 - 14:27:43 EST


Hi Manoj,

On Thu, Mar 31 2011, Manoj wrote:
> Card did not mount. New dmesg is attached.

Okay. There's nothing in the log about Ricoh, which probably means that
it bailed out early in the function. You could add a printk to the top
of ricoh_mmc_fixup_rl5c476() if you want to be really sure that the code
there is getting a chance to run.

I think the likely conclusion is that:

(a) The Ricoh controller has a proprietary MMC function that is stealing
MMC cards away from the SDHCI controller even though the SDHCI could
read them if it had a chance to.

(b) We don't know how to turn the MMC controller off, because our old
method for doing so isn't working on this new 0xe823 model.

I'm adding a few people who've touched this code to CC: in case they
have any ideas on working out how to disable the MMC function. If you
have contact with Ricoh directly or through a vendor, please ask them
for the PCI configuration writes needed to disable the MMC function on
this model so that you can read MMC cards with the SD interface instead.

Thanks,

- Chris.
--
Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/>
One Laptop Per Child
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