Hi Shawn,

On Wed, Aug 22 2012, Shawn Guo wrote:

    mmc: sdhci: Always pass clock request value zero to set_clock host op

    To allow the set_clock host op to disable the SDCLK source when not
    needed, always call the host op when the requested clock speed is
    zero.  Do this even if host->clock already equals zero, because
    the SDHCI driver may set that value (without calling the host op)
    to force an update at the next (non-zero-speed) call.

    Signed-off-by: Todd Poynor [off-list ref]
    Acked-by: Adrian Hunter [off-list ref]
    Signed-off-by: Chris Ball [off-list ref]

Reverting the commit will get "controller" mode back to work.

Weird; I wonder how that's related to card detection.

I'm afraid it's ultimately a driver bug -- esdhc should be able to
handle having set_clock called with a value of 0.  It seems to have
a case in esdhc_set_clock() for 0, so I'm surprised it's not working.

What's the symptom of the failure?  Can you debug some more?

Thanks,

- Chris.
-- 
Chris Ball   [off-list ref]   <http://printf.net/>
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