Ok, to sum this up:

SDIO IRQs are working in mx_sdhci in the Freescale tree because it was
properly implemented and tested, obviously.

Not sure about "properly", but, yes ;)

SDIO IRQs are working for sdhci in mainline probably for other
non-freescale platforms.

Probably, but I can't say 'yes' for sure. You'd need to find out.

You fixed the generic sdhci driver in mainline to work with iMX53 to get
rid of the need for mx_sdhci, but probably never got the chance to test
if SDIO IRQs are really working.

I worked mainly with MX25/35 back then, and a little bit with MX51. IIRC
I only had an SDIO card for which no Linux drivers were available, so I
only could test that the card was detected :(

That means, the subtle difference between mx_sdhci and sdhci to get SDIO
IRQS to work on sdhci with iMX53 has yet to be found.

Yup. Try 'git log --follow sdhci-esdhc-imx.c' to find people who worked
with MX53 or SDIO using that driver.

Regards,

   Wolfram

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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