Andy Green wrote: > Does the 2442 peripheral device support recognition of SDIO interrupt > signalling action? Where does that problem begin?
The S3C2442B54 does nominally support SDIO interrupts, yes. The S3C MMC driver doesn't, but there is a patch by Christer Weinigel that adds this functionality. Unfortunately, it only works on some chips of the S3C family, while a few, including ours, act completely erratically. The S3C2442B54 has some glitches that are unique in the S3C family, e.g., the off-by-one issues in SPI. Samsung say that the S3C MMC controller is fine. It gets better, though: Samuel's HIF for the Atheros SDIO stack uses SDIO interrupts but does not exhibit those problems. None of the differences I found between the two drivers seem to explain why they shouldn't behave the same. Maybe it's a silicon malfunction that is affected by supposedly unrelated elements, and we're just unlucky enough to have hit that magic bit or whatever it is. I plan to return to figuring out what's going on there once the more pressing WLAN matters are handled. Sometimes it helps to take a fresh look after a break. By the way, here is some previous discussion of the issues: Subject: Re: PATCH: s3cmci, add card interrupt support on [email protected] and Subject: Re: [PATCH 0/3] RFC: fix bug http://docs.openmoko.org/trac/ticket/1884 on openmoko-kernel. - Werner
