Zitat von Erwin Authried <[EMAIL PROTECTED]>: > Am Donnerstag, den 21.08.2008, 10:46 +0200 schrieb Hendrik Sattler: >> Hi, >> >> I contact you because you are mentioned in the MAINTAINERS file of >> linux-2.6.26 for the mmc_spi drive and SPI subsystem. >> >> I want to share the bus with other SPI devices. The drivers mentions >> pending updates that would allow that. >> Are those available somewhere? >> >> If not, the changes seem to fairly trivial: change SPI controller >> drivers to allow adding a spi_transfer to an spi_message during the >> complete() callback or add another callback that can do this. > > Hi, > > I have done this in a slightly different, rather simple way. I have > added a new "transfer_end" callback function pointer to the spi_transfer > structure. This function can have three return values: > > <0 ... stop spi message after the transfer > 0 ... continue with next transfer > 1 ... repeat current transfer > > If the transfer_end callback is not required, the function pointer must > be set to NULL. > > I have modified the bitbang driver for this new functionality. In > addition, the mmc_spi driver has been changed to make use of the > callback function. It is necessary to pack all transfers that must be > done without being interrupted into a single message. I have done a lot > of testing with a SD card on a shared bus with a lot of other activity, > and I couldn't see any problems.
I'd imagine something like this but instead of the return code, let it fill/clear spi_message::transfers as it likes during this callback and let the caller check the that after the callback (list_empty()). Nice to know that there are no further pitfalls :) HS ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ spi-devel-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/spi-devel-general
