[lkml]   [2007]   [Mar]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: passing function pointers through platform devices?
    > I'm developing an SPI- bus >MMC/SD block driver translation layer.

    Another one? There's already been significant work in that area. See for

    Which admittedly didn't behave when I just put it onto my test rig,
    but seems nonetheless to be a significant step forward. It's not like
    everyone has hardware that can use such a driver after all!

    > As part of this layer the write protect and card detect lines need to be read.
    > The method for determining the state of these lines will be board specific.

    Example, one usually wants card detect to be an IRQ, to avoid polling...

    > Is it appropriate to pass a function pointer through a platform device
    > (declared in the mach initialization) to implement card_available and
    > write_protect function calls?

    That's how it's done in that patch. The model being what the PXA MMC/SD
    card driver does, since that's the most generic model I found ... handling
    for example systems which need to poll for card detect, as well as ones
    that can use real gpio based IRQs. The mmc_spi driver doesn't need to know
    which kind of platform it's got.

    - Dave

    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2007-03-07 19:47    [W:0.019 / U:39.208 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site