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    SubjectRe: best way to handle LEDs
    Hi!

    > > > > Except the led code that is being proposed CAN sit on top of a generic
    > > > > GPIO layer.
    > > >
    > > > I also have issues with a generic GPIO layer. As I mentioned in the
    > > > past, there's serious locking issues with any generic abstraction of
    > > > GPIOs.
    > > >
    > > > 1. You want to be able to change GPIO state from interrupts. This
    > > > implies you can not sleep in GPIO state changing functions.
    > > >
    > > > 2. Some GPIOs are implemented on I2C devices. This means that to
    > > > change state, you must sleep.
    > >
    > > Can't you just busywait? Yes, it is ugly in general, but perhaps it
    > > is better than alternatives...
    >
    > Does the i2c layer support busy waiting or are you suggesting something
    > else?

    I'm suggesting that adding busy wait support to i2c is probably good
    idea. GPIOs are on many small machines, and there are machine
    (spitz/akita?) that differ mainly in "where GPIO lines are
    connected". That cries for GPIO layer.
    Pavel
    --
    Thanks, Sharp!
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