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    SubjectRe: [PATCH] i2c: tegra: Check for overflow errors with BUG_ON.

    On Mon, Aug 15, 2011 at 12:52:36PM -0700, Doug Anderson wrote:
    > Felipe,
    > On Mon, Aug 15, 2011 at 12:17 PM, Felipe Balbi <> wrote:
    > > so due to a FIFO overflow you lock up the whole system ? Can't you e.g.
    > > reset the controller and reconfigure it rather than locking up the
    > > system ?
    > Certainly we could try to be more proactive and reset / retry / return
    > the error to the client. However, since the only expected situation
    > where this BUG_ON should hit is due to a bug in this driver itself
    > (AKA: i2c clients shouldn't be able to do anything to cause the BUG_ON
    > to hit), that seems like a lot of added complexity.

    so at least just pass an error to the client, but hanging the entire
    system seems a bit too much, dont you think ?

    > Also: if there is an arbitrary software bug that causing an overflow
    > condition to occur, I'm not sure how stable the system will be.
    > Specifically, the i2c controller is used (among other things) to talk
    > to the PMU and adjust voltages in the system. If we just sent it a
    > random command, I'd rather report the bug right away so we don't get
    > hard to find/reproduce failures in other parts of the system.

    that's a good point, I still think that e.g. making a cellphone
    unresponsive until a watchdog reset triggers just because you got a FIFO
    overflow on the I2C controller is too much.

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