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    SubjectRe: [PATCH] pwm-backlight: add regulator and GPIO support
    On Wed, Jul 04, 2012 at 09:26:58PM +0900, Alex Courbot wrote:
    > On 07/04/2012 07:48 PM, Sascha Hauer wrote:>> +

    > > This looses several resources allocated earlier, like the enable gpio
    > > and the pwm. This is really bad here since I have no regulator specified
    > > and devm_regulator_get returns with -EPROBE_DEFER. Next time the core
    > > tries to probe the driver the driver bails out because the gpio and the
    > > pwm is already requested.

    > That's very bad indeed. I assumed that the kernel would free
    > devm-allocated resources after probe returned -EPROBE_DEFER, so that
    > probe could reallocate them the next time it is called. Apparently
    > that was wrong. Do you know what would the right approach be in this
    > case? Does the kernel preserve the device structure and its
    > associated data between the two calls to probe? If so, I could just
    > check whether the private data has already been constructed to know
    > which state we are in and continue from there.

    I'd really expect the devm_ functions to behave as you expect - if they
    don't currently we should probably fix them so that they do otherwise
    we're going to be in for a lot of surprises and probe deferral becomes a
    lot more cumbersome to use.

     \ /
      Last update: 2012-07-04 15:41    [W:0.027 / U:2.060 seconds]
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