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    SubjectRe: Nokia N900 - audio TPA6130A2 problems
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    Hi,

    On 17.03.2016 02:49, Sebastian Reichel wrote:
    >
    > mh both, the power gpio is turned off in tpa6130a2_power(0). I guess
    > if you don't see the problem during probe() everything works?
    >
    > I have another idea though: In opposit to the gpio, the regulator
    > may also be referenced by something else/already enabled. I guess
    > adding a sleep after the regulator_enable() is worth a try.
    >
    > Also I wonder if the same happens, if you avoid having the module
    > available during boot and instead load it once everything has
    > settled. That would rule out any side-effects of other modules
    > being probed on the same i2c bus.


    Well, I think I've figured it out - input pullups are not enabled
    on i2c bus pins, in stock kernel we have:

    ./devmem2 0x480021BC
    Value at address 0x480021BC (0x4001f1bc): 0x1180118

    ./devmem2 0x480021C0
    Value at address 0x480021C0 (0x4001f1c0): 0x1180118

    in mainline

    ./devmem2 0x480021BC
    Value at address 0x480021BC (0xb6ff01bc): 0x1000100

    ./devmem2 0x480021C0
    Value at address 0x480021C0 (0xb6f6d1c0): 0x1000100

    I wonder how i2c devices work at all :)

    Will fix the board DTS file later on an will report

    Regards,
    Ivo

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