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On 06/12/2015 01:31, Mick wrote: |
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> I came across a rather peculiar phenomenon today with my laptop. I realised |
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> that my bluetooth controller was nowhere to be found. I thought running |
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> hciconfig would bring it up, but all it did was to complain that there was no |
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> device found. rfkill would not list it either. |
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> |
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> Modprobing various modules did not produce a device, so searching for answers |
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> I thought of booting into MSWindows. After I enabled the device in MSWindows |
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> I rebooted into Linux and was surprised to see the bluetooth controller was |
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> visible again in lspci. |
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> |
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> How come that switching off the device in one OS, affects the other? :-/ |
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> |
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> What should I do next time to enable bluetooth from within Linux? |
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> |
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> |
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> PS. There's a parallel to this with the same laptop. Some years ago audio |
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> would randomly never come up at boot and no amount of alsactl could wake it |
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> up. A swift reboot into MSWindows would reset audio and all would work fine |
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> in Linux thereafter. Some cursory troubleshooting at the time didn't help me |
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> much. I don't expect that the two issues are related, but thought of |
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> mentioning it just in case. |
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> |
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|
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We've had a few cases of things like this on the list over the years. It |
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always end up probably a Linux driver bug. Here's what seems to happen: |
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|
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The hardware needs to be enabled/shutdown/fiddled or whatever in some |
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magic way that windows knows about but linux doesn't. Booting into |
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Windows applies the magic so when you reboot into Linux it's now in a |
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state Linux can use. |
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|
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Read the kernel docs for your driver, the odds are good you have to |
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apply a driver tweak for your hardware to make it work right. |
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|
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Then do a Google search for your hardware and laptop types, see what the |
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interwebz have to say. |
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-- |
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Alan McKinnon |
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alan.mckinnon@×××××.com |