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Subject: Re: [RFC PATCH 0/3] UART slave device bus
From: Marcel Holtmann <marcel@holtmann.org>
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Date: Wed, 24 Aug 2016 10:29:58 -0400
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Hi Alan,

>> So you mean if I do "hciconfig hci0 down", then the uart-bus should
>> "down" the tty and only on "hciconfig hci0 up" it should "up" the
>> tty? I would expect a uart-bus slave-device takes control of the
>> device ("up" it) on probe. It's hardwired anyway.
> 
> Today you can switch stacks at runtime, you can switch between the kernel
> stack and debug tools at runtime. Breaking that is a regression.

actually that is not true. We have HCI User Channel since a long time that gives you raw access to the devices. And also kernel interfaces to do all vendor / debug tasks.

Regards

Marcel