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Subject: Re: [PATCH v9 3/4] docs: Add documentation for userspace client
 interface
To:     Dan Williams <dcbw@redhat.com>, Jakub Kicinski <kuba@kernel.org>,
        Hemant Kumar <hemantk@codeaurora.org>
Cc:     manivannan.sadhasivam@linaro.org, gregkh@linuxfoundation.org,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
        bbhatt@codeaurora.org, loic.poulain@linaro.org,
        netdev@vger.kernel.org
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From:   Jeffrey Hugo <jhugo@codeaurora.org>
Message-ID: <7934e50d-72bd-f20a-54da-33f29c66c3fa@codeaurora.org>
Date:   Mon, 26 Oct 2020 07:56:33 -0600
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On 10/26/2020 7:46 AM, Dan Williams wrote:
> On Mon, 2020-10-26 at 07:38 -0600, Jeffrey Hugo wrote:
>> On 10/25/2020 3:46 PM, Jakub Kicinski wrote:
>>> On Fri, 23 Oct 2020 16:17:54 -0700 Hemant Kumar wrote:
>>>> +UCI driver enables userspace clients to communicate to external
>>>> MHI devices
>>>> +like modem and WLAN. UCI driver probe creates standard character
>>>> device file
>>>> +nodes for userspace clients to perform open, read, write, poll
>>>> and release file
>>>> +operations.
>>>
>>> What's the user space that talks to this?
>>>
>>
>> Multiple.
>>
>> Each channel has a different purpose.  There it is expected that a
>> different userspace application would be using it.
>>
>> Hemant implemented the loopback channel, which is a simple channel
>> that
>> just sends you back anything you send it.  Typically this is consumed
>> by
>> a test application.
>>
>> Diag is a typical channel to be consumed by userspace.  This is
>> consumed
>> by various applications that talk to the remote device for
>> diagnostic
>> information (logs and such).
> 
> QMI too?
> Dan

Interesting question.  My product doesn't use QMI.  I would expect that 
all QMI runs through Router these days, but I am seeing some QMI 
channels in the downstream source.

Hemant, Do you know what is the usecase for the QMI0/QMI1 channels?

-- 
Jeffrey Hugo
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.