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Date:   Thu, 29 Dec 2022 15:20:10 +0100
Message-ID: <87lemqxpet.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Oliver Neukum <oneukum@suse.com>
Cc:     Wesley Cheng <quic_wcheng@quicinc.com>,
        srinivas.kandagatla@linaro.org, mathias.nyman@intel.com,
        perex@perex.cz, broonie@kernel.org, lgirdwood@gmail.com,
        andersson@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        gregkh@linuxfoundation.org, Thinh.Nguyen@synopsys.com,
        bgoswami@quicinc.com, tiwai@suse.com, robh+dt@kernel.org,
        agross@kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-msm@vger.kernel.org, alsa-devel@alsa-project.org,
        devicetree@vger.kernel.org, linux-usb@vger.kernel.org,
        quic_jackp@quicinc.com, quic_plai@quicinc.com
Subject: Re: [RFC PATCH 04/14] sound: usb: card: Introduce USB SND vendor op callbacks
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On Thu, 29 Dec 2022 14:49:21 +0100,
Oliver Neukum wrote:
> 
> 
> 
> On 24.12.22 00:31, Wesley Cheng wrote:
> > Allow for different vendors to be notified on USB SND connect/disconnect
> > seqeunces.  This allows for vendor USB SND modules to properly initialize
> > and populate internal structures with references to the USB SND chip
> > device.
> 
> Hi,
> 
> this raises a design question. If the system is suspending or, worse,
> hibernating, how do you make sure the offloader and the device are
> suspended in the correct order?
> And what happens if you need to go into reset_resume() when resuming?

I guess we'd need to establish a device link when the binding from the
offload driver is done.  Then the PM order will be assured.


Takashi