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Date:   Wed, 30 Nov 2022 15:04:28 +0100
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Subject: Re: [RFC v1] hack: suspend: usb: option: add reset_resume callback
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To:     Martin Kepplinger <martin.kepplinger@puri.sm>, johan@kernel.org,
        gregkh@linuxfoundation.org
Cc:     linux-usb@vger.kernel.org, phone-devel@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20221130121552.1560379-1-martin.kepplinger@puri.sm>
From:   Oliver Neukum <oneukum@suse.com>
In-Reply-To: <20221130121552.1560379-1-martin.kepplinger@puri.sm>
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On 30.11.22 13:15, Martin Kepplinger wrote:
> Currently to be the same as resume(). This will just avoid re-enumeration
> of the modem device on every system resume.
> 
> This exists only because the usb core will re-enumerate *any* device
> whos' driver doesn't have reset_resume() implemented. A call trace:

Hi,

this is deeply problematic. Strictly speaking it introduces a bug.
By implementing reset_resume() you are telling the rest of the system
that all settings have survived the hibernation. That is likely wrong in
your case.

	Regards
		Oliver