public inbox for linux-pm@vger.kernel.org
 help / color / mirror / Atom feed
From: Haowen Tu <tuhaowen@uniontech.com>
To: laurent.pinchart@ideasonboard.com
Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
	hansg@kernel.org, mchehab@kernel.org, rafael@kernel.org,
	lenb@kernel.org, pavel@kernel.org, linux-pm@vger.kernel.org,
	linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
	Haowen Tu <tuhaowen@uniontech.com>
Subject: Re: [PATCH 2/2] media: uvcvideo: skip resume when writing hibernation image
Date: Wed, 29 Apr 2026 09:16:11 +0800	[thread overview]
Message-ID: <20260429011611.1936498-1-tuhaowen@uniontech.com> (raw)
In-Reply-To: <20260428091356.GF3219146@killaraus.ideasonboard.com>

Hi Laurent,

On Tue, Apr 28, 2026 at 12:13:56PM +0300, Laurent Pinchart wrote:
> Will all leaf drivers need to implement something similar ? How does
> that scale ?

Thanks, that's a very valid concern.

If this pattern ends up being needed in multiple USB interface drivers,
then handling it in each leaf driver would clearly not scale well.

My initial motivation was that the UVC streaming resume path is reached
from usb_driver.resume(), which doesn't expose the hibernation PM
message. As a result, the driver has no way to distinguish PMSG_THAW
from PMSG_RESTORE locally.

That said, I agree this points to a USB-level design question rather
than just a UVC-specific one. I'll revisit the approach with that in
mind, and will include the USB maintainers and list in the next round.

Thanks,
Haowen

      parent reply	other threads:[~2026-04-29  1:16 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-28  8:05 [PATCH 0/2] PM: hibernate: add helper to detect image-write phase Haowen Tu
2026-04-28  8:05 ` [PATCH 1/2] PM: hibernate: add pm_hibernation_storing_image() helper Haowen Tu
2026-04-28  8:05 ` [PATCH 2/2] media: uvcvideo: skip resume when writing hibernation image Haowen Tu
2026-04-28  8:36   ` Oliver Neukum
2026-04-28  8:58     ` Haowen Tu
2026-04-28  9:13   ` Laurent Pinchart
2026-04-29  1:15     ` Haowen Tu
2026-04-29  1:16     ` Haowen Tu [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260429011611.1936498-1-tuhaowen@uniontech.com \
    --to=tuhaowen@uniontech.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hansg@kernel.org \
    --cc=laurent.pinchart@ideasonboard.com \
    --cc=lenb@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=pavel@kernel.org \
    --cc=rafael@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox