From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpbgsg1.qq.com (smtpbgsg1.qq.com [54.254.200.92]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BF6181482E8 for ; Wed, 29 Apr 2026 01:15:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.254.200.92 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777425356; cv=none; b=Lj6+5G7GWYzT2qYqPRjIw+oFvn+rhZXro29xb8FD1Q7NoW/hYDT5gh+lTm3F+6qCdy1cEs6UuhBq37oYYI3D8KF9dwjuPp1CCDpGKNrvoJ4XwAWGVnN/HSLSEJFzDveWwrV/rnpCztOc09GfPsywujezgf9YioWik6JCUhno9ME= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777425356; c=relaxed/simple; bh=S+FNbfKs3zWzpba+7WwK68JDLp3UZ3kapy9H/lK6Gi4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=YvoSnTQeyzVHyKLMfNQjIkMJcyFDgctnVKyfFKNXmYB6PAaIKKgaQHvXbJFwx58x5iFKmVWoLiiNT6cOL6j0ND81BG8g7U+ZeveaRTKz4N8BRowvVP8C0dH/TCa2+b6MKgGUf3hb8bKXkQTqzazwBhfPoc8dERo03uISIdT0D2c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com; spf=pass smtp.mailfrom=uniontech.com; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b=GRq/aaug; arc=none smtp.client-ip=54.254.200.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=uniontech.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b="GRq/aaug" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=uniontech.com; s=onoh2408; t=1777425350; bh=S+FNbfKs3zWzpba+7WwK68JDLp3UZ3kapy9H/lK6Gi4=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=GRq/aaug5EgpnX7KC3HZtYa4R0c5hic/2TbSLwND73Hpq4E+76yNmPePvyzq0LuOW ZZmtB5ZqzTBMU3VjDLz9uoNhVUkzMuIZQe/OxBBwjdRiqjwR5HuMGKOceYHQVfmzcd hiu2rsLFe7ByWi/VW8eZ9tz0o1LX7Bml82SZctEA= X-QQ-mid: zesmtpip3t1777425346taac8aee5 X-QQ-Originating-IP: jNQDoEUcLVArnC5uGOzW+T+6J0rgvHPUr5JzTWgQ2yg= Received: from localhost.localdomain ( [localhost]) by bizesmtp.qq.com (ESMTP) with id ; Wed, 29 Apr 2026 09:15:43 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 1 X-BIZMAIL-ID: 18189464401092096931 EX-QQ-RecipientCnt: 12 From: Haowen Tu 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 Subject: Re: [PATCH 2/2] media: uvcvideo: skip resume when writing hibernation image Date: Wed, 29 Apr 2026 09:15:42 +0800 Message-Id: <20260429011542.1936211-1-tuhaowen@uniontech.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20260428091356.GF3219146@killaraus.ideasonboard.com> References: <20260428091356.GF3219146@killaraus.ideasonboard.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: zesmtpip:uniontech.com:qybglogicsvrsz:qybglogicsvrsz3b-0 X-QQ-XMAILINFO: Npb+f4q7yCDR66IiiM+frrEC8JnTY9/JAUTclIOnOyGlW7tZzTNMApNf R9HcwgRQoTqvdeN1n7O5hdZXVvgUS/ZDdCdHbYE6cLAVMiMtvHs3LKecHoYo7jrNpGltvzN rD7QMhCz2sHcCdDIBT82pUjAFtigF3T7IGczj1G1gmwOM3XKlbp72X5Pefbnw7qMo7WR5Mx kX5b1KXoE5ItkeOl8Zgxo7gYNBsRjaOOkt0TqgSpNt3bTc8oKX4HUuGbiESdn1ebEhX0Szq OMCEaav4lvEGIX2glCp8P20LmV0i8e4MbT1wmusHS2kQqP4g6ql5Mp0r7ZKXOnWgQqCYBG4 /VD7TEdvWmvGqErDdaZGejlnQiphuHA2iZ698huZc0etLNYh9R1UBLjxspA+EoabYDlI0Mn nW/qnJ9trgv3rf4uLYsv5nkTZCFXTNfH09AUQY4peB4Myt4lo3VmCshPILqgveJct11Yv+q 6HJqTQLYJ0X71hggQuEyL91ADcRpSbWtjLx4PTya/iLfQ5qftds4d5QHYftY1AZEQEQmkmC rk0jQR+lOrQm38SRPGchKOoNAHeZB0lbTkrtBORDAy88aPyT51uuw9sZ0fkIRvbv5g5LyZN 7U9Ybl959SfomwptxTTHBf2c4xm5XB0Dj0PdtDqhIrFnLRJYwBzSFO1SdMF9DXG37qiLL02 X2hlPz/6v1FS2jHpFhgXwcicLD9Fq3pQWJxA00pbh/7DNePt/pBUILtEAq6sXSvDvf0Nqoe IuB0WZHOsbQDAWYseX95yOdpx0saNP1L/OdBvyl2E5k6YGU9JLdw9arSiZRJxr6bByK19YZ 658epNPyaY2NvIjzsfLD63+cZXhVvgwPOnOPqKk7BbltlUdhLc3wNMcKbWrOtzUVPvLVmjC Jz2lGxyHiC8K6SDpJU85xy8hdDPnjcn9VVCQh6vwbIlZOf4xShfWMqeT7e5OlcNqY5U7h5W 8ClSkenRGpmpWbo0XgOvSr61UJgoV0lMSWD6CsEsmKJkxeI+jbZ+xuIN/QhuMWYxXgfhB+m 8NfiaREzrjzQIpp/9kvbCTvAibJ8fyVTZOZcLFaqkoRnRKYQgrPyw/xo4pdJ0= X-QQ-XMRINFO: MPJ6Tf5t3I/ylTmHUqvI8+Wpn+Gzalws3A== X-QQ-RECHKSPAM: 0 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