From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpbgsg2.qq.com (smtpbgsg2.qq.com [54.254.200.128]) (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 49EB6140E5F; Wed, 29 Apr 2026 01:16:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.254.200.128 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777425401; cv=none; b=GeFGB4A/+jxcMDZlUXWssMBELAgiGmRBQcO533EDogPftAg1Z47pKjaxnnWinZEPT8RvYRWTnNK3H7G8s2gIA1MGZ8Z6ydVUlU4vqkYfTORwZatVYQN217kX9Np8qQSsv4DQTMntieQcdatY9SNUb04OjdhctzPRGLGLUF+UqDY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777425401; c=relaxed/simple; bh=S+FNbfKs3zWzpba+7WwK68JDLp3UZ3kapy9H/lK6Gi4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=c6lWTEa9PoR5kia9kuTlogmFMmI0GcbanXMEqEFu3NcAlkYpakKS4ysmccRdsTwkJirT7Zwd1vduc4Pk7CsJCuoApH/MDltSVCJ9e5xa4WtTVDxWBDUIj0HHmCsVEbazUCLaO3CxzaGKzQ15Lwjk4SBLshf0vKTJJQ1acwuP0to= 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=Zmk/UYoz; arc=none smtp.client-ip=54.254.200.128 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="Zmk/UYoz" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=uniontech.com; s=onoh2408; t=1777425378; bh=S+FNbfKs3zWzpba+7WwK68JDLp3UZ3kapy9H/lK6Gi4=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=Zmk/UYozO08t3ZIZGbxo0FBEr9SumSHwa3msNi966lVTPM8u7GX9hA0A0ClgetQsv 9qd25c90JCacxxVmC7eeC0s+zVPqdoHwc8unOdZmJ76ozAiq2W+I1LoDLvxuIMLFR+ QcTgKC1UCE085ESexo6tPey8sSPufzU4yB9i3BYo= X-QQ-mid: zesmtpip3t1777425373td3ec577c X-QQ-Originating-IP: GDJcawdk+BQ6NHO957GYWgpbBB1B8/YjOfUyxDCvAHA= Received: from localhost.localdomain ( [localhost]) by bizesmtp.qq.com (ESMTP) with id ; Wed, 29 Apr 2026 09:16:11 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 1 X-BIZMAIL-ID: 3897802648851776766 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 09:16:11 +0800 Message-Id: <20260429011611.1936498-1-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-pm@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: MAu4Ycv3XufaUcrR1qWL3rO+X/JSPnUZebdvPDfqXUIOU2fTSt2UAiFq 81ZysyPu3MXfLKiHrPylIT2bl3Iq/vA3FtcsnlxThb7x5MuyrJR1dZQdud0fviS4FtZa8aO N2R6sEV8YdGWQJZ+T7mKny8V8HrIahvuqf8GweODIh3NK48qc+Y4TEV/dkfNCBhDUFIUYYD tcPRk0hxkox4Qu6efc+8RM8UElvCbXeNsS2s5LUr1YEgRDBZXN0aJ7xc6HPUFhQKJgho6T9 S2Sv1sf58pG2cFUb1GV9P9hGLNqqxypNpQyoijMOF9x0Fqel9L7xA7OSIxcEfCh88w6QeO7 3TRYF+4yqlUQc7zcxmQ0Nkof5pTd27Mojj6nNLnvGKizjfUX1OUUXWzPUMZ5IQwS8NohcdI u4RF/got+5nsqRea5YMv5qVJbZL8cwB7HRqBd4lczJonDekW1b0anlGr4dhPLsmNdufhdhT FMNku+z/UlYiaHeToBJe1ypUvht3P3Swahk+JlblvhPLhnmf7DY58psmxhHP0N9Dj9rew8m B/vSgjV9v+SQ419PoqCHWR15VLTx2Zzc4kMfzNt+Axa+vZjakp0cVXX/7Jw8gHwOU7hwrud yNnjoArAGYdZ4o8xcsKAfJDfwZle6nrIOAc2dg9Fl8/Yt0a+fkMykX4kjNt0HTJO//84YIS EKlBRJEdyMVKtuQSZnSt3u9iqMeyHBjZHMQKzAdzadVZrPXpW+p3fIDh2zJSmX8rd37pwUT 0gd74h8Nx3K8wjV2EpAWZFs16mZrVeyLdebYQeyb6Z7wVJbTKjxM5OuDOm8T0q1lV+TOYKZ 1wntoz7KSzl4w5w5TSDb9ERAVD5tw1ayezsHAqmJESTVs77tY9pwdFuOor197sHZsbQUq7q 3p/F+e0ZbfAlMOwtw+bQOcmo5QwardVEwOmOvD0br8UDkvS+X847YAsuVXP+7UBseC08kwp ETBkETFKmR/F7LNyxnqCI45o5JDPB2wqmBxdPcVDZxUKDEuFZ1udOppYUFZZHUp1FaNupiV 4iTlHJ1siXs0Btp7sb7ncc/h49lO0Ist8dTHqiAYUj5N/h47aUR2TbYSIDvmgIV6Ofe6NgH jxlsN5r7OyqpGPkTs6HWASu11XedK2lp7LNIfprjH2H X-QQ-XMRINFO: M/715EihBoGS47X28/vv4NpnfpeBLnr4Qg== 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