From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpbgbr2.qq.com (smtpbgbr2.qq.com [54.207.22.56]) (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 930C1202C5C; Wed, 29 Apr 2026 01:16:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.207.22.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777425381; cv=none; b=MkJorIIuJM/hrfzJM/2o+vxqbEu9fOjAlRGBXxvo8hXch4dU0UOeM2rnGy6GZbaWhx9ldu4yoABoNZYdWad8qdwcmop2ghe9ZR8a5E6qg6Nwm4FoBmgzPFEXFIDnhOWocWLidEC46NbB+iG/8ugLdCTTDtQkpGKLjDMVFmb7w+c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777425381; c=relaxed/simple; bh=S+FNbfKs3zWzpba+7WwK68JDLp3UZ3kapy9H/lK6Gi4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=NCOOYuk5wzN6C7t4/jDHegQM+bXauGDLqIP8NM4Mp0lJT72+6XRvkUDZrbYwpfeAHQ/ua4naW3S8OtmcVpkOaqiEH/A/qWJwhKr0UnjzB8gBKPR3YTxZIs3Uo63Qv20ZkaTMs8aO5DHJxVndqr77MKppcFf76iZRrTowREJpMs8= 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=Qa05oXec; arc=none smtp.client-ip=54.207.22.56 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="Qa05oXec" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=uniontech.com; s=onoh2408; t=1777425351; bh=S+FNbfKs3zWzpba+7WwK68JDLp3UZ3kapy9H/lK6Gi4=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=Qa05oXec8ahYERRQAxUaMixD+mbcDBwzibYzCA114+uzqzPlyK7SaDkf4qaibxHSG xsfHa+jhuaIyG4a5EdLkEJzWeZ1Nhu+t1K2rA06WoKjW+1Oda5idsrkXcKY13Nem3K df0wrlRXnSywkPorvPZZ+6wOi43zlU4Oj+oki+mY= 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-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: OV65e10zTgieZCDzPvCfK5Z3DLP3a2mWak7upSWW93O6bknB3+JlJssY eOJd0K1CMNpGJJbJ+qju+AnF4HE/OqvPvL+Su2LGoUCkQ4v/qt33U68b2xc035L6TM4mf6c MC4/V2uQQiUkgn/Wj2W2IgVa2kGCIaLC/f6BjaZfgyBX3mon/38v8Vo+63T6G7kOaB82jsq Ptw1d/15Jk+jgPPJKj1iCJrAPPeE7E7Wq9klef+x2ESJsi/4T4cXgKz9MqytGjTD7ENYjsy msmUe7MHIEueAmhk3xDUSpGAS+8ePtcfpNeTkLt+675opzFwmcWS7IrDUpkRwfHAuRBo47R QEh0q8g7d7MYixi+gIHDvb3Mcf7rtTdQRmoRlo/hsYSATOkZxQKxg1Fa1O9HyhSRKsbIobG flkoqkDJ7vvKUhYy2EEbA7ndOucKwk4NBcouUd+4H2sJiBVcMTLFArLm9Zglb09qYcCIFsQ KyxTPA8gWKcOwUfcYSekTc9mcSm1OkLUfGQzoUmoqYfi9+Pmeb4RFhXppMj3vJioa8Uk5Jc z2Hai1034SddtBhAJPs8ljPhYV5Gkar6SDq9fTrZDD7x0sqtvm94CKjqLXrBPfl7X0cVQVX c3C0o5wzdFKfrIlDF6eNGEfiqzY/s1/EhwNC2OF2L0OSKPitrbUCNw4lfRNZU82859M6dHL EQYhcBOf001r6KW0BEp9gbhDU3WnK6G2A7nOs5jEAPZ3V3fNHZp16LSeYm2wU76iPoM14nl rjSXab8am76oDM39oQhR70J2e/lSK1hSB1p4qlY8B+N2sIWvBaKMQTBlex4CZScaH1voFtA 5lz1+gCf3ihv9tsfIAX/6M+7givN61j8AG2ERGPTX7hHPtgpt71s/D3gR2hW29dz82Jh0FH n6LpA3ap9pCDAEEuNIm9jp67urRsUbkDDaoDnDZECpPCd5f9NrMeZ85fW5Rfs0fDQDALztx hjR0EqwmZjZuOYv+9dzcJ2+9gJ9YOp0rUSVm627xyVlKfJ3Sd59F9DkU5NrKlWnFwv0QGqu njp/zdN6S4gcjn6KpPWP4NESk6q8DaZUUcHG0JUc8KoIdazwY6nWaQ1ixNK2s= X-QQ-XMRINFO: OD9hHCdaPRBwH5bRRRw8tsiH4UAatJqXfg== 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