From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 7CC03C121 for ; Fri, 22 Mar 2024 06:01:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711087317; cv=none; b=SgICmx6bpwgv7LWeYiFveLpX+6P5XwWaLzNHyIb1HmZ3nr0mzbsR6N9nwdX9vmeDd4+1Zf3jN2DzZ/8msjzJjzSdZHBAG3jwA3sR1DSyyVaFeK7TvEuLNX2CobYDwRo2psTf0KUwi9LBYfTUjR4hgpTDMFUS4SgYKTxvl3HSAiw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711087317; c=relaxed/simple; bh=oiexX4l+9bPLzhTtjB1M8IXJxZY34RYqmLKUedmwsok=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=aAyykptv8S0J7D8699dpyPo4kvrItMehfdK/Yv0c/jmCEaxMvm4X4vJ0FtgmhEHH/LX9YDkJOGy05njAm+zbdyYHI8293K1FS9zYn/Vw0SeM7U4jeO30nsTev+vfy2ORbhHo2vcOesS9wJUemUgIG0M9JIrTM4SMp/0C1EpNnlY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=j9h44js3; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="j9h44js3" Received: from [192.168.88.20] (91-154-34-181.elisa-laajakaista.fi [91.154.34.181]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 00ED2BEB; Fri, 22 Mar 2024 07:01:18 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1711087279; bh=oiexX4l+9bPLzhTtjB1M8IXJxZY34RYqmLKUedmwsok=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=j9h44js3DvAA7bAlcOob5gI7S/mzuV9kBsdvUyDg4ATubJvz6tfWZxvBkTSVhrJg6 Kucj7ZHTZkvewuY79MvkZ/KqcGf7bkQbsOlZfqga0mhFXwysrgG0iRaa2n4Nne6n+s MtY+N1J4iDFDhTEHGCKzMhDPr7GOkH/W2VXI6MsI= Message-ID: <222c0245-b8bc-48d8-b4e1-a9fb276774ae@ideasonboard.com> Date: Fri, 22 Mar 2024 08:01:44 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drm: zynqmp_dpsub: Always register bridge Content-Language: en-US To: Sean Anderson Cc: linux-arm-kernel@lists.infradead.org, Michal Simek , linux-kernel@vger.kernel.org, Daniel Vetter , David Airlie , Laurent Pinchart , dri-devel@lists.freedesktop.org, Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann References: <20240308204741.3631919-1-sean.anderson@linux.dev> From: Tomi Valkeinen Autocrypt: addr=tomi.valkeinen@ideasonboard.com; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi, On 08/03/2024 22:47, Sean Anderson wrote: > We must always register the DRM bridge, since zynqmp_dp_hpd_work_func > calls drm_bridge_hpd_notify, which in turn expects hpd_mutex to be > initialized. We do this before zynqmp_dpsub_drm_init since that calls > drm_bridge_attach. This fixes the following lockdep warning: > > [ 19.217084] ------------[ cut here ]------------ > [ 19.227530] DEBUG_LOCKS_WARN_ON(lock->magic != lock) > [ 19.227768] WARNING: CPU: 0 PID: 140 at kernel/locking/mutex.c:582 __mutex_lock+0x4bc/0x550 > [ 19.241696] Modules linked in: > [ 19.244937] CPU: 0 PID: 140 Comm: kworker/0:4 Not tainted 6.6.20+ #96 > [ 19.252046] Hardware name: xlnx,zynqmp (DT) > [ 19.256421] Workqueue: events zynqmp_dp_hpd_work_func > [ 19.261795] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > [ 19.269104] pc : __mutex_lock+0x4bc/0x550 > [ 19.273364] lr : __mutex_lock+0x4bc/0x550 > [ 19.277592] sp : ffffffc085c5bbe0 > [ 19.281066] x29: ffffffc085c5bbe0 x28: 0000000000000000 x27: ffffff88009417f8 > [ 19.288624] x26: ffffff8800941788 x25: ffffff8800020008 x24: ffffffc082aa3000 > [ 19.296227] x23: ffffffc080d90e3c x22: 0000000000000002 x21: 0000000000000000 > [ 19.303744] x20: 0000000000000000 x19: ffffff88002f5210 x18: 0000000000000000 > [ 19.311295] x17: 6c707369642e3030 x16: 3030613464662072 x15: 0720072007200720 > [ 19.318922] x14: 0000000000000000 x13: 284e4f5f4e524157 x12: 0000000000000001 > [ 19.326442] x11: 0001ffc085c5b940 x10: 0001ff88003f388b x9 : 0001ff88003f3888 > [ 19.334003] x8 : 0001ff88003f3888 x7 : 0000000000000000 x6 : 0000000000000000 > [ 19.341537] x5 : 0000000000000000 x4 : 0000000000001668 x3 : 0000000000000000 > [ 19.349054] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffffff88003f3880 > [ 19.356581] Call trace: > [ 19.359160] __mutex_lock+0x4bc/0x550 > [ 19.363032] mutex_lock_nested+0x24/0x30 > [ 19.367187] drm_bridge_hpd_notify+0x2c/0x6c > [ 19.371698] zynqmp_dp_hpd_work_func+0x44/0x54 > [ 19.376364] process_one_work+0x3ac/0x988 > [ 19.380660] worker_thread+0x398/0x694 > [ 19.384736] kthread+0x1bc/0x1c0 > [ 19.388241] ret_from_fork+0x10/0x20 > [ 19.392031] irq event stamp: 183 > [ 19.395450] hardirqs last enabled at (183): [] finish_task_switch.isra.0+0xa8/0x2d4 > [ 19.405140] hardirqs last disabled at (182): [] __schedule+0x714/0xd04 > [ 19.413612] softirqs last enabled at (114): [] srcu_invoke_callbacks+0x158/0x23c > [ 19.423128] softirqs last disabled at (110): [] srcu_invoke_callbacks+0x158/0x23c > [ 19.432614] ---[ end trace 0000000000000000 ]--- > > Fixes: eb2d64bfcc17 ("drm: xlnx: zynqmp_dpsub: Report HPD through the bridge") > Signed-off-by: Sean Anderson > --- > > drivers/gpu/drm/xlnx/zynqmp_dpsub.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/xlnx/zynqmp_dpsub.c b/drivers/gpu/drm/xlnx/zynqmp_dpsub.c > index 88eb33acd5f0..639fff2c693f 100644 > --- a/drivers/gpu/drm/xlnx/zynqmp_dpsub.c > +++ b/drivers/gpu/drm/xlnx/zynqmp_dpsub.c > @@ -256,12 +256,11 @@ static int zynqmp_dpsub_probe(struct platform_device *pdev) > if (ret) > goto err_dp; > > + drm_bridge_add(dpsub->bridge); > if (dpsub->dma_enabled) { > ret = zynqmp_dpsub_drm_init(dpsub); > if (ret) > goto err_disp; > - } else { > - drm_bridge_add(dpsub->bridge); > } > > dev_info(&pdev->dev, "ZynqMP DisplayPort Subsystem driver probed"); > @@ -288,9 +287,8 @@ static void zynqmp_dpsub_remove(struct platform_device *pdev) > > if (dpsub->drm) > zynqmp_dpsub_drm_cleanup(dpsub); > - else > - drm_bridge_remove(dpsub->bridge); > > + drm_bridge_remove(dpsub->bridge); > zynqmp_disp_remove(dpsub); > zynqmp_dp_remove(dpsub); > I sent a similar patch: https://lore.kernel.org/all/20240312-xilinx-dp-lock-fix-v1-1-1698f9f03bac@ideasonboard.com/ I have the drm_bridge_add() call in zynqmp_dp_probe(), as that's where the bridge is set up, so it felt like a logical place. You add it later, just before the bridge is used the first time. I like mine a bit more as it has all the bridge code in the same place, but I also wonder if there might be some risks in adding the bridge early (before zynqmp_disp_probe()), although I can't see any issue right away... In any case, as this works for me too: Reviewed-by: Tomi Valkeinen Tomi From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8E10FC47DD9 for ; Fri, 22 Mar 2024 06:02:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=yfn31WVdUn0FSBqCIxIsYbXKCNdaRBFa6yCRE3hGqPM=; 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d=ideasonboard.com; s=mail; t=1711087279; bh=oiexX4l+9bPLzhTtjB1M8IXJxZY34RYqmLKUedmwsok=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=j9h44js3DvAA7bAlcOob5gI7S/mzuV9kBsdvUyDg4ATubJvz6tfWZxvBkTSVhrJg6 Kucj7ZHTZkvewuY79MvkZ/KqcGf7bkQbsOlZfqga0mhFXwysrgG0iRaa2n4Nne6n+s MtY+N1J4iDFDhTEHGCKzMhDPr7GOkH/W2VXI6MsI= Message-ID: <222c0245-b8bc-48d8-b4e1-a9fb276774ae@ideasonboard.com> Date: Fri, 22 Mar 2024 08:01:44 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drm: zynqmp_dpsub: Always register bridge Content-Language: en-US To: Sean Anderson Cc: linux-arm-kernel@lists.infradead.org, Michal Simek , linux-kernel@vger.kernel.org, Daniel Vetter , David Airlie , Laurent Pinchart , dri-devel@lists.freedesktop.org, Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann References: <20240308204741.3631919-1-sean.anderson@linux.dev> From: Tomi Valkeinen Autocrypt: addr=tomi.valkeinen@ideasonboard.com; keydata= xsFNBE6ms0cBEACyizowecZqXfMZtnBniOieTuFdErHAUyxVgtmr0f5ZfIi9Z4l+uUN4Zdw2 wCEZjx3o0Z34diXBaMRJ3rAk9yB90UJAnLtb8A97Oq64DskLF81GCYB2P1i0qrG7UjpASgCA Ru0lVvxsWyIwSfoYoLrazbT1wkWRs8YBkkXQFfL7Mn3ZMoGPcpfwYH9O7bV1NslbmyJzRCMO eYV258gjCcwYlrkyIratlHCek4GrwV8Z9NQcjD5iLzrONjfafrWPwj6yn2RlL0mQEwt1lOvn LnI7QRtB3zxA3yB+FLsT1hx0va6xCHpX3QO2gBsyHCyVafFMrg3c/7IIWkDLngJxFgz6DLiA G4ld1QK/jsYqfP2GIMH1mFdjY+iagG4DqOsjip479HCWAptpNxSOCL6z3qxCU8MCz8iNOtZk DYXQWVscM5qgYSn+fmMM2qN+eoWlnCGVURZZLDjg387S2E1jT/dNTOsM/IqQj+ZROUZuRcF7 0RTtuU5q1HnbRNwy+23xeoSGuwmLQ2UsUk7Q5CnrjYfiPo3wHze8avK95JBoSd+WIRmV3uoO rXCoYOIRlDhg9XJTrbnQ3Ot5zOa0Y9c4IpyAlut6mDtxtKXr4+8OzjSVFww7tIwadTK3wDQv Bus4jxHjS6dz1g2ypT65qnHen6mUUH63lhzewqO9peAHJ0SLrQARAQABzTBUb21pIFZhbGtl aW5lbiA8dG9taS52YWxrZWluZW5AaWRlYXNvbmJvYXJkLmNvbT7CwY4EEwEIADgWIQTEOAw+ ll79gQef86f6PaqMvJYe9QUCX/HruAIbAwULCQgHAgYVCgkICwIEFgIDAQIeAQIXgAAKCRD6 PaqMvJYe9WmFD/99NGoD5lBJhlFDHMZvO+Op8vCwnIRZdTsyrtGl72rVh9xRfcSgYPZUvBuT VDxE53mY9HaZyu1eGMccYRBaTLJSfCXl/g317CrMNdY0k40b9YeIX10feiRYEWoDIPQ3tMmA 0nHDygzcnuPiPT68JYZ6tUOvAt7r6OX/litM+m2/E9mtp8xCoWOo/kYO4mOAIoMNvLB8vufi uBB4e/AvAjtny4ScuNV5c5q8MkfNIiOyag9QCiQ/JfoAqzXRjVb4VZG72AKaElwipiKCWEcU R4+Bu5Qbaxj7Cd36M/bI54OrbWWETJkVVSV1i0tghCd6HHyquTdFl7wYcz6cL1hn/6byVnD+ sR3BLvSBHYp8WSwv0TCuf6tLiNgHAO1hWiQ1pOoXyMEsxZlgPXT+wb4dbNVunckwqFjGxRbl Rz7apFT/ZRwbazEzEzNyrBOfB55xdipG/2+SmFn0oMFqFOBEszXLQVslh64lI0CMJm2OYYe3 PxHqYaztyeXsx13Bfnq9+bUynAQ4uW1P5DJ3OIRZWKmbQd/Me3Fq6TU57LsvwRgE0Le9PFQs dcP2071rMTpqTUteEgODJS4VDf4lXJfY91u32BJkiqM7/62Cqatcz5UWWHq5xeF03MIUTqdE qHWk3RJEoWHWQRzQfcx6Fn2fDAUKhAddvoopfcjAHfpAWJ+ENc7BTQROprNHARAAx0aat8GU hsusCLc4MIxOQwidecCTRc9Dz/7U2goUwhw2O5j9TPqLtp57VITmHILnvZf6q3QAho2QMQyE DDvHubrdtEoqaaSKxKkFie1uhWNNvXPhwkKLYieyL9m2JdU+b88HaDnpzdyTTR4uH7wk0bBa KbTSgIFDDe5lXInypewPO30TmYNkFSexnnM3n1PBCqiJXsJahE4ZQ+WnV5FbPUj8T2zXS2xk 0LZ0+DwKmZ0ZDovvdEWRWrz3UzJ8DLHb7blPpGhmqj3ANXQXC7mb9qJ6J/VSl61GbxIO2Dwb xPNkHk8fwnxlUBCOyBti/uD2uSTgKHNdabhVm2dgFNVuS1y3bBHbI/qjC3J7rWE0WiaHWEqy UVPk8rsph4rqITsj2RiY70vEW0SKePrChvET7D8P1UPqmveBNNtSS7In+DdZ5kUqLV7rJnM9 /4cwy+uZUt8cuCZlcA5u8IsBCNJudxEqBG10GHg1B6h1RZIz9Q9XfiBdaqa5+CjyFs8ua01c 9HmyfkuhXG2OLjfQuK+Ygd56mV3lq0aFdwbaX16DG22c6flkkBSjyWXYepFtHz9KsBS0DaZb 4IkLmZwEXpZcIOQjQ71fqlpiXkXSIaQ6YMEs8WjBbpP81h7QxWIfWtp+VnwNGc6nq5IQDESH mvQcsFS7d3eGVI6eyjCFdcAO8eMAEQEAAcLBXwQYAQIACQUCTqazRwIbDAAKCRD6PaqMvJYe 9fA7EACS6exUedsBKmt4pT7nqXBcRsqm6YzT6DeCM8PWMTeaVGHiR4TnNFiT3otD5UpYQI7S suYxoTdHrrrBzdlKe5rUWpzoZkVK6p0s9OIvGzLT0lrb0HC9iNDWT3JgpYDnk4Z2mFi6tTbq xKMtpVFRA6FjviGDRsfkfoURZI51nf2RSAk/A8BEDDZ7lgJHskYoklSpwyrXhkp9FHGMaYII m9EKuUTX9JPDG2FTthCBrdsgWYPdJQvM+zscq09vFMQ9Fykbx5N8z/oFEUy3ACyPqW2oyfvU CH5WDpWBG0s5BALp1gBJPytIAd/pY/5ZdNoi0Cx3+Z7jaBFEyYJdWy1hGddpkgnMjyOfLI7B CFrdecTZbR5upjNSDvQ7RG85SnpYJTIin+SAUazAeA2nS6gTZzumgtdw8XmVXZwdBfF+ICof 92UkbYcYNbzWO/GHgsNT1WnM4sa9lwCSWH8Fw1o/3bX1VVPEsnESOfxkNdu+gAF5S6+I6n3a ueeIlwJl5CpT5l8RpoZXEOVtXYn8zzOJ7oGZYINRV9Pf8qKGLf3Dft7zKBP832I3PQjeok7F yjt+9S+KgSFSHP3Pa4E7lsSdWhSlHYNdG/czhoUkSCN09C0rEK93wxACx3vtxPLjXu6RptBw 3dRq7n+mQChEB1am0BueV1JZaBboIL0AGlSJkm23kw== In-Reply-To: <20240308204741.3631919-1-sean.anderson@linux.dev> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240321_230152_195814_29F4813A X-CRM114-Status: GOOD ( 21.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On 08/03/2024 22:47, Sean Anderson wrote: > We must always register the DRM bridge, since zynqmp_dp_hpd_work_func > calls drm_bridge_hpd_notify, which in turn expects hpd_mutex to be > initialized. We do this before zynqmp_dpsub_drm_init since that calls > drm_bridge_attach. This fixes the following lockdep warning: > > [ 19.217084] ------------[ cut here ]------------ > [ 19.227530] DEBUG_LOCKS_WARN_ON(lock->magic != lock) > [ 19.227768] WARNING: CPU: 0 PID: 140 at kernel/locking/mutex.c:582 __mutex_lock+0x4bc/0x550 > [ 19.241696] Modules linked in: > [ 19.244937] CPU: 0 PID: 140 Comm: kworker/0:4 Not tainted 6.6.20+ #96 > [ 19.252046] Hardware name: xlnx,zynqmp (DT) > [ 19.256421] Workqueue: events zynqmp_dp_hpd_work_func > [ 19.261795] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > [ 19.269104] pc : __mutex_lock+0x4bc/0x550 > [ 19.273364] lr : __mutex_lock+0x4bc/0x550 > [ 19.277592] sp : ffffffc085c5bbe0 > [ 19.281066] x29: ffffffc085c5bbe0 x28: 0000000000000000 x27: ffffff88009417f8 > [ 19.288624] x26: ffffff8800941788 x25: ffffff8800020008 x24: ffffffc082aa3000 > [ 19.296227] x23: ffffffc080d90e3c x22: 0000000000000002 x21: 0000000000000000 > [ 19.303744] x20: 0000000000000000 x19: ffffff88002f5210 x18: 0000000000000000 > [ 19.311295] x17: 6c707369642e3030 x16: 3030613464662072 x15: 0720072007200720 > [ 19.318922] x14: 0000000000000000 x13: 284e4f5f4e524157 x12: 0000000000000001 > [ 19.326442] x11: 0001ffc085c5b940 x10: 0001ff88003f388b x9 : 0001ff88003f3888 > [ 19.334003] x8 : 0001ff88003f3888 x7 : 0000000000000000 x6 : 0000000000000000 > [ 19.341537] x5 : 0000000000000000 x4 : 0000000000001668 x3 : 0000000000000000 > [ 19.349054] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffffff88003f3880 > [ 19.356581] Call trace: > [ 19.359160] __mutex_lock+0x4bc/0x550 > [ 19.363032] mutex_lock_nested+0x24/0x30 > [ 19.367187] drm_bridge_hpd_notify+0x2c/0x6c > [ 19.371698] zynqmp_dp_hpd_work_func+0x44/0x54 > [ 19.376364] process_one_work+0x3ac/0x988 > [ 19.380660] worker_thread+0x398/0x694 > [ 19.384736] kthread+0x1bc/0x1c0 > [ 19.388241] ret_from_fork+0x10/0x20 > [ 19.392031] irq event stamp: 183 > [ 19.395450] hardirqs last enabled at (183): [] finish_task_switch.isra.0+0xa8/0x2d4 > [ 19.405140] hardirqs last disabled at (182): [] __schedule+0x714/0xd04 > [ 19.413612] softirqs last enabled at (114): [] srcu_invoke_callbacks+0x158/0x23c > [ 19.423128] softirqs last disabled at (110): [] srcu_invoke_callbacks+0x158/0x23c > [ 19.432614] ---[ end trace 0000000000000000 ]--- > > Fixes: eb2d64bfcc17 ("drm: xlnx: zynqmp_dpsub: Report HPD through the bridge") > Signed-off-by: Sean Anderson > --- > > drivers/gpu/drm/xlnx/zynqmp_dpsub.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/xlnx/zynqmp_dpsub.c b/drivers/gpu/drm/xlnx/zynqmp_dpsub.c > index 88eb33acd5f0..639fff2c693f 100644 > --- a/drivers/gpu/drm/xlnx/zynqmp_dpsub.c > +++ b/drivers/gpu/drm/xlnx/zynqmp_dpsub.c > @@ -256,12 +256,11 @@ static int zynqmp_dpsub_probe(struct platform_device *pdev) > if (ret) > goto err_dp; > > + drm_bridge_add(dpsub->bridge); > if (dpsub->dma_enabled) { > ret = zynqmp_dpsub_drm_init(dpsub); > if (ret) > goto err_disp; > - } else { > - drm_bridge_add(dpsub->bridge); > } > > dev_info(&pdev->dev, "ZynqMP DisplayPort Subsystem driver probed"); > @@ -288,9 +287,8 @@ static void zynqmp_dpsub_remove(struct platform_device *pdev) > > if (dpsub->drm) > zynqmp_dpsub_drm_cleanup(dpsub); > - else > - drm_bridge_remove(dpsub->bridge); > > + drm_bridge_remove(dpsub->bridge); > zynqmp_disp_remove(dpsub); > zynqmp_dp_remove(dpsub); > I sent a similar patch: https://lore.kernel.org/all/20240312-xilinx-dp-lock-fix-v1-1-1698f9f03bac@ideasonboard.com/ I have the drm_bridge_add() call in zynqmp_dp_probe(), as that's where the bridge is set up, so it felt like a logical place. You add it later, just before the bridge is used the first time. I like mine a bit more as it has all the bridge code in the same place, but I also wonder if there might be some risks in adding the bridge early (before zynqmp_disp_probe()), although I can't see any issue right away... In any case, as this works for me too: Reviewed-by: Tomi Valkeinen Tomi _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel