From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 722C33FF1BD; Fri, 15 May 2026 16:25:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778862335; cv=none; b=rJpN5z2pXVl5bePBaF2UuDMx/RjfJsjsQCDEktda0B/qWYz6rWRtnY1BcIw1fGDwqTAxpvrzv39xch+RuKJhyKltM7bjwKuGfuljJgIVKVNV1Ylkb1DjNBk6Y/SG70C4rdQhe0OTLUYlFKxp1tKPjEhoi9/EOqQNV2qMa+Keg3s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778862335; c=relaxed/simple; bh=JI8KR+GV0u4o6qiD/RkyAzRi2abWmG/mB90OCO5RKVA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VPdIuz2vVpwlCCC1LydSqn14jYt47jHTQRkaJPvGEGe7b+gFH5EPJBJRQ3CgYp7H9sf21M7sikKiKG4YBJLBMwqeZtqQAKQXUNBiZ4zJtVD6LfoVGdnTPzP+6frkvUnQTfmXCFc2Kmd047lLFxgQFcEc+ww+FPbZtmnMLQZQVOQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=W+67j09Q; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="W+67j09Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0339DC2BCB0; Fri, 15 May 2026 16:25:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778862335; bh=JI8KR+GV0u4o6qiD/RkyAzRi2abWmG/mB90OCO5RKVA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=W+67j09Q5tXDJbS0FWPh1Xqokr6rSCJq15Co59dxePXO9c/D2zviSw0hZEFxrxVZh 7gzX+jNKlN+duBdlU+HNnuc2LhIhXmSysutmCGCdc2n6vgvjmYVtbm5tQIEd54la5w ASaOLeWXDfRfrYsxW8WztLyR71QAfmPhYeEeiqMc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Guoniu Zhou , Laurent Pinchart , Hans Verkuil Subject: [PATCH 7.0 010/201] media: nxp: imx8-isi: Reduce minimum queued buffers from 2 to 0 Date: Fri, 15 May 2026 17:47:08 +0200 Message-ID: <20260515154658.760304540@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260515154658.538039039@linuxfoundation.org> References: <20260515154658.538039039@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guoniu Zhou commit 2f38622d0f85f317be9e6b131da6cd511db94fd2 upstream. Fix a hang issue when capturing a single frame with applications like cam in libcamera. It would hang waiting for the driver to complete the buffer, but streaming never starts because min_queued_buffers was set to 2. The ISI module uses a ping-pong buffer mechanism that requires two buffers to be programmed at all times. However, when fewer than 2 user buffers are available, the driver use internal discard buffers to fill the remaining slot(s). Reduce minimum queued buffers from 2 to 0 allows streaming to start without any queued buffers. Fixes: cf21f328fcaf ("media: nxp: Add i.MX8 ISI driver") Cc: stable@vger.kernel.org Signed-off-by: Guoniu Zhou Reviewed-by: Laurent Pinchart Link: https://patch.msgid.link/20260312-isi_min_buffers-v2-1-d5ea1c79ad81@nxp.com Signed-off-by: Laurent Pinchart Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman --- drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c @@ -1410,7 +1410,7 @@ int mxc_isi_video_register(struct mxc_is q->mem_ops = &vb2_dma_contig_memops; q->buf_struct_size = sizeof(struct mxc_isi_buffer); q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; - q->min_queued_buffers = 2; + q->min_queued_buffers = 0; q->lock = &video->lock; q->dev = pipe->isi->dev;