From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) (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 26D0820B2F; Wed, 29 Nov 2023 14:03:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="bu8LQ5GM" Received: from [100.122.216.38] (ec2-34-240-57-77.eu-west-1.compute.amazonaws.com [34.240.57.77]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: benjamin.gaignard) by madras.collabora.co.uk (Postfix) with ESMTPSA id 97DA56602F24; Wed, 29 Nov 2023 14:03:22 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1701266603; bh=b6+ijhuLS88ltAwu7BXjh1rAJvOdjCKQaRzxoejPv4I=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=bu8LQ5GMgFuLSvVASEwXe4Q5ZReofSektOwVrjhLicV/nbfkoOnfdHR/M3EswcMW7 s1dsjIA+9VOfS0GqbQotfBRMxj6Darr13HwKvZ75gw3T9YjPg4T1xC6/p5Mvkd/UnW pLEmNvoDTrNXeTegisVMJ2+Etjg7ZalJjYhXbrZInb0o9jok1EHgWrNh/sXyc4m4pk NilB+X55GcW+iL6aj1skRM11qNQvktH+Fnpm2g2tlF8zPkAIF9YuVHAYmJkg495R3w 6Z3BgFtnRuHXZHVFbgd7TWcFsKyRamG0BTbcXrtj8FYwMRMqx7fsmDeXZOBsq2xBWD OIn9WxkVfy+Gg== Message-ID: <54881dbe-e722-4a2d-840d-972d1a58331a@collabora.com> Date: Wed, 29 Nov 2023 15:03:20 +0100 Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 27/55] media: sun6i-isp: Stop abusing of min_buffers_needed field Content-Language: en-US To: Paul Kocialkowski Cc: hverkuil@xs4all.nl, mchehab@kernel.org, tfiga@chromium.org, m.szyprowski@samsung.com, matt.ranostay@konsulko.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-staging@lists.linux.dev, kernel@collabora.com, Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , linux-sunxi@lists.linux.dev References: <20231127165454.166373-1-benjamin.gaignard@collabora.com> <20231127165454.166373-28-benjamin.gaignard@collabora.com> From: Benjamin Gaignard In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Le 29/11/2023 à 14:40, Paul Kocialkowski a écrit : > Hi Benjamin, > > On Mon 27 Nov 23, 17:54, Benjamin Gaignard wrote: >> 'min_buffers_needed' is suppose to be used to indicate the number >> of buffers needed by DMA engine to start streaming. >> sun6i-isp driver doesn't use DMA engine and just want to specify >> the minimum number of buffers to allocate when calling VIDIOC_REQBUFS. >> That 'min_reqbufs_allocation' field purpose so use it. > The hardware actually has its own DMA engine. It can work with just one buffer > though (which will never be returned to userspace). But I think we should still > require at least two buffers allocated, otherwise the driver will be of no use > at all. > > So I don't think the commit message here is correct. That is exactly the info I hope to get for this first series since I don't know each hardware block details. I will remove this commit and make the driver use min_queued_buffers field instead so that will fit with it needs. Thanks, Benjamin > > Cheers, > > Paul > >> Signed-off-by: Benjamin Gaignard >> CC: Paul Kocialkowski >> CC: Chen-Yu Tsai >> CC: Jernej Skrabec >> CC: Samuel Holland >> CC: linux-sunxi@lists.linux.dev >> --- >> drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c | 2 +- >> drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c | 2 +- >> 2 files changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c >> index 1595a9607775..f47f9946c19f 100644 >> --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c >> +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c >> @@ -660,7 +660,7 @@ int sun6i_isp_capture_setup(struct sun6i_isp_device *isp_dev) >> queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); >> queue->ops = &sun6i_isp_capture_queue_ops; >> queue->mem_ops = &vb2_dma_contig_memops; >> - queue->min_buffers_needed = 2; >> + queue->min_reqbufs_allocation = 2; >> queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; >> queue->lock = &capture->lock; >> queue->dev = isp_dev->dev; >> diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c >> index e28be895b486..259f6bfcb620 100644 >> --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c >> +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c >> @@ -489,7 +489,7 @@ int sun6i_isp_params_setup(struct sun6i_isp_device *isp_dev) >> queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); >> queue->ops = &sun6i_isp_params_queue_ops; >> queue->mem_ops = &vb2_vmalloc_memops; >> - queue->min_buffers_needed = 1; >> + queue->min_reqbufs_allocation = 1; >> queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; >> queue->lock = ¶ms->lock; >> queue->dev = isp_dev->dev; >> -- >> 2.39.2 >>