public inbox for linux-arm-kernel@lists.infradead.org
 help / color / mirror / Atom feed
From: Amelie Delaunay <amelie.delaunay@foss.st.com>
To: Vinod Koul <vkoul@kernel.org>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: <dmaengine@vger.kernel.org>,
	<linux-stm32@st-md-mailman.stormreply.com>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>,
	Alain Volmat <alain.volmat@foss.st.com>,
	Amelie Delaunay <amelie.delaunay@foss.st.com>
Subject: [PATCH] dmaengine: stm32-dma: set dma_device max_sg_burst
Date: Mon, 17 Jan 2022 10:17:40 +0100	[thread overview]
Message-ID: <20220117091740.11064-1-amelie.delaunay@foss.st.com> (raw)

Some stm32-dma consumers [1] rather use dma_get_slave_caps() to get
max_sg_burst of their DMA channel as dma_get_max_seg_size() is specific to
the DMA controller.
All stm32-dma channels have the same features so, don't need to implement
device_caps ops. Let dma_get_slave_caps() relies on dma_device
configuration.
That's why this patch sets dma_device max_sg_burst to the maximum segment
size, which is the maximum of data items that can be transferred without
software intervention.

[1] https://lore.kernel.org/lkml/20220110103739.118426-1-alain.volmat@foss.st.com/
    "media: stm32: dcmi: create a dma scatterlist based on DMA max_sg_burst value"

Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
---
 drivers/dma/stm32-dma.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index 83a37a6955a3..d2365fab1b7a 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -1389,6 +1389,7 @@ static int stm32_dma_probe(struct platform_device *pdev)
 	dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 	dd->copy_align = DMAENGINE_ALIGN_32_BYTES;
 	dd->max_burst = STM32_DMA_MAX_BURST;
+	dd->max_sg_burst = STM32_DMA_ALIGNED_MAX_DATA_ITEMS;
 	dd->descriptor_reuse = true;
 	dd->dev = &pdev->dev;
 	INIT_LIST_HEAD(&dd->channels);
-- 
2.25.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

             reply	other threads:[~2022-01-17  9:19 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-17  9:17 Amelie Delaunay [this message]
2022-01-17  9:25 ` [PATCH] dmaengine: stm32-dma: set dma_device max_sg_burst Alain Volmat
2022-02-15  5:42 ` Vinod Koul

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220117091740.11064-1-amelie.delaunay@foss.st.com \
    --to=amelie.delaunay@foss.st.com \
    --cc=alain.volmat@foss.st.com \
    --cc=alexandre.torgue@foss.st.com \
    --cc=dmaengine@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-stm32@st-md-mailman.stormreply.com \
    --cc=mcoquelin.stm32@gmail.com \
    --cc=vkoul@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox