linux-kernel - [PATCH 04/12] media: stm32: dcmi: stop the dma transfer on overrun

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251218-stm32-dcmi-dma-chaining-v1-4-39948ca6cbf6@foss.st.com>
Date: Thu, 18 Dec 2025 19:44:44 +0100
From: Alain Volmat <alain.volmat@...s.st.com>
To: Hugues Fruchet <hugues.fruchet@...s.st.com>,
        Mauro Carvalho Chehab
	<mchehab@...nel.org>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        "Alexandre
 Torgue" <alexandre.torgue@...s.st.com>,
        Rob Herring <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Sumit Semwal <sumit.semwal@...aro.org>,
        Christian König
	<christian.koenig@....com>
CC: <linux-media@...r.kernel.org>, <linux-stm32@...md-mailman.stormreply.com>,
        <linux-arm-kernel@...ts.infradead.org>, <linux-kernel@...r.kernel.org>,
        <devicetree@...r.kernel.org>, <dri-devel@...ts.freedesktop.org>,
        <linaro-mm-sig@...ts.linaro.org>,
        Alain Volmat <alain.volmat@...s.st.com>
Subject: [PATCH 04/12] media: stm32: dcmi: stop the dma transfer on overrun

Ensure to stop the dma transfer whenever receiving a overrun
to avoid having a buffer partially filled with a frame and
partially with the next frame.

Signed-off-by: Alain Volmat <alain.volmat@...s.st.com>
---
 drivers/media/platform/st/stm32/stm32-dcmi.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/media/platform/st/stm32/stm32-dcmi.c b/drivers/media/platform/st/stm32/stm32-dcmi.c
index d8ef06bd7506..fa33acc34eab 100644
--- a/drivers/media/platform/st/stm32/stm32-dcmi.c
+++ b/drivers/media/platform/st/stm32/stm32-dcmi.c
@@ -402,9 +402,21 @@ static irqreturn_t dcmi_irq_thread(int irq, void *arg)
 	spin_lock_irq(&dcmi->irqlock);
 
 	if (dcmi->misr & IT_OVR) {
+		/* Disable capture */
+		reg_clear(dcmi->regs, DCMI_CR, CR_CAPTURE);
+
 		dcmi->overrun_count++;
+
 		if (dcmi->overrun_count > OVERRUN_ERROR_THRESHOLD)
 			dcmi->errors_count++;
+
+		spin_unlock_irq(&dcmi->irqlock);
+		dmaengine_terminate_sync(dcmi->dma_chan);
+
+		if (dcmi_restart_capture(dcmi))
+			dev_err(dcmi->dev, "%s: Cannot restart capture\n", __func__);
+
+		return IRQ_HANDLED;
 	}
 	if (dcmi->misr & IT_ERR)
 		dcmi->errors_count++;

-- 
2.34.1