linux-kernel - [PATCH v2 08/10] dmaengine: imx-sdma: make use of devm_add_action_or_reset to unregiser the dma

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: <20250911-v6-16-topic-sdma-v2-8-d315f56343b5@pengutronix.de>
Date: Thu, 11 Sep 2025 23:56:49 +0200
From: Marco Felsch <m.felsch@...gutronix.de>
To: Vinod Koul <vkoul@...nel.org>, Shawn Guo <shawnguo@...nel.org>, 
 Sascha Hauer <s.hauer@...gutronix.de>, 
 Pengutronix Kernel Team <kernel@...gutronix.de>, 
 Fabio Estevam <festevam@...il.com>, Jiada Wang <jiada_wang@...tor.com>
Cc: dmaengine@...r.kernel.org, imx@...ts.linux.dev, 
 linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org, 
 Marco Felsch <m.felsch@...gutronix.de>
Subject: [PATCH v2 08/10] dmaengine: imx-sdma: make use of
 devm_add_action_or_reset to unregiser the dma_device

Make use of the devm_add_action_or_reset() to register a custom devm_
release hook. This is required to turn off the IRQs before calling
dma_async_device_unregister().

Furthermore it removes the last goto error handling within probe() and
trims the remove().

Make use of disable_irq() and let the devm-irq do the job to free the
IRQ, because the only purpose of using devm_free_irq() was to disable
the IRQ before calling dma_async_device_unregister().

Signed-off-by: Marco Felsch <m.felsch@...gutronix.de>
---
 drivers/dma/imx-sdma.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index d39589c20c4b2a26d0239feb86cce8d5a0f5acdd..d6d0d4300f540268a3ab4a6b14af685f7b93275a 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -2264,6 +2264,14 @@ static struct dma_chan *sdma_xlate(struct of_phandle_args *dma_spec,
 				     ofdma->of_node);
 }
 
+static void sdma_dma_device_unregister_action(void *data)
+{
+	struct sdma_engine *sdma = data;
+
+	disable_irq(sdma->irq);
+	dma_async_device_unregister(&sdma->dma_device);
+}
+
 static int sdma_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -2388,10 +2396,16 @@ static int sdma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ret = devm_add_action_or_reset(dev, sdma_dma_device_unregister_action, sdma);
+	if (ret) {
+		dev_err(dev, "Unable to register release hook\n");
+		return ret;
+	}
+
 	ret = of_dma_controller_register(np, sdma_xlate, sdma);
 	if (ret) {
 		dev_err(dev, "failed to register controller\n");
-		goto err_register;
+		return ret;
 	}
 
 	/*
@@ -2410,11 +2424,6 @@ static int sdma_probe(struct platform_device *pdev)
 	}
 
 	return 0;
-
-err_register:
-	dma_async_device_unregister(&sdma->dma_device);
-
-	return ret;
 }
 
 static void sdma_remove(struct platform_device *pdev)
@@ -2423,8 +2432,6 @@ static void sdma_remove(struct platform_device *pdev)
 	int i;
 
 	of_dma_controller_free(sdma->dev->of_node);
-	devm_free_irq(&pdev->dev, sdma->irq, sdma);
-	dma_async_device_unregister(&sdma->dma_device);
 	/* Kill the tasklet */
 	for (i = 0; i < MAX_DMA_CHANNELS; i++) {
 		struct sdma_channel *sdmac = &sdma->channel[i];

-- 
2.47.3