linux-kernel - [PATCH 06/11] dmaengine: imx-sdma: make use of devm_add_action_or_reset to unregiser the dma

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Message-Id: <20250903-v6-16-topic-sdma-v1-6-ac7bab629e8b@pengutronix.de>
Date: Wed, 03 Sep 2025 15:06:14 +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 06/11] 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 since we want to turn of the IRQs before
doing the dma_async_device_unregister().

This removes the last goto error handling within the probe function and
further trims the remove() function. Instead of freeing the irq, we can
disable it and let the devm-irq do the job to free the irq, since the
only purpose was to have the irqs disabled before calling
dma_async_device_unregister().

Signed-off-by: Marco Felsch <m.felsch@...gutronix.de>
---
 drivers/dma/imx-sdma.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 5a571d3f33158813e0c56484600a49b19a6a72e2..f6bb2f88a62781c0431336c365fa30c46f1401ad 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -2232,6 +2232,14 @@ 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;
@@ -2358,10 +2366,12 @@ static int sdma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	devm_add_action_or_reset(dev, sdma_dma_device_unregister_action, sdma);
+
 	ret = of_dma_controller_register(np, sdma_xlate, sdma);
 	if (ret) {
 		dev_err(dev, "failed to register controller\n");
-		goto err_register;
+		return ret;
 	}
 
 	spba_bus = of_find_compatible_node(NULL, NULL, "fsl,spba-bus");
@@ -2388,11 +2398,6 @@ 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)
@@ -2400,8 +2405,6 @@ static void sdma_remove(struct platform_device *pdev)
 	struct sdma_engine *sdma = platform_get_drvdata(pdev);
 	int i;
 
-	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];

-- 
2.47.2