[PATCH v2] dmaengine: zynqmp_dma: Add shutdown operation support

[PATCH v2] dmaengine: zynqmp_dma: Add shutdown operation support

[Abin Joseph]

Add shutdown callback to ensure that DMA operations are properly stopped
and resources are released during system shutdown or kexec.
Fix incorrect PM state handling in the remove function that was causing
clock disabled warning during the shutdown operation since the device
may already be suspended with clock disabled, causing the clock
framework to warn about the double-disable attempt. The current check
ensures runtime_suspend is only called when the device is in active
power state, preventing clock warnings during shutdown while maintaining
proper clean up during normal remove operations.

Signed-off-by: Abin Joseph <abin.joseph@amd.com>
---

Changes in v2:
Update the shutdown to perform same operations 
as remove.

---
 drivers/dma/xilinx/zynqmp_dma.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
index d05fc5fcc77d..0b03c2092c28 100644
--- a/drivers/dma/xilinx/zynqmp_dma.c
+++ b/drivers/dma/xilinx/zynqmp_dma.c
@@ -1173,9 +1173,18 @@ static void zynqmp_dma_remove(struct platform_device *pdev)
 	dma_async_device_unregister(&zdev->common);
 
 	zynqmp_dma_chan_remove(zdev->chan);
-	pm_runtime_disable(zdev->dev);
-	if (!pm_runtime_enabled(zdev->dev))
+	if (pm_runtime_active(zdev->dev))
 		zynqmp_dma_runtime_suspend(zdev->dev);
+	pm_runtime_disable(zdev->dev);
+}
+
+/**
+ * zynqmp_dma_shutdown - Driver shutdown function
+ * @pdev: Pointer to the platform_device structure
+ */
+static void zynqmp_dma_shutdown(struct platform_device *pdev)
+{
+	zynqmp_dma_remove(pdev);
 }
 
 static const struct of_device_id zynqmp_dma_of_match[] = {
@@ -1193,6 +1202,7 @@ static struct platform_driver zynqmp_dma_driver = {
 	},
 	.probe = zynqmp_dma_probe,
 	.remove = zynqmp_dma_remove,
+	.shutdown = zynqmp_dma_shutdown,
 };
 
 module_platform_driver(zynqmp_dma_driver);
-- 
2.34.1

RE: [PATCH v2] dmaengine: zynqmp_dma: Add shutdown operation support

[Pandey, Radhey Shyam]

[AMD Official Use Only - AMD Internal Distribution Only]

> -----Original Message-----
> From: Abin Joseph <abin.joseph@amd.com>
> Sent: Saturday, July 12, 2025 8:48 PM
> To: vkoul@kernel.org; Simek, Michal <michal.simek@amd.com>;
> yanzhen@vivo.com; Pandey, Radhey Shyam <radhey.shyam.pandey@amd.com>;
> palmer@rivosinc.com; u.kleine-koenig@baylibre.com
> Cc: git (AMD-Xilinx) <git@amd.com>; Joseph, Abin <Abin.Joseph@amd.com>;
> dmaengine@vger.kernel.org; linux-arm-kernel@lists.infradead.org; linux-
> kernel@vger.kernel.org
> Subject: [PATCH v2] dmaengine: zynqmp_dma: Add shutdown operation support
>
> Add shutdown callback to ensure that DMA operations are properly stopped
> and resources are released during system shutdown or kexec.
> Fix incorrect PM state handling in the remove function that was causing
> clock disabled warning during the shutdown operation since the device

Rephrase - it. Shutdown was not implemented earlier.

Say extend remove function for shutdown usecase.

> may already be suspended with clock disabled, causing the clock
> framework to warn about the double-disable attempt. The current check
> ensures runtime_suspend is only called when the device is in active
> power state, preventing clock warnings during shutdown while maintaining

Explain pm_runtime_enabled/ pm_runtime_active usage.

> proper clean up during normal remove operations.
>
> Signed-off-by: Abin Joseph <abin.joseph@amd.com>
> ---
>
> Changes in v2:
> Update the shutdown to perform same operations
> as remove.
>
> ---
>  drivers/dma/xilinx/zynqmp_dma.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
> index d05fc5fcc77d..0b03c2092c28 100644
> --- a/drivers/dma/xilinx/zynqmp_dma.c
> +++ b/drivers/dma/xilinx/zynqmp_dma.c
> @@ -1173,9 +1173,18 @@ static void zynqmp_dma_remove(struct platform_device
> *pdev)
>       dma_async_device_unregister(&zdev->common);
>
>       zynqmp_dma_chan_remove(zdev->chan);
> -     pm_runtime_disable(zdev->dev);
> -     if (!pm_runtime_enabled(zdev->dev))
> +     if (pm_runtime_active(zdev->dev))
>               zynqmp_dma_runtime_suspend(zdev->dev);
> +     pm_runtime_disable(zdev->dev);
> +}
> +
> +/**
> + * zynqmp_dma_shutdown - Driver shutdown function
> + * @pdev: Pointer to the platform_device structure
> + */

Why we need separate handler ? Just reuse the remove directly ?
See https://lore.kernel.org/all/1748977771-714153-1-git-send-email-radhey.shyam.pandey@amd.com/

> +static void zynqmp_dma_shutdown(struct platform_device *pdev)
> +{
> +     zynqmp_dma_remove(pdev);
>  }
>
>  static const struct of_device_id zynqmp_dma_of_match[] = {
> @@ -1193,6 +1202,7 @@ static struct platform_driver zynqmp_dma_driver = {
>       },
>       .probe = zynqmp_dma_probe,
>       .remove = zynqmp_dma_remove,
> +     .shutdown = zynqmp_dma_shutdown,
>  };
>
>  module_platform_driver(zynqmp_dma_driver);
> --
> 2.34.1