RE: [PATCH v3] dmaengine: zynqmp_dma: Add shutdown operation support

From: Pandey, Radhey Shyam
Date: Wed Aug 13 2025 - 02:53:05 EST


[Public]

> -----Original Message-----
> From: Abin Joseph <abin.joseph@xxxxxxx>
> Sent: Tuesday, July 22, 2025 12:33 PM
> To: vkoul@xxxxxxxxxx; Simek, Michal <michal.simek@xxxxxxx>;
> yanzhen@xxxxxxxx; Pandey, Radhey Shyam <radhey.shyam.pandey@xxxxxxx>;
> palmer@xxxxxxxxxxxx; u.kleine-koenig@xxxxxxxxxxxx
> Cc: git (AMD-Xilinx) <git@xxxxxxx>; Joseph, Abin <Abin.Joseph@xxxxxxx>;
> dmaengine@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: [PATCH v3] 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 operations.
> Fix incorrect PM state handling in the remove function that was causing
> clock disable warnings during the shutdown operations, which was not
> implemented earlier. The original logic used pm_runtime_enabled() check
> after calling the pm_runtime_disable(), would always evaluate to true
> after the disable call, which leads to unconditionally calling the
> runtime_suspend regardless of the device's actual power state.
>
> During shutdown, the device may already be suspended with clock disabled
> from the autosuspend timer, causing the clock framework to warn about
> the double-disable attempt. The pm_runtime_active() function checks the
> actual device power state rather than the PM subsystem's enabled/disabled
> status. ensuring the runtime_suspend is only called when the device is in
> active power state. This prevents clock warnings during shutdown while
> maintaining proper cleanup during normal remove operations.
>
> Signed-off-by: Abin Joseph <abin.joseph@xxxxxxx>

Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxx>
Thanks!
> ---
>
> Changes in v3:
> Update the commit description
> Update to call remove directly from shutdown hook.
>
> Changes in v2:
> Update the shutdown to perform same operations as remove.
>
> ---
> drivers/dma/xilinx/zynqmp_dma.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
> index d05fc5fcc77d..f7e584de4335 100644
> --- a/drivers/dma/xilinx/zynqmp_dma.c
> +++ b/drivers/dma/xilinx/zynqmp_dma.c
> @@ -1173,9 +1173,9 @@ 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);
> }
>
> static const struct of_device_id zynqmp_dma_of_match[] = {
> @@ -1193,6 +1193,7 @@ static struct platform_driver zynqmp_dma_driver = {
> },
> .probe = zynqmp_dma_probe,
> .remove = zynqmp_dma_remove,
> + .shutdown = zynqmp_dma_remove,
> };
>
> module_platform_driver(zynqmp_dma_driver);
> --
> 2.43.0