Re: [PATCH] mmc: moxart: Stop host before releasing DMA channels

[Ulf Hansson]

On Wed, Oct 21, 2026 at 3:06 PM Guanxin Li <bruceli20040604@xxxxxxxxx> wrote:
>
> moxart_remove() currently releases the TX and RX DMA channels before
> calling mmc_remove_host(). This allows the MMC host to remain active while
> the DMA channels are being torn down.
>
> Call mmc_remove_host() before masking controller interrupts and releasing
> the DMA channels. Terminate any active DMA transfers before releasing
> their channels.
>
> Keep the power and clock shutdown after DMA teardown. Do not call
> mmc_free_host(), since the host is allocated with devm_mmc_alloc_host()
> and is released automatically by devres.
>
> Signed-off-by: Guanxin Li <bruceli20040604@xxxxxxxxx>

Applied for next, thanks!

Kind regards
Uffe


> ---
>  drivers/mmc/host/moxart-mmc.c | 20 ++++++++++++++++----
>  1 file changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c
> index 28aed13549a6..bece33f4792d 100644
> --- a/drivers/mmc/host/moxart-mmc.c
> +++ b/drivers/mmc/host/moxart-mmc.c
> @@ -684,13 +684,25 @@ static void moxart_remove(struct platform_device *pdev)
>         struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
>         struct moxart_host *host = mmc_priv(mmc);
>
> -       if (!IS_ERR_OR_NULL(host->dma_chan_tx))
> -               dma_release_channel(host->dma_chan_tx);
> -       if (!IS_ERR_OR_NULL(host->dma_chan_rx))
> -               dma_release_channel(host->dma_chan_rx);
> +       /*
> +        * Stop the MMC host before releasing DMA channels.
> +        * Keep controller interrupts enabled during MMC teardown.
> +        */
>         mmc_remove_host(mmc);
>
>         writel(0, host->base + REG_INTERRUPT_MASK);
> +
> +       if (!IS_ERR_OR_NULL(host->dma_chan_tx)) {
> +               dmaengine_terminate_sync(host->dma_chan_tx);
> +               dma_release_channel(host->dma_chan_tx);
> +               host->dma_chan_tx = NULL;
> +       }
> +       if (!IS_ERR_OR_NULL(host->dma_chan_rx)) {
> +               dmaengine_terminate_sync(host->dma_chan_rx);
> +               dma_release_channel(host->dma_chan_rx);
> +               host->dma_chan_rx = NULL;
> +       }
> +
>         writel(0, host->base + REG_POWER_CONTROL);
>         writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
>                host->base + REG_CLOCK_CONTROL);
> --
> 2.43.0
>