[PATCH 07/17] i3c: mipi-i3c-hci: Manage DMA deallocation via devres action

[Frank Li]

On Fri, Dec 19, 2025 at 04:45:24PM +0200, Adrian Hunter wrote:
> The driver already uses devres for resource management, but the standard
> resource-managed DMA allocation helpers cannot be used because they assume
> the DMA device matches the managed device.
>
> To address this, factor out the deallocation logic from hci_dma_cleanup()
> into a new helper, hci_dma_free(), and register it as a devres action.
>
> Signed-off-by: Adrian Hunter <adrian.hunter at intel.com>
> ---
>  drivers/i3c/master/mipi-i3c-hci/dma.c | 53 ++++++++++++++++++---------
>  1 file changed, 36 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c
> index 54849aa98fad..703d5cf79d5e 100644
> --- a/drivers/i3c/master/mipi-i3c-hci/dma.c
> +++ b/drivers/i3c/master/mipi-i3c-hci/dma.c
> @@ -146,30 +146,18 @@ struct hci_dma_dev_ibi_data {
>  	unsigned int max_len;
>  };
>
> -static void hci_dma_cleanup(struct i3c_hci *hci)
> +static void hci_dma_free(void *data)

can you move hci_dma_free() below hci_dma_cleanup() to make patch look
better to review?

>  {
> +	struct i3c_hci *hci = data;
>  	struct hci_rings_data *rings = hci->io_data;
>  	struct hci_rh_data *rh;
> -	unsigned int i;
>
>  	if (!rings)
>  		return;
>
> -	for (i = 0; i < rings->total; i++) {
> -		rh = &rings->headers[i];
> -
> -		rh_reg_write(INTR_SIGNAL_ENABLE, 0);
> -		rh_reg_write(RING_CONTROL, 0);
> -	}
> -
> -	i3c_hci_sync_irq_inactive(hci);
> -
> -	for (i = 0; i < rings->total; i++) {
> +	for (int i = 0; i < rings->total; i++) {
>  		rh = &rings->headers[i];
>
> -		rh_reg_write(CR_SETUP, 0);
> -		rh_reg_write(IBI_SETUP, 0);
> -
>  		if (rh->xfer)
>  			dma_free_coherent(rings->sysdev,
>  					  rh->xfer_struct_sz * rh->xfer_entries,
> @@ -190,12 +178,38 @@ static void hci_dma_cleanup(struct i3c_hci *hci)
>  		kfree(rh->ibi_data);
>  	}
>
> -	rhs_reg_write(CONTROL, 0);
> -
>  	kfree(rings);
>  	hci->io_data = NULL;
>  }
>
> +static void hci_dma_cleanup(struct i3c_hci *hci)
> +{
> +	struct hci_rings_data *rings = hci->io_data;
> +	struct hci_rh_data *rh;
> +	unsigned int i;
> +
> +	if (!rings)
> +		return;
> +
> +	for (i = 0; i < rings->total; i++) {
> +		rh = &rings->headers[i];
> +
> +		rh_reg_write(INTR_SIGNAL_ENABLE, 0);
> +		rh_reg_write(RING_CONTROL, 0);
> +	}
> +
> +	i3c_hci_sync_irq_inactive(hci);
> +
> +	for (i = 0; i < rings->total; i++) {
> +		rh = &rings->headers[i];
> +
> +		rh_reg_write(CR_SETUP, 0);
> +		rh_reg_write(IBI_SETUP, 0);
> +	}
> +
> +	rhs_reg_write(CONTROL, 0);
> +}
> +
>  static int hci_dma_init(struct i3c_hci *hci)
>  {
>  	struct hci_rings_data *rings;
> @@ -359,10 +373,15 @@ static int hci_dma_init(struct i3c_hci *hci)
>  					   RING_CTRL_RUN_STOP);
>  	}
>
> +	ret = devm_add_action(hci->master.dev.parent, hci_dma_free, hci);
> +	if (ret)
> +		goto err_out;
> +

use devm_add_action_or_reset(), so needn't goto

Frank
>  	return 0;
>
>  err_out:
>  	hci_dma_cleanup(hci);
> +	hci_dma_free(hci);
>  	return ret;
>  }
>
> --
> 2.51.0
>
>
> --
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