Re: [PATCHv2] dmaengine: ppc4xx: use devm_platform_ioremap_resource()

From: Frank Li

Date: Mon Sep 14 2026 - 12:33:23 EST


On Fri, Sep 11, 2026 at 03:06:40PM -0700, Rosen Penev wrote:
> Replace the open-coded sequence of of_address_to_resource(),
> request_mem_region(), and ioremap() with devm_platform_ioremap_resource().
> This eliminates error-path cleanup for both the memory region and the
> ioremap.
>
> The two separate initcodes PPC_ADMA_INIT_MEMRES and PPC_ADMA_INIT_MEMREG
> are collapsed into PPC_ADMA_INIT_MEMRES since the combined call covers
> both steps.
>
> Also emove unused PPC_ADMA_INIT_MEMREG enum value

emove? can you bound all ppc4xx patches to one patch serial to avoid
pick up conflict between these patches.

Frank

>
> The PPC_ADMA_INIT_MEMREG error code is no longer used after converting
> to devm_platform_ioremap_resource(). Remove it from the enum and the
> corresponding error string.
>
> Assisted-by: LLM
> Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
> ---
> v2: cut some stuff from description
> drivers/dma/ppc4xx/adma.c | 46 +++++----------------------------------
> 1 file changed, 6 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/dma/ppc4xx/adma.c b/drivers/dma/ppc4xx/adma.c
> index 39498779e241..17b60704a702 100644
> --- a/drivers/dma/ppc4xx/adma.c
> +++ b/drivers/dma/ppc4xx/adma.c
> @@ -37,7 +37,6 @@
> enum ppc_adma_init_code {
> PPC_ADMA_INIT_OK = 0,
> PPC_ADMA_INIT_MEMRES,
> - PPC_ADMA_INIT_MEMREG,
> PPC_ADMA_INIT_ALLOC,
> PPC_ADMA_INIT_COHERENT,
> PPC_ADMA_INIT_CHANNEL,
> @@ -49,7 +48,6 @@ enum ppc_adma_init_code {
> static char *ppc_adma_errors[] = {
> [PPC_ADMA_INIT_OK] = "ok",
> [PPC_ADMA_INIT_MEMRES] = "failed to get memory resource",
> - [PPC_ADMA_INIT_MEMREG] = "failed to request memory region",
> [PPC_ADMA_INIT_ALLOC] = "failed to allocate memory for adev "
> "structure",
> [PPC_ADMA_INIT_COHERENT] = "failed to allocate coherent memory for "
> @@ -3997,7 +3995,6 @@ static void ppc440spe_adma_release_irqs(struct ppc440spe_adma_device *adev,
> static int ppc440spe_adma_probe(struct platform_device *ofdev)
> {
> struct device_node *np = ofdev->dev.of_node;
> - struct resource res;
> struct ppc440spe_adma_device *adev;
> struct ppc440spe_adma_chan *chan;
> struct ppc_dma_chan_ref *ref, *_ref;
> @@ -4040,28 +4037,12 @@ static int ppc440spe_adma_probe(struct platform_device *ofdev)
> pool_size <<= 2;
> }
>
> - if (of_address_to_resource(np, 0, &res)) {
> - dev_err(&ofdev->dev, "failed to get memory resource\n");
> - initcode = PPC_ADMA_INIT_MEMRES;
> - ret = -ENODEV;
> - goto out;
> - }
> -
> - if (!request_mem_region(res.start, resource_size(&res),
> - dev_driver_string(&ofdev->dev))) {
> - dev_err(&ofdev->dev, "failed to request memory region %pR\n",
> - &res);
> - initcode = PPC_ADMA_INIT_MEMREG;
> - ret = -EBUSY;
> - goto out;
> - }
> -
> /* create a device */
> adev = kzalloc_obj(*adev);
> if (!adev) {
> initcode = PPC_ADMA_INIT_ALLOC;
> ret = -ENOMEM;
> - goto err_adev_alloc;
> + goto out;
> }
>
> adev->id = id;
> @@ -4081,10 +4062,10 @@ static int ppc440spe_adma_probe(struct platform_device *ofdev)
> dev_dbg(&ofdev->dev, "allocated descriptor pool virt 0x%p phys 0x%llx\n",
> adev->dma_desc_pool_virt, (u64)adev->dma_desc_pool);
>
> - regs = ioremap(res.start, resource_size(&res));
> - if (!regs) {
> - dev_err(&ofdev->dev, "failed to ioremap regs!\n");
> - ret = -ENOMEM;
> + regs = devm_platform_ioremap_resource(ofdev, 0);
> + if (IS_ERR(regs)) {
> + ret = PTR_ERR(regs);
> + initcode = PPC_ADMA_INIT_MEMRES;
> goto err_regs_alloc;
> }
>
> @@ -4121,7 +4102,7 @@ static int ppc440spe_adma_probe(struct platform_device *ofdev)
> if (!chan) {
> initcode = PPC_ADMA_INIT_CHANNEL;
> ret = -ENOMEM;
> - goto err_chan_alloc;
> + goto err_regs_alloc;
> }
>
> spin_lock_init(&chan->lock);
> @@ -4214,19 +4195,12 @@ static int ppc440spe_adma_probe(struct platform_device *ofdev)
> }
> err_page_alloc:
> kfree(chan);
> -err_chan_alloc:
> - if (adev->id == PPC440SPE_XOR_ID)
> - iounmap(adev->xor_reg);
> - else
> - iounmap(adev->dma_reg);
> err_regs_alloc:
> dma_free_coherent(&ofdev->dev, adev->pool_size,
> adev->dma_desc_pool_virt,
> adev->dma_desc_pool);
> err_dma_alloc:
> kfree(adev);
> -err_adev_alloc:
> - release_mem_region(res.start, resource_size(&res));
> out:
> if (id < PPC440SPE_ADMA_ENGINES_NUM)
> ppc440spe_adma_devices[id] = initcode;
> @@ -4240,8 +4214,6 @@ static int ppc440spe_adma_probe(struct platform_device *ofdev)
> static void ppc440spe_adma_remove(struct platform_device *ofdev)
> {
> struct ppc440spe_adma_device *adev = platform_get_drvdata(ofdev);
> - struct device_node *np = ofdev->dev.of_node;
> - struct resource res;
> struct dma_chan *chan, *_chan;
> struct ppc_dma_chan_ref *ref, *_ref;
> struct ppc440spe_adma_chan *ppc440spe_chan;
> @@ -4278,12 +4250,6 @@ static void ppc440spe_adma_remove(struct platform_device *ofdev)
>
> dma_free_coherent(adev->dev, adev->pool_size,
> adev->dma_desc_pool_virt, adev->dma_desc_pool);
> - if (adev->id == PPC440SPE_XOR_ID)
> - iounmap(adev->xor_reg);
> - else
> - iounmap(adev->dma_reg);
> - of_address_to_resource(np, 0, &res);
> - release_mem_region(res.start, resource_size(&res));
> kfree(adev);
> }
>
> --
> 2.55.0
>