Re: [PATCH v4 4/4] dmaengine: mediatek-cqdma: add dma mask for capability

[EastL]

On Thu, 2020-05-28 at 16:10 +0200, Matthias Brugger wrote:
> 
> On 28/05/2020 11:57, EastL wrote:
> > This patch add dma mask for capability.
> > 
> > Change-Id: I31f4622f9541d769702029532e5f5f185815dda2
> 
> No Change-Id in the commit message please.
> 
> > Signed-off-by: EastL <EastL.Lee@xxxxxxxxxxxx>
> > ---
> >  drivers/dma/mediatek/mtk-cqdma.c | 13 +++++++++++++
> >  1 file changed, 13 insertions(+)
> > 
> > diff --git a/drivers/dma/mediatek/mtk-cqdma.c b/drivers/dma/mediatek/mtk-cqdma.c
> > index bca7118..1805a76 100644
> > --- a/drivers/dma/mediatek/mtk-cqdma.c
> > +++ b/drivers/dma/mediatek/mtk-cqdma.c
> > @@ -117,6 +117,7 @@ struct mtk_cqdma_vchan {
> >   * @clk:                    The clock that device internal is using
> >   * @dma_requests:           The number of VCs the device supports to
> >   * @dma_channels:           The number of PCs the device supports to
> > + * @dma_mask:               A mask for DMA capability
> >   * @vc:                     The pointer to all available VCs
> >   * @pc:                     The pointer to all the underlying PCs
> >   */
> > @@ -126,6 +127,7 @@ struct mtk_cqdma_device {
> >  
> >  	u32 dma_requests;
> >  	u32 dma_channels;
> > +	u32 dma_mask;
> >  	struct mtk_cqdma_vchan *vc;
> >  	struct mtk_cqdma_pchan **pc;
> >  };
> > @@ -549,6 +551,7 @@ static void mtk_cqdma_hw_deinit(struct mtk_cqdma_device *cqdma)
> >  };
> >  MODULE_DEVICE_TABLE(of, mtk_cqdma_match);
> >  
> > +static u64 cqdma_dmamask;
> >  static int mtk_cqdma_probe(struct platform_device *pdev)
> >  {
> >  	struct mtk_cqdma_device *cqdma;
> > @@ -607,6 +610,16 @@ static int mtk_cqdma_probe(struct platform_device *pdev)
> >  		cqdma->dma_channels = MTK_CQDMA_NR_PCHANS;
> >  	}
> >  
> > +	if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,
> > +						      "dma-channel-mask",
> > +						      &cqdma->dma_mask)) {
> 
> I'd prefer:
> 
> if (pdev->dev.of_node)
>     ret = of_property_read_u32(pdev->dev.of_node,
>                                "dma-channel-mask",
>                                &cqdma->dma_mask))
> if (ret) {
>     dev_warn(&pdev->dev,
>              "Using 0 as missing dma-channel-mask
>               property\n");
>     cqdma->dma_mask = 0;
> }
> 
> > +		dev_info(&pdev->dev,
> > +			 "Using 0 as missing dma-channel-mask property\n");
> 
> dev_warn should be OK.
> 
> > +	} else {
> > +		cqdma_dmamask = DMA_BIT_MASK(cqdma->dma_mask);
> > +		pdev->dev.dma_mask = &cqdma_dmamask;
> 
> if (dma_set_mask(&pdev->dev,
>     DMA_BIT_MASK(cqdma->dma_mask)) {
>          /* error out */
> }
> 
OK, I'll fix it on next version.

> > +	}
> > +
> >  	cqdma->pc = devm_kcalloc(&pdev->dev, cqdma->dma_channels,
> >  				 sizeof(*cqdma->pc), GFP_KERNEL);
> >  	if (!cqdma->pc)
> >