Re: [PATCH 3/4] tsi108_eth: use dma API properly

[Andy Shevchenko]

On Wed, Jan 10, 2018 at 8:03 PM, Christoph Hellwig <hch@xxxxxx> wrote:
> We need to pass a struct device to the dma API, even if some
> architectures still support that for legacy reasons, and should not mix
> it with the old PCI dma API.
>
> Note that the driver also seems to never actually unmap its dma mappings,
> but to fix that we'll need someone more familar with the driver.

> +       struct platform_device *pdev;

Do you really need platform_defice reference?

Perhaps

struct device *hdev; // hardware device


data->hdev = &pdev->dev;

Another idea

dev->dev.parent = &pdev->dev;

No new member needed.

>  };
>
>  /* Structure for a device driver */
> @@ -703,17 +705,18 @@ static int tsi108_send_packet(struct sk_buff * skb, struct net_device *dev)
>                 data->txskbs[tx] = skb;
>
>                 if (i == 0) {
> -                       data->txring[tx].buf0 = dma_map_single(NULL, skb->data,
> -                                       skb_headlen(skb), DMA_TO_DEVICE);
> +                       data->txring[tx].buf0 = dma_map_single(&data->pdev->dev,
> +                                       skb->data, skb_headlen(skb),
> +                                       DMA_TO_DEVICE);
>                         data->txring[tx].len = skb_headlen(skb);
>                         misc |= TSI108_TX_SOF;
>                 } else {
>                         const skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
>
> -                       data->txring[tx].buf0 = skb_frag_dma_map(NULL, frag,
> -                                                                0,
> -                                                                skb_frag_size(frag),
> -                                                                DMA_TO_DEVICE);
> +                       data->txring[tx].buf0 =
> +                               skb_frag_dma_map(&data->pdev->dev, frag,
> +                                               0, skb_frag_size(frag),
> +                                               DMA_TO_DEVICE);
>                         data->txring[tx].len = skb_frag_size(frag);
>                 }
>
> @@ -808,9 +811,9 @@ static int tsi108_refill_rx(struct net_device *dev, int budget)
>                 if (!skb)
>                         break;
>
> -               data->rxring[rx].buf0 = dma_map_single(NULL, skb->data,
> -                                                       TSI108_RX_SKB_SIZE,
> -                                                       DMA_FROM_DEVICE);
> +               data->rxring[rx].buf0 = dma_map_single(&data->pdev->dev,
> +                               skb->data, TSI108_RX_SKB_SIZE,
> +                               DMA_FROM_DEVICE);
>
>                 /* Sometimes the hardware sets blen to zero after packet
>                  * reception, even though the manual says that it's only ever
> @@ -1308,15 +1311,15 @@ static int tsi108_open(struct net_device *dev)
>                        data->id, dev->irq, dev->name);
>         }
>
> -       data->rxring = dma_zalloc_coherent(NULL, rxring_size, &data->rxdma,
> -                                          GFP_KERNEL);
> +       data->rxring = dma_zalloc_coherent(&data->pdev->dev, rxring_size,
> +                       &data->rxdma, GFP_KERNEL);
>         if (!data->rxring)
>                 return -ENOMEM;
>
> -       data->txring = dma_zalloc_coherent(NULL, txring_size, &data->txdma,
> -                                          GFP_KERNEL);
> +       data->txring = dma_zalloc_coherent(&data->pdev->dev, txring_size,
> +                       &data->txdma, GFP_KERNEL);
>         if (!data->txring) {
> -               pci_free_consistent(NULL, rxring_size, data->rxring,
> +               dma_free_coherent(&data->pdev->dev, rxring_size, data->rxring,
>                                     data->rxdma);
>                 return -ENOMEM;
>         }
> @@ -1428,10 +1431,10 @@ static int tsi108_close(struct net_device *dev)
>                 dev_kfree_skb(skb);
>         }
>
> -       dma_free_coherent(0,
> +       dma_free_coherent(&data->pdev->dev,
>                             TSI108_RXRING_LEN * sizeof(rx_desc),
>                             data->rxring, data->rxdma);
> -       dma_free_coherent(0,
> +       dma_free_coherent(&data->pdev->dev,
>                             TSI108_TXRING_LEN * sizeof(tx_desc),
>                             data->txring, data->txdma);
>
> @@ -1576,6 +1579,7 @@ tsi108_init_one(struct platform_device *pdev)
>         printk("tsi108_eth%d: probe...\n", pdev->id);
>         data = netdev_priv(dev);
>         data->dev = dev;
> +       data->pdev = pdev;
>
>         pr_debug("tsi108_eth%d:regs:phyresgs:phy:irq_num=0x%x:0x%x:0x%x:0x%x\n",
>                         pdev->id, einfo->regs, einfo->phyregs,
> --
> 2.14.2
>



-- 
With Best Regards,
Andy Shevchenko