# Re: \[PATCH 4/6\] dpaa2-eth: retry the probe when the MAC is not yet discovered on the bus

- From: Andrew Lunn \<andrew@lunn.ch\>
- Date: 2021-01-07 21:25:39 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/01/11191983
- Thread: https://ratatoskr.run/netdev/2021/01/11191894/t.md

```text
On Thu, Jan 07, 2021 at 05:36:36PM +0200, Ioana Ciornei wrote:
> From: Ioana Ciornei <ioana.ciornei@nxp.com>
> 
> The fsl_mc_get_endpoint() function now returns -EPROBE_DEFER when the
> dpmac device was not yet discovered by the fsl-mc bus. When this
> happens, pass the error code up so that we can retry the probe at a
> later time.
> 
> Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
> ---
>  drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> index f3f53e36aa00..3297e390476b 100644
> --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> @@ -4042,6 +4042,10 @@ static int dpaa2_eth_connect_mac(struct dpaa2_eth_priv *priv)
>  
>  	dpni_dev = to_fsl_mc_device(priv->net_dev->dev.parent);
>  	dpmac_dev = fsl_mc_get_endpoint(dpni_dev);
> +
> +	if (PTR_ERR(dpmac_dev) == -EPROBE_DEFER)
> +		return PTR_ERR(dpmac_dev);
> +
>  	if (IS_ERR_OR_NULL(dpmac_dev) || dpmac_dev->dev.type != &fsl_mc_bus_dpmac_type)

Hi Ioana

Given the previous change, i don't think dpmac_dev can be NULL, so you
can change this to IS_ERR(). IS_ERR_OR_NULL() often triggers extra
review work because it is easy to get it wrong, so removing it is nice.

       Andrew
```