net: fec: add phy_reset_after_clk_enable() support

Hello Richard Leitner,

This is a semi-automatic email about new static checker warnings.

The patch 1b0a83ac04e3: "net: fec: add phy_reset_after_clk_enable() support" from Dec 11, 2017, leads to the following Smatch complaint:

    drivers/net/ethernet/freescale/fec_main.c:2895 fec_enet_open()
    error: we previously assumed 'ndev->phydev' could be null (see line 2864)

drivers/net/ethernet/freescale/fec_main.c
2863 */
2864 if (ndev->phydev && ndev->phydev->drv)

                    ^^^^^^^^^^^^

Patch introduced a new check.

2865 reset_again = false;
2866 else
2867 reset_again = true;
2868
2869 /* I should reset the ring buffers here, but I don't yet know
2870 * a simple way to do that.
2871 */
2872
2873 ret = fec_enet_alloc_buffers(ndev);
2874 if (ret)
2875 goto err_enet_alloc;
2876
2877 /* Init MAC prior to mii bus probe */
2878 fec_restart(ndev);
2879
2880 /* Probe and connect to PHY when open the interface */
2881 ret = fec_enet_mii_probe(ndev);
2882 if (ret)
2883 goto err_enet_mii_probe;
2884
2885 /* Call phy_reset_after_clk_enable() again if it failed during
2886 * phy_reset_after_clk_enable() before because the PHY wasn't probed.
2887 */
2888 if (reset_again)
2889 phy_reset_after_clk_enable(ndev->phydev);
2890
2891 if (fep->quirks & FEC_QUIRK_ERR006687)
2892 imx6q_cpuidle_fec_irqs_used();
2893
2894 napi_enable(&fep->napi);

  2895		phy_start(ndev->phydev);
                          ^^^^^^^^^^^^

Unchecked dereference inside function.

  2896		netif_tx_start_all_queues(ndev);
  2897	

regards,
dan carpenter