ENGR00299593-4 net:fec: return -EPROBE_DEFER when phy regulator isn't initialized

On i.mx6sx-17x17-arm2 board, fec needs to supply phy via max7322 extention gpio.
When fec probe, the phy regulator doesn't complete initilization. The fec_probe
needs to return  -EPROBE_DEFER and kernel will retry fec_probe after a delay.

Signed-off-by: Luwei Zhou <b45643@freescale.com>

1 files changed, 24 insertions, 15 deletions

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index cb3e5fec4897..e71e5cf1838c 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -2582,6 +2582,7 @@ fec_probe(struct platform_device *pdev)
         static int dev_id;
         int num_tx_qs = 1;
         int num_rx_qs = 1;
+        struct regulator *phy_reg = NULL;
 
         of_id = of_match_device(fec_dt_ids, &pdev->dev);
         if (of_id)
@@ -2591,6 +2592,26 @@ fec_probe(struct platform_device *pdev)
         if (!r)
                 return -ENXIO;
 
+        phy_reg = devm_regulator_get(&pdev->dev, "phy");
+
+        if (!IS_ERR(phy_reg)) {
+                ret = regulator_enable(phy_reg);
+                if (ret) {
+                        dev_err(&pdev->dev,
+                                "Failed to enable phy regulator: %d\n", ret);
+                        return ret;
+                }
+        } else if (phy_reg == ERR_PTR(-EPROBE_DEFER)) {
+                /* Return -EPROBE_DEFER when the regulator is not
+                 * sufficient initialized. When -EPROBE_DEFER is
+                 * returned in fec_probe, the kernel will retry
+                 * fec_probe after suitalbe delay.
+                 */
+                return -EPROBE_DEFER;
+        } else {
+                phy_reg = NULL;
+        }
+
         if (pdev->id_entry &&
             (pdev->id_entry->driver_data & FEC_QUIRK_HAS_AVB)) {
                 ret = fec_enet_get_queue_num(pdev, &num_tx_qs, &num_rx_qs);
@@ -2608,6 +2629,7 @@ fec_probe(struct platform_device *pdev)
         /* setup board info structure */
         fep = netdev_priv(ndev);
 
+        fep->reg_phy = phy_reg;
         fep->num_rx_queues = num_rx_qs;
         fep->num_tx_queues = num_tx_qs;
         netif_set_real_num_rx_queues(ndev, num_rx_qs);
@@ -2681,18 +2703,6 @@ fec_probe(struct platform_device *pdev)
 
         fec_enet_clk_enable(ndev, true);
 
-        fep->reg_phy = devm_regulator_get(&pdev->dev, "phy");
-        if (!IS_ERR(fep->reg_phy)) {
-                ret = regulator_enable(fep->reg_phy);
-                if (ret) {
-                        dev_err(&pdev->dev,
-                                "Failed to enable phy regulator: %d\n", ret);
-                        goto failed_regulator;
-                }
-        } else {
-                fep->reg_phy = NULL;
-        }
-
         if (fep->bufdesc_ex)
                 fec_ptp_init(pdev);
 
@@ -2750,13 +2760,12 @@ failed_irq:
                         free_irq(irq, ndev);
         }
 failed_init:
-        if (fep->reg_phy)
-                regulator_disable(fep->reg_phy);
-failed_regulator:
         fec_enet_clk_enable(ndev, false);
 failed_clk:
 failed_ioremap:
         free_netdev(ndev);
+        if (fep->reg_phy)
+                regulator_disable(fep->reg_phy);
 
         return ret;
 }