From: Josep Orga <jorga@somdevices.com>
Date: Thu, 2 May 2019 18:19:04 +0000 (+0200)
Subject: Function fec_enet_clk_enable() was disabling this line leaving the PHY
X-Git-Tag: C0P2-H0.0--20200415~25
X-Git-Url: https://git.somdevices.com/?a=commitdiff_plain;h=b3c74a7d693c9a5e555d23b07a6d2b0cc4a62eb8;p=linux.git

Function fec_enet_clk_enable() was disabling this line leaving the PHY
without a running clock. This makes the PHY lose its internal state
requiring a reset of the PHY to be reactivated.

This patch enables the clk_enet_out once at probe() so that it remains
enabled during all MDIO accesses.

References:	https://github.com/digi-embedded/linux/commit/fa3f9ab2d2650ba6b24f2ef62ddedbf971e56d07#diff-28c0935b4b5bf1738a0ee788d25a18ffR1952
		https://patchwork.ozlabs.org/patch/549391/

Signed-off-by: Josep Orga <jorga@somdevices.com>
---

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index eca54e5cb104..6ab85fdf32eb 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1925,11 +1925,6 @@ static int fec_enet_clk_enable(struct net_device *ndev, bool enable)
 	int ret;
 
 	if (enable) {
-		if (fep->clk_enet_out) {
-			ret = clk_prepare_enable(fep->clk_enet_out);
-			if (ret)
-				return ret;
-		}
 		if (fep->clk_ptp) {
 			mutex_lock(&fep->ptp_clk_mutex);
 			ret = clk_prepare_enable(fep->clk_ptp);
@@ -1952,8 +1947,6 @@ static int fec_enet_clk_enable(struct net_device *ndev, bool enable)
 				goto failed_clk_2x_txclk;
 		}
 	} else {
-		if (fep->clk_enet_out)
-			clk_disable_unprepare(fep->clk_enet_out);
 		if (fep->clk_ptp) {
 			mutex_lock(&fep->ptp_clk_mutex);
 			clk_disable_unprepare(fep->clk_ptp);
@@ -1975,8 +1968,7 @@ failed_clk_ref:
 	if (fep->clk_ptp)
 		clk_disable_unprepare(fep->clk_ptp);
 failed_clk_ptp:
-	if (fep->clk_enet_out)
-		clk_disable_unprepare(fep->clk_enet_out);
+	clk_disable_unprepare(fep->clk_ipg);
 
 	return ret;
 }
@@ -3701,6 +3693,11 @@ fec_probe(struct platform_device *pdev)
 	fep->clk_enet_out = devm_clk_get(&pdev->dev, "enet_out");
 	if (IS_ERR(fep->clk_enet_out))
 		fep->clk_enet_out = NULL;
+	if (fep->clk_enet_out) {
+		ret = clk_prepare_enable(fep->clk_enet_out);
+		if (ret)
+			goto failed_clk_ipg;
+	}
 
 	fep->ptp_clk_on = false;
 	mutex_init(&fep->ptp_clk_mutex);
@@ -3865,6 +3862,8 @@ fec_drv_remove(struct platform_device *pdev)
 	fec_ptp_stop(pdev);
 	unregister_netdev(ndev);
 	fec_enet_mii_remove(fep);
+	if (fep->clk_enet_out)
+		clk_disable_unprepare(fep->clk_enet_out);
 	if (fep->reg_phy)
 		regulator_disable(fep->reg_phy);
 	if (of_phy_is_fixed_link(np))