[PATCH 4.14 086/115] net: fec: manage ahb clock in runtime pm

[Greg Kroah-Hartman]

[ Upstream commit d7c3a206e6338e4ccdf030719dec028e26a521d5 ]

Some SOC like i.MX6SX clock have some limits:
- ahb clock should be disabled before ipg.
- ahb and ipg clocks are required for MAC MII bus.
So, move the ahb clock to runtime management together with
ipg clock.

Signed-off-by: Fugang Duan <fugang.d...@nxp.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
---
 drivers/net/ethernet/freescale/fec_main.c | 30 ++++++++++++++++-------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c 
b/drivers/net/ethernet/freescale/fec_main.c
index ce55c8f7f33a4..ad3aabc39cc24 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1851,13 +1851,9 @@ static int fec_enet_clk_enable(struct net_device *ndev, 
bool enable)
        int ret;
 
        if (enable) {
-               ret = clk_prepare_enable(fep->clk_ahb);
-               if (ret)
-                       return ret;
-
                ret = clk_prepare_enable(fep->clk_enet_out);
                if (ret)
-                       goto failed_clk_enet_out;
+                       return ret;
 
                if (fep->clk_ptp) {
                        mutex_lock(&fep->ptp_clk_mutex);
@@ -1875,7 +1871,6 @@ static int fec_enet_clk_enable(struct net_device *ndev, 
bool enable)
                if (ret)
                        goto failed_clk_ref;
        } else {
-               clk_disable_unprepare(fep->clk_ahb);
                clk_disable_unprepare(fep->clk_enet_out);
                if (fep->clk_ptp) {
                        mutex_lock(&fep->ptp_clk_mutex);
@@ -1894,8 +1889,6 @@ static int fec_enet_clk_enable(struct net_device *ndev, 
bool enable)
 failed_clk_ptp:
        if (fep->clk_enet_out)
                clk_disable_unprepare(fep->clk_enet_out);
-failed_clk_enet_out:
-               clk_disable_unprepare(fep->clk_ahb);
 
        return ret;
 }
@@ -3455,6 +3448,9 @@ fec_probe(struct platform_device *pdev)
        ret = clk_prepare_enable(fep->clk_ipg);
        if (ret)
                goto failed_clk_ipg;
+       ret = clk_prepare_enable(fep->clk_ahb);
+       if (ret)
+               goto failed_clk_ahb;
 
        fep->reg_phy = devm_regulator_get(&pdev->dev, "phy");
        if (!IS_ERR(fep->reg_phy)) {
@@ -3546,6 +3542,9 @@ fec_probe(struct platform_device *pdev)
        pm_runtime_put(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
 failed_regulator:
+       clk_disable_unprepare(fep->clk_ahb);
+failed_clk_ahb:
+       clk_disable_unprepare(fep->clk_ipg);
 failed_clk_ipg:
        fec_enet_clk_enable(ndev, false);
 failed_clk:
@@ -3669,6 +3668,7 @@ static int __maybe_unused fec_runtime_suspend(struct 
device *dev)
        struct net_device *ndev = dev_get_drvdata(dev);
        struct fec_enet_private *fep = netdev_priv(ndev);
 
+       clk_disable_unprepare(fep->clk_ahb);
        clk_disable_unprepare(fep->clk_ipg);
 
        return 0;
@@ -3678,8 +3678,20 @@ static int __maybe_unused fec_runtime_resume(struct 
device *dev)
 {
        struct net_device *ndev = dev_get_drvdata(dev);
        struct fec_enet_private *fep = netdev_priv(ndev);
+       int ret;
 
-       return clk_prepare_enable(fep->clk_ipg);
+       ret = clk_prepare_enable(fep->clk_ahb);
+       if (ret)
+               return ret;
+       ret = clk_prepare_enable(fep->clk_ipg);
+       if (ret)
+               goto failed_clk_ipg;
+
+       return 0;
+
+failed_clk_ipg:
+       clk_disable_unprepare(fep->clk_ahb);
+       return ret;
 }
 
 static const struct dev_pm_ops fec_pm_ops = {
-- 
2.20.1