[PATCH net-next v2 07/21] net: ravb: Move reference clock enable/disable on runtime PM APIs

[Claudiu]

From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>

Reference clock could be or not part of the power domain. If it is part of
the power domain, the power domain takes care of propertly setting it. In
case it is not part of the power domain and full runtime PM support is
available in driver the clock will not be propertly disabled/enabled at
runtime. For this, keep the prepare/unprepare operations in the driver's
probe()/remove() functions and move the enable/disable in runtime PM
functions.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
---

Changes in v2:
- this patch is new and follows the recommendations proposed in the
  discussion of patch 08/13 ("net: ravb: Rely on PM domain to enable refclk")
  from v2

 drivers/net/ethernet/renesas/ravb_main.c | 88 +++++++++++++-----------
 1 file changed, 46 insertions(+), 42 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 9a618d8dbfcd..83691a0f0cc2 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2664,11 +2664,6 @@ static int ravb_probe(struct platform_device *pdev)
 	if (error)
 		goto out_free_netdev;
 
-	pm_runtime_enable(&pdev->dev);
-	error = pm_runtime_resume_and_get(&pdev->dev);
-	if (error < 0)
-		goto out_rpm_disable;
-
 	if (info->multi_irqs) {
 		if (info->err_mgmt_irqs)
 			irq = platform_get_irq_byname(pdev, "dia");
@@ -2679,7 +2674,7 @@ static int ravb_probe(struct platform_device *pdev)
 	}
 	if (irq < 0) {
 		error = irq;
-		goto out_release;
+		goto out_reset_assert;
 	}
 	ndev->irq = irq;
 
@@ -2697,10 +2692,23 @@ static int ravb_probe(struct platform_device *pdev)
 		priv->num_rx_ring[RAVB_NC] = NC_RX_RING_SIZE;
 	}
 
+	priv->refclk = devm_clk_get_optional(&pdev->dev, "refclk");
+	if (IS_ERR(priv->refclk)) {
+		error = PTR_ERR(priv->refclk);
+		goto out_reset_assert;
+	}
+	clk_prepare(priv->refclk);
+
+	platform_set_drvdata(pdev, ndev);
+	pm_runtime_enable(&pdev->dev);
+	error = pm_runtime_resume_and_get(&pdev->dev);
+	if (error < 0)
+		goto out_rpm_disable;
+
 	priv->addr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 	if (IS_ERR(priv->addr)) {
 		error = PTR_ERR(priv->addr);
-		goto out_release;
+		goto out_rpm_put;
 	}
 
 	/* The Ether-specific entries in the device structure. */
@@ -2711,7 +2719,7 @@ static int ravb_probe(struct platform_device *pdev)
 
 	error = of_get_phy_mode(np, &priv->phy_interface);
 	if (error && error != -ENODEV)
-		goto out_release;
+		goto out_rpm_put;
 
 	priv->no_avb_link = of_property_read_bool(np, "renesas,no-ether-link");
 	priv->avb_link_active_low =
@@ -2724,14 +2732,14 @@ static int ravb_probe(struct platform_device *pdev)
 			irq = platform_get_irq_byname(pdev, "ch24");
 		if (irq < 0) {
 			error = irq;
-			goto out_release;
+			goto out_rpm_put;
 		}
 		priv->emac_irq = irq;
 		for (i = 0; i < NUM_RX_QUEUE; i++) {
 			irq = platform_get_irq_byname(pdev, ravb_rx_irqs[i]);
 			if (irq < 0) {
 				error = irq;
-				goto out_release;
+				goto out_rpm_put;
 			}
 			priv->rx_irqs[i] = irq;
 		}
@@ -2739,7 +2747,7 @@ static int ravb_probe(struct platform_device *pdev)
 			irq = platform_get_irq_byname(pdev, ravb_tx_irqs[i]);
 			if (irq < 0) {
 				error = irq;
-				goto out_release;
+				goto out_rpm_put;
 			}
 			priv->tx_irqs[i] = irq;
 		}
@@ -2748,14 +2756,14 @@ static int ravb_probe(struct platform_device *pdev)
 			irq = platform_get_irq_byname(pdev, "err_a");
 			if (irq < 0) {
 				error = irq;
-				goto out_release;
+				goto out_rpm_put;
 			}
 			priv->erra_irq = irq;
 
 			irq = platform_get_irq_byname(pdev, "mgmt_a");
 			if (irq < 0) {
 				error = irq;
-				goto out_release;
+				goto out_rpm_put;
 			}
 			priv->mgmta_irq = irq;
 		}
@@ -2764,21 +2772,14 @@ static int ravb_probe(struct platform_device *pdev)
 	priv->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(priv->clk)) {
 		error = PTR_ERR(priv->clk);
-		goto out_release;
+		goto out_rpm_put;
 	}
 
-	priv->refclk = devm_clk_get_optional(&pdev->dev, "refclk");
-	if (IS_ERR(priv->refclk)) {
-		error = PTR_ERR(priv->refclk);
-		goto out_release;
-	}
-	clk_prepare_enable(priv->refclk);
-
 	if (info->gptp_ref_clk) {
 		priv->gptp_clk = devm_clk_get(&pdev->dev, "gptp");
 		if (IS_ERR(priv->gptp_clk)) {
 			error = PTR_ERR(priv->gptp_clk);
-			goto out_disable_refclk;
+			goto out_rpm_put;
 		}
 	}
 
@@ -2799,20 +2800,20 @@ static int ravb_probe(struct platform_device *pdev)
 	/* Set AVB config mode */
 	error = ravb_set_config_mode(ndev);
 	if (error)
-		goto out_disable_refclk;
+		goto out_rpm_put;
 
 	if (info->gptp || info->ccc_gac) {
 		/* Set GTI value */
 		error = ravb_set_gti(ndev);
 		if (error)
-			goto out_disable_refclk;
+			goto out_rpm_put;
 
 		/* Request GTI loading */
 		ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);
 		/* Check completion status. */
 		error = ravb_wait(ndev, GCCR, GCCR_LTI, 0);
 		if (error)
-			goto out_disable_refclk;
+			goto out_rpm_put;
 	}
 
 	if (info->internal_delay) {
@@ -2829,7 +2830,7 @@ static int ravb_probe(struct platform_device *pdev)
 			"Cannot allocate desc base address table (size %d bytes)\n",
 			priv->desc_bat_size);
 		error = -ENOMEM;
-		goto out_disable_refclk;
+		goto out_rpm_put;
 	}
 	for (q = RAVB_BE; q < DBAT_ENTRY_NUM; q++)
 		priv->desc_bat[q].die_dt = DT_EOS;
@@ -2875,8 +2876,6 @@ static int ravb_probe(struct platform_device *pdev)
 	netdev_info(ndev, "Base address at %#x, %pM, IRQ %d.\n",
 		    (u32)ndev->base_addr, ndev->dev_addr, ndev->irq);
 
-	platform_set_drvdata(pdev, ndev);
-
 	return 0;
 
 out_napi_del:
@@ -2892,12 +2891,12 @@ static int ravb_probe(struct platform_device *pdev)
 	/* Stop PTP Clock driver */
 	if (info->ccc_gac)
 		ravb_ptp_stop(ndev);
-out_disable_refclk:
-	clk_disable_unprepare(priv->refclk);
-out_release:
+out_rpm_put:
 	pm_runtime_put(&pdev->dev);
 out_rpm_disable:
 	pm_runtime_disable(&pdev->dev);
+	clk_unprepare(priv->refclk);
+out_reset_assert:
 	reset_control_assert(rstc);
 out_free_netdev:
 	free_netdev(ndev);
@@ -2929,10 +2928,9 @@ static void ravb_remove(struct platform_device *pdev)
 	if (error)
 		netdev_err(ndev, "Failed to reset ndev\n");
 
-	clk_disable_unprepare(priv->refclk);
-
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
+	clk_unprepare(priv->refclk);
 	reset_control_assert(priv->rstc);
 	free_netdev(ndev);
 	platform_set_drvdata(pdev, NULL);
@@ -3071,21 +3069,27 @@ static int ravb_resume(struct device *dev)
 	return ret;
 }
 
-static int ravb_runtime_nop(struct device *dev)
+static int ravb_runtime_suspend(struct device *dev)
 {
-	/* Runtime PM callback shared between ->runtime_suspend()
-	 * and ->runtime_resume(). Simply returns success.
-	 *
-	 * This driver re-initializes all registers after
-	 * pm_runtime_get_sync() anyway so there is no need
-	 * to save and restore registers here.
-	 */
+	struct net_device *ndev = dev_get_drvdata(dev);
+	struct ravb_private *priv = netdev_priv(ndev);
+
+	clk_disable(priv->refclk);
+
 	return 0;
 }
 
+static int ravb_runtime_resume(struct device *dev)
+{
+	struct net_device *ndev = dev_get_drvdata(dev);
+	struct ravb_private *priv = netdev_priv(ndev);
+
+	return clk_enable(priv->refclk);
+}
+
 static const struct dev_pm_ops ravb_dev_pm_ops = {
 	SYSTEM_SLEEP_PM_OPS(ravb_suspend, ravb_resume)
-	RUNTIME_PM_OPS(ravb_runtime_nop, ravb_runtime_nop, NULL)
+	RUNTIME_PM_OPS(ravb_runtime_suspend, ravb_runtime_resume, NULL)
 };
 
 static struct platform_driver ravb_driver = {
-- 
2.39.2