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From:   Marco Felsch <m.felsch@pengutronix.de>
To:     davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        peppe.cavallaro@st.com, alexandre.torgue@foss.st.com,
        joabreu@synopsys.com, mcoquelin.stm32@gmail.com
Cc:     netdev@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de
Subject: [PATCH net-next 2/2] net: stmmac: platform: add support for phy-supply
Date:   Mon, 17 Jul 2023 18:43:07 +0200
Message-Id: <20230717164307.2868264-2-m.felsch@pengutronix.de>
In-Reply-To: <20230717164307.2868264-1-m.felsch@pengutronix.de>
References: <20230717164307.2868264-1-m.felsch@pengutronix.de>
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Add generic phy-supply handling support to control the phy regulator.
Use the common stmmac_platform code path so all drivers using
stmmac_probe_config_dt() and stmmac_pltfr_pm_ops can use it.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 .../ethernet/stmicro/stmmac/stmmac_platform.c | 51 +++++++++++++++++++
 include/linux/stmmac.h                        |  1 +
 2 files changed, 52 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index eb0b2898daa3d..6193d42b53fb7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -10,6 +10,7 @@
 
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
 #include <linux/module.h>
 #include <linux/io.h>
 #include <linux/of.h>
@@ -423,6 +424,15 @@ stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac)
 	if (plat->interface < 0)
 		plat->interface = plat->phy_interface;
 
+	/* Optional regulator for PHY */
+	plat->phy_regulator = devm_regulator_get_optional(&pdev->dev, "phy");
+	if (IS_ERR(plat->phy_regulator)) {
+		if (PTR_ERR(plat->phy_regulator) == -EPROBE_DEFER)
+			return ERR_CAST(plat->phy_regulator);
+		dev_info(&pdev->dev, "No regulator found\n");
+		plat->phy_regulator = NULL;
+	}
+
 	/* Some wrapper drivers still rely on phy_node. Let's save it while
 	 * they are not converted to phylink. */
 	plat->phy_node = of_parse_phandle(np, "phy-handle", 0);
@@ -659,6 +669,38 @@ void stmmac_remove_config_dt(struct platform_device *pdev,
 EXPORT_SYMBOL_GPL(stmmac_probe_config_dt);
 EXPORT_SYMBOL_GPL(stmmac_remove_config_dt);
 
+static int stmmac_phy_power(struct platform_device *pdev,
+			    struct plat_stmmacenet_data *plat,
+			    bool enable)
+{
+	struct regulator *regulator = plat->phy_regulator;
+	int ret = 0;
+
+	if (regulator) {
+		if (enable)
+			ret = regulator_enable(regulator);
+		else
+			regulator_disable(regulator);
+	}
+
+	if (ret)
+		dev_err(&pdev->dev, "Fail to enable regulator\n");
+
+	return ret;
+}
+
+static int stmmac_phy_power_on(struct platform_device *pdev,
+			       struct plat_stmmacenet_data *plat)
+{
+	return stmmac_phy_power(pdev, plat, true);
+}
+
+static void stmmac_phy_power_off(struct platform_device *pdev,
+				 struct plat_stmmacenet_data *plat)
+{
+	stmmac_phy_power(pdev, plat, false);
+}
+
 int stmmac_get_platform_resources(struct platform_device *pdev,
 				  struct stmmac_resources *stmmac_res)
 {
@@ -720,6 +762,8 @@ int stmmac_pltfr_remove(struct platform_device *pdev)
 
 	stmmac_remove_config_dt(pdev, plat);
 
+	stmmac_phy_power_off(pdev, plat);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(stmmac_pltfr_remove);
@@ -742,6 +786,8 @@ static int __maybe_unused stmmac_pltfr_suspend(struct device *dev)
 	if (priv->plat->exit)
 		priv->plat->exit(pdev, priv->plat->bsp_priv);
 
+	stmmac_phy_power_off(pdev, priv->plat);
+
 	return ret;
 }
 
@@ -757,6 +803,11 @@ static int __maybe_unused stmmac_pltfr_resume(struct device *dev)
 	struct net_device *ndev = dev_get_drvdata(dev);
 	struct stmmac_priv *priv = netdev_priv(ndev);
 	struct platform_device *pdev = to_platform_device(dev);
+	int ret;
+
+	ret = stmmac_phy_power_on(pdev, priv->plat);
+	if (ret)
+		return ret;
 
 	if (priv->plat->init)
 		priv->plat->init(pdev, priv->plat->bsp_priv);
diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index 225751a8fd8e3..456bab4a3b362 100644
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -209,6 +209,7 @@ struct plat_stmmacenet_data {
 	int phy_addr;
 	int interface;
 	phy_interface_t phy_interface;
+	struct regulator *phy_regulator;
 	struct stmmac_mdio_bus_data *mdio_bus_data;
 	struct device_node *phy_node;
 	struct device_node *phylink_node;
-- 
2.39.2