netdev - [PATCH net-next 1/3] net: phy: realtek: eliminate priv->phycr2 variable

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20251106111003.37023-2-vladimir.oltean@nxp.com>
Date: Thu,  6 Nov 2025 13:10:01 +0200
From: Vladimir Oltean <vladimir.oltean@....com>
To: netdev@...r.kernel.org
Cc: Andrew Lunn <andrew@...n.ch>,
	Heiner Kallweit <hkallweit1@...il.com>,
	Russell King <linux@...linux.org.uk>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>,
	Marek Vasut <marex@...x.de>,
	Wei Fang <wei.fang@....com>,
	Clark Wang <xiaoning.wang@....com>
Subject: [PATCH net-next 1/3] net: phy: realtek: eliminate priv->phycr2 variable

The RTL8211F(D)(I)-VD-CG PHY also has support for disabling the CLKOUT,
and we'd like to introduce the "realtek,clkout-disable" property for
that.

But it isn't done through the PHYCR2 register, and it becomes awkward to
have the driver pretend that it is. So just replace the machine-level
"u16 phycr2" variable with a logical "bool disable_clk_out", which
scales better to the other PHY as well.

The change is a complete functional equivalent. Before, if the device
tree property was absent, priv->phycr2 would contain the RTL8211F_CLKOUT_EN
bit as read from hardware. Now, we don't save priv->phycr2, but we just
don't call phy_modify_paged() on it. Also, we can simply call
phy_modify_paged() with the "set" argument to 0.

Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
---
 drivers/net/phy/realtek/realtek_main.c | 31 ++++++++++++++------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
index 417f9a88aab6..45b53660018a 100644
--- a/drivers/net/phy/realtek/realtek_main.c
+++ b/drivers/net/phy/realtek/realtek_main.c
@@ -194,8 +194,8 @@ MODULE_LICENSE("GPL");
 
 struct rtl821x_priv {
 	u16 phycr1;
-	u16 phycr2;
 	bool has_phycr2;
+	bool disable_clk_out;
 	struct clk *clk;
 	/* rtl8211f */
 	u16 iner;
@@ -266,15 +266,8 @@ static int rtl821x_probe(struct phy_device *phydev)
 		priv->phycr1 |= RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_XTAL_OFF;
 
 	priv->has_phycr2 = !(phy_id == RTL_8211FVD_PHYID);
-	if (priv->has_phycr2) {
-		ret = phy_read_paged(phydev, RTL8211F_PHYCR_PAGE, RTL8211F_PHYCR2);
-		if (ret < 0)
-			return ret;
-
-		priv->phycr2 = ret & RTL8211F_CLKOUT_EN;
-		if (of_property_read_bool(dev->of_node, "realtek,clkout-disable"))
-			priv->phycr2 &= ~RTL8211F_CLKOUT_EN;
-	}
+	priv->disable_clk_out = of_property_read_bool(dev->of_node,
+						      "realtek,clkout-disable");
 
 	phydev->priv = priv;
 
@@ -587,6 +580,18 @@ static int rtl8211c_config_init(struct phy_device *phydev)
 			    CTL1000_ENABLE_MASTER | CTL1000_AS_MASTER);
 }
 
+static int rtl8211f_disable_clk_out(struct phy_device *phydev)
+{
+	struct rtl821x_priv *priv = phydev->priv;
+
+	/* The value is preserved if the device tree property is absent */
+	if (!priv->disable_clk_out)
+		return 0;
+
+	return phy_modify_paged(phydev, RTL8211F_PHYCR_PAGE,
+				RTL8211F_PHYCR2, RTL8211F_CLKOUT_EN, 0);
+}
+
 static int rtl8211f_config_init(struct phy_device *phydev)
 {
 	struct rtl821x_priv *priv = phydev->priv;
@@ -669,10 +674,8 @@ static int rtl8211f_config_init(struct phy_device *phydev)
 	if (ret)
 		return ret;
 
-	ret = phy_modify_paged(phydev, RTL8211F_PHYCR_PAGE,
-			       RTL8211F_PHYCR2, RTL8211F_CLKOUT_EN,
-			       priv->phycr2);
-	if (ret < 0) {
+	ret = rtl8211f_disable_clk_out(phydev);
+	if (ret) {
 		dev_err(dev, "clkout configuration failed: %pe\n",
 			ERR_PTR(ret));
 		return ret;
-- 
2.34.1