Subject: [PATCH net-next 7/7] net: phy: convert read-modify-write to phy_modify()

From: Russell King <[email-masked]>
Date: Fri, 29 Dec 2017 12:31:20 +0000

Convert read-modify-write sequences in at803x, Marvell and core phylib
to use phy_modify() to ensure safety.

Signed-off-by: Russell King <[email-masked]>
---
 drivers/net/phy/at803x.c     | 20 +++--------
 drivers/net/phy/marvell.c    | 82 ++++++++++++++++----------------------------
 drivers/net/phy/phy_device.c | 50 +++++----------------------
 3 files changed, 43 insertions(+), 109 deletions(-)

diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index e911e4990b20..e86c1b8b1b51 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -216,34 +216,22 @@ static int at803x_suspend(struct phy_device *phydev)
 	int value;
 	int wol_enabled;
 
-	mutex_lock(&phydev->lock);
-
 	value = phy_read(phydev, AT803X_INTR_ENABLE);
 	wol_enabled = value & AT803X_INTR_ENABLE_WOL;
 
-	value = phy_read(phydev, MII_BMCR);
-
 	if (wol_enabled)
-		value |= BMCR_ISOLATE;
+		value = BMCR_ISOLATE;
 	else
-		value |= BMCR_PDOWN;
+		value = BMCR_PDOWN;
 
-	phy_write(phydev, MII_BMCR, value);
-
-	mutex_unlock(&phydev->lock);
+	phy_modify(phydev, MII_BMCR, 0, value);
 
 	return 0;
 }
 
 static int at803x_resume(struct phy_device *phydev)
 {
-	int value;
-
-	value = phy_read(phydev, MII_BMCR);
-	value &= ~(BMCR_PDOWN | BMCR_ISOLATE);
-	phy_write(phydev, MII_BMCR, value);
-
-	return 0;
+	return phy_modify(phydev, MII_BMCR, ~(BMCR_PDOWN | BMCR_ISOLATE), 0);
 }
 
 static int at803x_probe(struct phy_device *phydev)
diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index 1cb84064d658..6129ab1000f9 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -664,19 +664,14 @@ static int m88e1116r_config_init(struct phy_device *phydev)
 
 static int m88e3016_config_init(struct phy_device *phydev)
 {
-	int reg;
+	int ret;
 
 	/* Enable Scrambler and Auto-Crossover */
-	reg = phy_read(phydev, MII_88E3016_PHY_SPEC_CTRL);
-	if (reg < 0)
-		return reg;
-
-	reg &= ~MII_88E3016_DISABLE_SCRAMBLER;
-	reg |= MII_88E3016_AUTO_MDIX_CROSSOVER;
-
-	reg = phy_write(phydev, MII_88E3016_PHY_SPEC_CTRL, reg);
-	if (reg < 0)
-		return reg;
+	ret = phy_modify(phydev, MII_88E3016_PHY_SPEC_CTRL,
+			 ~MII_88E3016_DISABLE_SCRAMBLER,
+			 MII_88E3016_AUTO_MDIX_CROSSOVER);
+	if (ret < 0)
+		return ret;
 
 	return marvell_config_init(phydev);
 }
@@ -685,42 +680,34 @@ static int m88e1111_config_init_hwcfg_mode(struct phy_device *phydev,
 					   u16 mode,
 					   int fibre_copper_auto)
 {
-	int temp;
-
-	temp = phy_read(phydev, MII_M1111_PHY_EXT_SR);
-	if (temp < 0)
-		return temp;
-
-	temp &= ~(MII_M1111_HWCFG_MODE_MASK |
-		  MII_M1111_HWCFG_FIBER_COPPER_AUTO |
-		  MII_M1111_HWCFG_FIBER_COPPER_RES);
-	temp |= mode;
-
 	if (fibre_copper_auto)
-		temp |= MII_M1111_HWCFG_FIBER_COPPER_AUTO;
+		mode |= MII_M1111_HWCFG_FIBER_COPPER_AUTO;
 
-	return phy_write(phydev, MII_M1111_PHY_EXT_SR, temp);
+	return phy_modify(phydev, MII_M1111_PHY_EXT_SR,
+			  (u16)~(MII_M1111_HWCFG_MODE_MASK |
+				 MII_M1111_HWCFG_FIBER_COPPER_AUTO |
+				 MII_M1111_HWCFG_FIBER_COPPER_RES),
+			  mode);
 }
 
 static int m88e1111_config_init_rgmii_delays(struct phy_device *phydev)
 {
-	int temp;
-
-	temp = phy_read(phydev, MII_M1111_PHY_EXT_CR);
-	if (temp < 0)
-		return temp;
+	int delay;
 
 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID) {
-		temp |= (MII_M1111_RGMII_RX_DELAY | MII_M1111_RGMII_TX_DELAY);
+		delay = MII_M1111_RGMII_RX_DELAY | MII_M1111_RGMII_TX_DELAY;
 	} else if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) {
-		temp &= ~MII_M1111_RGMII_TX_DELAY;
-		temp |= MII_M1111_RGMII_RX_DELAY;
+		delay = MII_M1111_RGMII_RX_DELAY;
 	} else if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) {
-		temp &= ~MII_M1111_RGMII_RX_DELAY;
-		temp |= MII_M1111_RGMII_TX_DELAY;
+		delay = MII_M1111_RGMII_TX_DELAY;
+	} else {
+		delay = 0;
 	}
 
-	return phy_write(phydev, MII_M1111_PHY_EXT_CR, temp);
+	return phy_modify(phydev, MII_M1111_PHY_EXT_CR,
+			  (u16)~(MII_M1111_RGMII_RX_DELAY |
+				 MII_M1111_RGMII_TX_DELAY),
+			  delay);
 }
 
 static int m88e1111_config_init_rgmii(struct phy_device *phydev)
@@ -834,7 +821,6 @@ static int m88e1121_config_init(struct phy_device *phydev)
 static int m88e1510_config_init(struct phy_device *phydev)
 {
 	int err;
-	int temp;
 
 	/* SGMII-to-Copper mode initialization */
 	if (phydev->interface == PHY_INTERFACE_MODE_SGMII) {
@@ -846,16 +832,15 @@ static int m88e1510_config_init(struct phy_device *phydev)
 			return err;
 
 		/* In reg 20, write MODE[2:0] = 0x1 (SGMII to Copper) */
-		temp = phy_read(phydev, MII_88E1510_GEN_CTRL_REG_1);
-		temp &= ~MII_88E1510_GEN_CTRL_REG_1_MODE_MASK;
-		temp |= MII_88E1510_GEN_CTRL_REG_1_MODE_SGMII;
-		err = phy_write(phydev, MII_88E1510_GEN_CTRL_REG_1, temp);
+		err = phy_modify(phydev, MII_88E1510_GEN_CTRL_REG_1,
+				 ~MII_88E1510_GEN_CTRL_REG_1_MODE_MASK,
+				 MII_88E1510_GEN_CTRL_REG_1_MODE_SGMII);
 		if (err < 0)
 			return err;
 
 		/* PHY reset is necessary after changing MODE[2:0] */
-		temp |= MII_88E1510_GEN_CTRL_REG_1_RESET;
-		err = phy_write(phydev, MII_88E1510_GEN_CTRL_REG_1, temp);
+		err = phy_modify(phydev, MII_88E1510_GEN_CTRL_REG_1, 0,
+				 MII_88E1510_GEN_CTRL_REG_1_RESET);
 		if (err < 0)
 			return err;
 
@@ -961,7 +946,6 @@ static int m88e1149_config_init(struct phy_device *phydev)
 
 static int m88e1145_config_init_rgmii(struct phy_device *phydev)
 {
-	int temp;
 	int err;
 
 	err = m88e1111_config_init_rgmii_delays(phydev);
@@ -973,15 +957,9 @@ static int m88e1145_config_init_rgmii(struct phy_device *phydev)
 		if (err < 0)
 			return err;
 
-		temp = phy_read(phydev, 0x1e);
-		if (temp < 0)
-			return temp;
-
-		temp &= 0xf03f;
-		temp |= 2 << 9;	/* 36 ohm */
-		temp |= 2 << 6;	/* 39 ohm */
-
-		err = phy_write(phydev, 0x1e, temp);
+		err = phy_modify(phydev, 0x1e, 0xf03f,
+				 2 << 9 | /* 36 ohm */
+				 2 << 6); /* 39 ohm */
 		if (err < 0)
 			return err;
 
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index b15b31ca2618..e5ddc5ae56d1 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1328,9 +1328,8 @@ static int genphy_config_eee_advert(struct phy_device *phydev)
  */
 int genphy_setup_forced(struct phy_device *phydev)
 {
-	int ctl = phy_read(phydev, MII_BMCR);
+	u16 ctl = 0;
 
-	ctl &= BMCR_LOOPBACK | BMCR_ISOLATE | BMCR_PDOWN;
 	phydev->pause = 0;
 	phydev->asym_pause = 0;
 
@@ -1342,7 +1341,8 @@ int genphy_setup_forced(struct phy_device *phydev)
 	if (DUPLEX_FULL == phydev->duplex)
 		ctl |= BMCR_FULLDPLX;
 
-	return phy_write(phydev, MII_BMCR, ctl);
+	return phy_modify(phydev, MII_BMCR,
+			  BMCR_LOOPBACK | BMCR_ISOLATE | BMCR_PDOWN, ctl);
 }
 EXPORT_SYMBOL(genphy_setup_forced);
 
@@ -1352,17 +1352,9 @@ EXPORT_SYMBOL(genphy_setup_forced);
  */
 int genphy_restart_aneg(struct phy_device *phydev)
 {
-	int ctl = phy_read(phydev, MII_BMCR);
-
-	if (ctl < 0)
-		return ctl;
-
-	ctl |= BMCR_ANENABLE | BMCR_ANRESTART;
-
 	/* Don't isolate the PHY if we're negotiating */
-	ctl &= ~BMCR_ISOLATE;
-
-	return phy_write(phydev, MII_BMCR, ctl);
+	return phy_modify(phydev, MII_BMCR, ~BMCR_ISOLATE,
+			  BMCR_ANENABLE | BMCR_ANRESTART);
 }
 EXPORT_SYMBOL(genphy_restart_aneg);
 
@@ -1628,44 +1620,20 @@ EXPORT_SYMBOL(genphy_config_init);
 
 int genphy_suspend(struct phy_device *phydev)
 {
-	int value;
-
-	mutex_lock(&phydev->lock);
-
-	value = phy_read(phydev, MII_BMCR);
-	phy_write(phydev, MII_BMCR, value | BMCR_PDOWN);
-
-	mutex_unlock(&phydev->lock);
-
-	return 0;
+	return phy_modify(phydev, MII_BMCR, 0, BMCR_PDOWN);
 }
 EXPORT_SYMBOL(genphy_suspend);
 
 int genphy_resume(struct phy_device *phydev)
 {
-	int value;
-
-	value = phy_read(phydev, MII_BMCR);
-	phy_write(phydev, MII_BMCR, value & ~BMCR_PDOWN);
-
-	return 0;
+	return phy_modify(phydev, MII_BMCR, ~BMCR_PDOWN, 0);
 }
 EXPORT_SYMBOL(genphy_resume);
 
 int genphy_loopback(struct phy_device *phydev, bool enable)
 {
-	int value;
-
-	value = phy_read(phydev, MII_BMCR);
-	if (value < 0)
-		return value;
-
-	if (enable)
-		value |= BMCR_LOOPBACK;
-	else
-		value &= ~BMCR_LOOPBACK;
-
-	return phy_write(phydev, MII_BMCR, value);
+	return phy_modify(phydev, MII_BMCR, ~BMCR_LOOPBACK,
+			  enable ? BMCR_LOOPBACK : 0);
 }
 EXPORT_SYMBOL(genphy_loopback);
 
-- 
2.7.4