[PATCH net-next 1/2] net: phy: at803x: use paged reads

[PATCH net-next 1/2] net: phy: at803x: use paged reads

[David Bauer]

Refactor the page-switching in at803x_aneg_done to use
paged reads as suggested by Andrew Lunn.

This way, potential race conditions are avoided, as the
MDIO lock was previously not taken.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David Bauer <mail@david-bauer.net>
---
 drivers/net/phy/at803x.c | 42 +++++++++++++++++++++++++++++++++++-----
 1 file changed, 37 insertions(+), 5 deletions(-)

diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index c2aa4c92edde..b3243ad570c7 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -144,6 +144,9 @@
 #define ATH8035_PHY_ID 0x004dd072
 #define AT8030_PHY_ID_MASK			0xffffffef
 
+#define AT803X_PAGE_FIBER		0
+#define AT803X_PAGE_COPPER		1
+
 MODULE_DESCRIPTION("Qualcomm Atheros AR803x PHY driver");
 MODULE_AUTHOR("Matus Ujhelyi");
 MODULE_LICENSE("GPL");
@@ -198,6 +201,35 @@ static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg,
 	return phy_write(phydev, AT803X_DEBUG_DATA, val);
 }
 
+static int at803x_write_page(struct phy_device *phydev, int page)
+{
+	int mask;
+	int set;
+
+	if (page == AT803X_PAGE_COPPER) {
+		set = AT803X_BT_BX_REG_SEL;
+		mask = 0;
+	} else {
+		set = 0;
+		mask = AT803X_BT_BX_REG_SEL;
+	}
+
+	return __phy_modify(phydev, AT803X_REG_CHIP_CONFIG, mask, set);
+}
+
+static int at803x_read_page(struct phy_device *phydev)
+{
+	int ccr = __phy_read(phydev, AT803X_REG_CHIP_CONFIG);
+
+	if (ccr < 0)
+		return ccr;
+
+	if (ccr & AT803X_BT_BX_REG_SEL)
+		return AT803X_PAGE_COPPER;
+
+	return AT803X_PAGE_FIBER;
+}
+
 static int at803x_enable_rx_delay(struct phy_device *phydev)
 {
 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0, 0,
@@ -753,6 +785,7 @@ static void at803x_link_change_notify(struct phy_device *phydev)
 
 static int at803x_aneg_done(struct phy_device *phydev)
 {
+	int pssr;
 	int ccr;
 
 	int aneg_done = genphy_aneg_done(phydev);
@@ -767,16 +800,13 @@ static int at803x_aneg_done(struct phy_device *phydev)
 	if ((ccr & AT803X_MODE_CFG_MASK) != AT803X_MODE_CFG_SGMII)
 		return aneg_done;
 
-	/* switch to SGMII/fiber page */
-	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr & ~AT803X_BT_BX_REG_SEL);
+	pssr = phy_read_paged(phydev, AT803X_PAGE_FIBER, AT803X_PSSR);
 
 	/* check if the SGMII link is OK. */
-	if (!(phy_read(phydev, AT803X_PSSR) & AT803X_PSSR_MR_AN_COMPLETE)) {
+	if (!(pssr & AT803X_PSSR_MR_AN_COMPLETE)) {
 		phydev_warn(phydev, "803x_aneg_done: SGMII link is not ok\n");
 		aneg_done = 0;
 	}
-	/* switch back to copper page */
-	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr | AT803X_BT_BX_REG_SEL);
 
 	return aneg_done;
 }
@@ -1196,6 +1226,8 @@ static struct phy_driver at803x_driver[] = {
 	.get_wol		= at803x_get_wol,
 	.suspend		= at803x_suspend,
 	.resume			= at803x_resume,
+	.read_page		= at803x_read_page,
+	.write_page		= at803x_write_page,
 	/* PHY_GBIT_FEATURES */
 	.read_status		= at803x_read_status,
 	.aneg_done		= at803x_aneg_done,
-- 
2.31.1

[PATCH net-next 2/2] net: phy: at803x: select correct page on config init

[David Bauer]

The Atheros AR8031 and AR8033 expose different registers for SGMII/Fiber
as well as the copper side of the PHY depending on the BT_BX_REG_SEL bit
in the chip configure register.

The driver assumes the copper side is selected on probe, but this might
not be the case depending which page was last selected by the
bootloader. Notably, Ubiquiti UniFi bootloaders show this behavior.

Select the copper page when probing to circumvent this.

Signed-off-by: David Bauer <mail@david-bauer.net>
---
 drivers/net/phy/at803x.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index b3243ad570c7..b63d2c1575bb 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -567,6 +567,7 @@ static int at803x_probe(struct phy_device *phydev)
 {
 	struct device *dev = &phydev->mdio.dev;
 	struct at803x_priv *priv;
+	int ret;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -574,7 +575,20 @@ static int at803x_probe(struct phy_device *phydev)
 
 	phydev->priv = priv;
 
-	return at803x_parse_dt(phydev);
+	ret = at803x_parse_dt(phydev);
+	if (ret)
+		return ret;
+
+	/* Some bootloaders leave the fiber page selected.
+	 * Switch to the copper page, as otherwise we read
+	 * the PHY capabilities from the fiber side.
+	 */
+	if (at803x_match_phy_id(phydev, ATH8031_PHY_ID)) {
+		ret = phy_select_page(phydev, AT803X_PAGE_COPPER);
+		ret = phy_restore_page(phydev, AT803X_PAGE_COPPER, ret);
+	}
+
+	return ret;
 }
 
 static void at803x_remove(struct phy_device *phydev)
-- 
2.31.1