[openwrt/openwrt] realtek: simplify RTL8218B/RTL8214Fx detection

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/926ffa10b40855889149c4a78d01cdeda2b821db

commit 926ffa10b40855889149c4a78d01cdeda2b821db
Author: Markus Stockhausen <markus.stockhausen at gmx.de>
AuthorDate: Fri Jul 11 06:58:59 2025 -0400

    realtek: simplify RTL8218B/RTL8214Fx detection
    
    The current implementation has several issues:
    
    - it uses the hacky phy_port* macros
    - it uses SoC dependent raw pages
    - it disables/enables SoC dependent polling
    
    Get rid of these dependencies and access the mdio bus the normal way.
    
    Signed-off-by: Markus Stockhausen <markus.stockhausen at gmx.de>
    Link: https://github.com/openwrt/openwrt/pull/19372
    Signed-off-by: Hauke Mehrtens <hauke at hauke-m.de>
---
 .../files-6.12/drivers/net/phy/rtl83xx-phy.c       | 49 +++++++++-------------
 1 file changed, 19 insertions(+), 30 deletions(-)

diff --git a/target/linux/realtek/files-6.12/drivers/net/phy/rtl83xx-phy.c b/target/linux/realtek/files-6.12/drivers/net/phy/rtl83xx-phy.c
index f8eddaec4f..e794b1296d 100644
--- a/target/linux/realtek/files-6.12/drivers/net/phy/rtl83xx-phy.c
+++ b/target/linux/realtek/files-6.12/drivers/net/phy/rtl83xx-phy.c
@@ -22,10 +22,8 @@ extern struct rtl83xx_soc_info soc_info;
 extern struct mutex smi_lock;
 extern int phy_package_port_write_paged(struct phy_device *phydev, int port, int page, u32 regnum, u16 val);
 extern int phy_package_write_paged(struct phy_device *phydev, int page, u32 regnum, u16 val);
-extern int phy_port_write_paged(struct phy_device *phydev, int port, int page, u32 regnum, u16 val);
 extern int phy_package_port_read_paged(struct phy_device *phydev, int port, int page, u32 regnum);
 extern int phy_package_read_paged(struct phy_device *phydev, int page, u32 regnum);
-extern int phy_port_read_paged(struct phy_device *phydev, int port, int page, u32 regnum);
 
 #define PHY_PAGE_2	2
 #define PHY_PAGE_4	4
@@ -157,9 +155,9 @@ static int resume_polling(u64 saved_state)
 
 static int rtl821x_match_phy_device(struct phy_device *phydev)
 {
-	u64 poll_state;
-	int rawpage, port = phydev->mdio.addr & ~3;
-	int oldpage, chip_mode, chip_cfg_mode;
+	int oldpage, oldxpage, chip_mode, chip_cfg_mode;
+	struct mii_bus *bus = phydev->mdio.bus;
+	int addr = phydev->mdio.addr & ~3;
 
 	if (phydev->phy_id == PHY_ID_RTL8218B_E)
 		return PHY_IS_RTL8218B_E;
@@ -167,36 +165,27 @@ static int rtl821x_match_phy_device(struct phy_device *phydev)
 	if (phydev->phy_id != PHY_ID_RTL8214_OR_8218)
 		return PHY_IS_NOT_RTL821X;
 
-	if (soc_info.family == RTL8380_FAMILY_ID)
-		rawpage = RTL838X_PAGE_RAW;
-	else if (soc_info.family == RTL8390_FAMILY_ID)
-		rawpage = RTL839X_PAGE_RAW;
-	else
-		return PHY_IS_NOT_RTL821X;
-
-	poll_state = disable_polling(port);
 	/*
-	 * At this stage the write_page()/read_page() PHY functions are not yet
-	 * registered and normal paged access is not possible. The following
-	 * detection routine works because our MDIO bus has all the Realtek
-	 * PHY page handling (register 31) integrated into the port functions.
+	 * RTL8214FC and RTL8218B are the same PHYs with different configurations. That info is
+	 * stored in the first PHY of the package. In all known configurations packages start at
+	 * bus addresses that are multiples of four. Avoid paged access as this is not available
+	 * during detection.
 	 */
-	oldpage = phy_port_read_paged(phydev, port, rawpage, 31);
-	phy_port_write_paged(phydev, port, rawpage, 31, 0xa42);
-	phy_port_write_paged(phydev, port, rawpage, 29, 0x008);
-	phy_port_write_paged(phydev, port, rawpage, 31, 0x278);
-	phy_port_write_paged(phydev, port, rawpage, 18, 0x455);
-	phy_port_write_paged(phydev, port, rawpage, 31, 0x260);
-	chip_mode = phy_port_read_paged(phydev, port, rawpage, 18);
-	phy_port_write_paged(phydev, port, rawpage, 31, 0xa42);
-	phy_port_write_paged(phydev, port, rawpage, 29, 0x000);
-	phy_port_write_paged(phydev, port, rawpage, 31, oldpage);
 
-	resume_polling(poll_state);
+	oldpage = mdiobus_read(bus, addr, 0x1f);
+	oldxpage = mdiobus_read(bus, addr, 0x1e);
+
+	mdiobus_write(bus, addr, 0x1e, 0x8);
+	mdiobus_write(bus, addr, 0x1f, 0x278);
+	mdiobus_write(bus, addr, 0x12, 0x455);
+	mdiobus_write(bus, addr, 0x1f, 0x260);
+	chip_mode = mdiobus_read(bus, addr, 0x12);
+	dev_dbg(&phydev->mdio.dev, "got RTL8218B/RTL8214Fx chip mode %04x\n", chip_mode);
 
-	pr_debug("%s(%d): got chip mode %x\n", __func__, phydev->mdio.addr, chip_mode);
+	mdiobus_write(bus, addr, 0x1e, oldxpage);
+	mdiobus_write(bus, addr, 0x1f, oldpage);
 
-	/* we checked the 4th port of a RTL8218B and got no config values */
+	/* no values while reading the 5th port during 5-8th port detection of RTL8218B */
 	if (!chip_mode)
 		return PHY_IS_RTL8218B_E;