realtek: mdio: refactor RTL930x port ability setup

Provide a separate function to setup the ability (SDS/MDIO) of a RTL930x
port. This simplifies rtmdio_930x_setup_polling().  With this commit the
driver does no longer unconditionally overwrite reserved register bits.

Add a return value for the new function to indicate failure/success. As
of now this will be silently ignored in the caller. A future commit will
take care about that.

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://github.com/openwrt/openwrt/pull/23204
Signed-off-by: Robert Marko <robimarko@gmail.com>

diff --git a/target/linux/realtek/files-6.18/drivers/net/mdio/mdio-realtek-otto.c b/target/linux/realtek/files-6.18/drivers/net/mdio/mdio-realtek-otto.c
index 6d617e510c2e5271a9cdf99cf53d30e4c8e8bb55..ddb61cef4f3462868571c4e333dd27e1845bf6db 100644 (file)
--- a/target/linux/realtek/files-6.18/drivers/net/mdio/mdio-realtek-otto.c
+++ b/target/linux/realtek/files-6.18/drivers/net/mdio/mdio-realtek-otto.c
@@ -37,6 +37,7 @@
 
 #define RTMDIO_PHY_MAC_1G                      3
 #define RTMDIO_PHY_MAC_2G_PLUS                 1
+#define RTMDIO_PHY_MAC_SDS                     0
 
 #define RTMDIO_PHY_POLL_MMD(dev, reg, bit)     ((((bit) & GENMASK(3, 0)) << 21) | \
                                                 (((dev) & GENMASK(4, 0)) << 16) | \
@@ -747,23 +748,38 @@ static int rtmdio_930x_setup_ctrl(struct rtmdio_ctrl *ctrl)
        return 0;
 }
 
+static int rtmdio_930x_set_port_ability(struct rtmdio_ctrl *ctrl, u32 pn, u32 ability)
+{
+       u32 mask, val;
+
+       if (pn >= ctrl->cfg->num_phys)
+               return -EINVAL;
+       /*
+        * Hardware accepts only register values 0-3 but uses 2 types of fields. Ports 0-23 are
+        * grouped by 4 with 2 field bits. Ports 24-27 are handled individually with 3 field bits.
+        */
+       mask = pn < 24 ? GENMASK(1, 0) << ((pn / 4) * 2) : GENMASK(2, 0) << ((pn - 24) * 3 + 12);
+       val = ability << __ffs(mask);
+
+       return regmap_update_bits(ctrl->map, RTMDIO_930X_SMI_MAC_TYPE_CTRL, mask, val);
+}
+
 static void rtmdio_930x_setup_polling(struct rtmdio_ctrl *ctrl)
 {
        struct rtmdio_phy_info phyinfo;
-       unsigned int mask, val, pn;
+       unsigned int pn;
 
-       /* set everthing to "SerDes driven" */
-       regmap_write(ctrl->map, RTMDIO_930X_SMI_MAC_TYPE_CTRL, 0);
+       /* set all ports to "SerDes driven" */
+       for (pn = 0; pn < ctrl->cfg->num_phys; pn++)
+               rtmdio_930x_set_port_ability(ctrl, pn, RTMDIO_PHY_MAC_SDS);
 
        /* Define PHY specific polling parameters */
        for_each_port(ctrl, pn) {
                if (rtmdio_get_phy_info(ctrl, pn, &phyinfo))
                        continue;
 
-               /* set to "PHY driven" */
-               mask = pn > 23 ? 0x7 << ((pn - 24) * 3 + 12) : 0x3 << ((pn / 4) * 2);
-               val = phyinfo.mac_type << (ffs(mask) - 1);
-               regmap_update_bits(ctrl->map, RTMDIO_930X_SMI_MAC_TYPE_CTRL, mask, val);
+               /* set port to "PHY driven" */
+               rtmdio_930x_set_port_ability(ctrl, pn, phyinfo.mac_type);
 
                /* polling via standard or resolution register */
                regmap_assign_bits(ctrl->map, RTMDIO_930X_SMI_GLB_CTRL,