WARNING: please write a help paragraph that fully describes the config symbol
#28: FILE: drivers/net/mdio/Kconfig:188:
+config MDIO_REALTEK_RTL
+	tristate "Realtek RTL9300 MDIO interface support"
+	depends on MACH_REALTEK_RTL || COMPILE_TEST
+	help
+	  This driver supports the MDIO interface found in the Realtek
+	  RTL9300 family of Ethernet switches with integrated SoC.
+

WARNING: added, moved or deleted file(s), does MAINTAINERS need updating?
#51: 
new file mode 100644

WARNING: line length of 93 exceeds 80 columns
#102: FILE: drivers/net/mdio/mdio-realtek-rtl.c:47:
+	return regmap_read_poll_timeout(priv->regmap, priv->reg_base + SMI_ACCESS_PHY_CTRL_1,

WARNING: line length of 91 exceeds 80 columns
#106: FILE: drivers/net/mdio/mdio-realtek-rtl.c:51:
+static int realtek_mdio_read_c45(struct mii_bus *bus, int phy_id, int dev_addr, int regnum)

WARNING: line length of 95 exceeds 80 columns
#116: FILE: drivers/net/mdio/mdio-realtek-rtl.c:61:
+	err = regmap_write(priv->regmap, priv->reg_base + SMI_ACCESS_PHY_CTRL_2, phy_id << 16);

WARNING: line length of 86 exceeds 80 columns
#143: FILE: drivers/net/mdio/mdio-realtek-rtl.c:88:
+	err = regmap_read(priv->regmap, priv->reg_base + SMI_ACCESS_PHY_CTRL_2, &val);

WARNING: line length of 94 exceeds 80 columns
#161: FILE: drivers/net/mdio/mdio-realtek-rtl.c:106:
+	err = regmap_write(priv->regmap, priv->reg_base + SMI_ACCESS_PHY_CTRL_0, BIT(phy_id));

WARNING: line length of 94 exceeds 80 columns
#165: FILE: drivers/net/mdio/mdio-realtek-rtl.c:110:
+	err = regmap_write(priv->regmap, priv->reg_base + SMI_ACCESS_PHY_CTRL_2, value << 16);

WARNING: line length of 92 exceeds 80 columns
#179: FILE: drivers/net/mdio/mdio-realtek-rtl.c:124:
+	err = regmap_read_poll_timeout(priv->regmap, priv->reg_base + SMI_ACCESS_PHY_CTRL_1,

WARNING: line length of 85 exceeds 80 columns
#219: FILE: drivers/net/mdio/mdio-realtek-rtl.c:164:
+	err = regmap_bulk_write(priv->regmap, priv->reg_base + SMI_PORT0_5_ADDR_CTRL,

WARNING: line length of 88 exceeds 80 columns
#224: FILE: drivers/net/mdio/mdio-realtek-rtl.c:169:
+	err = regmap_bulk_write(priv->regmap, priv->reg_base + SMI_PORT0_15_POLLING_SEL,

WARNING: line length of 91 exceeds 80 columns
#273: FILE: drivers/net/mdio/mdio-realtek-rtl.c:218:
+			return dev_err_probe(dev, -EINVAL, "illegal port number %d\n", pn);

WARNING: line length of 96 exceeds 80 columns
#275: FILE: drivers/net/mdio/mdio-realtek-rtl.c:220:
+		err = fwnode_property_read_u32_array(child, "realtek,smi-address", smi_addr, 2);

WARNING: line length of 85 exceeds 80 columns
#281: FILE: drivers/net/mdio/mdio-realtek-rtl.c:226:
+		if (fwnode_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))

WARNING: line length of 93 exceeds 80 columns
#290: FILE: drivers/net/mdio/mdio-realtek-rtl.c:235:
+		return dev_err_probe(dev, err, "failed to initialise MDIO bus controller\n");

total: 0 errors, 15 warnings, 0 checks, 284 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 05dbe9987140 ("net: mdio: Add RTL9300 MDIO driver") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
total: 0 errors, 15 warnings, 0 checks, 284 lines checked