generic: add support for vsc8504 phy

adds support for vsc8504 phy.
patch have use on 5.4 kernel and has
to be dropped after since phy is supported by
CONFIG_MICROSEMI_PHY on newer LTS kernels.

Tested-by: Johannes Kimmel <fff@bareminimum.eu>
Signed-off-by: Roman Kuzmitskii <damex.pp@icloud.com>

target/linux/generic/hack-5.4/703-add_vsc8504_support.patch

@@ -0,0 +1,57 @@
+From: Roman Kuzmitskii <damex.pp@icloud.com>
+Date: Thu, 05 Nov 2020 02:00:00 +0000
+Subject: [PATCH] net: phy: vitesse: add vsc8504 support
+
+This patch adds support for vsc8504 phy.
+That phy is changed owner:
+ vitesse -> microsemi -> microchip
+So is its driver in kernel was changed and rewritten.
+
+there is no need to upstream this patch.
+this vsc8504 is supported by newer kernels out of box.
+support could be enabled by CONFIG_MICROSEMI_PHY.
+
+Tested-by: Johannes Kimmel <fff@bareminimum.eu>
+Signed-off-by: Roman Kuzmitskii <damex.pp@icloud.com>
+--- a/drivers/net/phy/vitesse.c
++++ b/drivers/net/phy/vitesse.c
+@@ -61,6 +61,7 @@
+ 
+ #define PHY_ID_VSC8234			0x000fc620
+ #define PHY_ID_VSC8244			0x000fc6c0
++#define PHY_ID_VSC8504			0x000704c2
+ #define PHY_ID_VSC8572			0x000704d0
+ #define PHY_ID_VSC8601			0x00070420
+ #define PHY_ID_VSC7385			0x00070450
+@@ -292,6 +293,7 @@
+ 		err = phy_write(phydev, MII_VSC8244_IMASK,
+ 			(phydev->drv->phy_id == PHY_ID_VSC8234 ||
+ 			 phydev->drv->phy_id == PHY_ID_VSC8244 ||
++			 phydev->drv->phy_id == PHY_ID_VSC8504 ||
+ 			 phydev->drv->phy_id == PHY_ID_VSC8572 ||
+ 			 phydev->drv->phy_id == PHY_ID_VSC8601) ?
+ 				MII_VSC8244_IMASK_MASK :
+@@ -402,6 +404,15 @@
+ 	.ack_interrupt	= &vsc824x_ack_interrupt,
+ 	.config_intr	= &vsc82xx_config_intr,
+ }, {
++	.phy_id         = PHY_ID_VSC8504,
++	.name           = "Vitesse VSC8504",
++	.phy_id_mask    = 0x000ffff0,
++	/* PHY_GBIT_FEATURES */
++	.config_init    = &vsc824x_config_init,
++	.config_aneg    = &vsc82x4_config_aneg,
++	.ack_interrupt  = &vsc824x_ack_interrupt,
++	.config_intr    = &vsc82xx_config_intr,
++}, {
+ 	.phy_id         = PHY_ID_VSC8572,
+ 	.name           = "Vitesse VSC8572",
+ 	.phy_id_mask    = 0x000ffff0,
+@@ -488,6 +499,7 @@
+ static struct mdio_device_id __maybe_unused vitesse_tbl[] = {
+ 	{ PHY_ID_VSC8234, 0x000ffff0 },
+ 	{ PHY_ID_VSC8244, 0x000fffc0 },
++	{ PHY_ID_VSC8504, 0x000ffff0 },
+ 	{ PHY_ID_VSC8572, 0x000ffff0 },
+ 	{ PHY_ID_VSC7385, 0x000ffff0 },
+ 	{ PHY_ID_VSC7388, 0x000ffff0 },