[PATCH v4 net-next 1/3] lan78xx: Lan7801 Support for Fixed PHY

[Raghuram Chary J <raghuramchary.jallipalli@microchip.com>]

Adding Fixed PHY support to the lan78xx driver.

Signed-off-by: Raghuram Chary J <raghuramchary.jallipalli@microchip.com>
---
v0->v1:
   * Remove driver version #define
   * Modify netdev_info to netdev_dbg
   * Move lan7801 specific to new routine and add switch case
   * Minor cleanup

v1->v2:
   * Removed fixedphy variable and used phy_is_pseudo_fixed_link() check.
v2->v3:
   * Revert driver version, debug statment changes for separate patch.
   * Modify lan7801 specific routine with return type struct phy_device.
v3->v4:
   * Modify lan7801 specific routine by removing phydev arg and get phydev.
---
 drivers/net/usb/Kconfig   |   1 +
 drivers/net/usb/lan78xx.c | 100 +++++++++++++++++++++++++++++++++-------------
 2 files changed, 73 insertions(+), 28 deletions(-)

diff --git a/drivers/net/usb/Kconfig b/drivers/net/usb/Kconfig
index f28bd74ac275..418b0904cecb 100644
--- a/drivers/net/usb/Kconfig
+++ b/drivers/net/usb/Kconfig
@@ -111,6 +111,7 @@ config USB_LAN78XX
 	select MII
 	select PHYLIB
 	select MICROCHIP_PHY
+	select FIXED_PHY
 	help
 	  This option adds support for Microchip LAN78XX based USB 2
 	  & USB 3 10/100/1000 Ethernet adapters.
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 0867f7275852..cb35cfa20ca0 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -36,7 +36,7 @@
 #include <linux/irq.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/microchipphy.h>
-#include <linux/phy.h>
+#include <linux/phy_fixed.h>
 #include "lan78xx.h"
 
 #define DRIVER_AUTHOR	"WOOJUNG HUH <woojung.huh@microchip.com>"
@@ -2003,52 +2003,91 @@ static int ksz9031rnx_fixup(struct phy_device *phydev)
 	return 1;
 }
 
-static int lan78xx_phy_init(struct lan78xx_net *dev)
+static struct phy_device *lan7801_phy_init(struct lan78xx_net *dev)
 {
+	u32 buf;
 	int ret;
-	u32 mii_adv;
+	struct fixed_phy_status fphy_status = {
+		.link = 1,
+		.speed = SPEED_1000,
+		.duplex = DUPLEX_FULL,
+	};
 	struct phy_device *phydev;
 
 	phydev = phy_find_first(dev->mdiobus);
 	if (!phydev) {
-		netdev_err(dev->net, "no PHY found\n");
-		return -EIO;
-	}
-
-	if ((dev->chipid == ID_REV_CHIP_ID_7800_) ||
-	    (dev->chipid == ID_REV_CHIP_ID_7850_)) {
-		phydev->is_internal = true;
-		dev->interface = PHY_INTERFACE_MODE_GMII;
-
-	} else if (dev->chipid == ID_REV_CHIP_ID_7801_) {
+		netdev_dbg(dev->net, "PHY Not Found!! Registering Fixed PHY\n");
+		phydev = fixed_phy_register(PHY_POLL, &fphy_status, -1,
+					    NULL);
+		if (IS_ERR(phydev)) {
+			netdev_err(dev->net, "No PHY/fixed_PHY found\n");
+			return NULL;
+		}
+		netdev_dbg(dev->net, "Registered FIXED PHY\n");
+		dev->interface = PHY_INTERFACE_MODE_RGMII;
+		ret = lan78xx_write_reg(dev, MAC_RGMII_ID,
+					MAC_RGMII_ID_TXC_DELAY_EN_);
+		ret = lan78xx_write_reg(dev, RGMII_TX_BYP_DLL, 0x3D00);
+		ret = lan78xx_read_reg(dev, HW_CFG, &buf);
+		buf |= HW_CFG_CLK125_EN_;
+		buf |= HW_CFG_REFCLK25_EN_;
+		ret = lan78xx_write_reg(dev, HW_CFG, buf);
+	} else {
 		if (!phydev->drv) {
 			netdev_err(dev->net, "no PHY driver found\n");
-			return -EIO;
+			return NULL;
 		}
-
 		dev->interface = PHY_INTERFACE_MODE_RGMII;
-
 		/* external PHY fixup for KSZ9031RNX */
 		ret = phy_register_fixup_for_uid(PHY_KSZ9031RNX, 0xfffffff0,
 						 ksz9031rnx_fixup);
 		if (ret < 0) {
 			netdev_err(dev->net, "fail to register fixup\n");
-			return ret;
+			return NULL;
 		}
 		/* external PHY fixup for LAN8835 */
 		ret = phy_register_fixup_for_uid(PHY_LAN8835, 0xfffffff0,
 						 lan8835_fixup);
 		if (ret < 0) {
 			netdev_err(dev->net, "fail to register fixup\n");
-			return ret;
+			return NULL;
 		}
 		/* add more external PHY fixup here if needed */
 
 		phydev->is_internal = false;
-	} else {
-		netdev_err(dev->net, "unknown ID found\n");
-		ret = -EIO;
-		goto error;
+	}
+	return phydev;
+}
+
+static int lan78xx_phy_init(struct lan78xx_net *dev)
+{
+	int ret;
+	u32 mii_adv;
+	struct phy_device *phydev;
+
+	switch (dev->chipid) {
+	case ID_REV_CHIP_ID_7801_:
+		phydev = lan7801_phy_init(dev);
+		if (!phydev) {
+			netdev_err(dev->net, "lan7801: PHY Init Failed");
+			return -EIO;
+		}
+		break;
+
+	case ID_REV_CHIP_ID_7800_:
+	case ID_REV_CHIP_ID_7850_:
+		phydev = phy_find_first(dev->mdiobus);
+		if (!phydev) {
+			netdev_err(dev->net, "no PHY found\n");
+			return -EIO;
+		}
+		phydev->is_internal = true;
+		dev->interface = PHY_INTERFACE_MODE_GMII;
+		break;
+
+	default:
+		netdev_err(dev->net, "Unknown CHIP ID found\n");
+		return -EIO;
 	}
 
 	/* if phyirq is not set, use polling mode in phylib */
@@ -2067,6 +2106,12 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
 	if (ret) {
 		netdev_err(dev->net, "can't attach PHY to %s\n",
 			   dev->mdiobus->id);
+		if (dev->chipid == ID_REV_CHIP_ID_7801_) {
+			phy_unregister_fixup_for_uid(PHY_KSZ9031RNX,
+						     0xfffffff0);
+			phy_unregister_fixup_for_uid(PHY_LAN8835,
+						     0xfffffff0);
+		}
 		return -EIO;
 	}
 
@@ -2084,12 +2129,6 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
 	dev->fc_autoneg = phydev->autoneg;
 
 	return 0;
-
-error:
-	phy_unregister_fixup_for_uid(PHY_KSZ9031RNX, 0xfffffff0);
-	phy_unregister_fixup_for_uid(PHY_LAN8835, 0xfffffff0);
-
-	return ret;
 }
 
 static int lan78xx_set_rx_max_frame_length(struct lan78xx_net *dev, int size)
@@ -3487,6 +3526,7 @@ static void lan78xx_disconnect(struct usb_interface *intf)
 	struct lan78xx_net		*dev;
 	struct usb_device		*udev;
 	struct net_device		*net;
+	struct phy_device		*phydev;
 
 	dev = usb_get_intfdata(intf);
 	usb_set_intfdata(intf, NULL);
@@ -3495,12 +3535,16 @@ static void lan78xx_disconnect(struct usb_interface *intf)
 
 	udev = interface_to_usbdev(intf);
 	net = dev->net;
+	phydev = net->phydev;
 
 	phy_unregister_fixup_for_uid(PHY_KSZ9031RNX, 0xfffffff0);
 	phy_unregister_fixup_for_uid(PHY_LAN8835, 0xfffffff0);
 
 	phy_disconnect(net->phydev);
 
+	if (phy_is_pseudo_fixed_link(phydev))
+		fixed_phy_unregister(phydev);
+
 	unregister_netdev(net);
 
 	cancel_delayed_work_sync(&dev->wq);
-- 
2.16.2