[PATCH 4.14 298/496] lan78xx: Set ASD in MAC_CR when EEE is enabled.

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Raghuram Chary J <raghuramchary.jallipalli@xxxxxxxxxxxxx>

[ Upstream commit e69647a19c870c2f919e4d5023af8a515e8ef25f ]

Description:
EEE does not work with lan7800 when AutoSpeed is not set.
(This can happen when EEPROM is not populated or configured incorrectly)

Root-Cause:
When EEE is enabled, the mac config register ASD is not set
i.e. in default state, causing EEE fail.

Fix:
Set the register when eeprom is not present.

Fixes: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
Signed-off-by: Raghuram Chary J <raghuramchary.jallipalli@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/usb/lan78xx.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2352,6 +2352,7 @@ static int lan78xx_reset(struct lan78xx_
 	u32 buf;
 	int ret = 0;
 	unsigned long timeout;
+	u8 sig;
 
 	ret = lan78xx_read_reg(dev, HW_CFG, &buf);
 	buf |= HW_CFG_LRST_;
@@ -2451,6 +2452,15 @@ static int lan78xx_reset(struct lan78xx_
 	/* LAN7801 only has RGMII mode */
 	if (dev->chipid == ID_REV_CHIP_ID_7801_)
 		buf &= ~MAC_CR_GMII_EN_;
+
+	if (dev->chipid == ID_REV_CHIP_ID_7800_) {
+		ret = lan78xx_read_raw_eeprom(dev, 0, 1, &sig);
+		if (!ret && sig != EEPROM_INDICATOR) {
+			/* Implies there is no external eeprom. Set mac speed */
+			netdev_info(dev->net, "No External EEPROM. Setting MAC Speed\n");
+			buf |= MAC_CR_AUTO_DUPLEX_ | MAC_CR_AUTO_SPEED_;
+		}
+	}
 	ret = lan78xx_write_reg(dev, MAC_CR, buf);
 
 	ret = lan78xx_read_reg(dev, MAC_TX, &buf);