[PATCH net-next 4/4] net: phy: realtek: add delay to fix RXC generation issue

[Joakim Zhang <qiangqing.zhang@nxp.com>]

PHY will delay about 11.5ms to generate RXC clock when switching from
power down to normal operation. Read/write registers would also cause RXC
become unstable and stop for a while during this process. Realtek engineer
suggests 15ms or more delay can workaround this issue. All these
statistics are collected with ALDPS mode disabled, so use RTL821X_ALDPS_DISABLE
quirk check.

Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
---
 drivers/net/phy/realtek.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
index 90e3a8cbfc2f..b45deda839f8 100644
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -408,6 +408,22 @@ static int rtl8211f_config_init(struct phy_device *phydev)
 	return genphy_soft_reset(phydev);
 }
 
+static int rtl821x_resume(struct phy_device *phydev)
+{
+	struct rtl821x_priv *priv = phydev->priv;
+	int ret;
+
+	ret = genphy_resume(phydev);
+	if (ret < 0)
+		return ret;
+
+	/* delay time is collected with ALDPS mode disabled. */
+	if (priv->quirks & RTL821X_ALDPS_DISABLE_FEATURE)
+		msleep(20);
+
+	return 0;
+}
+
 static int rtl8211e_config_init(struct phy_device *phydev)
 {
 	int ret = 0, oldpage;
@@ -904,7 +920,7 @@ static struct phy_driver realtek_drvs[] = {
 		.config_intr	= &rtl8211f_config_intr,
 		.handle_interrupt = rtl8211f_handle_interrupt,
 		.suspend	= genphy_suspend,
-		.resume		= genphy_resume,
+		.resume		= rtl821x_resume,
 		.read_page	= rtl821x_read_page,
 		.write_page	= rtl821x_write_page,
 	}, {
-- 
2.17.1