From da702f34e3cc4b6b87ed2d63c17d65d841fa81c6 Mon Sep 17 00:00:00 2001
From: "Radu Pirea (NXP OSS)" <radu-nicolae.pirea@oss.nxp.com>
Date: Mon, 19 Apr 2021 19:13:59 +0300
Subject: [PATCH] net: phy: add genphy_c45_pma_suspend/resume

Add generic PMA suspend and resume callback functions for C45 PHYs.

Signed-off-by: Radu Pirea (NXP OSS) <radu-nicolae.pirea@oss.nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/phy/phy-c45.c | 43 +++++++++++++++++++++++++++++++++++++++
 include/linux/phy.h       |  2 ++
 2 files changed, 45 insertions(+)

diff --git a/drivers/net/phy/phy-c45.c b/drivers/net/phy/phy-c45.c
index 91e3acb9e397..f4816b7d31b3 100644
--- a/drivers/net/phy/phy-c45.c
+++ b/drivers/net/phy/phy-c45.c
@@ -8,6 +8,49 @@
 #include <linux/mii.h>
 #include <linux/phy.h>
 
+/**
+ * genphy_c45_pma_can_sleep - checks if the PMA have sleep support
+ * @phydev: target phy_device struct
+ */
+static bool genphy_c45_pma_can_sleep(struct phy_device *phydev)
+{
+	int stat1;
+
+	stat1 = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_STAT1);
+	if (stat1 < 0)
+		return false;
+
+	return !!(stat1 & MDIO_STAT1_LPOWERABLE);
+}
+
+/**
+ * genphy_c45_pma_resume - wakes up the PMA module
+ * @phydev: target phy_device struct
+ */
+int genphy_c45_pma_resume(struct phy_device *phydev)
+{
+	if (!genphy_c45_pma_can_sleep(phydev))
+		return -EOPNOTSUPP;
+
+	return phy_clear_bits_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1,
+				  MDIO_CTRL1_LPOWER);
+}
+EXPORT_SYMBOL_GPL(genphy_c45_pma_resume);
+
+/**
+ * genphy_c45_pma_suspend - suspends the PMA module
+ * @phydev: target phy_device struct
+ */
+int genphy_c45_pma_suspend(struct phy_device *phydev)
+{
+	if (!genphy_c45_pma_can_sleep(phydev))
+		return -EOPNOTSUPP;
+
+	return phy_set_bits_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1,
+				MDIO_CTRL1_LPOWER);
+}
+EXPORT_SYMBOL_GPL(genphy_c45_pma_suspend);
+
 /**
  * genphy_c45_pma_setup_forced - configures a forced speed
  * @phydev: target phy_device struct
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 98fb441dd72e..e3d4d583463b 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1535,6 +1535,8 @@ int genphy_c45_pma_read_abilities(struct phy_device *phydev);
 int genphy_c45_read_status(struct phy_device *phydev);
 int genphy_c45_config_aneg(struct phy_device *phydev);
 int genphy_c45_loopback(struct phy_device *phydev, bool enable);
+int genphy_c45_pma_resume(struct phy_device *phydev);
+int genphy_c45_pma_suspend(struct phy_device *phydev);
 
 /* Generic C45 PHY driver */
 extern struct phy_driver genphy_c45_driver;