[PATCH v2 4/6] net: phy: DP83640: Add EDPD management

[Bastien Curutchet <bastien.curutchet@bootlin.com>]

The driver does not support enabling/disabling Energy Detect Power Down
(EDPD).
The PHY itself support EDPD.

Add missing part in the driver in order to have this support based on
ethtool {set,get}_phy_tunable functions.

Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
---
 drivers/net/phy/dp83640.c     | 62 +++++++++++++++++++++++++++++++++++
 drivers/net/phy/dp83640_reg.h |  4 +++
 2 files changed, 66 insertions(+)

diff --git a/drivers/net/phy/dp83640.c b/drivers/net/phy/dp83640.c
index c46c81ef0ad0..16c9fda50b19 100644
--- a/drivers/net/phy/dp83640.c
+++ b/drivers/net/phy/dp83640.c
@@ -1531,6 +1531,66 @@ static void dp83640_remove(struct phy_device *phydev)
 	kfree(dp83640);
 }
 
+static int dp83640_get_edpd(struct phy_device *phydev, u16 *edpd)
+{
+	int val;
+
+	phy_write(phydev, PAGESEL, 0);
+	val = phy_read(phydev, EDCR);
+	if (val & ED_EN)
+		*edpd = 2000; /* 2 seconds */
+	else
+		*edpd = ETHTOOL_PHY_EDPD_DISABLE;
+
+	return 0;
+}
+
+static int dp83640_set_edpd(struct phy_device *phydev, u16 edpd)
+{
+	int val;
+
+	phy_write(phydev, PAGESEL, 0);
+	val = phy_read(phydev, EDCR);
+
+	switch (edpd) {
+	case ETHTOOL_PHY_EDPD_DFLT_TX_MSECS:
+	case 2000: /* 2 seconds */
+		val |= ED_EN;
+		break;
+	case ETHTOOL_PHY_EDPD_DISABLE:
+		val &= ~ED_EN;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	phy_write(phydev, EDCR, val);
+
+	return 0;
+}
+
+static int dp83640_get_tunable(struct phy_device *phydev,
+			       struct ethtool_tunable *tuna, void *data)
+{
+	switch (tuna->id) {
+	case ETHTOOL_PHY_EDPD:
+		return dp83640_get_edpd(phydev, data);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int dp83640_set_tunable(struct phy_device *phydev,
+			       struct ethtool_tunable *tuna, const void *data)
+{
+	switch (tuna->id) {
+	case ETHTOOL_PHY_EDPD:
+		return dp83640_set_edpd(phydev, *(u16 *)data);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
 static int dp83640_led_brightness_set(struct phy_device *phydev, u8 index,
 				      enum led_brightness brightness)
 {
@@ -1692,6 +1752,8 @@ static struct phy_driver dp83640_driver = {
 	.name		= "NatSemi DP83640",
 	/* PHY_BASIC_FEATURES */
 	.probe		= dp83640_probe,
+	.get_tunable    = dp83640_get_tunable,
+	.set_tunable    = dp83640_set_tunable,
 	.remove		= dp83640_remove,
 	.soft_reset	= dp83640_soft_reset,
 	.config_init	= dp83640_config_init,
diff --git a/drivers/net/phy/dp83640_reg.h b/drivers/net/phy/dp83640_reg.h
index 09dd2d2527c7..bf34d422d91e 100644
--- a/drivers/net/phy/dp83640_reg.h
+++ b/drivers/net/phy/dp83640_reg.h
@@ -9,6 +9,7 @@
 #define LEDCR                     0x0018 /* PHY Control Register */
 #define PHYCR                     0x0019 /* PHY Control Register */
 #define PHYCR2                    0x001c /* PHY Control Register 2 */
+#define EDCR                      0x001D /* Energy Detect Control Register */
 
 #define PAGE4                     0x0004
 #define PTP_CTL                   0x0014 /* PTP Control Register */
@@ -64,6 +65,9 @@
 /* Bit definitions for the PHYCR2 register */
 #define BC_WRITE                  (1<<11) /* Broadcast Write Enable */
 
+/* Bit definitions for the EDCR register */
+#define ED_EN		          BIT(15) /* Enable Energy Detect Mode */
+
 /* Bit definitions for the PTP_CTL register */
 #define TRIG_SEL_SHIFT            (10)    /* PTP Trigger Select */
 #define TRIG_SEL_MASK             (0x7)
-- 
2.43.0