[PATCH 2/4] net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable

From: Alexandru Ardelean
Date: Tue Sep 03 2019 - 09:07:06 EST


This driver becomes the first user of the kernel's `ETHTOOL_PHY_EDPD`
phy-tunable feature.
EDPD is also enabled by default on PHY config_init, but can be disabled via
the phy-tunable control.

When enabling EDPD, it's also a good idea (for the ADIN PHYs) to enable TX
periodic pulses, so that in case the other PHY is also on EDPD mode, there
is no lock-up situation where both sides are waiting for the other to
transmit.

Via the phy-tunable control, TX pulses can be disabled if specifying 0
`tx-interval` via ethtool.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---
drivers/net/phy/adin.c | 50 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)

diff --git a/drivers/net/phy/adin.c b/drivers/net/phy/adin.c
index 4dec83df048d..742728ab2a5d 100644
--- a/drivers/net/phy/adin.c
+++ b/drivers/net/phy/adin.c
@@ -26,6 +26,11 @@

#define ADIN1300_RX_ERR_CNT 0x0014

+#define ADIN1300_PHY_CTRL_STATUS2 0x0015
+#define ADIN1300_NRG_PD_EN BIT(3)
+#define ADIN1300_NRG_PD_TX_EN BIT(2)
+#define ADIN1300_NRG_PD_STATUS BIT(1)
+
#define ADIN1300_PHY_CTRL2 0x0016
#define ADIN1300_DOWNSPEED_AN_100_EN BIT(11)
#define ADIN1300_DOWNSPEED_AN_10_EN BIT(10)
@@ -328,12 +333,51 @@ static int adin_set_downshift(struct phy_device *phydev, u8 cnt)
ADIN1300_DOWNSPEEDS_EN);
}

+static int adin_get_edpd(struct phy_device *phydev, u16 *tx_interval)
+{
+ int val;
+
+ val = phy_read(phydev, ADIN1300_PHY_CTRL_STATUS2);
+ if (val < 0)
+ return val;
+
+ if (ADIN1300_NRG_PD_EN & val) {
+ if (val & ADIN1300_NRG_PD_TX_EN)
+ *tx_interval = 1;
+ else
+ *tx_interval = ETHTOOL_PHY_EDPD_NO_TX;
+ } else {
+ *tx_interval = ETHTOOL_PHY_EDPD_DISABLE;
+ }
+
+ return 0;
+}
+
+static int adin_set_edpd(struct phy_device *phydev, u16 tx_interval)
+{
+ u16 val;
+
+ if (tx_interval == ETHTOOL_PHY_EDPD_DISABLE)
+ return phy_clear_bits(phydev, ADIN1300_PHY_CTRL_STATUS2,
+ (ADIN1300_NRG_PD_EN | ADIN1300_NRG_PD_TX_EN));
+
+ val = ADIN1300_NRG_PD_EN;
+ if (tx_interval != ETHTOOL_PHY_EDPD_NO_TX)
+ val |= ADIN1300_NRG_PD_TX_EN;
+
+ return phy_modify(phydev, ADIN1300_PHY_CTRL_STATUS2,
+ (ADIN1300_NRG_PD_EN | ADIN1300_NRG_PD_TX_EN),
+ val);
+}
+
static int adin_get_tunable(struct phy_device *phydev,
struct ethtool_tunable *tuna, void *data)
{
switch (tuna->id) {
case ETHTOOL_PHY_DOWNSHIFT:
return adin_get_downshift(phydev, data);
+ case ETHTOOL_PHY_EDPD:
+ return adin_get_edpd(phydev, data);
default:
return -EOPNOTSUPP;
}
@@ -345,6 +389,8 @@ static int adin_set_tunable(struct phy_device *phydev,
switch (tuna->id) {
case ETHTOOL_PHY_DOWNSHIFT:
return adin_set_downshift(phydev, *(const u8 *)data);
+ case ETHTOOL_PHY_EDPD:
+ return adin_set_edpd(phydev, *(const u16 *)data);
default:
return -EOPNOTSUPP;
}
@@ -368,6 +414,10 @@ static int adin_config_init(struct phy_device *phydev)
if (rc < 0)
return rc;

+ rc = adin_set_edpd(phydev, 1);
+ if (rc < 0)
+ return rc;
+
phydev_dbg(phydev, "PHY is using mode '%s'\n",
phy_modes(phydev->interface));

--
2.20.1