diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index f4fec5f644e91..acd51b29a476b 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -12,6 +12,7 @@
#include <linux/string.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
+#include <linux/ethtool_netlink.h>
#include <linux/of_gpio.h>
#include <linux/bitfield.h>
#include <linux/gpio/consumer.h>
@@ -46,6 +47,16 @@
#define AT803X_SMART_SPEED_ENABLE BIT(5)
#define AT803X_SMART_SPEED_RETRY_LIMIT_MASK GENMASK(4, 2)
#define AT803X_SMART_SPEED_BYPASS_TIMER BIT(1)
+#define AT803X_CDT 0x16
+#define AT803X_CDT_MDI_PAIR_MASK GENMASK(9, 8)
+#define AT803X_CDT_ENABLE_TEST BIT(0)
+#define AT803X_CDT_STATUS 0x1c
+#define AT803X_CDT_STATUS_STAT_NORMAL 0
+#define AT803X_CDT_STATUS_STAT_SHORT 1
+#define AT803X_CDT_STATUS_STAT_OPEN 2
+#define AT803X_CDT_STATUS_STAT_FAIL 3
+#define AT803X_CDT_STATUS_STAT_MASK GENMASK(9, 8)
+#define AT803X_CDT_STATUS_DELTA_TIME_MASK GENMASK(7, 0)
#define AT803X_LED_CONTROL 0x18
#define AT803X_DEVICE_ADDR 0x03
@@ -794,12 +805,172 @@ static int at803x_set_tunable(struct phy_device *phydev,
}
}
+static int at803x_cable_test_result_trans(u16 status)
+{
+ switch (FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status)) {
+ case AT803X_CDT_STATUS_STAT_NORMAL:
+ return ETHTOOL_A_CABLE_RESULT_CODE_OK;
+ case AT803X_CDT_STATUS_STAT_SHORT:
+ return ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT;
+ case AT803X_CDT_STATUS_STAT_OPEN:
+ return ETHTOOL_A_CABLE_RESULT_CODE_OPEN;
+ case AT803X_CDT_STATUS_STAT_FAIL:
+ default:
+ return ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC;
+ }
+}
+
+static bool at803x_cdt_test_failed(u16 status)
+{
+ return FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status) ==
+ AT803X_CDT_STATUS_STAT_FAIL;
+}
+
+static bool at803x_cdt_fault_length_valid(u16 status)
+{
+ switch (FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status)) {
+ case AT803X_CDT_STATUS_STAT_OPEN:
+ case AT803X_CDT_STATUS_STAT_SHORT:
+ return true;
+ }
+ return false;
+}
+
+static int at803x_cdt_fault_length(u16 status)
+{
+ int dt;
+
+ /* According to the datasheet the distance to the fault is
+ * DELTA_TIME * 0.824 meters.
+ *
+ * The author suspect the correct formula is:
+ *
+ * fault_distance = DELTA_TIME * (c * VF) / 125MHz / 2
+ *
+ * where c is the speed of light, VF is the velocity factor of
+ * the twisted pair cable, 125MHz the counter frequency and
+ * we need to divide by 2 because the hardware will measure the
+ * round trip time to the fault and back to the PHY.
+ *
+ * With a VF of 0.69 we get the factor 0.824 mentioned in the
+ * datasheet.
+ */
+ dt = FIELD_GET(AT803X_CDT_STATUS_DELTA_TIME_MASK, status);
+
+ return (dt * 824) / 10;
+}
+
+static int at803x_cdt_start(struct phy_device *phydev, int pair)
+{
+ u16 cdt;
+
+ cdt = FIELD_PREP(AT803X_CDT_MDI_PAIR_MASK, pair) |
+ AT803X_CDT_ENABLE_TEST;
+
+ return phy_write(phydev, AT803X_CDT, cdt);
+}
+
+static int at803x_cdt_wait_for_completion(struct phy_device *phydev)
+{
+ int val, ret;
+
+ /* One test run takes about 25ms */
+ ret = phy_read_poll_timeout(phydev, AT803X_CDT, val,
+ !(val & AT803X_CDT_ENABLE_TEST),
+ 30000, 100000, true);
+
+ return ret < 0 ? ret : 0;
+}
+
+static int at803x_cable_test_one_pair(struct phy_device *phydev, int pair)
+{
+ static const int ethtool_pair[] = {
+ ETHTOOL_A_CABLE_PAIR_A,
+ ETHTOOL_A_CABLE_PAIR_B,
+ ETHTOOL_A_CABLE_PAIR_C,
+ ETHTOOL_A_CABLE_PAIR_D,
+ };
+ int ret, val;
+
+ ret = at803x_cdt_start(phydev, pair);
+ if (ret)
+ return ret;
+
+ ret = at803x_cdt_wait_for_completion(phydev);
+ if (ret)
+ return ret;
+
+ val = phy_read(phydev, AT803X_CDT_STATUS);
+ if (val < 0)
+ return val;
+
+ if (at803x_cdt_test_failed(val))
+ return 0;
+
+ ethnl_cable_test_result(phydev, ethtool_pair[pair],
+ at803x_cable_test_result_trans(val));
+
+ if (at803x_cdt_fault_length_valid(val))
+ ethnl_cable_test_fault_length(phydev, ethtool_pair[pair],
+ at803x_cdt_fault_length(val));
+
+ return 1;
+}
+
+static int at803x_cable_test_get_status(struct phy_device *phydev,
+ bool *finished)
+{
+ unsigned long pair_mask = 0xf;
+ int retries = 20;
+ int pair, ret;
+
+ *finished = false;
+
+ /* According to the datasheet the CDT can be performed when
+ * there is no link partner or when the link partner is
+ * auto-negotiating. Starting the test will restart the AN
+ * automatically. It seems that doing this repeatedly we will
+ * get a slot where our link partner won't disturb our
+ * measurement.
+ */
+ while (pair_mask && retries--) {
+ for_each_set_bit(pair, &pair_mask, 4) {
+ ret = at803x_cable_test_one_pair(phydev, pair);
+ if (ret < 0)
+ return ret;
+ if (ret)
+ clear_bit(pair, &pair_mask);
+ }
+ if (pair_mask)
+ msleep(250);
+ }
+
+ *finished = true;
+
+ return 0;
+}
+
+static int at803x_cable_test_start(struct phy_device *phydev)
+{
+ /* Enable auto-negotiation, but advertise no capabilities, no link
+ * will be established. A restart of the auto-negotiation is not
+ * required, because the cable test will automatically break the link.
+ */
+ phy_write(phydev, MII_BMCR, BMCR_ANENABLE);
+ phy_write(phydev, MII_ADVERTISE, ADVERTISE_CSMA);
+ phy_write(phydev, MII_CTRL1000, 0);
+
+ /* we do all the (time consuming) work later */
+ return 0;
+}
+
static struct phy_driver at803x_driver[] = {
{
/* Qualcomm Atheros AR8035 */
.phy_id = ATH8035_PHY_ID,
.name = "Qualcomm Atheros AR8035",
.phy_id_mask = AT803X_PHY_ID_MASK,
+ .flags = PHY_POLL_CABLE_TEST,
.probe = at803x_probe,
.remove = at803x_remove,
.config_init = at803x_config_init,
@@ -814,6 +985,8 @@ static struct phy_driver at803x_driver[] = {
.config_intr = at803x_config_intr,
.get_tunable = at803x_get_tunable,
.set_tunable = at803x_set_tunable,
+ .cable_test_start = at803x_cable_test_start,
+ .cable_test_get_status = at803x_cable_test_get_status,
}, {
/* Qualcomm Atheros AR8030 */
.phy_id = ATH8030_PHY_ID,
@@ -835,6 +1008,7 @@ static struct phy_driver at803x_driver[] = {
.phy_id = ATH8031_PHY_ID,
.name = "Qualcomm Atheros AR8031/AR8033",
.phy_id_mask = AT803X_PHY_ID_MASK,
+ .flags = PHY_POLL_CABLE_TEST,
.probe = at803x_probe,
.remove = at803x_remove,
.config_init = at803x_config_init,
@@ -850,6 +1024,8 @@ static struct phy_driver at803x_driver[] = {
.config_intr = &at803x_config_intr,
.get_tunable = at803x_get_tunable,
.set_tunable = at803x_set_tunable,
+ .cable_test_start = at803x_cable_test_start,
+ .cable_test_get_status = at803x_cable_test_get_status,
}, {
/* Qualcomm Atheros AR8032 */
PHY_ID_MATCH_EXACT(ATH8032_PHY_ID),