[PATCH net-next 3/3] net: phy: dp83867: Add support for amplitude graph

[João Rodrigues]

Output the raw information of each segment.
Each segment also comes with the distance information,
but this does not map to the current output.

Signed-off-by: João Rodrigues <jrodrigues@xxxxxxxxxx>
---
 drivers/net/phy/dp83867.c | 86 ++++++++++++++++++++++++++++++++++++---
 1 file changed, 80 insertions(+), 6 deletions(-)

diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
index ff8c97a29195..e56a892d3da7 100644
--- a/drivers/net/phy/dp83867.c
+++ b/drivers/net/phy/dp83867.c
@@ -54,6 +54,8 @@
 #define DP83867_RXFSOP2	0x013A
 #define DP83867_RXFSOP3	0x013B
 #define DP83867_IO_MUX_CFG	0x0170
+#define DP83867_TDR_GEN_CFG2	0x0181
+#define DP83867_TDR_GEN_CFG4	0x0185
 #define DP83867_TDR_GEN_CFG5	0x0186
 #define DP83867_TDR_GEN_CFG6	0x0187
 #define DP83867_TDR_GEN_CFG7	0x0189
@@ -223,6 +225,8 @@ struct dp83867_private {
 	bool set_clk_output;
 	u32 clk_output_sel;
 	bool sgmii_ref_clk_en;
+	bool cable_test_tdr;
+	s8 pair;
 };
 
 /* Register values are converted to SNR(dB) as suggested by
@@ -1068,7 +1072,7 @@ static u32 dp83867_cycles2cm(u32 cycles)
 	return cycles * 8 * 20;
 }
 
-static int dp83867_cable_test_start(struct phy_device *phydev)
+static int dp83867_cable_test_common(struct phy_device *phydev)
 {
 	int ret;
 
@@ -1082,11 +1086,38 @@ static int dp83867_cable_test_start(struct phy_device *phydev)
 	if (ret < 0)
 		return ret;
 
-	ret = phy_write_mmd(phydev, DP83867_DEVADDR, DP83867_TDR_GEN_CFG5,
-			    DP83867_TDR_GEN_CFG5_FLAGS);
+	return phy_write_mmd(phydev, DP83867_DEVADDR, DP83867_TDR_GEN_CFG5,
+			     DP83867_TDR_GEN_CFG5_FLAGS);
+}
+
+static int dp83867_cable_test_start(struct phy_device *phydev)
+{
+	struct dp83867_private *priv = phydev->priv;
+	int ret;
+
+	ret = dp83867_cable_test_common(phydev);
+	if (ret < 0)
+		return ret;
+
+	priv->cable_test_tdr = false;
+
+	return phy_write_mmd(phydev, DP83867_DEVADDR, DP83867_CFG3,
+			     DP83867_TDR_START);
+}
+
+static int dp83867_cable_test_tdr_start(struct phy_device *phydev,
+					const struct phy_tdr_config *cfg)
+{
+	struct dp83867_private *priv = phydev->priv;
+	int ret;
+
+	ret = dp83867_cable_test_common(phydev);
 	if (ret < 0)
 		return ret;
 
+	priv->cable_test_tdr = true;
+	priv->pair = cfg->pair;
+
 	return phy_write_mmd(phydev, DP83867_DEVADDR, DP83867_CFG3,
 			     DP83867_TDR_START);
 }
@@ -1105,9 +1136,14 @@ static int dp83867_cable_test_report_trans(struct phy_device *phydev, s8 pair,
 
 	for (i = number_peaks; i >= 0; --i) {
 		if (peak_value[i] > threshold) {
-			fault_location =
-				dp83867_cycles2cm(peak_location[i] -
+			if (peak_location[i] >= DP83867_TDR_OFFSET) {
+				fault_location = dp83867_cycles2cm(peak_location[i] -
 					DP83867_TDR_OFFSET) / 2;
+			} else {
+				phydev_dbg(phydev, "Returned TDR fault location is too low");
+				fault_location = dp83867_cycles2cm(peak_location[i]) / 2;
+			}
+
 			if (peak_sign[i] == 1) {
 				fault_rslt =
 					ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT;
@@ -1208,6 +1244,39 @@ static int dp83867_read_tdr_registers(struct phy_device *phydev, s8 pair,
 	return 0;
 }
 
+static int dp83867_simplified_amplitude_graph(struct phy_device *phydev)
+{
+	struct dp83867_private *priv = phydev->priv;
+	int peak_sign[5];
+	int peak_loc[ARRAY_SIZE(peak_sign)];
+	int peak_val[ARRAY_SIZE(peak_sign)];
+	int i;
+	int mV;
+	int ret;
+	s8 pair;
+
+	for (pair = ETHTOOL_A_CABLE_PAIR_A; pair <= ETHTOOL_A_CABLE_PAIR_D;
+			pair++) {
+		if (priv->pair != PHY_PAIR_ALL && pair != priv->pair)
+			continue;
+
+		ret = dp83867_read_tdr_registers(phydev, pair, peak_loc,
+						 peak_val, peak_sign,
+						 ARRAY_SIZE(peak_sign));
+		if (ret < 0)
+			return ret;
+
+		for (i = 0; i < ARRAY_SIZE(peak_loc); i++) {
+			mV = peak_val[i];
+			if (peak_sign[i])
+				mV *= -1;
+
+			ethnl_cable_test_amplitude(phydev, pair, mV);
+		}
+	}
+	return 0;
+}
+
 static int dp83867_cable_test_report_pair(struct phy_device *phydev, s8 pair)
 {
 	int peak_sign[5];
@@ -1242,6 +1311,7 @@ static int dp83867_cable_test_report(struct phy_device *phydev)
 static int dp83867_cable_test_get_status(struct phy_device *phydev,
 					 bool *finished)
 {
+	struct dp83867_private *priv = phydev->priv;
 	int ret;
 
 	*finished = false;
@@ -1258,7 +1328,10 @@ static int dp83867_cable_test_get_status(struct phy_device *phydev,
 	if (ret & DP83867_TDR_FAIL)
 		return -EBUSY;
 
-	return dp83867_cable_test_report(phydev);
+	if (priv->cable_test_tdr)
+		return dp83867_simplified_amplitude_graph(phydev);
+	else
+		return dp83867_cable_test_report(phydev);
 }
 
 static int dp83867_get_sqi(struct phy_device *phydev)
@@ -1478,6 +1551,7 @@ static struct phy_driver dp83867_driver[] = {
 		.set_loopback	= dp83867_loopback,
 
 		.cable_test_start	= dp83867_cable_test_start,
+		.cable_test_tdr_start	= dp83867_cable_test_tdr_start,
 		.cable_test_get_status	= dp83867_cable_test_get_status,
 
 		.led_brightness_set = dp83867_led_brightness_set,
-- 
2.25.1