diff mbox series

[net-next,v3,1/3] net: phy: dp83td510: add SQI support

Message ID 20220608123236.792405-2-o.rempel@pengutronix.de (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series net: phy: dp83td510: add cable diag support | expand

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Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 1 maintainers not CCed: linux@armlinux.org.uk
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 67 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Oleksij Rempel June 8, 2022, 12:32 p.m. UTC 
Convert MSE (mean-square error) values to SNR and split it SQI (Signal Quality
Indicator) ranges. The used ranges are taken from "OPEN ALLIANCE - Advanced
diagnostic features for 100BASE-T1 automotive Ethernet PHYs"
specification.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 drivers/net/phy/dp83td510.c | 49 +++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

Comments

Andrew Lunn June 11, 2022, 3:08 p.m. UTC | #1 
On Wed, Jun 08, 2022 at 02:32:34PM +0200, Oleksij Rempel wrote:
> Convert MSE (mean-square error) values to SNR and split it SQI (Signal Quality
> Indicator) ranges. The used ranges are taken from "OPEN ALLIANCE - Advanced
> diagnostic features for 100BASE-T1 automotive Ethernet PHYs"
> specification.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew
diff mbox series

Patch

diff --git a/drivers/net/phy/dp83td510.c b/drivers/net/phy/dp83td510.c
index 1ae792b0daaa..3cd9a77f9532 100644
--- a/drivers/net/phy/dp83td510.c
+++ b/drivers/net/phy/dp83td510.c
@@ -27,6 +27,27 @@ 
 #define DP83TD510E_AN_STAT_1			0x60c
 #define DP83TD510E_MASTER_SLAVE_RESOL_FAIL	BIT(15)
 
+#define DP83TD510E_MSE_DETECT			0xa85
+
+#define DP83TD510_SQI_MAX	7
+
+/* Register values are converted to SNR(dB) as suggested by
+ * "Application Report - DP83TD510E Cable Diagnostics Toolkit":
+ * SNR(dB) = -10 * log10 (VAL/2^17) - 1.76 dB.
+ * SQI ranges are implemented according to "OPEN ALLIANCE - Advanced diagnostic
+ * features for 100BASE-T1 automotive Ethernet PHYs"
+ */
+static const u16 dp83td510_mse_sqi_map[] = {
+	0x0569, /* < 18dB */
+	0x044c, /* 18dB =< SNR < 19dB */
+	0x0369, /* 19dB =< SNR < 20dB */
+	0x02b6, /* 20dB =< SNR < 21dB */
+	0x0227, /* 21dB =< SNR < 22dB */
+	0x01b6, /* 22dB =< SNR < 23dB */
+	0x015b, /* 23dB =< SNR < 24dB */
+	0x0000  /* 24dB =< SNR */
+};
+
 static int dp83td510_config_intr(struct phy_device *phydev)
 {
 	int ret;
@@ -164,6 +185,32 @@  static int dp83td510_config_aneg(struct phy_device *phydev)
 	return genphy_c45_check_and_restart_aneg(phydev, changed);
 }
 
+static int dp83td510_get_sqi(struct phy_device *phydev)
+{
+	int sqi, ret;
+	u16 mse_val;
+
+	if (!phydev->link)
+		return 0;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TD510E_MSE_DETECT);
+	if (ret < 0)
+		return ret;
+
+	mse_val = 0xFFFF & ret;
+	for (sqi = 0; sqi < ARRAY_SIZE(dp83td510_mse_sqi_map); sqi++) {
+		if (mse_val >= dp83td510_mse_sqi_map[sqi])
+			return sqi;
+	}
+
+	return -EINVAL;
+}
+
+static int dp83td510_get_sqi_max(struct phy_device *phydev)
+{
+	return DP83TD510_SQI_MAX;
+}
+
 static int dp83td510_get_features(struct phy_device *phydev)
 {
 	/* This PHY can't respond on MDIO bus if no RMII clock is enabled.
@@ -192,6 +239,8 @@  static struct phy_driver dp83td510_driver[] = {
 	.get_features	= dp83td510_get_features,
 	.config_intr	= dp83td510_config_intr,
 	.handle_interrupt = dp83td510_handle_interrupt,
+	.get_sqi	= dp83td510_get_sqi,
+	.get_sqi_max	= dp83td510_get_sqi_max,
 
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,