[PATCH v4 net-next 3/5] drivers/net/phy: add connection between ethtool and phylib for PLCA

[Piergiorgio Beruto]

This patch adds the required connection between netlink ethtool and
phylib to resolve PLCA get/set config and get status messages.

Signed-off-by: Piergiorgio Beruto <piergiorgio.beruto@xxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
---
 drivers/net/phy/phy.c        | 192 +++++++++++++++++++++++++++++++++++
 drivers/net/phy/phy_device.c |   3 +
 include/linux/phy.h          |   7 ++
 3 files changed, 202 insertions(+)

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index e5b6cb1a77f9..3378ca4f49b6 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -543,6 +543,198 @@ int phy_ethtool_get_stats(struct phy_device *phydev,
 }
 EXPORT_SYMBOL(phy_ethtool_get_stats);
 
+/**
+ * phy_ethtool_get_plca_cfg - Get PLCA RS configuration
+ * @phydev: the phy_device struct
+ * @plca_cfg: where to store the retrieved configuration
+ *
+ * Retrieve the PLCA configuration from the PHY. Return 0 on success or a
+ * negative value if an error occurred.
+ */
+int phy_ethtool_get_plca_cfg(struct phy_device *phydev,
+			     struct phy_plca_cfg *plca_cfg)
+{
+	int ret;
+
+	if (!phydev->drv) {
+		ret = -EIO;
+		goto out;
+	}
+
+	if (!phydev->drv->get_plca_cfg) {
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
+
+	mutex_lock(&phydev->lock);
+	ret = phydev->drv->get_plca_cfg(phydev, plca_cfg);
+
+	mutex_unlock(&phydev->lock);
+out:
+	return ret;
+}
+
+/**
+ * plca_check_valid - Check PLCA configuration before enabling
+ * @phydev: the phy_device struct
+ * @plca_cfg: current PLCA configuration
+ * @extack: extack for reporting useful error messages
+ *
+ * Checks whether the PLCA and PHY configuration are consistent and it is safe
+ * to enable PLCA. Returns 0 on success or a negative value if the PLCA or PHY
+ * configuration is not consistent.
+ */
+static int plca_check_valid(struct phy_device *phydev,
+			    const struct phy_plca_cfg *plca_cfg,
+			    struct netlink_ext_ack *extack)
+{
+	int ret = 0;
+
+	if (!linkmode_test_bit(ETHTOOL_LINK_MODE_10baseT1S_P2MP_Half_BIT,
+			       phydev->advertising)) {
+		ret = -EOPNOTSUPP;
+		NL_SET_ERR_MSG(extack,
+			       "Point to Multi-Point mode is not enabled");
+	} else if (plca_cfg->node_id >= 255) {
+		NL_SET_ERR_MSG(extack, "PLCA node ID is not set");
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+/**
+ * phy_ethtool_set_plca_cfg - Set PLCA RS configuration
+ * @phydev: the phy_device struct
+ * @plca_cfg: new PLCA configuration to apply
+ * @extack: extack for reporting useful error messages
+ *
+ * Sets the PLCA configuration in the PHY. Return 0 on success or a
+ * negative value if an error occurred.
+ */
+int phy_ethtool_set_plca_cfg(struct phy_device *phydev,
+			     const struct phy_plca_cfg *plca_cfg,
+			     struct netlink_ext_ack *extack)
+{
+	struct phy_plca_cfg *curr_plca_cfg;
+	int ret;
+
+	if (!phydev->drv) {
+		ret = -EIO;
+		goto out;
+	}
+
+	if (!phydev->drv->set_plca_cfg ||
+	    !phydev->drv->get_plca_cfg) {
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
+
+	curr_plca_cfg = kmalloc(sizeof(*curr_plca_cfg), GFP_KERNEL);
+	if (!curr_plca_cfg) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	mutex_lock(&phydev->lock);
+
+	ret = phydev->drv->get_plca_cfg(phydev, curr_plca_cfg);
+	if (ret)
+		goto out_drv;
+
+	if (curr_plca_cfg->enabled < 0 && plca_cfg->enabled >= 0) {
+		NL_SET_ERR_MSG(extack,
+			       "PHY does not support changing the PLCA 'enable' attribute");
+		ret = -EINVAL;
+		goto out_drv;
+	}
+
+	if (curr_plca_cfg->node_id < 0 && plca_cfg->node_id >= 0) {
+		NL_SET_ERR_MSG(extack,
+			       "PHY does not support changing the PLCA 'local node ID' attribute");
+		ret = -EINVAL;
+		goto out_drv;
+	}
+
+	if (curr_plca_cfg->node_cnt < 0 && plca_cfg->node_cnt >= 0) {
+		NL_SET_ERR_MSG(extack,
+			       "PHY does not support changing the PLCA 'node count' attribute");
+		ret = -EINVAL;
+		goto out_drv;
+	}
+
+	if (curr_plca_cfg->to_tmr < 0 && plca_cfg->to_tmr >= 0) {
+		NL_SET_ERR_MSG(extack,
+			       "PHY does not support changing the PLCA 'TO timer' attribute");
+		ret = -EINVAL;
+		goto out_drv;
+	}
+
+	if (curr_plca_cfg->burst_cnt < 0 && plca_cfg->burst_cnt >= 0) {
+		NL_SET_ERR_MSG(extack,
+			       "PHY does not support changing the PLCA 'burst count' attribute");
+		ret = -EINVAL;
+		goto out_drv;
+	}
+
+	if (curr_plca_cfg->burst_tmr < 0 && plca_cfg->burst_tmr >= 0) {
+		NL_SET_ERR_MSG(extack,
+			       "PHY does not support changing the PLCA 'burst timer' attribute");
+		ret = -EINVAL;
+		goto out_drv;
+	}
+
+	// if enabling PLCA, perform a few sanity checks
+	if (plca_cfg->enabled > 0) {
+		// allow setting node_id concurrently with enabled
+		if (plca_cfg->node_id >= 0)
+			curr_plca_cfg->node_id = plca_cfg->node_id;
+
+		ret = plca_check_valid(phydev, curr_plca_cfg, extack);
+		if (ret)
+			goto out_drv;
+	}
+
+	ret = phydev->drv->set_plca_cfg(phydev, plca_cfg);
+
+out_drv:
+	kfree(curr_plca_cfg);
+	mutex_unlock(&phydev->lock);
+out:
+	return ret;
+}
+
+/**
+ * phy_ethtool_get_plca_status - Get PLCA RS status information
+ * @phydev: the phy_device struct
+ * @plca_st: where to store the retrieved status information
+ *
+ * Retrieve the PLCA status information from the PHY. Return 0 on success or a
+ * negative value if an error occurred.
+ */
+int phy_ethtool_get_plca_status(struct phy_device *phydev,
+				struct phy_plca_status *plca_st)
+{
+	int ret;
+
+	if (!phydev->drv) {
+		ret = -EIO;
+		goto out;
+	}
+
+	if (!phydev->drv->get_plca_status) {
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
+
+	mutex_lock(&phydev->lock);
+	ret = phydev->drv->get_plca_status(phydev, plca_st);
+
+	mutex_unlock(&phydev->lock);
+out:
+	return ret;
+}
+
 /**
  * phy_start_cable_test - Start a cable test
  *
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 8e48b3cec5e7..44bd06be9691 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -3276,6 +3276,9 @@ static const struct ethtool_phy_ops phy_ethtool_phy_ops = {
 	.get_sset_count		= phy_ethtool_get_sset_count,
 	.get_strings		= phy_ethtool_get_strings,
 	.get_stats		= phy_ethtool_get_stats,
+	.get_plca_cfg		= phy_ethtool_get_plca_cfg,
+	.set_plca_cfg		= phy_ethtool_set_plca_cfg,
+	.get_plca_status	= phy_ethtool_get_plca_status,
 	.start_cable_test	= phy_start_cable_test,
 	.start_cable_test_tdr	= phy_start_cable_test_tdr,
 };
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 1e87d3f05209..bcaf1dfd0687 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1846,6 +1846,13 @@ int phy_ethtool_get_strings(struct phy_device *phydev, u8 *data);
 int phy_ethtool_get_sset_count(struct phy_device *phydev);
 int phy_ethtool_get_stats(struct phy_device *phydev,
 			  struct ethtool_stats *stats, u64 *data);
+int phy_ethtool_get_plca_cfg(struct phy_device *phydev,
+			     struct phy_plca_cfg *plca_cfg);
+int phy_ethtool_set_plca_cfg(struct phy_device *phydev,
+			     const struct phy_plca_cfg *plca_cfg,
+			     struct netlink_ext_ack *extack);
+int phy_ethtool_get_plca_status(struct phy_device *phydev,
+				struct phy_plca_status *plca_st);
 
 static inline int phy_package_read(struct phy_device *phydev, u32 regnum)
 {
-- 
2.37.4