net: dsa: microchip: Do not execute PTP driver code for unsupported switches

[ Upstream commit 6ed3472173c575cd8aaed6c62eb74f7728404ee6 ]

The PTP driver code only works for certain KSZ switches like KSZ9477,
KSZ9567, LAN937X and their varieties.  This code is enabled by kernel
configuration CONFIG_NET_DSA_MICROCHIP_KSZ_PTP.  As the DSA driver is
common to work with all KSZ switches this PTP code is not appropriate
for other unsupported switches.  The ptp_capable indication is added to
the chip data structure to signal whether to execute those code.

Signed-off-by: Tristram Ha <tristram.ha@microchip.com>
Link: https://patch.msgid.link/20241218020240.70601-1-Tristram.Ha@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 0f80e21bf622 ("net: dsa: microchip: Free previously initialized ports on init failures")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/dsa/microchip/ksz_common.c

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 6ae5ad3..010f267 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -1342,6 +1342,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 		.supports_rgmii = {false, false, true},
 		.internal_phy = {true, true, false},
 		.gbit_capable = {false, false, true},
+		.ptp_capable = true,
 		.wr_table = &ksz8563_register_set,
 		.rd_table = &ksz8563_register_set,
 	},
@@ -1553,6 +1554,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 		.internal_phy	= {true, true, true, true,
 				   true, false, false},
 		.gbit_capable	= {true, true, true, true, true, true, true},
+		.ptp_capable = true,
 		.wr_table = &ksz9477_register_set,
 		.rd_table = &ksz9477_register_set,
 	},
@@ -1680,6 +1682,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 		.supports_rgmii = {false, false, true},
 		.internal_phy = {true, true, false},
 		.gbit_capable = {true, true, true},
+		.ptp_capable = true,
 	},
 
 	[KSZ8567] = {
@@ -1715,6 +1718,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 				   true, false, false},
 		.gbit_capable	= {false, false, false, false, false,
 				   true, true},
+		.ptp_capable = true,
 	},
 
 	[KSZ9567] = {
@@ -1747,6 +1751,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 		.internal_phy	= {true, true, true, true,
 				   true, false, false},
 		.gbit_capable	= {true, true, true, true, true, true, true},
+		.ptp_capable = true,
 	},
 
 	[LAN9370] = {
@@ -1775,6 +1780,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 		.supports_rmii = {false, false, false, false, true},
 		.supports_rgmii = {false, false, false, false, true},
 		.internal_phy = {true, true, true, true, false},
+		.ptp_capable = true,
 	},
 
 	[LAN9371] = {
@@ -1803,6 +1809,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 		.supports_rmii = {false, false, false, false, true, true},
 		.supports_rgmii = {false, false, false, false, true, true},
 		.internal_phy = {true, true, true, true, false, false},
+		.ptp_capable = true,
 	},
 
 	[LAN9372] = {
@@ -1835,6 +1842,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 				   true, true, false, false},
 		.internal_phy	= {true, true, true, true,
 				   false, false, true, true},
+		.ptp_capable = true,
 	},
 
 	[LAN9373] = {
@@ -1867,6 +1875,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 				   true, true, false, false},
 		.internal_phy	= {true, true, true, false,
 				   false, false, true, true},
+		.ptp_capable = true,
 	},
 
 	[LAN9374] = {
@@ -1899,6 +1908,7 @@ const struct ksz_chip_data ksz_switch_chips[] = {
 				   true, true, false, false},
 		.internal_phy	= {true, true, true, true,
 				   false, false, true, true},
+		.ptp_capable = true,
 	},
 };
 EXPORT_SYMBOL_GPL(ksz_switch_chips);
@@ -2556,16 +2566,21 @@ static int ksz_setup(struct dsa_switch *ds)
 			if (ret)
 				goto out_girq;
 
-			ret = ksz_ptp_irq_setup(ds, dp->index);
-			if (ret)
-				goto out_pirq;
+			if (dev->info->ptp_capable) {
+				ret = ksz_ptp_irq_setup(ds, dp->index);
+				if (ret)
+					goto out_pirq;
+			}
 		}
 	}
 
-	ret = ksz_ptp_clock_register(ds);
-	if (ret) {
-		dev_err(dev->dev, "Failed to register PTP clock: %d\n", ret);
-		goto out_ptpirq;
+	if (dev->info->ptp_capable) {
+		ret = ksz_ptp_clock_register(ds);
+		if (ret) {
+			dev_err(dev->dev, "Failed to register PTP clock: %d\n",
+				ret);
+			goto out_ptpirq;
+		}
 	}
 
 	ret = ksz_mdio_register(dev);
@@ -2585,9 +2600,10 @@ static int ksz_setup(struct dsa_switch *ds)
 	return 0;
 
 out_ptp_clock_unregister:
-	ksz_ptp_clock_unregister(ds);
+	if (dev->info->ptp_capable)
+		ksz_ptp_clock_unregister(ds);
 out_ptpirq:
-	if (dev->irq > 0)
+	if (dev->irq > 0 && dev->info->ptp_capable)
 		dsa_switch_for_each_user_port(dp, dev->ds)
 			ksz_ptp_irq_free(ds, dp->index);
 out_pirq:
@@ -2606,11 +2622,13 @@ static void ksz_teardown(struct dsa_switch *ds)
 	struct ksz_device *dev = ds->priv;
 	struct dsa_port *dp;
 
-	ksz_ptp_clock_unregister(ds);
+	if (dev->info->ptp_capable)
+		ksz_ptp_clock_unregister(ds);
 
 	if (dev->irq > 0) {
 		dsa_switch_for_each_user_port(dp, dev->ds) {
-			ksz_ptp_irq_free(ds, dp->index);
+			if (dev->info->ptp_capable)
+				ksz_ptp_irq_free(ds, dp->index);
 
 			ksz_irq_free(&dev->ports[dp->index].pirq);
 		}

drivers/net/dsa/microchip/ksz_common.h

diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 4ee518f..36f2fd7 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -86,6 +86,7 @@ struct ksz_chip_data {
 	bool supports_rgmii[KSZ_MAX_NUM_PORTS];
 	bool internal_phy[KSZ_MAX_NUM_PORTS];
 	bool gbit_capable[KSZ_MAX_NUM_PORTS];
+	bool ptp_capable;
 	const struct regmap_access_table *wr_table;
 	const struct regmap_access_table *rd_table;
 };