[PATCH net-next 1/2] net:dsa:microchip: add property to select internal RMII reference clock

[Ante Knezic]

Microchip KSZ8863/KSZ8873 have the ability to select between internal
and external RMII reference clock. By default, reference clock
needs to be provided via REFCLKI_3 pin. If required, device can be
setup to provide RMII clock internally so that REFCLKI_3 pin can be
left unconnected.
Add a new "microchip,rmii-clk-internal" property which will set
RMII clock reference to internal.

Signed-off-by: Ante Knezic <ante.knezic@xxxxxxxxxxx>
---
 drivers/net/dsa/microchip/ksz8795.c     | 4 ++++
 drivers/net/dsa/microchip/ksz8795_reg.h | 3 +++
 drivers/net/dsa/microchip/ksz_common.c  | 3 +++
 drivers/net/dsa/microchip/ksz_common.h  | 1 +
 4 files changed, 11 insertions(+)

diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c
index 91aba470fb2f..c5df571153ab 100644
--- a/drivers/net/dsa/microchip/ksz8795.c
+++ b/drivers/net/dsa/microchip/ksz8795.c
@@ -1434,6 +1434,10 @@ int ksz8_setup(struct dsa_switch *ds)
 	for (i = 0; i < (dev->info->num_vlans / 4); i++)
 		ksz8_r_vlan_entries(dev, i);
 
+	if (ksz_is_ksz88x3(dev) && dev->rmii_clk_internal)
+		ksz_cfg(dev, KSZ8863_REG_FVID_AND_HOST_MODE,
+			KSZ8863_PORT3_RMII_CLK_INTERNAL, true);
+
 	return ksz8_handle_global_errata(ds);
 }
 
diff --git a/drivers/net/dsa/microchip/ksz8795_reg.h b/drivers/net/dsa/microchip/ksz8795_reg.h
index 7a57c6088f80..0a3fff7d6d32 100644
--- a/drivers/net/dsa/microchip/ksz8795_reg.h
+++ b/drivers/net/dsa/microchip/ksz8795_reg.h
@@ -22,6 +22,9 @@
 #define KSZ8863_GLOBAL_SOFTWARE_RESET	BIT(4)
 #define KSZ8863_PCS_RESET		BIT(0)
 
+#define KSZ8863_REG_FVID_AND_HOST_MODE  0xC6
+#define KSZ8863_PORT3_RMII_CLK_INTERNAL BIT(3)
+
 #define REG_SW_CTRL_0			0x02
 
 #define SW_NEW_BACKOFF			BIT(7)
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 6673122266b7..dc8cf59c6dd9 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3631,6 +3631,9 @@ int ksz_switch_register(struct ksz_device *dev)
 		}
 	}
 
+	dev->rmii_clk_internal = of_property_read_bool(dev->dev->of_node,
+						       "microchip,rmii-clk-internal");
+
 	ret = dsa_register_switch(dev->ds);
 	if (ret) {
 		dev->dev_ops->exit(dev);
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index a4de58847dea..54589736398a 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -157,6 +157,7 @@ struct ksz_device {
 	phy_interface_t compat_interface;
 	bool synclko_125;
 	bool synclko_disable;
+	bool rmii_clk_internal;
 
 	struct vlan_table *vlan_cache;
 
-- 
2.11.0