Read boolean Device Tree property "maxlinear,rmii-refclk-out" and switch
the RMII reference clock to be a clock output rather than an input if it
is set.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
---
v4: set GSWIP_MII_CFG_RMII_CLK bit in RMII case inside the switch
    statement instead of a (wrong) if-clause just below

 drivers/net/dsa/lantiq/lantiq_gswip_common.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/dsa/lantiq/lantiq_gswip_common.c b/drivers/net/dsa/lantiq/lantiq_gswip_common.c
index f6846060fa18..6a4a09ebdd33 100644
--- a/drivers/net/dsa/lantiq/lantiq_gswip_common.c
+++ b/drivers/net/dsa/lantiq/lantiq_gswip_common.c
@@ -1433,6 +1433,8 @@ static void gswip_phylink_mac_config(struct phylink_config *config,
 		break;
 	case PHY_INTERFACE_MODE_RMII:
 		miicfg |= GSWIP_MII_CFG_MODE_RMIIM;
+		if (of_property_read_bool(dp->dn, "maxlinear,rmii-refclk-out"))
+			miicfg |= GSWIP_MII_CFG_RMII_CLK;
 		break;
 	case PHY_INTERFACE_MODE_RGMII:
 	case PHY_INTERFACE_MODE_RGMII_ID:
-- 
2.51.2