[PATCH v2] net: phy: DP83822: enable rgmii mode if phy_interface_is_rgmii

[Tommaso Merciai]

RGMII mode can be enable from dp83822 straps, and also writing bit 9
of register 0x17 - RMII and Status Register (RCSR).
When phy_interface_is_rgmii rgmii mode must be enabled, same for
contrary, this prevents malconfigurations of hw straps

References:
 - https://www.ti.com/lit/gpn/dp83822i p66

Signed-off-by: Tommaso Merciai <tommaso.merciai@xxxxxxxxxxxxxxxxxxxx>
Co-developed-by: Michael Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx>
Suggested-by: Alberto Bianchi <alberto.bianchi@xxxxxxxxxxxxxxxxxxxx>
Tested-by: Tommaso Merciai <tommaso.merciai@xxxxxxxxxxxxxxxxxxxx>
---
Changes since v1:
 - Improve commit msg
 - Add definition of bit 9 reg rcsr (rgmii mode en)
 - Handle case: phy_interface_is_rgmii is false

 drivers/net/phy/dp83822.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/net/phy/dp83822.c b/drivers/net/phy/dp83822.c
index ce17b2af3218..7cb9d084707b 100644
--- a/drivers/net/phy/dp83822.c
+++ b/drivers/net/phy/dp83822.c
@@ -94,6 +94,9 @@
 #define DP83822_WOL_INDICATION_SEL BIT(8)
 #define DP83822_WOL_CLR_INDICATION BIT(11)
 
+/* RCSR bits */
+#define DP83822_RGMII_MODE_EN	BIT(9)
+
 /* RSCR bits */
 #define DP83822_RX_CLK_SHIFT	BIT(12)
 #define DP83822_TX_CLK_SHIFT	BIT(11)
@@ -408,6 +411,12 @@ static int dp83822_config_init(struct phy_device *phydev)
 			if (err)
 				return err;
 		}
+
+		phy_set_bits_mmd(phydev, DP83822_DEVADDR,
+					MII_DP83822_RCSR, DP83822_RGMII_MODE_EN);
+	} else {
+		phy_clear_bits_mmd(phydev, DP83822_DEVADDR,
+					MII_DP83822_RCSR, DP83822_RGMII_MODE_EN);
 	}
 
 	if (dp83822->fx_enabled) {
-- 
2.25.1