[PATCH v4 2/2] net: phy: realtek: Change TX-delay setting for RGMII modes only

Serge Semin
2019-05-08T21:52:43Z

It's prone to problems if delay is cleared out for other than RGMII
modes. So lets set/clear the TX-delay in the config register only
if actually RGMII-like interface mode is requested. This only
concerns rtl8211f chips.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>

---
Changelog v3
- Accept id and rxid interface mode by clearing the TX_DELAY bit
in this case.

Changelog v4
- Rebase onto net-next
---
drivers/net/phy/realtek.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
index cfbc0ca61123..761ce3b1e7bd 100644
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -161,12 +161,23 @@ static int rtl8211c_config_init(struct phy_device *phydev)

static int rtl8211f_config_init(struct phy_device *phydev)
{
- u16 val = 0;
+ u16 val;

- /* enable TX-delay for rgmii-id and rgmii-txid, otherwise disable it */
- if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
- phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID)
+ /* enable TX-delay for rgmii-{id,txid}, and disable it for rgmii and
+ * rgmii-rxid. The RX-delay can be enabled by the external RXDLY pin.
+ */
+ switch (phydev->interface) {
+ case PHY_INTERFACE_MODE_RGMII:
+ case PHY_INTERFACE_MODE_RGMII_RXID:
+ val = 0;
+ break;
+ case PHY_INTERFACE_MODE_RGMII_ID:
+ case PHY_INTERFACE_MODE_RGMII_TXID:
val = RTL8211F_TX_DELAY;
+ break;
+ default: /* the rest of the modes imply leaving delay as is. */
+ return 0;
+ }

return phy_modify_paged(phydev, 0xd08, 0x11, RTL8211F_TX_DELAY, val);
}
--
2.21.0