[PATCH 3/4] lan78xx: Read LED modes from Device Tree

[Phil Elwell]

Add support for DT property "microchip,led-modes", a vector of two
cells (u32s) in the range 0-15, each of which sets the mode for one
of the two LEDs. Some possible values are:

    0=link/activity          1=link1000/activity
    2=link100/activity       3=link10/activity
    4=link100/1000/activity  5=link10/1000/activity
    6=link10/100/activity    14=off    15=on

Also use the presence of the DT property to indicate that the
LEDs should be enabled - necessary in the event that no valid OTP
or EEPROM is available.

Signed-off-by: Phil Elwell <p...@raspberrypi.org>
---
 drivers/net/usb/lan78xx.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index d98397b..ffb483d 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2008,6 +2008,7 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
 {
        int ret;
        u32 mii_adv;
+       u32 led_modes[2];
        struct phy_device *phydev;
 
        phydev = phy_find_first(dev->mdiobus);
@@ -2097,6 +2098,25 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
                (void)lan78xx_set_eee(dev->net, &edata);
        }
 
+       if (!of_property_read_u32_array(dev->udev->dev.of_node,
+                                       "microchip,led-modes",
+                                       led_modes, ARRAY_SIZE(led_modes))) {
+               u32 reg;
+               int i;
+
+               reg = phy_read(phydev, 0x1d);
+               for (i = 0; i < ARRAY_SIZE(led_modes); i++) {
+                       reg &= ~(0xf << (i * 4));
+                       reg |= (led_modes[i] & 0xf) << (i * 4);
+               }
+               (void)phy_write(phydev, 0x1d, reg);
+
+               /* Ensure the LEDs are enabled */
+               lan78xx_read_reg(dev, HW_CFG, &reg);
+               reg |= HW_CFG_LED0_EN_ | HW_CFG_LED1_EN_;
+               lan78xx_write_reg(dev, HW_CFG, reg);
+       }
+
        genphy_config_aneg(phydev);
 
        dev->fc_autoneg = phydev->autoneg;
-- 
2.7.4