[PATCH net] net: phy: dp83867: handle the active-high LED polarity mode

[Donggeun Yoo]

Commit a274465cc3be ("net: phy: support 'active-high' property for PHY
LEDs") added PHY_LED_ACTIVE_HIGH and made of_phy_led() set the matching
bit in the modes mask when a LED node carries the 'active-high'
property. dp83867 was not part of that series.

dp83867_led_polarity_set() only recognizes PHY_LED_ACTIVE_LOW, so
PHY_LED_ACTIVE_HIGH falls through to the default case and returns -EINVAL.
of_phy_led() propagates the error, of_phy_leds() drops the LEDs registered
so far and passes it on, and phy_probe() fails. A device tree marking a
DP83867 LED as 'active-high', which leds/common.yaml allows and
ethernet-phy.yaml references for led@N nodes, thus stops the PHY from
probing.

Active high is what the function programs when no polarity mode is
requested at all, so the initial value of polarity already satisfies the
request and only the case label is missing.

The same series updated mxl-gpy in commit eb89c79c1b8f ("net: phy:
mxl-gpy: correctly describe LED polarity") and aquantia in
commit 9d55e68b19f2 ("net: phy: aquantia: correctly describe LED
polarity override").

Fixes: a274465cc3be ("net: phy: support 'active-high' property for PHY LEDs")
Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@xxxxxxxxx>
---
Compile tested only. I have no DP83867 hardware, so the failure path was
traced by inspection through of_phy_led(), of_phy_leds() and phy_probe().

The polarity bit sense assumed here matches the datasheet: LEDCR2 bits
2, 6, 10 and 14 are LED_x_POLARITY with 1 = active high, 0 = active low,
and they reset to 1 (SNLS484J, Table 8-24).

 drivers/net/phy/dp83867.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
index 88255e92b4cd..61a941aa02d9 100644
--- a/drivers/net/phy/dp83867.c
+++ b/drivers/net/phy/dp83867.c
@@ -1150,6 +1150,9 @@ static int dp83867_led_polarity_set(struct phy_device *phydev, int index,
 		case PHY_LED_ACTIVE_LOW:
 			polarity = 0;
 			break;
+		case PHY_LED_ACTIVE_HIGH:
+			polarity = DP83867_LED_POLARITY(index);
+			break;
 		default:
 			return -EINVAL;
 		}

base-commit: 5a3f7a683aee56e1f15c9d53041f3236767eaae7
-- 
2.53.0