From 096516d092d54604d590827d05b1022c8f326639 Mon Sep 17 00:00:00 2001
From: Justin Chen <justin.chen@broadcom.com>
Date: Sat, 12 Aug 2023 21:41:47 -0700
Subject: [PATCH] net: phy: broadcom: stub c45 read/write for 54810
The 54810 does not support c45. The mmd_phy_indirect accesses return
arbirtary values leading to odd behavior like saying it supports EEE
when it doesn't. We also see that reading/writing these non-existent
MMD registers leads to phy instability in some cases.
Fixes: b14995ac2527 ("net: phy: broadcom: Add BCM54810 PHY entry")
Signed-off-by: Justin Chen <justin.chen@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/1691901708-28650-1-git-send-email-justin.chen@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
drivers/net/phy/broadcom.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
index 59cae0d808aa2..04b2e6eeb1952 100644
--- a/drivers/net/phy/broadcom.c
+++ b/drivers/net/phy/broadcom.c
@@ -542,6 +542,17 @@ static int bcm54xx_resume(struct phy_device *phydev)
return bcm54xx_config_init(phydev);
}
+static int bcm54810_read_mmd(struct phy_device *phydev, int devnum, u16 regnum)
+{
+ return -EOPNOTSUPP;
+}
+
+static int bcm54810_write_mmd(struct phy_device *phydev, int devnum, u16 regnum,
+ u16 val)
+{
+ return -EOPNOTSUPP;
+}
+
static int bcm54811_config_init(struct phy_device *phydev)
{
int err, reg;
@@ -1103,6 +1114,8 @@ static struct phy_driver broadcom_drivers[] = {
.get_strings = bcm_phy_get_strings,
.get_stats = bcm54xx_get_stats,
.probe = bcm54xx_phy_probe,
+ .read_mmd = bcm54810_read_mmd,
+ .write_mmd = bcm54810_write_mmd,
.config_init = bcm54xx_config_init,
.config_aneg = bcm5481_config_aneg,
.config_intr = bcm_phy_config_intr,
--
2.30.2