From 7b103aaf0d564b83ee1d4bb532ee7ae36ed001ed Mon Sep 17 00:00:00 2001 From: Daniel Golle Date: Tue, 9 Dec 2025 01:29:34 +0000 Subject: [PATCH] net: dsa: mxl-gsw1xx: manually clear RANEG bit Despite being documented as self-clearing, the RANEG bit sometimes remains set, preventing auto-negotiation from happening. Manually clear the RANEG bit after 10ms as advised by MaxLinear. In order to not hold RTNL during the 10ms of waiting schedule delayed work to take care of clearing the bit asynchronously, which is similar to the self-clearing behavior. Fixes: 22335939ec90 ("net: dsa: add driver for MaxLinear GSW1xx switch family") Reported-by: Rasmus Villemoes Signed-off-by: Daniel Golle Link: https://patch.msgid.link/76745fceb5a3f53088110fb7a96acf88434088ca.1765241054.git.daniel@makrotopia.org Reviewed-by: Vladimir Oltean Signed-off-by: Paolo Abeni --- drivers/net/dsa/lantiq/mxl-gsw1xx.c | 34 ++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) diff --git a/drivers/net/dsa/lantiq/mxl-gsw1xx.c b/drivers/net/dsa/lantiq/mxl-gsw1xx.c index 4dc287ad141e..f8ff8a604bf5 100644 --- a/drivers/net/dsa/lantiq/mxl-gsw1xx.c +++ b/drivers/net/dsa/lantiq/mxl-gsw1xx.c @@ -11,10 +11,12 @@ #include #include +#include #include #include #include #include +#include #include #include "lantiq_gswip.h" @@ -29,6 +31,7 @@ struct gsw1xx_priv { struct regmap *clk; struct regmap *shell; struct phylink_pcs pcs; + struct delayed_work clear_raneg; phy_interface_t tbi_interface; struct gswip_priv gswip; }; @@ -145,7 +148,9 @@ static void gsw1xx_pcs_disable(struct phylink_pcs *pcs) { struct gsw1xx_priv *priv = pcs_to_gsw1xx(pcs); - /* Assert SGMII shell reset */ + cancel_delayed_work_sync(&priv->clear_raneg); + + /* Assert SGMII shell reset (will also clear RANEG bit) */ regmap_set_bits(priv->shell, GSW1XX_SHELL_RST_REQ, GSW1XX_RST_REQ_SGMII_SHELL); @@ -428,12 +433,29 @@ static int gsw1xx_pcs_config(struct phylink_pcs *pcs, unsigned int neg_mode, return 0; } +static void gsw1xx_pcs_clear_raneg(struct work_struct *work) +{ + struct gsw1xx_priv *priv = + container_of(work, struct gsw1xx_priv, clear_raneg.work); + + regmap_clear_bits(priv->sgmii, GSW1XX_SGMII_TBI_ANEGCTL, + GSW1XX_SGMII_TBI_ANEGCTL_RANEG); +} + static void gsw1xx_pcs_an_restart(struct phylink_pcs *pcs) { struct gsw1xx_priv *priv = pcs_to_gsw1xx(pcs); + cancel_delayed_work_sync(&priv->clear_raneg); + regmap_set_bits(priv->sgmii, GSW1XX_SGMII_TBI_ANEGCTL, GSW1XX_SGMII_TBI_ANEGCTL_RANEG); + + /* despite being documented as self-clearing, the RANEG bit + * sometimes remains set, preventing auto-negotiation from happening. + * MaxLinear advises to manually clear the bit after 10ms. + */ + schedule_delayed_work(&priv->clear_raneg, msecs_to_jiffies(10)); } static void gsw1xx_pcs_link_up(struct phylink_pcs *pcs, @@ -636,6 +658,8 @@ static int gsw1xx_probe(struct mdio_device *mdiodev) if (ret) return ret; + INIT_DELAYED_WORK(&priv->clear_raneg, gsw1xx_pcs_clear_raneg); + ret = gswip_probe_common(&priv->gswip, version); if (ret) return ret; @@ -648,16 +672,21 @@ static int gsw1xx_probe(struct mdio_device *mdiodev) static void gsw1xx_remove(struct mdio_device *mdiodev) { struct gswip_priv *priv = dev_get_drvdata(&mdiodev->dev); + struct gsw1xx_priv *gsw1xx_priv; if (!priv) return; dsa_unregister_switch(priv->ds); + + gsw1xx_priv = container_of(priv, struct gsw1xx_priv, gswip); + cancel_delayed_work_sync(&gsw1xx_priv->clear_raneg); } static void gsw1xx_shutdown(struct mdio_device *mdiodev) { struct gswip_priv *priv = dev_get_drvdata(&mdiodev->dev); + struct gsw1xx_priv *gsw1xx_priv; if (!priv) return; @@ -665,6 +694,9 @@ static void gsw1xx_shutdown(struct mdio_device *mdiodev) dsa_switch_shutdown(priv->ds); dev_set_drvdata(&mdiodev->dev, NULL); + + gsw1xx_priv = container_of(priv, struct gsw1xx_priv, gswip); + cancel_delayed_work_sync(&gsw1xx_priv->clear_raneg); } static const struct gswip_hw_info gsw12x_data = { -- 2.47.3