[RFC PATCH net-next v5 17/25] net: dsa: qca8k: clear MASTER_EN after phy read/write
From: Ansuel Smith <ansuelsmth@gmail.com>
Date: 2021-05-11 02:09:43
Also in:
lkml, netdev
Subsystem:
networking drivers, networking [dsa], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Andrew Lunn, Vladimir Oltean, Linus Torvalds
Clear MDIO_MASTER_EN bit from MDIO_MASTER_CTRL after read/write operation. The MDIO_MASTER_EN bit is not reset after read/write operation and the next operation can be wrongly interpreted by the switch as a mdio operation. This cause a production of wrong/garbage data from the switch and underfined bheavior. (random port drop, unplugged port flagged with link up, wrong port speed) Also on driver remove the MASTER_CTRL can be left set and cause the malfunction of any next driver using the mdio device. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> --- drivers/net/dsa/qca8k.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index ff46d253e345..6f713289703b 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c@@ -649,8 +649,14 @@ qca8k_mdio_write(struct qca8k_priv *priv, int port, u32 regnum, u16 data) if (ret) return ret; - return qca8k_busy_wait(priv, QCA8K_MDIO_MASTER_CTRL, - QCA8K_MDIO_MASTER_BUSY); + ret = qca8k_busy_wait(priv, QCA8K_MDIO_MASTER_CTRL, + QCA8K_MDIO_MASTER_BUSY); + + /* even if the busy_wait timeouts try to clear the MASTER_EN */ + qca8k_reg_clear(priv, QCA8K_MDIO_MASTER_CTRL, + QCA8K_MDIO_MASTER_EN); + + return ret; } static int
@@ -685,6 +691,10 @@ qca8k_mdio_read(struct qca8k_priv *priv, int port, u32 regnum) val &= QCA8K_MDIO_MASTER_DATA_MASK; + /* even if the busy_wait timeouts try to clear the MASTER_EN */ + qca8k_reg_clear(priv, QCA8K_MDIO_MASTER_CTRL, + QCA8K_MDIO_MASTER_EN); + return val; }
--
2.30.2