[PATCH net v2 2/2] net: mt7531: ensure all MACs are powered down before reset

Alexander Couzens
2022-09-17T01:00:16Z

The datasheet [1] explicit describes it as requirement for a reset.

[1] MT7531 Reference Manual for Development Board rev 1.0, page 735

Signed-off-by: Alexander Couzens <lynxis@fe80.eu>
---
drivers/net/dsa/mt7530.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 95a57aeb466e..409d5c3d76ea 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -2329,6 +2329,10 @@ mt7531_setup(struct dsa_switch *ds)
return -ENODEV;
}

+ /* all MACs must be forced link-down before sw reset */
+ for (i = 0; i < MT7530_NUM_PORTS; i++)
+ mt7530_write(priv, MT7530_PMCR_P(i), MT7531_FORCE_LNK);
+
/* Reset the switch through internal reset */
mt7530_write(priv, MT7530_SYS_CTRL,
SYS_CTRL_PHY_RST | SYS_CTRL_SW_RST |
--
2.37.3