From bd1bbab717608757cccbbe08b0d46e6c3ed0ced5 Mon Sep 17 00:00:00 2001
From: Milos Reljin <milos_reljin@outlook.com>
Date: Fri, 24 Jan 2025 10:41:02 +0000
Subject: [PATCH] net: phy: c45-tjaxx: add delay between MDIO write and read in
soft_reset
In application note (AN13663) for TJA1120, on page 30, there's a figure
with average PHY startup timing values following software reset.
The time it takes for SMI to become operational after software reset
ranges roughly from 500 us to 1500 us.
This commit adds 2000 us delay after MDIO write which triggers software
reset. Without this delay, soft_reset function returns an error and
prevents successful PHY init.
Cc: stable@vger.kernel.org
Fixes: b050f2f15e04 ("phy: nxp-c45: add driver for tja1103")
Signed-off-by: Milos Reljin <milos_reljin@outlook.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/AM8P250MB0124D258E5A71041AF2CC322E1E32@AM8P250MB0124.EURP250.PROD.OUTLOOK.COM
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
drivers/net/phy/nxp-c45-tja11xx.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/net/phy/nxp-c45-tja11xx.c b/drivers/net/phy/nxp-c45-tja11xx.c
index 323717a4821fc..34231b5b91754 100644
--- a/drivers/net/phy/nxp-c45-tja11xx.c
+++ b/drivers/net/phy/nxp-c45-tja11xx.c
@@ -1297,6 +1297,8 @@ static int nxp_c45_soft_reset(struct phy_device *phydev)
if (ret)
return ret;
+ usleep_range(2000, 2050);
+
return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_VEND1,
VEND1_DEVICE_CONTROL, ret,
!(ret & DEVICE_CONTROL_RESET), 20000,
--
GitLab