From 7bdcbbd1d416951d6e27ef63a2701e5370f752ff Mon Sep 17 00:00:00 2001 From: Milos Reljin 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 BugLink: https://bugs.launchpad.net/bugs/2114239 commit bd1bbab717608757cccbbe08b0d46e6c3ed0ced5 upstream. 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 Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/AM8P250MB0124D258E5A71041AF2CC322E1E32@AM8P250MB0124.EURP250.PROD.OUTLOOK.COM Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman Signed-off-by: Noah Wager Signed-off-by: Mehmet Basaran --- 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 3cf614b4cd52..8bb6f370267b 100644 --- a/drivers/net/phy/nxp-c45-tja11xx.c +++ b/drivers/net/phy/nxp-c45-tja11xx.c @@ -1296,6 +1296,8 @@ 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,