From 4488f6b6148045424459ef1d5b153c6895ee1dbb Mon Sep 17 00:00:00 2001 From: Divya Koppera Date: Fri, 4 Mar 2022 15:04:16 +0530 Subject: [PATCH] net: phy: micrel: Fix concurrent register access Make Extended page register accessing atomic, to overcome unexpected output from register reads/writes. Fixes: 7c2dcfa295b1 ("net: phy: micrel: Add support for LAN8804 PHY") Signed-off-by: Divya Koppera Signed-off-by: David S. Miller --- drivers/net/phy/micrel.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c index a7ebcda..281cebc 100644 --- a/drivers/net/phy/micrel.c +++ b/drivers/net/phy/micrel.c @@ -1596,11 +1596,13 @@ static int lanphy_read_page_reg(struct phy_device *phydev, int page, u32 addr) { u32 data; - phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, page); - phy_write(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA, addr); - phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, - (page | LAN_EXT_PAGE_ACCESS_CTRL_EP_FUNC)); - data = phy_read(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA); + phy_lock_mdio_bus(phydev); + __phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, page); + __phy_write(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA, addr); + __phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, + (page | LAN_EXT_PAGE_ACCESS_CTRL_EP_FUNC)); + data = __phy_read(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA); + phy_unlock_mdio_bus(phydev); return data; } @@ -1608,18 +1610,18 @@ static int lanphy_read_page_reg(struct phy_device *phydev, int page, u32 addr) static int lanphy_write_page_reg(struct phy_device *phydev, int page, u16 addr, u16 val) { - phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, page); - phy_write(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA, addr); - phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, - (page | LAN_EXT_PAGE_ACCESS_CTRL_EP_FUNC)); + phy_lock_mdio_bus(phydev); + __phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, page); + __phy_write(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA, addr); + __phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, + page | LAN_EXT_PAGE_ACCESS_CTRL_EP_FUNC); - val = phy_write(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA, val); - if (val) { + val = __phy_write(phydev, LAN_EXT_PAGE_ACCESS_ADDRESS_DATA, val); + if (val != 0) phydev_err(phydev, "Error: phy_write has returned error %d\n", val); - return val; - } - return 0; + phy_unlock_mdio_bus(phydev); + return val; } static int lan8814_config_init(struct phy_device *phydev) -- 2.7.4