After following the call tree of phy_set_max_speed(), it became clear that this function never returns anything but 0, so we can change its result type to *void* and drop the result checks from the three drivers that actually bothered to do it... Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool. Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxx> Reviewed-by: Andrew Lunn <andrew@xxxxxxx> --- This patch is against the DaveM's 'net-next.git' repo. Changes in version 2: - added Andrew Lunn's tag. drivers/net/ethernet/renesas/ravb_main.c | 8 +------- drivers/net/ethernet/renesas/sh_eth.c | 10 ++-------- drivers/net/phy/aquantia_main.c | 4 +--- drivers/net/phy/phy-core.c | 22 ++++++++-------------- include/linux/phy.h | 2 +- 5 files changed, 13 insertions(+), 33 deletions(-) Index: net-next/drivers/net/ethernet/renesas/ravb_main.c =================================================================== --- net-next.orig/drivers/net/ethernet/renesas/ravb_main.c +++ net-next/drivers/net/ethernet/renesas/ravb_main.c @@ -1432,11 +1432,7 @@ static int ravb_phy_init(struct net_devi * at this time. */ if (soc_device_match(r8a7795es10)) { - err = phy_set_max_speed(phydev, SPEED_100); - if (err) { - netdev_err(ndev, "failed to limit PHY to 100Mbit/s\n"); - goto err_phy_disconnect; - } + phy_set_max_speed(phydev, SPEED_100); netdev_info(ndev, "limited PHY to 100Mbit/s\n"); } @@ -1457,8 +1453,6 @@ static int ravb_phy_init(struct net_devi return 0; -err_phy_disconnect: - phy_disconnect(phydev); err_deregister_fixed_link: if (of_phy_is_fixed_link(np)) of_phy_deregister_fixed_link(np); Index: net-next/drivers/net/ethernet/renesas/sh_eth.c =================================================================== --- net-next.orig/drivers/net/ethernet/renesas/sh_eth.c +++ net-next/drivers/net/ethernet/renesas/sh_eth.c @@ -2026,14 +2026,8 @@ static int sh_eth_phy_init(struct net_de } /* mask with MAC supported features */ - if (mdp->cd->register_type != SH_ETH_REG_GIGABIT) { - int err = phy_set_max_speed(phydev, SPEED_100); - if (err) { - netdev_err(ndev, "failed to limit PHY to 100 Mbit/s\n"); - phy_disconnect(phydev); - return err; - } - } + if (mdp->cd->register_type != SH_ETH_REG_GIGABIT) + phy_set_max_speed(phydev, SPEED_100); phy_attached_info(phydev); Index: net-next/drivers/net/phy/aquantia_main.c =================================================================== --- net-next.orig/drivers/net/phy/aquantia_main.c +++ net-next/drivers/net/phy/aquantia_main.c @@ -533,9 +533,7 @@ static int aqcs109_config_init(struct ph * PMA speed ability bits are the same for all members of the family, * AQCS109 however supports speeds up to 2.5G only. */ - ret = phy_set_max_speed(phydev, SPEED_2500); - if (ret) - return ret; + phy_set_max_speed(phydev, SPEED_2500); return aqr107_set_downshift(phydev, MDIO_AN_VEND_PROV_DOWNSHIFT_DFLT); } Index: net-next/drivers/net/phy/phy-core.c =================================================================== --- net-next.orig/drivers/net/phy/phy-core.c +++ net-next/drivers/net/phy/phy-core.c @@ -243,7 +243,7 @@ size_t phy_speeds(unsigned int *speeds, return count; } -static int __set_linkmode_max_speed(u32 max_speed, unsigned long *addr) +static void __set_linkmode_max_speed(u32 max_speed, unsigned long *addr) { const struct phy_setting *p; int i; @@ -254,13 +254,11 @@ static int __set_linkmode_max_speed(u32 else break; } - - return 0; } -static int __set_phy_supported(struct phy_device *phydev, u32 max_speed) +static void __set_phy_supported(struct phy_device *phydev, u32 max_speed) { - return __set_linkmode_max_speed(max_speed, phydev->supported); + __set_linkmode_max_speed(max_speed, phydev->supported); } /** @@ -273,17 +271,11 @@ static int __set_phy_supported(struct ph * is connected to a 1G PHY. This function allows the MAC to indicate its * maximum speed, and so limit what the PHY will advertise. */ -int phy_set_max_speed(struct phy_device *phydev, u32 max_speed) +void phy_set_max_speed(struct phy_device *phydev, u32 max_speed) { - int err; - - err = __set_phy_supported(phydev, max_speed); - if (err) - return err; + __set_phy_supported(phydev, max_speed); phy_advertise_supported(phydev); - - return 0; } EXPORT_SYMBOL(phy_set_max_speed); @@ -440,7 +432,9 @@ int phy_speed_down_core(struct phy_devic if (min_common_speed == SPEED_UNKNOWN) return -EINVAL; - return __set_linkmode_max_speed(min_common_speed, phydev->advertising); + __set_linkmode_max_speed(min_common_speed, phydev->advertising); + + return 0; } static void mmd_phy_indirect(struct mii_bus *bus, int phy_addr, int devad, Index: net-next/include/linux/phy.h =================================================================== --- net-next.orig/include/linux/phy.h +++ net-next/include/linux/phy.h @@ -1661,7 +1661,7 @@ int phy_disable_interrupts(struct phy_de void phy_request_interrupt(struct phy_device *phydev); void phy_free_interrupt(struct phy_device *phydev); void phy_print_status(struct phy_device *phydev); -int phy_set_max_speed(struct phy_device *phydev, u32 max_speed); +void phy_set_max_speed(struct phy_device *phydev, u32 max_speed); void phy_remove_link_mode(struct phy_device *phydev, u32 link_mode); void phy_advertise_supported(struct phy_device *phydev); void phy_support_sym_pause(struct phy_device *phydev);