From 2b3e88ea65287ba738a798622405b15344871085 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Sun, 16 Dec 2018 18:30:14 +0100 Subject: [PATCH] net: phy: improve phy state checking Add helpers phy_is_started() and __phy_is_started() to avoid open-coded checks whether PHY has been started. To make the check easier move PHY_HALTED before PHY_UP in enum phy_state. Further improvements: phy_start_aneg(): Return -EBUSY and print warning if function is called from a non-started state (DOWN, READY, HALTED). Better check because function is exported and drivers may use it incorrectly. phy_interrupt(): Return IRQ_NONE also if state is DOWN or READY. We should never receive an interrupt in one of these states, but better play safe. phy_stop(): Just return and print a warning if PHY is in a non-started state. This warning should help to identify drivers with unbalanced calls to phy_start() / phy_stop(). phy_state_machine(): Schedule state machine run only if PHY is in a started state. E.g. if state is READY we don't need the state machine, it will be started by phy_start(). v2: - don't use __func__ within phy_warn_state v3: - use WARN() instead of printing error message to facilitate debugging Signed-off-by: Heiner Kallweit Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/phy/phy.c | 34 +++++++++++++++++++++------------- include/linux/phy.h | 24 +++++++++++++++++++++++- 2 files changed, 44 insertions(+), 14 deletions(-) diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c index e24708f1fc16..21df28b9882c 100644 --- a/drivers/net/phy/phy.c +++ b/drivers/net/phy/phy.c @@ -543,6 +543,13 @@ int phy_start_aneg(struct phy_device *phydev) mutex_lock(&phydev->lock); + if (!__phy_is_started(phydev)) { + WARN(1, "called from state %s\n", + phy_state_to_str(phydev->state)); + err = -EBUSY; + goto out_unlock; + } + if (AUTONEG_DISABLE == phydev->autoneg) phy_sanitize_settings(phydev); @@ -553,13 +560,11 @@ int phy_start_aneg(struct phy_device *phydev) if (err < 0) goto out_unlock; - if (phydev->state != PHY_HALTED) { - if (AUTONEG_ENABLE == phydev->autoneg) { - err = phy_check_link_status(phydev); - } else { - phydev->state = PHY_FORCING; - phydev->link_timeout = PHY_FORCE_TIMEOUT; - } + if (phydev->autoneg == AUTONEG_ENABLE) { + err = phy_check_link_status(phydev); + } else { + phydev->state = PHY_FORCING; + phydev->link_timeout = PHY_FORCE_TIMEOUT; } out_unlock: @@ -709,7 +714,7 @@ void phy_stop_machine(struct phy_device *phydev) cancel_delayed_work_sync(&phydev->state_queue); mutex_lock(&phydev->lock); - if (phydev->state > PHY_UP && phydev->state != PHY_HALTED) + if (__phy_is_started(phydev)) phydev->state = PHY_UP; mutex_unlock(&phydev->lock); } @@ -760,7 +765,7 @@ static irqreturn_t phy_interrupt(int irq, void *phy_dat) { struct phy_device *phydev = phy_dat; - if (PHY_HALTED == phydev->state) + if (!phy_is_started(phydev)) return IRQ_NONE; /* It can't be ours. */ if (phydev->drv->did_interrupt && !phydev->drv->did_interrupt(phydev)) @@ -842,15 +847,18 @@ void phy_stop(struct phy_device *phydev) { mutex_lock(&phydev->lock); - if (PHY_HALTED == phydev->state) - goto out_unlock; + if (!__phy_is_started(phydev)) { + WARN(1, "called from state %s\n", + phy_state_to_str(phydev->state)); + mutex_unlock(&phydev->lock); + return; + } if (phy_interrupt_is_valid(phydev)) phy_disable_interrupts(phydev); phydev->state = PHY_HALTED; -out_unlock: mutex_unlock(&phydev->lock); phy_state_machine(&phydev->state_queue.work); @@ -984,7 +992,7 @@ void phy_state_machine(struct work_struct *work) * state machine would be pointless and possibly error prone when * called from phy_disconnect() synchronously. */ - if (phy_polling_mode(phydev) && old_state != PHY_HALTED) + if (phy_polling_mode(phydev) && phy_is_started(phydev)) phy_queue_state_machine(phydev, PHY_STATE_TIME); } diff --git a/include/linux/phy.h b/include/linux/phy.h index 8f927246acdb..da039f211c22 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -319,12 +319,12 @@ struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr); enum phy_state { PHY_DOWN = 0, PHY_READY, + PHY_HALTED, PHY_UP, PHY_RUNNING, PHY_NOLINK, PHY_FORCING, PHY_CHANGELINK, - PHY_HALTED, PHY_RESUMING }; @@ -669,6 +669,28 @@ phy_lookup_setting(int speed, int duplex, const unsigned long *mask, size_t phy_speeds(unsigned int *speeds, size_t size, unsigned long *mask); +static inline bool __phy_is_started(struct phy_device *phydev) +{ + WARN_ON(!mutex_is_locked(&phydev->lock)); + + return phydev->state >= PHY_UP; +} + +/** + * phy_is_started - Convenience function to check whether PHY is started + * @phydev: The phy_device struct + */ +static inline bool phy_is_started(struct phy_device *phydev) +{ + bool started; + + mutex_lock(&phydev->lock); + started = __phy_is_started(phydev); + mutex_unlock(&phydev->lock); + + return started; +} + void phy_resolve_aneg_linkmode(struct phy_device *phydev); /**