On 05.01.2021 17:11, Marek Vasut wrote:
> In case the PHY transitions to PHY_HALTED state in phy_stop(), the
> link_change_notify callback is not triggered. That's because the
> phydev->state = PHY_HALTED in phy_stop() is assigned first, and
> phy_state_machine() is called afterward. For phy_state_machine(),
> no state transition happens, because old_state = PHY_HALTED and
> phy_dev->state = PHY_HALTED.
>
> Signed-off-by: Marek Vasut <ma...@denx.de>
> Cc: Andrew Lunn <and...@lunn.ch>
> Cc: David S. Miller <da...@davemloft.net>
> Cc: Heiner Kallweit <hkallwe...@gmail.com>
> ---
> drivers/net/phy/phy.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index 45f75533c47c..fca8c3eebc5d 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -1004,6 +1004,7 @@ EXPORT_SYMBOL(phy_free_interrupt);
> void phy_stop(struct phy_device *phydev)
> {
> struct net_device *dev = phydev->attached_dev;
> + enum phy_state old_state;
>
> if (!phy_is_started(phydev) && phydev->state != PHY_DOWN) {
> WARN(1, "called from state %s\n",
> @@ -1021,8 +1022,17 @@ void phy_stop(struct phy_device *phydev)
> if (phydev->sfp_bus)
> sfp_upstream_stop(phydev->sfp_bus);
>
> + old_state = phydev->state;
> phydev->state = PHY_HALTED;
>
> + if (old_state != phydev->state) {
> + phydev_err(phydev, "PHY state change %s -> %s\n",
> + phy_state_to_str(old_state),
> + phy_state_to_str(phydev->state));
> + if (phydev->drv && phydev->drv->link_change_notify)
> + phydev->drv->link_change_notify(phydev);
> + }
> +
> mutex_unlock(&phydev->lock);
>
> phy_state_machine(&phydev->state_queue.work);
>
Following is RFC as an additional idea. When requesting a new state
from outside the state machine, we could simply provide the old
state to the state machine in a new phy_device member.
Then we shouldn't have to touch phy_stop(), and maybe phy_error().
And it looks cleaner to me than duplicating code from the state
machine to functions like phy_stop().
---
drivers/net/phy/phy.c | 10 +++++++++-
drivers/net/phy/phy_device.c | 1 +
include/linux/phy.h | 3 +++
3 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 45f75533c..347e42d90 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -45,6 +45,7 @@ static const char *phy_state_to_str(enum phy_state st)
{
switch (st) {
PHY_STATE_STR(DOWN)
+ PHY_STATE_STR(INVALID)
PHY_STATE_STR(READY)
PHY_STATE_STR(UP)
PHY_STATE_STR(RUNNING)
@@ -1021,6 +1022,7 @@ void phy_stop(struct phy_device *phydev)
if (phydev->sfp_bus)
sfp_upstream_stop(phydev->sfp_bus);
+ phydev->old_state = phydev->state;
phydev->state = PHY_HALTED;
mutex_unlock(&phydev->lock);
@@ -1086,7 +1088,13 @@ void phy_state_machine(struct work_struct *work)
mutex_lock(&phydev->lock);
- old_state = phydev->state;
+ /* set if a new state is requested from outside the state machine */
+ if (phydev->old_state != PHY_INVALID) {
+ old_state = phydev->old_state;
+ phydev->old_state = PHY_INVALID;
+ } else {
+ old_state = phydev->state;
+ }
switch (phydev->state) {
case PHY_DOWN:
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 80c2e646c..9f8d9f68b 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -620,6 +620,7 @@ struct phy_device *phy_device_create(struct mii_bus *bus,
int addr, u32 phy_id,
device_initialize(&mdiodev->dev);
dev->state = PHY_DOWN;
+ dev->old_state = PHY_INVALID;
mutex_init(&dev->lock);
INIT_DELAYED_WORK(&dev->state_queue, phy_state_machine);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 9effb511a..df48ea88c 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -442,6 +442,7 @@ struct phy_device *mdiobus_scan(struct mii_bus *bus, int
addr);
*/
enum phy_state {
PHY_DOWN = 0,
+ PHY_INVALID,
PHY_READY,
PHY_HALTED,
PHY_UP,
@@ -566,6 +567,8 @@ struct phy_device {
unsigned interrupts:1;
enum phy_state state;
+ /* if a new state is requested from outside the state machine */
+ enum phy_state old_state;
u32 dev_flags;
--
2.30.0
