On 07/26/2017 12:24 PM, Florian Fainelli wrote:
> Marc reported that he was not getting the PHY library adjust_link()
> callback function to run when calling phy_stop() + phy_disconnect()
> which does not indeed happen because we don't make sure we flush the
> PHYLIB delayed work and let it run to completion. We also need to have
> a synchronous call to phy_state_machine() in order to have the state
> machine actually act on PHY_HALTED, set the PHY device's link down, turn
> the network device's carrier off and finally call the adjust_link()
> function.
>
> Reported-by: Marc Gonzalez <marc_gonza...@sigmadesigns.com>
> Fixes: a390d1f379cf ("phylib: convert state_queue work to delayed_work")
> Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
> ---
> David, this dates back from before the commit mentioned in Fixes but it would
> be hard to backport to earlier kernels if we flagged the original design flaw
> that used timers. Also, I am not clear on the timer API whether there was a
> way
> to ensure timers would run to completion before they would be cancelled.
>
> Marc, please add your Signed-off-by tag since you contributed the second line.
>
> Thanks!
David, please hold off before applying this, I found a corner case with
power management where we may be accessing clock gated registers and
cause bus errors, will report back here.
>
> drivers/net/phy/phy.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index d0626bf5c540..30e7c43e0d87 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -743,12 +743,17 @@ void phy_trigger_machine(struct phy_device *phydev,
> bool sync)
> */
> void phy_stop_machine(struct phy_device *phydev)
> {
> + /* Run the state machine to completion */
> + flush_delayed_work(&phydev->state_queue);
> cancel_delayed_work_sync(&phydev->state_queue);
>
> mutex_lock(&phydev->lock);
> if (phydev->state > PHY_UP && phydev->state != PHY_HALTED)
> phydev->state = PHY_UP;
> mutex_unlock(&phydev->lock);
> +
> + /* Now we can run the state machine synchronously */
> + phy_state_machine(&phydev->state_queue.work);
> }
>
> /**
>
--
Florian
