Commit a2c054a8 authored by Brad Mouring's avatar Brad Mouring Committed by David S. Miller
Browse files

net: phy: Tell caller result of phy_change() 



In 664fcf12 (net: phy: Threaded interrupts allow some simplification)
the phy_interrupt system was changed to use a traditional threaded
interrupt scheme instead of a workqueue approach.

With this change, the phy status check moved into phy_change, which
did not report back to the caller whether or not the interrupt was
handled. This means that, in the case of a shared phy interrupt,
only the first phydev's interrupt registers are checked (since
phy_interrupt() would always return IRQ_HANDLED). This leads to
interrupt storms when it is a secondary device that's actually the
interrupt source.

Signed-off-by: default avatarBrad Mouring <brad.mouring@ni.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ddc502df

drivers/net/phy/phy.c

+72 −73
Original line number Diff line number Diff line
@@ -617,6 +617,77 @@ static void phy_error(struct phy_device *phydev) 
	phy_trigger_machine(phydev, false);

}



/**

 * phy_disable_interrupts - Disable the PHY interrupts from the PHY side

 * @phydev: target phy_device struct

 */

static int phy_disable_interrupts(struct phy_device *phydev)

{

	int err;



	/* Disable PHY interrupts */

	err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);

	if (err)

		goto phy_err;



	/* Clear the interrupt */

	err = phy_clear_interrupt(phydev);

	if (err)

		goto phy_err;



	return 0;



phy_err:

	phy_error(phydev);



	return err;

}



/**

 * phy_change - Called by the phy_interrupt to handle PHY changes

 * @phydev: phy_device struct that interrupted

 */

static irqreturn_t phy_change(struct phy_device *phydev)

{

	if (phy_interrupt_is_valid(phydev)) {

		if (phydev->drv->did_interrupt &&

		    !phydev->drv->did_interrupt(phydev))

			return IRQ_NONE;



		if (phydev->state == PHY_HALTED)

			if (phy_disable_interrupts(phydev))

				goto phy_err;

	}



	mutex_lock(&phydev->lock);

	if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))

		phydev->state = PHY_CHANGELINK;

	mutex_unlock(&phydev->lock);



	/* reschedule state queue work to run as soon as possible */

	phy_trigger_machine(phydev, true);



	if (phy_interrupt_is_valid(phydev) && phy_clear_interrupt(phydev))

		goto phy_err;

	return IRQ_HANDLED;



phy_err:

	phy_error(phydev);

	return IRQ_NONE;

}



/**

 * phy_change_work - Scheduled by the phy_mac_interrupt to handle PHY changes

 * @work: work_struct that describes the work to be done

 */

void phy_change_work(struct work_struct *work)

{

	struct phy_device *phydev =

		container_of(work, struct phy_device, phy_queue);



	phy_change(phydev);

}



/**

 * phy_interrupt - PHY interrupt handler

 * @irq: interrupt line
@@ -632,9 +703,7 @@ static irqreturn_t phy_interrupt(int irq, void *phy_dat) 
	if (PHY_HALTED == phydev->state)

		return IRQ_NONE;		/* It can't be ours.  */



	phy_change(phydev);



	return IRQ_HANDLED;

	return phy_change(phydev);

}



/**
@@ -651,32 +720,6 @@ static int phy_enable_interrupts(struct phy_device *phydev) 
	return phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);

}



/**

 * phy_disable_interrupts - Disable the PHY interrupts from the PHY side

 * @phydev: target phy_device struct

 */

static int phy_disable_interrupts(struct phy_device *phydev)

{

	int err;



	/* Disable PHY interrupts */

	err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);

	if (err)

		goto phy_err;



	/* Clear the interrupt */

	err = phy_clear_interrupt(phydev);

	if (err)

		goto phy_err;



	return 0;



phy_err:

	phy_error(phydev);



	return err;

}



/**

 * phy_start_interrupts - request and enable interrupts for a PHY device

 * @phydev: target phy_device struct
@@ -719,50 +762,6 @@ int phy_stop_interrupts(struct phy_device *phydev) 
}

EXPORT_SYMBOL(phy_stop_interrupts);



/**

 * phy_change - Called by the phy_interrupt to handle PHY changes

 * @phydev: phy_device struct that interrupted

 */

void phy_change(struct phy_device *phydev)

{

	if (phy_interrupt_is_valid(phydev)) {

		if (phydev->drv->did_interrupt &&

		    !phydev->drv->did_interrupt(phydev))

			return;



		if (phydev->state == PHY_HALTED)

			if (phy_disable_interrupts(phydev))

				goto phy_err;

	}



	mutex_lock(&phydev->lock);

	if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))

		phydev->state = PHY_CHANGELINK;

	mutex_unlock(&phydev->lock);



	/* reschedule state queue work to run as soon as possible */

	phy_trigger_machine(phydev, true);



	if (phy_interrupt_is_valid(phydev) && phy_clear_interrupt(phydev))

		goto phy_err;

	return;



phy_err:

	phy_error(phydev);

}



/**

 * phy_change_work - Scheduled by the phy_mac_interrupt to handle PHY changes

 * @work: work_struct that describes the work to be done

 */

void phy_change_work(struct work_struct *work)

{

	struct phy_device *phydev =

		container_of(work, struct phy_device, phy_queue);



	phy_change(phydev);

}



/**

 * phy_stop - Bring down the PHY link, and stop checking the status

 * @phydev: target phy_device struct

include/linux/phy.h

+0 −1
Original line number Diff line number Diff line
@@ -1012,7 +1012,6 @@ int phy_driver_register(struct phy_driver *new_driver, struct module *owner); 
int phy_drivers_register(struct phy_driver *new_driver, int n,

			 struct module *owner);

void phy_state_machine(struct work_struct *work);

void phy_change(struct phy_device *phydev);

void phy_change_work(struct work_struct *work);

void phy_mac_interrupt(struct phy_device *phydev);

void phy_start_machine(struct phy_device *phydev);

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