[PATCH] netdev/fec: fix ifconfig eth0 down hang issue

[Tim Gardner]

On 05/05/2010 10:39 AM, Bryan Wu wrote:
> Folks,
>
> Can I get some ACK for this patch? Tim, I believe this time you will ack it, right?
>
> Thanks,
> -Bryan
>
> On 04/29/2010 03:18 PM, Bryan Wu wrote:
>> BugLink: http://bugs.launchpad.net/bugs/559065
>>
>> In fec open/close function, we need to use phy_connect and phy_disconnect
>> operation before we start/stop phy. Otherwise it will cause system hang.
>>
>> Only call fec_enet_mii_probe() in open function, because the first open
>> action will cause NULL pointer error.
>>
>> Signed-off-by: Bryan Wu<bryan.wu at canonical.com>
>> ---
>>    drivers/net/fec.c |   28 ++++++++++++++++------------
>>    1 files changed, 16 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/net/fec.c b/drivers/net/fec.c
>> index 2280373..692d3c4 100644
>> --- a/drivers/net/fec.c
>> +++ b/drivers/net/fec.c
>> @@ -691,6 +691,8 @@ static int fec_enet_mii_probe(struct net_device *dev)
>>    	struct phy_device *phy_dev = NULL;
>>    	int phy_addr;
>>
>> +	fep->phy_dev = NULL;
>> +
>>    	/* find the first phy */
>>    	for (phy_addr = 0; phy_addr<   PHY_MAX_ADDR; phy_addr++) {
>>    		if (fep->mii_bus->phy_map[phy_addr]) {
>> @@ -721,6 +723,11 @@ static int fec_enet_mii_probe(struct net_device *dev)
>>    	fep->link = 0;
>>    	fep->full_duplex = 0;
>>
>> +	printk(KERN_INFO "%s: Freescale FEC PHY driver [%s] "
>> +		"(mii_bus:phy_addr=%s, irq=%d)\n", dev->name,
>> +		fep->phy_dev->drv->name, dev_name(&fep->phy_dev->dev),
>> +		fep->phy_dev->irq);
>> +
>>    	return 0;
>>    }
>>
>> @@ -768,13 +775,8 @@ static int fec_enet_mii_init(struct platform_device *pdev)
>>    	if (mdiobus_register(fep->mii_bus))
>>    		goto err_out_free_mdio_irq;
>>
>> -	if (fec_enet_mii_probe(dev) != 0)
>> -		goto err_out_unregister_bus;
>> -
>>    	return 0;
>>
>> -err_out_unregister_bus:
>> -	mdiobus_unregister(fep->mii_bus);
>>    err_out_free_mdio_irq:
>>    	kfree(fep->mii_bus->irq);
>>    err_out_free_mdiobus:
>> @@ -928,7 +930,12 @@ fec_enet_open(struct net_device *dev)
>>    	if (ret)
>>    		return ret;
>>
>> -	/* schedule a link state check */
>> +	/* Probe and connect to PHY when open the interface */
>> +	ret = fec_enet_mii_probe(dev);
>> +	if (ret) {
>> +		fec_enet_free_buffers(dev);
>> +		return ret;
>> +	}
>>    	phy_start(fep->phy_dev);
>>    	netif_start_queue(dev);
>>    	fep->opened = 1;
>> @@ -942,10 +949,12 @@ fec_enet_close(struct net_device *dev)
>>
>>    	/* Don't know what to do yet. */
>>    	fep->opened = 0;
>> -	phy_stop(fep->phy_dev);
>>    	netif_stop_queue(dev);
>>    	fec_stop(dev);
>>
>> +	if (fep->phy_dev)
>> +		phy_disconnect(fep->phy_dev);
>> +
>>            fec_enet_free_buffers(dev);
>>    	clk_disable(fep->clk);
>>
>> @@ -1337,11 +1346,6 @@ fec_probe(struct platform_device *pdev)
>>
>>    	clk_disable(fep->clk);
>>
>> -	printk(KERN_INFO "%s: Freescale FEC PHY driver [%s] "
>> -		"(mii_bus:phy_addr=%s, irq=%d)\n", ndev->name,
>> -		fep->phy_dev->drv->name, dev_name(&fep->phy_dev->dev),
>> -		fep->phy_dev->irq);
>> -
>>    	return 0;
>>
>>    failed_register:
>
>

I thought I _did_ ack it once. Just apply the dang thing. It'll either 
work or it won't. There aren't any corner cases with this.

Acked-by: Tim Gardner <tim.gardner at canonical.com>
-- 
Tim Gardner tim.gardner at canonical.com