Re: [PATCH 2/2] netdev/fec: fix ifconfig eth0 down hang issue

[Bryan Wu <bryan.wu@canonical.com>]

Since this patch is for another bug and doesn't depend on my first one patch.
Could you please review this?

Thanks,
-Bryan

On 05/07/2010 10:27 AM, 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@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 9c58f6b..af4243f 100644
> --- a/drivers/net/fec.c
> +++ b/drivers/net/fec.c
> @@ -678,6 +678,8 @@ 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]) {
> @@ -708,6 +710,11 @@ 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;
>  }
>  
> @@ -753,13 +760,8 @@ 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:
> @@ -912,7 +914,12 @@ 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;
> @@ -926,10 +933,12 @@ 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);
>  
>  	return 0;
> @@ -1293,11 +1302,6 @@ fec_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto failed_register;
>  
> -	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: