Subject: Re: "asix: Don't reset PHY on if_up for ASIX 88772" breaks net on arndale platform

From: Riku Voipio <[email-masked]>
Date: Thu, 6 Nov 2014 14:04:16 +0200

On Thu, Nov 06, 2014 at 10:01:04AM +0000, Charles Keepax wrote:
> On Thu, Nov 06, 2014 at 11:06:51AM +0200, Riku Voipio wrote:
> > The asix on arndale comes semi-configured from u-boot, which I guess is
> > not the state kernel expects it to come in. At least in my case where
> > I use tftp from u-boot to load my kernel.
> > 
> > So probably the full reset is needed here to make the asix chip come
> > to a truly pristine state.
> > 
> > The commit that Michel partially reverted (by returning to use
> > ax88772_link_reset instead of ax88772_reset), indicates that a strong reset
> > is needed for suspend/resume as well:
 
> Ok I think I have cracked this one. I am pretty sure you are
> right that the USB comes to us in a strange state and needs
> a full reset, but that only needs to happen once when the driver
> is bound in. So there is some code in ax88772_bind that appears
> to try to reset the device but does a lot less than ax88772_reset
> and I think that must be the problem. Applying the following on
> top of the patch we have been debating I think will make
> everything work for all of us:

The patch below on top of 3.18-rc3 fixes arndale network for me.

Tested-by: Riku Voipio <[email-masked]>

> --- a/drivers/net/usb/asix_devices.c
> +++ b/drivers/net/usb/asix_devices.c
> @@ -465,19 +465,7 @@ static int ax88772_bind(struct usbnet *dev,
> struct usb_interface *in
>                 return ret;
>         }
> 
> -       ret = asix_sw_reset(dev, AX_SWRESET_IPPD | AX_SWRESET_PRL);
> -       if (ret < 0)
> -               return ret;
> -
> -       msleep(150);
> -
> -       ret = asix_sw_reset(dev, AX_SWRESET_CLEAR);
> -       if (ret < 0)
> -               return ret;
> -
> -       msleep(150);
> -
> -       ret = asix_sw_reset(dev, embd_phy ? AX_SWRESET_IPRL : AX_SWRESET_PRTE);
> +       ax88772_reset(dev);
> 
> If you guys could test that and let me know how you get on I will
> send in a proper patch if it looks good.
> 
> Thanks,
> Charles