On Mon, Dec 10, 2012 at 10:18 PM, Steve Glendinning <steve@xxxxxxxxxxx> wrote: > On 10 December 2012 12:09, Oliver Neukum <oliver@xxxxxxxxxx> wrote: >> So this is a problem with remote wakeup on older hardware? > > Exactly, the older hardware revisions can't reliably do it. > >>> Unfortunately we don't know if the connected device supports >>> this feature until we query its ID register at runtime. >>> >>> Suggestions on how best to indicate this capability at runtime >>> instead of compile-time would be appreciated, so we don't have >>> to repeatedly fail if accidentally enabled. Or maybe this is >>> actually the best way? >> >> If this is a problem with remote wakeup, you should up the >> pm counter (usb_autopm_get_noresume()) in .manage_power >> That was the reason I implemented this is a callback and not as >> a helper in usbnet. > > Thanks, so something like this should do the job? This will do, but not simple as clearing .manage_power function pointer in bind(), and still disable runtime suspend for link off case since these devices which don't support suspend 3 can generate remote wakeup for link change event. I suggest to introduce link-off triggered runtime suspend for these usbnet devices(non-LAN9500A device, devices which don't support USB auto-suspend), and I have posted one patch set before[1]. If no one objects that, I'd like to post them again with some fix and update for checking link after link_reset(). [1], http://marc.info/?w=2&r=1&s=usbnet%3A+support+runtime+PM+triggered+by+&q=t > > static int smsc95xx_manage_power(struct usbnet *dev, int on) > { > struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]); > > dev->intf->needs_remote_wakeup = on; > > if (pdata->features & FEATURE_AUTOSUSPEND) > return 0; > > /* this chip revision doesn't support autosuspend */ > netdev_info(dev->net, "hardware doesn't support USB autosuspend\n"); > > if (on) > usb_autopm_get_interface_no_resume(dev->intf); > else > usb_autopm_put_interface_no_suspend(dev->intf); > > return 0; > } Thanks, -- Ming Lei -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
