Re: [PATCH] driver core: Don't try to create links if they are not needed

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, Sep 16, 2024 at 03:50:34PM +0100, Jon Hunter wrote:
> 
> On 11/09/2024 15:32, Greg Kroah-Hartman wrote:
> > On Tue, Sep 10, 2024 at 02:00:19PM +0100, Jon Hunter wrote:
> > > The following error messages are observed on boot with the Tegra234
> > > Jetson AGX Orin board ...
> > > 
> > >   tegra-xusb-padctl 3520000.padctl: Failed to create device link (0x180)
> > >     with 1-0008
> > >   tegra-xusb-padctl 3520000.padctl: Failed to create device link (0x180)
> > >     with 1-0008
> > >   tegra-xusb-padctl 3520000.padctl: Failed to create device link (0x180)
> > >     with 1-0008
> > > 
> > > In the above case, device_link_add() intentionally returns NULL because
> > > these are SYNC_STATE_ONLY links and the device is already probed.
> > > Therefore, the above messages are not actually errors. Fix this by
> > > replicating the test from device_link_add() in the function
> > > fw_devlink_create_devlink() and don't call device_link_add() if there
> > > are no links to create.
> > > 
> > > Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
> > 
> > What commit id does this fix?
> 
> 
> Hard to say exactly. The above error message was first added with commit
> 3fb16866b51d ("driver core: fw_devlink: Make cycle detection more robust")
> but at this time we did not have the support in place for Tegra234 USB. I am
> guessing we first started seeing this when I enabled support for the type-c
> controller in commit 16744314ee57 ("arm64: tegra: Populate USB Type-C
> Controller for Jetson AGX Orin"). I can confirm if that is helpful?
> 

That helps, I'll look at this after -rc1 is out, thanks!

greg k-h