> -----Original Message----- > From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> > Sent: Thursday, September 3, 2020 5:39 PM > To: Jun Li <jun.li@xxxxxxx>; mathias.nyman@xxxxxxxxx > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; dl-linux-imx > <linux-imx@xxxxxxx> > Subject: Re: [PATCH v2] usb: xhci: add debugfs support for ep with stream > > On 3.9.2020 10.46, Jun Li wrote: > > > >> -----Original Message----- > >> From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> > >> Sent: Thursday, September 3, 2020 3:24 PM > >> To: Jun Li <jun.li@xxxxxxx>; mathias.nyman@xxxxxxxxx > >> Cc: gregkh@xxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; > >> dl-linux-imx <linux-imx@xxxxxxx> > >> Subject: Re: [PATCH v2] usb: xhci: add debugfs support for ep with > >> stream > >> > >>>> I think this debugfs code is just called too early. It shouldn't > >>>> need to check new_ring pointer at all. > >>>> > >>>> I wrote a fix that changes the order and makes sure endpoint is > >>>> enabled and ring pointer is set correctly before we call > >>>> xhci_debugfs_create_endpoint() > >>>> > >>>> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fg > >>>> it > >>>> .kernel.o > >>>> rg%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Fmnyman%2Fxhci.git%2Fcommit% > >>>> 2F > >>>> %3Fh%3Dfo > >>>> r-usb-linus%26id%3Dcf99aef5624a592fd4f3374c7060bfa1a65f15df&dat > >>>> a= > >>>> 02%7C01%7 > >>>> Cjun.li%40nxp.com%7C73e4663a6f6641fbb8b308d84f3d021a%7C686ea1d3bc2b > >>>> 4c > >>>> 6fa92cd99 > >>>> c5c301635%7C0%7C0%7C637346470803922895&sdata=i4DfCW8EVUSAWnzb8Q > >>>> l4 > >>>> jPjAOD5wp > >>>> tfbaMrO8vKvtDc%3D&reserved=0 > >>> > >>> This is a good place for non-zero Eps, but does not cover ep0. > >>> > >> > >> ep0 is special, it's not touched in these add/drop endpoint or check > >> bandwidth functions. > >> > >> ep0 ring is allocated earlier during slot creation in > >> xhci_alloc_virt_device() > >> ... > >> /* Allocate endpoint 0 ring */ > >> dev->eps[0].ring = xhci_ring_alloc(xhci, 2, 1, TYPE_CTRL, 0, > >> flags); > >> > >> and for debugfs ep00 is added manually together with the slot > >> xhci_debugfs_create_slot() > >> ... > >> xhci_debugfs_create_ring_dir(xhci, &dev->eps[0].ring, "ep00", > >> priv->root); > >> > >> So regarding ep0 the change should be ok. > > > > Sorry, I forgot debugfs of ep0 is created via xhci_debugfs_create_slot(). > > > > Then I think your change is OK, also I gave a test with my stream/UAS > > device on top of your patch and it can work fine. > > > > Do you need I post a new version of my patch(to remove touch of .new_ring)? > > If you could yes, and also change to a double pointer: > > struct xhci_ep_priv { > ... > + struct xhci_ring **show_ring; With current: struct xhci_ring *show_ring; As I use one trb file to show different trb rings for one EP, so I need get the addr of trb ring pointed by show_ring(which can be updated). If I change it to be **show_ring, then I am passing the addr of dev->eps[i].ring to debugfs so I can't use show_ring's update value when show trb, makes me not easy to get the addr of target trb ring. Thanks Li Jun > }; > > And modify other places this change affects, such as: > epriv->show_ring = &dev->eps[ep_index].ring; > > -Mathias
