linux-kernel - Re: [PATCH 2/2] usb: dwc: host: add xhci_plat_priv quirk XHCI_SKIP_PHY

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20220216085831.GA15957@hu-pkondeti-hyd.qualcomm.com>
Date:   Wed, 16 Feb 2022 14:28:31 +0530
From:   Pavan Kondeti <quic_pkondeti@...cinc.com>
To:     Jun Li <lijun.kernel@...il.com>
CC:     Pavan Kondeti <quic_pkondeti@...cinc.com>, Li Jun <jun.li@....com>,
        Sandeep Maheswaram <quic_c_sanm@...cinc.com>,
        Peter Chen <peter.chen@...nel.org>,
        Pawel Laszczak <pawell@...ence.com>,
        Roger Quadros <rogerq@...nel.org>,
        Aswath Govindraju <a-govindraju@...com>,
        "Greg Kroah-Hartman" <gregkh@...uxfoundation.org>,
        Felipe Balbi <balbi@...nel.org>,
        Mathias Nyman <mathias.nyman@...el.com>,
        Stephen Boyd <swboyd@...omium.org>,
        Doug Anderson <dianders@...omium.org>,
        Matthias Kaehlcke <mka@...omium.org>,
        <linux-arm-msm@...r.kernel.org>,
        Linux USB List <linux-usb@...r.kernel.org>,
        lkml <linux-kernel@...r.kernel.org>, <quic_ppratap@...cinc.com>
Subject: Re: [PATCH 2/2] usb: dwc: host: add xhci_plat_priv quirk
 XHCI_SKIP_PHY_INIT

On Wed, Feb 16, 2022 at 04:49:32PM +0800, Jun Li wrote:
> Pavan Kondeti <quic_pkondeti@...cinc.com> 于2022年2月16日周三 16:00写道：
> >
> > On Wed, Feb 16, 2022 at 03:16:40PM +0800, Jun Li wrote:
> > > Sandeep Maheswaram <quic_c_sanm@...cinc.com> 于2022年2月16日周三 14:58写道：
> > > >
> > > > dwc3 manages PHY by own DRD driver, so skip the management by
> > > > HCD core.
> > > > During runtime suspend phy was not getting suspend because
> > > > runtime_usage value is 2.
> > > >
> > > > Signed-off-by: Sandeep Maheswaram <quic_c_sanm@...cinc.com>
> > > > ---
> > > >  drivers/usb/dwc3/host.c | 15 +++++++++++++++
> > > >  1 file changed, 15 insertions(+)
> > > >
> > > > diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
> > > > index eda8719..4a035a8 100644
> > > > --- a/drivers/usb/dwc3/host.c
> > > > +++ b/drivers/usb/dwc3/host.c
> > > > @@ -13,6 +13,14 @@
> > > >  #include <linux/platform_device.h>
> > > >
> > > >  #include "core.h"
> > > > +#include <linux/usb/hcd.h>
> > > > +#include <linux/usb/xhci-plat.h>
> > > > +#include <linux/usb/xhci-quirks.h>
> > > > +
> > > > +
> > > > +static const struct xhci_plat_priv xhci_plat_dwc3_xhci = {
> > > > +       .quirks = XHCI_SKIP_PHY_INIT,
> > > > +};
> > >
> > > It's better to create this xhci_plat_priv by each dwc3 glue layer,
> > > with that, we can use this priv to pass other flags and possibly
> > > override APIs by each glue driver which may not apply to all dwc3
> > > platforms.
> > >
> >
> > Do you see a need for any glue driver to know about this xHC platform data?
> 
> Yes. I have some xhci quirks which are specifix to NXP iMX platforms.
> 
> > AFAICT, glue driver has no direction connection with the dwc3 core. All
> > the required data is coming from dT on ARM based boards. Adding a private
> > interface between dwc3 core and glue for passing xhci platform data seems
> > to be overkill. If there is a pressing need, why not?
> 
> And looking at xhci_plat_priv members
> 
> -struct xhci_plat_priv {
> -       const char *firmware_name;
> -       unsigned long long quirks;
> -       int (*plat_setup)(struct usb_hcd *);
> -       void (*plat_start)(struct usb_hcd *);
> -       int (*init_quirk)(struct usb_hcd *);
> -       int (*suspend_quirk)(struct usb_hcd *);
> -       int (*resume_quirk)(struct usb_hcd *);
> -};
> 
> Are we going to share the same all those quirks and APIs
> implementation across all dwc3 platforms?
> 
Currently Yes. Thats why I am asking if there is a pressing need to
make this more complex than it needs to be..

Thanks,
Pavan