On Mon, Aug 11, 2014 at 11:25:44AM +0530, Pratyush Anand wrote:
> Hi Peter,
>
> On Thu, Aug 07, 2014 at 02:45:15PM +0800, Peter Chen wrote:
> > According to On-The-Go and Embedded Host Supplement to the USB Revision
> > 2.0 Specification, the targeted hosts (non-PC hosts) include both
> > embedded hosts and otg, and each targeted host product defines the
> > set of supported peripherals on a TPL (Targeted Peripheral List). So,
> > TPL should apply for both OTG and embedded host, and the otg support is
> > not a must for embedded host.
> >
> > The TPL support feature will only be effect when CONFIG_USB_OTG_WHITELIST
> > has been chosen and hcd->tpl_support flag is set, it can avoid the enumeration
> > fails problem for the user who chooses CONFIG_USB_OTG_WHITELIST wrongly.
> >
> > Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
> > ---
> > drivers/usb/core/hub.c | 20 +++-----------------
> > drivers/usb/core/otg_whitelist.h | 22 ++++++++++------------
> > 2 files changed, 13 insertions(+), 29 deletions(-)
> >
> > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> > index 8a4dcbc..5e0b8eb 100644
> > --- a/drivers/usb/core/hub.c
> > +++ b/drivers/usb/core/hub.c
> > @@ -2199,9 +2199,7 @@ static void announce_device(struct usb_device *udev)
> > static inline void announce_device(struct usb_device *udev) { }
> > #endif
> >
> > -#ifdef CONFIG_USB_OTG
> > #include "otg_whitelist.h"
> > -#endif
> >
> > /**
> > * usb_enumerate_device_otg - FIXME (usbcore-internal)
> > @@ -2261,21 +2259,6 @@ static int usb_enumerate_device_otg(struct usb_device *udev)
> > }
> > }
> > }
> > -
> > - if (!is_targeted(udev)) {
> > -
> > - /* Maybe it can talk to us, though we can't talk to it.
> > - * (Includes HNP test device.)
> > - */
> > - if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
> > - err = usb_port_suspend(udev, PMSG_SUSPEND);
> > - if (err < 0)
> > - dev_dbg(&udev->dev, "HNP fail, %d\n", err);
> > - }
> > - err = -ENOTSUPP;
>
> If I did not miss anything then I see an issue if above hunk is removed.
>
> Suppose, there is an OTG B device which is not supported by host, then
> the above hunk was suspending the bus so that B device can get a
> chance to become host. By removing above hunk, how do we cater this
> scenario?
>
> ~Pratyush
>
> PS: All other changes of the series seems fine to me.
>
Pratyush, if it is no problem for my v3 patchset, would you add your ack
or reviewed-by for it? Thanks.
--
Best Regards,
Peter Chen
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