Re: [PATCH v3 0/6] usb: host: change TPL support behaviour

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, Sep 04, 2014 at 07:49:23AM +0800, Peter Chen wrote:
> On Wed, Sep 03, 2014 at 02:02:04PM -0400, Alan Stern wrote:
> > On Wed, 3 Sep 2014, Peter Chen wrote:
> > 
> > > On Fri, Aug 22, 2014 at 02:31:18PM +0530, Pratyush Anand wrote:
> > > > On Tue, Aug 19, 2014 at 09:51:51AM +0800, Peter Chen wrote:
> > > > > Changes for v3:
> > > > > - Add possible role switch for unsupported HNP capable OTG B-peripheral,
> > > > > see USB OTG & EH 2.0 spec page 38, this feature was deleted wrongly
> > > > > at previous revision patches.
> > > > > 
> > > > > Changes for v2:
> > > > > - Move TPL support judgement out of is_target, the user can be easy to
> > > > > know if it needs to do TPL judgement. [patch 1/6]
> > > > > - Keep the unsupport device message unchange [patch 1/6]
> > > > > 
> > > > > According to On-The-Go and Embedded Host Supplement to the USB Revision
> > > > > 2.0 Specification, a Targeted Host (non-PC host, OTG or Embedded host)
> > > > > is not required to support operation with all types of USB peripherals.
> > > > > It is up to the manufacturer of each Targeted Host to declare which peripherals
> > > > > the host will support and provide a list of those peripherals. This is called
> > > > > the Targeted Host's "Targeted Peripheral List" (TPL). The TPL shall accurately
> > > > > represent the device classes supported by the Targeted Host.
> > > > > 
> > > > > And the TPL support is a must for USB OTG & EH certification test, and TPL
> > > > > support needs to apply for both OTG and EH, it should be decided by platform
> > > > > setting.
> > > > > 
> > > > > This patchset changes TPL support behaviour like below:
> > > > > - Apply possible TPL support for all kinds of host
> > > > > - Effect TPL in code is decided by both configuration
> > > > > (CONFIG_USB_OTG_WHITELIST) and platform flag, it can avoid
> > > > > the enumeration failure by choosing TPL configuration wrongly.
> > > > > 
> > > > > Besides, TPL can be have a good supplement for authorized feature supplied
> > > > > by sys, Eg, TPL can be modified to match by class using interface descriptor, etc.
> > > > > It may help give some suggestions for recently badUSB report.
> > > > > http://venturebeat.com/2014/07/31/why-you-can-no-longer-trust-any-usb-device-plugged-into-your-pc/
> > > > > https://srlabs.de/badusb/
> > 
> > > Hi Greg & Alan, any comments for this patchset?
> > 
> > In patch 2/6, why did you move the !is_targeted(udev) code from 
> > usb_enumerate_device_otg() to usb_enumerate_device()?  Why not leave 
> > the code where it is?
> > 
> 
> TPL support is also needed for embedded host, not only otg host.
> 
> -- 
> Best Regards,
> Peter Chen

-- 
Best Regards,
Peter Chen
--
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




[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux