From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH v2 05/22] doc: dt-binding: usb: add otg related properties Date: Mon, 8 Jun 2015 11:06:49 -0500 Message-ID: References: <1433775737-9816-1-git-send-email-jun.li@freescale.com> <1433775737-9816-6-git-send-email-jun.li@freescale.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <1433775737-9816-6-git-send-email-jun.li-KZfg59tc24xl57MIdRCFDg@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Li Jun Cc: Greg Kroah-Hartman , Felipe Balbi , Peter Chen , Linux USB List , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Rob Herring , Pawel Moll , Mark Rutland , macpaul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Roger Quadros List-Id: devicetree@vger.kernel.org On Mon, Jun 8, 2015 at 10:02 AM, Li Jun wrote: > Add otg version, srp, hnp and adp support for usb OTG port, then those OTG > features don't have to be decided by usb gadget drivers. > > Signed-off-by: Li Jun > --- > Documentation/devicetree/bindings/usb/generic.txt | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt > index 477d5bb..7386f4a 100644 > --- a/Documentation/devicetree/bindings/usb/generic.txt > +++ b/Documentation/devicetree/bindings/usb/generic.txt > @@ -11,6 +11,12 @@ Optional properties: > "peripheral" and "otg". In case this attribute isn't > passed via DT, USB DRD controllers should default to > OTG. > + - otg-rev: tells usb driver the release number of the OTG and EH supplement > + with which the device and its descriptors are compliant, > + in binary-coded decimal (i.e. 2.0 is 0200H). I would assume OTG 2.0 is somehow backwards compatible? Is this a h/w dependency or a driver feature? > + - srp-support: tells OTG controllers we want to enable SRP. > + - hnp-support: tells OTG controllers we want to enable HNP. > + - adp-support: tells OTG controllers we want to enable ADP. I've recently run into a problem[1] and found that I have to disable OTG in the kernel to get my device to work. Having to turn-off OTG seems like the wrong solution, and shifting the problem to DT seems wrong too. Why is this not a user configurable option (within whatever h/w constraints there are)? What are the valid combinations? When do we want these enabled or not? Wouldn't default enabled be better? We already have dr_mode property. How is it related to these? Rob [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1047527 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html