From mboxrd@z Thu Jan 1 00:00:00 1970 From: maxime.ripard@free-electrons.com (Maxime Ripard) Date: Mon, 14 Sep 2015 22:25:33 +0200 Subject: [linux-sunxi] [PATCH] musb: sunxi: Ignore VBus errors in host-only mode In-Reply-To: <55F1CE2E.7010409@redhat.com> References: <1438723553-4136-1-git-send-email-hdegoede@redhat.com> <55C31963.2010701@schinagl.nl> <55C3709C.4080609@redhat.com> <55C47041.3000603@schinagl.nl> <55E93D8C.9020804@schinagl.nl> <55F1CA9B.3070204@redhat.com> <20150910183017.GN9885@lukather> <55F1CE2E.7010409@redhat.com> Message-ID: <20150914202533.GF4684@lukather> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Sep 10, 2015 at 08:38:38PM +0200, Hans de Goede wrote: > Hi, > > On 10-09-15 20:30, Maxime Ripard wrote: > >On Thu, Sep 10, 2015 at 08:23:23PM +0200, Hans de Goede wrote: > >>Hi, > >> > >>On 04-09-15 08:43, Olliver Schinagl wrote: > >>>Hey Hans, > >>> > >>>On 07-08-15 10:45, Olliver Schinagl wrote: > >>>> > >>>>>If you change the dr_mode to host then you _must_ also remove any id_det and vbus_det > >>>>>gpio settings from the usb_phy node in the dts, as the sun4i phy code detects > >>>>>host vs otg mode by checking for the presence of these. > >>>>Yes, this fixes it and makes it work. Thanks. > >>>> > >>>I've been going back to this and am wondering if this is something I can look into to fix properly? E.g. if the dts sets dr_mode = host, can we simply ignore the pins and treat them as unset? > >> > >>AFAIK you cannot unset something in dts. The only solution I > >>can comeup with is to add a dr_mode argument to the phy like > >>we already have for the otg controller itself. > >> > >>This is something which we likely need to do anyways to add > >>support for peripheral only mode, which we seem to need for > >>some "hdmi sticks". > > > >I haven't really followed the rest of the discussion, so sorry if you > >already talked about that, but why can't you just set the dr_mode to > >peripheral in such a case? > > This is about the usbphy code not the musb-controller code, which are > 2 different dts nodes, atm only the musb-controller node has a > dr_mode property, and the phy code decides between host-only > and otg mode based on whether an id pin is assigned or not. > > My proposal is to get rid of the id-pin hack to determine the mode > and add a dr_mode property to the usbphy dts node. I agree that we should get rid of that hack, especially since a lack of an ID pin might also be used on a peripheral-only device. However, we already have that information in the musb node, and duplicating the info seems error prone. We already have a custom function, maybe that's a case for another one, and that would allow to handle "hard" cases more easily (like CONFIG_USB_MUSB_HOST selected, with the otg node set to otg). Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: