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Groups > linux.kernel > #1399832
| From | Roger Quadros <rogerq@ti.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH v7 10/14] usb: otg: add hcd companion support |
| Date | 2016-05-12 11:40 +0200 |
| Message-ID | <rxVg7-2MC-15@gated-at.bofh.it> (permalink) |
| References | <rxD9w-1n1-21@gated-at.bofh.it> <rxDCy-1G3-9@gated-at.bofh.it> <rxQ6J-68P-1@gated-at.bofh.it> <rxUk2-1QS-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
Hi, On 12/05/16 11:34, Roger Quadros wrote: > On 12/05/16 07:00, Yoshihiro Shimoda wrote: >> Hi, >> >>> From: Alan Stern >>> Sent: Wednesday, May 11, 2016 11:47 PM >>> >>> On Wed, 11 May 2016, Roger Quadros wrote: >>> >>>>> What I mean is if you have 2 EHCI controllers with 2 companion >>>>> controllers, don't you need to know which companion goes with which EHCI >>>>> controller? Just like you do for the otg-controller property. >>>>> >>>> >>>> That is a very good point. I'm not very sure and it seems that current code won't work >>>> with multiple EHCI + companion instances. >> >> I may misunderstand this topic, but if I use the following environment, it works correctly. >> >> < My environment > >> - an otg controller: Sets hcd-needs-companion. >> - ehci0 and ohci0 and a function: They connect to the otg controller using "otg-controller" property. >> - ehci1 and ohci1: No "otg-controller" property. >> - ehci2 and ohci2: No "otg-controller" property. >> >> In this environment, all hosts works correctly. >> Also I think if we have 2 otg controlelrs, it should be work because otg_dev instance differs. > > The topic is about more than one otg controllers and how to tie the right ehci and ohci > to the correct otg_dev instance especially in cases where we can't depend on probe order. > >> Or, does this topic assume an otg controller handles 2 EHCI controllers? >> I'm not sure such environment actually exists. > > No it is not about that. > >> >>>> Alan, does USB core even know which EHCI and OHCI are linked to the same port >>>> or the handoff is software transparent? >>> >>> The core knows. It doesn't use the information for a whole lot of >>> things, but it does use it in a couple of places. Search for >>> "companion" in core/hcd-pci.c and you'll see. >> >> Thank you for the information. I didn't know this code. >> If my understanding is correct, the core/hcd-pci.c code will not be used by non-PCI devices. > > That is correct. > >> In other words, nobody sets "hcd->self.hs_companion" if we use such a device. >> So, I will try to add such a code if needed. > > I think OTG core would have to rely on USB core in providing the right companion device, > just like we rely on it for the primary vs shared HCD case. > OK, it is not so simple. EHCI and companion port handoff is really meant to be software transparent. non-PCI devices really don't have knowledge of which OHCI instance is companion to the EHCI. With device tree we could provide this mapping but for non-device tree case we can't do anything. So my suggestion would be to keep dual role implementation limited to one instance for EHCI + companion case for non-DT. For PCI case I don't see how dual role can be implemented. I don't think we have any dual-role PCI cards. For DT case we could have a DT binding to tie the EHCI and companion and use that in the OTG framework. Any objections? cheers, -roger
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[PATCH v7 00/14] USB OTG/dual-role framework Roger Quadros <rogerq@ti.com> - 2016-05-02 14:20 +0200
[PATCH v7 02/14] usb: otg-fsm: Prevent build warning "VDBG" redefined Roger Quadros <rogerq@ti.com> - 2016-05-02 14:20 +0200
Re: [PATCH v7 02/14] usb: otg-fsm: Prevent build warning "VDBG" redefined Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 10:30 +0200
[PATCH v7 07/14] usb: otg: get rid of CONFIG_USB_OTG_FSM in favour of CONFIG_USB_OTG Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 07/14] usb: otg: get rid of CONFIG_USB_OTG_FSM in favour of CONFIG_USB_OTG Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 10:40 +0200
[PATCH v7 09/14] usb: of: add an API to get OTG device from USB controller node Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 09/14] usb: of: add an API to get OTG device from USB controller node Rob Herring <robh@kernel.org> - 2016-05-04 15:20 +0200
Re: [PATCH v7 09/14] usb: of: add an API to get OTG device from USB controller node Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 10:50 +0200
Re: [PATCH v7 09/14] usb: of: add an API to get OTG device from USB controller node Roger Quadros <rogerq@ti.com> - 2016-05-11 13:10 +0200
[PATCH v7 11/14] usb: otg: use dev_dbg() instead of VDBG() Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 11/14] usb: otg: use dev_dbg() instead of VDBG() Peter Chen <hzpeterchen@gmail.com> - 2016-05-06 11:20 +0200
Re: [PATCH v7 11/14] usb: otg: use dev_dbg() instead of VDBG() Roger Quadros <rogerq@ti.com> - 2016-05-09 11:50 +0200
Re: [PATCH v7 11/14] usb: otg: use dev_dbg() instead of VDBG() Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 11:00 +0200
[PATCH v7 14/14] usb: host: xhci-plat: Add otg device to platform data Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 14/14] usb: host: xhci-plat: Add otg device to platform data Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 11:10 +0200
[PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Peter Chen <hzpeterchen@gmail.com> - 2016-05-06 11:50 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Roger Quadros <rogerq@ti.com> - 2016-05-09 11:50 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Peter Chen <hzpeterchen@gmail.com> - 2016-05-10 05:30 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Roger Quadros <rogerq@ti.com> - 2016-05-10 09:40 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Felipe Balbi <balbi@kernel.org> - 2016-05-10 10:20 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Roger Quadros <rogerq@ti.com> - 2016-05-10 11:20 +0200
RE: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Jun Li <jun.li@nxp.com> - 2016-05-10 10:20 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Roger Quadros <rogerq@ti.com> - 2016-05-10 11:30 +0200
Re: [PATCH v7 03/14] usb: hcd.h: Add OTG to HCD interface Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 08:30 +0200
[PATCH v7 12/14] usb: hcd: Adapt to OTG core Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 12/14] usb: hcd: Adapt to OTG core Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 11:10 +0200
[PATCH v7 01/14] usb: hcd: Initialize hcd->flags to 0 Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 01/14] usb: hcd: Initialize hcd->flags to 0 Peter Chen <hzpeterchen@gmail.com> - 2016-05-06 11:20 +0200
[PATCH v7 06/14] usb: gadget.h: Add OTG to gadget interface Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
[PATCH v7 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 08/14] usb: otg: add OTG/dual-role core Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 10:50 +0200
Re: [PATCH v7 08/14] usb: otg: add OTG/dual-role core Roger Quadros <rogerq@ti.com> - 2016-05-11 13:10 +0200
[PATCH v7 13/14] usb: gadget: udc: adapt to OTG core Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
[PATCH v7 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 08:20 +0200
Re: [PATCH v7 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Roger Quadros <rogerq@ti.com> - 2016-05-11 13:10 +0200
Re: [PATCH v7 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Roger Quadros <rogerq@ti.com> - 2016-05-11 14:40 +0200
Re: [PATCH v7 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Peter Chen <hzpeterchen@gmail.com> - 2016-05-12 10:30 +0200
Re: [PATCH v7 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Roger Quadros <rogerq@ti.com> - 2016-05-12 10:40 +0200
[PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-02 14:30 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Rob Herring <robh@kernel.org> - 2016-05-04 15:20 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-04 15:50 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Rob Herring <robh@kernel.org> - 2016-05-11 16:00 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-11 16:20 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Alan Stern <stern@rowland.harvard.edu> - 2016-05-11 16:50 +0200
RE: [PATCH v7 10/14] usb: otg: add hcd companion support Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> - 2016-05-12 06:10 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-12 10:40 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-12 11:40 +0200
RE: [PATCH v7 10/14] usb: otg: add hcd companion support Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> - 2016-05-12 12:40 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-12 14:20 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Peter Chen <hzpeterchen@gmail.com> - 2016-05-16 04:30 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-16 10:10 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Peter Chen <hzpeterchen@gmail.com> - 2016-05-16 10:30 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Roger Quadros <rogerq@ti.com> - 2016-05-16 10:40 +0200
RE: [PATCH v7 10/14] usb: otg: add hcd companion support Alan Stern <stern@rowland.harvard.edu> - 2016-05-12 20:20 +0200
Re: [PATCH v7 10/14] usb: otg: add hcd companion support Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 11:00 +0200
Re: [PATCH v7 00/14] USB OTG/dual-role framework Peter Chen <hzpeterchen@gmail.com> - 2016-05-11 10:50 +0200
Re: [PATCH v7 00/14] USB OTG/dual-role framework Roger Quadros <rogerq@ti.com> - 2016-05-11 13:10 +0200
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