Re: [PATCH v6 07/12] usb: otg: add OTG/dual-role core

[Peter Chen <hzpeterchen@gmail.com>]

On Wed, Apr 20, 2016 at 10:03:34AM +0300, Roger Quadros wrote:
> On 20/04/16 08:08, Yoshihiro Shimoda wrote:
> > Hi,
> > 
> >> From: Peter Chen
> >> Sent: Tuesday, April 19, 2016 6:18 PM
> >>
> >> On Fri, Apr 15, 2016 at 10:03:16AM +0000, Yoshihiro Shimoda wrote:
> >>> Hi,
> >>>
> >>>> From: Yoshihiro Shimoda
> >>>> Sent: Friday, April 15, 2016 6:59 PM
> >>>>
> >>>> Hi,
> >>>>
> >>>>> From: Roger Quadros
> >>>>> Sent: Thursday, April 14, 2016 8:32 PM
> >>>>>
> >>>>> On 14/04/16 14:15, Yoshihiro Shimoda wrote:
> >>>>>> Hi,
> >>>>>>
> >>>> < snip >
> >>>>>>>> @@ -865,7 +867,8 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum,
> >>>>>>>>  	 * we're ready only if we have shared HCD
> >>>>>>>>  	 * or we don't need shared HCD.
> >>>>>>>>  	 */
> >>>>>>>> -	if (otg->shared_hcd.hcd || !otg->primary_hcd.hcd->shared_hcd) {
> >>>>>>>> +	if (otg->shared_hcd.hcd || (!otg->caps->needs_companion &&
> >>>>>>>> +				    !otg->primary_hcd.hcd->shared_hcd)) {
> >>>>>>>>  		otg->host = hcd_to_bus(hcd);
> >>>>>>>>  		/* FIXME: set bus->otg_port if this is true OTG port with HNP */
> >>>>>>>>
> >>>>>>>
> >>>>>>> These changes look good to me. Thanks.
> >>>>>>
> >>>>>> Thank you for the comment.
> >>>>>> If we change the "needs_companion" place to the otg_config,
> >>>>>> do we need to add a flag into the otg, instead of otg->caps?
> >>>>>
> >>>>> Yes we can add a flag in struct usb_otg.
> >>>>
> >>>> Thank you for the comment.
> >>>>
> >>>> I made a fixed patch.
> >>>> So, should I send this patch to ML after you sent v7 patches?
> >>>> Or, would you apply this patch before you send v7 patches?
> >>>
> >>> Oops, I sent this email without my patch...
> >>>
> >>> ---
> >>> Subject: [PATCH] usb: otg: add hcd companion support
> >>>
> >>> Since some host controller (e.g. EHCI) needs a companion host controller
> >>> (e.g. OHCI), this patch adds such a configuration to use it in the OTG
> >>> core.
> >>>
> >>> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> >>> ---
> >>>  Documentation/devicetree/bindings/usb/generic.txt |  3 +++
> >>>  drivers/usb/common/usb-otg.c                      | 17 +++++++++++++----
> >>>  include/linux/usb/otg.h                           |  7 ++++++-
> >>>  3 files changed, 22 insertions(+), 5 deletions(-)
> >>>
> >>> diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt
> >>> index f6866c1..1db1c33 100644
> >>> --- a/Documentation/devicetree/bindings/usb/generic.txt
> >>> +++ b/Documentation/devicetree/bindings/usb/generic.txt
> >>> @@ -27,6 +27,9 @@ Optional properties:
> >>>   - otg-controller: phandle to otg controller. Host or gadget controllers can
> >>>  			contain this property to link it to a particular OTG
> >>>  			controller.
> >>> + - hcd-needs-companion: must be present if otg controller is dealing with
> >>> +			EHCI host controller that needs a companion OHCI host
> >>> +			controller.
> >>>
> >>>  This is an attribute to a USB controller such as:
> >>>
> >>> diff --git a/drivers/usb/common/usb-otg.c b/drivers/usb/common/usb-otg.c
> >>> index 41e762a..83c8c96 100644
> >>> --- a/drivers/usb/common/usb-otg.c
> >>> +++ b/drivers/usb/common/usb-otg.c
> >>> @@ -20,6 +20,7 @@
> >>>  #include <linux/list.h>
> >>>  #include <linux/of.h>
> >>>  #include <linux/of_platform.h>
> >>> +#include <linux/usb/of.h>
> >>>  #include <linux/usb/otg.h>
> >>>  #include <linux/usb/gadget.h>
> >>>  #include <linux/workqueue.h>
> >>> @@ -600,6 +601,10 @@ struct usb_otg *usb_otg_register(struct device *dev,
> >>>  	else
> >>>  		INIT_WORK(&otg->work, usb_otg_work);
> >>>
> >>> +	if (of_find_property(dev->of_node, "hcd-needs-companion", NULL) ||
> >>> +	    config->hcd_needs_companion)	/* needs comanion ? */
> >>
> >> %s/comanion/companion
> > 
> > Thank you for pointing it out!
> > 
> > Roger, would you fix this in your v7 patch set?
> 
> Yes, I'll fix it locally. You don't need to post it again.
> 

Roger, I am ok with this patch.

Acked-by: Peter Chen <peter.chen@nxp.com>

Peter
> --
> cheers,
> -roger
> 
> > 
> >> I have a little puzzled with companion controller and shared hcd, let me
> >> post a topic for it.
> > 
> > I looked at the email thread.
> > It is very useful information to me! :)
> > 
> > Best regards,
> > Yoshihiro Shimoda
> > 
> >> Peter
> >>
> >>> +		otg->flags |= OTG_FLAG_HCD_NEEDS_COMPANION;
> >>> +
> >>>  	otg->wq = create_singlethread_workqueue("usb_otg");
> >>>  	if (!otg->wq) {
> >>>  		dev_err(dev, "otg: %s: can't create workqueue\n",
> >>> @@ -823,13 +828,15 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum,
> >>>  	/* HCD will be started by OTG fsm when needed */
> >>>  	mutex_lock(&otg->fsm.lock);
> >>>  	if (otg->primary_hcd.hcd) {
> >>> -		/* probably a shared HCD ? */
> >>> -		if (usb_otg_hcd_is_primary_hcd(hcd)) {
> >>> +		/* probably a shared HCD or a companion OHCI HCD ? */
> >>> +		if (!(otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION) &&
> >>> +		    usb_otg_hcd_is_primary_hcd(hcd)) {
> >>>  			dev_err(otg_dev, "otg: primary host already registered\n");
> >>>  			goto err;
> >>>  		}
> >>>
> >>> -		if (hcd->shared_hcd == otg->primary_hcd.hcd) {
> >>> +		if (otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION ||
> >>> +		    (hcd->shared_hcd == otg->primary_hcd.hcd)) {
> >>>  			if (otg->shared_hcd.hcd) {
> >>>  				dev_err(otg_dev, "otg: shared host already registered\n");
> >>>  				goto err;
> >>> @@ -865,7 +872,9 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum,
> >>>  	 * we're ready only if we have shared HCD
> >>>  	 * or we don't need shared HCD.
> >>>  	 */
> >>> -	if (otg->shared_hcd.hcd || !otg->primary_hcd.hcd->shared_hcd) {
> >>> +	if (otg->shared_hcd.hcd ||
> >>> +	    (!(otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION) &&
> >>> +	     !otg->primary_hcd.hcd->shared_hcd)) {
> >>>  		otg->host = hcd_to_bus(hcd);
> >>>  		/* FIXME: set bus->otg_port if this is true OTG port with HNP */
> >>>
> >>> diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h
> >>> index b094352..6f4ca77 100644
> >>> --- a/include/linux/usb/otg.h
> >>> +++ b/include/linux/usb/otg.h
> >>> @@ -57,7 +57,8 @@ struct otg_hcd {
> >>>   * @list: list of otg controllers
> >>>   * @work: otg state machine work
> >>>   * @wq: otg state machine work queue
> >>> - * @flags: to track if host/gadget is running
> >>> + * @flags: to track if host/gadget is running, or to indicate if hcd needs
> >>> + *	   companion
> >>>   */
> >>>  struct usb_otg {
> >>>  	u8			default_a;
> >>> @@ -84,6 +85,7 @@ struct usb_otg {
> >>>  	u32 flags;
> >>>  #define OTG_FLAG_GADGET_RUNNING (1 << 0)
> >>>  #define OTG_FLAG_HOST_RUNNING (1 << 1)
> >>> +#define OTG_FLAG_HCD_NEEDS_COMPANION (1 << 2)
> >>>  	/* use otg->fsm.lock for serializing access */
> >>>
> >>>  /*------------- deprecated interface -----------------------------*/
> >>> @@ -125,11 +127,14 @@ struct usb_otg_caps {
> >>>   * @caps: otg capabilities of the controller
> >>>   * @ops: otg fsm operations
> >>>   * @otg_work: optional custom otg state machine work function
> >>> + * @hcd_needs_companion: Indicates if host controller needs a companion
> >>> + *			 controller
> >>>   */
> >>>  struct usb_otg_config {
> >>>  	struct usb_otg_caps *otg_caps;
> >>>  	struct otg_fsm_ops *fsm_ops;
> >>>  	void (*otg_work)(struct work_struct *work);
> >>> +	bool hcd_needs_companion;
> >>>  };
> >>>
> >>>  extern const char *usb_otg_state_string(enum usb_otg_state state);
> >>> --
> >>> 1.9.1
> >>>
> >>> --
> >>> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> >>> the body of a message to majordomo@vger.kernel.org
> >>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> >>
> >> --
> >>
> >> Best Regards,
> >> Peter Chen

-- 

Best Regards,
Peter Chen