> -----Original Message-----
> From: Peter Chen <hzpeterchen@xxxxxxxxx>
> Sent: 2019年8月5日 11:15
> To: Jun Li <jun.li@xxxxxxx>
> Cc: Peter Chen <peter.chen@xxxxxxx>; Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx>; dl-linux-imx <linux-imx@xxxxxxx>; USB list
> <linux-usb@xxxxxxxxxxxxxxx>
> Subject: Re: [PATCH 2/5] usb: chipidea: add role switch class support
>
> > >
> > > > USB role is fully controlled by usb role switch consumer(e.g.
> > > > typec), usb port either at host mode, or at device connected mode,
> > > > will not stay at USB_ROLE_NONE mode.
> > > >
> > >
> > > Then, if the Type-C cable is disconnected from PC host, the
> > > controller driver can't be notified?If that, how controller enters low power mode at this
> situation?
> >
> > The controller driver can be notified, but there are only role(host or
> > device) Information, so in you mentioned case, controller driver will
> > get the same input before and after disconnect from host, can't know
> > detachment and enter low power mode accordingly, this is more like
> > something internal handling under device role.
> >
>
> If the Type-C can't pass "gadget disconnect" event, you may handle it at UDC driver itself,
> eg at ci_usb_role_switch_set. Otherwise, the gadget class driver can't be notified
> disconnection, and the controller itself can't enter LPM as well.
OK, I will enable VBUS irq to handle this in v2.
Li Jun
>
> Peter
>
> > Li Jun
> >
> > >
> > > Peter
> > >
> > > > Signed-off-by: Li Jun <jun.li@xxxxxxx>
> > > > ---
> > > > drivers/usb/chipidea/ci.h | 2 +
> > > > drivers/usb/chipidea/core.c | 125
> > > > ++++++++++++++++++++++++++++++++++----------
> > > > drivers/usb/chipidea/otg.c | 13 +++++
> > > > 3 files changed, 111 insertions(+), 29 deletions(-)
> > > >
> > > > diff --git a/drivers/usb/chipidea/ci.h b/drivers/usb/chipidea/ci.h
> > > > index 82b86cd..5e2f0bc 100644
> > > > --- a/drivers/usb/chipidea/ci.h
> > > > +++ b/drivers/usb/chipidea/ci.h
> > > > @@ -212,6 +212,7 @@ struct ci_hdrc {
> > > > ktime_t
> hr_timeouts[NUM_OTG_FSM_TIMERS];
> > > > unsigned enabled_otg_timer_bits;
> > > > enum otg_fsm_timer next_otg_timer;
> > > > + struct usb_role_switch *role_switch;
> > > > struct work_struct work;
> > > > struct workqueue_struct *wq;
> > > >
> > > > @@ -244,6 +245,7 @@ struct ci_hdrc {
> > > > struct dentry *debugfs;
> > > > bool id_event;
> > > > bool b_sess_valid_event;
> > > > + bool role_switch_event;
> > > > bool imx28_write_fix;
> > > > bool supports_runtime_pm;
> > > > bool in_lpm;
> > > > diff --git a/drivers/usb/chipidea/core.c
> > > > b/drivers/usb/chipidea/core.c index bc24c5b..1bcf6f6 100644
> > > > --- a/drivers/usb/chipidea/core.c
> > > > +++ b/drivers/usb/chipidea/core.c
> > > > @@ -587,6 +587,47 @@ static irqreturn_t ci_irq(int irq, void *data)
> > > > return ret;
> > > > }
> > > >
> > > > +static int ci_usb_role_switch_set(struct device *dev, enum
> > > > +usb_role
> > > > +role) {
> > > > + struct ci_hdrc *ci = dev_get_drvdata(dev);
> > > > + unsigned long flags;
> > > > +
> > > > + if (ci->role == role || role == USB_ROLE_NONE)
> > > > + return 0;
> > > > +
> > > > + spin_lock_irqsave(&ci->lock, flags);
> > > > + ci->role_switch_event = true;
> > > > + if (ci->role == USB_ROLE_NONE) {
> > > > + if (role == USB_ROLE_DEVICE)
> > > > + ci->role = USB_ROLE_HOST;
> > > > + else
> > > > + ci->role = USB_ROLE_DEVICE;
> > > > + }
> > > > + spin_unlock_irqrestore(&ci->lock, flags);
> > > > +
> > > > + ci_otg_queue_work(ci);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static enum usb_role ci_usb_role_switch_get(struct device *dev) {
> > > > + struct ci_hdrc *ci = dev_get_drvdata(dev);
> > > > + unsigned long flags;
> > > > + enum usb_role role;
> > > > +
> > > > + spin_lock_irqsave(&ci->lock, flags);
> > > > + role = ci->role;
> > > > + spin_unlock_irqrestore(&ci->lock, flags);
> > > > +
> > > > + return role;
> > > > +}
> > > > +
> > > > +static struct usb_role_switch_desc ci_role_switch = {
> > > > + .set = ci_usb_role_switch_set,
> > > > + .get = ci_usb_role_switch_get, };
> > > > +
> > > > static int ci_cable_notifier(struct notifier_block *nb, unsigned long event,
> > > > void *ptr) { @@ -689,6 +730,9 @@
> > > > static int ci_get_platdata(struct device *dev,
> > > > if (of_find_property(dev->of_node, "non-zero-ttctrl-ttha", NULL))
> > > > platdata->flags |= CI_HDRC_SET_NON_ZERO_TTHA;
> > > >
> > > > + if (device_property_read_bool(dev, "usb-role-switch"))
> > > > + ci_role_switch.fwnode = dev->fwnode;
> > > > +
> > > > ext_id = ERR_PTR(-ENODEV);
> > > > ext_vbus = ERR_PTR(-ENODEV);
> > > > if (of_property_read_bool(dev->of_node, "extcon")) { @@
> > > > -908,6
> > > > +952,43 @@ static const struct attribute_group ci_attr_group = {
> > > > .attrs = ci_attrs,
> > > > };
> > > >
> > > > +static int ci_start_initial_role(struct ci_hdrc *ci) {
> > > > + int ret = 0;
> > > > +
> > > > + if (ci->roles[USB_ROLE_HOST] && ci->roles[USB_ROLE_DEVICE]) {
> > > > + if (ci->is_otg) {
> > > > + ci->role = ci_otg_role(ci);
> > > > + /* Enable ID change irq */
> > > > + hw_write_otgsc(ci, OTGSC_IDIE, OTGSC_IDIE);
> > > > + } else {
> > > > + /*
> > > > + * If the controller is not OTG capable, but support
> > > > + * role switch, the defalt role is gadget, and the
> > > > + * user can switch it through debugfs.
> > > > + */
> > > > + ci->role = USB_ROLE_DEVICE;
> > > > + }
> > > > + } else {
> > > > + ci->role = ci->roles[USB_ROLE_HOST]
> > > > + ? USB_ROLE_HOST
> > > > + : USB_ROLE_DEVICE;
> > > > + }
> > > > +
> > > > + if (!ci_otg_is_fsm_mode(ci)) {
> > > > + /* only update vbus status for peripheral */
> > > > + if (ci->role == USB_ROLE_DEVICE)
> > > > + ci_handle_vbus_change(ci);
> > > > +
> > > > + ret = ci_role_start(ci, ci->role);
> > > > + if (ret)
> > > > + dev_err(ci->dev, "can't start %s role\n",
> > > > + ci_role(ci)->name);
> > > > + }
> > > > +
> > > > + return ret;
> > > > +}
> > > > +
> > > > static int ci_hdrc_probe(struct platform_device *pdev) {
> > > > struct device *dev = &pdev->dev;
> > > > @@ -1051,36 +1132,10 @@ static int ci_hdrc_probe(struct platform_device *pdev)
> > > > }
> > > > }
> > > >
> > > > - if (ci->roles[USB_ROLE_HOST] && ci->roles[USB_ROLE_DEVICE]) {
> > > > - if (ci->is_otg) {
> > > > - ci->role = ci_otg_role(ci);
> > > > - /* Enable ID change irq */
> > > > - hw_write_otgsc(ci, OTGSC_IDIE, OTGSC_IDIE);
> > > > - } else {
> > > > - /*
> > > > - * If the controller is not OTG capable, but support
> > > > - * role switch, the defalt role is gadget, and the
> > > > - * user can switch it through debugfs.
> > > > - */
> > > > - ci->role = USB_ROLE_DEVICE;
> > > > - }
> > > > - } else {
> > > > - ci->role = ci->roles[USB_ROLE_HOST]
> > > > - ? USB_ROLE_HOST
> > > > - : USB_ROLE_DEVICE;
> > > > - }
> > > > -
> > > > - if (!ci_otg_is_fsm_mode(ci)) {
> > > > - /* only update vbus status for peripheral */
> > > > - if (ci->role == USB_ROLE_DEVICE)
> > > > - ci_handle_vbus_change(ci);
> > > > -
> > > > - ret = ci_role_start(ci, ci->role);
> > > > - if (ret) {
> > > > - dev_err(dev, "can't start %s role\n",
> > > > - ci_role(ci)->name);
> > > > + if (!ci_role_switch.fwnode) {
> > > > + ret = ci_start_initial_role(ci);
> > > > + if (ret)
> > > > goto stop;
> > > > - }
> > > > }
> > > >
> > > > ret = devm_request_irq(dev, ci->irq, ci_irq, IRQF_SHARED,
> > > > @@
> > > > -1092,6 +1147,15 @@ static int ci_hdrc_probe(struct platform_device *pdev)
> > > > if (ret)
> > > > goto stop;
> > > >
> > > > + if (ci_role_switch.fwnode) {
> > > > + ci->role_switch = usb_role_switch_register(dev,
> > > > + &ci_role_switch);
> > > > + if (IS_ERR(ci->role_switch)) {
> > > > + ret = PTR_ERR(ci->role_switch);
> > > > + goto stop;
> > > > + }
> > > > + }
> > > > +
> > > > if (ci->supports_runtime_pm) {
> > > > pm_runtime_set_active(&pdev->dev);
> > > > pm_runtime_enable(&pdev->dev); @@ -1133,6 +1197,9
> > > > @@ static int ci_hdrc_remove(struct platform_device *pdev) {
> > > > struct ci_hdrc *ci = platform_get_drvdata(pdev);
> > > >
> > > > + if (ci->role_switch)
> > > > + usb_role_switch_unregister(ci->role_switch);
> > > > +
> > > > if (ci->supports_runtime_pm) {
> > > > pm_runtime_get_sync(&pdev->dev);
> > > > pm_runtime_disable(&pdev->dev); diff --git
> > > > a/drivers/usb/chipidea/otg.c b/drivers/usb/chipidea/otg.c index
> > > > 5bde0b5..0a22855 100644
> > > > --- a/drivers/usb/chipidea/otg.c
> > > > +++ b/drivers/usb/chipidea/otg.c
> > > > @@ -214,6 +214,19 @@ static void ci_otg_work(struct work_struct *work)
> > > > ci_handle_vbus_change(ci);
> > > > }
> > > >
> > > > + if (ci->role_switch_event) {
> > > > + ci->role_switch_event = false;
> > > > +
> > > > + if (ci->role == USB_ROLE_DEVICE) {
> > > > + usb_gadget_vbus_disconnect(&ci->gadget);
> > > > + ci_role_start(ci, USB_ROLE_HOST);
> > > > + } else if (ci->role == USB_ROLE_HOST) {
> > > > + ci_role_stop(ci);
> > > > + usb_gadget_vbus_connect(&ci->gadget);
> > > > + ci->role = USB_ROLE_DEVICE;
> > > > + }
> > > > + }
> > > > +
> > > > pm_runtime_put_sync(ci->dev);
> > > >
> > > > enable_irq(ci->irq);
> > > > --
> > > > 2.7.4
> > > >
