> -----Original Message-----
> From: Peter Chen <hzpeterchen@xxxxxxxxx>
> Sent: 2019年8月2日 17:41
> 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.
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
> >
