usb: chipidea: add vbus interrupt handler

We add vbus interrupt handler at ci_otg_work, it uses OTGSC_BSV(at otgsc)
to know it is connect or disconnet event.
Meanwhile, we introduce two flags id_event and b_sess_valid_event to
indicate it is an id interrupt or a vbus interrupt.
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/chipidea/ci.h

@@ -132,6 +132,9 @@ struct hw_bank {
  * @transceiver: pointer to USB PHY, if any
  * @hcd: pointer to usb_hcd for ehci host driver
  * @debugfs: root dentry for this controller in debugfs
+ * @id_event: indicates there is an id event, and handled at ci_otg_work
+ * @b_sess_valid_event: indicates there is a vbus event, and handled
+ * at ci_otg_work
  */
 struct ci_hdrc {
 	struct device			*dev;
@@ -168,6 +171,8 @@ struct ci_hdrc {
 	struct usb_phy			*transceiver;
 	struct usb_hcd			*hcd;
 	struct dentry			*debugfs;
+	bool				id_event;
+	bool				b_sess_valid_event;
 };
 
 static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci)

drivers/usb/chipidea/core.c

@@ -303,16 +303,34 @@ static irqreturn_t ci_irq(int irq, void *data)
 	if (ci->is_otg)
 		otgsc = hw_read(ci, OP_OTGSC, ~0);
 
-	if (ci->role != CI_ROLE_END)
-		ret = ci_role(ci)->irq(ci);
+	/*
+	 * Handle id change interrupt, it indicates device/host function
+	 * switch.
+	 */
+	if (ci->is_otg && (otgsc & OTGSC_IDIE) && (otgsc & OTGSC_IDIS)) {
+		ci->id_event = true;
+		ci_clear_otg_interrupt(ci, OTGSC_IDIS);
+		disable_irq_nosync(ci->irq);
+		queue_work(ci->wq, &ci->work);
+		return IRQ_HANDLED;
+	}
 
-	if (ci->is_otg && (otgsc & OTGSC_IDIS)) {
-		hw_write(ci, OP_OTGSC, OTGSC_IDIS, OTGSC_IDIS);
+	/*
+	 * Handle vbus change interrupt, it indicates device connection
+	 * and disconnection events.
+	 */
+	if (ci->is_otg && (otgsc & OTGSC_BSVIE) && (otgsc & OTGSC_BSVIS)) {
+		ci->b_sess_valid_event = true;
+		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
 		disable_irq_nosync(ci->irq);
 		queue_work(ci->wq, &ci->work);
-		ret = IRQ_HANDLED;
+		return IRQ_HANDLED;
 	}
 
+	/* Handle device/host interrupt */
+	if (ci->role != CI_ROLE_END)
+		ret = ci_role(ci)->irq(ci);
+
 	return ret;
 }
 

drivers/usb/chipidea/otg.c

@@ -37,13 +37,23 @@ enum ci_role ci_otg_role(struct ci_hdrc *ci)
 	return role;
 }
 
-/**
- * ci_role_work - perform role changing based on ID pin
- * @work: work struct
- */
-static void ci_role_work(struct work_struct *work)
+void ci_handle_vbus_change(struct ci_hdrc *ci)
+{
+	u32 otgsc;
+
+	if (!ci->is_otg)
+		return;
+
+	otgsc = hw_read(ci, OP_OTGSC, ~0);
+
+	if (otgsc & OTGSC_BSV)
+		usb_gadget_vbus_connect(&ci->gadget);
+	else
+		usb_gadget_vbus_disconnect(&ci->gadget);
+}
+
+static void ci_handle_id_switch(struct ci_hdrc *ci)
 {
-	struct ci_hdrc *ci = container_of(work, struct ci_hdrc, work);
 	enum ci_role role = ci_otg_role(ci);
 
 	if (role != ci->role) {
@@ -53,17 +63,35 @@ static void ci_role_work(struct work_struct *work)
 		ci_role_stop(ci);
 		ci_role_start(ci, role);
 	}
+}
+/**
+ * ci_otg_work - perform otg (vbus/id) event handle
+ * @work: work struct
+ */
+static void ci_otg_work(struct work_struct *work)
+{
+	struct ci_hdrc *ci = container_of(work, struct ci_hdrc, work);
+
+	if (ci->id_event) {
+		ci->id_event = false;
+		ci_handle_id_switch(ci);
+	} else if (ci->b_sess_valid_event) {
+		ci->b_sess_valid_event = false;
+		ci_handle_vbus_change(ci);
+	} else
+		dev_err(ci->dev, "unexpected event occurs at %s\n", __func__);
 
 	enable_irq(ci->irq);
 }
 
+
 /**
  * ci_hdrc_otg_init - initialize otg struct
  * ci: the controller
  */
 int ci_hdrc_otg_init(struct ci_hdrc *ci)
 {
-	INIT_WORK(&ci->work, ci_role_work);
+	INIT_WORK(&ci->work, ci_otg_work);
 	ci->wq = create_singlethread_workqueue("ci_otg");
 	if (!ci->wq) {
 		dev_err(ci->dev, "can't create workqueue\n");

drivers/usb/chipidea/otg.h

@@ -30,5 +30,6 @@ static inline void ci_disable_otg_interrupt(struct ci_hdrc *ci, u32 bits)
 int ci_hdrc_otg_init(struct ci_hdrc *ci);
 void ci_hdrc_otg_destroy(struct ci_hdrc *ci);
 enum ci_role ci_otg_role(struct ci_hdrc *ci);
+void ci_handle_vbus_change(struct ci_hdrc *ci);
 
 #endif /* __DRIVERS_USB_CHIPIDEA_OTG_H */

drivers/usb/chipidea/udc.c

@@ -85,8 +85,10 @@ static int hw_device_state(struct ci_hdrc *ci, u32 dma)
 		/* interrupt, error, port change, reset, sleep/suspend */
 		hw_write(ci, OP_USBINTR, ~0,
 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
+		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
 	} else {
 		hw_write(ci, OP_USBINTR, ~0, 0);
+		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
 	}
 	return 0;
 }
@@ -1460,6 +1462,7 @@ static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
 			pm_runtime_get_sync(&_gadget->dev);
 			hw_device_reset(ci, USBMODE_CM_DC);
 			hw_device_state(ci, ci->ep0out->qh.dma);
+			dev_dbg(ci->dev, "Connected to host\n");
 		} else {
 			hw_device_state(ci, 0);
 			if (ci->platdata->notify_event)
@@ -1467,6 +1470,7 @@ static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
 			_gadget_stop_activity(&ci->gadget);
 			pm_runtime_put_sync(&_gadget->dev);
+			dev_dbg(ci->dev, "Disconnected from host\n");
 		}
 	}
 
@@ -1822,6 +1826,9 @@ static int udc_start(struct ci_hdrc *ci)
 	pm_runtime_no_callbacks(&ci->gadget.dev);
 	pm_runtime_enable(&ci->gadget.dev);
 
+	/* Update ci->vbus_active */
+	ci_handle_vbus_change(ci);
+
 	return retval;
 
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