ENGR00134154-3 usb: add sync between usb resume and usb wakeup thread

The usb wakeup thread should be prior to usb system resume
during usb wakeup process. It adds wait_event_interruptible
at usb resume process, and the usb wakeup irq will set event,
and the usb wakeup thread will clear event.

Signed-off-by: Peter Chen <peter.chen@freescale.com>

4 files changed, 47 insertions, 32 deletions

diff --git a/drivers/usb/gadget/arcotg_udc.c b/drivers/usb/gadget/arcotg_udc.c
index 2539c3eb6495..86b8900bc48f 100644
--- a/drivers/usb/gadget/arcotg_udc.c
+++ b/drivers/usb/gadget/arcotg_udc.c
@@ -491,8 +491,6 @@ static void dr_controller_run(struct fsl_udc *udc)
 
 	/* enable BSV irq */
 	temp = fsl_readl(&dr_regs->otgsc);
-	/* do not clear otgsc interrupt status */
-	temp &= (~(OTGSC_ID_CHANGE_IRQ_STS | OTGSC_B_SESSION_VALID_IRQ_STS));
 	temp |= OTGSC_B_SESSION_VALID_IRQ_EN;
 	fsl_writel(temp, &dr_regs->otgsc);
 
@@ -3160,8 +3158,15 @@ static int fsl_udc_suspend(struct platform_device *pdev, pm_message_t state)
  *-----------------------------------------------------------------*/
 static int fsl_udc_resume(struct platform_device *pdev)
 {
+	struct fsl_usb2_platform_data *pdata = udc_controller->pdata;
+	struct fsl_usb2_wakeup_platform_data *wake_up_pdata = pdata->wakeup_pdata;
 	printk(KERN_DEBUG "USB Gadget resume begins\n");
 
+	if (pdev->dev.power.status == DPM_RESUMING) {
+		printk(KERN_DEBUG "%s, Wait for wakeup thread finishes\n", __func__);
+		wait_event_interruptible(wake_up_pdata->wq, !wake_up_pdata->usb_wakeup_is_pending);
+	}
+
 	pr_debug("%s(): stopped %d  suspended %d\n", __func__,
 		 udc_controller->stopped, udc_controller->suspended);
 #ifdef CONFIG_USB_OTG
@@ -3183,7 +3188,9 @@ static int fsl_udc_resume(struct platform_device *pdev)
 
 	/* Enable DR irq reg and set controller Run */
 	if (udc_controller->stopped) {
-		dr_clk_gate(true);
+		/* the clock is already on at usb wakeup routine */
+		if (pdata->lowpower)
+			dr_clk_gate(true);
 		dr_wake_up_enable(udc_controller, false);
 		dr_phy_low_power_mode(udc_controller, false);
 		mdelay(3);/* IC have the debounce for ID\vbus status in otgsc */
diff --git a/drivers/usb/host/ehci-arc.c b/drivers/usb/host/ehci-arc.c
index 20416da6d75f..615e76572eed 100644
--- a/drivers/usb/host/ehci-arc.c
+++ b/drivers/usb/host/ehci-arc.c
@@ -240,8 +240,9 @@ int usb_hcd_fsl_probe(const struct hc_driver *driver,
 	if (retval != 0)
 		goto err5;
 
+#if (!defined CONFIG_USB_OTG)
 	fsl_platform_set_vbus_power(pdata, 1);
-
+#endif
 	if (pdata->operating_mode == FSL_USB2_DR_OTG) {
 		struct ehci_hcd *ehci = hcd_to_ehci(hcd);
 
@@ -609,10 +610,6 @@ static int ehci_fsl_drv_suspend(struct platform_device *pdev,
 		return 0;
 	}
 
-	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
-		fsl_usb_clk_gate(hcd->self.controller->platform_data, true);
-		set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
-	}
 	/* only the otg host can go here */
 	/* wait for all usb device on the hcd dettached */
 	usb_lock_device(roothub);
@@ -642,7 +639,10 @@ static int ehci_fsl_drv_suspend(struct platform_device *pdev,
 		usb_unlock_device(roothub);
 	}
 
-	pr_debug("%s: suspending...\n", __func__);
+	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
+		fsl_usb_clk_gate(hcd->self.controller->platform_data, true);
+		set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+	}
 
 	port_status = ehci_readl(ehci, &ehci->regs->port_status[0]);
 	/* save EHCI registers */
@@ -682,10 +682,12 @@ static int ehci_fsl_drv_resume(struct platform_device *pdev)
 	struct usb_device *roothub = hcd->self.root_hub;
 	u32 tmp;
 	struct fsl_usb2_platform_data *pdata = pdev->dev.platform_data;
+	struct fsl_usb2_wakeup_platform_data *wake_up_pdata = pdata->wakeup_pdata;
 	/* Only handles OTG mode switch event */
 	printk(KERN_DEBUG "ehci fsl drv resume begins: %s\n", pdata->name);
 	if (pdev->dev.power.status == DPM_RESUMING) {
-		printk(KERN_DEBUG "%s, pm event \n", __func__);
+		printk(KERN_DEBUG "%s,pm event, wait for wakeup irq if needed\n", __func__);
+		wait_event_interruptible(wake_up_pdata->wq, !wake_up_pdata->usb_wakeup_is_pending);
 		if (!host_can_wakeup_system(pdev)) {
 			if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
 				fsl_usb_clk_gate(hcd->self.controller->platform_data, true);
diff --git a/drivers/usb/otg/fsl_otg.c b/drivers/usb/otg/fsl_otg.c
index eccd173b33e4..e32d7cab828e 100644
--- a/drivers/usb/otg/fsl_otg.c
+++ b/drivers/usb/otg/fsl_otg.c
@@ -445,8 +445,16 @@ static void fsl_otg_loading_monitor(unsigned long data)
  */
 static void b_session_irq_enable(bool enable)
 {
-	int osc = le32_to_cpu(usb_dr_regs->otgsc);
-	pr_debug("%s:enable=%d", __func__, enable);
+	u32 osc;
+	fsl_otg_clk_gate(true);
+	if (le32_to_cpu(usb_dr_regs->portsc) & PORTSC_PHY_LOW_POWER_SPD) {
+		pr_debug("%s: the usb is in low power mode, vbus should not changed \n", __func__);
+		fsl_otg_clk_gate(false);
+		return;
+	}
+
+	osc = le32_to_cpu(usb_dr_regs->otgsc);
+	pr_debug("%s:otgsc=0x%x", __func__, osc);
 	/* The other interrupts' status should not be cleared */
 	osc &= ~(OTGSC_INTSTS_USB_ID | OTGSC_INTSTS_A_VBUS_VALID
 		| OTGSC_INTSTS_A_SESSION_VALID | OTGSC_INTSTS_B_SESSION_VALID);
@@ -456,6 +464,7 @@ static void b_session_irq_enable(bool enable)
 	else
 		osc &= ~OTGSC_INTR_B_SESSION_VALID_EN;
 	usb_dr_regs->otgsc = cpu_to_le32(osc);
+	fsl_otg_clk_gate(false);
 }
 
 /* Reset controller, not reset the bus */
@@ -489,8 +498,11 @@ int fsl_otg_start_host(struct otg_fsm *fsm, int on)
 	/* Update a_vbus_vld state as a_vbus_vld int is disabled
 	 * in device mode
 	 */
+	fsl_otg_clk_gate(true);
 	fsm->a_vbus_vld =
 	    (le32_to_cpu(usb_dr_regs->otgsc) & OTGSC_STS_A_VBUS_VALID) ? 1 : 0;
+	fsl_otg_clk_gate(false);
+
 	if (on) {
 		/* start fsl usb host controller */
 		if (otg_dev->host_working)
@@ -666,14 +678,6 @@ static int fsl_otg_set_peripheral(struct otg_transceiver *otg_p,
 	if (otg_dev->fsm.id == 1) {
 		fsl_otg_start_host(&otg_dev->fsm, 0);
 		otg_drv_vbus(&otg_dev->fsm, 0);
-		/* Clear OTGSC_INTSTS_B_SESSION_VALID
-		 * When the host driver loads, the vbus may change to 5v for some
-		 * SoC's. But when there is no usb device at host port, the vbus
-		 * will be off, in that case, vbus changes status will be set.
-		 */
-		fsl_otg_clk_gate(true);
-		b_session_irq_enable(false);
-		fsl_otg_clk_gate(false);
 		fsl_otg_start_gadget(&otg_dev->fsm, 1);
 	}
 
@@ -707,6 +711,7 @@ static void fsl_otg_event(struct work_struct *work)
 	struct otg_transceiver *otg = &og->otg;
 
 	mutex_lock(&pm_mutex);
+	b_session_irq_enable(false);
 	otg->default_a = (fsm->id == 0);
 	/* clear conn information */
 	if (fsm->id)
@@ -722,10 +727,12 @@ static void fsl_otg_event(struct work_struct *work)
 	if (fsm->id) {		/* switch to gadget */
 		fsl_otg_start_host(fsm, 0);
 		otg_drv_vbus(fsm, 0);
+		b_session_irq_enable(false);
 		fsl_otg_start_gadget(fsm, 1);
 	} else {			/* switch to host */
 		fsl_otg_start_gadget(fsm, 0);
 		otg_drv_vbus(fsm, 1);
+		b_session_irq_enable(false);
 		fsl_otg_start_host(fsm, 1);
 	}
 	mutex_unlock(&pm_mutex);
@@ -791,12 +798,6 @@ irqreturn_t fsl_otg_isr_gpio(int irq, void *dev_id)
 
 	cancel_delayed_work(&f_otg->otg_event);
 	schedule_otg_work(&f_otg->otg_event, msecs_to_jiffies(10));
-	/* if host mode, we should clear B_SESSION_VLD event and disable
-	 * B_SESSION_VLD irq
-	 */
-	if (!f_otg->fsm.id) {
-		b_session_irq_enable(false);
-	}
 
 	return IRQ_HANDLED;
 }
@@ -841,12 +842,6 @@ irqreturn_t fsl_otg_isr(int irq, void *dev_id)
 
 			cancel_delayed_work(&fotg->otg_event);
 			schedule_otg_work(&fotg->otg_event, msecs_to_jiffies(10));
-			/* if host mode, we should clear B_SESSION_VLD event and disable
-			 * B_SESSION_VLD irq
-			 */
-			if (!fotg->fsm.id) {
-				b_session_irq_enable(false);
-			}
 			ret = IRQ_HANDLED;
 		}
 	}
diff --git a/include/linux/fsl_devices.h b/include/linux/fsl_devices.h
index 5d7828041332..4f68788c55e0 100644
--- a/include/linux/fsl_devices.h
+++ b/include/linux/fsl_devices.h
@@ -67,6 +67,7 @@ enum fsl_usb2_phy_modes {
 	FSL_USB2_PHY_SERIAL,
 };
 
+struct fsl_usb2_wakeup_platform_data;
 struct platform_device;
 struct fsl_usb2_platform_data {
 	/* board specific information */
@@ -105,6 +106,7 @@ struct fsl_usb2_platform_data {
 	unsigned            lowpower:1;
 	unsigned            irq_delay:1;
 	unsigned            wakeup_event:1;
+	struct fsl_usb2_wakeup_platform_data *wakeup_pdata;
 
 	u32				id_gpio;
 	/* register save area for suspend/resume */
@@ -127,6 +129,15 @@ struct fsl_usb2_wakeup_platform_data {
 	char *name;
 	void (*usb_clock_for_pm) (bool);
 	struct fsl_usb2_platform_data *usb_pdata[3];
+	/* This waitqueue is used to wait "usb_wakeup thread" to finish
+	 * during system resume routine. "usb_wakeup theard" should be finished
+	 * prior to usb resume routine.
+	 */
+	wait_queue_head_t wq;
+	/* This flag is used to indicate the "usb_wakeup thread" is finished during
+	 * usb wakeup routine.
+	 */
+	bool usb_wakeup_is_pending;
 };