ENGR00212992 usb: fix potential bug with fast plug in/out with usb charger

- Move imx_usb_vbus_disconnect to work queue, and wait or cancel
charger detect worker when vbus is disconnected if charger detect
worker still hasn't finished.
- Move pull down dp from imx_usb_vbus_disconnect to udc vbus
disconnect interrupt handler, the reason is udc->gadget.speed should
to be updated at that ISR.
- Select POWER_SUPPLY if USB_GADGET_ARC is configured to fix the build
error for manufacture tools firmware's build.

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

3 files changed, 12 insertions, 10 deletions

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index 43006e49d903..085c709bc65f 100755
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -159,6 +159,7 @@ config USB_GADGET_ARC
 	depends on ARCH_MXC || ARCH_STMP3XXX || ARCH_MXS
 	select USB_GADGET_DUALSPEED
 	select USB_OTG_UTILS
+	select POWER_SUPPLY
 	help
 	   Some Freescale processors have a USBOTG controller,
 	   which supports device mode.
diff --git a/drivers/usb/gadget/arcotg_udc.c b/drivers/usb/gadget/arcotg_udc.c
index 8def72278d19..90eb9864b0a8 100755
--- a/drivers/usb/gadget/arcotg_udc.c
+++ b/drivers/usb/gadget/arcotg_udc.c
@@ -491,7 +491,6 @@ static void dr_controller_run(struct fsl_udc *udc)
 	if (!(temp & OTGSC_B_SESSION_VALID)) {
 		/* Set stopped before low power mode */
 		udc->vbus_active = false;
-		imx_usb_vbus_disconnect(&udc->charger); /* charger disconnect */
 		udc->stopped = 1;
 		/* enable wake up */
 		dr_wake_up_enable(udc, true);
@@ -513,7 +512,8 @@ static void dr_controller_run(struct fsl_udc *udc)
 		/* disable pulldown dp and dm */
 		dr_discharge_line(udc->pdata, false);
 		udc->vbus_active = true;
-		imx_usb_vbus_connect(&udc->charger); /* charger detect */
+		/* notify vbus is connected */
+		imx_usb_vbus_connect(&udc->charger);
 		printk(KERN_DEBUG "%s: udc out low power mode\n", __func__);
 	}
 
@@ -2182,9 +2182,10 @@ static void fsl_gadget_disconnect_event(struct work_struct *work)
 
 	pdata = udc->pdata;
 
+	 /* notify vbus is disconnected */
+	imx_usb_vbus_disconnect(&udc->charger);
 	/* wait line to se0 */
 	dr_discharge_line(pdata, true);
-
 	/*
 	 * Wait class drivers finish, an well-behaviour class driver should
 	 * call ep_disable when it is notified to be disconnected.
@@ -2242,11 +2243,12 @@ bool try_wake_up_udc(struct fsl_udc *udc)
 			udc->stopped = 0;
 			/* disable pulldown dp and dm */
 			dr_discharge_line(pdata, false);
-			imx_usb_vbus_connect(&udc->charger); /* charger detect */
+			/* notify vbus is connected */
+			imx_usb_vbus_connect(&udc->charger);
 			printk(KERN_DEBUG "%s: udc out low power mode\n", __func__);
 		} else {
 			udc->vbus_active = false;
-			imx_usb_vbus_disconnect(&udc->charger); /* charger disconnect */
+			fsl_pullup(&udc_controller->gadget, false); /* usbcmd.rs=0 */
 			/* here we need disable B_SESSION_IRQ, after
 			 * schedule_work finished, it need to be enabled again.
 			 * Doing like this can avoid conflicting between rapid
@@ -2257,7 +2259,6 @@ bool try_wake_up_udc(struct fsl_udc *udc)
 				fsl_writel(tmp &
 					   (~OTGSC_B_SESSION_VALID_IRQ_EN),
 					   &dr_regs->otgsc);
-
 			/* update port status */
 			fsl_udc_speed_update(udc);
 			spin_unlock(&udc->lock);
diff --git a/drivers/usb/gadget/imx_usb_charger.c b/drivers/usb/gadget/imx_usb_charger.c
index 41043b432102..e1020421adb8 100644
--- a/drivers/usb/gadget/imx_usb_charger.c
+++ b/drivers/usb/gadget/imx_usb_charger.c
@@ -178,7 +178,7 @@ static int usb_charger_detect(struct usb_charger *charger)
 	return 1;
 }
 
-void usb_charger_init(struct usb_charger *charger)
+static void usb_charger_init(struct usb_charger *charger)
 {
 	charger->bc = BATTERY_CHARGING_SPEC_1_2;
 	charger->detect = usb_charger_detect;
@@ -298,12 +298,12 @@ EXPORT_SYMBOL(imx_usb_vbus_connect);
  */
 int imx_usb_vbus_disconnect(struct usb_charger *charger)
 {
-	if (charger->dp_pullup)
-		charger->dp_pullup(false); /* usbcmd.rs = 0 */
-
 	if (!charger->enable)
 		return 0;
 
+	/* in case, the charger detect is doing or pending */
+	cancel_work_sync(&charger->work);
+
 	charger->online = 0;
 	charger->present = 0;
 	charger->max_current = 0;