usb: musb: core: Convert babble recover work to delayed work

During babble condition both first disconnect of devices are
initiated. Make sure MUSB controller is reset and re-initialized
after all disconnects.

To acheive this schedule a delayed work for babble recovery.

While at that convert udelay to usleep_range.
Refer Documentation/timers/timers-howto.txt
Signed-off-by: George Cherian <george.cherian@ti.com>
Tested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/musb/musb_core.c

@@ -850,7 +850,8 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb,
 
 	/* handle babble condition */
 	if (int_usb & MUSB_INTR_BABBLE && is_host_active(musb))
-		schedule_work(&musb->recover_work);
+		schedule_delayed_work(&musb->recover_work,
+				      msecs_to_jiffies(100));
 
 #if 0
 /* REVISIT ... this would be for multiplexing periodic endpoints, or
@@ -1751,16 +1752,16 @@ static void musb_irq_work(struct work_struct *data)
 /* Recover from babble interrupt conditions */
 static void musb_recover_work(struct work_struct *data)
 {
-	struct musb *musb = container_of(data, struct musb, recover_work);
+	struct musb *musb = container_of(data, struct musb, recover_work.work);
 	int status;
 
 	musb_platform_reset(musb);
 
 	usb_phy_vbus_off(musb->xceiv);
-	udelay(100);
+	usleep_range(100, 200);
 
 	usb_phy_vbus_on(musb->xceiv);
-	udelay(100);
+	usleep_range(100, 200);
 
 	/*
 	 * When a babble condition occurs, the musb controller removes the
@@ -1943,7 +1944,7 @@ musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl)
 
 	/* Init IRQ workqueue before request_irq */
 	INIT_WORK(&musb->irq_work, musb_irq_work);
-	INIT_WORK(&musb->recover_work, musb_recover_work);
+	INIT_DELAYED_WORK(&musb->recover_work, musb_recover_work);
 	INIT_DELAYED_WORK(&musb->deassert_reset_work, musb_deassert_reset);
 	INIT_DELAYED_WORK(&musb->finish_resume_work, musb_host_finish_resume);
 
@@ -2039,7 +2040,7 @@ musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl)
 
 fail3:
 	cancel_work_sync(&musb->irq_work);
-	cancel_work_sync(&musb->recover_work);
+	cancel_delayed_work_sync(&musb->recover_work);
 	cancel_delayed_work_sync(&musb->finish_resume_work);
 	cancel_delayed_work_sync(&musb->deassert_reset_work);
 	if (musb->dma_controller)
@@ -2105,7 +2106,7 @@ static int musb_remove(struct platform_device *pdev)
 		dma_controller_destroy(musb->dma_controller);
 
 	cancel_work_sync(&musb->irq_work);
-	cancel_work_sync(&musb->recover_work);
+	cancel_delayed_work_sync(&musb->recover_work);
 	cancel_delayed_work_sync(&musb->finish_resume_work);
 	cancel_delayed_work_sync(&musb->deassert_reset_work);
 	musb_free(musb);

drivers/usb/musb/musb_core.h

@@ -297,7 +297,7 @@ struct musb {
 
 	irqreturn_t		(*isr)(int, void *);
 	struct work_struct	irq_work;
-	struct work_struct	recover_work;
+	struct delayed_work	recover_work;
 	struct delayed_work	deassert_reset_work;
 	struct delayed_work	finish_resume_work;
 	u16			hwvers;