usb: musb: handle irqs in the order dictated by programming guide

MUSB's programming guide dictates how we should handle its
irqs and in which order. Follow that.
Signed-off-by: Arnaud Mandy <ext-arnaud.2.mandy@nokia.com>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/musb/musb_core.c

@@ -557,6 +557,69 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb,
 		handled = IRQ_HANDLED;
 	}
 
+
+	if (int_usb & MUSB_INTR_SUSPEND) {
+		DBG(1, "SUSPEND (%s) devctl %02x power %02x\n",
+				otg_state_string(musb), devctl, power);
+		handled = IRQ_HANDLED;
+
+		switch (musb->xceiv->state) {
+#ifdef	CONFIG_USB_MUSB_OTG
+		case OTG_STATE_A_PERIPHERAL:
+			/* We also come here if the cable is removed, since
+			 * this silicon doesn't report ID-no-longer-grounded.
+			 *
+			 * We depend on T(a_wait_bcon) to shut us down, and
+			 * hope users don't do anything dicey during this
+			 * undesired detour through A_WAIT_BCON.
+			 */
+			musb_hnp_stop(musb);
+			usb_hcd_resume_root_hub(musb_to_hcd(musb));
+			musb_root_disconnect(musb);
+			musb_platform_try_idle(musb, jiffies
+					+ msecs_to_jiffies(musb->a_wait_bcon
+						? : OTG_TIME_A_WAIT_BCON));
+
+			break;
+#endif
+		case OTG_STATE_B_IDLE:
+			if (!musb->is_active)
+				break;
+		case OTG_STATE_B_PERIPHERAL:
+			musb_g_suspend(musb);
+			musb->is_active = is_otg_enabled(musb)
+					&& musb->xceiv->gadget->b_hnp_enable;
+			if (musb->is_active) {
+#ifdef	CONFIG_USB_MUSB_OTG
+				musb->xceiv->state = OTG_STATE_B_WAIT_ACON;
+				DBG(1, "HNP: Setting timer for b_ase0_brst\n");
+				mod_timer(&musb->otg_timer, jiffies
+					+ msecs_to_jiffies(
+							OTG_TIME_B_ASE0_BRST));
+#endif
+			}
+			break;
+		case OTG_STATE_A_WAIT_BCON:
+			if (musb->a_wait_bcon != 0)
+				musb_platform_try_idle(musb, jiffies
+					+ msecs_to_jiffies(musb->a_wait_bcon));
+			break;
+		case OTG_STATE_A_HOST:
+			musb->xceiv->state = OTG_STATE_A_SUSPEND;
+			musb->is_active = is_otg_enabled(musb)
+					&& musb->xceiv->host->b_hnp_enable;
+			break;
+		case OTG_STATE_B_HOST:
+			/* Transition to B_PERIPHERAL, see 6.8.2.6 p 44 */
+			DBG(1, "REVISIT: SUSPEND as B_HOST\n");
+			break;
+		default:
+			/* "should not happen" */
+			musb->is_active = 0;
+			break;
+		}
+	}
+
 	if (int_usb & MUSB_INTR_CONNECT) {
 		struct usb_hcd *hcd = musb_to_hcd(musb);
 
@@ -625,10 +688,61 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb,
 	}
 #endif	/* CONFIG_USB_MUSB_HDRC_HCD */
 
+	if ((int_usb & MUSB_INTR_DISCONNECT) && !musb->ignore_disconnect) {
+		DBG(1, "DISCONNECT (%s) as %s, devctl %02x\n",
+				otg_state_string(musb),
+				MUSB_MODE(musb), devctl);
+		handled = IRQ_HANDLED;
+
+		switch (musb->xceiv->state) {
+#ifdef CONFIG_USB_MUSB_HDRC_HCD
+		case OTG_STATE_A_HOST:
+		case OTG_STATE_A_SUSPEND:
+			usb_hcd_resume_root_hub(musb_to_hcd(musb));
+			musb_root_disconnect(musb);
+			if (musb->a_wait_bcon != 0 && is_otg_enabled(musb))
+				musb_platform_try_idle(musb, jiffies
+					+ msecs_to_jiffies(musb->a_wait_bcon));
+			break;
+#endif	/* HOST */
+#ifdef CONFIG_USB_MUSB_OTG
+		case OTG_STATE_B_HOST:
+			/* REVISIT this behaves for "real disconnect"
+			 * cases; make sure the other transitions from
+			 * from B_HOST act right too.  The B_HOST code
+			 * in hnp_stop() is currently not used...
+			 */
+			musb_root_disconnect(musb);
+			musb_to_hcd(musb)->self.is_b_host = 0;
+			musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
+			MUSB_DEV_MODE(musb);
+			musb_g_disconnect(musb);
+			break;
+		case OTG_STATE_A_PERIPHERAL:
+			musb_hnp_stop(musb);
+			musb_root_disconnect(musb);
+			/* FALLTHROUGH */
+		case OTG_STATE_B_WAIT_ACON:
+			/* FALLTHROUGH */
+#endif	/* OTG */
+#ifdef CONFIG_USB_GADGET_MUSB_HDRC
+		case OTG_STATE_B_PERIPHERAL:
+		case OTG_STATE_B_IDLE:
+			musb_g_disconnect(musb);
+			break;
+#endif	/* GADGET */
+		default:
+			WARNING("unhandled DISCONNECT transition (%s)\n",
+				otg_state_string(musb));
+			break;
+		}
+	}
+
 	/* mentor saves a bit: bus reset and babble share the same irq.
 	 * only host sees babble; only peripheral sees bus reset.
 	 */
 	if (int_usb & MUSB_INTR_RESET) {
+		handled = IRQ_HANDLED;
 		if (is_host_capable() && (devctl & MUSB_DEVCTL_HM) != 0) {
 			/*
 			 * Looks like non-HS BABBLE can be ignored, but
@@ -641,7 +755,7 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb,
 				DBG(1, "BABBLE devctl: %02x\n", devctl);
 			else {
 				ERR("Stopping host session -- babble\n");
-				musb_writeb(mbase, MUSB_DEVCTL, 0);
+				musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
 			}
 		} else if (is_peripheral_capable()) {
 			DBG(1, "BUS RESET as %s\n", otg_state_string(musb));
@@ -686,29 +800,7 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb,
 					otg_state_string(musb));
 			}
 		}
-
-		handled = IRQ_HANDLED;
 	}
-	schedule_work(&musb->irq_work);
-
-	return handled;
-}
-
-/*
- * Interrupt Service Routine to record USB "global" interrupts.
- * Since these do not happen often and signify things of
- * paramount importance, it seems OK to check them individually;
- * the order of the tests is specified in the manual
- *
- * @param musb instance pointer
- * @param int_usb register contents
- * @param devctl
- * @param power
- */
-static irqreturn_t musb_stage2_irq(struct musb *musb, u8 int_usb,
-				u8 devctl, u8 power)
-{
-	irqreturn_t handled = IRQ_NONE;
 
 #if 0
 /* REVISIT ... this would be for multiplexing periodic endpoints, or
@@ -755,117 +847,7 @@ static irqreturn_t musb_stage2_irq(struct musb *musb, u8 int_usb,
 	}
 #endif
 
-	if ((int_usb & MUSB_INTR_DISCONNECT) && !musb->ignore_disconnect) {
-		DBG(1, "DISCONNECT (%s) as %s, devctl %02x\n",
-				otg_state_string(musb),
-				MUSB_MODE(musb), devctl);
-		handled = IRQ_HANDLED;
-
-		switch (musb->xceiv->state) {
-#ifdef CONFIG_USB_MUSB_HDRC_HCD
-		case OTG_STATE_A_HOST:
-		case OTG_STATE_A_SUSPEND:
-			usb_hcd_resume_root_hub(musb_to_hcd(musb));
-			musb_root_disconnect(musb);
-			if (musb->a_wait_bcon != 0 && is_otg_enabled(musb))
-				musb_platform_try_idle(musb, jiffies
-					+ msecs_to_jiffies(musb->a_wait_bcon));
-			break;
-#endif	/* HOST */
-#ifdef CONFIG_USB_MUSB_OTG
-		case OTG_STATE_B_HOST:
-			/* REVISIT this behaves for "real disconnect"
-			 * cases; make sure the other transitions from
-			 * from B_HOST act right too.  The B_HOST code
-			 * in hnp_stop() is currently not used...
-			 */
-			musb_root_disconnect(musb);
-			musb_to_hcd(musb)->self.is_b_host = 0;
-			musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
-			MUSB_DEV_MODE(musb);
-			musb_g_disconnect(musb);
-			break;
-		case OTG_STATE_A_PERIPHERAL:
-			musb_hnp_stop(musb);
-			musb_root_disconnect(musb);
-			/* FALLTHROUGH */
-		case OTG_STATE_B_WAIT_ACON:
-			/* FALLTHROUGH */
-#endif	/* OTG */
-#ifdef CONFIG_USB_GADGET_MUSB_HDRC
-		case OTG_STATE_B_PERIPHERAL:
-		case OTG_STATE_B_IDLE:
-			musb_g_disconnect(musb);
-			break;
-#endif	/* GADGET */
-		default:
-			WARNING("unhandled DISCONNECT transition (%s)\n",
-				otg_state_string(musb));
-			break;
-		}
-
-		schedule_work(&musb->irq_work);
-	}
-
-	if (int_usb & MUSB_INTR_SUSPEND) {
-		DBG(1, "SUSPEND (%s) devctl %02x power %02x\n",
-				otg_state_string(musb), devctl, power);
-		handled = IRQ_HANDLED;
-
-		switch (musb->xceiv->state) {
-#ifdef	CONFIG_USB_MUSB_OTG
-		case OTG_STATE_A_PERIPHERAL:
-			/* We also come here if the cable is removed, since
-			 * this silicon doesn't report ID-no-longer-grounded.
-			 *
-			 * We depend on T(a_wait_bcon) to shut us down, and
-			 * hope users don't do anything dicey during this
-			 * undesired detour through A_WAIT_BCON.
-			 */
-			musb_hnp_stop(musb);
-			usb_hcd_resume_root_hub(musb_to_hcd(musb));
-			musb_root_disconnect(musb);
-			musb_platform_try_idle(musb, jiffies
-					+ msecs_to_jiffies(musb->a_wait_bcon
-						? : OTG_TIME_A_WAIT_BCON));
-			break;
-#endif
-		case OTG_STATE_B_PERIPHERAL:
-			musb_g_suspend(musb);
-			musb->is_active = is_otg_enabled(musb)
-					&& musb->xceiv->gadget->b_hnp_enable;
-			if (musb->is_active) {
-#ifdef	CONFIG_USB_MUSB_OTG
-				musb->xceiv->state = OTG_STATE_B_WAIT_ACON;
-				DBG(1, "HNP: Setting timer for b_ase0_brst\n");
-				mod_timer(&musb->otg_timer, jiffies
-					+ msecs_to_jiffies(
-							OTG_TIME_B_ASE0_BRST));
-#endif
-			}
-			break;
-		case OTG_STATE_A_WAIT_BCON:
-			if (musb->a_wait_bcon != 0)
-				musb_platform_try_idle(musb, jiffies
-					+ msecs_to_jiffies(musb->a_wait_bcon));
-			break;
-		case OTG_STATE_A_HOST:
-			musb->xceiv->state = OTG_STATE_A_SUSPEND;
-			musb->is_active = is_otg_enabled(musb)
-					&& musb->xceiv->host->b_hnp_enable;
-			break;
-		case OTG_STATE_B_HOST:
-			/* Transition to B_PERIPHERAL, see 6.8.2.6 p 44 */
-			DBG(1, "REVISIT: SUSPEND as B_HOST\n");
-			break;
-		default:
-			/* "should not happen" */
-			musb->is_active = 0;
-			break;
-		}
-		schedule_work(&musb->irq_work);
-	}
-
+	schedule_work(&musb->irq_work);
 
 	return handled;
 }
@@ -1597,11 +1579,6 @@ irqreturn_t musb_interrupt(struct musb *musb)
 		ep_num++;
 	}
 
-	/* finish handling "global" interrupts after handling fifos */
-	if (musb->int_usb)
-		retval |= musb_stage2_irq(musb,
-				musb->int_usb, devctl, power);
-
 	return retval;
 }