usb: gadget: Reset the controller when cable is unplugged

Reset the controller when the cable is unplugged to leave it in the idle
state. The OTG driver will reconfigure it on vbus/id pin detection.

Change-Id: I87903ec86f3c35af64a141f27a34cc0720a61b08
Signed-off-by: Benoit Goby <benoit@android.com>

1 files changed, 37 insertions, 21 deletions

diff --git a/drivers/usb/gadget/fsl_udc_core.c b/drivers/usb/gadget/fsl_udc_core.c
index 847ccccd068f..77b3cb7e6d9e 100644
--- a/drivers/usb/gadget/fsl_udc_core.c
+++ b/drivers/usb/gadget/fsl_udc_core.c
@@ -268,6 +268,33 @@ static void nuke(struct fsl_ep *ep, int status)
 	Internal Hardware related function
  ------------------------------------------------------------------*/
 
+#define FSL_UDC_RESET_TIMEOUT 1000
+static int dr_controller_reset(struct fsl_udc *udc)
+{
+	unsigned int tmp;
+	unsigned long timeout;
+
+	/* Stop and reset the usb controller */
+	tmp = fsl_readl(&dr_regs->usbcmd);
+	tmp &= ~USB_CMD_RUN_STOP;
+	fsl_writel(tmp, &dr_regs->usbcmd);
+
+	tmp = fsl_readl(&dr_regs->usbcmd);
+	tmp |= USB_CMD_CTRL_RESET;
+	fsl_writel(tmp, &dr_regs->usbcmd);
+
+	/* Wait for reset to complete */
+	timeout = jiffies + FSL_UDC_RESET_TIMEOUT;
+	while (fsl_readl(&dr_regs->usbcmd) & USB_CMD_CTRL_RESET) {
+		if (time_after(jiffies, timeout)) {
+			ERR("udc reset timeout!\n");
+			return -ETIMEDOUT;
+		}
+		cpu_relax();
+	}
+	return 0;
+}
+
 static int dr_controller_setup(struct fsl_udc *udc)
 {
 	unsigned int tmp, portctrl, ep_num;
@@ -275,8 +302,10 @@ static int dr_controller_setup(struct fsl_udc *udc)
 #if !defined(CONFIG_ARCH_MXC) && !defined(CONFIG_ARCH_TEGRA)
 	unsigned int ctrl;
 #endif
+#ifdef CONFIG_ARCH_TEGRA
 	unsigned long timeout;
-#define FSL_UDC_RESET_TIMEOUT 1000
+#endif
+	int status;
 
 	/* Config PHY interface */
 	portctrl = fsl_readl(&dr_regs->portsc1);
@@ -299,24 +328,9 @@ static int dr_controller_setup(struct fsl_udc *udc)
 	}
 	fsl_writel(portctrl, &dr_regs->portsc1);
 
-	/* Stop and reset the usb controller */
-	tmp = fsl_readl(&dr_regs->usbcmd);
-	tmp &= ~USB_CMD_RUN_STOP;
-	fsl_writel(tmp, &dr_regs->usbcmd);
-
-	tmp = fsl_readl(&dr_regs->usbcmd);
-	tmp |= USB_CMD_CTRL_RESET;
-	fsl_writel(tmp, &dr_regs->usbcmd);
-
-	/* Wait for reset to complete */
-	timeout = jiffies + FSL_UDC_RESET_TIMEOUT;
-	while (fsl_readl(&dr_regs->usbcmd) & USB_CMD_CTRL_RESET) {
-		if (time_after(jiffies, timeout)) {
-			ERR("udc reset timeout!\n");
-			return -ETIMEDOUT;
-		}
-		cpu_relax();
-	}
+	status = dr_controller_reset(udc);
+	if (status)
+		return status;
 
 	/* Set the controller as device mode */
 	tmp = fsl_readl(&dr_regs->usbmode);
@@ -2076,16 +2090,17 @@ static irqreturn_t fsl_udc_irq(int irq, void *_udc)
 				reset_queues(udc);
 				/* stop the controller and turn off the clocks */
 				dr_controller_stop(udc);
+				dr_controller_reset(udc);
 				fsl_udc_clk_suspend();
 				udc->vbus_active = 0;
 				udc->usb_state = USB_STATE_DEFAULT;
 			} else {
 				spin_unlock_irqrestore(&udc->lock, flags);
-				return IRQ_HANDLED;
+				return IRQ_NONE;
 			}
 		} else {
 			spin_unlock_irqrestore(&udc->lock, flags);
-			return IRQ_HANDLED;
+			return IRQ_NONE;
 		}
 	}
 #endif
@@ -2885,6 +2900,7 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
 #ifdef CONFIG_USB_OTG_UTILS
 	if (udc_controller->transceiver) {
 		dr_controller_stop(udc_controller);
+		dr_controller_reset(udc_controller);
 		fsl_udc_clk_suspend();
 		udc_controller->vbus_active = 0;
 		udc_controller->usb_state = USB_STATE_DEFAULT;