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-rw-r--r--drivers/usb/gadget/composite.c24
1 files changed, 18 insertions, 6 deletions
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index cd303a3ea680..223f72d4d9ed 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -438,9 +438,13 @@ static u8 encode_bMaxPower(enum usb_device_speed speed,
 	if (!val)
 		return 0;
 	if (speed < USB_SPEED_SUPER)
-		return DIV_ROUND_UP(val, 2);
+		return min(val, 500U) / 2;
 	else
-		return DIV_ROUND_UP(val, 8);
+		/*
+		 * USB 3.x supports up to 900mA, but since 900 isn't divisible
+		 * by 8 the integral division will effectively cap to 896mA.
+		 */
+		return min(val, 900U) / 8;
 }
 
 static int config_buf(struct usb_configuration *config,
@@ -852,6 +856,10 @@ static int set_config(struct usb_composite_dev *cdev,
 
 	/* when we return, be sure our power usage is valid */
 	power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
+	if (gadget->speed < USB_SPEED_SUPER)
+		power = min(power, 500U);
+	else
+		power = min(power, 900U);
 done:
 	usb_gadget_vbus_draw(gadget, power);
 	if (result >= 0 && cdev->delayed_status)
@@ -2278,7 +2286,7 @@ void composite_resume(struct usb_gadget *gadget)
 {
 	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
 	struct usb_function		*f;
-	u16				maxpower;
+	unsigned			maxpower;
 
 	/* REVISIT:  should we have config level
 	 * suspend/resume callbacks?
@@ -2292,10 +2300,14 @@ void composite_resume(struct usb_gadget *gadget)
 				f->resume(f);
 		}
 
-		maxpower = cdev->config->MaxPower;
+		maxpower = cdev->config->MaxPower ?
+			cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
+		if (gadget->speed < USB_SPEED_SUPER)
+			maxpower = min(maxpower, 500U);
+		else
+			maxpower = min(maxpower, 900U);
 
-		usb_gadget_vbus_draw(gadget, maxpower ?
-			maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
+		usb_gadget_vbus_draw(gadget, maxpower);
 	}
 
 	cdev->suspended = 0;