USB: avoid error messages when a device is disconnected

This patch (as1673) reduces the amount of log spew from the hub driver
by removing a bunch of error messages in the case where the device in
question is already known to have been disconnected.  Since the
disconnect event itself appears in the log, there's no need for other
error messages.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Jenya Y <jy.gerstmaier@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/generic.c

@@ -169,7 +169,7 @@ static int generic_probe(struct usb_device *udev)
 		c = usb_choose_configuration(udev);
 		if (c >= 0) {
 			err = usb_set_configuration(udev, c);
-			if (err) {
+			if (err && err != -ENODEV) {
 				dev_err(&udev->dev, "can't set config #%d, error %d\n",
 					c, err);
 				/* This need not be fatal.  The user can try to

drivers/usb/core/hub.c

@@ -555,8 +555,9 @@ static int hub_port_status(struct usb_hub *hub, int port1,
 	mutex_lock(&hub->status_mutex);
 	ret = get_port_status(hub->hdev, port1, &hub->status->port);
 	if (ret < 4) {
-		dev_err(hub->intfdev,
-			"%s failed (err = %d)\n", __func__, ret);
+		if (ret != -ENODEV)
+			dev_err(hub->intfdev,
+				"%s failed (err = %d)\n", __func__, ret);
 		if (ret >= 0)
 			ret = -EIO;
 	} else {
@@ -699,7 +700,7 @@ static void hub_tt_work(struct work_struct *work)
 		/* drop lock so HCD can concurrently report other TT errors */
 		spin_unlock_irqrestore (&hub->tt.lock, flags);
 		status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
-		if (status)
+		if (status && status != -ENODEV)
 			dev_err (&hdev->dev,
 				"clear tt %d (%04x) error %d\n",
 				clear->tt, clear->devinfo, status);
@@ -837,10 +838,11 @@ static int hub_hub_status(struct usb_hub *hub,
 
 	mutex_lock(&hub->status_mutex);
 	ret = get_hub_status(hub->hdev, &hub->status->hub);
-	if (ret < 0)
-		dev_err (hub->intfdev,
-			"%s failed (err = %d)\n", __func__, ret);
-	else {
+	if (ret < 0) {
+		if (ret != -ENODEV)
+			dev_err(hub->intfdev,
+				"%s failed (err = %d)\n", __func__, ret);
+	} else {
 		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 		*change = le16_to_cpu(hub->status->hub.wHubChange); 
 		ret = 0;
@@ -877,11 +879,8 @@ static int hub_usb3_port_disable(struct usb_hub *hub, int port1)
 		return -EINVAL;
 
 	ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED);
-	if (ret) {
-		dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
-				port1, ret);
+	if (ret)
 		return ret;
-	}
 
 	/* Wait for the link to enter the disabled state. */
 	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
@@ -918,7 +917,7 @@ static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 			ret = usb_clear_port_feature(hdev, port1,
 					USB_PORT_FEAT_ENABLE);
 	}
-	if (ret)
+	if (ret && ret != -ENODEV)
 		dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 				port1, ret);
 	return ret;
@@ -2196,8 +2195,9 @@ static int usb_enumerate_device(struct usb_device *udev)
 	if (udev->config == NULL) {
 		err = usb_get_configuration(udev);
 		if (err < 0) {
-			dev_err(&udev->dev, "can't read configurations, error %d\n",
-				err);
+			if (err != -ENODEV)
+				dev_err(&udev->dev, "can't read configurations, error %d\n",
+						err);
 			return err;
 		}
 	}
@@ -2644,14 +2644,16 @@ static int hub_port_reset(struct usb_hub *hub, int port1,
 		status = set_port_feature(hub->hdev, port1, (warm ?
 					USB_PORT_FEAT_BH_PORT_RESET :
 					USB_PORT_FEAT_RESET));
-		if (status) {
+		if (status == -ENODEV) {
+			;	/* The hub is gone */
+		} else if (status) {
 			dev_err(hub->intfdev,
 					"cannot %sreset port %d (err = %d)\n",
 					warm ? "warm " : "", port1, status);
 		} else {
 			status = hub_port_wait_reset(hub, port1, udev, delay,
 								warm);
-			if (status && status != -ENOTCONN)
+			if (status && status != -ENOTCONN && status != -ENODEV)
 				dev_dbg(hub->intfdev,
 						"port_wait_reset: err = %d\n",
 						status);
@@ -4094,9 +4096,9 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
 				goto fail;
 			}
 			if (r) {
-				dev_err(&udev->dev,
-					"device descriptor read/64, error %d\n",
-					r);
+				if (r != -ENODEV)
+					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
+							r);
 				retval = -EMSGSIZE;
 				continue;
 			}
@@ -4116,9 +4118,9 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
 				msleep(200);
 			}
 			if (retval < 0) {
-				dev_err(&udev->dev,
-					"device not accepting address %d, error %d\n",
-					devnum, retval);
+				if (retval != -ENODEV)
+					dev_err(&udev->dev, "device not accepting address %d, error %d\n",
+							devnum, retval);
 				goto fail;
 			}
 			if (udev->speed == USB_SPEED_SUPER) {
@@ -4140,7 +4142,8 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
 
 		retval = usb_get_device_descriptor(udev, 8);
 		if (retval < 8) {
-			dev_err(&udev->dev,
+			if (retval != -ENODEV)
+				dev_err(&udev->dev,
 					"device descriptor read/8, error %d\n",
 					retval);
 			if (retval >= 0)
@@ -4194,8 +4197,9 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
   
 	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
 	if (retval < (signed)sizeof(udev->descriptor)) {
-		dev_err(&udev->dev, "device descriptor read/all, error %d\n",
-			retval);
+		if (retval != -ENODEV)
+			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
+					retval);
 		if (retval >= 0)
 			retval = -ENOMSG;
 		goto fail;
@@ -4377,7 +4381,7 @@ static void hub_port_connect_change(struct usb_hub *hub, int port1,
 				USB_PORT_STAT_C_ENABLE)) {
 		status = hub_port_debounce_be_stable(hub, port1);
 		if (status < 0) {
-			if (printk_ratelimit())
+			if (status != -ENODEV && printk_ratelimit())
 				dev_err(hub_dev, "connect-debounce failed, "
 						"port %d disabled\n", port1);
 			portstatus &= ~USB_PORT_STAT_CONNECTION;
@@ -4406,6 +4410,7 @@ static void hub_port_connect_change(struct usb_hub *hub, int port1,
 	else
 		unit_load = 100;
 
+	status = 0;
 	for (i = 0; i < SET_CONFIG_TRIES; i++) {
 
 		/* reallocate for each attempt, since references
@@ -4530,9 +4535,11 @@ static void hub_port_connect_change(struct usb_hub *hub, int port1,
 	}
 	if (hub->hdev->parent ||
 			!hcd->driver->port_handed_over ||
-			!(hcd->driver->port_handed_over)(hcd, port1))
-		dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
-				port1);
+			!(hcd->driver->port_handed_over)(hcd, port1)) {
+		if (status != -ENOTCONN && status != -ENODEV)
+			dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
+					port1);
+	}
  
 done:
 	hub_port_disable(hub, port1, 1);