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 <[e-mail]>
Tested-by: Jenya Y <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/core/generic.c

···
 		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

···
 	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 {
···
 		/* 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);
···
 
 	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;
···
 		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) {
···
 			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;
···
 	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;
 		}
 	}
···
 		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);
···
 				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;
 			}
···
 				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) {
···
 
 		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)
···
   
 	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;
···
 				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;
···
 	else
 		unit_load = 100;
 
+	status = 0;
 	for (i = 0; i < SET_CONFIG_TRIES; i++) {
 
 		/* reallocate for each attempt, since references
···
 	}
 	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);