1 files changed, 28 insertions, 75 deletions

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 94a14f5dc4d4..71912301ef7f 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -946,7 +946,7 @@ static int wait_serial_change(struct acm *acm, unsigned long arg)
 	DECLARE_WAITQUEUE(wait, current);
 	struct async_icount old, new;
 
-	if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD ))
+	if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD))
 		return -EINVAL;
 	do {
 		spin_lock_irq(&acm->read_lock);
@@ -1146,7 +1146,7 @@ static int acm_probe(struct usb_interface *intf,
 		     const struct usb_device_id *id)
 {
 	struct usb_cdc_union_desc *union_header = NULL;
-	struct usb_cdc_country_functional_desc *cfd = NULL;
+	struct usb_cdc_call_mgmt_descriptor *cmgmd = NULL;
 	unsigned char *buffer = intf->altsetting->extra;
 	int buflen = intf->altsetting->extralen;
 	struct usb_interface *control_interface;
@@ -1155,18 +1155,16 @@ static int acm_probe(struct usb_interface *intf,
 	struct usb_endpoint_descriptor *epread = NULL;
 	struct usb_endpoint_descriptor *epwrite = NULL;
 	struct usb_device *usb_dev = interface_to_usbdev(intf);
+	struct usb_cdc_parsed_header h;
 	struct acm *acm;
 	int minor;
 	int ctrlsize, readsize;
 	u8 *buf;
-	u8 ac_management_function = 0;
-	u8 call_management_function = 0;
-	int call_interface_num = -1;
-	int data_interface_num = -1;
+	int call_intf_num = -1;
+	int data_intf_num = -1;
 	unsigned long quirks;
 	int num_rx_buf;
 	int i;
-	unsigned int elength = 0;
 	int combined_interfaces = 0;
 	struct device *tty_dev;
 	int rv = -ENOMEM;
@@ -1210,70 +1208,22 @@ static int acm_probe(struct usb_interface *intf,
 		}
 	}
 
-	while (buflen > 0) {
-		elength = buffer[0];
-		if (!elength) {
-			dev_err(&intf->dev, "skipping garbage byte\n");
-			elength = 1;
-			goto next_desc;
-		}
-		if (buffer[1] != USB_DT_CS_INTERFACE) {
-			dev_err(&intf->dev, "skipping garbage\n");
-			goto next_desc;
-		}
-
-		switch (buffer[2]) {
-		case USB_CDC_UNION_TYPE: /* we've found it */
-			if (elength < sizeof(struct usb_cdc_union_desc))
-				goto next_desc;
-			if (union_header) {
-				dev_err(&intf->dev, "More than one "
-					"union descriptor, skipping ...\n");
-				goto next_desc;
-			}
-			union_header = (struct usb_cdc_union_desc *)buffer;
-			break;
-		case USB_CDC_COUNTRY_TYPE: /* export through sysfs*/
-			if (elength < sizeof(struct usb_cdc_country_functional_desc))
-				goto next_desc;
-			cfd = (struct usb_cdc_country_functional_desc *)buffer;
-			break;
-		case USB_CDC_HEADER_TYPE: /* maybe check version */
-			break; /* for now we ignore it */
-		case USB_CDC_ACM_TYPE:
-			if (elength < 4)
-				goto next_desc;
-			ac_management_function = buffer[3];
-			break;
-		case USB_CDC_CALL_MANAGEMENT_TYPE:
-			if (elength < 5)
-				goto next_desc;
-			call_management_function = buffer[3];
-			call_interface_num = buffer[4];
-			break;
-		default:
-			/*
-			 * there are LOTS more CDC descriptors that
-			 * could legitimately be found here.
-			 */
-			dev_dbg(&intf->dev, "Ignoring descriptor: "
-					"type %02x, length %ud\n",
-					buffer[2], elength);
-			break;
-		}
-next_desc:
-		buflen -= elength;
-		buffer += elength;
-	}
+	cdc_parse_cdc_header(&h, intf, buffer, buflen);
+	union_header = h.usb_cdc_union_desc;
+	cmgmd = h.usb_cdc_call_mgmt_descriptor;
+	if (cmgmd)
+		call_intf_num = cmgmd->bDataInterface;
 
 	if (!union_header) {
-		if (call_interface_num > 0) {
+		if (call_intf_num > 0) {
 			dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n");
 			/* quirks for Droids MuIn LCD */
-			if (quirks & NO_DATA_INTERFACE)
+			if (quirks & NO_DATA_INTERFACE) {
 				data_interface = usb_ifnum_to_if(usb_dev, 0);
-			else
-				data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
+			} else {
+				data_intf_num = call_intf_num;
+				data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
+			}
 			control_interface = intf;
 		} else {
 			if (intf->cur_altsetting->desc.bNumEndpoints != 3) {
@@ -1287,8 +1237,9 @@ next_desc:
 			}
 		}
 	} else {
+		data_intf_num = union_header->bSlaveInterface0;
 		control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
-		data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = union_header->bSlaveInterface0));
+		data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
 	}
 
 	if (!control_interface || !data_interface) {
@@ -1296,7 +1247,7 @@ next_desc:
 		return -ENODEV;
 	}
 
-	if (data_interface_num != call_interface_num)
+	if (data_intf_num != call_intf_num)
 		dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");
 
 	if (control_interface == data_interface) {
@@ -1379,11 +1330,8 @@ made_compressed_probe:
 		goto alloc_fail;
 
 	minor = acm_alloc_minor(acm);
-	if (minor < 0) {
-		dev_err(&intf->dev, "no more free acm devices\n");
-		kfree(acm);
-		return -ENODEV;
-	}
+	if (minor < 0)
+		goto alloc_fail1;
 
 	ctrlsize = usb_endpoint_maxp(epctrl);
 	readsize = usb_endpoint_maxp(epread) *
@@ -1394,7 +1342,8 @@ made_compressed_probe:
 	acm->data = data_interface;
 	acm->minor = minor;
 	acm->dev = usb_dev;
-	acm->ctrl_caps = ac_management_function;
+	if (h.usb_cdc_acm_descriptor)
+		acm->ctrl_caps = h.usb_cdc_acm_descriptor->bmCapabilities;
 	if (quirks & NO_CAP_LINE)
 		acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
 	acm->ctrlsize = ctrlsize;
@@ -1488,7 +1437,10 @@ made_compressed_probe:
 	if (i < 0)
 		goto alloc_fail7;
 
-	if (cfd) { /* export the country data */
+	if (h.usb_cdc_country_functional_desc) { /* export the country data */
+		struct usb_cdc_country_functional_desc * cfd =
+					h.usb_cdc_country_functional_desc;
+
 		acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
 		if (!acm->country_codes)
 			goto skip_countries;
@@ -1572,6 +1524,7 @@ alloc_fail4:
 	usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
 alloc_fail2:
 	acm_release_minor(acm);
+alloc_fail1:
 	kfree(acm);
 alloc_fail:
 	return rv;