cdc-wdm: use the common CDC parser

Now that the common parser resides in USB core, it can
be used for CDC-WDM.

Signed-off-by: Oliver Neukum <ONeukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 5 insertions, 25 deletions

diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index 61ea87917433..337948c42110 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -875,38 +875,18 @@ static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
         int rv = -EINVAL;
         struct usb_host_interface *iface;
         struct usb_endpoint_descriptor *ep;
-        struct usb_cdc_dmm_desc *dmhd;
+        struct usb_cdc_parsed_header hdr;
         u8 *buffer = intf->altsetting->extra;
         int buflen = intf->altsetting->extralen;
         u16 maxcom = WDM_DEFAULT_BUFSIZE;
 
         if (!buffer)
                 goto err;
-        while (buflen > 2) {
-                if (buffer[1] != USB_DT_CS_INTERFACE) {
-                        dev_err(&intf->dev, "skipping garbage\n");
-                        goto next_desc;
-                }
 
-                switch (buffer[2]) {
-                case USB_CDC_HEADER_TYPE:
-                        break;
-                case USB_CDC_DMM_TYPE:
-                        dmhd = (struct usb_cdc_dmm_desc *)buffer;
-                        maxcom = le16_to_cpu(dmhd->wMaxCommand);
-                        dev_dbg(&intf->dev,
-                                "Finding maximum buffer length: %d", maxcom);
-                        break;
-                default:
-                        dev_err(&intf->dev,
-                                "Ignoring extra header, type %d, length %d\n",
-                                buffer[2], buffer[0]);
-                        break;
-                }
-next_desc:
-                buflen -= buffer[0];
-                buffer += buffer[0];
-        }
+        cdc_parse_cdc_header(&hdr, intf, buffer, buflen);
+
+        if (hdr.usb_cdc_dmm_desc)
+                maxcom = le16_to_cpu(hdr.usb_cdc_dmm_desc->wMaxCommand);
 
         iface = intf->cur_altsetting;
         if (iface->desc.bNumEndpoints != 1)