__u8 index,
                  const char *buffer, int len)
 {
+       int ret;
+
        memcpy(gspca_dev->usb_buf, buffer, len);
-       usb_control_msg(gspca_dev->dev,
+       ret = usb_control_msg(gspca_dev->dev,
                        usb_sndctrlpipe(gspca_dev->dev, 0),
                        1,              /* request */
                        USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                        0,              /* value */
                        index, gspca_dev->usb_buf, len,
                        500);
+       if (ret < 0)
+               PDEBUG(D_ERR, "reg_w_buf(): "
+               "Failed to write registers to index 0x%x, error %i",
+               index, ret);
 }
 
 
                  __u8 index,
                  __u8 value)
 {
+       int ret;
+
        gspca_dev->usb_buf[0] = value;
-       usb_control_msg(gspca_dev->dev,
+       ret = usb_control_msg(gspca_dev->dev,
                        usb_sndctrlpipe(gspca_dev->dev, 0),
                        0,                      /* request */
                        USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                        0, index, gspca_dev->usb_buf, 1,
                        500);
+       if (ret < 0)
+               PDEBUG(D_ERR, "reg_w(): "
+               "Failed to write register to index 0x%x, value 0x%x, error %i",
+               index, value, ret);
 }
 
 static void reg_w_seq(struct gspca_dev *gspca_dev,
                        const __u8 *page, int len)
 {
        int index;
+       int ret;
 
        for (index = 0; index < len; index++) {
                if (page[index] == SKIP)                /* skip this index */
                        continue;
                gspca_dev->usb_buf[0] = page[index];
-               usb_control_msg(gspca_dev->dev,
+               ret = usb_control_msg(gspca_dev->dev,
                                usb_sndctrlpipe(gspca_dev->dev, 0),
                                0,                      /* request */
                        USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                0, index, gspca_dev->usb_buf, 1,
                                500);
+               if (ret < 0)
+                       PDEBUG(D_ERR, "reg_w_page(): "
+                       "Failed to write register to index 0x%x, "
+                       "value 0x%x, error %i",
+                       index, page[index], ret);
        }
 }
 
 
                  __u8 index,
                  const char *buffer, int len)
 {
+       int ret;
+
        memcpy(gspca_dev->usb_buf, buffer, len);
-       usb_control_msg(gspca_dev->dev,
+       ret = usb_control_msg(gspca_dev->dev,
                        usb_sndctrlpipe(gspca_dev->dev, 0),
                        1,              /* request */
                        USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                        0,              /* value */
                        index, gspca_dev->usb_buf, len,
                        500);
+       if (ret < 0)
+               PDEBUG(D_ERR, "reg_w_buf(): "
+               "Failed to write registers to index 0x%x, error %i",
+               index, ret);
 }
 
 
                  __u8 index,
                  __u8 value)
 {
+       int ret;
+
        gspca_dev->usb_buf[0] = value;
-       usb_control_msg(gspca_dev->dev,
+       ret = usb_control_msg(gspca_dev->dev,
                        usb_sndctrlpipe(gspca_dev->dev, 0),
                        0,                      /* request */
                        USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                        0, index, gspca_dev->usb_buf, 1,
                        500);
+       if (ret < 0)
+               PDEBUG(D_ERR, "reg_w(): "
+               "Failed to write register to index 0x%x, value 0x%x, error %i",
+               index, value, ret);
 }
 
 static void reg_w_seq(struct gspca_dev *gspca_dev,
                        const __u8 *page, int len)
 {
        int index;
+       int ret;
 
        for (index = 0; index < len; index++) {
                if (page[index] == SKIP)                /* skip this index */
                        continue;
                gspca_dev->usb_buf[0] = page[index];
-               usb_control_msg(gspca_dev->dev,
+               ret = usb_control_msg(gspca_dev->dev,
                                usb_sndctrlpipe(gspca_dev->dev, 0),
                                0,                      /* request */
                        USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                0, index, gspca_dev->usb_buf, 1,
                                500);
+               if (ret < 0)
+                       PDEBUG(D_ERR, "reg_w_page(): "
+                       "Failed to write register to index 0x%x, "
+                       "value 0x%x, error %i",
+                       index, page[index], ret);
        }
 }