3 files changed, 212 insertions, 9 deletions

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index e9426acf5682..7103758bb486 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -19,6 +19,32 @@ static inline const char *plural(int n)
         return (n == 1 ? "" : "s");
 }
 
+/* FIXME: this is a kludge */
+static int find_next_descriptor_more(unsigned char *buffer, int size,
+    int dt1, int dt2, int dt3, int *num_skipped)
+{
+        struct usb_descriptor_header *h;
+        int n = 0;
+        unsigned char *buffer0 = buffer;
+
+        /* Find the next descriptor of type dt1 or dt2 or dt3 */
+        while (size > 0) {
+                h = (struct usb_descriptor_header *) buffer;
+                if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2 ||
+                                h->bDescriptorType == dt3)
+                        break;
+                buffer += h->bLength;
+                size -= h->bLength;
+                ++n;
+        }
+
+        /* Store the number of descriptors skipped and return the
+         * number of bytes skipped */
+        if (num_skipped)
+                *num_skipped = n;
+        return buffer - buffer0;
+}
+
 static int find_next_descriptor(unsigned char *buffer, int size,
     int dt1, int dt2, int *num_skipped)
 {
@@ -43,6 +69,128 @@ static int find_next_descriptor(unsigned char *buffer, int size,
         return buffer - buffer0;
 }
 
+static int usb_parse_endpoint_companion(struct device *ddev, int cfgno,
+                int inum, int asnum, struct usb_host_endpoint *ep,
+                int num_ep, unsigned char *buffer, int size)
+{
+        unsigned char *buffer_start = buffer;
+        struct usb_ep_comp_descriptor   *desc;
+        int retval;
+        int num_skipped;
+        int max_tx;
+        int i;
+
+        /* Allocate space for the companion descriptor */
+        ep->ep_comp = kzalloc(sizeof(struct usb_host_ep_comp), GFP_KERNEL);
+        if (!ep->ep_comp)
+                return -ENOMEM;
+        desc = (struct usb_ep_comp_descriptor *) buffer;
+        if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP) {
+                dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
+                                " interface %d altsetting %d ep %d: "
+                                "using minimum values\n",
+                                cfgno, inum, asnum, ep->desc.bEndpointAddress);
+                ep->ep_comp->desc.bLength = USB_DT_EP_COMP_SIZE;
+                ep->ep_comp->desc.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
+                ep->ep_comp->desc.bMaxBurst = 0;
+                /*
+                 * Leave bmAttributes as zero, which will mean no streams for
+                 * bulk, and isoc won't support multiple bursts of packets.
+                 * With bursts of only one packet, and a Mult of 1, the max
+                 * amount of data moved per endpoint service interval is one
+                 * packet.
+                 */
+                if (usb_endpoint_xfer_isoc(&ep->desc) ||
+                                usb_endpoint_xfer_int(&ep->desc))
+                        ep->ep_comp->desc.wBytesPerInterval =
+                                ep->desc.wMaxPacketSize;
+                /*
+                 * The next descriptor is for an Endpoint or Interface,
+                 * no extra descriptors to copy into the companion structure,
+                 * and we didn't eat up any of the buffer.
+                 */
+                retval = 0;
+                goto valid;
+        }
+        memcpy(&ep->ep_comp->desc, desc, USB_DT_EP_COMP_SIZE);
+        desc = &ep->ep_comp->desc;
+        buffer += desc->bLength;
+        size -= desc->bLength;
+
+        /* Eat up the other descriptors we don't care about */
+        ep->ep_comp->extra = buffer;
+        i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
+                        USB_DT_INTERFACE, &num_skipped);
+        ep->ep_comp->extralen = i;
+        buffer += i;
+        size -= i;
+        retval = buffer - buffer_start + i;
+        if (num_skipped > 0)
+                dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
+                                num_skipped, plural(num_skipped),
+                                "SuperSpeed endpoint companion");
+
+        /* Check the various values */
+        if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
+                dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
+                                "config %d interface %d altsetting %d ep %d: "
+                                "setting to zero\n", desc->bMaxBurst,
+                                cfgno, inum, asnum, ep->desc.bEndpointAddress);
+                desc->bMaxBurst = 0;
+        }
+        if (desc->bMaxBurst > 15) {
+                dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
+                                "config %d interface %d altsetting %d ep %d: "
+                                "setting to 15\n", desc->bMaxBurst,
+                                cfgno, inum, asnum, ep->desc.bEndpointAddress);
+                desc->bMaxBurst = 15;
+        }
+        if ((usb_endpoint_xfer_control(&ep->desc) || usb_endpoint_xfer_int(&ep->desc))
+                        && desc->bmAttributes != 0) {
+                dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
+                                "config %d interface %d altsetting %d ep %d: "
+                                "setting to zero\n",
+                                usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
+                                desc->bmAttributes,
+                                cfgno, inum, asnum, ep->desc.bEndpointAddress);
+                desc->bmAttributes = 0;
+        }
+        if (usb_endpoint_xfer_bulk(&ep->desc) && desc->bmAttributes > 16) {
+                dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
+                                "config %d interface %d altsetting %d ep %d: "
+                                "setting to max\n",
+                                cfgno, inum, asnum, ep->desc.bEndpointAddress);
+                desc->bmAttributes = 16;
+        }
+        if (usb_endpoint_xfer_isoc(&ep->desc) && desc->bmAttributes > 2) {
+                dev_warn(ddev, "Isoc endpoint has Mult of %d in "
+                                "config %d interface %d altsetting %d ep %d: "
+                                "setting to 3\n", desc->bmAttributes + 1,
+                                cfgno, inum, asnum, ep->desc.bEndpointAddress);
+                desc->bmAttributes = 2;
+        }
+        if (usb_endpoint_xfer_isoc(&ep->desc)) {
+                max_tx = ep->desc.wMaxPacketSize * (desc->bMaxBurst + 1) *
+                        (desc->bmAttributes + 1);
+        } else if (usb_endpoint_xfer_int(&ep->desc)) {
+                max_tx = ep->desc.wMaxPacketSize * (desc->bMaxBurst + 1);
+        } else {
+                goto valid;
+        }
+        if (desc->wBytesPerInterval > max_tx) {
+                dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
+                                "config %d interface %d altsetting %d ep %d: "
+                                "setting to %d\n",
+                                usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
+                                desc->wBytesPerInterval,
+                                cfgno, inum, asnum, ep->desc.bEndpointAddress,
+                                max_tx);
+                desc->wBytesPerInterval = max_tx;
+        }
+valid:
+        return retval;
+}
+
 static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
     int asnum, struct usb_host_interface *ifp, int num_ep,
     unsigned char *buffer, int size)
@@ -50,7 +198,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
         unsigned char *buffer0 = buffer;
         struct usb_endpoint_descriptor *d;
         struct usb_host_endpoint *endpoint;
-        int n, i, j;
+        int n, i, j, retval;
 
         d = (struct usb_endpoint_descriptor *) buffer;
         buffer += d->bLength;
@@ -162,17 +310,38 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
                                 cfgno, inum, asnum, d->bEndpointAddress,
                                 maxp);
         }
-
-        /* Skip over any Class Specific or Vendor Specific descriptors;
-         * find the next endpoint or interface descriptor */
-        endpoint->extra = buffer;
-        i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
-            USB_DT_INTERFACE, &n);
-        endpoint->extralen = i;
+        /* Allocate room for and parse any endpoint companion descriptors */
+        if (to_usb_device(ddev)->speed == USB_SPEED_SUPER) {
+                endpoint->extra = buffer;
+                i = find_next_descriptor_more(buffer, size, USB_DT_SS_ENDPOINT_COMP,
+                                USB_DT_ENDPOINT, USB_DT_INTERFACE, &n);
+                endpoint->extralen = i;
+                buffer += i;
+                size -= i;
+
+                if (size > 0) {
+                        retval = usb_parse_endpoint_companion(ddev, cfgno, inum, asnum,
+                                        endpoint, num_ep, buffer, size);
+                        if (retval >= 0) {
+                                buffer += retval;
+                                retval = buffer - buffer0;
+                        }
+                } else {
+                        retval = buffer - buffer0;
+                }
+        } else {
+                /* Skip over any Class Specific or Vendor Specific descriptors;
+                 * find the next endpoint or interface descriptor */
+                endpoint->extra = buffer;
+                i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
+                                USB_DT_INTERFACE, &n);
+                endpoint->extralen = i;
+                retval = buffer - buffer0 + i;
+        }
         if (n > 0)
                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
                     n, plural(n), "endpoint");
-        return buffer - buffer0 + i;
+        return retval;
 
 skip_to_next_endpoint_or_interface_descriptor:
         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
@@ -453,6 +622,8 @@ static int usb_parse_configuration(struct device *ddev, int cfgidx,
                 kref_init(&intfc->ref);
         }
 
+        /* FIXME: parse the BOS descriptor */
+
         /* Skip over any Class Specific or Vendor Specific descriptors;
          * find the first interface descriptor */
         config->extra = buffer;
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 112a2d6e922f..13bced521b83 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -36,6 +36,7 @@ struct wusb_dev;
  *  - configs have one (often) or more interfaces;
  *  - interfaces have one (usually) or more settings;
  *  - each interface setting has zero or (usually) more endpoints.
+ *  - a SuperSpeed endpoint has a companion descriptor
  *
  * And there might be other descriptors mixed in with those.
  *
@@ -44,6 +45,19 @@ struct wusb_dev;
 
 struct ep_device;
 
+/* For SS devices */
+/**
+ * struct usb_host_ep_comp - Valid for SuperSpeed devices only
+ * @desc: endpoint companion descriptor, wMaxPacketSize in native byteorder
+ * @extra: descriptors following this endpoint companion descriptor
+ * @extralen: how many bytes of "extra" are valid
+ */
+struct usb_host_ep_comp {
+        struct usb_ep_comp_descriptor   desc;
+        unsigned char                   *extra;   /* Extra descriptors */
+        int                             extralen;
+};
+
 /**
  * struct usb_host_endpoint - host-side endpoint descriptor and queue
  * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder
@@ -51,6 +65,7 @@ struct ep_device;
  * @hcpriv: for use by HCD; typically holds hardware dma queue head (QH)
  *      with one or more transfer descriptors (TDs) per urb
  * @ep_dev: ep_device for sysfs info
+ * @ep_comp: companion descriptor information for this endpoint
  * @extra: descriptors following this endpoint in the configuration
  * @extralen: how many bytes of "extra" are valid
  * @enabled: URBs may be submitted to this endpoint
@@ -63,6 +78,7 @@ struct usb_host_endpoint {
         struct list_head                urb_list;
         void                            *hcpriv;
         struct ep_device                *ep_dev;        /* For sysfs info */
+        struct usb_host_ep_comp         *ep_comp;       /* For SS devices */
 
         unsigned char *extra;   /* Extra descriptors */
         int extralen;
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 93bfe6352342..9e9c5c0a3d72 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -191,6 +191,8 @@ struct usb_ctrlrequest {
 #define USB_DT_WIRE_ADAPTER             0x21
 #define USB_DT_RPIPE                    0x22
 #define USB_DT_CS_RADIO_CONTROL         0x23
+/* From the USB 3.0 spec */
+#define USB_DT_SS_ENDPOINT_COMP         0x30
 
 /* Conventional codes for class-specific descriptors.  The convention is
  * defined in the USB "Common Class" Spec (3.11).  Individual class specs
@@ -535,6 +537,20 @@ static inline int usb_endpoint_is_isoc_out(
 
 /*-------------------------------------------------------------------------*/
 
+/* USB_DT_SS_ENDPOINT_COMP: SuperSpeed Endpoint Companion descriptor */
+struct usb_ep_comp_descriptor {
+        __u8  bLength;
+        __u8  bDescriptorType;
+
+        __u8  bMaxBurst;
+        __u8  bmAttributes;
+        __u16 wBytesPerInterval;
+} __attribute__ ((packed));
+
+#define USB_DT_EP_COMP_SIZE             6
+
+/*-------------------------------------------------------------------------*/
+
 /* USB_DT_DEVICE_QUALIFIER: Device Qualifier descriptor */
 struct usb_qualifier_descriptor {
         __u8  bLength;