Changeset 375211d2 in mainline

Timestamp:

2017-11-20T22:15:11Z (7 years ago)

Author:

Aearsis <Hlavaty.Ondrej@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

6d91888

Parents:

9162b27

git-author:

Aearsis <Hlavaty.Ondrej@…> (2017-11-20 22:13:54)

git-committer:

Aearsis <Hlavaty.Ondrej@…> (2017-11-20 22:15:11)

Message:

usbhost: updated determining MPS for USB 3

USB 3 changes the meaning of the max packet size in device descriptor.

File:

• uspace/lib/usbhost/src/hcd.c (modified) (3 diffs)

uspace/lib/usbhost/src/hcd.c

@@ -67 +67 @@
  * the first 8B of the device descriptor to determine it.
  *
- * @return Combined value of max_packet_size and scheduling oppertunities,
- *      see usb_standard_device_descriptor_t.
+ * @return Max packet size for EP 0
  */
 int hcd_get_ep0_max_packet_size(uint16_t *mps, hcd_t *hcd, device_t *dev)
 {
+        assert(mps);
+
         static const uint16_t mps_fixed [] = {
                 [USB_SPEED_LOW] = 8,
@@ -92 +93 @@
             GET_DEVICE_DESC(CTRL_PIPE_MIN_PACKET_SIZE);
 
-        usb_log_debug("Requesting first 8B of device descriptor.");
+        usb_log_debug("Requesting first 8B of device descriptor to determine MPS.");
         ssize_t got = hcd_send_batch_sync(hcd, dev, control_ep, USB_DIRECTION_IN,
             (char *) &desc, CTRL_PIPE_MIN_PACKET_SIZE, *(uint64_t *)&get_device_desc_8,
@@ -103 +104 @@
         }
 
-        *mps = uint16_usb2host(desc.max_packet_size);
+        if (desc.descriptor_type != USB_DESCTYPE_DEVICE) {
+                usb_log_error("The device responded with wrong device descriptor.");
+                return EIO;
+        }
+
+        uint16_t version = uint16_usb2host(desc.usb_spec_version);
+        if (version < 0x0300) {
+                /* USB 2 and below have MPS raw in the field */
+                *mps = desc.max_packet_size;
+        } else {
+                /* USB 3 have MPS as an 2-based exponent */
+                *mps = (1 << desc.max_packet_size);
+        }
         return EOK;
 }