drivers/usbhost: Make the xHCI driver work, and support hubs.

drivers/usbhost/CMakeLists.txt

@@ -83,8 +83,12 @@ if(CONFIG_USBHOST)
     list(APPEND SRCS usbhost_bthci.c)
   endif()
 
+  if(CONFIG_USBHOST_XHCI)
+    list(APPEND SRCS usbhost_xhci.c usbhost_xhci_trace.c)
+  endif()
+
   if(CONFIG_USBHOST_XHCI_PCI)
-    list(APPEND SRCS usbhost_xhci_pci.c usbhost_xhci_trace.c)
+    list(APPEND SRCS usbhost_xhci_pci.c)
   endif()
 
   # HCD debug/trace logic

drivers/usbhost/Kconfig

@@ -778,15 +778,17 @@ config USBHOST_BTHCI
 	---help---
 		Select this option to build in support for USB Bluetooth HCI devices.
 
-menuconfig USBHOST_XHCI_PCI
-	bool "USB xHCI PCI Host Driver Support"
+config USBHOST_XHCI
+	bool
 	default n
-	depends on PCI && PCI_MSIX && USBHOST_WAITER && SCHED_HPWORK && SCHED_LPWORK
+	depends on USBHOST_WAITER && SCHED_HPWORK && SCHED_LPWORK
 	select USBHOST_HAVE_ASYNCH
 	---help---
-		USB xHCI PCI host driver support.
+		The xHCI controller driver itself, which is the same wherever the
+		controller is fitted.  Selected by whichever bus found one: PCI
+		below, or an SoC that wires one in.
 
-if USBHOST_XHCI_PCI
+if USBHOST_XHCI
 
 config USBHOST_XHCI_MAX_DEVS
 	int "xHCI maximum supported devices"
@@ -795,6 +797,30 @@ config USBHOST_XHCI_MAX_DEVS
 	---help---
 		How many USB devices will be supported by xHCI driver.
 
-endif # USBHOST_XHCI_PCI
+config USBHOST_XHCI_ENUM_RETRIES
+	int "xHCI enumeration attempts per port"
+	default 3
+	range 1 255
+	---help---
+		How many times to attempt enumeration of a newly connected device
+		before leaving the port alone until the device is unplugged.
+
+		A device whose descriptors cannot be read, or that no class driver
+		claims, fails enumeration every time.  Each failure marks the port
+		disconnected so the attempt repeats, so without a limit such a
+		device is retried for as long as it stays plugged in, logging and
+		taking a device slot on every pass.
+
+		The count is per root hub port and is cleared by a new connection.
+
+endif # USBHOST_XHCI
+
+menuconfig USBHOST_XHCI_PCI
+	bool "USB xHCI PCI Host Driver Support"
+	default n
+	depends on PCI && PCI_MSIX && USBHOST_WAITER && SCHED_HPWORK && SCHED_LPWORK
+	select USBHOST_XHCI
+	---help---
+		USB xHCI PCI host driver support.
 
 endif # USBHOST

drivers/usbhost/Make.defs

@@ -84,8 +84,12 @@ ifeq ($(CONFIG_USBHOST_BTHCI),y)
 CSRCS += usbhost_bthci.c
 endif
 
+ifeq ($(CONFIG_USBHOST_XHCI),y)
+CSRCS += usbhost_xhci.c usbhost_xhci_trace.c
+endif
+
 ifeq ($(CONFIG_USBHOST_XHCI_PCI),y)
-CSRCS += usbhost_xhci_pci.c usbhost_xhci_trace.c
+CSRCS += usbhost_xhci_pci.c
 endif
 
 # HCD debug/trace logic

drivers/usbhost/usbhost_hub.c

@@ -578,6 +578,17 @@ static inline int usbhost_hubdesc(FAR struct usbhost_class_s *hubclass)
   priv->pwrondelay  = (2 * hubdesc->pwrondelay);
   priv->ctrlcurrent = hubdesc->ctrlcurrent;
 
+  /* Publish what describes this hub as a hub, rather than as a device, on
+   * the port it occupies.  A host controller that has to be told about the
+   * hubs in a topology reads it from there when it sets up a device behind
+   * this one.  This runs before any downstream port is activated, so it is
+   * in place before there is anything behind it to set up.
+   */
+
+  hport->nports     = hubdesc->nports;
+  hport->ttt        = (hubchar & USBHUB_CHAR_TTTT_MASK) >>
+                       USBHUB_CHAR_TTTT_SHIFT;
+
   uinfo("Hub Descriptor:\n");
   uinfo("  bDescLength:         %d\n", hubdesc->len);
   uinfo("  bDescriptorType:     0x%02x\n", hubdesc->type);