Add support for disabling USB enumeration in general or on selected

USB HUBs.

MFC after:	2 weeks

4 files changed, 39 insertions, 1 deletions

diff --git a/sys/dev/usb/controller/usb_controller.c b/sys/dev/usb/controller/usb_controller.c
index dc10591..1d202dd 100644
--- a/sys/dev/usb/controller/usb_controller.c
+++ b/sys/dev/usb/controller/usb_controller.c
@@ -102,6 +102,14 @@ static int usb_no_shutdown_wait = 0;
 SYSCTL_INT(_hw_usb, OID_AUTO, no_shutdown_wait, CTLFLAG_RWTUN,
     &usb_no_shutdown_wait, 0, "No USB device waiting at system shutdown.");
 
+#if USB_HAVE_DISABLE_ENUM
+static int usb_disable_enumeration = 0;
+SYSCTL_INT(_hw_usb, OID_AUTO, disable_enumeration, CTLFLAG_RWTUN,
+    &usb_disable_enumeration, 0, "Set to disable all USB device enumeration.");
+#else
+#define	usb_disable_enumeration 0
+#endif
+
 static devclass_t usb_devclass;
 
 static device_method_t usb_methods[] = {
@@ -371,7 +379,8 @@ usb_bus_explore(struct usb_proc_msg *pm)
 		USB_BUS_LOCK(bus);
 	}
 
-	if (udev != NULL && udev->hub != NULL) {
+	if (usb_disable_enumeration == 0 &&
+	    udev != NULL && udev->hub != NULL) {
 
 		if (bus->do_probe) {
 			bus->do_probe = 0;
diff --git a/sys/dev/usb/usb_freebsd.h b/sys/dev/usb/usb_freebsd.h
index cda4e69..5c10923 100644
--- a/sys/dev/usb/usb_freebsd.h
+++ b/sys/dev/usb/usb_freebsd.h
@@ -50,6 +50,7 @@
 #define	USB_HAVE_FIXED_IFACE 0
 #define	USB_HAVE_FIXED_CONFIG 0
 #define	USB_HAVE_FIXED_PORT 0
+#define	USB_HAVE_DISABLE_ENUM 1
 
 /* define zero ticks callout value */
 #define	USB_CALLOUT_ZERO_TICKS 1
diff --git a/sys/dev/usb/usb_freebsd_loader.h b/sys/dev/usb/usb_freebsd_loader.h
index bd08218..4f82dd0 100644
--- a/sys/dev/usb/usb_freebsd_loader.h
+++ b/sys/dev/usb/usb_freebsd_loader.h
@@ -50,6 +50,7 @@
 #define	USB_HAVE_FIXED_IFACE 0
 #define	USB_HAVE_FIXED_CONFIG 0
 #define	USB_HAVE_FIXED_PORT 0
+#define	USB_HAVE_DISABLE_ENUM 0
 
 #define	USB_CALLOUT_ZERO_TICKS 1
 
diff --git a/sys/dev/usb/usb_hub.c b/sys/dev/usb/usb_hub.c
index 8e0d557..3385d9a 100644
--- a/sys/dev/usb/usb_hub.c
+++ b/sys/dev/usb/usb_hub.c
@@ -111,6 +111,9 @@ struct uhub_softc {
 	struct mtx sc_mtx;		/* our mutex */
 	struct usb_device *sc_udev;	/* USB device */
 	struct usb_xfer *sc_xfer[UHUB_N_TRANSFER];	/* interrupt xfer */
+#if USB_HAVE_DISABLE_ENUM
+	int sc_disable_enumeration;
+#endif
 	uint8_t	sc_flags;
 #define	UHUB_FLAG_DID_EXPLORE 0x01
 };
@@ -993,6 +996,13 @@ uhub_explore(struct usb_device *udev)
 
 	DPRINTFN(11, "udev=%p addr=%d\n", udev, udev->address);
 
+#if USB_HAVE_DISABLE_ENUM
+	/* check if we should skip enumeration from this USB HUB */
+	if (sc->sc_disable_enumeration != 0) {
+		DPRINTF("Enumeration is disabled!\n");
+		return (0);
+	}
+#endif
 	/* ignore devices that are too deep */
 	if (uhub_is_too_deep(udev))
 		return (USB_ERR_TOO_DEEP);
@@ -1188,6 +1198,10 @@ uhub_attach(device_t dev)
 	struct usb_hub *hub;
 	struct usb_hub_descriptor hubdesc20;
 	struct usb_hub_ss_descriptor hubdesc30;
+#if USB_HAVE_DISABLE_ENUM
+	struct sysctl_ctx_list *sysctl_ctx;
+	struct sysctl_oid *sysctl_tree;
+#endif
 	uint16_t pwrdly;
 	uint16_t nports;
 	uint8_t x;
@@ -1469,6 +1483,19 @@ uhub_attach(device_t dev)
 
 	usbd_set_power_mode(udev, USB_POWER_MODE_SAVE);
 
+#if USB_HAVE_DISABLE_ENUM
+	/* Add device sysctls */
+
+	sysctl_ctx = device_get_sysctl_ctx(dev);
+	sysctl_tree = device_get_sysctl_tree(dev);
+
+	if (sysctl_ctx != NULL && sysctl_tree != NULL) {
+		(void) SYSCTL_ADD_INT(sysctl_ctx, SYSCTL_CHILDREN(sysctl_tree),
+		    OID_AUTO, "disable_enumeration", CTLFLAG_RWTUN,
+		    &sc->sc_disable_enumeration, 0,
+		    "Set to disable enumeration on this USB HUB.");
+	}
+#endif
 	return (0);
 
 error: