hidraw(4): Add HIDRAW_MAKE_UHID_ALIAS kernel option

which installs /dev/uhid# alias to hidraw character device for
compatibility with some existing uhid(4) users like Firefox.
As side effect it renames traditional uhid(4) driver to hidraw
to make possible using of common unit number allocator.

Requested by:	Greg V <greg_unrelenting.technology>
Reviewed by:	hselasky (as part of D27992)

sys/conf/options

@@ -1020,3 +1020,4 @@ HID_DEBUG	opt_hid.h
 IICHID_DEBUG	opt_hid.h
 IICHID_SAMPLING	opt_hid.h
 HKBD_DFLT_KEYMAP	opt_hkbd.h
+HIDRAW_MAKE_UHID_ALIAS	opt_hid.h

sys/dev/hid/hid.c

@@ -58,6 +58,10 @@ SYSCTL_NODE(_hw, OID_AUTO, hid, CTLFLAG_RW, 0, "HID debugging");
 SYSCTL_INT(_hw_hid, OID_AUTO, debug, CTLFLAG_RWTUN,
     &hid_debug, 0, "Debug level");
 
+#ifdef HIDRAW_MAKE_UHID_ALIAS
+devclass_t hidraw_devclass;
+#endif
+
 static void hid_clear_local(struct hid_item *);
 static uint8_t hid_get_byte(struct hid_data *s, const uint16_t wSize);
 

sys/dev/hid/hid.h

@@ -193,6 +193,9 @@
 #define	HID_MAX_AUTO_QUIRK	8	/* maximum number of dynamic quirks */
 #define	HID_PNP_ID_SIZE		20	/* includes null terminator */
 
+/* Share unit number pool between uhid and hidraw */
+extern devclass_t hidraw_devclass;
+
 /* Declare global HID debug variable. */
 extern int hid_debug;
 

sys/dev/hid/hidraw.c

@@ -38,6 +38,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "opt_hid.h"
+
 #include <sys/param.h>
 #include <sys/bus.h>
 #include <sys/conf.h>
@@ -207,6 +209,9 @@ hidraw_attach(device_t self)
 		hidraw_detach(self);
 		return (error);
 	}
+#ifdef HIDRAW_MAKE_UHID_ALIAS
+	(void)make_dev_alias(sc->dev, "uhid%d", device_get_unit(self));
+#endif
 
 	hidbus_set_lock(self, &sc->sc_mtx);
 	hidbus_set_intr(self, hidraw_intr, sc);
@@ -893,7 +898,9 @@ static driver_t hidraw_driver = {
 	sizeof(struct hidraw_softc)
 };
 
-static devclass_t hidraw_devclass;
+#ifndef HIDRAW_MAKE_UHID_ALIAS
+devclass_t hidraw_devclass;
+#endif
 
 DRIVER_MODULE(hidraw, hidbus, hidraw_driver, hidraw_devclass, NULL, 0);
 MODULE_DEPEND(hidraw, hidbus, 1, 1, 1);

sys/dev/usb/input/uhid.c

@@ -43,6 +43,8 @@ __FBSDID("$FreeBSD$");
  * HID spec: http://www.usb.org/developers/devclass_docs/HID1_11.pdf
  */
 
+#include "opt_hid.h"
+
 #include <sys/stdint.h>
 #include <sys/stddef.h>
 #include <sys/param.h>
@@ -891,7 +893,9 @@ uhid_detach(device_t dev)
 	return (0);
 }
 
+#ifndef HIDRAW_MAKE_UHID_ALIAS
 static devclass_t uhid_devclass;
+#endif
 
 static device_method_t uhid_methods[] = {
 	DEVMETHOD(device_probe, uhid_probe),
@@ -902,12 +906,20 @@ static device_method_t uhid_methods[] = {
 };
 
 static driver_t uhid_driver = {
+#ifdef HIDRAW_MAKE_UHID_ALIAS
+	.name = "hidraw",
+#else
 	.name = "uhid",
+#endif
 	.methods = uhid_methods,
 	.size = sizeof(struct uhid_softc),
 };
 
+#ifdef HIDRAW_MAKE_UHID_ALIAS
+DRIVER_MODULE(uhid, uhub, uhid_driver, hidraw_devclass, NULL, 0);
+#else
 DRIVER_MODULE(uhid, uhub, uhid_driver, uhid_devclass, NULL, 0);
+#endif
 MODULE_DEPEND(uhid, usb, 1, 1, 1);
 MODULE_DEPEND(uhid, hid, 1, 1, 1);
 MODULE_VERSION(uhid, 1);

sys/modules/hid/hidraw/Makefile

@@ -4,6 +4,6 @@
 
 KMOD=	hidraw
 SRCS=	hidraw.c
-SRCS+=	bus_if.h device_if.h
+SRCS+=	opt_hid.h bus_if.h device_if.h
 
 .include <bsd.kmod.mk>

sys/modules/usb/uhid/Makefile

@@ -30,7 +30,7 @@ S=     ${SRCTOP}/sys
 .PATH: $S/dev/usb/input
 
 KMOD=	uhid
-SRCS=	opt_bus.h opt_usb.h device_if.h bus_if.h usb_if.h vnode_if.h usbdevs.h \
-	uhid.c
+SRCS=	opt_bus.h opt_hid.h opt_usb.h device_if.h bus_if.h usb_if.h \
+	vnode_if.h usbdevs.h uhid.c
 
 .include <bsd.kmod.mk>