xref: /freebsd-13-stable/sys/mips/mediatek/palmbus.c (revision 3bc80996974a61a4223eae4c1ccd47b6ee32a48a)
1 /*-
2  * Copyright (c) 2016 Stanislav Galabov.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/module.h>
31 #include <sys/bus.h>
32 #include <sys/conf.h>
33 #include <sys/kernel.h>
34 #include <sys/rman.h>
35 
36 #include <dev/ofw/openfirm.h>
37 #include <dev/ofw/ofw_bus.h>
38 #include <dev/ofw/ofw_bus_subr.h>
39 
40 #include <dev/fdt/simplebus.h>
41 
42 /*
43  * Driver for Mediatek/Ralink Palmbus
44  *
45  * Currently the only reason for the existence of this driver is so that we can
46  * minimize the changes required to the upstream DTS files we use.
47  * Otherwise palmbus is a very simple subclass of our simplebus and the only
48  * difference between the two is the actual value of the compatible property.
49  */
50 
51 static int
palmbus_probe(device_t dev)52 palmbus_probe(device_t dev)
53 {
54 
55 	if (!ofw_bus_status_okay(dev))
56 		return (ENXIO);
57 
58 	if (!(ofw_bus_is_compatible(dev, "palmbus") &&
59 	    ofw_bus_has_prop(dev, "ranges")) &&
60 	    (ofw_bus_get_type(dev) == NULL || strcmp(ofw_bus_get_type(dev),
61 	    "soc") != 0))
62 		return (ENXIO);
63 
64 	device_set_desc(dev, "MTK Palmbus");
65 
66 	return (0);
67 }
68 
69 static device_method_t palmbus_methods[] = {
70 	DEVMETHOD(device_probe,		palmbus_probe),
71 
72 	DEVMETHOD_END
73 };
74 
75 DEFINE_CLASS_1(palmbus, palmbus_driver, palmbus_methods,
76     sizeof(struct simplebus_softc), simplebus_driver);
77 static devclass_t palmbus_devclass;
78 EARLY_DRIVER_MODULE(palmbus, ofwbus, palmbus_driver, palmbus_devclass, 0, 0,
79     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
80 MODULE_VERSION(palmbus, 1);
81