xref: /freebsd/sys/dev/spibus/ofw_spibus.c (revision f5463265955b829775bbb32e1fd0bc11dafc36ce)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2009, Nathan Whitehorn <nwhitehorn@FreeBSD.org>
5  * Copyright (c) 2013 The FreeBSD Foundation
6  * All rights reserved.
7  *
8  * Portions of this software were developed by Oleksandr Rybalko
9  * under sponsorship from the FreeBSD Foundation.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice unmodified, this list of conditions, and the following
16  *    disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/param.h>
34 #include <sys/bus.h>
35 #include <sys/kernel.h>
36 #include <sys/libkern.h>
37 #include <sys/lock.h>
38 #include <sys/module.h>
39 #include <sys/mutex.h>
40 
41 #include <dev/fdt/fdt_common.h>
42 #include <dev/spibus/spi.h>
43 #include <dev/spibus/spibusvar.h>
44 #include <dev/ofw/ofw_bus.h>
45 #include <dev/ofw/ofw_bus_subr.h>
46 #include <dev/ofw/openfirm.h>
47 
48 #include "spibus_if.h"
49 
50 struct ofw_spibus_devinfo {
51 	struct spibus_ivar	opd_dinfo;
52 	struct ofw_bus_devinfo	opd_obdinfo;
53 };
54 
55 /* Methods */
56 static device_probe_t ofw_spibus_probe;
57 static device_attach_t ofw_spibus_attach;
58 static device_t ofw_spibus_add_child(device_t dev, u_int order,
59     const char *name, int unit);
60 static const struct ofw_bus_devinfo *ofw_spibus_get_devinfo(device_t bus,
61     device_t dev);
62 
63 static int
64 ofw_spibus_probe(device_t dev)
65 {
66 
67 	if (ofw_bus_get_node(dev) == -1)
68 		return (ENXIO);
69 	device_set_desc(dev, "OFW SPI bus");
70 
71 	return (BUS_PROBE_DEFAULT + 1);
72 }
73 
74 static int
75 ofw_spibus_attach(device_t dev)
76 {
77 	struct spibus_softc *sc = device_get_softc(dev);
78 	struct ofw_spibus_devinfo *dinfo;
79 	phandle_t child;
80 	pcell_t clock, paddr;
81 	device_t childdev;
82 	uint32_t mode = SPIBUS_MODE_NONE;
83 
84 	sc->dev = dev;
85 
86 	bus_generic_probe(dev);
87 	bus_enumerate_hinted_children(dev);
88 
89 	/*
90 	 * Attach those children represented in the device tree.
91 	 */
92 	for (child = OF_child(ofw_bus_get_node(dev)); child != 0;
93 	    child = OF_peer(child)) {
94 		/*
95 		 * Try to get the CS number first from the spi-chipselect
96 		 * property, then try the reg property.
97 		 */
98 		if (OF_getencprop(child, "spi-chipselect", &paddr,
99 		    sizeof(paddr)) == -1) {
100 			if (OF_getencprop(child, "reg", &paddr,
101 			    sizeof(paddr)) == -1)
102 				continue;
103 		}
104 
105 		/*
106 		 * Try to get the cpol/cpha mode
107 		 */
108 		if (OF_hasprop(child, "spi-cpol"))
109 			mode = SPIBUS_MODE_CPOL;
110 		if (OF_hasprop(child, "spi-cpha")) {
111 			if (mode == SPIBUS_MODE_CPOL)
112 				mode = SPIBUS_MODE_CPOL_CPHA;
113 			else
114 				mode = SPIBUS_MODE_CPHA;
115 		}
116 
117 		/*
118 		 * Try to get the CS polarity
119 		 */
120 		if (OF_hasprop(child, "spi-cs-high"))
121 			paddr |= SPIBUS_CS_HIGH;
122 
123 		/*
124 		 * Get the maximum clock frequency for device, zero means
125 		 * use the default bus speed.
126 		 *
127 		 * XXX Note that the current (2018-04-07) dts bindings say that
128 		 * spi-max-frequency is a required property (but says nothing of
129 		 * how to interpret a value of zero).
130 		 */
131 		if (OF_getencprop(child, "spi-max-frequency", &clock,
132 		    sizeof(clock)) == -1)
133 			clock = 0;
134 
135 		/*
136 		 * Now set up the SPI and OFW bus layer devinfo and add it
137 		 * to the bus.
138 		 */
139 		dinfo = malloc(sizeof(struct ofw_spibus_devinfo), M_DEVBUF,
140 		    M_NOWAIT | M_ZERO);
141 		if (dinfo == NULL)
142 			continue;
143 		dinfo->opd_dinfo.cs = paddr;
144 		dinfo->opd_dinfo.clock = clock;
145 		dinfo->opd_dinfo.mode = mode;
146 		if (ofw_bus_gen_setup_devinfo(&dinfo->opd_obdinfo, child) !=
147 		    0) {
148 			free(dinfo, M_DEVBUF);
149 			continue;
150 		}
151 		childdev = device_add_child(dev, NULL, -1);
152 
153 		resource_list_init(&dinfo->opd_dinfo.rl);
154 		ofw_bus_intr_to_rl(childdev, child,
155 		    &dinfo->opd_dinfo.rl, NULL);
156 		device_set_ivars(childdev, dinfo);
157 	}
158 
159 	return (bus_generic_attach(dev));
160 }
161 
162 static device_t
163 ofw_spibus_add_child(device_t dev, u_int order, const char *name, int unit)
164 {
165 	device_t child;
166 	struct ofw_spibus_devinfo *devi;
167 
168 	child = device_add_child_ordered(dev, order, name, unit);
169 	if (child == NULL)
170 		return (child);
171 	devi = malloc(sizeof(struct ofw_spibus_devinfo), M_DEVBUF,
172 	    M_NOWAIT | M_ZERO);
173 	if (devi == NULL) {
174 		device_delete_child(dev, child);
175 		return (0);
176 	}
177 
178 	/*
179 	 * NULL all the OFW-related parts of the ivars for non-OFW
180 	 * children.
181 	 */
182 	devi->opd_obdinfo.obd_node = -1;
183 	devi->opd_obdinfo.obd_name = NULL;
184 	devi->opd_obdinfo.obd_compat = NULL;
185 	devi->opd_obdinfo.obd_type = NULL;
186 	devi->opd_obdinfo.obd_model = NULL;
187 
188 	device_set_ivars(child, devi);
189 
190 	return (child);
191 }
192 
193 static const struct ofw_bus_devinfo *
194 ofw_spibus_get_devinfo(device_t bus, device_t dev)
195 {
196 	struct ofw_spibus_devinfo *dinfo;
197 
198 	dinfo = device_get_ivars(dev);
199 	return (&dinfo->opd_obdinfo);
200 }
201 
202 static struct resource_list *
203 ofw_spibus_get_resource_list(device_t bus __unused, device_t child)
204 {
205 	struct spibus_ivar *devi;
206 
207 	devi = SPIBUS_IVAR(child);
208 	return (&devi->rl);
209 }
210 
211 static device_method_t ofw_spibus_methods[] = {
212 	/* Device interface */
213 	DEVMETHOD(device_probe,		ofw_spibus_probe),
214 	DEVMETHOD(device_attach,	ofw_spibus_attach),
215 
216 	/* Bus interface */
217 	DEVMETHOD(bus_child_pnpinfo,	ofw_bus_gen_child_pnpinfo),
218 	DEVMETHOD(bus_add_child,	ofw_spibus_add_child),
219 	DEVMETHOD(bus_get_resource_list, ofw_spibus_get_resource_list),
220 
221 	/* ofw_bus interface */
222 	DEVMETHOD(ofw_bus_get_devinfo,	ofw_spibus_get_devinfo),
223 	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
224 	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
225 	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
226 	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
227 	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
228 
229 	DEVMETHOD_END
230 };
231 
232 DEFINE_CLASS_1(spibus, ofw_spibus_driver, ofw_spibus_methods,
233     sizeof(struct spibus_softc), spibus_driver);
234 DRIVER_MODULE(ofw_spibus, spi, ofw_spibus_driver, 0, 0);
235 MODULE_VERSION(ofw_spibus, 1);
236 MODULE_DEPEND(ofw_spibus, spibus, 1, 1, 1);
237