1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2019 Ian Lepore <ian@FreeBSD.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include <sys/param.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/libkern.h>
32 #include <sys/lock.h>
33 #include <sys/module.h>
34
35 #include <dev/fdt/fdt_common.h>
36 #include <dev/ofw/ofw_bus.h>
37 #include <dev/ofw/ofw_bus_subr.h>
38 #include <dev/ofw/openfirm.h>
39 #include <dev/pwm/pwmbus.h>
40
41 #include "pwmbus_if.h"
42
43 struct ofw_pwmbus_ivars {
44 struct pwmbus_ivars base;
45 struct ofw_bus_devinfo devinfo;
46 };
47
48 struct ofw_pwmbus_softc {
49 struct pwmbus_softc base;
50 };
51
52 /*
53 * bus_if methods...
54 */
55
56 static device_t
ofw_pwmbus_add_child(device_t dev,u_int order,const char * name,int unit)57 ofw_pwmbus_add_child(device_t dev, u_int order, const char *name, int unit)
58 {
59 device_t child;
60 struct ofw_pwmbus_ivars *ivars;
61
62 if ((ivars = malloc(sizeof(struct ofw_pwmbus_ivars), M_DEVBUF,
63 M_NOWAIT | M_ZERO)) == NULL) {
64 return (NULL);
65 }
66
67 if ((child = device_add_child_ordered(dev, order, name, unit)) == NULL) {
68 free(ivars, M_DEVBUF);
69 return (NULL);
70 }
71
72 ivars->devinfo.obd_node = -1;
73 device_set_ivars(child, ivars);
74
75 return (child);
76 }
77
78 static void
ofw_pwmbus_child_deleted(device_t dev,device_t child)79 ofw_pwmbus_child_deleted(device_t dev, device_t child)
80 {
81 struct ofw_pwmbus_ivars *ivars;
82
83 ivars = device_get_ivars(child);
84 if (ivars != NULL) {
85 ofw_bus_gen_destroy_devinfo(&ivars->devinfo);
86 free(ivars, M_DEVBUF);
87 }
88 }
89
90 static const struct ofw_bus_devinfo *
ofw_pwmbus_get_devinfo(device_t bus,device_t dev)91 ofw_pwmbus_get_devinfo(device_t bus, device_t dev)
92 {
93 struct ofw_pwmbus_ivars *ivars;
94
95 ivars = device_get_ivars(dev);
96 return (&ivars->devinfo);
97 }
98
99 /*
100 * device_if methods...
101 */
102
103 static int
ofw_pwmbus_probe(device_t dev)104 ofw_pwmbus_probe(device_t dev)
105 {
106
107 if (ofw_bus_get_node(dev) == -1) {
108 return (ENXIO);
109 }
110 device_set_desc(dev, "OFW PWM bus");
111
112 return (BUS_PROBE_DEFAULT);
113 }
114
115 static int
ofw_pwmbus_attach(device_t dev)116 ofw_pwmbus_attach(device_t dev)
117 {
118 struct ofw_pwmbus_softc *sc;
119 struct ofw_pwmbus_ivars *ivars;
120 phandle_t node;
121 device_t child, parent;
122 pcell_t chan;
123 bool any_children;
124
125 sc = device_get_softc(dev);
126 sc->base.dev = dev;
127 parent = device_get_parent(dev);
128
129 if (PWMBUS_CHANNEL_COUNT(parent, &sc->base.nchannels) != 0 ||
130 sc->base.nchannels == 0) {
131 device_printf(dev, "No channels on parent %s\n",
132 device_get_nameunit(parent));
133 return (ENXIO);
134 }
135
136 /*
137 * Attach the children found in the fdt node of the hardware controller.
138 * Hardware controllers must implement the ofw_bus_get_node method so
139 * that our call to ofw_bus_get_node() gets back the controller's node.
140 */
141 any_children = false;
142 node = ofw_bus_get_node(dev);
143 for (node = OF_child(node); node != 0; node = OF_peer(node)) {
144 /*
145 * The child has to have a reg property; its value is the
146 * channel number so range-check it.
147 */
148 if (OF_getencprop(node, "reg", &chan, sizeof(chan)) == -1)
149 continue;
150 if (chan >= sc->base.nchannels)
151 continue;
152
153 if ((child = ofw_pwmbus_add_child(dev, 0, NULL, -1)) == NULL)
154 continue;
155
156 ivars = device_get_ivars(child);
157 ivars->base.pi_channel = chan;
158
159 /* Set up the standard ofw devinfo. */
160 if (ofw_bus_gen_setup_devinfo(&ivars->devinfo, node) != 0) {
161 device_delete_child(dev, child);
162 continue;
163 }
164 any_children = true;
165 }
166
167 /*
168 * If we didn't find any children in the fdt data, add a pwmc(4) child
169 * for each channel, like the base pwmbus does. The idea is that if
170 * there is any fdt data, then we do exactly what it says and nothing
171 * more, otherwise we just provide generic userland access to all the
172 * pwm channels that exist like the base pwmbus's attach code does.
173 */
174 if (!any_children) {
175 for (chan = 0; chan < sc->base.nchannels; ++chan) {
176 child = ofw_pwmbus_add_child(dev, 0, "pwmc", -1);
177 if (child == NULL) {
178 device_printf(dev, "failed to add pwmc child "
179 " device for channel %u\n", chan);
180 continue;
181 }
182 ivars = device_get_ivars(child);
183 ivars->base.pi_channel = chan;
184 }
185 }
186 bus_enumerate_hinted_children(dev);
187 bus_identify_children(dev);
188 bus_attach_children(dev);
189
190 return (0);
191 }
192
193 static device_method_t ofw_pwmbus_methods[] = {
194 /* Device interface */
195 DEVMETHOD(device_probe, ofw_pwmbus_probe),
196 DEVMETHOD(device_attach, ofw_pwmbus_attach),
197
198 /* Bus interface */
199 DEVMETHOD(bus_child_pnpinfo, ofw_bus_gen_child_pnpinfo),
200 DEVMETHOD(bus_add_child, ofw_pwmbus_add_child),
201 DEVMETHOD(bus_child_deleted, ofw_pwmbus_child_deleted),
202
203 /* ofw_bus interface */
204 DEVMETHOD(ofw_bus_get_devinfo, ofw_pwmbus_get_devinfo),
205 DEVMETHOD(ofw_bus_get_compat, ofw_bus_gen_get_compat),
206 DEVMETHOD(ofw_bus_get_model, ofw_bus_gen_get_model),
207 DEVMETHOD(ofw_bus_get_name, ofw_bus_gen_get_name),
208 DEVMETHOD(ofw_bus_get_node, ofw_bus_gen_get_node),
209 DEVMETHOD(ofw_bus_get_type, ofw_bus_gen_get_type),
210
211 DEVMETHOD_END
212 };
213
214 DEFINE_CLASS_1(pwmbus, ofw_pwmbus_driver, ofw_pwmbus_methods,
215 sizeof(struct pwmbus_softc), pwmbus_driver);
216 EARLY_DRIVER_MODULE(ofw_pwmbus, pwm, ofw_pwmbus_driver, 0, 0,
217 BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
218 MODULE_VERSION(ofw_pwmbus, 1);
219 MODULE_DEPEND(ofw_pwmbus, pwmbus, 1, 1, 1);
220