xref: /freebsd/sys/dev/pwm/ofw_pwm.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2018 Emmanuel Vadot <manu@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/cdefs.h>
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/bus.h>
32 #include <sys/kernel.h>
33 #include <sys/resource.h>
34 
35 #include <dev/ofw/ofw_bus.h>
36 #include <dev/ofw/ofw_bus_subr.h>
37 
38 #include <dev/pwm/ofw_pwm.h>
39 
40 int
41 pwm_get_by_ofw_propidx(device_t consumer, phandle_t node,
42     const char *prop_name, int idx, pwm_channel_t *out_channel)
43 {
44 	phandle_t xref;
45 	pcell_t *cells;
46 	struct pwm_channel channel;
47 	int ncells, rv;
48 
49 	rv = ofw_bus_parse_xref_list_alloc(node, prop_name, "#pwm-cells",
50 	  idx, &xref, &ncells, &cells);
51 	if (rv != 0)
52 		return (rv);
53 
54 	channel.dev = OF_device_from_xref(xref);
55 	if (channel.dev == NULL) {
56 		OF_prop_free(cells);
57 		return (ENODEV);
58 	}
59 
60 	channel.channel = cells[0];
61 	channel.period = cells[1];
62 
63 	if (ncells >= 3)
64 		channel.flags = cells[2];
65 
66 	*out_channel = malloc(sizeof(struct pwm_channel), M_DEVBUF, M_WAITOK | M_ZERO);
67 	**out_channel = channel;
68 	return (0);
69 }
70 
71 int
72 pwm_get_by_ofw_idx(device_t consumer, phandle_t node, int idx,
73     pwm_channel_t *out_channel)
74 {
75 
76 	return (pwm_get_by_ofw_propidx(consumer, node, "pwms", idx, out_channel));
77 }
78 
79 int
80 pwm_get_by_ofw_property(device_t consumer, phandle_t node,
81     const char *prop_name, pwm_channel_t *out_channel)
82 {
83 
84 	return (pwm_get_by_ofw_propidx(consumer, node, prop_name, 0, out_channel));
85 }
86 
87 int
88 pwm_get_by_ofw_name(device_t consumer, phandle_t node, const char *name,
89     pwm_channel_t *out_channel)
90 {
91 	int rv, idx;
92 
93 	rv = ofw_bus_find_string_index(node, "pwm-names", name, &idx);
94 	if (rv != 0)
95 		return (rv);
96 
97 	return (pwm_get_by_ofw_idx(consumer, node, idx, out_channel));
98 }
99