xref: /freebsd/sys/dev/pwm/ofw_pwm.c (revision 4b9d6057)
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/param.h>
29 #include <sys/systm.h>
30 #include <sys/bus.h>
31 #include <sys/kernel.h>
32 #include <sys/resource.h>
33 
34 #include <dev/ofw/ofw_bus.h>
35 #include <dev/ofw/ofw_bus_subr.h>
36 
37 #include <dev/pwm/ofw_pwm.h>
38 
39 int
40 pwm_get_by_ofw_propidx(device_t consumer, phandle_t node,
41     const char *prop_name, int idx, pwm_channel_t *out_channel)
42 {
43 	phandle_t xref;
44 	pcell_t *cells;
45 	struct pwm_channel channel;
46 	int ncells, rv;
47 
48 	rv = ofw_bus_parse_xref_list_alloc(node, prop_name, "#pwm-cells",
49 	  idx, &xref, &ncells, &cells);
50 	if (rv != 0)
51 		return (rv);
52 
53 	channel.dev = OF_device_from_xref(xref);
54 	if (channel.dev == NULL) {
55 		OF_prop_free(cells);
56 		return (ENODEV);
57 	}
58 
59 	channel.channel = cells[0];
60 	channel.period = cells[1];
61 
62 	if (ncells >= 3)
63 		channel.flags = cells[2];
64 
65 	*out_channel = malloc(sizeof(struct pwm_channel), M_DEVBUF, M_WAITOK | M_ZERO);
66 	**out_channel = channel;
67 	return (0);
68 }
69 
70 int
71 pwm_get_by_ofw_idx(device_t consumer, phandle_t node, int idx,
72     pwm_channel_t *out_channel)
73 {
74 
75 	return (pwm_get_by_ofw_propidx(consumer, node, "pwms", idx, out_channel));
76 }
77 
78 int
79 pwm_get_by_ofw_property(device_t consumer, phandle_t node,
80     const char *prop_name, pwm_channel_t *out_channel)
81 {
82 
83 	return (pwm_get_by_ofw_propidx(consumer, node, prop_name, 0, out_channel));
84 }
85 
86 int
87 pwm_get_by_ofw_name(device_t consumer, phandle_t node, const char *name,
88     pwm_channel_t *out_channel)
89 {
90 	int rv, idx;
91 
92 	rv = ofw_bus_find_string_index(node, "pwm-names", name, &idx);
93 	if (rv != 0)
94 		return (rv);
95 
96 	return (pwm_get_by_ofw_idx(consumer, node, idx, out_channel));
97 }
98