xref: /freebsd/sys/dev/pwm/ofw_pwm.c (revision 2f513db7)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 #include <sys/kernel.h>
35 #include <sys/resource.h>
36 
37 #include <dev/ofw/ofw_bus.h>
38 #include <dev/ofw/ofw_bus_subr.h>
39 
40 #include <dev/pwm/ofw_pwm.h>
41 
42 int
43 pwm_get_by_ofw_propidx(device_t consumer, phandle_t node,
44     const char *prop_name, int idx, pwm_channel_t *out_channel)
45 {
46 	phandle_t xref;
47 	pcell_t *cells;
48 	struct pwm_channel channel;
49 	int ncells, rv;
50 
51 	rv = ofw_bus_parse_xref_list_alloc(node, prop_name, "#pwm-cells",
52 	  idx, &xref, &ncells, &cells);
53 	if (rv != 0)
54 		return (rv);
55 
56 	channel.dev = OF_device_from_xref(xref);
57 	if (channel.dev == NULL) {
58 		OF_prop_free(cells);
59 		return (ENODEV);
60 	}
61 
62 	channel.channel = cells[0];
63 	channel.period = cells[1];
64 
65 	if (ncells >= 3)
66 		channel.flags = cells[2];
67 
68 	*out_channel = malloc(sizeof(struct pwm_channel), M_DEVBUF, M_WAITOK | M_ZERO);
69 	**out_channel = channel;
70 	return (0);
71 }
72 
73 int
74 pwm_get_by_ofw_idx(device_t consumer, phandle_t node, int idx,
75     pwm_channel_t *out_channel)
76 {
77 
78 	return (pwm_get_by_ofw_propidx(consumer, node, "pwms", idx, out_channel));
79 }
80 
81 int
82 pwm_get_by_ofw_property(device_t consumer, phandle_t node,
83     const char *prop_name, pwm_channel_t *out_channel)
84 {
85 
86 	return (pwm_get_by_ofw_propidx(consumer, node, prop_name, 0, out_channel));
87 }
88 
89 int
90 pwm_get_by_ofw_name(device_t consumer, phandle_t node, const char *name,
91     pwm_channel_t *out_channel)
92 {
93 	int rv, idx;
94 
95 	rv = ofw_bus_find_string_index(node, "pwm-names", name, &idx);
96 	if (rv != 0)
97 		return (rv);
98 
99 	return (pwm_get_by_ofw_idx(consumer, node, idx, out_channel));
100 }
101