fdt_regulator.c revision 1.9 
1/* $NetBSD: fdt_regulator.c,v 1.9 2021/08/08 15:23:42 jmcneill Exp $ */
2
3/*-
4 * Copyright (c) 2015 Jared D. McNeill <jmcneill@invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__KERNEL_RCSID(0, "$NetBSD: fdt_regulator.c,v 1.9 2021/08/08 15:23:42 jmcneill Exp $");
31
32#include <sys/param.h>
33#include <sys/bus.h>
34#include <sys/kmem.h>
35#include <sys/queue.h>
36
37#include <libfdt.h>
38#include <dev/fdt/fdtvar.h>
39
40#define	REGULATOR_TO_RC(_reg)	\
41	container_of((_reg), struct fdtbus_regulator_controller, rc_reg)
42
43struct fdtbus_regulator_controller {
44	device_t rc_dev;
45	int rc_phandle;
46	const struct fdtbus_regulator_controller_func *rc_funcs;
47
48	u_int rc_enable_ramp_delay;
49
50	struct fdtbus_regulator rc_reg;	/* handle returned by acquire() */
51
52	LIST_ENTRY(fdtbus_regulator_controller) rc_next;
53};
54
55static LIST_HEAD(, fdtbus_regulator_controller) fdtbus_regulator_controllers =
56    LIST_HEAD_INITIALIZER(fdtbus_regulator_controllers);
57
58int
59fdtbus_register_regulator_controller(device_t dev, int phandle,
60    const struct fdtbus_regulator_controller_func *funcs)
61{
62	struct fdtbus_regulator_controller *rc;
63
64	rc = kmem_zalloc(sizeof(*rc), KM_SLEEP);
65	rc->rc_dev = dev;
66	rc->rc_phandle = phandle;
67	rc->rc_funcs = funcs;
68	rc->rc_reg.reg_rc = rc;
69
70	of_getprop_uint32(phandle, "regulator-enable-ramp-delay", &rc->rc_enable_ramp_delay);
71
72	LIST_INSERT_HEAD(&fdtbus_regulator_controllers, rc, rc_next);
73
74	return 0;
75}
76
77static struct fdtbus_regulator_controller *
78fdtbus_get_regulator_controller(int phandle)
79{
80	struct fdtbus_regulator_controller *rc;
81
82	LIST_FOREACH(rc, &fdtbus_regulator_controllers, rc_next) {
83		if (rc->rc_phandle == phandle)
84			return rc;
85	}
86
87	return NULL;
88}
89
90struct fdtbus_regulator *
91fdtbus_regulator_acquire(int phandle, const char *prop)
92{
93	struct fdtbus_regulator_controller *rc;
94	int regulator_phandle;
95	int error;
96
97	regulator_phandle = fdtbus_get_phandle(phandle, prop);
98	if (regulator_phandle == -1) {
99		return NULL;
100	}
101
102	rc = fdtbus_get_regulator_controller(regulator_phandle);
103	if (rc == NULL) {
104		return NULL;
105	}
106
107	error = rc->rc_funcs->acquire(rc->rc_dev);
108	if (error) {
109		aprint_error_dev(rc->rc_dev, "failed to acquire regulator: %d\n", error);
110		return NULL;
111	}
112
113	return &rc->rc_reg;
114}
115
116void
117fdtbus_regulator_release(struct fdtbus_regulator *reg)
118{
119	struct fdtbus_regulator_controller *rc = REGULATOR_TO_RC(reg);
120
121	rc->rc_funcs->release(rc->rc_dev);
122}
123
124int
125fdtbus_regulator_enable(struct fdtbus_regulator *reg)
126{
127	struct fdtbus_regulator_controller *rc = REGULATOR_TO_RC(reg);
128	int error;
129
130	error = rc->rc_funcs->enable(rc->rc_dev, true);
131	if (error != 0)
132		return error;
133
134	if (rc->rc_enable_ramp_delay != 0)
135		delay(rc->rc_enable_ramp_delay);
136
137	return 0;
138}
139
140int
141fdtbus_regulator_disable(struct fdtbus_regulator *reg)
142{
143	struct fdtbus_regulator_controller *rc = REGULATOR_TO_RC(reg);
144
145	if (of_hasprop(rc->rc_phandle, "regulator-always-on"))
146		return EIO;
147
148	return rc->rc_funcs->enable(rc->rc_dev, false);
149}
150
151int
152fdtbus_regulator_set_voltage(struct fdtbus_regulator *reg, u_int min_uvol,
153    u_int max_uvol)
154{
155	struct fdtbus_regulator_controller *rc = REGULATOR_TO_RC(reg);
156
157	if (rc->rc_funcs->set_voltage == NULL)
158		return EINVAL;
159
160	return rc->rc_funcs->set_voltage(rc->rc_dev, min_uvol, max_uvol);
161}
162
163int
164fdtbus_regulator_get_voltage(struct fdtbus_regulator *reg, u_int *puvol)
165{
166	struct fdtbus_regulator_controller *rc = REGULATOR_TO_RC(reg);
167
168	if (rc->rc_funcs->get_voltage == NULL)
169		return EINVAL;
170
171	return rc->rc_funcs->get_voltage(rc->rc_dev, puvol);
172}
173
174int
175fdtbus_regulator_supports_voltage(struct fdtbus_regulator *reg, u_int min_uvol,
176    u_int max_uvol)
177{
178	struct fdtbus_regulator_controller *rc = REGULATOR_TO_RC(reg);
179	u_int uvol;
180
181	if (rc->rc_funcs->set_voltage == NULL)
182		return EINVAL;
183
184	if (of_getprop_uint32(rc->rc_phandle, "regulator-min-microvolt", &uvol) == 0) {
185		if (uvol < min_uvol)
186			return ERANGE;
187	}
188	if (of_getprop_uint32(rc->rc_phandle, "regulator-max-microvolt", &uvol) == 0) {
189		if (uvol > max_uvol)
190			return ERANGE;
191	}
192
193	return 0;
194}
195