fdt_regulator.c revision 1.8 
1/* $NetBSD: fdt_regulator.c,v 1.8 2019/05/27 23:18:33 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 1.8 2019/05/27 23:18:33 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
40struct fdtbus_regulator_controller {
41	device_t rc_dev;
42	int rc_phandle;
43	const struct fdtbus_regulator_controller_func *rc_funcs;
44
45	u_int rc_enable_ramp_delay;
46
47	LIST_ENTRY(fdtbus_regulator_controller) rc_next;
48};
49
50static LIST_HEAD(, fdtbus_regulator_controller) fdtbus_regulator_controllers =
51    LIST_HEAD_INITIALIZER(fdtbus_regulator_controllers);
52
53int
54fdtbus_register_regulator_controller(device_t dev, int phandle,
55    const struct fdtbus_regulator_controller_func *funcs)
56{
57	struct fdtbus_regulator_controller *rc;
58
59	rc = kmem_zalloc(sizeof(*rc), KM_SLEEP);
60	rc->rc_dev = dev;
61	rc->rc_phandle = phandle;
62	rc->rc_funcs = funcs;
63
64	of_getprop_uint32(phandle, "regulator-enable-ramp-delay", &rc->rc_enable_ramp_delay);
65
66	LIST_INSERT_HEAD(&fdtbus_regulator_controllers, rc, rc_next);
67
68	return 0;
69}
70
71static struct fdtbus_regulator_controller *
72fdtbus_get_regulator_controller(int phandle)
73{
74	struct fdtbus_regulator_controller *rc;
75
76	LIST_FOREACH(rc, &fdtbus_regulator_controllers, rc_next) {
77		if (rc->rc_phandle == phandle)
78			return rc;
79	}
80
81	return NULL;
82}
83
84struct fdtbus_regulator *
85fdtbus_regulator_acquire(int phandle, const char *prop)
86{
87	struct fdtbus_regulator_controller *rc;
88	struct fdtbus_regulator *reg;
89	int regulator_phandle;
90	int error;
91
92	regulator_phandle = fdtbus_get_phandle(phandle, prop);
93	if (regulator_phandle == -1) {
94		return NULL;
95	}
96
97	rc = fdtbus_get_regulator_controller(regulator_phandle);
98	if (rc == NULL) {
99		return NULL;
100	}
101
102	error = rc->rc_funcs->acquire(rc->rc_dev);
103	if (error) {
104		aprint_error_dev(rc->rc_dev, "failed to acquire regulator: %d\n", error);
105		return NULL;
106	}
107
108	reg = kmem_alloc(sizeof(*reg), KM_SLEEP);
109	reg->reg_rc = rc;
110
111	return reg;
112}
113
114void
115fdtbus_regulator_release(struct fdtbus_regulator *reg)
116{
117	struct fdtbus_regulator_controller *rc = reg->reg_rc;
118
119	rc->rc_funcs->release(rc->rc_dev);
120
121	kmem_free(reg, sizeof(*reg));
122}
123
124int
125fdtbus_regulator_enable(struct fdtbus_regulator *reg)
126{
127	struct fdtbus_regulator_controller *rc = reg->reg_rc;
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 = reg->reg_rc;
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 = reg->reg_rc;
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 = reg->reg_rc;
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 = reg->reg_rc;
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