xref: /netbsd-src/sys/dev/fdt/fdt_regulator.c (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
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 
40 struct 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 
50 static LIST_HEAD(, fdtbus_regulator_controller) fdtbus_regulator_controllers =
51     LIST_HEAD_INITIALIZER(fdtbus_regulator_controllers);
52 
53 int
54 fdtbus_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 
71 static struct fdtbus_regulator_controller *
72 fdtbus_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 
84 struct fdtbus_regulator *
85 fdtbus_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 
114 void
115 fdtbus_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 
124 int
125 fdtbus_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 
140 int
141 fdtbus_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 
151 int
152 fdtbus_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 
163 int
164 fdtbus_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 
174 int
175 fdtbus_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