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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 (at) 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