drivers/regulator/of_regulator.c

   1 /*
   2  * OF helpers for regulator framework
   3  *
   4  * Copyright (C) 2011 Texas Instruments, Inc.
   5  * Rajendra Nayak <rnayak@ti.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/slab.h>
  15 #include <linux/of.h>
  16 #include <linux/regulator/machine.h>
  17
  18 static void of_get_regulation_constraints(struct device_node *np,
  19                                         struct regulator_init_data **init_data)
  20 {
  21         const __be32 *min_uV, *max_uV, *uV_offset;
  22         const __be32 *min_uA, *max_uA;
  23         struct regulation_constraints *constraints = &(*init_data)->constraints;
  24
  25         constraints->name = of_get_property(np, "regulator-name", NULL);
  26
  27         min_uV = of_get_property(np, "regulator-min-microvolt", NULL);
  28         if (min_uV)
  29                 constraints->min_uV = be32_to_cpu(*min_uV);
  30         max_uV = of_get_property(np, "regulator-max-microvolt", NULL);
  31         if (max_uV)
  32                 constraints->max_uV = be32_to_cpu(*max_uV);
  33
  34         /* Voltage change possible? */
  35         if (constraints->min_uV != constraints->max_uV)
  36                 constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
  37         /* Only one voltage?  Then make sure it's set. */
  38         if (constraints->min_uV == constraints->max_uV)
  39                 constraints->apply_uV = true;
  40
  41         uV_offset = of_get_property(np, "regulator-microvolt-offset", NULL);
  42         if (uV_offset)
  43                 constraints->uV_offset = be32_to_cpu(*uV_offset);
  44         min_uA = of_get_property(np, "regulator-min-microamp", NULL);
  45         if (min_uA)
  46                 constraints->min_uA = be32_to_cpu(*min_uA);
  47         max_uA = of_get_property(np, "regulator-max-microamp", NULL);
  48         if (max_uA)
  49                 constraints->max_uA = be32_to_cpu(*max_uA);
  50
  51         /* Current change possible? */
  52         if (constraints->min_uA != constraints->max_uA)
  53                 constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
  54
  55         if (of_find_property(np, "regulator-boot-on", NULL))
  56                 constraints->boot_on = true;
  57
  58         if (of_find_property(np, "regulator-always-on", NULL))
  59                 constraints->always_on = true;
  60         else /* status change should be possible if not always on. */
  61                 constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
  62 }
  63
  64 /**
  65  * of_get_regulator_init_data - extract regulator_init_data structure info
  66  * @dev: device requesting for regulator_init_data
  67  *
  68  * Populates regulator_init_data structure by extracting data from device
  69  * tree node, returns a pointer to the populated struture or NULL if memory
  70  * alloc fails.
  71  */
  72 struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
  73                                                 struct device_node *node)
  74 {
  75         struct regulator_init_data *init_data;
  76
  77         if (!node)
  78                 return NULL;
  79
  80         init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
  81         if (!init_data)
  82                 return NULL; /* Out of memory? */
  83
  84         of_get_regulation_constraints(node, &init_data);
  85         return init_data;
  86 }
  87 EXPORT_SYMBOL_GPL(of_get_regulator_init_data);