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/slab.h>
  14 #include <linux/of.h>
  15 #include <linux/regulator/machine.h>
  16
  17 static void of_get_regulation_constraints(struct device_node *np,
  18                                         struct regulator_init_data **init_data)
  19 {
  20         const __be32 *min_uV, *max_uV, *uV_offset;
  21         const __be32 *min_uA, *max_uA;
  22         struct regulation_constraints *constraints = &(*init_data)->constraints;
  23
  24         constraints->name = of_get_property(np, "regulator-name", NULL);
  25
  26         min_uV = of_get_property(np, "regulator-min-microvolt", NULL);
  27         if (min_uV)
  28                 constraints->min_uV = be32_to_cpu(*min_uV);
  29         max_uV = of_get_property(np, "regulator-max-microvolt", NULL);
  30         if (max_uV)
  31                 constraints->max_uV = be32_to_cpu(*max_uV);
  32
  33         /* Voltage change possible? */
  34         if (constraints->min_uV != constraints->max_uV)
  35                 constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
  36
  37         uV_offset = of_get_property(np, "regulator-microvolt-offset", NULL);
  38         if (uV_offset)
  39                 constraints->uV_offset = be32_to_cpu(*uV_offset);
  40         min_uA = of_get_property(np, "regulator-min-microamp", NULL);
  41         if (min_uA)
  42                 constraints->min_uA = be32_to_cpu(*min_uA);
  43         max_uA = of_get_property(np, "regulator-max-microamp", NULL);
  44         if (max_uA)
  45                 constraints->max_uA = be32_to_cpu(*max_uA);
  46
  47         /* Current change possible? */
  48         if (constraints->min_uA != constraints->max_uA)
  49                 constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
  50
  51         if (of_find_property(np, "regulator-boot-on", NULL))
  52                 constraints->boot_on = true;
  53
  54         if (of_find_property(np, "regulator-always-on", NULL))
  55                 constraints->always_on = true;
  56         else /* status change should be possible if not always on. */
  57                 constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
  58 }
  59
  60 /**
  61  * of_get_regulator_init_data - extract regulator_init_data structure info
  62  * @dev: device requesting for regulator_init_data
  63  *
  64  * Populates regulator_init_data structure by extracting data from device
  65  * tree node, returns a pointer to the populated struture or NULL if memory
  66  * alloc fails.
  67  */
  68 struct regulator_init_data *of_get_regulator_init_data(struct device *dev)
  69 {
  70         struct regulator_init_data *init_data;
  71
  72         if (!dev->of_node)
  73                 return NULL;
  74
  75         init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
  76         if (!init_data)
  77                 return NULL; /* Out of memory? */
  78
  79         of_get_regulation_constraints(dev->of_node, &init_data);
  80         return init_data;
  81 }