drivers/power/regulator/fixed.c

   1 /*
   2  *  Copyright (C) 2015 Samsung Electronics
   3  *
   4  *  Przemyslaw Marczak <p.marczak@samsung.com>
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <common.h>
  10 #include <fdtdec.h>
  11 #include <errno.h>
  12 #include <dm.h>
  13 #include <i2c.h>
  14 #include <asm/gpio.h>
  15 #include <power/pmic.h>
  16 #include <power/regulator.h>
  17
  18 DECLARE_GLOBAL_DATA_PTR;
  19
  20 struct fixed_regulator_platdata {
  21         struct gpio_desc gpio; /* GPIO for regulator enable control */
  22         unsigned int startup_delay_us;
  23 };
  24
  25 static int fixed_regulator_ofdata_to_platdata(struct udevice *dev)
  26 {
  27         struct dm_regulator_uclass_platdata *uc_pdata;
  28         struct fixed_regulator_platdata *dev_pdata;
  29         struct gpio_desc *gpio;
  30         const void *blob = gd->fdt_blob;
  31         int node = dev->of_offset, flags = GPIOD_IS_OUT;
  32         int ret;
  33
  34         dev_pdata = dev_get_platdata(dev);
  35         uc_pdata = dev_get_uclass_platdata(dev);
  36         if (!uc_pdata)
  37                 return -ENXIO;
  38
  39         /* Set type to fixed */
  40         uc_pdata->type = REGULATOR_TYPE_FIXED;
  41
  42         if (fdtdec_get_bool(blob, node, "enable-active-high"))
  43                 flags |= GPIOD_IS_OUT_ACTIVE;
  44
  45         /* Get fixed regulator optional enable GPIO desc */
  46         gpio = &dev_pdata->gpio;
  47         ret = gpio_request_by_name(dev, "gpio", 0, gpio, flags);
  48         if (ret) {
  49                 debug("Fixed regulator optional enable GPIO - not found! Error: %d\n",
  50                       ret);
  51                 if (ret != -ENOENT)
  52                         return ret;
  53         }
  54
  55         /* Get optional ramp up delay */
  56         dev_pdata->startup_delay_us = fdtdec_get_uint(gd->fdt_blob,
  57                                                       dev->of_offset,
  58                                                       "startup-delay-us", 0);
  59
  60         return 0;
  61 }
  62
  63 static int fixed_regulator_get_value(struct udevice *dev)
  64 {
  65         struct dm_regulator_uclass_platdata *uc_pdata;
  66
  67         uc_pdata = dev_get_uclass_platdata(dev);
  68         if (!uc_pdata)
  69                 return -ENXIO;
  70
  71         if (uc_pdata->min_uV != uc_pdata->max_uV) {
  72                 debug("Invalid constraints for: %s\n", uc_pdata->name);
  73                 return -EINVAL;
  74         }
  75
  76         return uc_pdata->min_uV;
  77 }
  78
  79 static int fixed_regulator_get_current(struct udevice *dev)
  80 {
  81         struct dm_regulator_uclass_platdata *uc_pdata;
  82
  83         uc_pdata = dev_get_uclass_platdata(dev);
  84         if (!uc_pdata)
  85                 return -ENXIO;
  86
  87         if (uc_pdata->min_uA != uc_pdata->max_uA) {
  88                 debug("Invalid constraints for: %s\n", uc_pdata->name);
  89                 return -EINVAL;
  90         }
  91
  92         return uc_pdata->min_uA;
  93 }
  94
  95 static bool fixed_regulator_get_enable(struct udevice *dev)
  96 {
  97         struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
  98
  99         /* Enable GPIO is optional */
 100         if (!dev_pdata->gpio.dev)
 101                 return true;
 102
 103         return dm_gpio_get_value(&dev_pdata->gpio);
 104 }
 105
 106 static int fixed_regulator_set_enable(struct udevice *dev, bool enable)
 107 {
 108         struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
 109         int ret;
 110
 111         /* Enable GPIO is optional */
 112         if (!dev_pdata->gpio.dev) {
 113                 if (!enable)
 114                         return -ENOSYS;
 115                 return 0;
 116         }
 117
 118         ret = dm_gpio_set_value(&dev_pdata->gpio, enable);
 119         if (ret) {
 120                 error("Can't set regulator : %s gpio to: %d\n", dev->name,
 121                       enable);
 122                 return ret;
 123         }
 124
 125         if (enable && dev_pdata->startup_delay_us)
 126                 udelay(dev_pdata->startup_delay_us);
 127
 128         return 0;
 129 }
 130
 131 static const struct dm_regulator_ops fixed_regulator_ops = {
 132         .get_value      = fixed_regulator_get_value,
 133         .get_current    = fixed_regulator_get_current,
 134         .get_enable     = fixed_regulator_get_enable,
 135         .set_enable     = fixed_regulator_set_enable,
 136 };
 137
 138 static const struct udevice_id fixed_regulator_ids[] = {
 139         { .compatible = "regulator-fixed" },
 140         { },
 141 };
 142
 143 U_BOOT_DRIVER(fixed_regulator) = {
 144         .name = "fixed regulator",
 145         .id = UCLASS_REGULATOR,
 146         .ops = &fixed_regulator_ops,
 147         .of_match = fixed_regulator_ids,
 148         .ofdata_to_platdata = fixed_regulator_ofdata_to_platdata,
 149         .platdata_auto_alloc_size = sizeof(struct fixed_regulator_platdata),
 150 };