drivers/power/pmic/as3722.c

   1 /*
   2  * Copyright (C) 2014 NVIDIA Corporation
   3  *
   4  * SPDX-License-Identifier: GPL-2.0+
   5  */
   6
   7 #define pr_fmt(fmt) "as3722: " fmt
   8
   9 #include <common.h>
  10 #include <dm.h>
  11 #include <errno.h>
  12 #include <fdtdec.h>
  13 #include <i2c.h>
  14 #include <dm/lists.h>
  15 #include <power/as3722.h>
  16 #include <power/pmic.h>
  17
  18 #define AS3722_NUM_OF_REGS      0x92
  19
  20 static int as3722_read(struct udevice *dev, uint reg, uint8_t *buff, int len)
  21 {
  22         int ret;
  23
  24         ret = dm_i2c_read(dev, reg, buff, len);
  25         if (ret < 0)
  26                 return ret;
  27
  28         return 0;
  29 }
  30
  31 static int as3722_write(struct udevice *dev, uint reg, const uint8_t *buff,
  32                         int len)
  33 {
  34         int ret;
  35
  36         ret = dm_i2c_write(dev, reg, buff, len);
  37         if (ret < 0)
  38                 return ret;
  39
  40         return 0;
  41 }
  42
  43 static int as3722_read_id(struct udevice *dev, uint *idp, uint *revisionp)
  44 {
  45         int ret;
  46
  47         ret = pmic_reg_read(dev, AS3722_ASIC_ID1);
  48         if (ret < 0) {
  49                 error("failed to read ID1 register: %d", ret);
  50                 return ret;
  51         }
  52         *idp = ret;
  53
  54         ret = pmic_reg_read(dev, AS3722_ASIC_ID2);
  55         if (ret < 0) {
  56                 error("failed to read ID2 register: %d", ret);
  57                 return ret;
  58         }
  59         *revisionp = ret;
  60
  61         return 0;
  62 }
  63
  64 /* TODO(treding@nvidia.com): Add proper regulator support to avoid this */
  65 int as3722_sd_set_voltage(struct udevice *dev, unsigned int sd, u8 value)
  66 {
  67         int ret;
  68
  69         if (sd > 6)
  70                 return -EINVAL;
  71
  72         ret = pmic_reg_write(dev, AS3722_SD_VOLTAGE(sd), value);
  73         if (ret < 0) {
  74                 error("failed to write SD%u voltage register: %d", sd, ret);
  75                 return ret;
  76         }
  77
  78         return 0;
  79 }
  80
  81 int as3722_ldo_set_voltage(struct udevice *dev, unsigned int ldo, u8 value)
  82 {
  83         int ret;
  84
  85         if (ldo > 11)
  86                 return -EINVAL;
  87
  88         ret = pmic_reg_write(dev, AS3722_LDO_VOLTAGE(ldo), value);
  89         if (ret < 0) {
  90                 error("failed to write LDO%u voltage register: %d", ldo,
  91                       ret);
  92                 return ret;
  93         }
  94
  95         return 0;
  96 }
  97
  98 static int as3722_probe(struct udevice *dev)
  99 {
 100         uint id, revision;
 101         int ret;
 102
 103         ret = as3722_read_id(dev, &id, &revision);
 104         if (ret < 0) {
 105                 error("failed to read ID: %d", ret);
 106                 return ret;
 107         }
 108
 109         if (id != AS3722_DEVICE_ID) {
 110                 error("unknown device");
 111                 return -ENOENT;
 112         }
 113
 114         debug("AS3722 revision %#x found on I2C bus %s\n", revision, dev->name);
 115
 116         return 0;
 117 }
 118
 119 #if CONFIG_IS_ENABLED(PMIC_CHILDREN)
 120 static const struct pmic_child_info pmic_children_info[] = {
 121         { .prefix = "sd", .driver = "as3722_stepdown"},
 122         { .prefix = "ldo", .driver = "as3722_ldo"},
 123         { },
 124 };
 125
 126 static int as3722_bind(struct udevice *dev)
 127 {
 128         struct udevice *gpio_dev;
 129         ofnode regulators_node;
 130         int children;
 131         int ret;
 132
 133         regulators_node = dev_read_subnode(dev, "regulators");
 134         if (!ofnode_valid(regulators_node)) {
 135                 debug("%s: %s regulators subnode not found\n", __func__,
 136                       dev->name);
 137                 return -ENXIO;
 138         }
 139
 140         children = pmic_bind_children(dev, regulators_node, pmic_children_info);
 141         if (!children)
 142                 debug("%s: %s - no child found\n", __func__, dev->name);
 143         ret = device_bind_driver(dev, "gpio_as3722", "gpio_as3722", &gpio_dev);
 144         if (ret) {
 145                 debug("%s: Cannot bind GPIOs (ret=%d)\n", __func__, ret);
 146                 return ret;
 147         }
 148
 149         return 0;
 150 }
 151 #endif
 152
 153 static int as3722_reg_count(struct udevice *dev)
 154 {
 155         return AS3722_NUM_OF_REGS;
 156 }
 157
 158 static struct dm_pmic_ops as3722_ops = {
 159         .reg_count = as3722_reg_count,
 160         .read = as3722_read,
 161         .write = as3722_write,
 162 };
 163
 164 static const struct udevice_id as3722_ids[] = {
 165         { .compatible = "ams,as3722" },
 166         { }
 167 };
 168
 169 U_BOOT_DRIVER(pmic_as3722) = {
 170         .name = "as3722_pmic",
 171         .id = UCLASS_PMIC,
 172         .of_match = as3722_ids,
 173 #if CONFIG_IS_ENABLED(PMIC_CHILDREN)
 174         .bind = as3722_bind,
 175 #endif
 176         .probe = as3722_probe,
 177         .ops = &as3722_ops,
 178 };