drivers/power/supply/max14656_charger_detector.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Maxim MAX14656 / AL32 USB Charger Detector driver
   4  *
   5  * Copyright (C) 2014 LG Electronics, Inc
   6  * Copyright (C) 2016 Alexander Kurz <akurz@blala.de>
   7  *
   8  * Components from Maxim AL32 Charger detection Driver for MX50 Yoshi Board
   9  * Copyright (C) Amazon Technologies Inc. All rights reserved.
  10  * Manish Lachwani (lachwani@lab126.com)
  11  */
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/delay.h>
  15 #include <linux/i2c.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/slab.h>
  18 #include <linux/gpio.h>
  19 #include <linux/of_gpio.h>
  20 #include <linux/of_device.h>
  21 #include <linux/workqueue.h>
  22 #include <linux/power_supply.h>
  23
  24 #define MAX14656_MANUFACTURER   "Maxim Integrated"
  25 #define MAX14656_NAME           "max14656"
  26
  27 #define MAX14656_DEVICE_ID      0x00
  28 #define MAX14656_INTERRUPT_1    0x01
  29 #define MAX14656_INTERRUPT_2    0x02
  30 #define MAX14656_STATUS_1       0x03
  31 #define MAX14656_STATUS_2       0x04
  32 #define MAX14656_INTMASK_1      0x05
  33 #define MAX14656_INTMASK_2      0x06
  34 #define MAX14656_CONTROL_1      0x07
  35 #define MAX14656_CONTROL_2      0x08
  36 #define MAX14656_CONTROL_3      0x09
  37
  38 #define DEVICE_VENDOR_MASK      0xf0
  39 #define DEVICE_REV_MASK         0x0f
  40 #define INT_EN_REG_MASK         BIT(4)
  41 #define CHG_TYPE_INT_MASK       BIT(0)
  42 #define STATUS1_VB_VALID_MASK   BIT(4)
  43 #define STATUS1_CHG_TYPE_MASK   0xf
  44 #define INT1_DCD_TIMEOUT_MASK   BIT(7)
  45 #define CONTROL1_DEFAULT        0x0d
  46 #define CONTROL1_INT_EN         BIT(4)
  47 #define CONTROL1_INT_ACTIVE_HIGH        BIT(5)
  48 #define CONTROL1_EDGE           BIT(7)
  49 #define CONTROL2_DEFAULT        0x8e
  50 #define CONTROL2_ADC_EN         BIT(0)
  51 #define CONTROL3_DEFAULT        0x8d
  52
  53 enum max14656_chg_type {
  54         MAX14656_NO_CHARGER     = 0,
  55         MAX14656_SDP_CHARGER,
  56         MAX14656_CDP_CHARGER,
  57         MAX14656_DCP_CHARGER,
  58         MAX14656_APPLE_500MA_CHARGER,
  59         MAX14656_APPLE_1A_CHARGER,
  60         MAX14656_APPLE_2A_CHARGER,
  61         MAX14656_SPECIAL_500MA_CHARGER,
  62         MAX14656_APPLE_12W,
  63         MAX14656_CHARGER_LAST
  64 };
  65
  66 static const struct max14656_chg_type_props {
  67         enum power_supply_type type;
  68 } chg_type_props[] = {
  69         { POWER_SUPPLY_TYPE_UNKNOWN },
  70         { POWER_SUPPLY_TYPE_USB },
  71         { POWER_SUPPLY_TYPE_USB_CDP },
  72         { POWER_SUPPLY_TYPE_USB_DCP },
  73         { POWER_SUPPLY_TYPE_USB_DCP },
  74         { POWER_SUPPLY_TYPE_USB_DCP },
  75         { POWER_SUPPLY_TYPE_USB_DCP },
  76         { POWER_SUPPLY_TYPE_USB_DCP },
  77         { POWER_SUPPLY_TYPE_USB },
  78 };
  79
  80 struct max14656_chip {
  81         struct i2c_client       *client;
  82         struct power_supply     *detect_psy;
  83         struct power_supply_desc psy_desc;
  84         struct delayed_work     irq_work;
  85
  86         int irq;
  87         int online;
  88 };
  89
  90 static int max14656_read_reg(struct i2c_client *client, int reg, u8 *val)
  91 {
  92         s32 ret;
  93
  94         ret = i2c_smbus_read_byte_data(client, reg);
  95         if (ret < 0) {
  96                 dev_err(&client->dev,
  97                         "i2c read fail: can't read from %02x: %d\n",
  98                         reg, ret);
  99                 return ret;
 100         }
 101         *val = ret;
 102         return 0;
 103 }
 104
 105 static int max14656_write_reg(struct i2c_client *client, int reg, u8 val)
 106 {
 107         s32 ret;
 108
 109         ret = i2c_smbus_write_byte_data(client, reg, val);
 110         if (ret < 0) {
 111                 dev_err(&client->dev,
 112                         "i2c write fail: can't write %02x to %02x: %d\n",
 113                         val, reg, ret);
 114                 return ret;
 115         }
 116         return 0;
 117 }
 118
 119 static int max14656_read_block_reg(struct i2c_client *client, u8 reg,
 120                                   u8 length, u8 *val)
 121 {
 122         int ret;
 123
 124         ret = i2c_smbus_read_i2c_block_data(client, reg, length, val);
 125         if (ret < 0) {
 126                 dev_err(&client->dev, "failed to block read reg 0x%x: %d\n",
 127                                 reg, ret);
 128                 return ret;
 129         }
 130
 131         return 0;
 132 }
 133
 134 #define        REG_TOTAL_NUM   5
 135 static void max14656_irq_worker(struct work_struct *work)
 136 {
 137         struct max14656_chip *chip =
 138                 container_of(work, struct max14656_chip, irq_work.work);
 139
 140         u8 buf[REG_TOTAL_NUM];
 141         u8 chg_type;
 142
 143         max14656_read_block_reg(chip->client, MAX14656_DEVICE_ID,
 144                                 REG_TOTAL_NUM, buf);
 145
 146         if ((buf[MAX14656_STATUS_1] & STATUS1_VB_VALID_MASK) &&
 147                 (buf[MAX14656_STATUS_1] & STATUS1_CHG_TYPE_MASK)) {
 148                 chg_type = buf[MAX14656_STATUS_1] & STATUS1_CHG_TYPE_MASK;
 149                 if (chg_type < MAX14656_CHARGER_LAST)
 150                         chip->psy_desc.type = chg_type_props[chg_type].type;
 151                 else
 152                         chip->psy_desc.type = POWER_SUPPLY_TYPE_UNKNOWN;
 153                 chip->online = 1;
 154         } else {
 155                 chip->online = 0;
 156                 chip->psy_desc.type = POWER_SUPPLY_TYPE_UNKNOWN;
 157         }
 158
 159         power_supply_changed(chip->detect_psy);
 160 }
 161
 162 static irqreturn_t max14656_irq(int irq, void *dev_id)
 163 {
 164         struct max14656_chip *chip = dev_id;
 165
 166         schedule_delayed_work(&chip->irq_work, msecs_to_jiffies(100));
 167
 168         return IRQ_HANDLED;
 169 }
 170
 171 static int max14656_hw_init(struct max14656_chip *chip)
 172 {
 173         uint8_t val = 0;
 174         uint8_t rev;
 175         struct i2c_client *client = chip->client;
 176
 177         if (max14656_read_reg(client, MAX14656_DEVICE_ID, &val))
 178                 return -ENODEV;
 179
 180         if ((val & DEVICE_VENDOR_MASK) != 0x20) {
 181                 dev_err(&client->dev, "wrong vendor ID %d\n",
 182                         ((val & DEVICE_VENDOR_MASK) >> 4));
 183                 return -ENODEV;
 184         }
 185         rev = val & DEVICE_REV_MASK;
 186
 187         /* Turn on ADC_EN */
 188         if (max14656_write_reg(client, MAX14656_CONTROL_2, CONTROL2_ADC_EN))
 189                 return -EINVAL;
 190
 191         /* turn on interrupts and low power mode */
 192         if (max14656_write_reg(client, MAX14656_CONTROL_1,
 193                 CONTROL1_DEFAULT |
 194                 CONTROL1_INT_EN |
 195                 CONTROL1_INT_ACTIVE_HIGH |
 196                 CONTROL1_EDGE))
 197                 return -EINVAL;
 198
 199         if (max14656_write_reg(client, MAX14656_INTMASK_1, 0x3))
 200                 return -EINVAL;
 201
 202         if (max14656_write_reg(client, MAX14656_INTMASK_2, 0x1))
 203                 return -EINVAL;
 204
 205         dev_info(&client->dev, "detected revision %d\n", rev);
 206         return 0;
 207 }
 208
 209 static int max14656_get_property(struct power_supply *psy,
 210                             enum power_supply_property psp,
 211                             union power_supply_propval *val)
 212 {
 213         struct max14656_chip *chip = power_supply_get_drvdata(psy);
 214
 215         switch (psp) {
 216         case POWER_SUPPLY_PROP_ONLINE:
 217                 val->intval = chip->online;
 218                 break;
 219         case POWER_SUPPLY_PROP_MODEL_NAME:
 220                 val->strval = MAX14656_NAME;
 221                 break;
 222         case POWER_SUPPLY_PROP_MANUFACTURER:
 223                 val->strval = MAX14656_MANUFACTURER;
 224                 break;
 225         default:
 226                 return -EINVAL;
 227         }
 228
 229         return 0;
 230 }
 231
 232 static enum power_supply_property max14656_battery_props[] = {
 233         POWER_SUPPLY_PROP_ONLINE,
 234         POWER_SUPPLY_PROP_MODEL_NAME,
 235         POWER_SUPPLY_PROP_MANUFACTURER,
 236 };
 237
 238 static void stop_irq_work(void *data)
 239 {
 240         struct max14656_chip *chip = data;
 241
 242         cancel_delayed_work_sync(&chip->irq_work);
 243 }
 244
 245
 246 static int max14656_probe(struct i2c_client *client,
 247                           const struct i2c_device_id *id)
 248 {
 249         struct i2c_adapter *adapter = client->adapter;
 250         struct device *dev = &client->dev;
 251         struct power_supply_config psy_cfg = {};
 252         struct max14656_chip *chip;
 253         int irq = client->irq;
 254         int ret = 0;
 255
 256         if (irq <= 0) {
 257                 dev_err(dev, "invalid irq number: %d\n", irq);
 258                 return -ENODEV;
 259         }
 260
 261         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
 262                 dev_err(dev, "No support for SMBUS_BYTE_DATA\n");
 263                 return -ENODEV;
 264         }
 265
 266         chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 267         if (!chip)
 268                 return -ENOMEM;
 269
 270         psy_cfg.drv_data = chip;
 271         chip->client = client;
 272         chip->online = 0;
 273         chip->psy_desc.name = MAX14656_NAME;
 274         chip->psy_desc.type = POWER_SUPPLY_TYPE_UNKNOWN;
 275         chip->psy_desc.properties = max14656_battery_props;
 276         chip->psy_desc.num_properties = ARRAY_SIZE(max14656_battery_props);
 277         chip->psy_desc.get_property = max14656_get_property;
 278         chip->irq = irq;
 279
 280         ret = max14656_hw_init(chip);
 281         if (ret)
 282                 return -ENODEV;
 283
 284         chip->detect_psy = devm_power_supply_register(dev,
 285                        &chip->psy_desc, &psy_cfg);
 286         if (IS_ERR(chip->detect_psy)) {
 287                 dev_err(dev, "power_supply_register failed\n");
 288                 return -EINVAL;
 289         }
 290
 291         INIT_DELAYED_WORK(&chip->irq_work, max14656_irq_worker);
 292         ret = devm_add_action(dev, stop_irq_work, chip);
 293         if (ret) {
 294                 dev_err(dev, "devm_add_action %d failed\n", ret);
 295                 return ret;
 296         }
 297
 298         ret = devm_request_irq(dev, chip->irq, max14656_irq,
 299                                IRQF_TRIGGER_FALLING,
 300                                MAX14656_NAME, chip);
 301         if (ret) {
 302                 dev_err(dev, "request_irq %d failed\n", chip->irq);
 303                 return -EINVAL;
 304         }
 305         enable_irq_wake(chip->irq);
 306
 307         schedule_delayed_work(&chip->irq_work, msecs_to_jiffies(2000));
 308
 309         return 0;
 310 }
 311
 312 static const struct i2c_device_id max14656_id[] = {
 313         { "max14656", 0 },
 314         {}
 315 };
 316 MODULE_DEVICE_TABLE(i2c, max14656_id);
 317
 318 static const struct of_device_id max14656_match_table[] = {
 319         { .compatible = "maxim,max14656", },
 320         {}
 321 };
 322 MODULE_DEVICE_TABLE(of, max14656_match_table);
 323
 324 static struct i2c_driver max14656_i2c_driver = {
 325         .driver = {
 326                 .name   = "max14656",
 327                 .of_match_table = max14656_match_table,
 328         },
 329         .probe          = max14656_probe,
 330         .id_table       = max14656_id,
 331 };
 332 module_i2c_driver(max14656_i2c_driver);
 333
 334 MODULE_DESCRIPTION("MAX14656 USB charger detector");
 335 MODULE_LICENSE("GPL v2");