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