1 // SPDX-License-Identifier: GPL-2.0-only
3 * Maxim MAX14656 / AL32 USB Charger Detector driver
5 * Copyright (C) 2014 LG Electronics, Inc
6 * Copyright (C) 2016 Alexander Kurz <akurz@blala.de>
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)
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/of_device.h>
19 #include <linux/workqueue.h>
20 #include <linux/power_supply.h>
21 #include <linux/devm-helpers.h>
23 #define MAX14656_MANUFACTURER "Maxim Integrated"
24 #define MAX14656_NAME "max14656"
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
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
52 enum max14656_chg_type {
53 MAX14656_NO_CHARGER = 0,
57 MAX14656_APPLE_500MA_CHARGER,
58 MAX14656_APPLE_1A_CHARGER,
59 MAX14656_APPLE_2A_CHARGER,
60 MAX14656_SPECIAL_500MA_CHARGER,
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 },
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;
89 static int max14656_read_reg(struct i2c_client *client, int reg, u8 *val)
93 ret = i2c_smbus_read_byte_data(client, reg);
96 "i2c read fail: can't read from %02x: %d\n",
104 static int max14656_write_reg(struct i2c_client *client, int reg, u8 val)
108 ret = i2c_smbus_write_byte_data(client, reg, val);
110 dev_err(&client->dev,
111 "i2c write fail: can't write %02x to %02x: %d\n",
118 static int max14656_read_block_reg(struct i2c_client *client, u8 reg,
123 ret = i2c_smbus_read_i2c_block_data(client, reg, length, val);
125 dev_err(&client->dev, "failed to block read reg 0x%x: %d\n",
133 #define REG_TOTAL_NUM 5
134 static void max14656_irq_worker(struct work_struct *work)
136 struct max14656_chip *chip =
137 container_of(work, struct max14656_chip, irq_work.work);
139 u8 buf[REG_TOTAL_NUM];
142 max14656_read_block_reg(chip->client, MAX14656_DEVICE_ID,
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;
151 chip->psy_desc.type = POWER_SUPPLY_TYPE_UNKNOWN;
155 chip->psy_desc.type = POWER_SUPPLY_TYPE_UNKNOWN;
158 power_supply_changed(chip->detect_psy);
161 static irqreturn_t max14656_irq(int irq, void *dev_id)
163 struct max14656_chip *chip = dev_id;
165 schedule_delayed_work(&chip->irq_work, msecs_to_jiffies(100));
170 static int max14656_hw_init(struct max14656_chip *chip)
174 struct i2c_client *client = chip->client;
176 if (max14656_read_reg(client, MAX14656_DEVICE_ID, &val))
179 if ((val & DEVICE_VENDOR_MASK) != 0x20) {
180 dev_err(&client->dev, "wrong vendor ID %d\n",
181 ((val & DEVICE_VENDOR_MASK) >> 4));
184 rev = val & DEVICE_REV_MASK;
187 if (max14656_write_reg(client, MAX14656_CONTROL_2, CONTROL2_ADC_EN))
190 /* turn on interrupts and low power mode */
191 if (max14656_write_reg(client, MAX14656_CONTROL_1,
194 CONTROL1_INT_ACTIVE_HIGH |
198 if (max14656_write_reg(client, MAX14656_INTMASK_1, 0x3))
201 if (max14656_write_reg(client, MAX14656_INTMASK_2, 0x1))
204 dev_info(&client->dev, "detected revision %d\n", rev);
208 static int max14656_get_property(struct power_supply *psy,
209 enum power_supply_property psp,
210 union power_supply_propval *val)
212 struct max14656_chip *chip = power_supply_get_drvdata(psy);
215 case POWER_SUPPLY_PROP_ONLINE:
216 val->intval = chip->online;
218 case POWER_SUPPLY_PROP_MODEL_NAME:
219 val->strval = MAX14656_NAME;
221 case POWER_SUPPLY_PROP_MANUFACTURER:
222 val->strval = MAX14656_MANUFACTURER;
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,
237 static int max14656_probe(struct i2c_client *client)
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;
247 dev_err(dev, "invalid irq number: %d\n", irq);
251 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
252 dev_err(dev, "No support for SMBUS_BYTE_DATA\n");
256 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
260 psy_cfg.drv_data = chip;
261 chip->client = client;
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;
270 ret = max14656_hw_init(chip);
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");
281 ret = devm_delayed_work_autocancel(dev, &chip->irq_work,
282 max14656_irq_worker);
284 dev_err(dev, "devm_delayed_work_autocancel %d failed\n", ret);
288 ret = devm_request_irq(dev, chip->irq, max14656_irq,
289 IRQF_TRIGGER_FALLING,
290 MAX14656_NAME, chip);
292 dev_err(dev, "request_irq %d failed\n", chip->irq);
295 enable_irq_wake(chip->irq);
297 schedule_delayed_work(&chip->irq_work, msecs_to_jiffies(2000));
302 static const struct i2c_device_id max14656_id[] = {
306 MODULE_DEVICE_TABLE(i2c, max14656_id);
308 static const struct of_device_id max14656_match_table[] = {
309 { .compatible = "maxim,max14656", },
312 MODULE_DEVICE_TABLE(of, max14656_match_table);
314 static struct i2c_driver max14656_i2c_driver = {
317 .of_match_table = max14656_match_table,
319 .probe_new = max14656_probe,
320 .id_table = max14656_id,
322 module_i2c_driver(max14656_i2c_driver);
324 MODULE_DESCRIPTION("MAX14656 USB charger detector");
325 MODULE_LICENSE("GPL v2");