--- /dev/null
+/*
+ * 1-Wire implementation for Maxim Semiconductor
+ * MAX7211/MAX17215 stanalone fuel gauge chip
+ *
+ * Copyright (C) 2017 Radioavionica Corporation
+ * Author: Alex A. Mihaylov <minimumlaw@rambler.ru>
+ *
+ * Use consistent with the GNU GPL is permitted,
+ * provided that this copyright notice is
+ * preserved in its entirety in all copies and derived works.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/w1.h>
+#include <linux/regmap.h>
+#include <linux/power_supply.h>
+
+#define W1_MAX1721X_FAMILY_ID 0x26
+#define DEF_DEV_NAME_MAX17211 "MAX17211"
+#define DEF_DEV_NAME_MAX17215 "MAX17215"
+#define DEF_DEV_NAME_UNKNOWN "UNKNOWN"
+#define DEF_MFG_NAME "MAXIM"
+
+#define PSY_MAX_NAME_LEN 32
+
+/* Number of valid register addresses in W1 mode */
+#define MAX1721X_MAX_REG_NR 0x1EF
+
+/* Factory settings (nonvilatile registers) (W1 specific) */
+#define MAX1721X_REG_NRSENSE 0x1CF /* RSense in 10^-5 Ohm */
+/* Strings */
+#define MAX1721X_REG_MFG_STR 0x1CC
+#define MAX1721X_REG_MFG_NUMB 3
+#define MAX1721X_REG_DEV_STR 0x1DB
+#define MAX1721X_REG_DEV_NUMB 5
+/* HEX Strings */
+#define MAX1721X_REG_SER_HEX 0x1D8
+
+/* MAX172XX Output Registers for W1 chips */
+#define MAX172XX_REG_STATUS 0x000 /* status reg */
+#define MAX172XX_BAT_PRESENT (1<<4) /* battery connected bit */
+#define MAX172XX_REG_DEVNAME 0x021 /* chip config */
+#define MAX172XX_DEV_MASK 0x000F /* chip type mask */
+#define MAX172X1_DEV 0x0001
+#define MAX172X5_DEV 0x0005
+#define MAX172XX_REG_TEMP 0x008 /* Temperature */
+#define MAX172XX_REG_BATT 0x0DA /* Battery voltage */
+#define MAX172XX_REG_CURRENT 0x00A /* Actual current */
+#define MAX172XX_REG_AVGCURRENT 0x00B /* Average current */
+#define MAX172XX_REG_REPSOC 0x006 /* Percentage of charge */
+#define MAX172XX_REG_DESIGNCAP 0x018 /* Design capacity */
+#define MAX172XX_REG_REPCAP 0x005 /* Average capacity */
+#define MAX172XX_REG_TTE 0x011 /* Time to empty */
+#define MAX172XX_REG_TTF 0x020 /* Time to full */
+
+struct max17211_device_info {
+ char name[PSY_MAX_NAME_LEN];
+ struct power_supply *bat;
+ struct power_supply_desc bat_desc;
+ struct device *w1_dev;
+ struct regmap *regmap;
+ /* battery design format */
+ unsigned int rsense; /* in tenths uOhm */
+ char DeviceName[2 * MAX1721X_REG_DEV_NUMB + 1];
+ char ManufacturerName[2 * MAX1721X_REG_MFG_NUMB + 1];
+ char SerialNumber[13]; /* see get_sn_str() later for comment */
+};
+
+/* Convert regs value to power_supply units */
+
+static inline int max172xx_time_to_ps(unsigned int reg)
+{
+ return reg * 5625 / 1000; /* in sec. */
+}
+
+static inline int max172xx_percent_to_ps(unsigned int reg)
+{
+ return reg / 256; /* in percent from 0 to 100 */
+}
+
+static inline int max172xx_voltage_to_ps(unsigned int reg)
+{
+ return reg * 1250; /* in uV */
+}
+
+static inline int max172xx_capacity_to_ps(unsigned int reg)
+{
+ return reg * 500; /* in uAh */
+}
+
+/*
+ * Current and temperature is signed values, so unsigned regs
+ * value must be converted to signed type
+ */
+
+static inline int max172xx_temperature_to_ps(unsigned int reg)
+{
+ int val = (int16_t)(reg);
+
+ return val * 10 / 256; /* in tenths of deg. C */
+}
+
+/*
+ * Calculating current registers resolution:
+ *
+ * RSense stored in 10^-5 Ohm, so mesaurment voltage must be
+ * in 10^-11 Volts for get current in uA.
+ * 16 bit current reg fullscale +/-51.2mV is 102400 uV.
+ * So: 102400 / 65535 * 10^5 = 156252
+ */
+static inline int max172xx_current_to_voltage(unsigned int reg)
+{
+ int val = (int16_t)(reg);
+
+ return val * 156252;
+}
+
+
+static inline struct max17211_device_info *
+to_device_info(struct power_supply *psy)
+{
+ return power_supply_get_drvdata(psy);
+}
+
+static int max1721x_battery_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct max17211_device_info *info = to_device_info(psy);
+ unsigned int reg = 0;
+ int ret = 0;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_PRESENT:
+ /*
+ * POWER_SUPPLY_PROP_PRESENT will always readable via
+ * sysfs interface. Value return 0 if battery not
+ * present or unaccesable via W1.
+ */
+ val->intval =
+ regmap_read(info->regmap, MAX172XX_REG_STATUS,
+ ®) ? 0 : !(reg & MAX172XX_BAT_PRESENT);
+ break;
+ case POWER_SUPPLY_PROP_CAPACITY:
+ ret = regmap_read(info->regmap, MAX172XX_REG_REPSOC, ®);
+ val->intval = max172xx_percent_to_ps(reg);
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ ret = regmap_read(info->regmap, MAX172XX_REG_BATT, ®);
+ val->intval = max172xx_voltage_to_ps(reg);
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+ ret = regmap_read(info->regmap, MAX172XX_REG_DESIGNCAP, ®);
+ val->intval = max172xx_capacity_to_ps(reg);
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_AVG:
+ ret = regmap_read(info->regmap, MAX172XX_REG_REPCAP, ®);
+ val->intval = max172xx_capacity_to_ps(reg);
+ break;
+ case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
+ ret = regmap_read(info->regmap, MAX172XX_REG_TTE, ®);
+ val->intval = max172xx_time_to_ps(reg);
+ break;
+ case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
+ ret = regmap_read(info->regmap, MAX172XX_REG_TTF, ®);
+ val->intval = max172xx_time_to_ps(reg);
+ break;
+ case POWER_SUPPLY_PROP_TEMP:
+ ret = regmap_read(info->regmap, MAX172XX_REG_TEMP, ®);
+ val->intval = max172xx_temperature_to_ps(reg);
+ break;
+ /* We need signed current, so must cast info->rsense to signed type */
+ case POWER_SUPPLY_PROP_CURRENT_NOW:
+ ret = regmap_read(info->regmap, MAX172XX_REG_CURRENT, ®);
+ val->intval =
+ max172xx_current_to_voltage(reg) / (int)info->rsense;
+ break;
+ case POWER_SUPPLY_PROP_CURRENT_AVG:
+ ret = regmap_read(info->regmap, MAX172XX_REG_AVGCURRENT, ®);
+ val->intval =
+ max172xx_current_to_voltage(reg) / (int)info->rsense;
+ break;
+ /*
+ * Strings already received and inited by probe.
+ * We do dummy read for check battery still available.
+ */
+ case POWER_SUPPLY_PROP_MODEL_NAME:
+ ret = regmap_read(info->regmap, MAX1721X_REG_DEV_STR, ®);
+ val->strval = info->DeviceName;
+ break;
+ case POWER_SUPPLY_PROP_MANUFACTURER:
+ ret = regmap_read(info->regmap, MAX1721X_REG_MFG_STR, ®);
+ val->strval = info->ManufacturerName;
+ break;
+ case POWER_SUPPLY_PROP_SERIAL_NUMBER:
+ ret = regmap_read(info->regmap, MAX1721X_REG_SER_HEX, ®);
+ val->strval = info->SerialNumber;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static enum power_supply_property max1721x_battery_props[] = {
+ /* int */
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+ POWER_SUPPLY_PROP_CHARGE_AVG,
+ POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
+ POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
+ POWER_SUPPLY_PROP_TEMP,
+ POWER_SUPPLY_PROP_CURRENT_NOW,
+ POWER_SUPPLY_PROP_CURRENT_AVG,
+ /* strings */
+ POWER_SUPPLY_PROP_MODEL_NAME,
+ POWER_SUPPLY_PROP_MANUFACTURER,
+ POWER_SUPPLY_PROP_SERIAL_NUMBER,
+};
+
+static int get_string(struct max17211_device_info *info,
+ uint16_t reg, uint8_t nr, char *str)
+{
+ unsigned int val;
+
+ if (!str || !(reg == MAX1721X_REG_MFG_STR ||
+ reg == MAX1721X_REG_DEV_STR))
+ return -EFAULT;
+
+ while (nr--) {
+ if (regmap_read(info->regmap, reg++, &val))
+ return -EFAULT;
+ *str++ = val>>8 & 0x00FF;
+ *str++ = val & 0x00FF;
+ }
+ return 0;
+}
+
+/* Maxim say: Serial number is a hex string up to 12 hex characters */
+static int get_sn_string(struct max17211_device_info *info, char *str)
+{
+ unsigned int val[3];
+
+ if (!str)
+ return -EFAULT;
+
+ if (regmap_read(info->regmap, MAX1721X_REG_SER_HEX, &val[0]))
+ return -EFAULT;
+ if (regmap_read(info->regmap, MAX1721X_REG_SER_HEX + 1, &val[1]))
+ return -EFAULT;
+ if (regmap_read(info->regmap, MAX1721X_REG_SER_HEX + 2, &val[2]))
+ return -EFAULT;
+
+ snprintf(str, 13, "%04X%04X%04X", val[0], val[1], val[2]);
+ return 0;
+}
+
+/*
+ * MAX1721x registers description for w1-regmap
+ */
+static const struct regmap_range max1721x_allow_range[] = {
+ regmap_reg_range(0, 0xDF), /* volatile data */
+ regmap_reg_range(0x180, 0x1DF), /* non-volatile memory */
+ regmap_reg_range(0x1E0, 0x1EF), /* non-volatile history (unused) */
+};
+
+static const struct regmap_range max1721x_deny_range[] = {
+ /* volatile data unused registers */
+ regmap_reg_range(0x24, 0x26),
+ regmap_reg_range(0x30, 0x31),
+ regmap_reg_range(0x33, 0x34),
+ regmap_reg_range(0x37, 0x37),
+ regmap_reg_range(0x3B, 0x3C),
+ regmap_reg_range(0x40, 0x41),
+ regmap_reg_range(0x43, 0x44),
+ regmap_reg_range(0x47, 0x49),
+ regmap_reg_range(0x4B, 0x4C),
+ regmap_reg_range(0x4E, 0xAF),
+ regmap_reg_range(0xB1, 0xB3),
+ regmap_reg_range(0xB5, 0xB7),
+ regmap_reg_range(0xBF, 0xD0),
+ regmap_reg_range(0xDB, 0xDB),
+ /* hole between volatile and non-volatile registers */
+ regmap_reg_range(0xE0, 0x17F),
+};
+
+static const struct regmap_access_table max1721x_regs = {
+ .yes_ranges = max1721x_allow_range,
+ .n_yes_ranges = ARRAY_SIZE(max1721x_allow_range),
+ .no_ranges = max1721x_deny_range,
+ .n_no_ranges = ARRAY_SIZE(max1721x_deny_range),
+};
+
+/*
+ * Model Gauge M5 Algorithm output register
+ * Volatile data (must not be cached)
+ */
+static const struct regmap_range max1721x_volatile_allow[] = {
+ regmap_reg_range(0, 0xDF),
+};
+
+static const struct regmap_access_table max1721x_volatile_regs = {
+ .yes_ranges = max1721x_volatile_allow,
+ .n_yes_ranges = ARRAY_SIZE(max1721x_volatile_allow),
+};
+
+/*
+ * W1-regmap config
+ */
+static const struct regmap_config max1721x_regmap_w1_config = {
+ .reg_bits = 16,
+ .val_bits = 16,
+ .rd_table = &max1721x_regs,
+ .volatile_table = &max1721x_volatile_regs,
+ .max_register = MAX1721X_MAX_REG_NR,
+};
+
+static int devm_w1_max1721x_add_device(struct w1_slave *sl)
+{
+ struct power_supply_config psy_cfg = {};
+ struct max17211_device_info *info;
+
+ info = devm_kzalloc(&sl->dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ sl->family_data = (void *)info;
+ info->w1_dev = &sl->dev;
+
+ /*
+ * power_supply class battery name translated from W1 slave device
+ * unical ID (look like 26-0123456789AB) to "max1721x-0123456789AB\0"
+ * so, 26 (device family) correcpondent to max1721x devices.
+ * Device name still unical for any numbers connected devices.
+ */
+ snprintf(info->name, sizeof(info->name),
+ "max1721x-%012X", (unsigned int)sl->reg_num.id);
+ info->bat_desc.name = info->name;
+
+ /*
+ * FixMe: battery device name exceed max len for thermal_zone device
+ * name and translation to thermal_zone must be disabled.
+ */
+ info->bat_desc.no_thermal = true;
+ info->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+ info->bat_desc.properties = max1721x_battery_props;
+ info->bat_desc.num_properties = ARRAY_SIZE(max1721x_battery_props);
+ info->bat_desc.get_property = max1721x_battery_get_property;
+ psy_cfg.drv_data = info;
+
+ /* regmap init */
+ info->regmap = devm_regmap_init_w1(info->w1_dev,
+ &max1721x_regmap_w1_config);
+ if (IS_ERR(info->regmap)) {
+ int err = PTR_ERR(info->regmap);
+
+ dev_err(info->w1_dev, "Failed to allocate register map: %d\n",
+ err);
+ return err;
+ }
+
+ /* rsense init */
+ info->rsense = 0;
+ if (regmap_read(info->regmap, MAX1721X_REG_NRSENSE, &info->rsense)) {
+ dev_err(info->w1_dev, "Can't read RSense. Hardware error.\n");
+ return -ENODEV;
+ }
+
+ if (!info->rsense) {
+ dev_warn(info->w1_dev, "RSenese not calibrated, set 10 mOhms!\n");
+ info->rsense = 1000; /* in regs in 10^-5 */
+ }
+ dev_info(info->w1_dev, "RSense: %d mOhms.\n", info->rsense / 100);
+
+ if (get_string(info, MAX1721X_REG_MFG_STR,
+ MAX1721X_REG_MFG_NUMB, info->ManufacturerName)) {
+ dev_err(info->w1_dev, "Can't read manufacturer. Hardware error.\n");
+ return -ENODEV;
+ }
+
+ if (!info->ManufacturerName[0])
+ strncpy(info->ManufacturerName, DEF_MFG_NAME,
+ 2 * MAX1721X_REG_MFG_NUMB);
+
+ if (get_string(info, MAX1721X_REG_DEV_STR,
+ MAX1721X_REG_DEV_NUMB, info->DeviceName)) {
+ dev_err(info->w1_dev, "Can't read device. Hardware error.\n");
+ return -ENODEV;
+ }
+ if (!info->DeviceName[0]) {
+ unsigned int dev_name;
+
+ if (regmap_read(info->regmap,
+ MAX172XX_REG_DEVNAME, &dev_name)) {
+ dev_err(info->w1_dev, "Can't read device name reg.\n");
+ return -ENODEV;
+ }
+
+ switch (dev_name & MAX172XX_DEV_MASK) {
+ case MAX172X1_DEV:
+ strncpy(info->DeviceName, DEF_DEV_NAME_MAX17211,
+ 2 * MAX1721X_REG_DEV_NUMB);
+ break;
+ case MAX172X5_DEV:
+ strncpy(info->DeviceName, DEF_DEV_NAME_MAX17215,
+ 2 * MAX1721X_REG_DEV_NUMB);
+ break;
+ default:
+ strncpy(info->DeviceName, DEF_DEV_NAME_UNKNOWN,
+ 2 * MAX1721X_REG_DEV_NUMB);
+ }
+ }
+
+ if (get_sn_string(info, info->SerialNumber)) {
+ dev_err(info->w1_dev, "Can't read serial. Hardware error.\n");
+ return -ENODEV;
+ }
+
+ info->bat = devm_power_supply_register(&sl->dev, &info->bat_desc,
+ &psy_cfg);
+ if (IS_ERR(info->bat)) {
+ dev_err(info->w1_dev, "failed to register battery\n");
+ return PTR_ERR(info->bat);
+ }
+
+ return 0;
+}
+
+static struct w1_family_ops w1_max1721x_fops = {
+ .add_slave = devm_w1_max1721x_add_device,
+};
+
+static struct w1_family w1_max1721x_family = {
+ .fid = W1_MAX1721X_FAMILY_ID,
+ .fops = &w1_max1721x_fops,
+};
+
+module_w1_family(w1_max1721x_family);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alex A. Mihaylov <minimumlaw@rambler.ru>");
+MODULE_DESCRIPTION("Maxim MAX17211/MAX17215 Fuel Gauage IC driver");
+MODULE_ALIAS("w1-family-" __stringify(W1_MAX1721X_FAMILY_ID));
projects / platform / kernel / linux-rpi.git / commitdiff