Quelle  huawei-gaokun-battery.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * huawei-gaokun-battery - A power supply driver for HUAWEI Matebook E Go
 *
 * Copyright (C) 2024 Pengyu Luo <mitltlatltl@gmail.com>
 */

#include <linux/auxiliary_bus.h>
#include <linux/bits.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/platform_data/huawei-gaokun-ec.h>
#include <linux/power_supply.h>
#include <linux/sprintf.h>

/* -------------------------------------------------------------------------- */
/* String Data Reg */

#define EC_BAT_VENDOR  0x01 /* from 0x01 to 0x0F, SUNWODA */
#define EC_BAT_MODEL  0x11 /* from 0x11 to 0x1F, HB30A8P9ECW-22T */

#define EC_ADP_STATUS  0x81
#define EC_AC_STATUS  BIT(0)
#define EC_BAT_PRESENT  BIT(1) /* BATC._STA */

#define EC_BAT_STATUS  0x82 /* _BST */
#define EC_BAT_DISCHARGING BIT(0)
#define EC_BAT_CHARGING  BIT(1)
#define EC_BAT_CRITICAL  BIT(2) /* Low Battery Level */
#define EC_BAT_FULL  BIT(3)

/* -------------------------------------------------------------------------- */
/* Word Data Reg */

/* 0x5A: ?
 * 0x5C: ?
 * 0x5E: ?
 * 0X60: ?
 * 0x84: ?
 */

#define EC_BAT_STATUS_START 0x90
#define EC_BAT_PERCENTAGE 0x90
#define EC_BAT_VOLTAGE  0x92
#define EC_BAT_CAPACITY  0x94
#define EC_BAT_FULL_CAPACITY 0x96
/* 0x98: ? */
#define EC_BAT_CURRENT  0x9A
/* 0x9C: ? */

#define EC_BAT_INFO_START 0xA0
/* 0xA0: POWER_SUPPLY_PROP_INPUT_VOLTAGE_LIMIT? */
#define EC_BAT_DESIGN_CAPACITY 0xA2
#define EC_BAT_DESIGN_VOLTAGE 0xA4
#define EC_BAT_SERIAL_NUMBER 0xA6
#define EC_BAT_CYCLE_COUNT 0xAA

/* -------------------------------------------------------------------------- */
/* Battery Event ID */

#define EC_EVENT_BAT_A0  0xA0
#define EC_EVENT_BAT_A1  0xA1
#define EC_EVENT_BAT_A2  0xA2
#define EC_EVENT_BAT_A3  0xA3
#define EC_EVENT_BAT_B1  0xB1
/* EVENT B1 A0 A1 repeat about every 1s 2s 3s respectively */

/* ACPI _BIX field, Min sampling time, the duration between two _BST */
#define CACHE_TIME  2000 /* cache time in milliseconds */

#define MILLI_TO_MICRO  1000

#define SMART_CHARGE_MODE 0
#define SMART_CHARGE_DELAY 1
#define SMART_CHARGE_START 2
#define SMART_CHARGE_END 3

#define NO_DELAY_MODE 1
#define DELAY_MODE 4

struct gaokun_psy_bat_status {
 __le16 percentage_now; /* 0x90 */
 __le16 voltage_now;
 __le16 capacity_now;
 __le16 full_capacity;
 __le16 unknown1;
 __le16 rate_now;
 __le16 unknown2; /* 0x9C */
} __packed;

struct gaokun_psy_bat_info {
 __le16 unknown3; /* 0xA0 */
 __le16 design_capacity;
 __le16 design_voltage;
 __le16 serial_number;
 __le16 padding2;
 __le16 cycle_count; /* 0xAA */
} __packed;

struct gaokun_psy {
 struct gaokun_ec *ec;
 struct device *dev;
 struct notifier_block nb;

 struct power_supply *bat_psy;
 struct power_supply *adp_psy;

 unsigned long update_time;
 struct gaokun_psy_bat_status status;
 struct gaokun_psy_bat_info info;

 char battery_model[0x10]; /* HB30A8P9ECW-22T, the real one is XXX-22A */
 char battery_serial[0x10];
 char battery_vendor[0x10];

 int charge_now;
 int online;
 int bat_present;
};

/* -------------------------------------------------------------------------- */
/* Adapter */

static int gaokun_psy_get_adp_status(struct gaokun_psy *ecbat)
{
 /* _PSR */
 int ret;
 u8 online;

 ret = gaokun_ec_psy_read_byte(ecbat->ec, EC_ADP_STATUS, &online);
 if (ret)
  return ret;

 ecbat->online = !!(online & EC_AC_STATUS);

 return 0;
}

static int gaokun_psy_get_adp_property(struct power_supply *psy,
           enum power_supply_property psp,
           union power_supply_propval *val)
{
 struct gaokun_psy *ecbat = power_supply_get_drvdata(psy);
 int ret;

 ret = gaokun_psy_get_adp_status(ecbat);
 if (ret)
  return ret;

 switch (psp) {
 case POWER_SUPPLY_PROP_ONLINE:
  val->intval = ecbat->online;
  break;
 case POWER_SUPPLY_PROP_USB_TYPE:
  val->intval = POWER_SUPPLY_USB_TYPE_C;
  break;
 default:
  return -EINVAL;
 }

 return 0;
}

static enum power_supply_property gaokun_psy_adp_props[] = {
 POWER_SUPPLY_PROP_ONLINE,
 POWER_SUPPLY_PROP_USB_TYPE,
};

static const struct power_supply_desc gaokun_psy_adp_desc = {
 .name  = "gaokun-ec-adapter",
 .type  = POWER_SUPPLY_TYPE_USB,
 .usb_types = BIT(POWER_SUPPLY_USB_TYPE_C),
 .get_property = gaokun_psy_get_adp_property,
 .properties = gaokun_psy_adp_props,
 .num_properties = ARRAY_SIZE(gaokun_psy_adp_props),
};

/* -------------------------------------------------------------------------- */
/* Battery */

static inline void gaokun_psy_get_bat_present(struct gaokun_psy *ecbat)
{
 int ret;
 u8 present;

 /* Some kind of initialization */
 gaokun_ec_write(ecbat->ec, (u8 []){0x02, 0xB2, 1, 0x90});

 ret = gaokun_ec_psy_read_byte(ecbat->ec, EC_ADP_STATUS, &present);

 ecbat->bat_present = ret ? false : !!(present & EC_BAT_PRESENT);
}

static inline int gaokun_psy_bat_present(struct gaokun_psy *ecbat)
{
 return ecbat->bat_present;
}

static int gaokun_psy_get_bat_info(struct gaokun_psy *ecbat)
{
 /* _BIX */
 if (!gaokun_psy_bat_present(ecbat))
  return 0;

 return gaokun_ec_psy_multi_read(ecbat->ec, EC_BAT_INFO_START,
     sizeof(ecbat->info), (u8 *)&ecbat->info);
}

static void gaokun_psy_update_bat_charge(struct gaokun_psy *ecbat)
{
 u8 charge;

 gaokun_ec_psy_read_byte(ecbat->ec, EC_BAT_STATUS, &charge);

 switch (charge) {
 case EC_BAT_CHARGING:
  ecbat->charge_now = POWER_SUPPLY_STATUS_CHARGING;
  break;
 case EC_BAT_DISCHARGING:
  ecbat->charge_now = POWER_SUPPLY_STATUS_DISCHARGING;
  break;
 case EC_BAT_FULL:
  ecbat->charge_now = POWER_SUPPLY_STATUS_FULL;
  break;
 default:
  dev_warn(ecbat->dev, "unknown charge state %d\n", charge);
 }
}

static int gaokun_psy_get_bat_status(struct gaokun_psy *ecbat)
{
 /* _BST */
 int ret;

 if (time_before(jiffies, ecbat->update_time +
   msecs_to_jiffies(CACHE_TIME)))
  return 0;

 gaokun_psy_update_bat_charge(ecbat);
 ret = gaokun_ec_psy_multi_read(ecbat->ec, EC_BAT_STATUS_START,
           sizeof(ecbat->status), (u8 *)&ecbat->status);

 ecbat->update_time = jiffies;

 return ret;
}

static void gaokun_psy_init(struct gaokun_psy *ecbat)
{
 gaokun_psy_get_bat_present(ecbat);
 if (!gaokun_psy_bat_present(ecbat))
  return;

 gaokun_psy_get_bat_info(ecbat);

 snprintf(ecbat->battery_serial, sizeof(ecbat->battery_serial),
   "%d", le16_to_cpu(ecbat->info.serial_number));

 gaokun_ec_psy_multi_read(ecbat->ec, EC_BAT_VENDOR,
     sizeof(ecbat->battery_vendor) - 1,
     ecbat->battery_vendor);

 gaokun_ec_psy_multi_read(ecbat->ec, EC_BAT_MODEL,
     sizeof(ecbat->battery_model) - 1,
     ecbat->battery_model);

 ecbat->battery_model[14] = 'A'; /* FIX UP */
}

static int gaokun_psy_get_bat_property(struct power_supply *psy,
           enum power_supply_property psp,
           union power_supply_propval *val)
{
 struct gaokun_psy *ecbat = power_supply_get_drvdata(psy);
 u8 buf[GAOKUN_SMART_CHARGE_DATA_SIZE];
 int ret;

 if (gaokun_psy_bat_present(ecbat))
  gaokun_psy_get_bat_status(ecbat);
 else if (psp != POWER_SUPPLY_PROP_PRESENT)
  return -ENODEV;

 switch (psp) {
 case POWER_SUPPLY_PROP_STATUS:
  val->intval = ecbat->charge_now;
  break;

 case POWER_SUPPLY_PROP_PRESENT:
  val->intval = ecbat->bat_present;
  break;

 case POWER_SUPPLY_PROP_TECHNOLOGY:
  val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
  break;

 case POWER_SUPPLY_PROP_CYCLE_COUNT:
  val->intval = le16_to_cpu(ecbat->info.cycle_count);
  break;

 case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
  val->intval = le16_to_cpu(ecbat->info.design_voltage) * MILLI_TO_MICRO;
  break;

 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  val->intval = le16_to_cpu(ecbat->status.voltage_now) * MILLI_TO_MICRO;
  break;

 case POWER_SUPPLY_PROP_CURRENT_NOW:
  val->intval = (s16)le16_to_cpu(ecbat->status.rate_now) * MILLI_TO_MICRO;
  break;

 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
  val->intval = le16_to_cpu(ecbat->info.design_capacity) * MILLI_TO_MICRO;
  break;

 case POWER_SUPPLY_PROP_CHARGE_FULL:
  val->intval = le16_to_cpu(ecbat->status.full_capacity) * MILLI_TO_MICRO;
  break;

 case POWER_SUPPLY_PROP_CHARGE_NOW:
  val->intval = le16_to_cpu(ecbat->status.capacity_now) * MILLI_TO_MICRO;
  break;

 case POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD:
 case POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD:
  ret = gaokun_ec_psy_get_smart_charge(ecbat->ec, buf);
  if (ret)
   return ret;

  if (psp == POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD)
   val->intval = buf[SMART_CHARGE_START];
  else
   val->intval = buf[SMART_CHARGE_END];
  break;

 case POWER_SUPPLY_PROP_CAPACITY:
  val->intval = le16_to_cpu(ecbat->status.percentage_now);
  break;

 case POWER_SUPPLY_PROP_MODEL_NAME:
  val->strval = ecbat->battery_model;
  break;

 case POWER_SUPPLY_PROP_MANUFACTURER:
  val->strval = ecbat->battery_vendor;
  break;

 case POWER_SUPPLY_PROP_SERIAL_NUMBER:
  val->strval = ecbat->battery_serial;
  break;

 default:
  return -EINVAL;
 }

 return 0;
}

static int gaokun_psy_set_bat_property(struct power_supply *psy,
           enum power_supply_property psp,
           const union power_supply_propval *val)
{
 struct gaokun_psy *ecbat = power_supply_get_drvdata(psy);
 u8 buf[GAOKUN_SMART_CHARGE_DATA_SIZE];
 int ret;

 if (!gaokun_psy_bat_present(ecbat))
  return -ENODEV;

 ret = gaokun_ec_psy_get_smart_charge(ecbat->ec, buf);
 if (ret)
  return ret;

 switch (psp) {
 /*
 * Resetting another thershold makes single thersold setting more likely
 * to succeed. But setting start = end makes thing strange(failure).
 */
 case POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD:
  buf[SMART_CHARGE_START] = val->intval;
  if (buf[SMART_CHARGE_START] > buf[SMART_CHARGE_END])
   buf[SMART_CHARGE_END] = buf[SMART_CHARGE_START] + 1;
  return gaokun_ec_psy_set_smart_charge(ecbat->ec, buf);

 case POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD:
  buf[SMART_CHARGE_END] = val->intval;
  if (buf[SMART_CHARGE_END] < buf[SMART_CHARGE_START])
   buf[SMART_CHARGE_START] = buf[SMART_CHARGE_END] - 1;
  return gaokun_ec_psy_set_smart_charge(ecbat->ec, buf);

 default:
  return -EINVAL;
 }

 return 0;
}

static int gaokun_psy_is_bat_property_writeable(struct power_supply *psy,
      enum power_supply_property psp)
{
 return psp == POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD ||
        psp == POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD;
}

static enum power_supply_property gaokun_psy_bat_props[] = {
 POWER_SUPPLY_PROP_STATUS,
 POWER_SUPPLY_PROP_PRESENT,
 POWER_SUPPLY_PROP_TECHNOLOGY,
 POWER_SUPPLY_PROP_CYCLE_COUNT,
 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 POWER_SUPPLY_PROP_VOLTAGE_NOW,
 POWER_SUPPLY_PROP_CURRENT_NOW,
 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 POWER_SUPPLY_PROP_CHARGE_FULL,
 POWER_SUPPLY_PROP_CHARGE_NOW,
 POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD,
 POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD,
 POWER_SUPPLY_PROP_CAPACITY,
 POWER_SUPPLY_PROP_MODEL_NAME,
 POWER_SUPPLY_PROP_MANUFACTURER,
 POWER_SUPPLY_PROP_SERIAL_NUMBER,
};

static const struct power_supply_desc gaokun_psy_bat_desc = {
 .name   = "gaokun-ec-battery",
 .type   = POWER_SUPPLY_TYPE_BATTERY,
 .get_property  = gaokun_psy_get_bat_property,
 .set_property  = gaokun_psy_set_bat_property,
 .property_is_writeable = gaokun_psy_is_bat_property_writeable,
 .properties  = gaokun_psy_bat_props,
 .num_properties  = ARRAY_SIZE(gaokun_psy_bat_props),
};

/* -------------------------------------------------------------------------- */
/* Sysfs */

/*
 * Note that, HUAWEI calls them SBAC/GBAC and SBCM/GBCM in DSDT, they are likely
 * Set/Get Battery Adaptive Charging and Set/Get Battery Charging Mode.
 */

/* battery adaptive charge */
static ssize_t battery_adaptive_charge_show(struct device *dev,
         struct device_attribute *attr,
         char *buf)
{
 struct power_supply *psy = to_power_supply(dev);
 struct gaokun_psy *ecbat = power_supply_get_drvdata(psy);
 int ret;
 bool on;

 ret = gaokun_ec_psy_get_smart_charge_enable(ecbat->ec, &on);
 if (ret)
  return ret;

 return sysfs_emit(buf, "%d\n", on);
}

static ssize_t battery_adaptive_charge_store(struct device *dev,
          struct device_attribute *attr,
          const char *buf, size_t size)
{
 struct power_supply *psy = to_power_supply(dev);
 struct gaokun_psy *ecbat = power_supply_get_drvdata(psy);
 int ret;
 bool on;

 if (kstrtobool(buf, &on))
  return -EINVAL;

 ret = gaokun_ec_psy_set_smart_charge_enable(ecbat->ec, on);
 if (ret)
  return ret;

 return size;
}

static DEVICE_ATTR_RW(battery_adaptive_charge);

static inline int get_charge_delay(u8 buf[GAOKUN_SMART_CHARGE_DATA_SIZE])
{
 return buf[SMART_CHARGE_MODE] == NO_DELAY_MODE ? 0 : buf[SMART_CHARGE_DELAY];
}

static inline void
set_charge_delay(u8 buf[GAOKUN_SMART_CHARGE_DATA_SIZE], u8 delay)
{
 if (delay) {
  buf[SMART_CHARGE_DELAY] = delay;
  buf[SMART_CHARGE_MODE] = DELAY_MODE;
 } else {
   /* No writing zero, there is a specific mode for it. */
  buf[SMART_CHARGE_MODE] = NO_DELAY_MODE;
 }
}

/* Smart charge */
static ssize_t smart_charge_delay_show(struct device *dev,
           struct device_attribute *attr,
           char *buf)
{
 struct power_supply *psy = to_power_supply(dev);
 struct gaokun_psy *ecbat = power_supply_get_drvdata(psy);
 u8 bf[GAOKUN_SMART_CHARGE_DATA_SIZE];
 int ret;

 ret = gaokun_ec_psy_get_smart_charge(ecbat->ec, bf);
 if (ret)
  return ret;

 return sysfs_emit(buf, "%d\n", get_charge_delay(bf));
}

static ssize_t smart_charge_delay_store(struct device *dev,
     struct device_attribute *attr,
     const char *buf, size_t size)
{
 struct power_supply *psy = to_power_supply(dev);
 struct gaokun_psy *ecbat = power_supply_get_drvdata(psy);
 u8 bf[GAOKUN_SMART_CHARGE_DATA_SIZE];
 u8 delay;
 int ret;

 if (kstrtou8(buf, 10, &delay))
  return -EINVAL;

 ret = gaokun_ec_psy_get_smart_charge(ecbat->ec, bf);
 if (ret)
  return ret;

 set_charge_delay(bf, delay);

 ret = gaokun_ec_psy_set_smart_charge(ecbat->ec, bf);
 if (ret)
  return ret;

 return size;
}

static DEVICE_ATTR_RW(smart_charge_delay);

static struct attribute *gaokun_psy_features_attrs[] = {
 &dev_attr_battery_adaptive_charge.attr,
 &dev_attr_smart_charge_delay.attr,
 NULL,
};
ATTRIBUTE_GROUPS(gaokun_psy_features);

static int gaokun_psy_notify(struct notifier_block *nb,
        unsigned long action, void *data)
{
 struct gaokun_psy *ecbat = container_of(nb, struct gaokun_psy, nb);

 switch (action) {
 case EC_EVENT_BAT_A2:
 case EC_EVENT_BAT_B1:
  gaokun_psy_get_bat_info(ecbat);
  return NOTIFY_OK;

 case EC_EVENT_BAT_A0:
  gaokun_psy_get_adp_status(ecbat);
  power_supply_changed(ecbat->adp_psy);
  msleep(10);
  fallthrough;

 case EC_EVENT_BAT_A1:
 case EC_EVENT_BAT_A3:
  if (action == EC_EVENT_BAT_A3) {
   gaokun_psy_get_bat_info(ecbat);
   msleep(100);
  }
  gaokun_psy_get_bat_status(ecbat);
  power_supply_changed(ecbat->bat_psy);
  return NOTIFY_OK;

 default:
  return NOTIFY_DONE;
 }
}

static int gaokun_psy_probe(struct auxiliary_device *adev,
       const struct auxiliary_device_id *id)
{
 struct gaokun_ec *ec = adev->dev.platform_data;
 struct power_supply_config psy_cfg = {};
 struct device *dev = &adev->dev;
 struct gaokun_psy *ecbat;

 ecbat = devm_kzalloc(&adev->dev, sizeof(*ecbat), GFP_KERNEL);
 if (!ecbat)
  return -ENOMEM;

 ecbat->ec = ec;
 ecbat->dev = dev;
 ecbat->nb.notifier_call = gaokun_psy_notify;

 auxiliary_set_drvdata(adev, ecbat);

 psy_cfg.drv_data = ecbat;
 ecbat->adp_psy = devm_power_supply_register(dev, &gaokun_psy_adp_desc,
          &psy_cfg);
 if (IS_ERR(ecbat->adp_psy))
  return dev_err_probe(dev, PTR_ERR(ecbat->adp_psy),
         "Failed to register AC power supply\n");

 psy_cfg.supplied_to = (char **)&gaokun_psy_bat_desc.name;
 psy_cfg.num_supplicants = 1;
 psy_cfg.no_wakeup_source = true;
 psy_cfg.attr_grp = gaokun_psy_features_groups;
 ecbat->bat_psy = devm_power_supply_register(dev, &gaokun_psy_bat_desc,
          &psy_cfg);
 if (IS_ERR(ecbat->bat_psy))
  return dev_err_probe(dev, PTR_ERR(ecbat->bat_psy),
         "Failed to register battery power supply\n");
 gaokun_psy_init(ecbat);

 return gaokun_ec_register_notify(ec, &ecbat->nb);
}

static void gaokun_psy_remove(struct auxiliary_device *adev)
{
 struct gaokun_psy *ecbat = auxiliary_get_drvdata(adev);

 gaokun_ec_unregister_notify(ecbat->ec, &ecbat->nb);
}

static const struct auxiliary_device_id gaokun_psy_id_table[] = {
 { .name = GAOKUN_MOD_NAME "." GAOKUN_DEV_PSY, },
 {}
};
MODULE_DEVICE_TABLE(auxiliary, gaokun_psy_id_table);

static struct auxiliary_driver gaokun_psy_driver = {
 .name = GAOKUN_DEV_PSY,
 .id_table = gaokun_psy_id_table,
 .probe = gaokun_psy_probe,
 .remove = gaokun_psy_remove,
};

module_auxiliary_driver(gaokun_psy_driver);

MODULE_DESCRIPTION("HUAWEI Matebook E Go psy driver");
MODULE_LICENSE("GPL");