[PATCH v4 2/5] power: supply: ug3105_battery: Switch to adc-battery-helper

[Hans de Goede <hansg@kernel.org>]

Switch ug3105_battery to using the new adc-battery-helper, since the
helper's algorithms are a copy of the replaced ug3105_battery code
this should not cause any functional differences.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans de Goede <hansg@kernel.org>
---
Changes in v3:
- Rebase on latest upstream ug3105_battery.c
---
 drivers/power/supply/Kconfig          |   1 +
 drivers/power/supply/ug3105_battery.c | 344 +++++---------------------
 2 files changed, 65 insertions(+), 280 deletions(-)

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 8cfaded2cc5c..e33a5360d33a 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -1046,6 +1046,7 @@ config CHARGER_SURFACE
 config BATTERY_UG3105
 	tristate "uPI uG3105 battery monitor driver"
 	depends on I2C
+	select ADC_BATTERY_HELPER
 	help
 	  Battery monitor driver for the uPI uG3105 battery monitor.
 
diff --git a/drivers/power/supply/ug3105_battery.c b/drivers/power/supply/ug3105_battery.c
index e8a1de7cade0..70dd58e121e3 100644
--- a/drivers/power/supply/ug3105_battery.c
+++ b/drivers/power/supply/ug3105_battery.c
@@ -10,7 +10,22 @@
  * is off or suspended, the coulomb counter is not used atm.
  *
  * Possible improvements:
- * 1. Activate commented out total_coulomb_count code
+ * 1. Add coulumb counter reading, e.g. something like this:
+ * Read + reset coulomb counter every 10 polls (every 300 seconds)
+ *
+ * if ((chip->poll_count % 10) == 0) {
+ *	val = ug3105_read_word(chip->client, UG3105_REG_COULOMB_CNT);
+ *	if (val < 0)
+ *		goto out;
+ *
+ *	i2c_smbus_write_byte_data(chip->client, UG3105_REG_CTRL1,
+ *				  UG3105_CTRL1_RESET_COULOMB_CNT);
+ *
+ *	chip->total_coulomb_count += (s16)val;
+ *	dev_dbg(&chip->client->dev, "coulomb count %d total %d\n",
+ *		(s16)val, chip->total_coulomb_count);
+ * }
+ *
  * 2. Reset total_coulomb_count val to 0 when the battery is as good as empty
  *    and remember that we did this (and clear the flag for this on susp/resume)
  * 3. When the battery is full check if the flag that we set total_coulomb_count
@@ -31,24 +46,16 @@
  * has shown that an estimated 7404mWh increase of the battery's energy results
  * in a total_coulomb_count increase of 3277 units with a 5 milli-ohm sense R.
  *
- * Copyright (C) 2021 Hans de Goede <hdegoede@redhat.com>
+ * Copyright (C) 2021 - 2025 Hans de Goede <hansg@kernel.org>
  */
 
-#include <linux/devm-helpers.h>
 #include <linux/module.h>
-#include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/mod_devicetable.h>
 #include <linux/power_supply.h>
-#include <linux/workqueue.h>
 
-#define UG3105_MOV_AVG_WINDOW					8
-#define UG3105_INIT_POLL_TIME					(5 * HZ)
-#define UG3105_POLL_TIME					(30 * HZ)
-#define UG3105_SETTLE_TIME					(1 * HZ)
-
-#define UG3105_INIT_POLL_COUNT					30
+#include "adc-battery-helper.h"
 
 #define UG3105_REG_MODE						0x00
 #define UG3105_REG_CTRL1					0x01
@@ -61,34 +68,13 @@
 
 #define UG3105_CTRL1_RESET_COULOMB_CNT				0x03
 
-#define UG3105_CURR_HYST_UA					65000
-
-#define UG3105_LOW_BAT_UV					3700000
-#define UG3105_FULL_BAT_HYST_UV					38000
-
-#define AMBIENT_TEMP_CELCIUS					25
-
 struct ug3105_chip {
+	/* Must be the first member see adc-battery-helper documentation */
+	struct adc_battery_helper helper;
 	struct i2c_client *client;
 	struct power_supply *psy;
-	struct delayed_work work;
-	struct mutex lock;
-	int ocv[UG3105_MOV_AVG_WINDOW];		/* micro-volt */
-	int intern_res[UG3105_MOV_AVG_WINDOW];	/* milli-ohm */
-	int poll_count;
-	int ocv_avg_index;
-	int ocv_avg;				/* micro-volt */
-	int intern_res_poll_count;
-	int intern_res_avg_index;
-	int intern_res_avg;			/* milli-ohm */
-	int volt;				/* micro-volt */
-	int curr;				/* micro-ampere */
-	int total_coulomb_count;
 	int uv_per_unit;
 	int ua_per_unit;
-	int status;
-	int capacity;
-	bool supplied;
 };
 
 static int ug3105_read_word(struct i2c_client *client, u8 reg)
@@ -102,230 +88,43 @@ static int ug3105_read_word(struct i2c_client *client, u8 reg)
 	return val;
 }
 
-static int ug3105_get_status(struct ug3105_chip *chip)
-{
-	int full = chip->psy->battery_info->constant_charge_voltage_max_uv -
-		   UG3105_FULL_BAT_HYST_UV;
-
-	if (chip->curr > UG3105_CURR_HYST_UA)
-		return POWER_SUPPLY_STATUS_CHARGING;
-
-	if (chip->curr < -UG3105_CURR_HYST_UA)
-		return POWER_SUPPLY_STATUS_DISCHARGING;
-
-	if (chip->supplied && chip->ocv_avg > full)
-		return POWER_SUPPLY_STATUS_FULL;
-
-	return POWER_SUPPLY_STATUS_NOT_CHARGING;
-}
-
-static void ug3105_work(struct work_struct *work)
-{
-	struct ug3105_chip *chip = container_of(work, struct ug3105_chip,
-						work.work);
-	int i, val, curr_diff, volt_diff, res, win_size;
-	bool prev_supplied = chip->supplied;
-	int prev_status = chip->status;
-	int prev_volt = chip->volt;
-	int prev_curr = chip->curr;
-	struct power_supply *psy;
-
-	mutex_lock(&chip->lock);
-
-	psy = chip->psy;
-	if (!psy)
-		goto out;
-
-	val = ug3105_read_word(chip->client, UG3105_REG_BAT_VOLT);
-	if (val < 0)
-		goto out;
-	chip->volt = val * chip->uv_per_unit;
-
-	val = ug3105_read_word(chip->client, UG3105_REG_BAT_CURR);
-	if (val < 0)
-		goto out;
-	chip->curr = (s16)val * chip->ua_per_unit;
-
-	chip->ocv[chip->ocv_avg_index] =
-		chip->volt - chip->curr * chip->intern_res_avg / 1000;
-	chip->ocv_avg_index = (chip->ocv_avg_index + 1) % UG3105_MOV_AVG_WINDOW;
-	chip->poll_count++;
-
-	/*
-	 * See possible improvements comment above.
-	 *
-	 * Read + reset coulomb counter every 10 polls (every 300 seconds)
-	 * if ((chip->poll_count % 10) == 0) {
-	 *	val = ug3105_read_word(chip->client, UG3105_REG_COULOMB_CNT);
-	 *	if (val < 0)
-	 *		goto out;
-	 *
-	 *	i2c_smbus_write_byte_data(chip->client, UG3105_REG_CTRL1,
-	 *				  UG3105_CTRL1_RESET_COULOMB_CNT);
-	 *
-	 *	chip->total_coulomb_count += (s16)val;
-	 *	dev_dbg(&chip->client->dev, "coulomb count %d total %d\n",
-	 *		(s16)val, chip->total_coulomb_count);
-	 * }
-	 */
-
-	chip->ocv_avg = 0;
-	win_size = min(chip->poll_count, UG3105_MOV_AVG_WINDOW);
-	for (i = 0; i < win_size; i++)
-		chip->ocv_avg += chip->ocv[i];
-	chip->ocv_avg /= win_size;
-
-	chip->supplied = power_supply_am_i_supplied(psy);
-	chip->status = ug3105_get_status(chip);
-	if (chip->status == POWER_SUPPLY_STATUS_FULL)
-		chip->capacity = 100;
-	else
-		chip->capacity = power_supply_batinfo_ocv2cap(chip->psy->battery_info,
-							      chip->ocv_avg,
-							      AMBIENT_TEMP_CELCIUS);
-
-	/*
-	 * Skip internal resistance calc on charger [un]plug and
-	 * when the battery is almost empty (voltage low).
-	 */
-	if (chip->supplied != prev_supplied ||
-	    chip->volt < UG3105_LOW_BAT_UV ||
-	    chip->poll_count < 2)
-		goto out;
-
-	/*
-	 * Assuming that the OCV voltage does not change significantly
-	 * between 2 polls, then we can calculate the internal resistance
-	 * on a significant current change by attributing all voltage
-	 * change between the 2 readings to the internal resistance.
-	 */
-	curr_diff = abs(chip->curr - prev_curr);
-	if (curr_diff < UG3105_CURR_HYST_UA)
-		goto out;
-
-	volt_diff = abs(chip->volt - prev_volt);
-	res = volt_diff * 1000 / curr_diff;
-
-	if ((res < (chip->intern_res_avg * 2 / 3)) ||
-	    (res > (chip->intern_res_avg * 4 / 3))) {
-		dev_dbg(&chip->client->dev, "Ignoring outlier internal resistance %d mOhm\n", res);
-		goto out;
-	}
-
-	dev_dbg(&chip->client->dev, "Internal resistance %d mOhm\n", res);
-
-	chip->intern_res[chip->intern_res_avg_index] = res;
-	chip->intern_res_avg_index = (chip->intern_res_avg_index + 1) % UG3105_MOV_AVG_WINDOW;
-	chip->intern_res_poll_count++;
-
-	chip->intern_res_avg = 0;
-	win_size = min(chip->intern_res_poll_count, UG3105_MOV_AVG_WINDOW);
-	for (i = 0; i < win_size; i++)
-		chip->intern_res_avg += chip->intern_res[i];
-	chip->intern_res_avg /= win_size;
-
-out:
-	mutex_unlock(&chip->lock);
-
-	queue_delayed_work(system_wq, &chip->work,
-			   (chip->poll_count <= UG3105_INIT_POLL_COUNT) ?
-					UG3105_INIT_POLL_TIME : UG3105_POLL_TIME);
-
-	if (chip->status != prev_status && psy)
-		power_supply_changed(psy);
-}
-
-static enum power_supply_property ug3105_battery_props[] = {
-	POWER_SUPPLY_PROP_STATUS,
-	POWER_SUPPLY_PROP_PRESENT,
-	POWER_SUPPLY_PROP_SCOPE,
-	POWER_SUPPLY_PROP_VOLTAGE_NOW,
-	POWER_SUPPLY_PROP_VOLTAGE_OCV,
-	POWER_SUPPLY_PROP_CURRENT_NOW,
-	POWER_SUPPLY_PROP_CAPACITY,
-};
-
-static int ug3105_get_property(struct power_supply *psy,
-			       enum power_supply_property psp,
-			       union power_supply_propval *val)
+static int ug3105_get_voltage_and_current_now(struct power_supply *psy, int *volt, int *curr)
 {
 	struct ug3105_chip *chip = power_supply_get_drvdata(psy);
-	int ret = 0;
+	int ret;
 
-	mutex_lock(&chip->lock);
+	ret = ug3105_read_word(chip->client, UG3105_REG_BAT_VOLT);
+	if (ret < 0)
+		return ret;
 
-	if (!chip->psy) {
-		ret = -EAGAIN;
-		goto out;
-	}
+	*volt = ret * chip->uv_per_unit;
 
-	switch (psp) {
-	case POWER_SUPPLY_PROP_STATUS:
-		val->intval = chip->status;
-		break;
-	case POWER_SUPPLY_PROP_PRESENT:
-		val->intval = 1;
-		break;
-	case POWER_SUPPLY_PROP_SCOPE:
-		val->intval = POWER_SUPPLY_SCOPE_SYSTEM;
-		break;
-	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
-		ret = ug3105_read_word(chip->client, UG3105_REG_BAT_VOLT);
-		if (ret < 0)
-			break;
-		val->intval = ret * chip->uv_per_unit;
-		ret = 0;
-		break;
-	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
-		val->intval = chip->ocv_avg;
-		break;
-	case POWER_SUPPLY_PROP_CURRENT_NOW:
-		ret = ug3105_read_word(chip->client, UG3105_REG_BAT_CURR);
-		if (ret < 0)
-			break;
-		val->intval = (s16)ret * chip->ua_per_unit;
-		ret = 0;
-		break;
-	case POWER_SUPPLY_PROP_CAPACITY:
-		val->intval = chip->capacity;
-		break;
-	default:
-		ret = -EINVAL;
-	}
+	ret = ug3105_read_word(chip->client, UG3105_REG_BAT_CURR);
+	if (ret < 0)
+		return ret;
 
-out:
-	mutex_unlock(&chip->lock);
-	return ret;
-}
-
-static void ug3105_external_power_changed(struct power_supply *psy)
-{
-	struct ug3105_chip *chip = power_supply_get_drvdata(psy);
-
-	dev_dbg(&chip->client->dev, "external power changed\n");
-	mod_delayed_work(system_wq, &chip->work, UG3105_SETTLE_TIME);
+	*curr = (s16)ret * chip->ua_per_unit;
+	return 0;
 }
 
 static const struct power_supply_desc ug3105_psy_desc = {
 	.name		= "ug3105_battery",
 	.type		= POWER_SUPPLY_TYPE_BATTERY,
-	.get_property	= ug3105_get_property,
-	.external_power_changed	= ug3105_external_power_changed,
-	.properties	= ug3105_battery_props,
-	.num_properties	= ARRAY_SIZE(ug3105_battery_props),
+	.get_property	= adc_battery_helper_get_property,
+	.external_power_changed	= adc_battery_helper_external_power_changed,
+	.properties	= adc_battery_helper_properties,
+	.num_properties	= ADC_HELPER_NUM_PROPERTIES,
 };
 
-static void ug3105_init(struct ug3105_chip *chip)
+static void ug3105_start(struct i2c_client *client)
 {
-	chip->poll_count = 0;
-	chip->ocv_avg_index = 0;
-	chip->total_coulomb_count = 0;
-	i2c_smbus_write_byte_data(chip->client, UG3105_REG_MODE,
-				  UG3105_MODE_RUN);
-	i2c_smbus_write_byte_data(chip->client, UG3105_REG_CTRL1,
-				  UG3105_CTRL1_RESET_COULOMB_CNT);
-	queue_delayed_work(system_wq, &chip->work, 0);
-	flush_delayed_work(&chip->work);
+	i2c_smbus_write_byte_data(client, UG3105_REG_MODE, UG3105_MODE_RUN);
+	i2c_smbus_write_byte_data(client, UG3105_REG_CTRL1, UG3105_CTRL1_RESET_COULOMB_CNT);
+}
+
+static void ug3105_stop(struct i2c_client *client)
+{
+	i2c_smbus_write_byte_data(client, UG3105_REG_MODE, UG3105_MODE_STANDBY);
 }
 
 static int ug3105_probe(struct i2c_client *client)
@@ -333,7 +132,6 @@ static int ug3105_probe(struct i2c_client *client)
 	struct power_supply_config psy_cfg = {};
 	struct device *dev = &client->dev;
 	u32 curr_sense_res_uohm = 10000;
-	struct power_supply *psy;
 	struct ug3105_chip *chip;
 	int ret;
 
@@ -342,23 +140,8 @@ static int ug3105_probe(struct i2c_client *client)
 		return -ENOMEM;
 
 	chip->client = client;
-	mutex_init(&chip->lock);
-	ret = devm_delayed_work_autocancel(dev, &chip->work, ug3105_work);
-	if (ret)
-		return ret;
 
-	psy_cfg.drv_data = chip;
-	psy = devm_power_supply_register(dev, &ug3105_psy_desc, &psy_cfg);
-	if (IS_ERR(psy))
-		return PTR_ERR(psy);
-
-	if (!psy->battery_info ||
-	    psy->battery_info->factory_internal_resistance_uohm == -EINVAL ||
-	    psy->battery_info->constant_charge_voltage_max_uv == -EINVAL ||
-	    !psy->battery_info->ocv_table[0]) {
-		dev_err(dev, "error required properties are missing\n");
-		return -ENODEV;
-	}
+	ug3105_start(client);
 
 	device_property_read_u32(dev, "upisemi,rsns-microohm", &curr_sense_res_uohm);
 
@@ -366,35 +149,36 @@ static int ug3105_probe(struct i2c_client *client)
 	 * DAC maximum is 4.5V divided by 65536 steps + an unknown factor of 10
 	 * coming from somewhere for some reason (verified with a volt-meter).
 	 */
-	chip->uv_per_unit = 45000000/65536;
+	chip->uv_per_unit = 45000000 / 65536;
 	/* Datasheet says 8.1 uV per unit for the current ADC */
 	chip->ua_per_unit = 8100000 / curr_sense_res_uohm;
 
-	/* Use provided internal resistance as start point (in milli-ohm) */
-	chip->intern_res_avg = psy->battery_info->factory_internal_resistance_uohm / 1000;
-	/* Also add it to the internal resistance moving average window */
-	chip->intern_res[0] = chip->intern_res_avg;
-	chip->intern_res_avg_index = 1;
-	chip->intern_res_poll_count = 1;
+	psy_cfg.drv_data = chip;
+	chip->psy = devm_power_supply_register(dev, &ug3105_psy_desc, &psy_cfg);
+	if (IS_ERR(chip->psy)) {
+		ret = PTR_ERR(chip->psy);
+		goto stop;
+	}
 
-	mutex_lock(&chip->lock);
-	chip->psy = psy;
-	mutex_unlock(&chip->lock);
-
-	ug3105_init(chip);
+	ret = adc_battery_helper_init(&chip->helper, chip->psy,
+				      ug3105_get_voltage_and_current_now);
+	if (ret)
+		goto stop;
 
 	i2c_set_clientdata(client, chip);
 	return 0;
+
+stop:
+	ug3105_stop(client);
+	return ret;
 }
 
 static int __maybe_unused ug3105_suspend(struct device *dev)
 {
 	struct ug3105_chip *chip = dev_get_drvdata(dev);
 
-	cancel_delayed_work_sync(&chip->work);
-	i2c_smbus_write_byte_data(chip->client, UG3105_REG_MODE,
-				  UG3105_MODE_STANDBY);
-
+	adc_battery_helper_suspend(dev);
+	ug3105_stop(chip->client);
 	return 0;
 }
 
@@ -402,8 +186,8 @@ static int __maybe_unused ug3105_resume(struct device *dev)
 {
 	struct ug3105_chip *chip = dev_get_drvdata(dev);
 
-	ug3105_init(chip);
-
+	ug3105_start(chip->client);
+	adc_battery_helper_resume(dev);
 	return 0;
 }
 
@@ -426,6 +210,6 @@ static struct i2c_driver ug3105_i2c_driver = {
 };
 module_i2c_driver(ug3105_i2c_driver);
 
-MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com");
+MODULE_AUTHOR("Hans de Goede <hansg@kernel.org");
 MODULE_DESCRIPTION("uPI uG3105 battery monitor driver");
 MODULE_LICENSE("GPL");
-- 
2.51.0