[PATCH v2 3/4] power/supply: Add driver for Pegatron Chagall battery

Svyatoslav Ryhel posted 4 patches 8 months, 1 week ago
There is a newer version of this series
[PATCH v2 3/4] power/supply: Add driver for Pegatron Chagall battery
Posted by Svyatoslav Ryhel 8 months, 1 week ago
The Pegatron Chagall is an Android tablet utilizing a customized Cypress
CG7153AM microcontroller (MCU) as its battery fuel gauge. It supports a
single-cell battery and features a dual-color charging LED.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 drivers/power/supply/Kconfig           |  12 +
 drivers/power/supply/Makefile          |   1 +
 drivers/power/supply/chagall-battery.c | 308 +++++++++++++++++++++++++
 3 files changed, 321 insertions(+)
 create mode 100644 drivers/power/supply/chagall-battery.c

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 9f2eef6787f7..d0fc9db524bd 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -107,6 +107,18 @@ config BATTERY_ACT8945A
 	  Say Y here to enable support for power supply provided by
 	  Active-semi ActivePath ACT8945A charger.
 
+config BATTERY_CHAGALL
+	tristate "Pegatron Chagall battery driver"
+	depends on I2C
+	depends on LEDS_CLASS
+	help
+	  Say Y to include support for Cypress CG7153AM IC based battery
+	  fuel gauge with custom firmware found in Pegatron Chagall based
+	  tablet line.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called chagall-battery.
+
 config BATTERY_CPCAP
 	tristate "Motorola CPCAP PMIC battery driver"
 	depends on MFD_CPCAP && IIO
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 59c4a9f40d28..4ecf48a33fdd 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_CHARGER_ADP5061)	+= adp5061.o
 obj-$(CONFIG_BATTERY_ACT8945A)	+= act8945a_charger.o
 obj-$(CONFIG_BATTERY_AXP20X)	+= axp20x_battery.o
 obj-$(CONFIG_CHARGER_AXP20X)	+= axp20x_ac_power.o
+obj-$(CONFIG_BATTERY_CHAGALL)	+= chagall-battery.o
 obj-$(CONFIG_BATTERY_CPCAP)	+= cpcap-battery.o
 obj-$(CONFIG_BATTERY_CW2015)	+= cw2015_battery.o
 obj-$(CONFIG_BATTERY_DS2760)	+= ds2760_battery.o
diff --git a/drivers/power/supply/chagall-battery.c b/drivers/power/supply/chagall-battery.c
new file mode 100644
index 000000000000..1a278331efe7
--- /dev/null
+++ b/drivers/power/supply/chagall-battery.c
@@ -0,0 +1,308 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/array_size.h>
+#include <linux/delay.h>
+#include <linux/devm-helpers.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/power_supply.h>
+#include <linux/regmap.h>
+
+#define CHAGALL_REG_LED_AMBER				0x60
+#define CHAGALL_REG_LED_WHITE				0x70
+#define CHAGALL_REG_BATTERY_TEMPERATURE			0xa2
+#define CHAGALL_REG_BATTERY_VOLTAGE			0xa4
+#define CHAGALL_REG_BATTERY_CURRENT			0xa6
+#define CHAGALL_REG_BATTERY_CAPACITY			0xa8
+#define CHAGALL_REG_BATTERY_CHARGING_CURRENT		0xaa
+#define CHAGALL_REG_BATTERY_CHARGING_VOLTAGE		0xac
+#define CHAGALL_REG_BATTERY_STATUS			0xae
+#define   BATTERY_DISCHARGING				BIT(6)
+#define   BATTERY_FULL_CHARGED				BIT(5)
+#define   BATTERY_FULL_DISCHARGED			BIT(4)
+#define CHAGALL_REG_BATTERY_REMAIN_CAPACITY		0xb0
+#define CHAGALL_REG_BATTERY_FULL_CAPACITY		0xb2
+#define CHAGALL_REG_MAX_COUNT				0xb4
+
+#define CHAGALL_BATTERY_DATA_REFRESH			5000
+#define TEMP_CELSIUS_OFFSET				2731
+
+static const struct regmap_config chagall_battery_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = CHAGALL_REG_MAX_COUNT,
+	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+struct chagall_battery_data {
+	struct regmap *regmap;
+	struct led_classdev amber_led;
+	struct led_classdev white_led;
+	struct power_supply *battery;
+	struct delayed_work poll_work;
+	u16 last_state;
+};
+
+static void chagall_led_set_brightness_amber(struct led_classdev *led,
+					     enum led_brightness brightness)
+{
+	struct chagall_battery_data *cg =
+		container_of(led, struct chagall_battery_data, amber_led);
+
+	regmap_write(cg->regmap, CHAGALL_REG_LED_AMBER, brightness);
+}
+
+static void chagall_led_set_brightness_white(struct led_classdev *led,
+					     enum led_brightness brightness)
+{
+	struct chagall_battery_data *cg =
+		container_of(led, struct chagall_battery_data, white_led);
+
+	regmap_write(cg->regmap, CHAGALL_REG_LED_WHITE, brightness);
+}
+
+static void chagall_leds_status_update(struct chagall_battery_data *cg, int state)
+{
+	switch (state) {
+	case POWER_SUPPLY_STATUS_FULL:
+		led_set_brightness(&cg->amber_led, LED_OFF);
+		led_set_brightness(&cg->white_led,  LED_ON);
+		break;
+
+	case POWER_SUPPLY_STATUS_CHARGING:
+		led_set_brightness(&cg->white_led, LED_OFF);
+		led_set_brightness(&cg->amber_led,  LED_ON);
+		break;
+
+	default:
+		led_set_brightness(&cg->amber_led, LED_OFF);
+		led_set_brightness(&cg->white_led, LED_OFF);
+		break;
+	}
+}
+
+static const enum power_supply_property chagall_battery_properties[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_VOLTAGE_MAX,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CURRENT_MAX,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+};
+
+static const unsigned int chagall_battery_prop_offs[] = {
+	[POWER_SUPPLY_PROP_TEMP] = CHAGALL_REG_BATTERY_TEMPERATURE,
+	[POWER_SUPPLY_PROP_VOLTAGE_NOW] = CHAGALL_REG_BATTERY_VOLTAGE,
+	[POWER_SUPPLY_PROP_CURRENT_NOW] = CHAGALL_REG_BATTERY_CURRENT,
+	[POWER_SUPPLY_PROP_CAPACITY] = CHAGALL_REG_BATTERY_CAPACITY,
+	[POWER_SUPPLY_PROP_CURRENT_MAX] = CHAGALL_REG_BATTERY_CHARGING_CURRENT,
+	[POWER_SUPPLY_PROP_VOLTAGE_MAX] = CHAGALL_REG_BATTERY_CHARGING_VOLTAGE,
+	[POWER_SUPPLY_PROP_STATUS] = CHAGALL_REG_BATTERY_STATUS,
+	[POWER_SUPPLY_PROP_CHARGE_NOW] = CHAGALL_REG_BATTERY_REMAIN_CAPACITY,
+	[POWER_SUPPLY_PROP_CHARGE_FULL] = CHAGALL_REG_BATTERY_FULL_CAPACITY,
+};
+
+static int chagall_battery_get_value(struct chagall_battery_data *cg,
+				     enum power_supply_property psp, u32 *val)
+{
+	if (psp >= ARRAY_SIZE(chagall_battery_prop_offs))
+		return -EINVAL;
+	if (!chagall_battery_prop_offs[psp])
+		return -EINVAL;
+
+	/* Battery data is stored in 2 consecutive registers with little-endian */
+	return regmap_bulk_read(cg->regmap, chagall_battery_prop_offs[psp], val, 2);
+}
+
+static int chagall_battery_get_property(struct power_supply *psy,
+					enum power_supply_property psp,
+					union power_supply_propval *val)
+{
+	struct chagall_battery_data *cg = power_supply_get_drvdata(psy);
+	int ret;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = 1;
+		break;
+
+	default:
+		ret = chagall_battery_get_value(cg, psp, &val->intval);
+		if (ret)
+			return ret;
+
+		switch (psp) {
+		case POWER_SUPPLY_PROP_TEMP:
+			val->intval -= TEMP_CELSIUS_OFFSET;
+			break;
+
+		case POWER_SUPPLY_PROP_VOLTAGE_MAX:
+		case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		case POWER_SUPPLY_PROP_CURRENT_MAX:
+		case POWER_SUPPLY_PROP_CURRENT_NOW:
+		case POWER_SUPPLY_PROP_CHARGE_FULL:
+		case POWER_SUPPLY_PROP_CHARGE_NOW:
+			val->intval *= 1000;
+			break;
+
+		case POWER_SUPPLY_PROP_STATUS:
+			if (val->intval & BATTERY_FULL_CHARGED)
+				val->intval = POWER_SUPPLY_STATUS_FULL;
+			else if (val->intval & BATTERY_FULL_DISCHARGED)
+				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+			else if (val->intval & BATTERY_DISCHARGING)
+				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+			else
+				val->intval = POWER_SUPPLY_STATUS_CHARGING;
+			break;
+
+		default:
+			break;
+		}
+
+		break;
+	}
+
+	return 0;
+}
+
+static void chagall_battery_poll_work(struct work_struct *work)
+{
+	struct chagall_battery_data *cg =
+		container_of(work, struct chagall_battery_data, poll_work.work);
+	u32 state;
+	int ret;
+
+	ret = chagall_battery_get_value(cg, POWER_SUPPLY_PROP_STATUS, &state);
+	if (ret)
+		return;
+
+	if (state & BATTERY_FULL_CHARGED)
+		state = POWER_SUPPLY_STATUS_FULL;
+	else if (state & BATTERY_DISCHARGING)
+		state = POWER_SUPPLY_STATUS_DISCHARGING;
+	else
+		state = POWER_SUPPLY_STATUS_CHARGING;
+
+	if (cg->last_state != state) {
+		cg->last_state = state;
+		power_supply_changed(cg->battery);
+	}
+
+	chagall_leds_status_update(cg, state);
+
+	/* continuously send uevent notification */
+	schedule_delayed_work(&cg->poll_work,
+			      msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));
+}
+
+static const struct power_supply_desc chagall_battery_desc = {
+	.name = "chagall-battery",
+	.type = POWER_SUPPLY_TYPE_BATTERY,
+	.properties = chagall_battery_properties,
+	.num_properties = ARRAY_SIZE(chagall_battery_properties),
+	.get_property = chagall_battery_get_property,
+	.external_power_changed = power_supply_changed,
+};
+
+static int chagall_battery_probe(struct i2c_client *client)
+{
+	struct chagall_battery_data *cg;
+	struct device *dev = &client->dev;
+	struct power_supply_config cfg = { };
+	int ret;
+
+	cg = devm_kzalloc(dev, sizeof(*cg), GFP_KERNEL);
+	if (!cg)
+		return -ENOMEM;
+
+	cfg.drv_data = cg;
+	cfg.fwnode = dev_fwnode(dev);
+
+	i2c_set_clientdata(client, cg);
+
+	cg->regmap = devm_regmap_init_i2c(client, &chagall_battery_regmap_config);
+	if (IS_ERR(cg->regmap))
+		return dev_err_probe(dev, PTR_ERR(cg->regmap), "cannot allocate regmap\n");
+
+	cg->last_state = POWER_SUPPLY_STATUS_UNKNOWN;
+	cg->battery = devm_power_supply_register(dev, &chagall_battery_desc, &cfg);
+	if (IS_ERR(cg->battery))
+		return dev_err_probe(dev, PTR_ERR(cg->battery), "failed to register power supply\n");
+
+	cg->amber_led.name = "power::amber";
+	cg->amber_led.max_brightness = 1;
+	cg->amber_led.flags = LED_CORE_SUSPENDRESUME;
+	cg->amber_led.brightness_set = chagall_led_set_brightness_amber;
+
+	ret = devm_led_classdev_register(dev, &cg->amber_led);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to register amber LED\n");
+
+	cg->white_led.name = "power::white";
+	cg->white_led.max_brightness = 1;
+	cg->white_led.flags = LED_CORE_SUSPENDRESUME;
+	cg->white_led.brightness_set = chagall_led_set_brightness_white;
+
+	ret = devm_led_classdev_register(dev, &cg->white_led);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to register white LED\n");
+
+	led_set_brightness(&cg->amber_led, LED_OFF);
+	led_set_brightness(&cg->white_led, LED_OFF);
+
+	ret = devm_delayed_work_autocancel(dev, &cg->poll_work, chagall_battery_poll_work);
+	if (ret)
+		return ret;
+
+	schedule_delayed_work(&cg->poll_work, msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));
+	return 0;
+}
+
+static int __maybe_unused chagall_battery_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct chagall_battery_data *cg = i2c_get_clientdata(client);
+
+	cancel_delayed_work_sync(&cg->poll_work);
+	return 0;
+}
+
+static int __maybe_unused chagall_battery_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct chagall_battery_data *cg = i2c_get_clientdata(client);
+
+	schedule_delayed_work(&cg->poll_work, msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(chagall_battery_pm_ops,
+			 chagall_battery_suspend, chagall_battery_resume);
+
+static const struct of_device_id chagall_of_match[] = {
+	{ .compatible = "pegatron,chagall-ec" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, chagall_of_match);
+
+static struct i2c_driver chagall_battery_driver = {
+	.driver = {
+		.name = "chagall-battery",
+		.pm = &chagall_battery_pm_ops,
+		.of_match_table = chagall_of_match,
+	},
+	.probe = chagall_battery_probe,
+};
+module_i2c_driver(chagall_battery_driver);
+
+MODULE_AUTHOR("Svyatoslav Ryhel <clamor95@gmail.com>");
+MODULE_DESCRIPTION("Pegatron Chagall fuel gauge driver");
+MODULE_LICENSE("GPL");
-- 
2.43.0
Re: [PATCH v2 3/4] power/supply: Add driver for Pegatron Chagall battery
Posted by Sebastian Reichel 7 months, 3 weeks ago
Hi,

On Sun, Apr 13, 2025 at 02:10:32PM +0300, Svyatoslav Ryhel wrote:
> The Pegatron Chagall is an Android tablet utilizing a customized Cypress
> CG7153AM microcontroller (MCU) as its battery fuel gauge. It supports a
> single-cell battery and features a dual-color charging LED.
> 
> Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> ---

This looks mostly good to me, but I have some comments.

>  drivers/power/supply/Kconfig           |  12 +
>  drivers/power/supply/Makefile          |   1 +
>  drivers/power/supply/chagall-battery.c | 308 +++++++++++++++++++++++++
>  3 files changed, 321 insertions(+)
>  create mode 100644 drivers/power/supply/chagall-battery.c

[...]

> +static void chagall_leds_status_update(struct chagall_battery_data *cg, int state)
> +{
> +	switch (state) {
> +	case POWER_SUPPLY_STATUS_FULL:
> +		led_set_brightness(&cg->amber_led, LED_OFF);
> +		led_set_brightness(&cg->white_led,  LED_ON);
> +		break;
> +
> +	case POWER_SUPPLY_STATUS_CHARGING:
> +		led_set_brightness(&cg->white_led, LED_OFF);
> +		led_set_brightness(&cg->amber_led,  LED_ON);
> +		break;
> +
> +	default:
> +		led_set_brightness(&cg->amber_led, LED_OFF);
> +		led_set_brightness(&cg->white_led, LED_OFF);
> +		break;
> +	}
> +}

Instead of doing this, you should setup LED triggers when
registering the LEDs. The white LED can use power-supply's full_trig
and the orange LED can use power-supply's charging_trig, which
should have the same effect.

> +static const enum power_supply_property chagall_battery_properties[] = {
> +	POWER_SUPPLY_PROP_STATUS,
> +	POWER_SUPPLY_PROP_PRESENT,
> +	POWER_SUPPLY_PROP_VOLTAGE_NOW,
> +	POWER_SUPPLY_PROP_VOLTAGE_MAX,
> +	POWER_SUPPLY_PROP_CURRENT_NOW,
> +	POWER_SUPPLY_PROP_CURRENT_MAX,
> +	POWER_SUPPLY_PROP_CAPACITY,
> +	POWER_SUPPLY_PROP_TEMP,
> +	POWER_SUPPLY_PROP_CHARGE_FULL,
> +	POWER_SUPPLY_PROP_CHARGE_NOW,
> +};
> +
> +static const unsigned int chagall_battery_prop_offs[] = {
> +	[POWER_SUPPLY_PROP_TEMP] = CHAGALL_REG_BATTERY_TEMPERATURE,
> +	[POWER_SUPPLY_PROP_VOLTAGE_NOW] = CHAGALL_REG_BATTERY_VOLTAGE,
> +	[POWER_SUPPLY_PROP_CURRENT_NOW] = CHAGALL_REG_BATTERY_CURRENT,
> +	[POWER_SUPPLY_PROP_CAPACITY] = CHAGALL_REG_BATTERY_CAPACITY,
> +	[POWER_SUPPLY_PROP_CURRENT_MAX] = CHAGALL_REG_BATTERY_CHARGING_CURRENT,
> +	[POWER_SUPPLY_PROP_VOLTAGE_MAX] = CHAGALL_REG_BATTERY_CHARGING_VOLTAGE,
> +	[POWER_SUPPLY_PROP_STATUS] = CHAGALL_REG_BATTERY_STATUS,
> +	[POWER_SUPPLY_PROP_CHARGE_NOW] = CHAGALL_REG_BATTERY_REMAIN_CAPACITY,
> +	[POWER_SUPPLY_PROP_CHARGE_FULL] = CHAGALL_REG_BATTERY_FULL_CAPACITY,
> +};

Please use the same order for chagall_battery_prop_offs and
chagall_battery_properties. Makes it a lot easier to see
that all options have been covered.

> +static int chagall_battery_get_value(struct chagall_battery_data *cg,
> +				     enum power_supply_property psp, u32 *val)
> +{
> +	if (psp >= ARRAY_SIZE(chagall_battery_prop_offs))
> +		return -EINVAL;
> +	if (!chagall_battery_prop_offs[psp])
> +		return -EINVAL;
> +
> +	/* Battery data is stored in 2 consecutive registers with little-endian */
> +	return regmap_bulk_read(cg->regmap, chagall_battery_prop_offs[psp], val, 2);
> +}
> +
> +static int chagall_battery_get_property(struct power_supply *psy,
> +					enum power_supply_property psp,
> +					union power_supply_propval *val)
> +{
> +	struct chagall_battery_data *cg = power_supply_get_drvdata(psy);
> +	int ret;
> +
> +	switch (psp) {
> +	case POWER_SUPPLY_PROP_PRESENT:
> +		val->intval = 1;
> +		break;
> +
> +	default:
> +		ret = chagall_battery_get_value(cg, psp, &val->intval);
> +		if (ret)
> +			return ret;
> +
> +		switch (psp) {
> +		case POWER_SUPPLY_PROP_TEMP:
> +			val->intval -= TEMP_CELSIUS_OFFSET;
> +			break;
> +
> +		case POWER_SUPPLY_PROP_VOLTAGE_MAX:
> +		case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> +		case POWER_SUPPLY_PROP_CURRENT_MAX:
> +		case POWER_SUPPLY_PROP_CURRENT_NOW:
> +		case POWER_SUPPLY_PROP_CHARGE_FULL:
> +		case POWER_SUPPLY_PROP_CHARGE_NOW:
> +			val->intval *= 1000;
> +			break;
> +
> +		case POWER_SUPPLY_PROP_STATUS:
> +			if (val->intval & BATTERY_FULL_CHARGED)
> +				val->intval = POWER_SUPPLY_STATUS_FULL;
> +			else if (val->intval & BATTERY_FULL_DISCHARGED)
> +				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;

Have you tested this path? POWER_SUPPLY_STATUS_NOT_CHARGING is
intended to be used when the battery is neither charging nor
discharging. Does BATTERY_FULL_DISCHARGED mean, that the battery
is fully depleted and not providing any energy at all? Or is this
some kind of "battery level is criticial, you should attach a
power-supply now or the system will be turn off by itself soon"?

> +			else if (val->intval & BATTERY_DISCHARGING)
> +				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
> +			else
> +				val->intval = POWER_SUPPLY_STATUS_CHARGING;
> +			break;
> +
> +		default:
> +			break;
> +		}
> +
> +		break;
> +	}
> +
> +	return 0;
> +}
> +
> +static void chagall_battery_poll_work(struct work_struct *work)
> +{
> +	struct chagall_battery_data *cg =
> +		container_of(work, struct chagall_battery_data, poll_work.work);
> +	u32 state;
> +	int ret;
> +
> +	ret = chagall_battery_get_value(cg, POWER_SUPPLY_PROP_STATUS, &state);
> +	if (ret)
> +		return;
> +
> +	if (state & BATTERY_FULL_CHARGED)
> +		state = POWER_SUPPLY_STATUS_FULL;
> +	else if (state & BATTERY_DISCHARGING)
> +		state = POWER_SUPPLY_STATUS_DISCHARGING;
> +	else
> +		state = POWER_SUPPLY_STATUS_CHARGING;

This basically duplicates the logic from chagall_battery_get_property(),
so put the translation logic into a helper function and use it in
both places.

Greetings,

-- Sebastian
Re: [PATCH v2 3/4] power/supply: Add driver for Pegatron Chagall battery
Posted by Svyatoslav Ryhel 7 months, 3 weeks ago
вт, 29 квіт. 2025 р. о 02:02 Sebastian Reichel
<sebastian.reichel@collabora.com> пише:
>
> Hi,
>
> On Sun, Apr 13, 2025 at 02:10:32PM +0300, Svyatoslav Ryhel wrote:
> > The Pegatron Chagall is an Android tablet utilizing a customized Cypress
> > CG7153AM microcontroller (MCU) as its battery fuel gauge. It supports a
> > single-cell battery and features a dual-color charging LED.
> >
> > Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> > ---
>
> This looks mostly good to me, but I have some comments.
>
> >  drivers/power/supply/Kconfig           |  12 +
> >  drivers/power/supply/Makefile          |   1 +
> >  drivers/power/supply/chagall-battery.c | 308 +++++++++++++++++++++++++
> >  3 files changed, 321 insertions(+)
> >  create mode 100644 drivers/power/supply/chagall-battery.c
>
> [...]
>
> > +static void chagall_leds_status_update(struct chagall_battery_data *cg, int state)
> > +{
> > +     switch (state) {
> > +     case POWER_SUPPLY_STATUS_FULL:
> > +             led_set_brightness(&cg->amber_led, LED_OFF);
> > +             led_set_brightness(&cg->white_led,  LED_ON);
> > +             break;
> > +
> > +     case POWER_SUPPLY_STATUS_CHARGING:
> > +             led_set_brightness(&cg->white_led, LED_OFF);
> > +             led_set_brightness(&cg->amber_led,  LED_ON);
> > +             break;
> > +
> > +     default:
> > +             led_set_brightness(&cg->amber_led, LED_OFF);
> > +             led_set_brightness(&cg->white_led, LED_OFF);
> > +             break;
> > +     }
> > +}
>
> Instead of doing this, you should setup LED triggers when
> registering the LEDs. The white LED can use power-supply's full_trig
> and the orange LED can use power-supply's charging_trig, which
> should have the same effect.
>
> > +static const enum power_supply_property chagall_battery_properties[] = {
> > +     POWER_SUPPLY_PROP_STATUS,
> > +     POWER_SUPPLY_PROP_PRESENT,
> > +     POWER_SUPPLY_PROP_VOLTAGE_NOW,
> > +     POWER_SUPPLY_PROP_VOLTAGE_MAX,
> > +     POWER_SUPPLY_PROP_CURRENT_NOW,
> > +     POWER_SUPPLY_PROP_CURRENT_MAX,
> > +     POWER_SUPPLY_PROP_CAPACITY,
> > +     POWER_SUPPLY_PROP_TEMP,
> > +     POWER_SUPPLY_PROP_CHARGE_FULL,
> > +     POWER_SUPPLY_PROP_CHARGE_NOW,
> > +};
> > +
> > +static const unsigned int chagall_battery_prop_offs[] = {
> > +     [POWER_SUPPLY_PROP_TEMP] = CHAGALL_REG_BATTERY_TEMPERATURE,
> > +     [POWER_SUPPLY_PROP_VOLTAGE_NOW] = CHAGALL_REG_BATTERY_VOLTAGE,
> > +     [POWER_SUPPLY_PROP_CURRENT_NOW] = CHAGALL_REG_BATTERY_CURRENT,
> > +     [POWER_SUPPLY_PROP_CAPACITY] = CHAGALL_REG_BATTERY_CAPACITY,
> > +     [POWER_SUPPLY_PROP_CURRENT_MAX] = CHAGALL_REG_BATTERY_CHARGING_CURRENT,
> > +     [POWER_SUPPLY_PROP_VOLTAGE_MAX] = CHAGALL_REG_BATTERY_CHARGING_VOLTAGE,
> > +     [POWER_SUPPLY_PROP_STATUS] = CHAGALL_REG_BATTERY_STATUS,
> > +     [POWER_SUPPLY_PROP_CHARGE_NOW] = CHAGALL_REG_BATTERY_REMAIN_CAPACITY,
> > +     [POWER_SUPPLY_PROP_CHARGE_FULL] = CHAGALL_REG_BATTERY_FULL_CAPACITY,
> > +};
>
> Please use the same order for chagall_battery_prop_offs and
> chagall_battery_properties. Makes it a lot easier to see
> that all options have been covered.
>
> > +static int chagall_battery_get_value(struct chagall_battery_data *cg,
> > +                                  enum power_supply_property psp, u32 *val)
> > +{
> > +     if (psp >= ARRAY_SIZE(chagall_battery_prop_offs))
> > +             return -EINVAL;
> > +     if (!chagall_battery_prop_offs[psp])
> > +             return -EINVAL;
> > +
> > +     /* Battery data is stored in 2 consecutive registers with little-endian */
> > +     return regmap_bulk_read(cg->regmap, chagall_battery_prop_offs[psp], val, 2);
> > +}
> > +
> > +static int chagall_battery_get_property(struct power_supply *psy,
> > +                                     enum power_supply_property psp,
> > +                                     union power_supply_propval *val)
> > +{
> > +     struct chagall_battery_data *cg = power_supply_get_drvdata(psy);
> > +     int ret;
> > +
> > +     switch (psp) {
> > +     case POWER_SUPPLY_PROP_PRESENT:
> > +             val->intval = 1;
> > +             break;
> > +
> > +     default:
> > +             ret = chagall_battery_get_value(cg, psp, &val->intval);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             switch (psp) {
> > +             case POWER_SUPPLY_PROP_TEMP:
> > +                     val->intval -= TEMP_CELSIUS_OFFSET;
> > +                     break;
> > +
> > +             case POWER_SUPPLY_PROP_VOLTAGE_MAX:
> > +             case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> > +             case POWER_SUPPLY_PROP_CURRENT_MAX:
> > +             case POWER_SUPPLY_PROP_CURRENT_NOW:
> > +             case POWER_SUPPLY_PROP_CHARGE_FULL:
> > +             case POWER_SUPPLY_PROP_CHARGE_NOW:
> > +                     val->intval *= 1000;
> > +                     break;
> > +
> > +             case POWER_SUPPLY_PROP_STATUS:
> > +                     if (val->intval & BATTERY_FULL_CHARGED)
> > +                             val->intval = POWER_SUPPLY_STATUS_FULL;
> > +                     else if (val->intval & BATTERY_FULL_DISCHARGED)
> > +                             val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
>
> Have you tested this path? POWER_SUPPLY_STATUS_NOT_CHARGING is
> intended to be used when the battery is neither charging nor
> discharging. Does BATTERY_FULL_DISCHARGED mean, that the battery
> is fully depleted and not providing any energy at all? Or is this
> some kind of "battery level is criticial, you should attach a
> power-supply now or the system will be turn off by itself soon"?
>

This one is tricky. I have transferred this logic from downstream
kernel and couldn't trigger BATTERY_FULL_DISCHARGED ever. It might be
a brief state you describe as "battery level is criticial, you should
attach a power-supply now or the system will be turn off by itself
soon" but there is no such entry in POWER_SUPPLY_STATUS enum, so I
assumed that  POWER_SUPPLY_STATUS_NOT_CHARGING co-responds to such
state. If this is not the case I will just remove this entry.

> > +                     else if (val->intval & BATTERY_DISCHARGING)
> > +                             val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
> > +                     else
> > +                             val->intval = POWER_SUPPLY_STATUS_CHARGING;
> > +                     break;
> > +
> > +             default:
> > +                     break;
> > +             }
> > +
> > +             break;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static void chagall_battery_poll_work(struct work_struct *work)
> > +{
> > +     struct chagall_battery_data *cg =
> > +             container_of(work, struct chagall_battery_data, poll_work.work);
> > +     u32 state;
> > +     int ret;
> > +
> > +     ret = chagall_battery_get_value(cg, POWER_SUPPLY_PROP_STATUS, &state);
> > +     if (ret)
> > +             return;
> > +
> > +     if (state & BATTERY_FULL_CHARGED)
> > +             state = POWER_SUPPLY_STATUS_FULL;
> > +     else if (state & BATTERY_DISCHARGING)
> > +             state = POWER_SUPPLY_STATUS_DISCHARGING;
> > +     else
> > +             state = POWER_SUPPLY_STATUS_CHARGING;
>
> This basically duplicates the logic from chagall_battery_get_property(),
> so put the translation logic into a helper function and use it in
> both places.
>
> Greetings,
>
> -- Sebastian
Re: [PATCH v2 3/4] power/supply: Add driver for Pegatron Chagall battery
Posted by ALOK TIWARI 8 months, 1 week ago

subject  -> "power: supply:"

On 13-04-2025 16:40, Svyatoslav Ryhel wrote:
> The Pegatron Chagall is an Android tablet utilizing a customized Cypress
> CG7153AM microcontroller (MCU) as its battery fuel gauge. It supports a
> single-cell battery and features a dual-color charging LED.
> 
> Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> ---
>   drivers/power/supply/Kconfig           |  12 +
>   drivers/power/supply/Makefile          |   1 +
>   drivers/power/supply/chagall-battery.c | 308 +++++++++++++++++++++++++
>   3 files changed, 321 insertions(+)
>   create mode 100644 drivers/power/supply/chagall-battery.c
> 
> diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
> index 9f2eef6787f7..d0fc9db524bd 100644
> --- a/drivers/power/supply/Kconfig
> +++ b/drivers/power/supply/Kconfig
> @@ -107,6 +107,18 @@ config BATTERY_ACT8945A
>   	  Say Y here to enable support for power supply provided by
>   	  Active-semi ActivePath ACT8945A charger.
>   
> +config BATTERY_CHAGALL
> +	tristate "Pegatron Chagall battery driver"
> +	depends on I2C
> +	depends on LEDS_CLASS
> +	help
> +	  Say Y to include support for Cypress CG7153AM IC based battery
> +	  fuel gauge with custom firmware found in Pegatron Chagall based
> +	  tablet line.
> +
> +	  This driver can also be built as a module. If so, the module will be
> +	  called chagall-battery.
> +
>   config BATTERY_CPCAP
>   	tristate "Motorola CPCAP PMIC battery driver"
>   	depends on MFD_CPCAP && IIO
> diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
> index 59c4a9f40d28..4ecf48a33fdd 100644
> --- a/drivers/power/supply/Makefile
> +++ b/drivers/power/supply/Makefile
> @@ -23,6 +23,7 @@ obj-$(CONFIG_CHARGER_ADP5061)	+= adp5061.o
>   obj-$(CONFIG_BATTERY_ACT8945A)	+= act8945a_charger.o
>   obj-$(CONFIG_BATTERY_AXP20X)	+= axp20x_battery.o
>   obj-$(CONFIG_CHARGER_AXP20X)	+= axp20x_ac_power.o
> +obj-$(CONFIG_BATTERY_CHAGALL)	+= chagall-battery.o
>   obj-$(CONFIG_BATTERY_CPCAP)	+= cpcap-battery.o
>   obj-$(CONFIG_BATTERY_CW2015)	+= cw2015_battery.o
>   obj-$(CONFIG_BATTERY_DS2760)	+= ds2760_battery.o
> diff --git a/drivers/power/supply/chagall-battery.c b/drivers/power/supply/chagall-battery.c
> new file mode 100644
> index 000000000000..1a278331efe7
> --- /dev/null
> +++ b/drivers/power/supply/chagall-battery.c
> @@ -0,0 +1,308 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later

Blank line require

> +#include <linux/array_size.h>
> +#include <linux/delay.h>
> +#include <linux/devm-helpers.h>
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/leds.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/power_supply.h>
> +#include <linux/regmap.h>
> +
> +#define CHAGALL_REG_LED_AMBER				0x60
> +#define CHAGALL_REG_LED_WHITE				0x70
> +#define CHAGALL_REG_BATTERY_TEMPERATURE			0xa2
> +#define CHAGALL_REG_BATTERY_VOLTAGE			0xa4
> +#define CHAGALL_REG_BATTERY_CURRENT			0xa6
> +#define CHAGALL_REG_BATTERY_CAPACITY			0xa8
> +#define CHAGALL_REG_BATTERY_CHARGING_CURRENT		0xaa
> +#define CHAGALL_REG_BATTERY_CHARGING_VOLTAGE		0xac
> +#define CHAGALL_REG_BATTERY_STATUS			0xae
> +#define   BATTERY_DISCHARGING				BIT(6)
> +#define   BATTERY_FULL_CHARGED				BIT(5)
> +#define   BATTERY_FULL_DISCHARGED			BIT(4)

' ' after "#define", remove extra ' '

> +#define CHAGALL_REG_BATTERY_REMAIN_CAPACITY		0xb0
> +#define CHAGALL_REG_BATTERY_FULL_CAPACITY		0xb2
> +#define CHAGALL_REG_MAX_COUNT				0xb4
> +
> +#define CHAGALL_BATTERY_DATA_REFRESH			5000
> +#define TEMP_CELSIUS_OFFSET				2731
> +
> +static const struct regmap_config chagall_battery_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = CHAGALL_REG_MAX_COUNT,
> +	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
> +	.val_format_endian = REGMAP_ENDIAN_LITTLE,
> +};
> +
> +struct chagall_battery_data {
> +	struct regmap *regmap;
> +	struct led_classdev amber_led;
> +	struct led_classdev white_led;
> +	struct power_supply *battery;
> +	struct delayed_work poll_work;
> +	u16 last_state;
> +};
> +
> +static void chagall_led_set_brightness_amber(struct led_classdev *led,
> +					     enum led_brightness brightness)
> +{
> +	struct chagall_battery_data *cg =
> +		container_of(led, struct chagall_battery_data, amber_led);
> +
> +	regmap_write(cg->regmap, CHAGALL_REG_LED_AMBER, brightness);
> +}
> +
> +static void chagall_led_set_brightness_white(struct led_classdev *led,
> +					     enum led_brightness brightness)
> +{
> +	struct chagall_battery_data *cg =
> +		container_of(led, struct chagall_battery_data, white_led);
> +
> +	regmap_write(cg->regmap, CHAGALL_REG_LED_WHITE, brightness);
> +}
> +
> +static void chagall_leds_status_update(struct chagall_battery_data *cg, int state)
> +{
> +	switch (state) {
> +	case POWER_SUPPLY_STATUS_FULL:
> +		led_set_brightness(&cg->amber_led, LED_OFF);
> +		led_set_brightness(&cg->white_led,  LED_ON);
> +		break;
> +

no Blank line.

> +	case POWER_SUPPLY_STATUS_CHARGING:
> +		led_set_brightness(&cg->white_led, LED_OFF);
> +		led_set_brightness(&cg->amber_led,  LED_ON);
> +		break;
> +

no Blank line.

> +	default:
> +		led_set_brightness(&cg->amber_led, LED_OFF);
> +		led_set_brightness(&cg->white_led, LED_OFF);
> +		break;
> +	}
> +}
> +
> +static const enum power_supply_property chagall_battery_properties[] = {
> +	POWER_SUPPLY_PROP_STATUS,
> +	POWER_SUPPLY_PROP_PRESENT,
> +	POWER_SUPPLY_PROP_VOLTAGE_NOW,
> +	POWER_SUPPLY_PROP_VOLTAGE_MAX,
> +	POWER_SUPPLY_PROP_CURRENT_NOW,
> +	POWER_SUPPLY_PROP_CURRENT_MAX,
> +	POWER_SUPPLY_PROP_CAPACITY,
> +	POWER_SUPPLY_PROP_TEMP,
> +	POWER_SUPPLY_PROP_CHARGE_FULL,
> +	POWER_SUPPLY_PROP_CHARGE_NOW,
> +};
> +
> +static const unsigned int chagall_battery_prop_offs[] = {
> +	[POWER_SUPPLY_PROP_TEMP] = CHAGALL_REG_BATTERY_TEMPERATURE,
> +	[POWER_SUPPLY_PROP_VOLTAGE_NOW] = CHAGALL_REG_BATTERY_VOLTAGE,
> +	[POWER_SUPPLY_PROP_CURRENT_NOW] = CHAGALL_REG_BATTERY_CURRENT,
> +	[POWER_SUPPLY_PROP_CAPACITY] = CHAGALL_REG_BATTERY_CAPACITY,
> +	[POWER_SUPPLY_PROP_CURRENT_MAX] = CHAGALL_REG_BATTERY_CHARGING_CURRENT,
> +	[POWER_SUPPLY_PROP_VOLTAGE_MAX] = CHAGALL_REG_BATTERY_CHARGING_VOLTAGE,
> +	[POWER_SUPPLY_PROP_STATUS] = CHAGALL_REG_BATTERY_STATUS,
> +	[POWER_SUPPLY_PROP_CHARGE_NOW] = CHAGALL_REG_BATTERY_REMAIN_CAPACITY,
> +	[POWER_SUPPLY_PROP_CHARGE_FULL] = CHAGALL_REG_BATTERY_FULL_CAPACITY,
> +};
> +
> +static int chagall_battery_get_value(struct chagall_battery_data *cg,
> +				     enum power_supply_property psp, u32 *val)
> +{
> +	if (psp >= ARRAY_SIZE(chagall_battery_prop_offs))
> +		return -EINVAL;
> +	if (!chagall_battery_prop_offs[psp])
> +		return -EINVAL;
> +
> +	/* Battery data is stored in 2 consecutive registers with little-endian */
> +	return regmap_bulk_read(cg->regmap, chagall_battery_prop_offs[psp], val, 2);
> +}
> +
> +static int chagall_battery_get_property(struct power_supply *psy,
> +					enum power_supply_property psp,
> +					union power_supply_propval *val)
> +{
> +	struct chagall_battery_data *cg = power_supply_get_drvdata(psy);
> +	int ret;
> +
> +	switch (psp) {
> +	case POWER_SUPPLY_PROP_PRESENT:
> +		val->intval = 1;
> +		break;
> +
> +	default:
> +		ret = chagall_battery_get_value(cg, psp, &val->intval);
> +		if (ret)
> +			return ret;
> +
> +		switch (psp) {
> +		case POWER_SUPPLY_PROP_TEMP:
> +			val->intval -= TEMP_CELSIUS_OFFSET;
> +			break;
> +
> +		case POWER_SUPPLY_PROP_VOLTAGE_MAX:
> +		case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> +		case POWER_SUPPLY_PROP_CURRENT_MAX:
> +		case POWER_SUPPLY_PROP_CURRENT_NOW:
> +		case POWER_SUPPLY_PROP_CHARGE_FULL:
> +		case POWER_SUPPLY_PROP_CHARGE_NOW:
> +			val->intval *= 1000;
> +			break;
> +
> +		case POWER_SUPPLY_PROP_STATUS:
> +			if (val->intval & BATTERY_FULL_CHARGED)
> +				val->intval = POWER_SUPPLY_STATUS_FULL;
> +			else if (val->intval & BATTERY_FULL_DISCHARGED)
> +				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +			else if (val->intval & BATTERY_DISCHARGING)
> +				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
> +			else
> +				val->intval = POWER_SUPPLY_STATUS_CHARGING;
> +			break;
> +

no blank line is required between a case label.

> +		default:
> +			break;
> +		}
> +
> +		break;
> +	}
> +
> +	return 0;
> +}
> +
> +static void chagall_battery_poll_work(struct work_struct *work)
> +{
> +	struct chagall_battery_data *cg =
> +		container_of(work, struct chagall_battery_data, poll_work.work);
> +	u32 state;
> +	int ret;
> +
> +	ret = chagall_battery_get_value(cg, POWER_SUPPLY_PROP_STATUS, &state);
> +	if (ret)
> +		return;
> +
> +	if (state & BATTERY_FULL_CHARGED)
> +		state = POWER_SUPPLY_STATUS_FULL;
> +	else if (state & BATTERY_DISCHARGING)
> +		state = POWER_SUPPLY_STATUS_DISCHARGING;
> +	else
> +		state = POWER_SUPPLY_STATUS_CHARGING;
> +
> +	if (cg->last_state != state) {
> +		cg->last_state = state;
> +		power_supply_changed(cg->battery);
> +	}
> +
> +	chagall_leds_status_update(cg, state);
> +
> +	/* continuously send uevent notification */
> +	schedule_delayed_work(&cg->poll_work,
> +			      msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));
> +}
> +
> +static const struct power_supply_desc chagall_battery_desc = {
> +	.name = "chagall-battery",
> +	.type = POWER_SUPPLY_TYPE_BATTERY,
> +	.properties = chagall_battery_properties,
> +	.num_properties = ARRAY_SIZE(chagall_battery_properties),
> +	.get_property = chagall_battery_get_property,
> +	.external_power_changed = power_supply_changed,
> +};
> +
> +static int chagall_battery_probe(struct i2c_client *client)
> +{
> +	struct chagall_battery_data *cg;
> +	struct device *dev = &client->dev;
> +	struct power_supply_config cfg = { };
> +	int ret;
> +
> +	cg = devm_kzalloc(dev, sizeof(*cg), GFP_KERNEL);
> +	if (!cg)
> +		return -ENOMEM;
> +
> +	cfg.drv_data = cg;
> +	cfg.fwnode = dev_fwnode(dev);
> +
> +	i2c_set_clientdata(client, cg);
> +
> +	cg->regmap = devm_regmap_init_i2c(client, &chagall_battery_regmap_config);
> +	if (IS_ERR(cg->regmap))
> +		return dev_err_probe(dev, PTR_ERR(cg->regmap), "cannot allocate regmap\n");
> +
> +	cg->last_state = POWER_SUPPLY_STATUS_UNKNOWN;
> +	cg->battery = devm_power_supply_register(dev, &chagall_battery_desc, &cfg);
> +	if (IS_ERR(cg->battery))
> +		return dev_err_probe(dev, PTR_ERR(cg->battery), "failed to register power supply\n");
> +
> +	cg->amber_led.name = "power::amber";
> +	cg->amber_led.max_brightness = 1;
> +	cg->amber_led.flags = LED_CORE_SUSPENDRESUME;
> +	cg->amber_led.brightness_set = chagall_led_set_brightness_amber;
> +
> +	ret = devm_led_classdev_register(dev, &cg->amber_led);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to register amber LED\n");
> +
> +	cg->white_led.name = "power::white";
> +	cg->white_led.max_brightness = 1;
> +	cg->white_led.flags = LED_CORE_SUSPENDRESUME;
> +	cg->white_led.brightness_set = chagall_led_set_brightness_white;
> +
> +	ret = devm_led_classdev_register(dev, &cg->white_led);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to register white LED\n");
> +
> +	led_set_brightness(&cg->amber_led, LED_OFF);
> +	led_set_brightness(&cg->white_led, LED_OFF);
> +
> +	ret = devm_delayed_work_autocancel(dev, &cg->poll_work, chagall_battery_poll_work);
> +	if (ret)
> +		return ret;
> +
> +	schedule_delayed_work(&cg->poll_work, msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));

a '\n' before return is customary

> +	return 0;
> +}
> +
> +static int __maybe_unused chagall_battery_suspend(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct chagall_battery_data *cg = i2c_get_clientdata(client);
> +
> +	cancel_delayed_work_sync(&cg->poll_work);

a '\n' before return

> +	return 0;
> +}
> +
> +static int __maybe_unused chagall_battery_resume(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct chagall_battery_data *cg = i2c_get_clientdata(client);
> +
> +	schedule_delayed_work(&cg->poll_work, msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));

a '\n' before return is customary

> +	return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(chagall_battery_pm_ops,
> +			 chagall_battery_suspend, chagall_battery_resume);
> +
> +static const struct of_device_id chagall_of_match[] = {
> +	{ .compatible = "pegatron,chagall-ec" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, chagall_of_match);
> +
> +static struct i2c_driver chagall_battery_driver = {
> +	.driver = {
> +		.name = "chagall-battery",
> +		.pm = &chagall_battery_pm_ops,
> +		.of_match_table = chagall_of_match,
> +	},
> +	.probe = chagall_battery_probe,
> +};
> +module_i2c_driver(chagall_battery_driver);
> +
> +MODULE_AUTHOR("Svyatoslav Ryhel <clamor95@gmail.com>");
> +MODULE_DESCRIPTION("Pegatron Chagall fuel gauge driver");
> +MODULE_LICENSE("GPL");



Thanks,
Alok
Re: [PATCH v2 3/4] power/supply: Add driver for Pegatron Chagall battery
Posted by Svyatoslav Ryhel 8 months, 1 week ago
нд, 13 квіт. 2025 р. о 18:16 ALOK TIWARI <alok.a.tiwari@oracle.com> пише:
>
>
>
> subject  -> "power: supply:"
>
> On 13-04-2025 16:40, Svyatoslav Ryhel wrote:
> > The Pegatron Chagall is an Android tablet utilizing a customized Cypress
> > CG7153AM microcontroller (MCU) as its battery fuel gauge. It supports a
> > single-cell battery and features a dual-color charging LED.
> >
> > Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> > ---
> >   drivers/power/supply/Kconfig           |  12 +
> >   drivers/power/supply/Makefile          |   1 +
> >   drivers/power/supply/chagall-battery.c | 308 +++++++++++++++++++++++++
> >   3 files changed, 321 insertions(+)
> >   create mode 100644 drivers/power/supply/chagall-battery.c
> >
> > diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
> > index 9f2eef6787f7..d0fc9db524bd 100644
> > --- a/drivers/power/supply/Kconfig
> > +++ b/drivers/power/supply/Kconfig
> > @@ -107,6 +107,18 @@ config BATTERY_ACT8945A
> >         Say Y here to enable support for power supply provided by
> >         Active-semi ActivePath ACT8945A charger.
> >
> > +config BATTERY_CHAGALL
> > +     tristate "Pegatron Chagall battery driver"
> > +     depends on I2C
> > +     depends on LEDS_CLASS
> > +     help
> > +       Say Y to include support for Cypress CG7153AM IC based battery
> > +       fuel gauge with custom firmware found in Pegatron Chagall based
> > +       tablet line.
> > +
> > +       This driver can also be built as a module. If so, the module will be
> > +       called chagall-battery.
> > +
> >   config BATTERY_CPCAP
> >       tristate "Motorola CPCAP PMIC battery driver"
> >       depends on MFD_CPCAP && IIO
> > diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
> > index 59c4a9f40d28..4ecf48a33fdd 100644
> > --- a/drivers/power/supply/Makefile
> > +++ b/drivers/power/supply/Makefile
> > @@ -23,6 +23,7 @@ obj-$(CONFIG_CHARGER_ADP5061)       += adp5061.o
> >   obj-$(CONFIG_BATTERY_ACT8945A)      += act8945a_charger.o
> >   obj-$(CONFIG_BATTERY_AXP20X)        += axp20x_battery.o
> >   obj-$(CONFIG_CHARGER_AXP20X)        += axp20x_ac_power.o
> > +obj-$(CONFIG_BATTERY_CHAGALL)        += chagall-battery.o
> >   obj-$(CONFIG_BATTERY_CPCAP) += cpcap-battery.o
> >   obj-$(CONFIG_BATTERY_CW2015)        += cw2015_battery.o
> >   obj-$(CONFIG_BATTERY_DS2760)        += ds2760_battery.o
> > diff --git a/drivers/power/supply/chagall-battery.c b/drivers/power/supply/chagall-battery.c
> > new file mode 100644
> > index 000000000000..1a278331efe7
> > --- /dev/null
> > +++ b/drivers/power/supply/chagall-battery.c
> > @@ -0,0 +1,308 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
>
> Blank line require
>
> > +#include <linux/array_size.h>
> > +#include <linux/delay.h>
> > +#include <linux/devm-helpers.h>
> > +#include <linux/err.h>
> > +#include <linux/i2c.h>
> > +#include <linux/leds.h>
> > +#include <linux/mod_devicetable.h>
> > +#include <linux/module.h>
> > +#include <linux/power_supply.h>
> > +#include <linux/regmap.h>
> > +
> > +#define CHAGALL_REG_LED_AMBER                                0x60
> > +#define CHAGALL_REG_LED_WHITE                                0x70
> > +#define CHAGALL_REG_BATTERY_TEMPERATURE                      0xa2
> > +#define CHAGALL_REG_BATTERY_VOLTAGE                  0xa4
> > +#define CHAGALL_REG_BATTERY_CURRENT                  0xa6
> > +#define CHAGALL_REG_BATTERY_CAPACITY                 0xa8
> > +#define CHAGALL_REG_BATTERY_CHARGING_CURRENT         0xaa
> > +#define CHAGALL_REG_BATTERY_CHARGING_VOLTAGE         0xac
> > +#define CHAGALL_REG_BATTERY_STATUS                   0xae
> > +#define   BATTERY_DISCHARGING                                BIT(6)
> > +#define   BATTERY_FULL_CHARGED                               BIT(5)
> > +#define   BATTERY_FULL_DISCHARGED                    BIT(4)
>
> ' ' after "#define", remove extra ' '
>
> > +#define CHAGALL_REG_BATTERY_REMAIN_CAPACITY          0xb0
> > +#define CHAGALL_REG_BATTERY_FULL_CAPACITY            0xb2
> > +#define CHAGALL_REG_MAX_COUNT                                0xb4
> > +
> > +#define CHAGALL_BATTERY_DATA_REFRESH                 5000
> > +#define TEMP_CELSIUS_OFFSET                          2731
> > +
> > +static const struct regmap_config chagall_battery_regmap_config = {
> > +     .reg_bits = 8,
> > +     .val_bits = 8,
> > +     .max_register = CHAGALL_REG_MAX_COUNT,
> > +     .reg_format_endian = REGMAP_ENDIAN_LITTLE,
> > +     .val_format_endian = REGMAP_ENDIAN_LITTLE,
> > +};
> > +
> > +struct chagall_battery_data {
> > +     struct regmap *regmap;
> > +     struct led_classdev amber_led;
> > +     struct led_classdev white_led;
> > +     struct power_supply *battery;
> > +     struct delayed_work poll_work;
> > +     u16 last_state;
> > +};
> > +
> > +static void chagall_led_set_brightness_amber(struct led_classdev *led,
> > +                                          enum led_brightness brightness)
> > +{
> > +     struct chagall_battery_data *cg =
> > +             container_of(led, struct chagall_battery_data, amber_led);
> > +
> > +     regmap_write(cg->regmap, CHAGALL_REG_LED_AMBER, brightness);
> > +}
> > +
> > +static void chagall_led_set_brightness_white(struct led_classdev *led,
> > +                                          enum led_brightness brightness)
> > +{
> > +     struct chagall_battery_data *cg =
> > +             container_of(led, struct chagall_battery_data, white_led);
> > +
> > +     regmap_write(cg->regmap, CHAGALL_REG_LED_WHITE, brightness);
> > +}
> > +
> > +static void chagall_leds_status_update(struct chagall_battery_data *cg, int state)
> > +{
> > +     switch (state) {
> > +     case POWER_SUPPLY_STATUS_FULL:
> > +             led_set_brightness(&cg->amber_led, LED_OFF);
> > +             led_set_brightness(&cg->white_led,  LED_ON);
> > +             break;
> > +
>
> no Blank line.
>
> > +     case POWER_SUPPLY_STATUS_CHARGING:
> > +             led_set_brightness(&cg->white_led, LED_OFF);
> > +             led_set_brightness(&cg->amber_led,  LED_ON);
> > +             break;
> > +
>
> no Blank line.
>
> > +     default:
> > +             led_set_brightness(&cg->amber_led, LED_OFF);
> > +             led_set_brightness(&cg->white_led, LED_OFF);
> > +             break;
> > +     }
> > +}
> > +
> > +static const enum power_supply_property chagall_battery_properties[] = {
> > +     POWER_SUPPLY_PROP_STATUS,
> > +     POWER_SUPPLY_PROP_PRESENT,
> > +     POWER_SUPPLY_PROP_VOLTAGE_NOW,
> > +     POWER_SUPPLY_PROP_VOLTAGE_MAX,
> > +     POWER_SUPPLY_PROP_CURRENT_NOW,
> > +     POWER_SUPPLY_PROP_CURRENT_MAX,
> > +     POWER_SUPPLY_PROP_CAPACITY,
> > +     POWER_SUPPLY_PROP_TEMP,
> > +     POWER_SUPPLY_PROP_CHARGE_FULL,
> > +     POWER_SUPPLY_PROP_CHARGE_NOW,
> > +};
> > +
> > +static const unsigned int chagall_battery_prop_offs[] = {
> > +     [POWER_SUPPLY_PROP_TEMP] = CHAGALL_REG_BATTERY_TEMPERATURE,
> > +     [POWER_SUPPLY_PROP_VOLTAGE_NOW] = CHAGALL_REG_BATTERY_VOLTAGE,
> > +     [POWER_SUPPLY_PROP_CURRENT_NOW] = CHAGALL_REG_BATTERY_CURRENT,
> > +     [POWER_SUPPLY_PROP_CAPACITY] = CHAGALL_REG_BATTERY_CAPACITY,
> > +     [POWER_SUPPLY_PROP_CURRENT_MAX] = CHAGALL_REG_BATTERY_CHARGING_CURRENT,
> > +     [POWER_SUPPLY_PROP_VOLTAGE_MAX] = CHAGALL_REG_BATTERY_CHARGING_VOLTAGE,
> > +     [POWER_SUPPLY_PROP_STATUS] = CHAGALL_REG_BATTERY_STATUS,
> > +     [POWER_SUPPLY_PROP_CHARGE_NOW] = CHAGALL_REG_BATTERY_REMAIN_CAPACITY,
> > +     [POWER_SUPPLY_PROP_CHARGE_FULL] = CHAGALL_REG_BATTERY_FULL_CAPACITY,
> > +};
> > +
> > +static int chagall_battery_get_value(struct chagall_battery_data *cg,
> > +                                  enum power_supply_property psp, u32 *val)
> > +{
> > +     if (psp >= ARRAY_SIZE(chagall_battery_prop_offs))
> > +             return -EINVAL;
> > +     if (!chagall_battery_prop_offs[psp])
> > +             return -EINVAL;
> > +
> > +     /* Battery data is stored in 2 consecutive registers with little-endian */
> > +     return regmap_bulk_read(cg->regmap, chagall_battery_prop_offs[psp], val, 2);
> > +}
> > +
> > +static int chagall_battery_get_property(struct power_supply *psy,
> > +                                     enum power_supply_property psp,
> > +                                     union power_supply_propval *val)
> > +{
> > +     struct chagall_battery_data *cg = power_supply_get_drvdata(psy);
> > +     int ret;
> > +
> > +     switch (psp) {
> > +     case POWER_SUPPLY_PROP_PRESENT:
> > +             val->intval = 1;
> > +             break;
> > +
> > +     default:
> > +             ret = chagall_battery_get_value(cg, psp, &val->intval);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             switch (psp) {
> > +             case POWER_SUPPLY_PROP_TEMP:
> > +                     val->intval -= TEMP_CELSIUS_OFFSET;
> > +                     break;
> > +
> > +             case POWER_SUPPLY_PROP_VOLTAGE_MAX:
> > +             case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> > +             case POWER_SUPPLY_PROP_CURRENT_MAX:
> > +             case POWER_SUPPLY_PROP_CURRENT_NOW:
> > +             case POWER_SUPPLY_PROP_CHARGE_FULL:
> > +             case POWER_SUPPLY_PROP_CHARGE_NOW:
> > +                     val->intval *= 1000;
> > +                     break;
> > +
> > +             case POWER_SUPPLY_PROP_STATUS:
> > +                     if (val->intval & BATTERY_FULL_CHARGED)
> > +                             val->intval = POWER_SUPPLY_STATUS_FULL;
> > +                     else if (val->intval & BATTERY_FULL_DISCHARGED)
> > +                             val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
> > +                     else if (val->intval & BATTERY_DISCHARGING)
> > +                             val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
> > +                     else
> > +                             val->intval = POWER_SUPPLY_STATUS_CHARGING;
> > +                     break;
> > +
>
> no blank line is required between a case label.
>
> > +             default:
> > +                     break;
> > +             }
> > +
> > +             break;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static void chagall_battery_poll_work(struct work_struct *work)
> > +{
> > +     struct chagall_battery_data *cg =
> > +             container_of(work, struct chagall_battery_data, poll_work.work);
> > +     u32 state;
> > +     int ret;
> > +
> > +     ret = chagall_battery_get_value(cg, POWER_SUPPLY_PROP_STATUS, &state);
> > +     if (ret)
> > +             return;
> > +
> > +     if (state & BATTERY_FULL_CHARGED)
> > +             state = POWER_SUPPLY_STATUS_FULL;
> > +     else if (state & BATTERY_DISCHARGING)
> > +             state = POWER_SUPPLY_STATUS_DISCHARGING;
> > +     else
> > +             state = POWER_SUPPLY_STATUS_CHARGING;
> > +
> > +     if (cg->last_state != state) {
> > +             cg->last_state = state;
> > +             power_supply_changed(cg->battery);
> > +     }
> > +
> > +     chagall_leds_status_update(cg, state);
> > +
> > +     /* continuously send uevent notification */
> > +     schedule_delayed_work(&cg->poll_work,
> > +                           msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));
> > +}
> > +
> > +static const struct power_supply_desc chagall_battery_desc = {
> > +     .name = "chagall-battery",
> > +     .type = POWER_SUPPLY_TYPE_BATTERY,
> > +     .properties = chagall_battery_properties,
> > +     .num_properties = ARRAY_SIZE(chagall_battery_properties),
> > +     .get_property = chagall_battery_get_property,
> > +     .external_power_changed = power_supply_changed,
> > +};
> > +
> > +static int chagall_battery_probe(struct i2c_client *client)
> > +{
> > +     struct chagall_battery_data *cg;
> > +     struct device *dev = &client->dev;
> > +     struct power_supply_config cfg = { };
> > +     int ret;
> > +
> > +     cg = devm_kzalloc(dev, sizeof(*cg), GFP_KERNEL);
> > +     if (!cg)
> > +             return -ENOMEM;
> > +
> > +     cfg.drv_data = cg;
> > +     cfg.fwnode = dev_fwnode(dev);
> > +
> > +     i2c_set_clientdata(client, cg);
> > +
> > +     cg->regmap = devm_regmap_init_i2c(client, &chagall_battery_regmap_config);
> > +     if (IS_ERR(cg->regmap))
> > +             return dev_err_probe(dev, PTR_ERR(cg->regmap), "cannot allocate regmap\n");
> > +
> > +     cg->last_state = POWER_SUPPLY_STATUS_UNKNOWN;
> > +     cg->battery = devm_power_supply_register(dev, &chagall_battery_desc, &cfg);
> > +     if (IS_ERR(cg->battery))
> > +             return dev_err_probe(dev, PTR_ERR(cg->battery), "failed to register power supply\n");
> > +
> > +     cg->amber_led.name = "power::amber";
> > +     cg->amber_led.max_brightness = 1;
> > +     cg->amber_led.flags = LED_CORE_SUSPENDRESUME;
> > +     cg->amber_led.brightness_set = chagall_led_set_brightness_amber;
> > +
> > +     ret = devm_led_classdev_register(dev, &cg->amber_led);
> > +     if (ret)
> > +             return dev_err_probe(dev, ret, "failed to register amber LED\n");
> > +
> > +     cg->white_led.name = "power::white";
> > +     cg->white_led.max_brightness = 1;
> > +     cg->white_led.flags = LED_CORE_SUSPENDRESUME;
> > +     cg->white_led.brightness_set = chagall_led_set_brightness_white;
> > +
> > +     ret = devm_led_classdev_register(dev, &cg->white_led);
> > +     if (ret)
> > +             return dev_err_probe(dev, ret, "failed to register white LED\n");
> > +
> > +     led_set_brightness(&cg->amber_led, LED_OFF);
> > +     led_set_brightness(&cg->white_led, LED_OFF);
> > +
> > +     ret = devm_delayed_work_autocancel(dev, &cg->poll_work, chagall_battery_poll_work);
> > +     if (ret)
> > +             return ret;
> > +
> > +     schedule_delayed_work(&cg->poll_work, msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));
>
> a '\n' before return is customary
>
> > +     return 0;
> > +}
> > +
> > +static int __maybe_unused chagall_battery_suspend(struct device *dev)
> > +{
> > +     struct i2c_client *client = to_i2c_client(dev);
> > +     struct chagall_battery_data *cg = i2c_get_clientdata(client);
> > +
> > +     cancel_delayed_work_sync(&cg->poll_work);
>
> a '\n' before return
>
> > +     return 0;
> > +}
> > +
> > +static int __maybe_unused chagall_battery_resume(struct device *dev)
> > +{
> > +     struct i2c_client *client = to_i2c_client(dev);
> > +     struct chagall_battery_data *cg = i2c_get_clientdata(client);
> > +
> > +     schedule_delayed_work(&cg->poll_work, msecs_to_jiffies(CHAGALL_BATTERY_DATA_REFRESH));
>
> a '\n' before return is customary
>
> > +     return 0;
> > +}
> > +
> > +static SIMPLE_DEV_PM_OPS(chagall_battery_pm_ops,
> > +                      chagall_battery_suspend, chagall_battery_resume);
> > +
> > +static const struct of_device_id chagall_of_match[] = {
> > +     { .compatible = "pegatron,chagall-ec" },
> > +     { }
> > +};
> > +MODULE_DEVICE_TABLE(of, chagall_of_match);
> > +
> > +static struct i2c_driver chagall_battery_driver = {
> > +     .driver = {
> > +             .name = "chagall-battery",
> > +             .pm = &chagall_battery_pm_ops,
> > +             .of_match_table = chagall_of_match,
> > +     },
> > +     .probe = chagall_battery_probe,
> > +};
> > +module_i2c_driver(chagall_battery_driver);
> > +
> > +MODULE_AUTHOR("Svyatoslav Ryhel <clamor95@gmail.com>");
> > +MODULE_DESCRIPTION("Pegatron Chagall fuel gauge driver");
> > +MODULE_LICENSE("GPL");
>
>
>
> Thanks,
> Alok

Acknowledged. Thank you.