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@xxxxxxxxx>
---
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@xxxxxxxxx>");
+MODULE_DESCRIPTION("Pegatron Chagall fuel gauge driver");
+MODULE_LICENSE("GPL");
--
2.43.0
