[RFC 6/6] power: supply: Ettus Research E31x battery driver

From: Virendra Kakade
Date: Mon Feb 11 2019 - 20:03:13 EST

Add support for E31x devices battery which is a sub-device of E31X-PMU.
Enables query of battery properties from device tree.

Signed-off-by: Virendra Kakade <virendra.kakade@xxxxxx>
---
drivers/power/supply/Kconfig | 6 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/e31x-battery.c | 357 ++++++++++++++++++++++++++++
include/linux/mfd/e31x-pmu.h | 15 +-
4 files changed, 377 insertions(+), 2 deletions(-)
create mode 100644 drivers/power/supply/e31x-battery.c

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 3d043b8fd49c..e05e02dffc49 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -666,4 +666,10 @@ config E31X_CHARGER
help
This adds support for the battery charger in Ettus Research E31x PMU.

+config E31X_BATTERY
+ tristate "Ettus Research E31x battery support"
+ depends on MFD_E31X_PMU
+ help
+ This adds support for the battery in Ettus Research E31x PMU.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 6f4f8ca5484e..3850d08db942 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -88,3 +88,4 @@ obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
obj-$(CONFIG_FUEL_GAUGE_SC27XX) += sc27xx_fuel_gauge.o
obj-$(CONFIG_E31X_CHARGER) += e31x-charger.o
+obj-$(CONFIG_E31X_BATTERY) += e31x-battery.o
diff --git a/drivers/power/supply/e31x-battery.c b/drivers/power/supply/e31x-battery.c
new file mode 100644
index 000000000000..d44a639e8bc2
--- /dev/null
+++ b/drivers/power/supply/e31x-battery.c
@@ -0,0 +1,357 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 National Instruments Corp
+ * Author: Virendra Kakade <virendra.kakade@xxxxxx>
+ *
+ * Ettus Research E31x battery driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mutex.h>
+#include <linux/regmap.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/power_supply.h>
+#include <linux/delay.h>
+#include <linux/mfd/e31x-pmu.h>
+
+
+#define E31X_PMU_BATTERY_VOLTAGE_MASK GENMASK(23, 8)
+#define E31X_PMU_BATTERY_VOLTAGE_SHIFT 8
+#define E31X_PMU_BATTERY_TEMP_ALERT_MASK GENMASK(7, 6)
+#define E31X_PMU_BATTERY_TEMP_ALERT_SHIFT 6
+#define E31X_PMU_BATTERY_ONLINE_MASK BIT(5)
+#define E31X_PMU_BATTERY_ONLINE_SHIFT 5
+#define E31X_PMU_BATTERY_HEALTH_MASK GENMASK(4, 2)
+#define E31X_PMU_BATTERY_HEALTH_SHIFT 2
+#define E31X_PMU_BATTERY_STATUS_MASK GENMASK(1, 0)
+#define E31X_PMU_BATTERY_STATUS_SHIFT 0
+
+#define E31X_PMU_GAUGE_TEMP_MASK GENMASK(31, 16)
+#define E31X_PMU_GAUGE_TEMP_SHIFT 16
+#define E31X_PMU_GAUGE_CHARGE_MASK GENMASK(15, 0)
+#define E31X_PMU_GAUGE_CHARGE_SHIFT 0
+
+#define E31X_PMU_GAUGE_VOLTAGE_MASK GENMASK(15, 0)
+#define E31X_PMU_GAUGE_VOLTAGE_SHIFT 0
+
+#define E31X_PMU_GAUGE_CHARGE_LAST_FULL_MASK GENMASK(15, 0)
+#define E31X_PMU_GAUGE_CHARGE_LAST_FULL_SHIFT 0
+
+#define E31X_BATTERY_CHARGE_DESIGN_FULL (3200000)
+#define E31X_PMU_VSENSE (6000)
+
+struct e31x_battery_dev {
+ struct regmap *regmap;
+ struct power_supply *supply;
+};
+
+static int e31x_battery_set_prop(struct power_supply *psy,
+ enum power_supply_property psp,
+ const union power_supply_propval *val)
+{
+ return 0;
+}
+
+static int e31x_battery_get_status(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_CHARGER, &value);
+ if (err)
+ return err;
+
+ value = E31X_PMU_GET_FIELD(CHARGER_ONLINE, value);
+
+ /* if charger is offline, we're discharging, period */
+ if (!value) {
+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+ return 0;
+ }
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_BATTERY, &value);
+ if (err)
+ return err;
+
+ value &= E31X_PMU_BATTERY_STATUS_MASK;
+
+ switch (value) {
+ case 0x0:
+ val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ break;
+ case 0x1:
+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
+ break;
+ case 0x2:
+ val->intval = POWER_SUPPLY_STATUS_FULL;
+ break;
+ case 0x3:
+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+ break;
+ default:
+ return -EIO;
+ };
+
+ return 0;
+}
+
+static int e31x_battery_get_health(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_BATTERY, &value);
+ if (err)
+ return err;
+
+ value = E31X_PMU_GET_FIELD(BATTERY_HEALTH, value);
+
+ switch (value) {
+ case 0x00:
+ val->intval = POWER_SUPPLY_HEALTH_GOOD;
+ break;
+ case 0x01:
+ val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
+ break;
+ case 0x02:
+ val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+ break;
+ case 0x03:
+ val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
+ break;
+ case 0x04:
+ val->intval = POWER_SUPPLY_HEALTH_COLD;
+ break;
+ default:
+ val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
+ break;
+ }
+
+ return 0;
+}
+
+static int e31x_battery_get_online(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_BATTERY, &value);
+ if (err)
+ return err;
+
+ val->intval = !!(value & E31X_PMU_BATTERY_ONLINE_MASK);
+
+ return 0;
+}
+
+static int e31x_battery_get_voltage_now(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_BATTERY, &value);
+
+ if (err)
+ return err;
+
+ value = E31X_PMU_GET_FIELD(BATTERY_VOLTAGE, value);
+
+ val->intval = 10000 * (value * E31X_PMU_VSENSE / GENMASK(15, 0));
+
+ return 0;
+}
+
+#define E31X_PMU_BIN_TO_UAH(x) ((x) * 53)
+#define E31X_PMU_UAH_TO_BIN(x) ((x) / 53)
+
+static int e31x_battery_get_charge_now(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_GAUGE, &value);
+ if (err)
+ return err;
+
+ value = E31X_PMU_GET_FIELD(GAUGE_CHARGE, value);
+ val->intval = E31X_PMU_BIN_TO_UAH(value);
+
+ return 0;
+}
+
+static int e31x_battery_get_temp(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_GAUGE, &value);
+ if (err)
+ return err;
+
+ value = E31X_PMU_GET_FIELD(GAUGE_TEMP, value);
+ val->intval = 10 * (((600 * value) / 0xffff) - 273);
+
+ return 0;
+}
+
+static int e31x_battery_get_charge_full(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_LAST, &value);
+ if (err)
+ return err;
+
+ value = E31X_PMU_GET_FIELD(GAUGE_CHARGE_LAST_FULL, value);
+ val->intval = E31X_PMU_BIN_TO_UAH(value);
+
+ return 0;
+}
+
+static const int e31x_pmu_temp_values[] = {
+ 600, 800, 1000, 1200
+};
+
+static int e31x_battery_get_temp_alert_max(struct e31x_battery_dev *bat,
+ union power_supply_propval *val)
+{
+ u32 value;
+ int err;
+ int i;
+
+ err = regmap_read(bat->regmap, E31X_PMU_REG_BATTERY, &value);
+ if (err)
+ return err;
+
+ value = E31X_PMU_GET_FIELD(BATTERY_TEMP_ALERT, value);
+ for (i = 1; i < ARRAY_SIZE(e31x_pmu_temp_values); i++)
+ if (e31x_pmu_temp_values[i] > value)
+ break;
+
+ val->intval = e31x_pmu_temp_values[i - 1];
+
+ return 0;
+}
+
+static int e31x_battery_get_prop(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct e31x_battery_dev *battery = power_supply_get_drvdata(psy);
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ return e31x_battery_get_status(battery, val);
+ case POWER_SUPPLY_PROP_HEALTH:
+ return e31x_battery_get_health(battery, val);
+ case POWER_SUPPLY_PROP_ONLINE:
+ return e31x_battery_get_online(battery, val);
+ case POWER_SUPPLY_PROP_TECHNOLOGY:
+ val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+ break;
+ case POWER_SUPPLY_PROP_TEMP:
+ return e31x_battery_get_temp(battery, val);
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ return e31x_battery_get_voltage_now(battery, val);
+ case POWER_SUPPLY_PROP_CHARGE_NOW:
+ return e31x_battery_get_charge_now(battery, val);
+ case POWER_SUPPLY_PROP_CHARGE_FULL:
+ return e31x_battery_get_charge_full(battery, val);
+ case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+ val->intval = E31X_BATTERY_CHARGE_DESIGN_FULL;
+ return 0;
+ case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
+ return e31x_battery_get_temp_alert_max(battery, val);
+ default:
+ break;
+ };
+
+ return 0;
+}
+
+static enum power_supply_property e31x_battery_props[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_HEALTH,
+ POWER_SUPPLY_PROP_ONLINE,
+ POWER_SUPPLY_PROP_TECHNOLOGY,
+ POWER_SUPPLY_PROP_TEMP,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_CHARGE_NOW,
+ POWER_SUPPLY_PROP_CHARGE_FULL,
+ POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+ POWER_SUPPLY_PROP_TEMP_ALERT_MAX,
+};
+
+static int e31x_battery_prop_writeable(struct power_supply *psy,
+ enum power_supply_property psp)
+{
+ return psp == POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN ||
+ psp == POWER_SUPPLY_PROP_SCOPE;
+}
+
+static const struct power_supply_desc e31x_battery_desc = {
+ .name = "e31x-battery",
+ .type = POWER_SUPPLY_TYPE_BATTERY,
+ .properties = e31x_battery_props,
+ .num_properties = ARRAY_SIZE(e31x_battery_props),
+ .property_is_writeable = e31x_battery_prop_writeable,
+ .get_property = e31x_battery_get_prop,
+ .set_property = e31x_battery_set_prop,
+};
+
+static const struct of_device_id e31x_battery_id[] = {
+ { .compatible = "ni,e31x-battery" },
+ { },
+};
+
+static int e31x_battery_probe(struct platform_device *pdev)
+{
+ struct power_supply_config psy_cfg = {};
+ struct e31x_battery_dev *battery;
+
+ if (!of_device_is_available(pdev->dev.of_node))
+ return -ENODEV;
+
+ battery = devm_kzalloc(&pdev->dev, sizeof(*battery), GFP_KERNEL);
+ if (!battery)
+ return -ENOMEM;
+
+ battery->regmap = syscon_regmap_lookup_by_phandle(\
+ pdev->dev.parent->of_node, "regmap");
+
+ psy_cfg.of_node = pdev->dev.of_node;
+ psy_cfg.drv_data = battery;
+
+ battery->supply = devm_power_supply_register(&pdev->dev,
+ &e31x_battery_desc,
+ &psy_cfg);
+ if (IS_ERR(battery->supply))
+ return PTR_ERR(battery->supply);
+ return 0;
+}
+
+static struct platform_driver e31x_battery_driver = {
+ .driver = {
+ .name = "e31x-battery",
+ .of_match_table = e31x_battery_id,
+ },
+ .probe = e31x_battery_probe,
+};
+module_platform_driver(e31x_battery_driver);
+
+MODULE_AUTHOR("Virendra Kakade <virendra.kakade@xxxxxx>");
+MODULE_DESCRIPTION("E31x battery driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/e31x-pmu.h b/include/linux/mfd/e31x-pmu.h
index e0649845fe4d..0441f8f896ca 100644
--- a/include/linux/mfd/e31x-pmu.h
+++ b/include/linux/mfd/e31x-pmu.h
@@ -11,13 +11,24 @@

#include <linux/bitops.h>

-#define E31X_PMU_REG_MISC 0x04
-#define E31X_PMU_REG_CHARGER 0x0c
+#define E31X_PMU_REG_MISC 0x04
+#define E31X_PMU_REG_BATTERY 0x08
+#define E31X_PMU_REG_CHARGER 0x0c
+#define E31X_PMU_REG_GAUGE 0x10
+#define E31X_PMU_REG_STATUS 0x14
+#define E31X_PMU_REG_LAST 0x18
+#define E31X_PMU_REG_EEPROM 0x1c

#define E31X_PMU_GET_FIELD(name, reg) \
(((reg) & E31X_PMU_## name ##_MASK) >> \
E31X_PMU_## name ##_SHIFT)

+/* the eeprom register */
+static const u32 E31X_PMU_EEPROM_AUTOBOOT_MASK = BIT(0);
+static const u32 E31X_PMU_EEPROM_AUTOBOOT_SHIFT;
+static const u32 E31X_PMU_EEPROM_DB_POWER_MASK = BIT(1);
+static const u32 E31X_PMU_EEPROM_DB_POWER_SHIFT = 1;
+
#define E31X_PMU_CHARGER_ONLINE_MASK BIT(2)
#define E31X_PMU_CHARGER_ONLINE_SHIFT 2

--
2.17.1