power: supply: act8945a_charger: Add capacity level property

Add the power supply capacity level property, it corresponds to
POWER_SUPPLY_CAPACITY_LEVEL_*.

It also utilizes the precision voltage detector function module
to catch the low battery voltage.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

1 files changed, 78 insertions, 1 deletions

diff --git a/drivers/power/supply/act8945a_charger.c b/drivers/power/supply/act8945a_charger.c
index 48775f8233f3..2f875997d97a 100644
--- a/drivers/power/supply/act8945a_charger.c
+++ b/drivers/power/supply/act8945a_charger.c
@@ -18,6 +18,7 @@
 #include <linux/platform_device.h>
 #include <linux/power_supply.h>
 #include <linux/regmap.h>
+#include <linux/gpio/consumer.h>
 
 static const char *act8945a_charger_model = "ACT8945A";
 static const char *act8945a_charger_manufacturer = "Active-semi";
@@ -83,6 +84,7 @@ struct act8945a_charger {
         struct work_struct work;
 
         bool init_done;
+        struct gpio_desc *lbo_gpio;
 };
 
 static int act8945a_get_charger_state(struct regmap *regmap, int *val)
@@ -208,11 +210,67 @@ static int act8945a_get_battery_health(struct regmap *regmap, int *val)
         return 0;
 }
 
+static int act8945a_get_capacity_level(struct act8945a_charger *charger,
+                                       struct regmap *regmap, int *val)
+{
+        int ret;
+        unsigned int status, state, config;
+        int lbo_level = gpiod_get_value(charger->lbo_gpio);
+
+        ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
+        if (ret < 0)
+                return ret;
+
+        ret = regmap_read(regmap, ACT8945A_APCH_CFG, &config);
+        if (ret < 0)
+                return ret;
+
+        ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
+        if (ret < 0)
+                return ret;
+
+        state &= APCH_STATE_CSTATE;
+        state >>= APCH_STATE_CSTATE_SHIFT;
+
+        switch (state) {
+        case APCH_STATE_CSTATE_PRE:
+                *val = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+                break;
+        case APCH_STATE_CSTATE_FAST:
+                if (lbo_level)
+                        *val = POWER_SUPPLY_CAPACITY_LEVEL_HIGH;
+                else
+                        *val = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+                break;
+        case APCH_STATE_CSTATE_EOC:
+                if (status & APCH_STATUS_CHGDAT)
+                        *val = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+                else
+                        *val = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+                break;
+        case APCH_STATE_CSTATE_DISABLED:
+        default:
+                if (config & APCH_CFG_SUSCHG) {
+                        *val = POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
+                } else {
+                        *val = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+                        if (!(status & APCH_STATUS_INDAT)) {
+                                if (!lbo_level)
+                                        *val = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
+                        }
+                }
+                break;
+        }
+
+        return 0;
+}
+
 static enum power_supply_property act8945a_charger_props[] = {
         POWER_SUPPLY_PROP_STATUS,
         POWER_SUPPLY_PROP_CHARGE_TYPE,
         POWER_SUPPLY_PROP_TECHNOLOGY,
         POWER_SUPPLY_PROP_HEALTH,
+        POWER_SUPPLY_PROP_CAPACITY_LEVEL,
         POWER_SUPPLY_PROP_MODEL_NAME,
         POWER_SUPPLY_PROP_MANUFACTURER
 };
@@ -238,6 +296,10 @@ static int act8945a_charger_get_property(struct power_supply *psy,
         case POWER_SUPPLY_PROP_HEALTH:
                 ret = act8945a_get_battery_health(regmap, &val->intval);
                 break;
+        case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
+                ret = act8945a_get_capacity_level(charger,
+                                                  regmap, &val->intval);
+                break;
         case POWER_SUPPLY_PROP_MODEL_NAME:
                 val->strval = act8945a_charger_model;
                 break;
@@ -335,7 +397,7 @@ static int act8945a_charger_config(struct device *dev,
         u32 pre_time_out;
         u32 input_voltage_threshold;
         int chglev_pin;
-        int ret;
+        int err, ret;
 
         unsigned int tmp;
         unsigned int value = 0;
@@ -354,6 +416,21 @@ static int act8945a_charger_config(struct device *dev,
                 dev_info(dev, "have been suspended\n");
         }
 
+        charger->lbo_gpio = devm_gpiod_get_optional(dev, "active-semi,lbo",
+                                                    GPIOD_IN);
+        if (IS_ERR(charger->lbo_gpio)) {
+                err = PTR_ERR(charger->lbo_gpio);
+                dev_err(dev, "unable to claim gpio \"lbo\": %d\n", err);
+                return err;
+        }
+
+        ret = devm_request_irq(dev, gpiod_to_irq(charger->lbo_gpio),
+                               act8945a_status_changed,
+                               (IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),
+                               "act8945a_lbo_detect", charger);
+        if (ret)
+                dev_info(dev, "failed to request gpio \"lbo\" IRQ\n");
+
         chglev_pin = of_get_named_gpio_flags(np,
                                 "active-semi,chglev-gpios", 0, &flags);