#include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
+#include <linux/extcon.h>
 #include <linux/of_irq.h>
 #include <linux/of_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/power_supply.h>
+#include <linux/workqueue.h>
 #include <linux/gpio.h>
 #include <linux/i2c.h>
 
 #define BQ24190_REG_POC_WDT_RESET_SHIFT                6
 #define BQ24190_REG_POC_CHG_CONFIG_MASK                (BIT(5) | BIT(4))
 #define BQ24190_REG_POC_CHG_CONFIG_SHIFT       4
+#define BQ24190_REG_POC_CHG_CONFIG_CHARGE      1
+#define BQ24190_REG_POC_CHG_CONFIG_OTG         2
 #define BQ24190_REG_POC_SYS_MIN_MASK           (BIT(3) | BIT(2) | BIT(1))
 #define BQ24190_REG_POC_SYS_MIN_SHIFT          1
 #define BQ24190_REG_POC_BOOST_LIM_MASK         BIT(0)
        struct device                   *dev;
        struct power_supply             *charger;
        struct power_supply             *battery;
+       struct extcon_dev               *extcon;
+       struct notifier_block           extcon_nb;
+       struct delayed_work             extcon_work;
        char                            model_name[I2C_NAME_SIZE];
        bool                            initialized;
        bool                            irq_event;
  * number at that index in the array is the real-world value that it
  * represents.
  */
+
+/* REG00[2:0] (IINLIM) in uAh */
+static const int bq24190_iinlim_values[] = {
+       100000, 150000, 500000, 900000, 1200000, 1500000, 2000000, 3000000 };
+
 /* REG02[7:2] (ICHG) in uAh */
 static const int bq24190_ccc_ichg_values[] = {
         512000,  576000,  640000,  704000,  768000,  832000,  896000,  960000,
        return IRQ_HANDLED;
 }
 
+static void bq24190_extcon_work(struct work_struct *work)
+{
+       struct bq24190_dev_info *bdi =
+               container_of(work, struct bq24190_dev_info, extcon_work.work);
+       int ret, iinlim = 0;
+
+       ret = pm_runtime_get_sync(bdi->dev);
+       if (ret < 0) {
+               dev_err(bdi->dev, "Error getting runtime-pm ref: %d\n", ret);
+               return;
+       }
+
+       if (extcon_get_state(bdi->extcon, EXTCON_CHG_USB_SDP) == 1)
+               iinlim = 500000;
+       else if (extcon_get_state(bdi->extcon, EXTCON_CHG_USB_CDP) == 1 ||
+                extcon_get_state(bdi->extcon, EXTCON_CHG_USB_ACA) == 1)
+               iinlim = 1500000;
+       else if (extcon_get_state(bdi->extcon, EXTCON_CHG_USB_DCP) == 1)
+               iinlim = 2000000;
+
+       if (iinlim) {
+               ret = bq24190_set_field_val(bdi, BQ24190_REG_ISC,
+                               BQ24190_REG_ISC_IINLIM_MASK,
+                               BQ24190_REG_ISC_IINLIM_SHIFT,
+                               bq24190_iinlim_values,
+                               ARRAY_SIZE(bq24190_iinlim_values),
+                               iinlim);
+               if (ret)
+                       dev_err(bdi->dev, "Can't set IINLIM: %d\n", ret);
+       }
+
+       /*
+        * If no charger has been detected and host mode is requested, activate
+        * the 5V boost converter, otherwise deactivate it.
+        */
+       if (!iinlim && extcon_get_state(bdi->extcon, EXTCON_USB_HOST) == 1) {
+               ret = bq24190_write_mask(bdi, BQ24190_REG_POC,
+                                        BQ24190_REG_POC_CHG_CONFIG_MASK,
+                                        BQ24190_REG_POC_CHG_CONFIG_SHIFT,
+                                        BQ24190_REG_POC_CHG_CONFIG_OTG);
+       } else {
+               ret = bq24190_write_mask(bdi, BQ24190_REG_POC,
+                                        BQ24190_REG_POC_CHG_CONFIG_MASK,
+                                        BQ24190_REG_POC_CHG_CONFIG_SHIFT,
+                                        BQ24190_REG_POC_CHG_CONFIG_CHARGE);
+       }
+       if (ret)
+               dev_err(bdi->dev, "Can't set CHG_CONFIG: %d\n", ret);
+
+       pm_runtime_mark_last_busy(bdi->dev);
+       pm_runtime_put_autosuspend(bdi->dev);
+}
+
+static int bq24190_extcon_event(struct notifier_block *nb, unsigned long event,
+                               void *param)
+{
+       struct bq24190_dev_info *bdi =
+               container_of(nb, struct bq24190_dev_info, extcon_nb);
+
+       /*
+        * The Power-Good detection may take up to 220ms, sometimes
+        * the external charger detection is quicker, and the bq24190 will
+        * reset to iinlim based on its own charger detection (which is not
+        * hooked up when using external charger detection) resulting in
+        * a too low default 500mA iinlim. Delay applying the extcon value
+        * for 300ms to avoid this.
+        */
+       queue_delayed_work(system_wq, &bdi->extcon_work, msecs_to_jiffies(300));
+
+       return NOTIFY_OK;
+}
+
 static int bq24190_hw_init(struct bq24190_dev_info *bdi)
 {
        u8 v;
        struct device *dev = &client->dev;
        struct power_supply_config charger_cfg = {}, battery_cfg = {};
        struct bq24190_dev_info *bdi;
+       const char *name;
        int ret;
 
        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
                return -EINVAL;
        }
 
+       /*
+        * The extcon-name property is purely an in kernel interface for
+        * x86/ACPI use, DT platforms should get extcon via phandle.
+        */
+       if (device_property_read_string(dev, "extcon-name", &name) == 0) {
+               bdi->extcon = extcon_get_extcon_dev(name);
+               if (!bdi->extcon)
+                       return -EPROBE_DEFER;
+
+               dev_info(bdi->dev, "using extcon device %s\n", name);
+       }
+
        pm_runtime_enable(dev);
        pm_runtime_use_autosuspend(dev);
        pm_runtime_set_autosuspend_delay(dev, 600);
                goto out5;
        }
 
+       if (bdi->extcon) {
+               INIT_DELAYED_WORK(&bdi->extcon_work, bq24190_extcon_work);
+               bdi->extcon_nb.notifier_call = bq24190_extcon_event;
+               ret = devm_extcon_register_notifier(dev, bdi->extcon, -1,
+                                                   &bdi->extcon_nb);
+               if (ret)
+                       goto out5;
+
+               /* Sync initial cable state */
+               queue_delayed_work(system_wq, &bdi->extcon_work, 0);
+       }
+
        enable_irq_wake(client->irq);
 
        pm_runtime_mark_last_busy(dev);