extcon: max8997: Use workqueue to check cable state after completing boot of platform

[firefly-linux-kernel-4.4.55.git] / drivers / extcon / extcon-max8997.c

diff --git a/drivers/extcon/extcon-max8997.c b/drivers/extcon/extcon-max8997.c
index 349f65f6a4a451f1b272cb2dce2ae9925159435d..e636d950ad6c15d11d279474d3b55d89b572e257 100644 (file)
--- a/drivers/extcon/extcon-max8997.c
+++ b/drivers/extcon/extcon-max8997.c
@@ -29,6 +29,7 @@
 #include <linux/irqdomain.h>
 
 #define        DEV_NAME                        "max8997-muic"
+#define        DELAY_MS_DEFAULT                20000           /* unit: millisecond */
 
 enum max8997_muic_adc_debounce_time {
        ADC_DEBOUNCE_TIME_0_5MS = 0,    /* 0.5ms */
@@ -128,6 +129,14 @@ struct max8997_muic_info {
        struct max8997_muic_platform_data *muic_pdata;
        enum max8997_muic_charger_type pre_charger_type;
 
+       /*
+        * Use delayed workqueue to detect cable state and then
+        * notify cable state to notifiee/platform through uevent.
+        * After completing the booting of platform, the extcon provider
+        * driver should notify cable state to upper layer.
+        */
+       struct delayed_work wq_detcable;
+
        /*
         * Default usb/uart path whether UART/USB or AUX_UART/AUX_USB
         * h/w path of COMP2/COMN1 on CONTROL1 register.
@@ -629,11 +638,23 @@ static int max8997_muic_detect_dev(struct max8997_muic_info *info)
        return 0;
 }
 
+static void max8997_muic_detect_cable_wq(struct work_struct *work)
+{
+       struct max8997_muic_info *info = container_of(to_delayed_work(work),
+                               struct max8997_muic_info, wq_detcable);
+       int ret;
+
+       ret = max8997_muic_detect_dev(info);
+       if (ret < 0)
+               pr_err("failed to detect cable type\n");
+}
+
 static int max8997_muic_probe(struct platform_device *pdev)
 {
        struct max8997_dev *max8997 = dev_get_drvdata(pdev->dev.parent);
        struct max8997_platform_data *pdata = dev_get_platdata(max8997->dev);
        struct max8997_muic_info *info;
+       int delay_jiffies;
        int ret, i;
 
        info = devm_kzalloc(&pdev->dev, sizeof(struct max8997_muic_info),
@@ -721,17 +742,23 @@ static int max8997_muic_probe(struct platform_device *pdev)
        /* Set ADC debounce time */
        max8997_muic_set_debounce_time(info, ADC_DEBOUNCE_TIME_25MS);
 
-       /* Initial device detection */
-       ret = max8997_muic_detect_dev(info);
-       if (ret < 0) {
-               dev_err(&pdev->dev, "failed to detect cable type\n");
-               goto err_extcon;
-       }
+       /*
+        * Detect accessory after completing the initialization of platform
+        *
+        * - Use delayed workqueue to detect cable state and then
+        * notify cable state to notifiee/platform through uevent.
+        * After completing the booting of platform, the extcon provider
+        * driver should notify cable state to upper layer.
+        */
+       INIT_DELAYED_WORK(&info->wq_detcable, max8997_muic_detect_cable_wq);
+       if (pdata->muic_pdata->detcable_delay_ms)
+               delay_jiffies = msecs_to_jiffies(pdata->muic_pdata->detcable_delay_ms);
+       else
+               delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
+       schedule_delayed_work(&info->wq_detcable, delay_jiffies);
 
-       return ret;
+       return 0;
 
-err_extcon:
-       extcon_dev_unregister(info->edev);
 err_irq:
        while (--i >= 0)
                free_irq(muic_irqs[i].virq, info);