phy-sun4i-usb: Add support for monitoring vbus via a power-supply

[karo-tx-linux.git] / drivers / phy / phy-sun4i-usb.c

diff --git a/drivers/phy/phy-sun4i-usb.c b/drivers/phy/phy-sun4i-usb.c
index 4ba9856ac71a359a658edcece36f96d42c5088ca..5138843ec42d33a3af5d08c655119f3e4adfca65 100644 (file)
--- a/drivers/phy/phy-sun4i-usb.c
+++ b/drivers/phy/phy-sun4i-usb.c
@@ -36,6 +36,7 @@
 #include <linux/phy/phy.h>
 #include <linux/phy/phy-sun4i-usb.h>
 #include <linux/platform_device.h>
+#include <linux/power_supply.h>
 #include <linux/regulator/consumer.h>
 #include <linux/reset.h>
 #include <linux/workqueue.h>
@@ -108,6 +109,9 @@ struct sun4i_usb_phy_data {
        bool phy0_poll;
        struct gpio_desc *id_det_gpio;
        struct gpio_desc *vbus_det_gpio;
+       struct power_supply *vbus_power_supply;
+       struct notifier_block vbus_power_nb;
+       bool vbus_power_nb_registered;
        int id_det_irq;
        int vbus_det_irq;
        int id_det;
@@ -352,6 +356,30 @@ static struct phy_ops sun4i_usb_phy_ops = {
        .owner          = THIS_MODULE,
 };
 
+static int sun4i_usb_phy0_get_vbus_det(struct sun4i_usb_phy_data *data)
+{
+       if (data->vbus_det_gpio)
+               return gpiod_get_value_cansleep(data->vbus_det_gpio);
+
+       if (data->vbus_power_supply) {
+               union power_supply_propval val;
+               int r;
+
+               r = power_supply_get_property(data->vbus_power_supply,
+                                             POWER_SUPPLY_PROP_PRESENT, &val);
+               if (r == 0)
+                       return val.intval;
+       }
+
+       /* Fallback: report vbus as high */
+       return 1;
+}
+
+static bool sun4i_usb_phy0_have_vbus_det(struct sun4i_usb_phy_data *data)
+{
+       return data->vbus_det_gpio || data->vbus_power_supply;
+}
+
 static void sun4i_usb_phy0_id_vbus_det_scan(struct work_struct *work)
 {
        struct sun4i_usb_phy_data *data =
@@ -360,10 +388,7 @@ static void sun4i_usb_phy0_id_vbus_det_scan(struct work_struct *work)
        int id_det, vbus_det, id_notify = 0, vbus_notify = 0;
 
        id_det = gpiod_get_value_cansleep(data->id_det_gpio);
-       if (data->vbus_det_gpio)
-               vbus_det = gpiod_get_value_cansleep(data->vbus_det_gpio);
-       else
-               vbus_det = 1; /* Report vbus as high */
+       vbus_det = sun4i_usb_phy0_get_vbus_det(data);
 
        mutex_lock(&phy0->mutex);
 
@@ -378,7 +403,7 @@ static void sun4i_usb_phy0_id_vbus_det_scan(struct work_struct *work)
                 * without vbus detection report vbus low for long enough for
                 * the musb-ip to end the current device session.
                 */
-               if (!data->vbus_det_gpio && id_det == 0) {
+               if (!sun4i_usb_phy0_have_vbus_det(data) && id_det == 0) {
                        sun4i_usb_phy0_set_vbus_detect(phy0, 0);
                        msleep(200);
                        sun4i_usb_phy0_set_vbus_detect(phy0, 1);
@@ -404,7 +429,7 @@ static void sun4i_usb_phy0_id_vbus_det_scan(struct work_struct *work)
                 * without vbus detection report vbus low for long enough to
                 * the musb-ip to end the current host session.
                 */
-               if (!data->vbus_det_gpio && id_det == 1) {
+               if (!sun4i_usb_phy0_have_vbus_det(data) && id_det == 1) {
                        mutex_lock(&phy0->mutex);
                        sun4i_usb_phy0_set_vbus_detect(phy0, 0);
                        msleep(1000);
@@ -430,6 +455,20 @@ static irqreturn_t sun4i_usb_phy0_id_vbus_det_irq(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
+static int sun4i_usb_phy0_vbus_notify(struct notifier_block *nb,
+                                     unsigned long val, void *v)
+{
+       struct sun4i_usb_phy_data *data =
+               container_of(nb, struct sun4i_usb_phy_data, vbus_power_nb);
+       struct power_supply *psy = v;
+
+       /* Properties on the vbus_power_supply changed, scan vbus_det */
+       if (val == PSY_EVENT_PROP_CHANGED && psy == data->vbus_power_supply)
+               mod_delayed_work(system_wq, &data->detect, DEBOUNCE_TIME);
+
+       return NOTIFY_OK;
+}
+
 static struct phy *sun4i_usb_phy_xlate(struct device *dev,
                                        struct of_phandle_args *args)
 {
@@ -446,6 +485,8 @@ static int sun4i_usb_phy_remove(struct platform_device *pdev)
        struct device *dev = &pdev->dev;
        struct sun4i_usb_phy_data *data = dev_get_drvdata(dev);
 
+       if (data->vbus_power_nb_registered)
+               power_supply_unreg_notifier(&data->vbus_power_nb);
        if (data->id_det_irq >= 0)
                devm_free_irq(dev, data->id_det_irq, data);
        if (data->vbus_det_irq >= 0)
@@ -522,8 +563,18 @@ static int sun4i_usb_phy_probe(struct platform_device *pdev)
                data->vbus_det_gpio = NULL;
        }
 
+       if (of_find_property(np, "usb0_vbus_power-supply", NULL)) {
+               data->vbus_power_supply = devm_power_supply_get_by_phandle(dev,
+                                                    "usb0_vbus_power-supply");
+               if (IS_ERR(data->vbus_power_supply))
+                       return PTR_ERR(data->vbus_power_supply);
+
+               if (!data->vbus_power_supply)
+                       return -EPROBE_DEFER;
+       }
+
        /* vbus_det without id_det makes no sense, and is not supported */
-       if (data->vbus_det_gpio && !data->id_det_gpio) {
+       if (sun4i_usb_phy0_have_vbus_det(data) && !data->id_det_gpio) {
                dev_err(dev, "usb0_id_det missing or invalid\n");
                return -ENODEV;
        }
@@ -620,6 +671,17 @@ static int sun4i_usb_phy_probe(struct platform_device *pdev)
                }
        }
 
+       if (data->vbus_power_supply) {
+               data->vbus_power_nb.notifier_call = sun4i_usb_phy0_vbus_notify;
+               data->vbus_power_nb.priority = 0;
+               ret = power_supply_reg_notifier(&data->vbus_power_nb);
+               if (ret) {
+                       sun4i_usb_phy_remove(pdev); /* Stop detect work */
+                       return ret;
+               }
+               data->vbus_power_nb_registered = true;
+       }
+
        phy_provider = devm_of_phy_provider_register(dev, sun4i_usb_phy_xlate);
        if (IS_ERR(phy_provider)) {
                sun4i_usb_phy_remove(pdev); /* Stop detect work */