usb: phy: msm: Use extcon framework for VBUS and ID detection

On recent Qualcomm platforms VBUS and ID lines are not routed to
USB PHY LINK controller. Use extcon framework to receive connect
and disconnect ID and VBUS notification.

Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

2 files changed, 85 insertions, 0 deletions

diff --git a/drivers/usb/phy/Kconfig b/drivers/usb/phy/Kconfig
index 2175678e674e..811f331892d7 100644
--- a/drivers/usb/phy/Kconfig
+++ b/drivers/usb/phy/Kconfig
@@ -141,6 +141,7 @@ config USB_MSM_OTG
 	tristate "Qualcomm on-chip USB OTG controller support"
 	depends on (USB || USB_GADGET) && (ARCH_QCOM || COMPILE_TEST)
 	depends on RESET_CONTROLLER
+	depends on EXTCON
 	select USB_PHY
 	help
 	  Enable this to support the USB OTG transceiver on Qualcomm chips. It
diff --git a/drivers/usb/phy/phy-msm-usb.c b/drivers/usb/phy/phy-msm-usb.c
index c9156beeadef..ad66c67ce9a5 100644
--- a/drivers/usb/phy/phy-msm-usb.c
+++ b/drivers/usb/phy/phy-msm-usb.c
@@ -1436,9 +1436,42 @@ static const struct of_device_id msm_otg_dt_match[] = {
 };
 MODULE_DEVICE_TABLE(of, msm_otg_dt_match);
 
+static int msm_otg_vbus_notifier(struct notifier_block *nb, unsigned long event,
+				void *ptr)
+{
+	struct msm_usb_cable *vbus = container_of(nb, struct msm_usb_cable, nb);
+	struct msm_otg *motg = container_of(vbus, struct msm_otg, vbus);
+
+	if (event)
+		set_bit(B_SESS_VLD, &motg->inputs);
+	else
+		clear_bit(B_SESS_VLD, &motg->inputs);
+
+	schedule_work(&motg->sm_work);
+
+	return NOTIFY_DONE;
+}
+
+static int msm_otg_id_notifier(struct notifier_block *nb, unsigned long event,
+				void *ptr)
+{
+	struct msm_usb_cable *id = container_of(nb, struct msm_usb_cable, nb);
+	struct msm_otg *motg = container_of(id, struct msm_otg, id);
+
+	if (event)
+		clear_bit(ID, &motg->inputs);
+	else
+		set_bit(ID, &motg->inputs);
+
+	schedule_work(&motg->sm_work);
+
+	return NOTIFY_DONE;
+}
+
 static int msm_otg_read_dt(struct platform_device *pdev, struct msm_otg *motg)
 {
 	struct msm_otg_platform_data *pdata;
+	struct extcon_dev *ext_id, *ext_vbus;
 	const struct of_device_id *id;
 	struct device_node *node = pdev->dev.of_node;
 	struct property *prop;
@@ -1487,6 +1520,52 @@ static int msm_otg_read_dt(struct platform_device *pdev, struct msm_otg *motg)
 		motg->vdd_levels[VDD_LEVEL_MAX] = tmp[VDD_LEVEL_MAX];
 	}
 
+	ext_id = ERR_PTR(-ENODEV);
+	ext_vbus = ERR_PTR(-ENODEV);
+	if (of_property_read_bool(node, "extcon")) {
+
+		/* Each one of them is not mandatory */
+		ext_vbus = extcon_get_edev_by_phandle(&pdev->dev, 0);
+		if (IS_ERR(ext_vbus) && PTR_ERR(ext_vbus) != -ENODEV)
+			return PTR_ERR(ext_vbus);
+
+		ext_id = extcon_get_edev_by_phandle(&pdev->dev, 1);
+		if (IS_ERR(ext_id) && PTR_ERR(ext_id) != -ENODEV)
+			return PTR_ERR(ext_id);
+	}
+
+	if (!IS_ERR(ext_vbus)) {
+		motg->vbus.nb.notifier_call = msm_otg_vbus_notifier;
+		ret = extcon_register_interest(&motg->vbus.conn, ext_vbus->name,
+					       "USB", &motg->vbus.nb);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "register VBUS notifier failed\n");
+			return ret;
+		}
+
+		ret = extcon_get_cable_state(ext_vbus, "USB");
+		if (ret)
+			set_bit(B_SESS_VLD, &motg->inputs);
+		else
+			clear_bit(B_SESS_VLD, &motg->inputs);
+	}
+
+	if (!IS_ERR(ext_id)) {
+		motg->id.nb.notifier_call = msm_otg_id_notifier;
+		ret = extcon_register_interest(&motg->id.conn, ext_id->name,
+					       "USB-HOST", &motg->id.nb);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "register ID notifier failed\n");
+			return ret;
+		}
+
+		ret = extcon_get_cable_state(ext_id, "USB-HOST");
+		if (ret)
+			clear_bit(ID, &motg->inputs);
+		else
+			set_bit(ID, &motg->inputs);
+	}
+
 	prop = of_find_property(node, "qcom,phy-init-sequence", &len);
 	if (!prop || !len)
 		return 0;
@@ -1700,6 +1779,11 @@ static int msm_otg_remove(struct platform_device *pdev)
 	if (phy->otg->host || phy->otg->gadget)
 		return -EBUSY;
 
+	if (motg->id.conn.edev)
+		extcon_unregister_interest(&motg->id.conn);
+	if (motg->vbus.conn.edev)
+		extcon_unregister_interest(&motg->vbus.conn);
+
 	msm_otg_debugfs_cleanup();
 	cancel_delayed_work_sync(&motg->chg_work);
 	cancel_work_sync(&motg->sm_work);