usb: dwc3: msm: add extcon support

Add extcon listeners for EXTCON_USB and EXTCON_USB_HOST cable
types to be notified of VBUS and ID notifications respectively.
Upon notification this will start the controller in either
peripheral or host mode.

This replaces the handling previously done in the power_supply
set_property() callback for PROP_PRESENT and PROP_USB_OTG. The
usb_psy will be removed in its entirety following this patch.

Change-Id: I22405a0a8da21b4c373895500d8dc4c91d97bc51
Signed-off-by: Jack Pham <jackp@codeaurora.org>

Documentation/devicetree/bindings/usb/msm-ssusb.txt

@@ -41,6 +41,12 @@ Optional properties :
 - qcom,disable-dev-mode-pm: If present, it disables PM runtime functionality for device mode.
 - qcom,disable-host-mode-pm: If present, it disables XHCI PM runtime functionality when USB
   host mode is used.
+- extcon: phandles to external connector devices. First phandle should point to
+	  external connector, which provide "USB" cable events, the second
+	  should point to external connector device, which provide "USB-HOST"
+	  cable events. A single phandle may be specified if a single connector
+	  device provides both "USB" and "USB-HOST" events.
+
 Sub nodes:
 - Sub node for "DWC3- USB3 controller".
   This sub node is required property for device node. The properties of this subnode

drivers/usb/dwc3/dwc3-msm.c

@@ -44,6 +44,7 @@
 #include <linux/clk/msm-clk.h>
 #include <linux/msm-bus.h>
 #include <linux/irq.h>
+#include <linux/extcon.h>
 
 #include "power.h"
 #include "core.h"
@@ -198,7 +199,7 @@ struct dwc3_msm {
 	atomic_t                pm_suspended;
 	int			hs_phy_irq;
 	int			ss_phy_irq;
-	struct delayed_work	resume_work;
+	struct work_struct	resume_work;
 	struct work_struct	restart_usb_work;
 	bool			in_restart;
 	struct workqueue_struct *dwc3_wq;
@@ -238,7 +239,12 @@ struct dwc3_msm {
 	unsigned int		irq_to_affin;
 	struct notifier_block	dwc3_cpu_notifier;
 
-	int  pwr_event_irq;
+	struct extcon_dev	*extcon_vbus;
+	struct extcon_dev	*extcon_id;
+	struct notifier_block	vbus_nb;
+	struct notifier_block	id_nb;
+
+	int			pwr_event_irq;
 	atomic_t                in_p3;
 	unsigned int		lpm_to_suspend_delay;
 	bool			init;
@@ -1463,7 +1469,7 @@ static void dwc3_restart_usb_work(struct work_struct *w)
 	chg_type = mdwc->chg_type;
 
 	/* Reset active USB connection */
-	dwc3_resume_work(&mdwc->resume_work.work);
+	dwc3_resume_work(&mdwc->resume_work);
 
 	/* Make sure disconnect is processed before sending connect */
 	while (--timeout && !pm_runtime_suspended(mdwc->dev))
@@ -1481,7 +1487,7 @@ static void dwc3_restart_usb_work(struct work_struct *w)
 	if (mdwc->vbus_active) {
 		mdwc->chg_type = chg_type;
 		mdwc->in_restart = false;
-		dwc3_resume_work(&mdwc->resume_work.work);
+		dwc3_resume_work(&mdwc->resume_work);
 	}
 
 	dwc->err_evt_seen = false;
@@ -1700,8 +1706,7 @@ static void dwc3_msm_notify_event(struct dwc3 *dwc, unsigned event)
 		dev_dbg(mdwc->dev, "DWC3_CONTROLLER_NOTIFY_OTG_EVENT received\n");
 		if (dwc->enable_bus_suspend) {
 			mdwc->suspend = dwc->b_suspend;
-			queue_delayed_work(mdwc->dwc3_wq,
-					&mdwc->resume_work, 0);
+			queue_work(mdwc->dwc3_wq, &mdwc->resume_work);
 		}
 		break;
 	case DWC3_CONTROLLER_SET_CURRENT_DRAW_EVENT:
@@ -2150,8 +2155,7 @@ static void dwc3_ext_event_notify(struct dwc3_msm *mdwc)
 
 static void dwc3_resume_work(struct work_struct *w)
 {
-	struct dwc3_msm *mdwc = container_of(w, struct dwc3_msm,
-							resume_work.work);
+	struct dwc3_msm *mdwc = container_of(w, struct dwc3_msm, resume_work);
 	struct dwc3 *dwc = platform_get_drvdata(mdwc->dwc3);
 
 	dev_dbg(mdwc->dev, "%s: dwc3 resume work\n", __func__);
@@ -2242,7 +2246,7 @@ static irqreturn_t msm_dwc3_pwr_irq_thread(int irq, void *_mdwc)
 	dev_dbg(mdwc->dev, "%s\n", __func__);
 
 	if (atomic_read(&dwc->in_lpm))
-		dwc3_resume_work(&mdwc->resume_work.work);
+		dwc3_resume_work(&mdwc->resume_work);
 	else
 		dwc3_pwr_event_handler(mdwc);
 
@@ -2317,46 +2321,11 @@ static int dwc3_msm_power_set_property_usb(struct power_supply *psy,
 				  const union power_supply_propval *val)
 {
 	struct dwc3_msm *mdwc = power_supply_get_drvdata(psy);
-	struct dwc3 *dwc = platform_get_drvdata(mdwc->dwc3);
 
 	switch (psp) {
 	case POWER_SUPPLY_PROP_USB_OTG:
-		/* Let OTG know about ID detection */
-		mdwc->id_state = val->intval ? DWC3_ID_GROUND : DWC3_ID_FLOAT;
-		dbg_event(0xFF, "id_state", mdwc->id_state);
-		if (dwc->is_drd)
-			queue_delayed_work(mdwc->dwc3_wq,
-					&mdwc->resume_work, 0);
-		break;
-	/* Process PMIC notification in PRESENT prop */
 	case POWER_SUPPLY_PROP_PRESENT:
-		dev_dbg(mdwc->dev, "%s: notify xceiv event with val:%d\n",
-							__func__, val->intval);
-		/*
-		 * Now otg_sm_work() state machine waits for USB cable status.
-		 * Hence here it makes sure that schedule resume work only if
-		 * there is change in USB cable also if there is no USB cable
-		 * notification.
-		 */
-		if (mdwc->otg_state == OTG_STATE_UNDEFINED) {
-			mdwc->vbus_active = val->intval;
-			dwc3_ext_event_notify(mdwc);
-			break;
-		}
-
-		if (mdwc->vbus_active == val->intval)
-			break;
-
-		mdwc->vbus_active = val->intval;
-		if (dwc->is_drd && !mdwc->in_restart) {
-			/*
-			 * Set debouncing delay to 120ms. Otherwise battery
-			 * charging CDP complaince test fails if delay > 120ms.
-			 */
-			dbg_event(0xFF, "Q RW (vbus)", val->intval);
-			queue_delayed_work(mdwc->dwc3_wq,
-					&mdwc->resume_work, 12);
-		}
+		/* no-op; extcon handles VBUS & ID notification */
 		break;
 	case POWER_SUPPLY_PROP_ONLINE:
 		mdwc->online = val->intval;
@@ -2554,6 +2523,97 @@ static int dwc3_msm_get_clk_gdsc(struct dwc3_msm *mdwc)
 	return 0;
 }
 
+static int dwc3_msm_id_notifier(struct notifier_block *nb,
+	unsigned long event, void *ptr)
+{
+	struct dwc3_msm *mdwc = container_of(nb, struct dwc3_msm, id_nb);
+	enum dwc3_id_state id;
+
+	id = event ? DWC3_ID_GROUND : DWC3_ID_FLOAT;
+
+	dev_dbg(mdwc->dev, "host:%ld (id:%d) event received\n", event, id);
+
+	if (mdwc->id_state != id) {
+		mdwc->id_state = id;
+		dbg_event(0xFF, "id_state", mdwc->id_state);
+		queue_work(mdwc->dwc3_wq, &mdwc->resume_work);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int dwc3_msm_vbus_notifier(struct notifier_block *nb,
+	unsigned long event, void *ptr)
+{
+	struct dwc3_msm *mdwc = container_of(nb, struct dwc3_msm, vbus_nb);
+	struct dwc3 *dwc = platform_get_drvdata(mdwc->dwc3);
+
+	dev_dbg(mdwc->dev, "vbus:%ld event received\n", event);
+
+	if (mdwc->vbus_active == event)
+		return NOTIFY_DONE;
+
+	mdwc->vbus_active = event;
+	if (dwc->is_drd && !mdwc->in_restart) {
+		dbg_event(0xFF, "Q RW (vbus)", mdwc->vbus_active);
+		queue_work(mdwc->dwc3_wq, &mdwc->resume_work);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int dwc3_msm_extcon_register(struct dwc3_msm *mdwc)
+{
+	struct device_node *node = mdwc->dev->of_node;
+	struct extcon_dev *edev;
+	int ret = 0;
+
+	if (!of_property_read_bool(node, "extcon"))
+		return 0;
+
+	edev = extcon_get_edev_by_phandle(mdwc->dev, 0);
+	if (IS_ERR(edev) && PTR_ERR(edev) != -ENODEV)
+		return PTR_ERR(edev);
+
+	if (!IS_ERR(edev)) {
+		mdwc->extcon_vbus = edev;
+		mdwc->vbus_nb.notifier_call = dwc3_msm_vbus_notifier;
+		ret = extcon_register_notifier(edev, EXTCON_USB,
+				&mdwc->vbus_nb);
+		if (ret < 0) {
+			dev_err(mdwc->dev, "failed to register notifier for USB\n");
+			return ret;
+		}
+	}
+
+	/* if a second phandle was provided, use it to get a separate edev */
+	if (of_count_phandle_with_args(node, "extcon", NULL) > 1) {
+		edev = extcon_get_edev_by_phandle(mdwc->dev, 1);
+		if (IS_ERR(edev) && PTR_ERR(edev) != -ENODEV) {
+			ret = PTR_ERR(edev);
+			goto err;
+		}
+	}
+
+	if (!IS_ERR(edev)) {
+		mdwc->extcon_id = edev;
+		mdwc->id_nb.notifier_call = dwc3_msm_id_notifier;
+		ret = extcon_register_notifier(edev, EXTCON_USB_HOST,
+				&mdwc->id_nb);
+		if (ret < 0) {
+			dev_err(mdwc->dev, "failed to register notifier for USB-HOST\n");
+			goto err;
+		}
+	}
+
+	return 0;
+err:
+	if (mdwc->extcon_vbus)
+		extcon_unregister_notifier(mdwc->extcon_vbus, EXTCON_USB,
+				&mdwc->vbus_nb);
+	return ret;
+}
+
 static int dwc3_msm_probe(struct platform_device *pdev)
 {
 	struct device_node *node = pdev->dev.of_node, *dwc3_node;
@@ -2583,7 +2643,7 @@ static int dwc3_msm_probe(struct platform_device *pdev)
 	mdwc->dev = &pdev->dev;
 
 	INIT_LIST_HEAD(&mdwc->req_complete_list);
-	INIT_DELAYED_WORK(&mdwc->resume_work, dwc3_resume_work);
+	INIT_WORK(&mdwc->resume_work, dwc3_resume_work);
 	INIT_WORK(&mdwc->restart_usb_work, dwc3_restart_usb_work);
 	INIT_WORK(&mdwc->bus_vote_w, dwc3_msm_bus_vote_w);
 	init_completion(&mdwc->dwc3_xcvr_vbus_init);
@@ -2791,12 +2851,16 @@ static int dwc3_msm_probe(struct platform_device *pdev)
 
 	dwc3_set_notifier(&dwc3_msm_notify_event);
 
+	ret = dwc3_msm_extcon_register(mdwc);
+	if (ret)
+		goto err;
+
 	/* Assumes dwc3 is the first DT child of dwc3-msm */
 	dwc3_node = of_get_next_available_child(node, NULL);
 	if (!dwc3_node) {
 		dev_err(&pdev->dev, "failed to find dwc3 child\n");
 		ret = -ENODEV;
-		goto err;
+		goto put_extcon;
 	}
 
 	ret = of_platform_populate(node, NULL, NULL, &pdev->dev);
@@ -2804,7 +2868,7 @@ static int dwc3_msm_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev,
 				"failed to add create dwc3 core\n");
 		of_node_put(dwc3_node);
-		goto err;
+		goto put_extcon;
 	}
 
 	mdwc->dwc3 = of_find_device_by_node(dwc3_node);
@@ -2889,6 +2953,14 @@ static int dwc3_msm_probe(struct platform_device *pdev)
 	if (of_property_read_bool(node, "qcom,disable-dev-mode-pm"))
 		pm_runtime_get_noresume(mdwc->dev);
 
+	/* Update initial VBUS/ID state from extcon */
+	if (mdwc->extcon_vbus && extcon_get_cable_state_(mdwc->extcon_vbus,
+							EXTCON_USB))
+		dwc3_msm_vbus_notifier(&mdwc->vbus_nb, true, NULL);
+	if (mdwc->extcon_id && extcon_get_cable_state_(mdwc->extcon_id,
+							EXTCON_USB_HOST))
+		dwc3_msm_id_notifier(&mdwc->id_nb, true, NULL);
+
 	schedule_delayed_work(&mdwc->sm_work, 0);
 
 	if (!dwc->is_drd && host_mode) {
@@ -2903,6 +2975,13 @@ put_dwc3:
 	platform_device_put(mdwc->dwc3);
 	if (mdwc->bus_perf_client)
 		msm_bus_scale_unregister_client(mdwc->bus_perf_client);
+put_extcon:
+	if (mdwc->extcon_vbus)
+		extcon_unregister_notifier(mdwc->extcon_vbus, EXTCON_USB,
+				&mdwc->vbus_nb);
+	if (mdwc->extcon_id)
+		extcon_unregister_notifier(mdwc->extcon_id, EXTCON_USB_HOST,
+				&mdwc->id_nb);
 err:
 	return ret;
 }
@@ -3611,7 +3690,7 @@ static int dwc3_msm_pm_resume(struct device *dev)
 	atomic_set(&mdwc->pm_suspended, 0);
 
 	/* kick in otg state machine */
-	queue_delayed_work(mdwc->dwc3_wq, &mdwc->resume_work, 0);
+	queue_work(mdwc->dwc3_wq, &mdwc->resume_work);
 
 	return 0;
 }