1 files changed, 120 insertions, 0 deletions
diff --git a/drivers/usb/chipidea/otg.c b/drivers/usb/chipidea/otg.c
new file mode 100644
index 000000000000..39bd7ec8bf75
--- /dev/null
+++ b/drivers/usb/chipidea/otg.c
@@ -0,0 +1,120 @@
+/*
+ * otg.c - ChipIdea USB IP core OTG driver
+ *
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ * Author: Peter Chen
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This file mainly handles otgsc register, it may include OTG operation
+ * in the future.
+ */
+
+#include <linux/usb/otg.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/chipidea.h>
+
+#include "ci.h"
+#include "bits.h"
+#include "otg.h"
+
+/**
+ * ci_otg_role - pick role based on ID pin state
+ * @ci: the controller
+ */
+enum ci_role ci_otg_role(struct ci_hdrc *ci)
+{
+	u32 sts = hw_read(ci, OP_OTGSC, ~0);
+	enum ci_role role = sts & OTGSC_ID
+		? CI_ROLE_GADGET
+		: CI_ROLE_HOST;
+
+	return role;
+}
+
+void ci_handle_vbus_change(struct ci_hdrc *ci)
+{
+	u32 otgsc;
+
+	if (!ci->is_otg)
+		return;
+
+	otgsc = hw_read(ci, OP_OTGSC, ~0);
+
+	if (otgsc & OTGSC_BSV)
+		usb_gadget_vbus_connect(&ci->gadget);
+	else
+		usb_gadget_vbus_disconnect(&ci->gadget);
+}
+
+#define CI_VBUS_STABLE_TIMEOUT_MS 5000
+static void ci_handle_id_switch(struct ci_hdrc *ci)
+{
+	enum ci_role role = ci_otg_role(ci);
+
+	if (role != ci->role) {
+		dev_dbg(ci->dev, "switching from %s to %s\n",
+			ci_role(ci)->name, ci->roles[role]->name);
+
+		ci_role_stop(ci);
+		/* wait vbus lower than OTGSC_BSV */
+		hw_wait_reg(ci, OP_OTGSC, OTGSC_BSV, 0,
+				CI_VBUS_STABLE_TIMEOUT_MS);
+		ci_role_start(ci, role);
+	}
+}
+/**
+ * ci_otg_work - perform otg (vbus/id) event handle
+ * @work: work struct
+ */
+static void ci_otg_work(struct work_struct *work)
+{
+	struct ci_hdrc *ci = container_of(work, struct ci_hdrc, work);
+
+	if (ci->id_event) {
+		ci->id_event = false;
+		ci_handle_id_switch(ci);
+	} else if (ci->b_sess_valid_event) {
+		ci->b_sess_valid_event = false;
+		ci_handle_vbus_change(ci);
+	} else
+		dev_err(ci->dev, "unexpected event occurs at %s\n", __func__);
+
+	enable_irq(ci->irq);
+}
+
+
+/**
+ * ci_hdrc_otg_init - initialize otg struct
+ * ci: the controller
+ */
+int ci_hdrc_otg_init(struct ci_hdrc *ci)
+{
+	INIT_WORK(&ci->work, ci_otg_work);
+	ci->wq = create_singlethread_workqueue("ci_otg");
+	if (!ci->wq) {
+		dev_err(ci->dev, "can't create workqueue\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+/**
+ * ci_hdrc_otg_destroy - destroy otg struct
+ * ci: the controller
+ */
+void ci_hdrc_otg_destroy(struct ci_hdrc *ci)
+{
+	if (ci->wq) {
+		flush_workqueue(ci->wq);
+		destroy_workqueue(ci->wq);
+	}
+	ci_disable_otg_interrupt(ci, OTGSC_INT_EN_BITS);
+	ci_clear_otg_interrupt(ci, OTGSC_INT_STATUS_BITS);
+}