USB: OTG: add Marvell usb OTG driver support

This driver is for ChipIdea USB OTG controller on Marvell Socs.
PXA9xx/MMP2/MMP3/MGx all have this USB OTG controller.
Signed-off-by: Neil Zhang <zhangwm@marvell.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/otg/Kconfig

@@ -130,4 +130,16 @@ config FSL_USB2_OTG
 	help
 	  Enable this to support Freescale USB OTG transceiver.
 
+config USB_MV_OTG
+	tristate "Marvell USB OTG support"
+	depends on USB_MV_UDC
+	select USB_OTG
+	select USB_OTG_UTILS
+	help
+	  Say Y here if you want to build Marvell USB OTG transciever
+	  driver in kernel (including PXA and MMP series). This driver
+	  implements role switch between EHCI host driver and gadget driver.
+
+	  To compile this driver as a module, choose M here.
+
 endif # USB || OTG

drivers/usb/otg/Makefile

@@ -21,3 +21,4 @@ obj-$(CONFIG_USB_MSM_OTG)	+= msm_otg.o
 obj-$(CONFIG_AB8500_USB)	+= ab8500-usb.o
 fsl_usb2_otg-objs		:= fsl_otg.o otg_fsm.o
 obj-$(CONFIG_FSL_USB2_OTG)	+= fsl_usb2_otg.o
+obj-$(CONFIG_USB_MV_OTG)	+= mv_otg.o

drivers/usb/otg/mv_otg.c

+/*
+ * Copyright (C) 2011 Marvell International Ltd. All rights reserved.
+ * Author: Chao Xie <chao.xie@marvell.com>
+ *	   Neil Zhang <zhangwm@marvell.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/device.h>
+#include <linux/proc_fs.h>
+#include <linux/clk.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+
+#include <linux/usb.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/hcd.h>
+#include <linux/platform_data/mv_usb.h>
+
+#include "mv_otg.h"
+
+#define	DRIVER_DESC	"Marvell USB OTG transceiver driver"
+#define	DRIVER_VERSION	"Jan 20, 2010"
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+
+static const char driver_name[] = "mv-otg";
+
+static char *state_string[] = {
+	"undefined",
+	"b_idle",
+	"b_srp_init",
+	"b_peripheral",
+	"b_wait_acon",
+	"b_host",
+	"a_idle",
+	"a_wait_vrise",
+	"a_wait_bcon",
+	"a_host",
+	"a_suspend",
+	"a_peripheral",
+	"a_wait_vfall",
+	"a_vbus_err"
+};
+
+static int mv_otg_set_vbus(struct otg_transceiver *otg, bool on)
+{
+	struct mv_otg *mvotg = container_of(otg, struct mv_otg, otg);
+	if (mvotg->pdata->set_vbus == NULL)
+		return -ENODEV;
+
+	return mvotg->pdata->set_vbus(on);
+}
+
+static int mv_otg_set_host(struct otg_transceiver *otg,
+			   struct usb_bus *host)
+{
+	otg->host = host;
+
+	return 0;
+}
+
+static int mv_otg_set_peripheral(struct otg_transceiver *otg,
+				 struct usb_gadget *gadget)
+{
+	otg->gadget = gadget;
+
+	return 0;
+}
+
+static void mv_otg_run_state_machine(struct mv_otg *mvotg,
+				     unsigned long delay)
+{
+	dev_dbg(&mvotg->pdev->dev, "transceiver is updated\n");
+	if (!mvotg->qwork)
+		return;
+
+	queue_delayed_work(mvotg->qwork, &mvotg->work, delay);
+}
+
+static void mv_otg_timer_await_bcon(unsigned long data)
+{
+	struct mv_otg *mvotg = (struct mv_otg *) data;
+
+	mvotg->otg_ctrl.a_wait_bcon_timeout = 1;
+
+	dev_info(&mvotg->pdev->dev, "B Device No Response!\n");
+
+	if (spin_trylock(&mvotg->wq_lock)) {
+		mv_otg_run_state_machine(mvotg, 0);
+		spin_unlock(&mvotg->wq_lock);
+	}
+}
+
+static int mv_otg_cancel_timer(struct mv_otg *mvotg, unsigned int id)
+{
+	struct timer_list *timer;
+
+	if (id >= OTG_TIMER_NUM)
+		return -EINVAL;
+
+	timer = &mvotg->otg_ctrl.timer[id];
+
+	if (timer_pending(timer))
+		del_timer(timer);
+
+	return 0;
+}
+
+static int mv_otg_set_timer(struct mv_otg *mvotg, unsigned int id,
+			    unsigned long interval,
+			    void (*callback) (unsigned long))
+{
+	struct timer_list *timer;
+
+	if (id >= OTG_TIMER_NUM)
+		return -EINVAL;
+
+	timer = &mvotg->otg_ctrl.timer[id];
+	if (timer_pending(timer)) {
+		dev_err(&mvotg->pdev->dev, "Timer%d is already running\n", id);
+		return -EBUSY;
+	}
+
+	init_timer(timer);
+	timer->data = (unsigned long) mvotg;
+	timer->function = callback;
+	timer->expires = jiffies + interval;
+	add_timer(timer);
+
+	return 0;
+}
+
+static int mv_otg_reset(struct mv_otg *mvotg)
+{
+	unsigned int loops;
+	u32 tmp;
+
+	/* Stop the controller */
+	tmp = readl(&mvotg->op_regs->usbcmd);
+	tmp &= ~USBCMD_RUN_STOP;
+	writel(tmp, &mvotg->op_regs->usbcmd);
+
+	/* Reset the controller to get default values */
+	writel(USBCMD_CTRL_RESET, &mvotg->op_regs->usbcmd);
+
+	loops = 500;
+	while (readl(&mvotg->op_regs->usbcmd) & USBCMD_CTRL_RESET) {
+		if (loops == 0) {
+			dev_err(&mvotg->pdev->dev,
+				"Wait for RESET completed TIMEOUT\n");
+			return -ETIMEDOUT;
+		}
+		loops--;
+		udelay(20);
+	}
+
+	writel(0x0, &mvotg->op_regs->usbintr);
+	tmp = readl(&mvotg->op_regs->usbsts);
+	writel(tmp, &mvotg->op_regs->usbsts);
+
+	return 0;
+}
+
+static void mv_otg_init_irq(struct mv_otg *mvotg)
+{
+	u32 otgsc;
+
+	mvotg->irq_en = OTGSC_INTR_A_SESSION_VALID
+	    | OTGSC_INTR_A_VBUS_VALID;
+	mvotg->irq_status = OTGSC_INTSTS_A_SESSION_VALID
+	    | OTGSC_INTSTS_A_VBUS_VALID;
+
+	if (mvotg->pdata->vbus == NULL) {
+		mvotg->irq_en |= OTGSC_INTR_B_SESSION_VALID
+		    | OTGSC_INTR_B_SESSION_END;
+		mvotg->irq_status |= OTGSC_INTSTS_B_SESSION_VALID
+		    | OTGSC_INTSTS_B_SESSION_END;
+	}
+
+	if (mvotg->pdata->id == NULL) {
+		mvotg->irq_en |= OTGSC_INTR_USB_ID;
+		mvotg->irq_status |= OTGSC_INTSTS_USB_ID;
+	}
+
+	otgsc = readl(&mvotg->op_regs->otgsc);
+	otgsc |= mvotg->irq_en;
+	writel(otgsc, &mvotg->op_regs->otgsc);
+}
+
+static void mv_otg_start_host(struct mv_otg *mvotg, int on)
+{
+	struct otg_transceiver *otg = &mvotg->otg;
+	struct usb_hcd *hcd;
+
+	if (!otg->host)
+		return;
+
+	dev_info(&mvotg->pdev->dev, "%s host\n", on ? "start" : "stop");
+
+	hcd = bus_to_hcd(otg->host);
+
+	if (on)
+		usb_add_hcd(hcd, hcd->irq, IRQF_SHARED);
+	else
+		usb_remove_hcd(hcd);
+}
+
+static void mv_otg_start_periphrals(struct mv_otg *mvotg, int on)
+{
+	struct otg_transceiver *otg = &mvotg->otg;
+
+	if (!otg->gadget)
+		return;
+
+	dev_info(otg->dev, "gadget %s\n", on ? "on" : "off");
+
+	if (on)
+		usb_gadget_vbus_connect(otg->gadget);
+	else
+		usb_gadget_vbus_disconnect(otg->gadget);
+}
+
+static void otg_clock_enable(struct mv_otg *mvotg)
+{
+	unsigned int i;
+
+	for (i = 0; i < mvotg->clknum; i++)
+		clk_enable(mvotg->clk[i]);
+}
+
+static void otg_clock_disable(struct mv_otg *mvotg)
+{
+	unsigned int i;
+
+	for (i = 0; i < mvotg->clknum; i++)
+		clk_disable(mvotg->clk[i]);
+}
+
+static int mv_otg_enable_internal(struct mv_otg *mvotg)
+{
+	int retval = 0;
+
+	if (mvotg->active)
+		return 0;
+
+	dev_dbg(&mvotg->pdev->dev, "otg enabled\n");
+
+	otg_clock_enable(mvotg);
+	if (mvotg->pdata->phy_init) {
+		retval = mvotg->pdata->phy_init(mvotg->phy_regs);
+		if (retval) {
+			dev_err(&mvotg->pdev->dev,
+				"init phy error %d\n", retval);
+			otg_clock_disable(mvotg);
+			return retval;
+		}
+	}
+	mvotg->active = 1;
+
+	return 0;
+
+}
+
+static int mv_otg_enable(struct mv_otg *mvotg)
+{
+	if (mvotg->clock_gating)
+		return mv_otg_enable_internal(mvotg);
+
+	return 0;
+}
+
+static void mv_otg_disable_internal(struct mv_otg *mvotg)
+{
+	if (mvotg->active) {
+		dev_dbg(&mvotg->pdev->dev, "otg disabled\n");
+		if (mvotg->pdata->phy_deinit)
+			mvotg->pdata->phy_deinit(mvotg->phy_regs);
+		otg_clock_disable(mvotg);
+		mvotg->active = 0;
+	}
+}
+
+static void mv_otg_disable(struct mv_otg *mvotg)
+{
+	if (mvotg->clock_gating)
+		mv_otg_disable_internal(mvotg);
+}
+
+static void mv_otg_update_inputs(struct mv_otg *mvotg)
+{
+	struct mv_otg_ctrl *otg_ctrl = &mvotg->otg_ctrl;
+	u32 otgsc;
+
+	otgsc = readl(&mvotg->op_regs->otgsc);
+
+	if (mvotg->pdata->vbus) {
+		if (mvotg->pdata->vbus->poll() == VBUS_HIGH) {
+			otg_ctrl->b_sess_vld = 1;
+			otg_ctrl->b_sess_end = 0;
+		} else {
+			otg_ctrl->b_sess_vld = 0;
+			otg_ctrl->b_sess_end = 1;
+		}
+	} else {
+		otg_ctrl->b_sess_vld = !!(otgsc & OTGSC_STS_B_SESSION_VALID);
+		otg_ctrl->b_sess_end = !!(otgsc & OTGSC_STS_B_SESSION_END);
+	}
+
+	if (mvotg->pdata->id)
+		otg_ctrl->id = !!mvotg->pdata->id->poll();
+	else
+		otg_ctrl->id = !!(otgsc & OTGSC_STS_USB_ID);
+
+	if (mvotg->pdata->otg_force_a_bus_req && !otg_ctrl->id)
+		otg_ctrl->a_bus_req = 1;
+
+	otg_ctrl->a_sess_vld = !!(otgsc & OTGSC_STS_A_SESSION_VALID);
+	otg_ctrl->a_vbus_vld = !!(otgsc & OTGSC_STS_A_VBUS_VALID);
+
+	dev_dbg(&mvotg->pdev->dev, "%s: ", __func__);
+	dev_dbg(&mvotg->pdev->dev, "id %d\n", otg_ctrl->id);
+	dev_dbg(&mvotg->pdev->dev, "b_sess_vld %d\n", otg_ctrl->b_sess_vld);
+	dev_dbg(&mvotg->pdev->dev, "b_sess_end %d\n", otg_ctrl->b_sess_end);
+	dev_dbg(&mvotg->pdev->dev, "a_vbus_vld %d\n", otg_ctrl->a_vbus_vld);
+	dev_dbg(&mvotg->pdev->dev, "a_sess_vld %d\n", otg_ctrl->a_sess_vld);
+}
+
+static void mv_otg_update_state(struct mv_otg *mvotg)
+{
+	struct mv_otg_ctrl *otg_ctrl = &mvotg->otg_ctrl;
+	struct otg_transceiver *otg = &mvotg->otg;
+	int old_state = otg->state;
+
+	switch (old_state) {
+	case OTG_STATE_UNDEFINED:
+		otg->state = OTG_STATE_B_IDLE;
+		/* FALL THROUGH */
+	case OTG_STATE_B_IDLE:
+		if (otg_ctrl->id == 0)
+			otg->state = OTG_STATE_A_IDLE;
+		else if (otg_ctrl->b_sess_vld)
+			otg->state = OTG_STATE_B_PERIPHERAL;
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		if (!otg_ctrl->b_sess_vld || otg_ctrl->id == 0)
+			otg->state = OTG_STATE_B_IDLE;
+		break;
+	case OTG_STATE_A_IDLE:
+		if (otg_ctrl->id)
+			otg->state = OTG_STATE_B_IDLE;
+		else if (!(otg_ctrl->a_bus_drop) &&
+			 (otg_ctrl->a_bus_req || otg_ctrl->a_srp_det))
+			otg->state = OTG_STATE_A_WAIT_VRISE;
+		break;
+	case OTG_STATE_A_WAIT_VRISE:
+		if (otg_ctrl->a_vbus_vld)
+			otg->state = OTG_STATE_A_WAIT_BCON;
+		break;
+	case OTG_STATE_A_WAIT_BCON:
+		if (otg_ctrl->id || otg_ctrl->a_bus_drop
+		    || otg_ctrl->a_wait_bcon_timeout) {
+			mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
+			mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
+			otg->state = OTG_STATE_A_WAIT_VFALL;
+			otg_ctrl->a_bus_req = 0;
+		} else if (!otg_ctrl->a_vbus_vld) {
+			mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
+			mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
+			otg->state = OTG_STATE_A_VBUS_ERR;
+		} else if (otg_ctrl->b_conn) {
+			mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
+			mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
+			otg->state = OTG_STATE_A_HOST;
+		}
+		break;
+	case OTG_STATE_A_HOST:
+		if (otg_ctrl->id || !otg_ctrl->b_conn
+		    || otg_ctrl->a_bus_drop)
+			otg->state = OTG_STATE_A_WAIT_BCON;
+		else if (!otg_ctrl->a_vbus_vld)
+			otg->state = OTG_STATE_A_VBUS_ERR;
+		break;
+	case OTG_STATE_A_WAIT_VFALL:
+		if (otg_ctrl->id
+		    || (!otg_ctrl->b_conn && otg_ctrl->a_sess_vld)
+		    || otg_ctrl->a_bus_req)
+			otg->state = OTG_STATE_A_IDLE;
+		break;
+	case OTG_STATE_A_VBUS_ERR:
+		if (otg_ctrl->id || otg_ctrl->a_clr_err
+		    || otg_ctrl->a_bus_drop) {
+			otg_ctrl->a_clr_err = 0;
+			otg->state = OTG_STATE_A_WAIT_VFALL;
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+static void mv_otg_work(struct work_struct *work)
+{
+	struct mv_otg *mvotg;
+	struct otg_transceiver *otg;
+	int old_state;
+
+	mvotg = container_of((struct delayed_work *)work, struct mv_otg, work);
+
+run:
+	/* work queue is single thread, or we need spin_lock to protect */
+	otg = &mvotg->otg;
+	old_state = otg->state;
+
+	if (!mvotg->active)
+		return;
+
+	mv_otg_update_inputs(mvotg);
+	mv_otg_update_state(mvotg);
+
+	if (old_state != otg->state) {
+		dev_info(&mvotg->pdev->dev, "change from state %s to %s\n",
+			 state_string[old_state],
+			 state_string[otg->state]);
+
+		switch (otg->state) {
+		case OTG_STATE_B_IDLE:
+			mvotg->otg.default_a = 0;
+			if (old_state == OTG_STATE_B_PERIPHERAL)
+				mv_otg_start_periphrals(mvotg, 0);
+			mv_otg_reset(mvotg);
+			mv_otg_disable(mvotg);
+			break;
+		case OTG_STATE_B_PERIPHERAL:
+			mv_otg_enable(mvotg);
+			mv_otg_start_periphrals(mvotg, 1);
+			break;
+		case OTG_STATE_A_IDLE:
+			mvotg->otg.default_a = 1;
+			mv_otg_enable(mvotg);
+			if (old_state == OTG_STATE_A_WAIT_VFALL)
+				mv_otg_start_host(mvotg, 0);
+			mv_otg_reset(mvotg);
+			break;
+		case OTG_STATE_A_WAIT_VRISE:
+			mv_otg_set_vbus(&mvotg->otg, 1);
+			break;
+		case OTG_STATE_A_WAIT_BCON:
+			if (old_state != OTG_STATE_A_HOST)
+				mv_otg_start_host(mvotg, 1);
+			mv_otg_set_timer(mvotg, A_WAIT_BCON_TIMER,
+					 T_A_WAIT_BCON,
+					 mv_otg_timer_await_bcon);
+			/*
+			 * Now, we directly enter A_HOST. So set b_conn = 1
+			 * here. In fact, it need host driver to notify us.
+			 */
+			mvotg->otg_ctrl.b_conn = 1;
+			break;
+		case OTG_STATE_A_HOST:
+			break;
+		case OTG_STATE_A_WAIT_VFALL:
+			/*
+			 * Now, we has exited A_HOST. So set b_conn = 0
+			 * here. In fact, it need host driver to notify us.
+			 */
+			mvotg->otg_ctrl.b_conn = 0;
+			mv_otg_set_vbus(&mvotg->otg, 0);
+			break;
+		case OTG_STATE_A_VBUS_ERR:
+			break;
+		default:
+			break;
+		}
+		goto run;
+	}
+}
+
+static irqreturn_t mv_otg_irq(int irq, void *dev)
+{
+	struct mv_otg *mvotg = dev;
+	u32 otgsc;
+
+	otgsc = readl(&mvotg->op_regs->otgsc);
+	writel(otgsc, &mvotg->op_regs->otgsc);
+
+	/*
+	 * if we have vbus, then the vbus detection for B-device
+	 * will be done by mv_otg_inputs_irq().
+	 */
+	if (mvotg->pdata->vbus)
+		if ((otgsc & OTGSC_STS_USB_ID) &&
+		    !(otgsc & OTGSC_INTSTS_USB_ID))
+			return IRQ_NONE;
+
+	if ((otgsc & mvotg->irq_status) == 0)
+		return IRQ_NONE;
+
+	mv_otg_run_state_machine(mvotg, 0);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t mv_otg_inputs_irq(int irq, void *dev)
+{
+	struct mv_otg *mvotg = dev;
+
+	/* The clock may disabled at this time */
+	if (!mvotg->active) {
+		mv_otg_enable(mvotg);
+		mv_otg_init_irq(mvotg);
+	}
+
+	mv_otg_run_state_machine(mvotg, 0);
+
+	return IRQ_HANDLED;
+}
+
+static ssize_t
+get_a_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct mv_otg *mvotg = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%d\n",
+			 mvotg->otg_ctrl.a_bus_req);
+}
+
+static ssize_t
+set_a_bus_req(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	struct mv_otg *mvotg = dev_get_drvdata(dev);
+
+	if (count > 2)
+		return -1;
+
+	/* We will use this interface to change to A device */
+	if (mvotg->otg.state != OTG_STATE_B_IDLE
+	    && mvotg->otg.state != OTG_STATE_A_IDLE)
+		return -1;
+
+	/* The clock may disabled and we need to set irq for ID detected */
+	mv_otg_enable(mvotg);
+	mv_otg_init_irq(mvotg);
+
+	if (buf[0] == '1') {
+		mvotg->otg_ctrl.a_bus_req = 1;
+		mvotg->otg_ctrl.a_bus_drop = 0;
+		dev_dbg(&mvotg->pdev->dev,
+			"User request: a_bus_req = 1\n");
+
+		if (spin_trylock(&mvotg->wq_lock)) {
+			mv_otg_run_state_machine(mvotg, 0);
+			spin_unlock(&mvotg->wq_lock);
+		}
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR(a_bus_req, S_IRUGO | S_IWUSR, get_a_bus_req,
+		   set_a_bus_req);
+
+static ssize_t
+set_a_clr_err(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	struct mv_otg *mvotg = dev_get_drvdata(dev);
+	if (!mvotg->otg.default_a)
+		return -1;
+
+	if (count > 2)
+		return -1;
+
+	if (buf[0] == '1') {
+		mvotg->otg_ctrl.a_clr_err = 1;
+		dev_dbg(&mvotg->pdev->dev,
+			"User request: a_clr_err = 1\n");
+	}
+
+	if (spin_trylock(&mvotg->wq_lock)) {
+		mv_otg_run_state_machine(mvotg, 0);
+		spin_unlock(&mvotg->wq_lock);
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR(a_clr_err, S_IWUSR, NULL, set_a_clr_err);
+
+static ssize_t
+get_a_bus_drop(struct device *dev, struct device_attribute *attr,
+	       char *buf)
+{
+	struct mv_otg *mvotg = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%d\n",
+			 mvotg->otg_ctrl.a_bus_drop);
+}
+
+static ssize_t
+set_a_bus_drop(struct device *dev, struct device_attribute *attr,
+	       const char *buf, size_t count)
+{
+	struct mv_otg *mvotg = dev_get_drvdata(dev);
+	if (!mvotg->otg.default_a)
+		return -1;
+
+	if (count > 2)
+		return -1;
+
+	if (buf[0] == '0') {
+		mvotg->otg_ctrl.a_bus_drop = 0;
+		dev_dbg(&mvotg->pdev->dev,
+			"User request: a_bus_drop = 0\n");
+	} else if (buf[0] == '1') {
+		mvotg->otg_ctrl.a_bus_drop = 1;
+		mvotg->otg_ctrl.a_bus_req = 0;
+		dev_dbg(&mvotg->pdev->dev,
+			"User request: a_bus_drop = 1\n");
+		dev_dbg(&mvotg->pdev->dev,
+			"User request: and a_bus_req = 0\n");
+	}
+
+	if (spin_trylock(&mvotg->wq_lock)) {
+		mv_otg_run_state_machine(mvotg, 0);
+		spin_unlock(&mvotg->wq_lock);
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR(a_bus_drop, S_IRUGO | S_IWUSR,
+		   get_a_bus_drop, set_a_bus_drop);
+
+static struct attribute *inputs_attrs[] = {
+	&dev_attr_a_bus_req.attr,
+	&dev_attr_a_clr_err.attr,
+	&dev_attr_a_bus_drop.attr,
+	NULL,
+};
+
+static struct attribute_group inputs_attr_group = {
+	.name = "inputs",
+	.attrs = inputs_attrs,
+};
+
+int mv_otg_remove(struct platform_device *pdev)
+{
+	struct mv_otg *mvotg = platform_get_drvdata(pdev);
+	int clk_i;
+
+	sysfs_remove_group(&mvotg->pdev->dev.kobj, &inputs_attr_group);
+
+	if (mvotg->irq)
+		free_irq(mvotg->irq, mvotg);
+
+	if (mvotg->pdata->vbus)
+		free_irq(mvotg->pdata->vbus->irq, mvotg);
+	if (mvotg->pdata->id)
+		free_irq(mvotg->pdata->id->irq, mvotg);
+
+	if (mvotg->qwork) {
+		flush_workqueue(mvotg->qwork);
+		destroy_workqueue(mvotg->qwork);
+	}
+
+	mv_otg_disable(mvotg);
+
+	if (mvotg->cap_regs)
+		iounmap(mvotg->cap_regs);
+
+	if (mvotg->phy_regs)
+		iounmap(mvotg->phy_regs);
+
+	for (clk_i = 0; clk_i <= mvotg->clknum; clk_i++)
+		clk_put(mvotg->clk[clk_i]);
+
+	otg_set_transceiver(NULL);
+	platform_set_drvdata(pdev, NULL);
+
+	kfree(mvotg);
+
+	return 0;
+}
+
+static int mv_otg_probe(struct platform_device *pdev)
+{
+	struct mv_usb_platform_data *pdata = pdev->dev.platform_data;
+	struct mv_otg *mvotg;
+	struct resource *r;
+	int retval = 0, clk_i, i;
+	size_t size;
+
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "failed to get platform data\n");
+		return -ENODEV;
+	}
+
+	size = sizeof(*mvotg) + sizeof(struct clk *) * pdata->clknum;
+	mvotg = kzalloc(size, GFP_KERNEL);
+	if (!mvotg) {
+		dev_err(&pdev->dev, "failed to allocate memory!\n");
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pdev, mvotg);
+
+	mvotg->pdev = pdev;
+	mvotg->pdata = pdata;
+
+	mvotg->clknum = pdata->clknum;
+	for (clk_i = 0; clk_i < mvotg->clknum; clk_i++) {
+		mvotg->clk[clk_i] = clk_get(&pdev->dev, pdata->clkname[clk_i]);
+		if (IS_ERR(mvotg->clk[clk_i])) {
+			retval = PTR_ERR(mvotg->clk[clk_i]);
+			goto err_put_clk;
+		}
+	}
+
+	mvotg->qwork = create_singlethread_workqueue("mv_otg_queue");
+	if (!mvotg->qwork) {
+		dev_dbg(&pdev->dev, "cannot create workqueue for OTG\n");
+		retval = -ENOMEM;
+		goto err_put_clk;
+	}
+
+	INIT_DELAYED_WORK(&mvotg->work, mv_otg_work);
+
+	/* OTG common part */
+	mvotg->pdev = pdev;
+	mvotg->otg.dev = &pdev->dev;
+	mvotg->otg.label = driver_name;
+	mvotg->otg.set_host = mv_otg_set_host;
+	mvotg->otg.set_peripheral = mv_otg_set_peripheral;
+	mvotg->otg.set_vbus = mv_otg_set_vbus;
+	mvotg->otg.state = OTG_STATE_UNDEFINED;
+
+	for (i = 0; i < OTG_TIMER_NUM; i++)
+		init_timer(&mvotg->otg_ctrl.timer[i]);
+
+	r = platform_get_resource_byname(mvotg->pdev,
+					 IORESOURCE_MEM, "phyregs");
+	if (r == NULL) {
+		dev_err(&pdev->dev, "no phy I/O memory resource defined\n");
+		retval = -ENODEV;
+		goto err_destroy_workqueue;
+	}
+
+	mvotg->phy_regs = ioremap(r->start, resource_size(r));
+	if (mvotg->phy_regs == NULL) {
+		dev_err(&pdev->dev, "failed to map phy I/O memory\n");
+		retval = -EFAULT;
+		goto err_destroy_workqueue;
+	}
+
+	r = platform_get_resource_byname(mvotg->pdev,
+					 IORESOURCE_MEM, "capregs");
+	if (r == NULL) {
+		dev_err(&pdev->dev, "no I/O memory resource defined\n");
+		retval = -ENODEV;
+		goto err_unmap_phyreg;
+	}
+
+	mvotg->cap_regs = ioremap(r->start, resource_size(r));
+	if (mvotg->cap_regs == NULL) {
+		dev_err(&pdev->dev, "failed to map I/O memory\n");
+		retval = -EFAULT;
+		goto err_unmap_phyreg;
+	}
+
+	/* we will acces controller register, so enable the udc controller */
+	retval = mv_otg_enable_internal(mvotg);
+	if (retval) {
+		dev_err(&pdev->dev, "mv otg enable error %d\n", retval);
+		goto err_unmap_capreg;
+	}
+
+	mvotg->op_regs =
+		(struct mv_otg_regs __iomem *) ((unsigned long) mvotg->cap_regs
+			+ (readl(mvotg->cap_regs) & CAPLENGTH_MASK));
+
+	if (pdata->id) {
+		retval = request_threaded_irq(pdata->id->irq, NULL,
+					      mv_otg_inputs_irq,
+					      IRQF_ONESHOT, "id", mvotg);
+		if (retval) {
+			dev_info(&pdev->dev,
+				 "Failed to request irq for ID\n");
+			pdata->id = NULL;
+		}
+	}
+
+	if (pdata->vbus) {
+		mvotg->clock_gating = 1;
+		retval = request_threaded_irq(pdata->vbus->irq, NULL,
+					      mv_otg_inputs_irq,
+					      IRQF_ONESHOT, "vbus", mvotg);
+		if (retval) {
+			dev_info(&pdev->dev,
+				 "Failed to request irq for VBUS, "
+				 "disable clock gating\n");
+			mvotg->clock_gating = 0;
+			pdata->vbus = NULL;
+		}
+	}
+
+	if (pdata->disable_otg_clock_gating)
+		mvotg->clock_gating = 0;
+
+	mv_otg_reset(mvotg);
+	mv_otg_init_irq(mvotg);
+
+	r = platform_get_resource(mvotg->pdev, IORESOURCE_IRQ, 0);
+	if (r == NULL) {
+		dev_err(&pdev->dev, "no IRQ resource defined\n");
+		retval = -ENODEV;
+		goto err_disable_clk;
+	}
+
+	mvotg->irq = r->start;
+	if (request_irq(mvotg->irq, mv_otg_irq, IRQF_SHARED,
+			driver_name, mvotg)) {
+		dev_err(&pdev->dev, "Request irq %d for OTG failed\n",
+			mvotg->irq);
+		mvotg->irq = 0;
+		retval = -ENODEV;
+		goto err_disable_clk;
+	}
+
+	retval = otg_set_transceiver(&mvotg->otg);
+	if (retval < 0) {
+		dev_err(&pdev->dev, "can't register transceiver, %d\n",
+			retval);
+		goto err_free_irq;
+	}
+
+	retval = sysfs_create_group(&pdev->dev.kobj, &inputs_attr_group);
+	if (retval < 0) {
+		dev_dbg(&pdev->dev,
+			"Can't register sysfs attr group: %d\n", retval);
+		goto err_set_transceiver;
+	}
+
+	spin_lock_init(&mvotg->wq_lock);
+	if (spin_trylock(&mvotg->wq_lock)) {
+		mv_otg_run_state_machine(mvotg, 2 * HZ);
+		spin_unlock(&mvotg->wq_lock);
+	}
+
+	dev_info(&pdev->dev,
+		 "successful probe OTG device %s clock gating.\n",
+		 mvotg->clock_gating ? "with" : "without");
+
+	return 0;
+
+err_set_transceiver:
+	otg_set_transceiver(NULL);
+err_free_irq:
+	free_irq(mvotg->irq, mvotg);
+err_disable_clk:
+	if (pdata->vbus)
+		free_irq(pdata->vbus->irq, mvotg);
+	if (pdata->id)
+		free_irq(pdata->id->irq, mvotg);
+	mv_otg_disable_internal(mvotg);
+err_unmap_capreg:
+	iounmap(mvotg->cap_regs);
+err_unmap_phyreg:
+	iounmap(mvotg->phy_regs);
+err_destroy_workqueue:
+	flush_workqueue(mvotg->qwork);
+	destroy_workqueue(mvotg->qwork);
+err_put_clk:
+	for (clk_i--; clk_i >= 0; clk_i--)
+		clk_put(mvotg->clk[clk_i]);
+
+	platform_set_drvdata(pdev, NULL);
+	kfree(mvotg);
+
+	return retval;
+}
+
+#ifdef CONFIG_PM
+static int mv_otg_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct mv_otg *mvotg = platform_get_drvdata(pdev);
+
+	if (mvotg->otg.state != OTG_STATE_B_IDLE) {
+		dev_info(&pdev->dev,
+			 "OTG state is not B_IDLE, it is %d!\n",
+			 mvotg->otg.state);
+		return -EAGAIN;
+	}
+
+	if (!mvotg->clock_gating)
+		mv_otg_disable_internal(mvotg);
+
+	return 0;
+}
+
+static int mv_otg_resume(struct platform_device *pdev)
+{
+	struct mv_otg *mvotg = platform_get_drvdata(pdev);
+	u32 otgsc;
+
+	if (!mvotg->clock_gating) {
+		mv_otg_enable_internal(mvotg);
+
+		otgsc = readl(&mvotg->op_regs->otgsc);
+		otgsc |= mvotg->irq_en;
+		writel(otgsc, &mvotg->op_regs->otgsc);
+
+		if (spin_trylock(&mvotg->wq_lock)) {
+			mv_otg_run_state_machine(mvotg, 0);
+			spin_unlock(&mvotg->wq_lock);
+		}
+	}
+	return 0;
+}
+#endif
+
+static struct platform_driver mv_otg_driver = {
+	.probe = mv_otg_probe,
+	.remove = __exit_p(mv_otg_remove),
+	.driver = {
+		   .owner = THIS_MODULE,
+		   .name = driver_name,
+		   },
+#ifdef CONFIG_PM
+	.suspend = mv_otg_suspend,
+	.resume = mv_otg_resume,
+#endif
+};
+
+static int __init mv_otg_init(void)
+{
+	return platform_driver_register(&mv_otg_driver);
+}
+
+static void __exit mv_otg_exit(void)
+{
+	platform_driver_unregister(&mv_otg_driver);
+}
+
+module_init(mv_otg_init);
+module_exit(mv_otg_exit);

drivers/usb/otg/mv_otg.h

+/*
+ * Copyright (C) 2011 Marvell International Ltd. All rights reserved.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#ifndef	__MV_USB_OTG_CONTROLLER__
+#define	__MV_USB_OTG_CONTROLLER__
+
+#include <linux/types.h>
+
+/* Command Register Bit Masks */
+#define USBCMD_RUN_STOP			(0x00000001)
+#define USBCMD_CTRL_RESET		(0x00000002)
+
+/* otgsc Register Bit Masks */
+#define OTGSC_CTRL_VUSB_DISCHARGE		0x00000001
+#define OTGSC_CTRL_VUSB_CHARGE			0x00000002
+#define OTGSC_CTRL_OTG_TERM			0x00000008
+#define OTGSC_CTRL_DATA_PULSING			0x00000010
+#define OTGSC_STS_USB_ID			0x00000100
+#define OTGSC_STS_A_VBUS_VALID			0x00000200
+#define OTGSC_STS_A_SESSION_VALID		0x00000400
+#define OTGSC_STS_B_SESSION_VALID		0x00000800
+#define OTGSC_STS_B_SESSION_END			0x00001000
+#define OTGSC_STS_1MS_TOGGLE			0x00002000
+#define OTGSC_STS_DATA_PULSING			0x00004000
+#define OTGSC_INTSTS_USB_ID			0x00010000
+#define OTGSC_INTSTS_A_VBUS_VALID		0x00020000
+#define OTGSC_INTSTS_A_SESSION_VALID		0x00040000
+#define OTGSC_INTSTS_B_SESSION_VALID		0x00080000
+#define OTGSC_INTSTS_B_SESSION_END		0x00100000
+#define OTGSC_INTSTS_1MS			0x00200000
+#define OTGSC_INTSTS_DATA_PULSING		0x00400000
+#define OTGSC_INTR_USB_ID			0x01000000
+#define OTGSC_INTR_A_VBUS_VALID			0x02000000
+#define OTGSC_INTR_A_SESSION_VALID		0x04000000
+#define OTGSC_INTR_B_SESSION_VALID		0x08000000
+#define OTGSC_INTR_B_SESSION_END		0x10000000
+#define OTGSC_INTR_1MS_TIMER			0x20000000
+#define OTGSC_INTR_DATA_PULSING			0x40000000
+
+#define CAPLENGTH_MASK		(0xff)
+
+/* Timer's interval, unit 10ms */
+#define T_A_WAIT_VRISE		100
+#define T_A_WAIT_BCON		2000
+#define T_A_AIDL_BDIS		100
+#define T_A_BIDL_ADIS		20
+#define T_B_ASE0_BRST		400
+#define T_B_SE0_SRP		300
+#define T_B_SRP_FAIL		2000
+#define T_B_DATA_PLS		10
+#define T_B_SRP_INIT		100
+#define T_A_SRP_RSPNS		10
+#define T_A_DRV_RSM		5
+
+enum otg_function {
+	OTG_B_DEVICE = 0,
+	OTG_A_DEVICE
+};
+
+enum mv_otg_timer {
+	A_WAIT_BCON_TIMER = 0,
+	OTG_TIMER_NUM
+};
+
+/* PXA OTG state machine */
+struct mv_otg_ctrl {
+	/* internal variables */
+	u8 a_set_b_hnp_en;	/* A-Device set b_hnp_en */
+	u8 b_srp_done;
+	u8 b_hnp_en;
+
+	/* OTG inputs */
+	u8 a_bus_drop;
+	u8 a_bus_req;
+	u8 a_clr_err;
+	u8 a_bus_resume;
+	u8 a_bus_suspend;
+	u8 a_conn;
+	u8 a_sess_vld;
+	u8 a_srp_det;
+	u8 a_vbus_vld;
+	u8 b_bus_req;		/* B-Device Require Bus */
+	u8 b_bus_resume;
+	u8 b_bus_suspend;
+	u8 b_conn;
+	u8 b_se0_srp;
+	u8 b_sess_end;
+	u8 b_sess_vld;
+	u8 id;
+	u8 a_suspend_req;
+
+	/*Timer event */
+	u8 a_aidl_bdis_timeout;
+	u8 b_ase0_brst_timeout;
+	u8 a_bidl_adis_timeout;
+	u8 a_wait_bcon_timeout;
+
+	struct timer_list timer[OTG_TIMER_NUM];
+};
+
+#define VUSBHS_MAX_PORTS	8
+
+struct mv_otg_regs {
+	u32 usbcmd;		/* Command register */
+	u32 usbsts;		/* Status register */
+	u32 usbintr;		/* Interrupt enable */
+	u32 frindex;		/* Frame index */
+	u32 reserved1[1];
+	u32 deviceaddr;		/* Device Address */
+	u32 eplistaddr;		/* Endpoint List Address */
+	u32 ttctrl;		/* HOST TT status and control */
+	u32 burstsize;		/* Programmable Burst Size */
+	u32 txfilltuning;	/* Host Transmit Pre-Buffer Packet Tuning */
+	u32 reserved[4];
+	u32 epnak;		/* Endpoint NAK */
+	u32 epnaken;		/* Endpoint NAK Enable */
+	u32 configflag;		/* Configured Flag register */
+	u32 portsc[VUSBHS_MAX_PORTS];	/* Port Status/Control x, x = 1..8 */
+	u32 otgsc;
+	u32 usbmode;		/* USB Host/Device mode */
+	u32 epsetupstat;	/* Endpoint Setup Status */
+	u32 epprime;		/* Endpoint Initialize */
+	u32 epflush;		/* Endpoint De-initialize */
+	u32 epstatus;		/* Endpoint Status */
+	u32 epcomplete;		/* Endpoint Interrupt On Complete */
+	u32 epctrlx[16];	/* Endpoint Control, where x = 0.. 15 */
+	u32 mcr;		/* Mux Control */
+	u32 isr;		/* Interrupt Status */
+	u32 ier;		/* Interrupt Enable */
+};
+
+struct mv_otg {
+	struct otg_transceiver otg;
+	struct mv_otg_ctrl otg_ctrl;
+
+	/* base address */
+	void __iomem *phy_regs;
+	void __iomem *cap_regs;
+	struct mv_otg_regs __iomem *op_regs;
+
+	struct platform_device *pdev;
+	int irq;
+	u32 irq_status;
+	u32 irq_en;
+
+	struct delayed_work work;
+	struct workqueue_struct *qwork;
+
+	spinlock_t wq_lock;
+
+	struct mv_usb_platform_data *pdata;
+
+	unsigned int active;
+	unsigned int clock_gating;
+	unsigned int clknum;
+	struct clk *clk[0];
+};
+
+#endif

include/linux/platform_data/mv_usb.h

@@ -42,6 +42,11 @@ struct mv_usb_platform_data {
 	/* only valid for HCD. OTG or Host only*/
 	unsigned int		mode;
 
+	/* This flag is used for that needs id pin checked by otg */
+	unsigned int    disable_otg_clock_gating:1;
+	/* Force a_bus_req to be asserted */
+	 unsigned int    otg_force_a_bus_req:1;
+
 	int	(*phy_init)(void __iomem *regbase);
 	void	(*phy_deinit)(void __iomem *regbase);
 	int	(*set_vbus)(unsigned int vbus);