USB: add Freescale USB OTG Transceiver driver

Slightly reworked and cleaned up driver from Freescale LTIB
for MPC5121E. The driver has been ported to the current kernel,
proc interface "/proc/driver/fsl_usb2_otg" has been replaced by
sysfs interface.

Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1169 insertions, 0 deletions

diff --git a/drivers/usb/otg/fsl_otg.c b/drivers/usb/otg/fsl_otg.c
new file mode 100644
index 000000000000..0f420b25e9a9
--- /dev/null
+++ b/drivers/usb/otg/fsl_otg.c
@@ -0,0 +1,1169 @@
+/*
+ * Copyright (C) 2007,2008 Freescale semiconductor, Inc.
+ *
+ * Author: Li Yang <LeoLi@freescale.com>
+ *         Jerry Huang <Chang-Ming.Huang@freescale.com>
+ *
+ * Initialization based on code from Shlomi Gridish.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the  GNU General Public License along
+ * with this program; if not, write  to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/proc_fs.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/timer.h>
+#include <linux/usb.h>
+#include <linux/device.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/workqueue.h>
+#include <linux/time.h>
+#include <linux/fsl_devices.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+
+#include <asm/unaligned.h>
+
+#include "fsl_otg.h"
+
+#define DRIVER_VERSION "Rev. 1.55"
+#define DRIVER_AUTHOR "Jerry Huang/Li Yang"
+#define DRIVER_DESC "Freescale USB OTG Transceiver Driver"
+#define DRIVER_INFO DRIVER_DESC " " DRIVER_VERSION
+
+static const char driver_name[] = "fsl-usb2-otg";
+
+const pm_message_t otg_suspend_state = {
+	.event = 1,
+};
+
+#define HA_DATA_PULSE
+
+static struct usb_dr_mmap *usb_dr_regs;
+static struct fsl_otg *fsl_otg_dev;
+static int srp_wait_done;
+
+/* FSM timers */
+struct fsl_otg_timer *a_wait_vrise_tmr, *a_wait_bcon_tmr, *a_aidl_bdis_tmr,
+	*b_ase0_brst_tmr, *b_se0_srp_tmr;
+
+/* Driver specific timers */
+struct fsl_otg_timer *b_data_pulse_tmr, *b_vbus_pulse_tmr, *b_srp_fail_tmr,
+	*b_srp_wait_tmr, *a_wait_enum_tmr;
+
+static struct list_head active_timers;
+
+static struct fsl_otg_config fsl_otg_initdata = {
+	.otg_port = 1,
+};
+
+#ifdef CONFIG_PPC32
+static u32 _fsl_readl_be(const unsigned __iomem *p)
+{
+	return in_be32(p);
+}
+
+static u32 _fsl_readl_le(const unsigned __iomem *p)
+{
+	return in_le32(p);
+}
+
+static void _fsl_writel_be(u32 v, unsigned __iomem *p)
+{
+	out_be32(p, v);
+}
+
+static void _fsl_writel_le(u32 v, unsigned __iomem *p)
+{
+	out_le32(p, v);
+}
+
+static u32 (*_fsl_readl)(const unsigned __iomem *p);
+static void (*_fsl_writel)(u32 v, unsigned __iomem *p);
+
+#define fsl_readl(p)		(*_fsl_readl)((p))
+#define fsl_writel(v, p)	(*_fsl_writel)((v), (p))
+
+#else
+#define fsl_readl(addr)		readl(addr)
+#define fsl_writel(val, addr)	writel(val, addr)
+#endif /* CONFIG_PPC32 */
+
+/* Routines to access transceiver ULPI registers */
+u8 view_ulpi(u8 addr)
+{
+	u32 temp;
+
+	temp = 0x40000000 | (addr << 16);
+	fsl_writel(temp, &usb_dr_regs->ulpiview);
+	udelay(1000);
+	while (temp & 0x40)
+		temp = fsl_readl(&usb_dr_regs->ulpiview);
+	return (le32_to_cpu(temp) & 0x0000ff00) >> 8;
+}
+
+int write_ulpi(u8 addr, u8 data)
+{
+	u32 temp;
+
+	temp = 0x60000000 | (addr << 16) | data;
+	fsl_writel(temp, &usb_dr_regs->ulpiview);
+	return 0;
+}
+
+/* -------------------------------------------------------------*/
+/* Operations that will be called from OTG Finite State Machine */
+
+/* Charge vbus for vbus pulsing in SRP */
+void fsl_otg_chrg_vbus(int on)
+{
+	u32 tmp;
+
+	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
+
+	if (on)
+		/* stop discharging, start charging */
+		tmp = (tmp & ~OTGSC_CTRL_VBUS_DISCHARGE) |
+			OTGSC_CTRL_VBUS_CHARGE;
+	else
+		/* stop charging */
+		tmp &= ~OTGSC_CTRL_VBUS_CHARGE;
+
+	fsl_writel(tmp, &usb_dr_regs->otgsc);
+}
+
+/* Discharge vbus through a resistor to ground */
+void fsl_otg_dischrg_vbus(int on)
+{
+	u32 tmp;
+
+	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
+
+	if (on)
+		/* stop charging, start discharging */
+		tmp = (tmp & ~OTGSC_CTRL_VBUS_CHARGE) |
+			OTGSC_CTRL_VBUS_DISCHARGE;
+	else
+		/* stop discharging */
+		tmp &= ~OTGSC_CTRL_VBUS_DISCHARGE;
+
+	fsl_writel(tmp, &usb_dr_regs->otgsc);
+}
+
+/* A-device driver vbus, controlled through PP bit in PORTSC */
+void fsl_otg_drv_vbus(int on)
+{
+	u32 tmp;
+
+	if (on) {
+		tmp = fsl_readl(&usb_dr_regs->portsc) & ~PORTSC_W1C_BITS;
+		fsl_writel(tmp | PORTSC_PORT_POWER, &usb_dr_regs->portsc);
+	} else {
+		tmp = fsl_readl(&usb_dr_regs->portsc) &
+		      ~PORTSC_W1C_BITS & ~PORTSC_PORT_POWER;
+		fsl_writel(tmp, &usb_dr_regs->portsc);
+	}
+}
+
+/*
+ * Pull-up D+, signalling connect by periperal. Also used in
+ * data-line pulsing in SRP
+ */
+void fsl_otg_loc_conn(int on)
+{
+	u32 tmp;
+
+	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
+
+	if (on)
+		tmp |= OTGSC_CTRL_DATA_PULSING;
+	else
+		tmp &= ~OTGSC_CTRL_DATA_PULSING;
+
+	fsl_writel(tmp, &usb_dr_regs->otgsc);
+}
+
+/*
+ * Generate SOF by host.  This is controlled through suspend/resume the
+ * port.  In host mode, controller will automatically send SOF.
+ * Suspend will block the data on the port.
+ */
+void fsl_otg_loc_sof(int on)
+{
+	u32 tmp;
+
+	tmp = fsl_readl(&fsl_otg_dev->dr_mem_map->portsc) & ~PORTSC_W1C_BITS;
+	if (on)
+		tmp |= PORTSC_PORT_FORCE_RESUME;
+	else
+		tmp |= PORTSC_PORT_SUSPEND;
+
+	fsl_writel(tmp, &fsl_otg_dev->dr_mem_map->portsc);
+
+}
+
+/* Start SRP pulsing by data-line pulsing, followed with v-bus pulsing. */
+void fsl_otg_start_pulse(void)
+{
+	u32 tmp;
+
+	srp_wait_done = 0;
+#ifdef HA_DATA_PULSE
+	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
+	tmp |= OTGSC_HA_DATA_PULSE;
+	fsl_writel(tmp, &usb_dr_regs->otgsc);
+#else
+	fsl_otg_loc_conn(1);
+#endif
+
+	fsl_otg_add_timer(b_data_pulse_tmr);
+}
+
+void b_data_pulse_end(unsigned long foo)
+{
+#ifdef HA_DATA_PULSE
+#else
+	fsl_otg_loc_conn(0);
+#endif
+
+	/* Do VBUS pulse after data pulse */
+	fsl_otg_pulse_vbus();
+}
+
+void fsl_otg_pulse_vbus(void)
+{
+	srp_wait_done = 0;
+	fsl_otg_chrg_vbus(1);
+	/* start the timer to end vbus charge */
+	fsl_otg_add_timer(b_vbus_pulse_tmr);
+}
+
+void b_vbus_pulse_end(unsigned long foo)
+{
+	fsl_otg_chrg_vbus(0);
+
+	/*
+	 * As USB3300 using the same a_sess_vld and b_sess_vld voltage
+	 * we need to discharge the bus for a while to distinguish
+	 * residual voltage of vbus pulsing and A device pull up
+	 */
+	fsl_otg_dischrg_vbus(1);
+	fsl_otg_add_timer(b_srp_wait_tmr);
+}
+
+void b_srp_end(unsigned long foo)
+{
+	fsl_otg_dischrg_vbus(0);
+	srp_wait_done = 1;
+
+	if ((fsl_otg_dev->otg.state == OTG_STATE_B_SRP_INIT) &&
+	    fsl_otg_dev->fsm.b_sess_vld)
+		fsl_otg_dev->fsm.b_srp_done = 1;
+}
+
+/*
+ * Workaround for a_host suspending too fast.  When a_bus_req=0,
+ * a_host will start by SRP.  It needs to set b_hnp_enable before
+ * actually suspending to start HNP
+ */
+void a_wait_enum(unsigned long foo)
+{
+	VDBG("a_wait_enum timeout\n");
+	if (!fsl_otg_dev->otg.host->b_hnp_enable)
+		fsl_otg_add_timer(a_wait_enum_tmr);
+	else
+		otg_statemachine(&fsl_otg_dev->fsm);
+}
+
+/* The timeout callback function to set time out bit */
+void set_tmout(unsigned long indicator)
+{
+	*(int *)indicator = 1;
+}
+
+/* Initialize timers */
+int fsl_otg_init_timers(struct otg_fsm *fsm)
+{
+	/* FSM used timers */
+	a_wait_vrise_tmr = otg_timer_initializer(&set_tmout, TA_WAIT_VRISE,
+				(unsigned long)&fsm->a_wait_vrise_tmout);
+	if (!a_wait_vrise_tmr)
+		return -ENOMEM;
+
+	a_wait_bcon_tmr = otg_timer_initializer(&set_tmout, TA_WAIT_BCON,
+				(unsigned long)&fsm->a_wait_bcon_tmout);
+	if (!a_wait_bcon_tmr)
+		return -ENOMEM;
+
+	a_aidl_bdis_tmr = otg_timer_initializer(&set_tmout, TA_AIDL_BDIS,
+				(unsigned long)&fsm->a_aidl_bdis_tmout);
+	if (!a_aidl_bdis_tmr)
+		return -ENOMEM;
+
+	b_ase0_brst_tmr = otg_timer_initializer(&set_tmout, TB_ASE0_BRST,
+				(unsigned long)&fsm->b_ase0_brst_tmout);
+	if (!b_ase0_brst_tmr)
+		return -ENOMEM;
+
+	b_se0_srp_tmr = otg_timer_initializer(&set_tmout, TB_SE0_SRP,
+				(unsigned long)&fsm->b_se0_srp);
+	if (!b_se0_srp_tmr)
+		return -ENOMEM;
+
+	b_srp_fail_tmr = otg_timer_initializer(&set_tmout, TB_SRP_FAIL,
+				(unsigned long)&fsm->b_srp_done);
+	if (!b_srp_fail_tmr)
+		return -ENOMEM;
+
+	a_wait_enum_tmr = otg_timer_initializer(&a_wait_enum, 10,
+				(unsigned long)&fsm);
+	if (!a_wait_enum_tmr)
+		return -ENOMEM;
+
+	/* device driver used timers */
+	b_srp_wait_tmr = otg_timer_initializer(&b_srp_end, TB_SRP_WAIT, 0);
+	if (!b_srp_wait_tmr)
+		return -ENOMEM;
+
+	b_data_pulse_tmr = otg_timer_initializer(&b_data_pulse_end,
+				TB_DATA_PLS, 0);
+	if (!b_data_pulse_tmr)
+		return -ENOMEM;
+
+	b_vbus_pulse_tmr = otg_timer_initializer(&b_vbus_pulse_end,
+				TB_VBUS_PLS, 0);
+	if (!b_vbus_pulse_tmr)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/* Uninitialize timers */
+void fsl_otg_uninit_timers(void)
+{
+	/* FSM used timers */
+	if (a_wait_vrise_tmr != NULL)
+		kfree(a_wait_vrise_tmr);
+	if (a_wait_bcon_tmr != NULL)
+		kfree(a_wait_bcon_tmr);
+	if (a_aidl_bdis_tmr != NULL)
+		kfree(a_aidl_bdis_tmr);
+	if (b_ase0_brst_tmr != NULL)
+		kfree(b_ase0_brst_tmr);
+	if (b_se0_srp_tmr != NULL)
+		kfree(b_se0_srp_tmr);
+	if (b_srp_fail_tmr != NULL)
+		kfree(b_srp_fail_tmr);
+	if (a_wait_enum_tmr != NULL)
+		kfree(a_wait_enum_tmr);
+
+	/* device driver used timers */
+	if (b_srp_wait_tmr != NULL)
+		kfree(b_srp_wait_tmr);
+	if (b_data_pulse_tmr != NULL)
+		kfree(b_data_pulse_tmr);
+	if (b_vbus_pulse_tmr != NULL)
+		kfree(b_vbus_pulse_tmr);
+}
+
+/* Add timer to timer list */
+void fsl_otg_add_timer(void *gtimer)
+{
+	struct fsl_otg_timer *timer = gtimer;
+	struct fsl_otg_timer *tmp_timer;
+
+	/*
+	 * Check if the timer is already in the active list,
+	 * if so update timer count
+	 */
+	list_for_each_entry(tmp_timer, &active_timers, list)
+	    if (tmp_timer == timer) {
+		timer->count = timer->expires;
+		return;
+	}
+	timer->count = timer->expires;
+	list_add_tail(&timer->list, &active_timers);
+}
+
+/* Remove timer from the timer list; clear timeout status */
+void fsl_otg_del_timer(void *gtimer)
+{
+	struct fsl_otg_timer *timer = gtimer;
+	struct fsl_otg_timer *tmp_timer, *del_tmp;
+
+	list_for_each_entry_safe(tmp_timer, del_tmp, &active_timers, list)
+		if (tmp_timer == timer)
+			list_del(&timer->list);
+}
+
+/*
+ * Reduce timer count by 1, and find timeout conditions.
+ * Called by fsl_otg 1ms timer interrupt
+ */
+int fsl_otg_tick_timer(void)
+{
+	struct fsl_otg_timer *tmp_timer, *del_tmp;
+	int expired = 0;
+
+	list_for_each_entry_safe(tmp_timer, del_tmp, &active_timers, list) {
+		tmp_timer->count--;
+		/* check if timer expires */
+		if (!tmp_timer->count) {
+			list_del(&tmp_timer->list);
+			tmp_timer->function(tmp_timer->data);
+			expired = 1;
+		}
+	}
+
+	return expired;
+}
+
+/* Reset controller, not reset the bus */
+void otg_reset_controller(void)
+{
+	u32 command;
+
+	command = fsl_readl(&usb_dr_regs->usbcmd);
+	command |= (1 << 1);
+	fsl_writel(command, &usb_dr_regs->usbcmd);
+	while (fsl_readl(&usb_dr_regs->usbcmd) & (1 << 1))
+		;
+}
+
+/* Call suspend/resume routines in host driver */
+int fsl_otg_start_host(struct otg_fsm *fsm, int on)
+{
+	struct otg_transceiver *xceiv = fsm->transceiver;
+	struct device *dev;
+	struct fsl_otg *otg_dev = container_of(xceiv, struct fsl_otg, otg);
+	u32 retval = 0;
+
+	if (!xceiv->host)
+		return -ENODEV;
+	dev = xceiv->host->controller;
+
+	/*
+	 * Update a_vbus_vld state as a_vbus_vld int is disabled
+	 * in device mode
+	 */
+	fsm->a_vbus_vld =
+		!!(fsl_readl(&usb_dr_regs->otgsc) & OTGSC_STS_A_VBUS_VALID);
+	if (on) {
+		/* start fsl usb host controller */
+		if (otg_dev->host_working)
+			goto end;
+		else {
+			otg_reset_controller();
+			VDBG("host on......\n");
+			if (dev->driver->pm && dev->driver->pm->resume) {
+				retval = dev->driver->pm->resume(dev);
+				if (fsm->id) {
+					/* default-b */
+					fsl_otg_drv_vbus(1);
+					/*
+					 * Workaround: b_host can't driver
+					 * vbus, but PP in PORTSC needs to
+					 * be 1 for host to work.
+					 * So we set drv_vbus bit in
+					 * transceiver to 0 thru ULPI.
+					 */
+					write_ulpi(0x0c, 0x20);
+				}
+			}
+
+			otg_dev->host_working = 1;
+		}
+	} else {
+		/* stop fsl usb host controller */
+		if (!otg_dev->host_working)
+			goto end;
+		else {
+			VDBG("host off......\n");
+			if (dev && dev->driver) {
+				if (dev->driver->pm && dev->driver->pm->suspend)
+					retval = dev->driver->pm->suspend(dev);
+				if (fsm->id)
+					/* default-b */
+					fsl_otg_drv_vbus(0);
+			}
+			otg_dev->host_working = 0;
+		}
+	}
+end:
+	return retval;
+}
+
+/*
+ * Call suspend and resume function in udc driver
+ * to stop and start udc driver.
+ */
+int fsl_otg_start_gadget(struct otg_fsm *fsm, int on)
+{
+	struct otg_transceiver *xceiv = fsm->transceiver;
+	struct device *dev;
+
+	if (!xceiv->gadget || !xceiv->gadget->dev.parent)
+		return -ENODEV;
+
+	VDBG("gadget %s\n", on ? "on" : "off");
+	dev = xceiv->gadget->dev.parent;
+
+	if (on) {
+		if (dev->driver->resume)
+			dev->driver->resume(dev);
+	} else {
+		if (dev->driver->suspend)
+			dev->driver->suspend(dev, otg_suspend_state);
+	}
+
+	return 0;
+}
+
+/*
+ * Called by initialization code of host driver.  Register host controller
+ * to the OTG.  Suspend host for OTG role detection.
+ */
+static int fsl_otg_set_host(struct otg_transceiver *otg_p, struct usb_bus *host)
+{
+	struct fsl_otg *otg_dev = container_of(otg_p, struct fsl_otg, otg);
+
+	if (!otg_p || otg_dev != fsl_otg_dev)
+		return -ENODEV;
+
+	otg_p->host = host;
+
+	otg_dev->fsm.a_bus_drop = 0;
+	otg_dev->fsm.a_bus_req = 1;
+
+	if (host) {
+		VDBG("host off......\n");
+
+		otg_p->host->otg_port = fsl_otg_initdata.otg_port;
+		otg_p->host->is_b_host = otg_dev->fsm.id;
+		/*
+		 * must leave time for khubd to finish its thing
+		 * before yanking the host driver out from under it,
+		 * so suspend the host after a short delay.
+		 */
+		otg_dev->host_working = 1;
+		schedule_delayed_work(&otg_dev->otg_event, 100);
+		return 0;
+	} else {
+		/* host driver going away */
+		if (!(fsl_readl(&otg_dev->dr_mem_map->otgsc) &
+		      OTGSC_STS_USB_ID)) {
+			/* Mini-A cable connected */
+			struct otg_fsm *fsm = &otg_dev->fsm;
+
+			otg_p->state = OTG_STATE_UNDEFINED;
+			fsm->protocol = PROTO_UNDEF;
+		}
+	}
+
+	otg_dev->host_working = 0;
+
+	otg_statemachine(&otg_dev->fsm);
+
+	return 0;
+}
+
+/* Called by initialization code of udc.  Register udc to OTG. */
+static int fsl_otg_set_peripheral(struct otg_transceiver *otg_p,
+				  struct usb_gadget *gadget)
+{
+	struct fsl_otg *otg_dev = container_of(otg_p, struct fsl_otg, otg);
+
+	VDBG("otg_dev 0x%x\n", (int)otg_dev);
+	VDBG("fsl_otg_dev 0x%x\n", (int)fsl_otg_dev);
+
+	if (!otg_p || otg_dev != fsl_otg_dev)
+		return -ENODEV;
+
+	if (!gadget) {
+		if (!otg_dev->otg.default_a)
+			otg_p->gadget->ops->vbus_draw(otg_p->gadget, 0);
+		usb_gadget_vbus_disconnect(otg_dev->otg.gadget);
+		otg_dev->otg.gadget = 0;
+		otg_dev->fsm.b_bus_req = 0;
+		otg_statemachine(&otg_dev->fsm);
+		return 0;
+	}
+
+	otg_p->gadget = gadget;
+	otg_p->gadget->is_a_peripheral = !otg_dev->fsm.id;
+
+	otg_dev->fsm.b_bus_req = 1;
+
+	/* start the gadget right away if the ID pin says Mini-B */
+	DBG("ID pin=%d\n", otg_dev->fsm.id);
+	if (otg_dev->fsm.id == 1) {
+		fsl_otg_start_host(&otg_dev->fsm, 0);
+		otg_drv_vbus(&otg_dev->fsm, 0);
+		fsl_otg_start_gadget(&otg_dev->fsm, 1);
+	}
+
+	return 0;
+}
+
+/* Set OTG port power, only for B-device */
+static int fsl_otg_set_power(struct otg_transceiver *otg_p, unsigned mA)
+{
+	if (!fsl_otg_dev)
+		return -ENODEV;
+	if (otg_p->state == OTG_STATE_B_PERIPHERAL)
+		pr_info("FSL OTG: Draw %d mA\n", mA);
+
+	return 0;
+}
+
+/*
+ * Delayed pin detect interrupt processing.
+ *
+ * When the Mini-A cable is disconnected from the board,
+ * the pin-detect interrupt happens before the disconnnect
+ * interrupts for the connected device(s).  In order to
+ * process the disconnect interrupt(s) prior to switching
+ * roles, the pin-detect interrupts are delayed, and handled
+ * by this routine.
+ */
+static void fsl_otg_event(struct work_struct *work)
+{
+	struct fsl_otg *og = container_of(work, struct fsl_otg, otg_event.work);
+	struct otg_fsm *fsm = &og->fsm;
+
+	if (fsm->id) {		/* switch to gadget */
+		fsl_otg_start_host(fsm, 0);
+		otg_drv_vbus(fsm, 0);
+		fsl_otg_start_gadget(fsm, 1);
+	}
+}
+
+/* B-device start SRP */
+static int fsl_otg_start_srp(struct otg_transceiver *otg_p)
+{
+	struct fsl_otg *otg_dev = container_of(otg_p, struct fsl_otg, otg);
+
+	if (!otg_p || otg_dev != fsl_otg_dev
+	    || otg_p->state != OTG_STATE_B_IDLE)
+		return -ENODEV;
+
+	otg_dev->fsm.b_bus_req = 1;
+	otg_statemachine(&otg_dev->fsm);
+
+	return 0;
+}
+
+/* A_host suspend will call this function to start hnp */
+static int fsl_otg_start_hnp(struct otg_transceiver *otg_p)
+{
+	struct fsl_otg *otg_dev = container_of(otg_p, struct fsl_otg, otg);
+
+	if (!otg_p || otg_dev != fsl_otg_dev)
+		return -ENODEV;
+
+	DBG("start_hnp...n");
+
+	/* clear a_bus_req to enter a_suspend state */
+	otg_dev->fsm.a_bus_req = 0;
+	otg_statemachine(&otg_dev->fsm);
+
+	return 0;
+}
+
+/*
+ * Interrupt handler.  OTG/host/peripheral share the same int line.
+ * OTG driver clears OTGSC interrupts and leaves USB interrupts
+ * intact.  It needs to have knowledge of some USB interrupts
+ * such as port change.
+ */
+irqreturn_t fsl_otg_isr(int irq, void *dev_id)
+{
+	struct otg_fsm *fsm = &((struct fsl_otg *)dev_id)->fsm;
+	struct otg_transceiver *otg = &((struct fsl_otg *)dev_id)->otg;
+	u32 otg_int_src, otg_sc;
+
+	otg_sc = fsl_readl(&usb_dr_regs->otgsc);
+	otg_int_src = otg_sc & OTGSC_INTSTS_MASK & (otg_sc >> 8);
+
+	/* Only clear otg interrupts */
+	fsl_writel(otg_sc, &usb_dr_regs->otgsc);
+
+	/*FIXME: ID change not generate when init to 0 */
+	fsm->id = (otg_sc & OTGSC_STS_USB_ID) ? 1 : 0;
+	otg->default_a = (fsm->id == 0);
+
+	/* process OTG interrupts */
+	if (otg_int_src) {
+		if (otg_int_src & OTGSC_INTSTS_USB_ID) {
+			fsm->id = (otg_sc & OTGSC_STS_USB_ID) ? 1 : 0;
+			otg->default_a = (fsm->id == 0);
+			/* clear conn information */
+			if (fsm->id)
+				fsm->b_conn = 0;
+			else
+				fsm->a_conn = 0;
+
+			if (otg->host)
+				otg->host->is_b_host = fsm->id;
+			if (otg->gadget)
+				otg->gadget->is_a_peripheral = !fsm->id;
+			VDBG("ID int (ID is %d)\n", fsm->id);
+
+			if (fsm->id) {	/* switch to gadget */
+				schedule_delayed_work(
+					&((struct fsl_otg *)dev_id)->otg_event,
+					100);
+			} else {	/* switch to host */
+				cancel_delayed_work(&
+						    ((struct fsl_otg *)dev_id)->
+						    otg_event);
+				fsl_otg_start_gadget(fsm, 0);
+				otg_drv_vbus(fsm, 1);
+				fsl_otg_start_host(fsm, 1);
+			}
+			return IRQ_HANDLED;
+		}
+	}
+	return IRQ_NONE;
+}
+
+static struct otg_fsm_ops fsl_otg_ops = {
+	.chrg_vbus = fsl_otg_chrg_vbus,
+	.drv_vbus = fsl_otg_drv_vbus,
+	.loc_conn = fsl_otg_loc_conn,
+	.loc_sof = fsl_otg_loc_sof,
+	.start_pulse = fsl_otg_start_pulse,
+
+	.add_timer = fsl_otg_add_timer,
+	.del_timer = fsl_otg_del_timer,
+
+	.start_host = fsl_otg_start_host,
+	.start_gadget = fsl_otg_start_gadget,
+};
+
+/* Initialize the global variable fsl_otg_dev and request IRQ for OTG */
+static int fsl_otg_conf(struct platform_device *pdev)
+{
+	struct fsl_otg *fsl_otg_tc;
+	int status;
+
+	if (fsl_otg_dev)
+		return 0;
+
+	/* allocate space to fsl otg device */
+	fsl_otg_tc = kzalloc(sizeof(struct fsl_otg), GFP_KERNEL);
+	if (!fsl_otg_tc)
+		return -ENOMEM;
+
+	INIT_DELAYED_WORK(&fsl_otg_tc->otg_event, fsl_otg_event);
+
+	INIT_LIST_HEAD(&active_timers);
+	status = fsl_otg_init_timers(&fsl_otg_tc->fsm);
+	if (status) {
+		pr_info("Couldn't init OTG timers\n");
+		goto err;
+	}
+	spin_lock_init(&fsl_otg_tc->fsm.lock);
+
+	/* Set OTG state machine operations */
+	fsl_otg_tc->fsm.ops = &fsl_otg_ops;
+
+	/* initialize the otg structure */
+	fsl_otg_tc->otg.label = DRIVER_DESC;
+	fsl_otg_tc->otg.set_host = fsl_otg_set_host;
+	fsl_otg_tc->otg.set_peripheral = fsl_otg_set_peripheral;
+	fsl_otg_tc->otg.set_power = fsl_otg_set_power;
+	fsl_otg_tc->otg.start_hnp = fsl_otg_start_hnp;
+	fsl_otg_tc->otg.start_srp = fsl_otg_start_srp;
+
+	fsl_otg_dev = fsl_otg_tc;
+
+	/* Store the otg transceiver */
+	status = otg_set_transceiver(&fsl_otg_tc->otg);
+	if (status) {
+		pr_warn(FSL_OTG_NAME ": unable to register OTG transceiver.\n");
+		goto err;
+	}
+
+	return 0;
+err:
+	fsl_otg_uninit_timers();
+	kfree(fsl_otg_tc);
+	return status;
+}
+
+/* OTG Initialization */
+int usb_otg_start(struct platform_device *pdev)
+{
+	struct fsl_otg *p_otg;
+	struct otg_transceiver *otg_trans = otg_get_transceiver();
+	struct otg_fsm *fsm;
+	int status;
+	struct resource *res;
+	u32 temp;
+	struct fsl_usb2_platform_data *pdata = pdev->dev.platform_data;
+
+	p_otg = container_of(otg_trans, struct fsl_otg, otg);
+	fsm = &p_otg->fsm;
+
+	/* Initialize the state machine structure with default values */
+	SET_OTG_STATE(otg_trans, OTG_STATE_UNDEFINED);
+	fsm->transceiver = &p_otg->otg;
+
+	/* We don't require predefined MEM/IRQ resource index */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENXIO;
+
+	/* We don't request_mem_region here to enable resource sharing
+	 * with host/device */
+
+	usb_dr_regs = ioremap(res->start, sizeof(struct usb_dr_mmap));
+	p_otg->dr_mem_map = (struct usb_dr_mmap *)usb_dr_regs;
+	pdata->regs = (void *)usb_dr_regs;
+
+	if (pdata->init && pdata->init(pdev) != 0)
+		return -EINVAL;
+
+	if (pdata->big_endian_mmio) {
+		_fsl_readl = _fsl_readl_be;
+		_fsl_writel = _fsl_writel_be;
+	} else {
+		_fsl_readl = _fsl_readl_le;
+		_fsl_writel = _fsl_writel_le;
+	}
+
+	/* request irq */
+	p_otg->irq = platform_get_irq(pdev, 0);
+	status = request_irq(p_otg->irq, fsl_otg_isr,
+				IRQF_SHARED, driver_name, p_otg);
+	if (status) {
+		dev_dbg(p_otg->otg.dev, "can't get IRQ %d, error %d\n",
+			p_otg->irq, status);
+		iounmap(p_otg->dr_mem_map);
+		kfree(p_otg);
+		return status;
+	}
+
+	/* stop the controller */
+	temp = fsl_readl(&p_otg->dr_mem_map->usbcmd);
+	temp &= ~USB_CMD_RUN_STOP;
+	fsl_writel(temp, &p_otg->dr_mem_map->usbcmd);
+
+	/* reset the controller */
+	temp = fsl_readl(&p_otg->dr_mem_map->usbcmd);
+	temp |= USB_CMD_CTRL_RESET;
+	fsl_writel(temp, &p_otg->dr_mem_map->usbcmd);
+
+	/* wait reset completed */
+	while (fsl_readl(&p_otg->dr_mem_map->usbcmd) & USB_CMD_CTRL_RESET)
+		;
+
+	/* configure the VBUSHS as IDLE(both host and device) */
+	temp = USB_MODE_STREAM_DISABLE | (pdata->es ? USB_MODE_ES : 0);
+	fsl_writel(temp, &p_otg->dr_mem_map->usbmode);
+
+	/* configure PHY interface */
+	temp = fsl_readl(&p_otg->dr_mem_map->portsc);
+	temp &= ~(PORTSC_PHY_TYPE_SEL | PORTSC_PTW);
+	switch (pdata->phy_mode) {
+	case FSL_USB2_PHY_ULPI:
+		temp |= PORTSC_PTS_ULPI;
+		break;
+	case FSL_USB2_PHY_UTMI_WIDE:
+		temp |= PORTSC_PTW_16BIT;
+		/* fall through */
+	case FSL_USB2_PHY_UTMI:
+		temp |= PORTSC_PTS_UTMI;
+		/* fall through */
+	default:
+		break;
+	}
+	fsl_writel(temp, &p_otg->dr_mem_map->portsc);
+
+	if (pdata->have_sysif_regs) {
+		/* configure control enable IO output, big endian register */
+		temp = __raw_readl(&p_otg->dr_mem_map->control);
+		temp |= USB_CTRL_IOENB;
+		__raw_writel(temp, &p_otg->dr_mem_map->control);
+	}
+
+	/* disable all interrupt and clear all OTGSC status */
+	temp = fsl_readl(&p_otg->dr_mem_map->otgsc);
+	temp &= ~OTGSC_INTERRUPT_ENABLE_BITS_MASK;
+	temp |= OTGSC_INTERRUPT_STATUS_BITS_MASK | OTGSC_CTRL_VBUS_DISCHARGE;
+	fsl_writel(temp, &p_otg->dr_mem_map->otgsc);
+
+	/*
+	 * The identification (id) input is FALSE when a Mini-A plug is inserted
+	 * in the devices Mini-AB receptacle. Otherwise, this input is TRUE.
+	 * Also: record initial state of ID pin
+	 */
+	if (fsl_readl(&p_otg->dr_mem_map->otgsc) & OTGSC_STS_USB_ID) {
+		p_otg->otg.state = OTG_STATE_UNDEFINED;
+		p_otg->fsm.id = 1;
+	} else {
+		p_otg->otg.state = OTG_STATE_A_IDLE;
+		p_otg->fsm.id = 0;
+	}
+
+	DBG("initial ID pin=%d\n", p_otg->fsm.id);
+
+	/* enable OTG ID pin interrupt */
+	temp = fsl_readl(&p_otg->dr_mem_map->otgsc);
+	temp |= OTGSC_INTR_USB_ID_EN;
+	temp &= ~(OTGSC_CTRL_VBUS_DISCHARGE | OTGSC_INTR_1MS_TIMER_EN);
+	fsl_writel(temp, &p_otg->dr_mem_map->otgsc);
+
+	return 0;
+}
+
+/*
+ * state file in sysfs
+ */
+static int show_fsl_usb2_otg_state(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct otg_fsm *fsm = &fsl_otg_dev->fsm;
+	char *next = buf;
+	unsigned size = PAGE_SIZE;
+	unsigned long flags;
+	int t;
+
+	spin_lock_irqsave(&fsm->lock, flags);
+
+	/* basic driver infomation */
+	t = scnprintf(next, size,
+			DRIVER_DESC "\n" "fsl_usb2_otg version: %s\n\n",
+			DRIVER_VERSION);
+	size -= t;
+	next += t;
+
+	/* Registers */
+	t = scnprintf(next, size,
+			"OTGSC:   0x%08x\n"
+			"PORTSC:  0x%08x\n"
+			"USBMODE: 0x%08x\n"
+			"USBCMD:  0x%08x\n"
+			"USBSTS:  0x%08x\n"
+			"USBINTR: 0x%08x\n",
+			fsl_readl(&usb_dr_regs->otgsc),
+			fsl_readl(&usb_dr_regs->portsc),
+			fsl_readl(&usb_dr_regs->usbmode),
+			fsl_readl(&usb_dr_regs->usbcmd),
+			fsl_readl(&usb_dr_regs->usbsts),
+			fsl_readl(&usb_dr_regs->usbintr));
+	size -= t;
+	next += t;
+
+	/* State */
+	t = scnprintf(next, size,
+		      "OTG state: %s\n\n",
+		      otg_state_string(fsl_otg_dev->otg.state));
+	size -= t;
+	next += t;
+
+	/* State Machine Variables */
+	t = scnprintf(next, size,
+			"a_bus_req: %d\n"
+			"b_bus_req: %d\n"
+			"a_bus_resume: %d\n"
+			"a_bus_suspend: %d\n"
+			"a_conn: %d\n"
+			"a_sess_vld: %d\n"
+			"a_srp_det: %d\n"
+			"a_vbus_vld: %d\n"
+			"b_bus_resume: %d\n"
+			"b_bus_suspend: %d\n"
+			"b_conn: %d\n"
+			"b_se0_srp: %d\n"
+			"b_sess_end: %d\n"
+			"b_sess_vld: %d\n"
+			"id: %d\n",
+			fsm->a_bus_req,
+			fsm->b_bus_req,
+			fsm->a_bus_resume,
+			fsm->a_bus_suspend,
+			fsm->a_conn,
+			fsm->a_sess_vld,
+			fsm->a_srp_det,
+			fsm->a_vbus_vld,
+			fsm->b_bus_resume,
+			fsm->b_bus_suspend,
+			fsm->b_conn,
+			fsm->b_se0_srp,
+			fsm->b_sess_end,
+			fsm->b_sess_vld,
+			fsm->id);
+	size -= t;
+	next += t;
+
+	spin_unlock_irqrestore(&fsm->lock, flags);
+
+	return PAGE_SIZE - size;
+}
+
+static DEVICE_ATTR(fsl_usb2_otg_state, S_IRUGO, show_fsl_usb2_otg_state, NULL);
+
+
+/* Char driver interface to control some OTG input */
+
+/*
+ * Handle some ioctl command, such as get otg
+ * status and set host suspend
+ */
+static long fsl_otg_ioctl(struct file *file, unsigned int cmd,
+			  unsigned long arg)
+{
+	u32 retval = 0;
+
+	switch (cmd) {
+	case GET_OTG_STATUS:
+		retval = fsl_otg_dev->host_working;
+		break;
+
+	case SET_A_SUSPEND_REQ:
+		fsl_otg_dev->fsm.a_suspend_req = arg;
+		break;
+
+	case SET_A_BUS_DROP:
+		fsl_otg_dev->fsm.a_bus_drop = arg;
+		break;
+
+	case SET_A_BUS_REQ:
+		fsl_otg_dev->fsm.a_bus_req = arg;
+		break;
+
+	case SET_B_BUS_REQ:
+		fsl_otg_dev->fsm.b_bus_req = arg;
+		break;
+
+	default:
+		break;
+	}
+
+	otg_statemachine(&fsl_otg_dev->fsm);
+
+	return retval;
+}
+
+static int fsl_otg_open(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+static int fsl_otg_release(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+static const struct file_operations otg_fops = {
+	.owner = THIS_MODULE,
+	.llseek = NULL,
+	.read = NULL,
+	.write = NULL,
+	.unlocked_ioctl = fsl_otg_ioctl,
+	.open = fsl_otg_open,
+	.release = fsl_otg_release,
+};
+
+static int __devinit fsl_otg_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	if (!pdev->dev.platform_data)
+		return -ENODEV;
+
+	/* configure the OTG */
+	ret = fsl_otg_conf(pdev);
+	if (ret) {
+		dev_err(&pdev->dev, "Couldn't configure OTG module\n");
+		return ret;
+	}
+
+	/* start OTG */
+	ret = usb_otg_start(pdev);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't init FSL OTG device\n");
+		return ret;
+	}
+
+	ret = register_chrdev(FSL_OTG_MAJOR, FSL_OTG_NAME, &otg_fops);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to register FSL OTG device\n");
+		return ret;
+	}
+
+	ret = device_create_file(&pdev->dev, &dev_attr_fsl_usb2_otg_state);
+	if (ret)
+		dev_warn(&pdev->dev, "Can't register sysfs attribute\n");
+
+	return ret;
+}
+
+static int __devexit fsl_otg_remove(struct platform_device *pdev)
+{
+	struct fsl_usb2_platform_data *pdata = pdev->dev.platform_data;
+
+	otg_set_transceiver(NULL);
+	free_irq(fsl_otg_dev->irq, fsl_otg_dev);
+
+	iounmap((void *)usb_dr_regs);
+
+	fsl_otg_uninit_timers();
+	kfree(fsl_otg_dev);
+
+	device_remove_file(&pdev->dev, &dev_attr_fsl_usb2_otg_state);
+
+	unregister_chrdev(FSL_OTG_MAJOR, FSL_OTG_NAME);
+
+	if (pdata->exit)
+		pdata->exit(pdev);
+
+	return 0;
+}
+
+struct platform_driver fsl_otg_driver = {
+	.probe = fsl_otg_probe,
+	.remove = __devexit_p(fsl_otg_remove),
+	.driver = {
+		.name = driver_name,
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init fsl_usb_otg_init(void)
+{
+	pr_info(DRIVER_INFO "\n");
+	return platform_driver_register(&fsl_otg_driver);
+}
+module_init(fsl_usb_otg_init);
+
+static void __exit fsl_usb_otg_exit(void)
+{
+	platform_driver_unregister(&fsl_otg_driver);
+}
+module_exit(fsl_usb_otg_exit);
+
+MODULE_DESCRIPTION(DRIVER_INFO);
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_LICENSE("GPL");