Initial import

1 files changed, 816 insertions, 0 deletions

diff --git a/drivers/usb/chipidea/otg_fsm.c b/drivers/usb/chipidea/otg_fsm.c
new file mode 100644
index 000000000..19d655a74
--- /dev/null
+++ b/drivers/usb/chipidea/otg_fsm.c
@@ -0,0 +1,816 @@
+/*
+ * otg_fsm.c - ChipIdea USB IP core OTG FSM driver
+ *
+ * Copyright (C) 2014 Freescale Semiconductor, Inc.
+ *
+ * Author: Jun Li
+ *
+ * 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 OTG fsm, it includes OTG fsm operations
+ * for HNP and SRP.
+ *
+ * TODO List
+ * - ADP
+ * - OTG test device
+ */
+
+#include <linux/usb/otg.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/hcd.h>
+#include <linux/usb/chipidea.h>
+#include <linux/regulator/consumer.h>
+
+#include "ci.h"
+#include "bits.h"
+#include "otg.h"
+#include "otg_fsm.h"
+
+/* Add for otg: interact with user space app */
+static ssize_t
+get_a_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	char		*next;
+	unsigned	size, t;
+	struct ci_hdrc	*ci = dev_get_drvdata(dev);
+
+	next = buf;
+	size = PAGE_SIZE;
+	t = scnprintf(next, size, "%d\n", ci->fsm.a_bus_req);
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+
+static ssize_t
+set_a_bus_req(struct device *dev, struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct ci_hdrc *ci = dev_get_drvdata(dev);
+
+	if (count > 2)
+		return -1;
+
+	mutex_lock(&ci->fsm.lock);
+	if (buf[0] == '0') {
+		ci->fsm.a_bus_req = 0;
+	} else if (buf[0] == '1') {
+		/* If a_bus_drop is TRUE, a_bus_req can't be set */
+		if (ci->fsm.a_bus_drop) {
+			mutex_unlock(&ci->fsm.lock);
+			return count;
+		}
+		ci->fsm.a_bus_req = 1;
+	}
+
+	ci_otg_queue_work(ci);
+	mutex_unlock(&ci->fsm.lock);
+
+	return count;
+}
+static DEVICE_ATTR(a_bus_req, S_IRUGO | S_IWUSR, get_a_bus_req, set_a_bus_req);
+
+static ssize_t
+get_a_bus_drop(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	char		*next;
+	unsigned	size, t;
+	struct ci_hdrc	*ci = dev_get_drvdata(dev);
+
+	next = buf;
+	size = PAGE_SIZE;
+	t = scnprintf(next, size, "%d\n", ci->fsm.a_bus_drop);
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+
+static ssize_t
+set_a_bus_drop(struct device *dev, struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct ci_hdrc	*ci = dev_get_drvdata(dev);
+
+	if (count > 2)
+		return -1;
+
+	mutex_lock(&ci->fsm.lock);
+	if (buf[0] == '0') {
+		ci->fsm.a_bus_drop = 0;
+	} else if (buf[0] == '1') {
+		ci->fsm.a_bus_drop = 1;
+		ci->fsm.a_bus_req = 0;
+	}
+
+	ci_otg_queue_work(ci);
+	mutex_unlock(&ci->fsm.lock);
+
+	return count;
+}
+static DEVICE_ATTR(a_bus_drop, S_IRUGO | S_IWUSR, get_a_bus_drop,
+						set_a_bus_drop);
+
+static ssize_t
+get_b_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	char		*next;
+	unsigned	size, t;
+	struct ci_hdrc	*ci = dev_get_drvdata(dev);
+
+	next = buf;
+	size = PAGE_SIZE;
+	t = scnprintf(next, size, "%d\n", ci->fsm.b_bus_req);
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+
+static ssize_t
+set_b_bus_req(struct device *dev, struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct ci_hdrc	*ci = dev_get_drvdata(dev);
+
+	if (count > 2)
+		return -1;
+
+	mutex_lock(&ci->fsm.lock);
+	if (buf[0] == '0')
+		ci->fsm.b_bus_req = 0;
+	else if (buf[0] == '1')
+		ci->fsm.b_bus_req = 1;
+
+	ci_otg_queue_work(ci);
+	mutex_unlock(&ci->fsm.lock);
+
+	return count;
+}
+static DEVICE_ATTR(b_bus_req, S_IRUGO | S_IWUSR, get_b_bus_req, set_b_bus_req);
+
+static ssize_t
+set_a_clr_err(struct device *dev, struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct ci_hdrc	*ci = dev_get_drvdata(dev);
+
+	if (count > 2)
+		return -1;
+
+	mutex_lock(&ci->fsm.lock);
+	if (buf[0] == '1')
+		ci->fsm.a_clr_err = 1;
+
+	ci_otg_queue_work(ci);
+	mutex_unlock(&ci->fsm.lock);
+
+	return count;
+}
+static DEVICE_ATTR(a_clr_err, S_IWUSR, NULL, set_a_clr_err);
+
+static struct attribute *inputs_attrs[] = {
+	&dev_attr_a_bus_req.attr,
+	&dev_attr_a_bus_drop.attr,
+	&dev_attr_b_bus_req.attr,
+	&dev_attr_a_clr_err.attr,
+	NULL,
+};
+
+static struct attribute_group inputs_attr_group = {
+	.name = "inputs",
+	.attrs = inputs_attrs,
+};
+
+/*
+ * Keep this list in the same order as timers indexed
+ * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
+ */
+static unsigned otg_timer_ms[] = {
+	TA_WAIT_VRISE,
+	TA_WAIT_VFALL,
+	TA_WAIT_BCON,
+	TA_AIDL_BDIS,
+	TB_ASE0_BRST,
+	TA_BIDL_ADIS,
+	TB_SE0_SRP,
+	TB_SRP_FAIL,
+	0,
+	TB_DATA_PLS,
+	TB_SSEND_SRP,
+};
+
+/*
+ * Add timer to active timer list
+ */
+static void ci_otg_add_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
+{
+	unsigned long flags, timer_sec, timer_nsec;
+
+	if (t >= NUM_OTG_FSM_TIMERS)
+		return;
+
+	spin_lock_irqsave(&ci->lock, flags);
+	timer_sec = otg_timer_ms[t] / MSEC_PER_SEC;
+	timer_nsec = (otg_timer_ms[t] % MSEC_PER_SEC) * NSEC_PER_MSEC;
+	ci->hr_timeouts[t] = ktime_add(ktime_get(),
+				ktime_set(timer_sec, timer_nsec));
+	ci->enabled_otg_timer_bits |= (1 << t);
+	if ((ci->next_otg_timer == NUM_OTG_FSM_TIMERS) ||
+			(ci->hr_timeouts[ci->next_otg_timer].tv64 >
+						ci->hr_timeouts[t].tv64)) {
+			ci->next_otg_timer = t;
+			hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
+					ci->hr_timeouts[t], NSEC_PER_MSEC,
+							HRTIMER_MODE_ABS);
+	}
+	spin_unlock_irqrestore(&ci->lock, flags);
+}
+
+/*
+ * Remove timer from active timer list
+ */
+static void ci_otg_del_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
+{
+	unsigned long flags, enabled_timer_bits;
+	enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
+
+	if ((t >= NUM_OTG_FSM_TIMERS) ||
+			!(ci->enabled_otg_timer_bits & (1 << t)))
+		return;
+
+	spin_lock_irqsave(&ci->lock, flags);
+	ci->enabled_otg_timer_bits &= ~(1 << t);
+	if (ci->next_otg_timer == t) {
+		if (ci->enabled_otg_timer_bits == 0) {
+			/* No enabled timers after delete it */
+			hrtimer_cancel(&ci->otg_fsm_hrtimer);
+			ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
+		} else {
+			/* Find the next timer */
+			enabled_timer_bits = ci->enabled_otg_timer_bits;
+			for_each_set_bit(cur_timer, &enabled_timer_bits,
+							NUM_OTG_FSM_TIMERS) {
+				if ((next_timer == NUM_OTG_FSM_TIMERS) ||
+					(ci->hr_timeouts[next_timer].tv64 <
+					ci->hr_timeouts[cur_timer].tv64))
+					next_timer = cur_timer;
+			}
+		}
+	}
+	if (next_timer != NUM_OTG_FSM_TIMERS) {
+		ci->next_otg_timer = next_timer;
+		hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
+			ci->hr_timeouts[next_timer], NSEC_PER_MSEC,
+							HRTIMER_MODE_ABS);
+	}
+	spin_unlock_irqrestore(&ci->lock, flags);
+}
+
+/* OTG FSM timer handlers */
+static int a_wait_vrise_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.a_wait_vrise_tmout = 1;
+	return 0;
+}
+
+static int a_wait_vfall_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.a_wait_vfall_tmout = 1;
+	return 0;
+}
+
+static int a_wait_bcon_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.a_wait_bcon_tmout = 1;
+	return 0;
+}
+
+static int a_aidl_bdis_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.a_aidl_bdis_tmout = 1;
+	return 0;
+}
+
+static int b_ase0_brst_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.b_ase0_brst_tmout = 1;
+	return 0;
+}
+
+static int a_bidl_adis_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.a_bidl_adis_tmout = 1;
+	return 0;
+}
+
+static int b_se0_srp_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.b_se0_srp = 1;
+	return 0;
+}
+
+static int b_srp_fail_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.b_srp_done = 1;
+	return 1;
+}
+
+static int b_data_pls_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.b_srp_done = 1;
+	ci->fsm.b_bus_req = 0;
+	if (ci->fsm.power_up)
+		ci->fsm.power_up = 0;
+	hw_write_otgsc(ci, OTGSC_HABA, 0);
+	pm_runtime_put(ci->dev);
+	return 0;
+}
+
+static int b_ssend_srp_tmout(struct ci_hdrc *ci)
+{
+	ci->fsm.b_ssend_srp = 1;
+	/* only vbus fall below B_sess_vld in b_idle state */
+	if (ci->fsm.otg->state == OTG_STATE_B_IDLE)
+		return 0;
+	else
+		return 1;
+}
+
+/*
+ * Keep this list in the same order as timers indexed
+ * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
+ */
+static int (*otg_timer_handlers[])(struct ci_hdrc *) = {
+	a_wait_vrise_tmout,	/* A_WAIT_VRISE */
+	a_wait_vfall_tmout,	/* A_WAIT_VFALL */
+	a_wait_bcon_tmout,	/* A_WAIT_BCON */
+	a_aidl_bdis_tmout,	/* A_AIDL_BDIS */
+	b_ase0_brst_tmout,	/* B_ASE0_BRST */
+	a_bidl_adis_tmout,	/* A_BIDL_ADIS */
+	b_se0_srp_tmout,	/* B_SE0_SRP */
+	b_srp_fail_tmout,	/* B_SRP_FAIL */
+	NULL,			/* A_WAIT_ENUM */
+	b_data_pls_tmout,	/* B_DATA_PLS */
+	b_ssend_srp_tmout,	/* B_SSEND_SRP */
+};
+
+/*
+ * Enable the next nearest enabled timer if have
+ */
+static enum hrtimer_restart ci_otg_hrtimer_func(struct hrtimer *t)
+{
+	struct ci_hdrc *ci = container_of(t, struct ci_hdrc, otg_fsm_hrtimer);
+	ktime_t	now, *timeout;
+	unsigned long   enabled_timer_bits;
+	unsigned long   flags;
+	enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
+	int ret = -EINVAL;
+
+	spin_lock_irqsave(&ci->lock, flags);
+	enabled_timer_bits = ci->enabled_otg_timer_bits;
+	ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
+
+	now = ktime_get();
+	for_each_set_bit(cur_timer, &enabled_timer_bits, NUM_OTG_FSM_TIMERS) {
+		if (now.tv64 >= ci->hr_timeouts[cur_timer].tv64) {
+			ci->enabled_otg_timer_bits &= ~(1 << cur_timer);
+			if (otg_timer_handlers[cur_timer])
+				ret = otg_timer_handlers[cur_timer](ci);
+		} else {
+			if ((next_timer == NUM_OTG_FSM_TIMERS) ||
+				(ci->hr_timeouts[cur_timer].tv64 <
+					ci->hr_timeouts[next_timer].tv64))
+				next_timer = cur_timer;
+		}
+	}
+	/* Enable the next nearest timer */
+	if (next_timer < NUM_OTG_FSM_TIMERS) {
+		timeout = &ci->hr_timeouts[next_timer];
+		hrtimer_start_range_ns(&ci->otg_fsm_hrtimer, *timeout,
+					NSEC_PER_MSEC, HRTIMER_MODE_ABS);
+		ci->next_otg_timer = next_timer;
+	}
+	spin_unlock_irqrestore(&ci->lock, flags);
+
+	if (!ret)
+		ci_otg_queue_work(ci);
+
+	return HRTIMER_NORESTART;
+}
+
+/* Initialize timers */
+static int ci_otg_init_timers(struct ci_hdrc *ci)
+{
+	hrtimer_init(&ci->otg_fsm_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+	ci->otg_fsm_hrtimer.function = ci_otg_hrtimer_func;
+
+	return 0;
+}
+
+/* -------------------------------------------------------------*/
+/* Operations that will be called from OTG Finite State Machine */
+/* -------------------------------------------------------------*/
+static void ci_otg_fsm_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
+{
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	if (t < NUM_OTG_FSM_TIMERS)
+		ci_otg_add_timer(ci, t);
+	return;
+}
+
+static void ci_otg_fsm_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
+{
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	if (t < NUM_OTG_FSM_TIMERS)
+		ci_otg_del_timer(ci, t);
+	return;
+}
+
+/*
+ * A-device drive vbus: turn on vbus regulator and enable port power
+ * Data pulse irq should be disabled while vbus is on.
+ */
+static void ci_otg_drv_vbus(struct otg_fsm *fsm, int on)
+{
+	int ret;
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	if (on) {
+		/* Enable power power */
+		hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS | PORTSC_PP,
+							PORTSC_PP);
+		if (ci->platdata->reg_vbus) {
+			ret = regulator_enable(ci->platdata->reg_vbus);
+			if (ret) {
+				dev_err(ci->dev,
+				"Failed to enable vbus regulator, ret=%d\n",
+				ret);
+				return;
+			}
+		}
+		/* Disable data pulse irq */
+		hw_write_otgsc(ci, OTGSC_DPIE, 0);
+
+		fsm->a_srp_det = 0;
+		fsm->power_up = 0;
+	} else {
+		if (ci->platdata->reg_vbus)
+			regulator_disable(ci->platdata->reg_vbus);
+
+		fsm->a_bus_drop = 1;
+		fsm->a_bus_req = 0;
+	}
+}
+
+/*
+ * Control data line by Run Stop bit.
+ */
+static void ci_otg_loc_conn(struct otg_fsm *fsm, int on)
+{
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	if (on)
+		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
+	else
+		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
+}
+
+/*
+ * 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.
+ */
+static void ci_otg_loc_sof(struct otg_fsm *fsm, int on)
+{
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	if (on)
+		hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS | PORTSC_FPR,
+							PORTSC_FPR);
+	else
+		hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS | PORTSC_SUSP,
+							PORTSC_SUSP);
+}
+
+/*
+ * Start SRP pulsing by data-line pulsing,
+ * no v-bus pulsing followed
+ */
+static void ci_otg_start_pulse(struct otg_fsm *fsm)
+{
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	/* Hardware Assistant Data pulse */
+	hw_write_otgsc(ci, OTGSC_HADP, OTGSC_HADP);
+
+	pm_runtime_get(ci->dev);
+	ci_otg_add_timer(ci, B_DATA_PLS);
+}
+
+static int ci_otg_start_host(struct otg_fsm *fsm, int on)
+{
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	if (on) {
+		ci_role_stop(ci);
+		ci_role_start(ci, CI_ROLE_HOST);
+	} else {
+		ci_role_stop(ci);
+		hw_device_reset(ci);
+		ci_role_start(ci, CI_ROLE_GADGET);
+	}
+	return 0;
+}
+
+static int ci_otg_start_gadget(struct otg_fsm *fsm, int on)
+{
+	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
+
+	if (on)
+		usb_gadget_vbus_connect(&ci->gadget);
+	else
+		usb_gadget_vbus_disconnect(&ci->gadget);
+
+	return 0;
+}
+
+static struct otg_fsm_ops ci_otg_ops = {
+	.drv_vbus = ci_otg_drv_vbus,
+	.loc_conn = ci_otg_loc_conn,
+	.loc_sof = ci_otg_loc_sof,
+	.start_pulse = ci_otg_start_pulse,
+	.add_timer = ci_otg_fsm_add_timer,
+	.del_timer = ci_otg_fsm_del_timer,
+	.start_host = ci_otg_start_host,
+	.start_gadget = ci_otg_start_gadget,
+};
+
+int ci_otg_fsm_work(struct ci_hdrc *ci)
+{
+	/*
+	 * Don't do fsm transition for B device
+	 * when there is no gadget class driver
+	 */
+	if (ci->fsm.id && !(ci->driver) &&
+		ci->fsm.otg->state < OTG_STATE_A_IDLE)
+		return 0;
+
+	pm_runtime_get_sync(ci->dev);
+	if (otg_statemachine(&ci->fsm)) {
+		if (ci->fsm.otg->state == OTG_STATE_A_IDLE) {
+			/*
+			 * Further state change for cases:
+			 * a_idle to b_idle; or
+			 * a_idle to a_wait_vrise due to ID change(1->0), so
+			 * B-dev becomes A-dev can try to start new session
+			 * consequently; or
+			 * a_idle to a_wait_vrise when power up
+			 */
+			if ((ci->fsm.id) || (ci->id_event) ||
+						(ci->fsm.power_up)) {
+				ci_otg_queue_work(ci);
+			} else {
+				/* Enable data pulse irq */
+				hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS |
+								PORTSC_PP, 0);
+				hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
+				hw_write_otgsc(ci, OTGSC_DPIE, OTGSC_DPIE);
+			}
+			if (ci->id_event)
+				ci->id_event = false;
+		} else if (ci->fsm.otg->state == OTG_STATE_B_IDLE) {
+			if (ci->fsm.b_sess_vld) {
+				ci->fsm.power_up = 0;
+				/*
+				 * Further transite to b_periphearl state
+				 * when register gadget driver with vbus on
+				 */
+				ci_otg_queue_work(ci);
+			}
+		} else if (ci->fsm.otg->state == OTG_STATE_A_HOST) {
+			pm_runtime_mark_last_busy(ci->dev);
+			pm_runtime_put_autosuspend(ci->dev);
+			return 0;
+		}
+	}
+	pm_runtime_put_sync(ci->dev);
+	return 0;
+}
+
+/*
+ * Update fsm variables in each state if catching expected interrupts,
+ * called by otg fsm isr.
+ */
+static void ci_otg_fsm_event(struct ci_hdrc *ci)
+{
+	u32 intr_sts, otg_bsess_vld, port_conn;
+	struct otg_fsm *fsm = &ci->fsm;
+
+	intr_sts = hw_read_intr_status(ci);
+	otg_bsess_vld = hw_read_otgsc(ci, OTGSC_BSV);
+	port_conn = hw_read(ci, OP_PORTSC, PORTSC_CCS);
+
+	switch (ci->fsm.otg->state) {
+	case OTG_STATE_A_WAIT_BCON:
+		if (port_conn) {
+			fsm->b_conn = 1;
+			fsm->a_bus_req = 1;
+			ci_otg_queue_work(ci);
+		}
+		break;
+	case OTG_STATE_B_IDLE:
+		if (otg_bsess_vld && (intr_sts & USBi_PCI) && port_conn) {
+			fsm->b_sess_vld = 1;
+			ci_otg_queue_work(ci);
+		}
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		if ((intr_sts & USBi_SLI) && port_conn && otg_bsess_vld) {
+			fsm->a_bus_suspend = 1;
+			ci_otg_queue_work(ci);
+		} else if (intr_sts & USBi_PCI) {
+			if (fsm->a_bus_suspend == 1)
+				fsm->a_bus_suspend = 0;
+		}
+		break;
+	case OTG_STATE_B_HOST:
+		if ((intr_sts & USBi_PCI) && !port_conn) {
+			fsm->a_conn = 0;
+			fsm->b_bus_req = 0;
+			ci_otg_queue_work(ci);
+		}
+		break;
+	case OTG_STATE_A_PERIPHERAL:
+		if (intr_sts & USBi_SLI) {
+			 fsm->b_bus_suspend = 1;
+			/*
+			 * Init a timer to know how long this suspend
+			 * will continue, if time out, indicates B no longer
+			 * wants to be host role
+			 */
+			 ci_otg_add_timer(ci, A_BIDL_ADIS);
+		}
+
+		if (intr_sts & USBi_URI)
+			ci_otg_del_timer(ci, A_BIDL_ADIS);
+
+		if (intr_sts & USBi_PCI) {
+			if (fsm->b_bus_suspend == 1) {
+				ci_otg_del_timer(ci, A_BIDL_ADIS);
+				fsm->b_bus_suspend = 0;
+			}
+		}
+		break;
+	case OTG_STATE_A_SUSPEND:
+		if ((intr_sts & USBi_PCI) && !port_conn) {
+			fsm->b_conn = 0;
+
+			/* if gadget driver is binded */
+			if (ci->driver) {
+				/* A device to be peripheral mode */
+				ci->gadget.is_a_peripheral = 1;
+			}
+			ci_otg_queue_work(ci);
+		}
+		break;
+	case OTG_STATE_A_HOST:
+		if ((intr_sts & USBi_PCI) && !port_conn) {
+			fsm->b_conn = 0;
+			ci_otg_queue_work(ci);
+		}
+		break;
+	case OTG_STATE_B_WAIT_ACON:
+		if ((intr_sts & USBi_PCI) && port_conn) {
+			fsm->a_conn = 1;
+			ci_otg_queue_work(ci);
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+/*
+ * ci_otg_irq - otg fsm related irq handling
+ * and also update otg fsm variable by monitoring usb host and udc
+ * state change interrupts.
+ * @ci: ci_hdrc
+ */
+irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci)
+{
+	irqreturn_t retval =  IRQ_NONE;
+	u32 otgsc, otg_int_src = 0;
+	struct otg_fsm *fsm = &ci->fsm;
+
+	otgsc = hw_read_otgsc(ci, ~0);
+	otg_int_src = otgsc & OTGSC_INT_STATUS_BITS & (otgsc >> 8);
+	fsm->id = (otgsc & OTGSC_ID) ? 1 : 0;
+
+	if (otg_int_src) {
+		if (otg_int_src & OTGSC_DPIS) {
+			hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
+			fsm->a_srp_det = 1;
+			fsm->a_bus_drop = 0;
+		} else if (otg_int_src & OTGSC_IDIS) {
+			hw_write_otgsc(ci, OTGSC_IDIS, OTGSC_IDIS);
+			if (fsm->id == 0) {
+				fsm->a_bus_drop = 0;
+				fsm->a_bus_req = 1;
+				ci->id_event = true;
+			}
+		} else if (otg_int_src & OTGSC_BSVIS) {
+			hw_write_otgsc(ci, OTGSC_BSVIS, OTGSC_BSVIS);
+			if (otgsc & OTGSC_BSV) {
+				fsm->b_sess_vld = 1;
+				ci_otg_del_timer(ci, B_SSEND_SRP);
+				ci_otg_del_timer(ci, B_SRP_FAIL);
+				fsm->b_ssend_srp = 0;
+			} else {
+				fsm->b_sess_vld = 0;
+				if (fsm->id)
+					ci_otg_add_timer(ci, B_SSEND_SRP);
+			}
+		} else if (otg_int_src & OTGSC_AVVIS) {
+			hw_write_otgsc(ci, OTGSC_AVVIS, OTGSC_AVVIS);
+			if (otgsc & OTGSC_AVV) {
+				fsm->a_vbus_vld = 1;
+			} else {
+				fsm->a_vbus_vld = 0;
+				fsm->b_conn = 0;
+			}
+		}
+		ci_otg_queue_work(ci);
+		return IRQ_HANDLED;
+	}
+
+	ci_otg_fsm_event(ci);
+
+	return retval;
+}
+
+void ci_hdrc_otg_fsm_start(struct ci_hdrc *ci)
+{
+	ci_otg_queue_work(ci);
+}
+
+int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
+{
+	int retval = 0;
+
+	if (ci->phy)
+		ci->otg.phy = ci->phy;
+	else
+		ci->otg.usb_phy = ci->usb_phy;
+
+	ci->otg.gadget = &ci->gadget;
+	ci->fsm.otg = &ci->otg;
+	ci->fsm.power_up = 1;
+	ci->fsm.id = hw_read_otgsc(ci, OTGSC_ID) ? 1 : 0;
+	ci->fsm.otg->state = OTG_STATE_UNDEFINED;
+	ci->fsm.ops = &ci_otg_ops;
+
+	mutex_init(&ci->fsm.lock);
+
+	retval = ci_otg_init_timers(ci);
+	if (retval) {
+		dev_err(ci->dev, "Couldn't init OTG timers\n");
+		return retval;
+	}
+	ci->enabled_otg_timer_bits = 0;
+	ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
+
+	retval = sysfs_create_group(&ci->dev->kobj, &inputs_attr_group);
+	if (retval < 0) {
+		dev_dbg(ci->dev,
+			"Can't register sysfs attr group: %d\n", retval);
+		return retval;
+	}
+
+	/* Enable A vbus valid irq */
+	hw_write_otgsc(ci, OTGSC_AVVIE, OTGSC_AVVIE);
+
+	if (ci->fsm.id) {
+		ci->fsm.b_ssend_srp =
+			hw_read_otgsc(ci, OTGSC_BSV) ? 0 : 1;
+		ci->fsm.b_sess_vld =
+			hw_read_otgsc(ci, OTGSC_BSV) ? 1 : 0;
+		/* Enable BSV irq */
+		hw_write_otgsc(ci, OTGSC_BSVIE, OTGSC_BSVIE);
+	}
+
+	return 0;
+}
+
+void ci_hdrc_otg_fsm_remove(struct ci_hdrc *ci)
+{
+	sysfs_remove_group(&ci->dev->kobj, &inputs_attr_group);
+}