path: root/drivers/usb/pd/pd_engine.c

/*
 * Copyright 2016-2017 Google, Inc
 *
 * 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.
 */

#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/extcon.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/power_supply.h>
#include <linux/property.h>
#include <linux/regulator/consumer.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/usb/typec.h>
#include <linux/workqueue.h>

#include "../typec/pd.h"
#include "../typec/tcpm.h"
#include "usbpd.h"

#define LOG_BUFFER_ENTRIES	1024
#define LOG_BUFFER_ENTRY_SIZE	256

struct usbpd {
	struct device		dev;

	struct tcpm_port	*tcpm_port;
	struct tcpc_dev		tcpc_dev;

	struct pd_phy_params	pdphy_params;
	bool			pdphy_open;

	struct extcon_dev	*extcon;

	struct power_supply	*usb_psy;
	struct notifier_block	psy_nb;

	struct regulator	*vbus;
	struct regulator	*vconn;
	bool			vbus_output;
	bool			vconn_output;

	bool			vbus_present;
	enum power_supply_type	psy_type;
	enum typec_cc_status	cc1;
	enum typec_cc_status	cc2;
	bool			is_cable_flipped;

	bool			pending_update_usb_data;
	bool			extcon_usb;
	bool			extcon_usb_host;
	bool			extcon_usb_cc;
	bool			extcon_usb_ss;

	struct mutex		lock; /* struct usbpd access lock */
	struct workqueue_struct	*wq;

	/* debugfs logging */
	struct dentry *dentry;
	struct mutex logbuffer_lock;	/* log buffer access lock */
	int logbuffer_head;
	int logbuffer_tail;
	u8 *logbuffer[LOG_BUFFER_ENTRIES];
	bool in_pr_swap;
	bool suspend_supported;
};

/*
 * Logging
 */
static bool pd_engine_log_full(struct usbpd *pd)
{
	return pd->logbuffer_tail ==
		(pd->logbuffer_head + 1) % LOG_BUFFER_ENTRIES;
}

static void _pd_engine_log(struct usbpd *pd, const char *fmt, va_list args)
{
	char tmpbuffer[LOG_BUFFER_ENTRY_SIZE];
	u64 ts_nsec = local_clock();
	unsigned long rem_nsec;

	if (!pd->logbuffer[pd->logbuffer_head]) {
		pd->logbuffer[pd->logbuffer_head] =
			kzalloc(LOG_BUFFER_ENTRY_SIZE, GFP_KERNEL);
		if (!pd->logbuffer[pd->logbuffer_head])
			return;
	}

	vsnprintf(tmpbuffer, sizeof(tmpbuffer), fmt, args);

	mutex_lock(&pd->logbuffer_lock);

	if (pd_engine_log_full(pd)) {
		pd->logbuffer_head = max(pd->logbuffer_head - 1, 0);
		strlcpy(tmpbuffer, "overflow", LOG_BUFFER_ENTRY_SIZE);
	}

	if (pd->logbuffer_head < 0 ||
	    pd->logbuffer_head >= LOG_BUFFER_ENTRIES) {
		dev_warn(&pd->dev,
			 "Bad log buffer index %d\n", pd->logbuffer_head);
		goto abort;
	}

	if (!pd->logbuffer[pd->logbuffer_head]) {
		dev_warn(&pd->dev,
			 "Log buffer index %d is NULL\n", pd->logbuffer_head);
		goto abort;
	}

	rem_nsec = do_div(ts_nsec, 1000000000);
	scnprintf(pd->logbuffer[pd->logbuffer_head],
		  LOG_BUFFER_ENTRY_SIZE, "[%5lu.%06lu] %s",
		  (unsigned long)ts_nsec, rem_nsec / 1000,
		  tmpbuffer);
	pd->logbuffer_head = (pd->logbuffer_head + 1) % LOG_BUFFER_ENTRIES;

abort:
	mutex_unlock(&pd->logbuffer_lock);
}

static void pd_engine_log(struct usbpd *pd, const char *fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	_pd_engine_log(pd, fmt, args);
	va_end(args);
}

static int pd_engine_seq_show(struct seq_file *s, void *v)
{
	struct usbpd *pd = (struct usbpd *)s->private;
	int tail;

	mutex_lock(&pd->logbuffer_lock);
	tail = pd->logbuffer_tail;
	while (tail != pd->logbuffer_head) {
		seq_printf(s, "%s\n", pd->logbuffer[tail]);
		tail = (tail + 1) % LOG_BUFFER_ENTRIES;
	}
	if (!seq_has_overflowed(s))
		pd->logbuffer_tail = tail;
	mutex_unlock(&pd->logbuffer_lock);

	return 0;
}

static int pd_engine_debug_open(struct inode *inode, struct file *file)
{
	return single_open(file, pd_engine_seq_show, inode->i_private);
}

static const struct file_operations pd_engine_debug_operations = {
	.open		= pd_engine_debug_open,
	.llseek		= seq_lseek,
	.read		= seq_read,
	.release	= single_release,
};

static struct dentry *rootdir;

static int pd_engine_debugfs_init(struct usbpd *pd)
{
	mutex_init(&pd->logbuffer_lock);
	/* /sys/kernel/debug/pd_engine/usbpdX */
	if (!rootdir) {
		rootdir = debugfs_create_dir("pd_engine", NULL);
		if (!rootdir)
			return -ENOMEM;
	}

	pd->dentry = debugfs_create_file(dev_name(&pd->dev),
					 S_IFREG | S_IRUGO, rootdir,
					 pd, &pd_engine_debug_operations);

	return 0;
}

static void pd_engine_debugfs_exit(struct usbpd *pd)
{
	debugfs_remove(pd->dentry);
}

static const char * const get_typec_mode_name(
		enum power_supply_typec_mode typec_mode)
{
	switch (typec_mode) {
	case POWER_SUPPLY_TYPEC_NONE:
		return "NONE";
	case POWER_SUPPLY_TYPEC_SOURCE_DEFAULT:
		return "SOURCE_DEFAULT";
	case POWER_SUPPLY_TYPEC_SOURCE_MEDIUM:
		return "SOURCE_MEDIUM";
	case POWER_SUPPLY_TYPEC_SOURCE_HIGH:
		return "SOURCE_HIGH";
	case POWER_SUPPLY_TYPEC_NON_COMPLIANT:
		return "NON_COMPLIANT";
	case POWER_SUPPLY_TYPEC_SINK:
		return "SINK";
	case POWER_SUPPLY_TYPEC_SINK_POWERED_CABLE:
		return "SINK_POWERED_CABLE";
	case POWER_SUPPLY_TYPEC_SINK_DEBUG_ACCESSORY:
		return "SINK_DEBUG_ACCESSORY";
	case POWER_SUPPLY_TYPEC_SINK_AUDIO_ADAPTER:
		return "SINK_AUDIO_ADAPTER";
	case POWER_SUPPLY_TYPEC_POWERED_CABLE_ONLY:
		return "POWERED_CABLE_ONLY";
	default:
		return "UNDEFINED";
	}
}

static const char * const get_psy_type_name(enum power_supply_type psy_type)
{
	switch (psy_type) {
	case POWER_SUPPLY_TYPE_UNKNOWN:
		return "UNKNOWN";
	case POWER_SUPPLY_TYPE_USB:
		return "SDP";
	case POWER_SUPPLY_TYPE_USB_CDP:
		return "CDP";
	case POWER_SUPPLY_TYPE_USB_DCP:
		return "DCP";
	case POWER_SUPPLY_TYPE_USB_HVDCP:
		return "HVDCP2";
	case POWER_SUPPLY_TYPE_USB_HVDCP_3:
		return "HVDCP3";
	default:
		return "UNDEFINED";
	}
}

/* must align with smblib's integer representation of cc orientation. */
enum typec_cc_orientation {
	TYPEC_CC_ORIENTATION_NONE = 0,
	TYPEC_CC_ORIENTATION_CC1 = 1,
	TYPEC_CC_ORIENTATION_CC2 = 2,
};

static const char * const get_typec_cc_orientation_name(
		enum typec_cc_orientation typec_cc_orientation)
{
	switch (typec_cc_orientation) {
	case TYPEC_CC_ORIENTATION_NONE:
		return "NONE";
	case TYPEC_CC_ORIENTATION_CC1:
		return "CC1";
	case TYPEC_CC_ORIENTATION_CC2:
		return "CC2";
	default:
		return "UNDEFINED";
	}
}

static const char * const get_typec_cc_status_name(
		enum typec_cc_status cc_status)
{
	switch (cc_status) {
	case TYPEC_CC_OPEN:
		return "OPEN";
	case TYPEC_CC_RA:
		return "Ra";
	case TYPEC_CC_RD:
		return "Rd";
	case TYPEC_CC_RP_DEF:
		return "Rd-def";
	case TYPEC_CC_RP_1_5:
		return "Rd-1.5";
	case TYPEC_CC_RP_3_0:
		return "Rd-3.0";
	default:
		return "UNDEFINED";
	}
}

/*
 * parses the type-c mode to cc pin status in the orientation_none special case.
 */
static void parse_cc_status_none_orientation(
		enum power_supply_typec_mode typec_mode,
		enum typec_cc_status *cc1,
		enum typec_cc_status *cc2)
{
	switch (typec_mode) {
	case POWER_SUPPLY_TYPEC_SINK_DEBUG_ACCESSORY:
		*cc1 = *cc2 = TYPEC_CC_RD;
		break;
	case POWER_SUPPLY_TYPEC_SINK_AUDIO_ADAPTER:
		*cc1 = *cc2 = TYPEC_CC_RA;
		break;
	default:
		*cc1 = *cc2 = TYPEC_CC_OPEN;
		break;
	}
}

/*
 * parses the type-c mode to the status of the active and inactive cc pin.
 */
static void parse_cc_status_active_inactive(
		enum power_supply_typec_mode typec_mode,
		enum typec_cc_status *cc_active,
		enum typec_cc_status *cc_inactive)
{
	switch (typec_mode) {
	case POWER_SUPPLY_TYPEC_NONE:
		*cc_active = TYPEC_CC_OPEN;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	case POWER_SUPPLY_TYPEC_SOURCE_DEFAULT:
		*cc_active = TYPEC_CC_RP_DEF;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	case POWER_SUPPLY_TYPEC_SOURCE_MEDIUM:
		*cc_active = TYPEC_CC_RP_1_5;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	case POWER_SUPPLY_TYPEC_SOURCE_HIGH:
		*cc_active = TYPEC_CC_RP_3_0;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	case POWER_SUPPLY_TYPEC_NON_COMPLIANT:
		*cc_active = TYPEC_CC_OPEN;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	case POWER_SUPPLY_TYPEC_SINK:
		*cc_active = TYPEC_CC_RD;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	case POWER_SUPPLY_TYPEC_SINK_POWERED_CABLE:
		*cc_active = TYPEC_CC_RD;
		*cc_inactive = TYPEC_CC_RA;
		break;
	case POWER_SUPPLY_TYPEC_SINK_DEBUG_ACCESSORY:
		*cc_active = TYPEC_CC_RD;
		*cc_inactive = TYPEC_CC_RD;
		break;
	case POWER_SUPPLY_TYPEC_SINK_AUDIO_ADAPTER:
		*cc_active = TYPEC_CC_RA;
		*cc_inactive = TYPEC_CC_RA;
		break;
	case POWER_SUPPLY_TYPEC_POWERED_CABLE_ONLY:
		*cc_active = TYPEC_CC_RA;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	default:
		*cc_active = TYPEC_CC_OPEN;
		*cc_inactive = TYPEC_CC_OPEN;
		break;
	}
}

static void parse_cc_status(enum power_supply_typec_mode typec_mode,
			    enum typec_cc_orientation typec_cc_orientation,
			    enum typec_cc_status *cc1,
			    enum typec_cc_status *cc2)
{
	enum typec_cc_status cc_active, cc_inactive;

	/* handle orientation_none special cases */
	if (typec_cc_orientation == TYPEC_CC_ORIENTATION_NONE) {
		parse_cc_status_none_orientation(typec_mode, cc1, cc2);
		return;
	}

	parse_cc_status_active_inactive(typec_mode, &cc_active, &cc_inactive);

	/* assign cc1, cc2 status based on orientation */
	if (typec_cc_orientation == TYPEC_CC_ORIENTATION_CC1) {
		*cc1 = cc_active;
		*cc2 = cc_inactive;
	} else if (typec_cc_orientation == TYPEC_CC_ORIENTATION_CC2) {
		*cc1 = cc_inactive;
		*cc2 = cc_active;
	} else {
		*cc1 = *cc2 = TYPEC_CC_OPEN;
	}
}

static inline bool psy_support_usb_data(enum power_supply_type psy_type)
{
	return (psy_type == POWER_SUPPLY_TYPE_USB) ||
	       (psy_type == POWER_SUPPLY_TYPE_USB_CDP);
}

static int update_usb_data_role(struct usbpd *pd)
{
	int ret;
	bool extcon_usb;

	ret = extcon_set_cable_state_(pd->extcon, EXTCON_USB_CC,
				      pd->extcon_usb_cc);
	if (ret < 0) {
		pd_engine_log(pd, "unable to set extcon usb cc [%s], ret=%d",
			      pd->extcon_usb_cc ? "Y" : "N", ret);
		return ret;
	}
	ret = extcon_set_cable_state_(pd->extcon, EXTCON_USB_SPEED,
				      pd->extcon_usb_ss);
	if (ret < 0) {
		pd_engine_log(pd, "unable to set extcon usb ss [%s], ret=%d",
			      pd->extcon_usb_ss ? "Y" : "N", ret);
		return ret;
	}

	/* Turn on USB data (device role) only when a valid power supply that
	 * supports USB data connection is connected, i.e. SDP or CDP
	 *
	 * update_usb_data_role() is called when APSD is done, thus here
	 * pd->psy_type is a valid detection result.
	 */
	extcon_usb = pd->extcon_usb && psy_support_usb_data(pd->psy_type);

	/*
	 * EXTCON_USB_HOST and EXTCON_USB is mutually exlusive.
	 * Therefore while responding to commands such as DR_SWAP,
	 * update the cable state of the one being turned off before
	 * turning on the other one.
	 */
	if (!pd->extcon_usb_host) {
		ret = extcon_set_cable_state_(pd->extcon, EXTCON_USB_HOST,
					      pd->extcon_usb_host);
		if (ret < 0) {
			pd_engine_log(pd,
				"unable to set extcon usb host [%s], ret=%d",
				      pd->extcon_usb_host ? "Y" : "N", ret);
			return ret;
		}

		ret = extcon_set_cable_state_(pd->extcon, EXTCON_USB,
					      extcon_usb);
		if (ret < 0) {
			pd_engine_log(pd,
				      "unable to set extcon usb [%s], ret=%d",
				      extcon_usb ? "Y" : "N", ret);
			return ret;
		}
	} else {
		ret = extcon_set_cable_state_(pd->extcon, EXTCON_USB,
					      extcon_usb);
		if (ret < 0) {
			pd_engine_log(pd,
				      "unable to set extcon usb [%s], ret=%d",
				      extcon_usb ? "Y" : "N", ret);
			return ret;
		}

		ret = extcon_set_cable_state_(pd->extcon, EXTCON_USB_HOST,
					      pd->extcon_usb_host);
		if (ret < 0) {
			pd_engine_log(pd,
				"unable to set extcon usb host [%s], ret=%d",
				      pd->extcon_usb_host ? "Y" : "N", ret);
			return ret;
		}
	}

	pd_engine_log(pd,
		      "usb extcon: cc [%s], speed [%s], host [%s], usb [%s]",
		      pd->extcon_usb_cc ? "Y" : "N",
		      pd->extcon_usb_ss ? "Y" : "N",
		      pd->extcon_usb_host ? "Y" : "N",
		      extcon_usb ? "Y" : "N");

	return ret;
}

struct psy_changed_event {
	struct work_struct work;
	struct usbpd *pd;
};

static void psy_changed_handler(struct work_struct *work)
{
	struct psy_changed_event *event = container_of(work,
						       struct psy_changed_event,
						       work);
	struct usbpd *pd = event->pd;
	bool vbus_present;
	enum typec_cc_status cc1;
	enum typec_cc_status cc2;

	enum power_supply_type psy_type;
	enum power_supply_typec_mode typec_mode;
	enum typec_cc_orientation typec_cc_orientation;

	bool apsd_done;

	union power_supply_propval val;
	int ret = 0;

	ret = power_supply_get_property(pd->usb_psy,
					POWER_SUPPLY_PROP_TYPE, &val);
	if (ret < 0) {
		pd_engine_log(pd, "Unable to read TYPE, ret=%d", ret);
		return;
	}
	psy_type = val.intval;

	ret = power_supply_get_property(pd->usb_psy,
					POWER_SUPPLY_PROP_PD_APSD_DONE, &val);
	if (ret < 0) {
		pd_engine_log(pd, "Unable to read APSD_DONE, ret=%d",
			      ret);
		return;
	}
	apsd_done = !!val.intval;

	ret = power_supply_get_property(pd->usb_psy,
					POWER_SUPPLY_PROP_PRESENT, &val);
	if (ret < 0) {
		pd_engine_log(pd, "Unable to read PRESENT, ret=%d",
			      ret);
		return;
	}
	vbus_present = val.intval;

	ret = power_supply_get_property(pd->usb_psy,
					POWER_SUPPLY_PROP_TYPEC_MODE, &val);
	if (ret < 0) {
		pd_engine_log(pd, "Unable to read TYPEC_MODE, ret=%d",
			      ret);
		return;
	}
	typec_mode = val.intval;

	ret = power_supply_get_property(pd->usb_psy,
					POWER_SUPPLY_PROP_TYPEC_CC_ORIENTATION,
					&val);
	if (ret < 0) {
		pd_engine_log(pd,
			      "Unable to read TYPEC_CC_ORIENTATION, ret=%d",
			      ret);
		return;
	}
	typec_cc_orientation = val.intval;

	parse_cc_status(typec_mode, typec_cc_orientation, &cc1, &cc2);

	pd_engine_log(pd,
		      "type [%s], apsd done [%s], vbus present [%s], typec_mode [%s], typec_orientation [%s], cc1 [%s], cc2 [%s]",
		      get_psy_type_name(psy_type),
		      apsd_done ? "Y" : "N",
		      vbus_present ? "Y" : "N",
		      get_typec_mode_name(typec_mode),
		      get_typec_cc_orientation_name(typec_cc_orientation),
		      get_typec_cc_status_name(cc1),
		      get_typec_cc_status_name(cc2));

	mutex_lock(&pd->lock);

	pd->psy_type = psy_type;
	pd->is_cable_flipped = typec_cc_orientation == TYPEC_CC_ORIENTATION_CC2;
	pd->extcon_usb_cc = pd->is_cable_flipped;

	if (vbus_present != pd->vbus_present) {
		pd_engine_log(pd, "vbus present: %s -> %s",
			      pd->vbus_present ? "True" : "False",
			      vbus_present ? "True" : "False");
		pd->vbus_present = vbus_present;
		tcpm_vbus_change(pd->tcpm_port);
	}

	if (cc1 != pd->cc1 || cc2 != pd->cc2) {
		pd_engine_log(pd, "cc1: %s -> %s, cc2: %s -> %s",
			      get_typec_cc_status_name(pd->cc1),
			      get_typec_cc_status_name(cc1),
			      get_typec_cc_status_name(pd->cc2),
			      get_typec_cc_status_name(cc2));
		pd->cc1 = cc1;
		pd->cc2 = cc2;
		tcpm_cc_change(pd->tcpm_port);
	}

	if (apsd_done && pd->pending_update_usb_data) {
		pd_engine_log(pd,
			      "APSD is done now, update pending usb data role");
		ret = update_usb_data_role(pd);
		if (ret < 0)
			goto unlock;
		pd->pending_update_usb_data = false;
	}
unlock:
	kfree(event);
	mutex_unlock(&pd->lock);
}

static int psy_changed(struct notifier_block *nb, unsigned long evt, void *ptr)
{
	struct usbpd *pd;
	struct psy_changed_event *event;

	pd = container_of(nb, struct usbpd, psy_nb);
	if (ptr != pd->usb_psy || evt != PSY_EVENT_PROP_CHANGED)
		return 0;

	event = kzalloc(sizeof(*event), GFP_ATOMIC);
	if (!event)
		return -ENOMEM;

	INIT_WORK(&event->work, psy_changed_handler);
	event->pd = pd;
	queue_work(pd->wq, &event->work);

	return 0;
}

static int tcpm_init(struct tcpc_dev *dev)
{
	return 0;
}

static int tcpm_get_vbus(struct tcpc_dev *dev)
{
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	bool vbus_on;
	int ret;

	mutex_lock(&pd->lock);

	vbus_on = pd->vbus_present || pd->vbus_output;
	pd_engine_log(pd, "tcpm_get_vbus: %s",
		      vbus_on ? "True" : "False");
	ret = vbus_on ? 1 : 0;

	mutex_unlock(&pd->lock);
	return ret;
}

static int tcpm_set_cc(struct tcpc_dev *dev, enum typec_cc_status cc)
{
	union power_supply_propval val = {0};
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret = 0;

	mutex_lock(&pd->lock);

	switch (cc) {
	case TYPEC_CC_OPEN:
		val.intval = POWER_SUPPLY_TYPEC_PR_NONE;
		break;
	case TYPEC_CC_RD:
		val.intval = POWER_SUPPLY_TYPEC_PR_SINK;
		break;
	case TYPEC_CC_RP_DEF:
		val.intval = POWER_SUPPLY_TYPEC_PR_SOURCE;
		break;
	default:
		pd_engine_log(pd, "tcpm_set_cc: invalid cc %s",
			      get_typec_cc_status_name(cc));
		ret = -EINVAL;
		goto unlock;
	}
	ret = power_supply_set_property(pd->usb_psy,
					POWER_SUPPLY_PROP_TYPEC_POWER_ROLE,
					&val);
	if (ret < 0)
		pd_engine_log(pd, "unable to set POWER_ROLE, ret=%d",
			      ret);

unlock:
	mutex_unlock(&pd->lock);
	return ret;
}

static int tcpm_get_cc(struct tcpc_dev *dev, enum typec_cc_status *cc1,
		       enum typec_cc_status *cc2)
{
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);

	mutex_lock(&pd->lock);

	pd_engine_log(pd, "tcpm_get_cc: cc1=%s, cc2=%s",
		      get_typec_cc_status_name(pd->cc1),
		      get_typec_cc_status_name(pd->cc2));
	*cc1 = pd->cc1;
	*cc2 = pd->cc2;

	mutex_unlock(&pd->lock);
	return 0;
}

static int tcpm_set_polarity(struct tcpc_dev *dev,
			     enum typec_cc_polarity polarity)
{
	/* Hardware handles polarity, no op here. */
	return 0;
}

static int tcpm_set_vconn(struct tcpc_dev *dev, bool on)
{
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret = 0;

	mutex_lock(&pd->lock);

	if (on != pd->vconn_output) {
		if (on)
			ret = regulator_enable(pd->vconn);
		else
			ret = regulator_disable(pd->vconn);
		if (ret < 0) {
			pd_engine_log(pd, "unable to turn %s vconn, ret=%d",
				      on ? "on" : "off", ret);
			goto unlock;
		}
		pd->vconn_output = on;
	}

	pd_engine_log(pd, "set vconn: %s", on ? "on" : "off");

unlock:
	mutex_unlock(&pd->lock);
	return ret;
}

static int tcpm_set_vbus(struct tcpc_dev *dev, bool on, bool charge)
{
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret = 0;

	mutex_lock(&pd->lock);

	if (on != pd->vbus_output) {
		if (on)
			ret = regulator_enable(pd->vbus);
		else
			ret = regulator_disable(pd->vbus);
		if (ret < 0) {
			pd_engine_log(pd, "unable to turn %s vbus, ret=%d",
				      on ? "on" : "off", ret);
			goto unlock;
		}
		pd->vbus_output = on;
		/*
		 * No interrupt will be trigerred for the vbus change.
		 * Manually inform tcpm to check the vbus change.
		 */
		tcpm_vbus_change(pd->tcpm_port);
	}

	pd_engine_log(pd, "set vbus: %s", on ? "on" : "off");

unlock:
	mutex_unlock(&pd->lock);
	return ret;
}

static int tcpm_set_current_limit(struct tcpc_dev *dev, u32 max_ma, u32 mv)
{
	union power_supply_propval val = {0};
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret = 0;

	val.intval = mv * 1000;
	ret = power_supply_set_property(pd->usb_psy,
					POWER_SUPPLY_PROP_VOLTAGE_MAX,
					&val);
	if (ret < 0) {
		pd_engine_log(pd, "unable to set voltage to %d, ret=%d",
			      mv, ret);
		return ret;
	}

	val.intval = max_ma * 1000;
	ret = power_supply_set_property(pd->usb_psy,
					POWER_SUPPLY_PROP_PD_CURRENT_MAX,
					&val);
	if (ret < 0) {
		pd_engine_log(pd, "unable to set pd current max to %d, ret=%d",
			      max_ma, ret);
		return ret;
	}

	pd_engine_log(pd, "max_ma := %d, mv := %d", max_ma, mv);
	return ret;
}

static int tcpm_set_pd_rx(struct tcpc_dev *dev, bool on)
{
	union power_supply_propval val = {0};
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret = 0;

	if (pd->pdphy_open == on) {
		pd_engine_log(pd, "pd_phy already %s",
			      on ? "open" : "closed");
		return 0;
	}

	if (on) {
		ret = pd_phy_open(&pd->pdphy_params);
		if (ret < 0) {
			pd_engine_log(pd, "unable to %s pd_phy, ret=%d",
				      on ? "open" : "close", ret);
			return ret;
		}
		val.intval = 1;
	} else {
		/* pd_phy_close() has no return value. */
		pd_phy_close();
		val.intval = 0;
	}

	pd->pdphy_open = on;
	pd_engine_log(pd, "%s pd_phy", on ? "open" : "close");

	ret = power_supply_set_property(pd->usb_psy,
					POWER_SUPPLY_PROP_PD_CC_OVERRIDE,
					&val);
	if (ret < 0) {
		pd_engine_log(pd, "unable to set CC_OVERRIDE to %s, ret=%d",
			      on ? "true" : "false",
			      ret);
		return ret;
	}

	return 0;
}

static int get_data_len(__le16 header)
{
	int ret;

	ret = pd_header_cnt(__le16_to_cpu(header));
	ret *= 4;

	return ret;
}

static const char * const get_tcpm_transmit_type_name(
		enum tcpm_transmit_type type)
{
	switch (type) {
	case TCPC_TX_SOP:
		return "SOP";
	case TCPC_TX_SOP_PRIME:
		return "SOP_PRIME";
	case TCPC_TX_SOP_PRIME_PRIME:
		return "SOP_PRIME_PRIME";
	case TCPC_TX_SOP_DEBUG_PRIME:
		return "SOP_DEBUG_PRIME";
	case TCPC_TX_SOP_DEBUG_PRIME_PRIME:
		return "SOP_DEBUG_PRIME_PRIME";
	case TCPC_TX_HARD_RESET:
		return "HARD_RESET";
	case TCPC_TX_CABLE_RESET:
		return "CABLE_RESET";
	case TCPC_TX_BIST_MODE_2:
		return "BIST_MODE_2";
	default:
		return "UNDEFINED";
	}
}

struct pd_transmit_work {
	struct work_struct work;
	struct usbpd *pd;
	enum tcpm_transmit_type type;
	struct pd_message msg;
};

static const char * const get_tcpm_transmit_status_name(
		enum tcpm_transmit_status status)
{
	switch (status) {
	case TCPC_TX_SUCCESS:
		return "SUCCESS";
	case TCPC_TX_DISCARDED:
		return "DISCARDED";
	case TCPC_TX_FAILED:
		return "FAILED";
	default:
		return "UNDEFINED";
	}
}

#define PD_TX_TIMEOUT_MS (PD_T_TCPC_TX_TIMEOUT - 10)
static void pd_transmit_handler(struct work_struct *work)
{
	struct pd_transmit_work *pd_tx_work = container_of(work,
					struct pd_transmit_work,
					work);
	struct usbpd *pd = pd_tx_work->pd;
	enum tcpm_transmit_type type = pd_tx_work->type;
	struct pd_message *msg = &pd_tx_work->msg;
	enum tcpm_transmit_status status;
	bool signal;
	int ret = 0;

	switch (type) {
	case TCPC_TX_HARD_RESET:
		ret = pd_phy_signal(HARD_RESET_SIG, PD_TX_TIMEOUT_MS);
		signal = true;
		break;
	case TCPC_TX_CABLE_RESET:
		ret = pd_phy_signal(CABLE_RESET_SIG, PD_TX_TIMEOUT_MS);
		signal = true;
		break;
	case TCPC_TX_SOP:
		ret = pd_phy_write(msg->header, (u8 *)msg->payload,
				   get_data_len(msg->header),
				   SOP_MSG, PD_TX_TIMEOUT_MS);
		signal = false;
		break;
	case TCPC_TX_SOP_PRIME:
		ret = pd_phy_write(msg->header, (u8 *)msg->payload,
				   get_data_len(msg->header),
				   SOPI_MSG, PD_TX_TIMEOUT_MS);
		signal = false;
		break;
	case TCPC_TX_SOP_PRIME_PRIME:
		ret = pd_phy_write(msg->header, (u8 *)msg->payload,
				   get_data_len(msg->header),
				   SOPII_MSG, PD_TX_TIMEOUT_MS);
		signal = false;
		break;
	default:
		pd_engine_log(pd, "unknown pd tx type");
		kfree(pd_tx_work);
		return;
	}
	/*
	 * pd_phy_write()/pd_phy_signal() return value for hw irq event:
	 * - tx succeeded hw irq: 0 for signal or actual tx len for write
	 * - tx discarded hw irq: -EBUSY
	 * - tx failed hw irq: -EFAULT
	 */
	if (ret >= 0)
		status = TCPC_TX_SUCCESS;
	else if (ret == -EBUSY)
		status = TCPC_TX_DISCARDED;
	else
		status = TCPC_TX_FAILED;

	tcpm_pd_transmit_complete(pd->tcpm_port, status);

	if (signal)
		pd_engine_log(pd,
			      "pd tx type [%s], pdphy ret [%d], status [%s]",
			      get_tcpm_transmit_type_name(type),
			      ret, get_tcpm_transmit_status_name(status));
	else
		pd_engine_log(pd,
			      "pd tx header [%#x], type [%s], pdphy ret [%d], status [%s]",
			      msg->header, get_tcpm_transmit_type_name(type),
			      ret, get_tcpm_transmit_status_name(status));

	kfree(pd_tx_work);
}

static int tcpm_pd_transmit(struct tcpc_dev *dev, enum tcpm_transmit_type type,
			    const struct pd_message *msg)
{
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	struct pd_transmit_work *pd_tx_work;

	switch (type) {
	case TCPC_TX_HARD_RESET:
	case TCPC_TX_CABLE_RESET:
	case TCPC_TX_SOP:
	case TCPC_TX_SOP_PRIME:
	case TCPC_TX_SOP_PRIME_PRIME:
		break;
	default:
		pd_engine_log(pd, "unsupported pd type: %s",
			      get_tcpm_transmit_type_name(type));
		return -EINVAL;
	}

	pd_tx_work = kzalloc(sizeof(*pd_tx_work), GFP_ATOMIC);
	if (!pd_tx_work)
		return -ENOMEM;
	INIT_WORK(&pd_tx_work->work, pd_transmit_handler);
	pd_tx_work->pd = pd;
	pd_tx_work->type = type;
	if (msg)
		memcpy(&pd_tx_work->msg, msg, sizeof(*msg));
	queue_work(pd->wq, &pd_tx_work->work);

	if (msg)
		pd_engine_log(pd, "queue pd tx header [%#x], type [%s]",
			      msg->header, get_tcpm_transmit_type_name(type));
	else
		pd_engine_log(pd, "queue pd tx type [%s]",
			      get_tcpm_transmit_type_name(type));
	return 0;
}

static int tcpm_start_drp_toggling(struct tcpc_dev *dev,
				   enum typec_cc_status cc)
{
	/*
	 * Ignore the typec_cc_status for now. As current no
	 * src_pdo is configured, the default is Rp_def.
	 */
	union power_supply_propval val = {0};
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret;

	mutex_lock(&pd->lock);

	val.intval = POWER_SUPPLY_TYPEC_PR_DUAL;

	ret = power_supply_set_property(pd->usb_psy,
					POWER_SUPPLY_PROP_TYPEC_POWER_ROLE,
					&val);
	if (ret < 0) {
		pd_engine_log(pd, "unable to set POWER_ROLE to PR_DUAL, ret=%d",
			      ret);
		goto unlock;
	}

	pd->cc1 = TYPEC_CC_OPEN;
	pd->cc2 = TYPEC_CC_OPEN;

	pd_engine_log(pd, "start toggling");

unlock:
	mutex_unlock(&pd->lock);
	return ret;
}

static int tcpm_set_in_pr_swap(struct tcpc_dev *dev, bool pr_swap)
{
	union power_supply_propval val = {0};
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret;

	mutex_lock(&pd->lock);
	if (pd->in_pr_swap != pr_swap) {
		if (!pr_swap) {
			val.intval = POWER_SUPPLY_TYPEC_PR_DUAL;
			ret = power_supply_set_property(pd->usb_psy,
					POWER_SUPPLY_PROP_TYPEC_POWER_ROLE,
					&val);
			if (ret < 0) {
				pd_engine_log(pd,
				"unable to set POWER_ROLE to PR_DUAL, ret=%d",
					ret);
				goto unlock;
			}
			/* Required for the PMIC to recover */
			pd_engine_log(pd, "sleeping for 20mec");
			msleep(20);
		}
		val.intval = pr_swap ? 1 : 0;
		ret = power_supply_set_property(pd->usb_psy,
					POWER_SUPPLY_PROP_PR_SWAP,
					&val);
		if (ret < 0) {
			pd_engine_log(pd,
					"unable to set PR_SWAP to %d, ret=%d",
					pr_swap ? 1 : 0, ret);
			goto unlock;
		}

		pd->in_pr_swap = pr_swap;
		pd_engine_log(pd, "PR_SWAP = %d", pr_swap ? 1 : 0);
	}
unlock:
	mutex_unlock(&pd->lock);
	return ret;
}

static int tcpm_set_suspend_supported(struct tcpc_dev *dev,
				      bool suspend_supported)
{
	union power_supply_propval val = {0};
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret = 0;

	mutex_lock(&pd->lock);

	if (suspend_supported == pd->suspend_supported)
		goto unlock;

	/* Attempt once */
	pd->suspend_supported = suspend_supported;
	val.intval = suspend_supported ? 1 : 0;
	pd_engine_log(pd, "usb suspend %d", suspend_supported ? 1 : 0);
	ret = power_supply_set_property(pd->usb_psy,
				POWER_SUPPLY_PROP_PD_USB_SUSPEND_SUPPORTED,
				&val);
	if (ret < 0) {
		pd_engine_log(pd,
			      "unable to set suspend flag to %d, ret=%d",
			      suspend_supported ? 1 : 0, ret);
	}

unlock:
	mutex_unlock(&pd->lock);
	return ret;
}

enum power_role get_pdphy_power_role(enum typec_role role)
{
	switch (role) {
	case TYPEC_SINK:
		return PR_SINK;
	case TYPEC_SOURCE:
		return PR_SRC;
	default:
		return PR_NONE;
	}
}

static const char * const get_typec_role_name(enum typec_role role)
{
	switch (role) {
	case TYPEC_SINK:
		return "SINK";
	case TYPEC_SOURCE:
		return "SOURCE";
	default:
		return "UNDEFINED";
	}
}

static const char * const get_pdphy_pr_name(enum power_role pdphy_pr)
{
	switch (pdphy_pr) {
	case PR_SINK:
		return "PR_SINK";
	case PR_SRC:
		return "PR_SRC";
	case PR_NONE:
		return "PR_NONE";
	default:
		return "UNDEFINED";
	}
}

enum data_role get_pdphy_data_role(enum typec_data_role data)
{
	switch (data) {
	case TYPEC_DEVICE:
		return DR_UFP;
	case TYPEC_HOST:
		return DR_DFP;
	default:
		return DR_NONE;
	}
}

static const char * const get_typec_data_role_name(enum typec_data_role data)
{
	switch (data) {
	case TYPEC_DEVICE:
		return "DEVICE";
	case TYPEC_HOST:
		return "HOST";
	default:
		return "UNDEFINED";
	}
}

static const char * const get_pdphy_dr_name(enum data_role pdphy_dr)
{
	switch (pdphy_dr) {
	case DR_UFP:
		return "DR_UFP";
	case DR_DFP:
		return "DR_DFP";
	case DR_NONE:
		return "DR_NONE";
	default:
		return "UNDEFINED";
	}
}

static int set_pd_header(struct usbpd *pd, enum typec_role role,
			 enum typec_data_role data)
{
	enum power_role pdphy_pr;
	enum data_role pdphy_dr;
	int ret = 0;

	pdphy_pr = get_pdphy_power_role(role);
	pdphy_dr = get_pdphy_data_role(data);
	ret = pd_phy_update_roles(pdphy_dr, pdphy_pr);
	if (ret < 0) {
		pd_engine_log(pd, "unable to set pd_phy_header: %s, %s, ret=%d",
			      get_pdphy_pr_name(pdphy_pr),
			      get_pdphy_dr_name(pdphy_dr),
			      ret);
		return ret;
	}

	pd_engine_log(pd, "set pd_phy_header: %s, %s",
		      get_pdphy_pr_name(pdphy_pr),
		      get_pdphy_dr_name(pdphy_dr));

	return 0;
}

#define EXTCON_USB_SUPER_SPEED	true
static int set_usb_data_role(struct usbpd *pd, bool attached,
			     enum typec_role role,
			     enum typec_data_role data)
{
	int ret;
	union power_supply_propval val = {0};
	bool apsd_done;

	pd->extcon_usb_cc = pd->is_cable_flipped;
	pd->extcon_usb_ss = EXTCON_USB_SUPER_SPEED;

	if (!attached) {
		pd->extcon_usb = false;
		pd->extcon_usb_host = false;
	} else if (data == TYPEC_HOST) {
		pd->extcon_usb = false;
		pd->extcon_usb_host = true;
	} else {
		pd->extcon_usb = true;
		pd->extcon_usb_host = false;
	}

	ret = power_supply_get_property(pd->usb_psy,
					POWER_SUPPLY_PROP_PD_APSD_DONE,
					&val);
	if (ret < 0) {
		pd_engine_log(pd, "Unable to read APSD_DONE, ret=%d", ret);
		return ret;
	}

	if (val.intval == 0)
		apsd_done = false;
	else
		apsd_done = true;

	pd_engine_log(pd,
		      "set usb_data_role: power [%s], data [%s], apsd_done [%s], attached [%s]",
		      get_typec_role_name(role),
		      get_typec_data_role_name(data),
		      apsd_done ? "Y" : "N",
		      attached ? "Y" : "N");

	if (attached && role == TYPEC_SINK && !apsd_done) {
		/* wait for APSD done */
		pd_engine_log(pd,
			      "APSD is not done, delay update usb data role");
		pd->pending_update_usb_data = true;
	} else {
		ret = update_usb_data_role(pd);
		if (ret < 0)
			return ret;
		pd->pending_update_usb_data = false;
	}

	return ret;
}

static int tcpm_set_roles(struct tcpc_dev *dev, bool attached,
			  enum typec_role role, enum typec_data_role data)
{
	struct usbpd *pd = container_of(dev, struct usbpd, tcpc_dev);
	int ret;

	mutex_lock(&pd->lock);

	ret = set_pd_header(pd, role, data);
	if (ret < 0)
		goto unlock;

	ret = set_usb_data_role(pd, attached, role, data);

unlock:
	mutex_unlock(&pd->lock);
	return ret;
}

static void pd_phy_signal_rx(struct usbpd *pd, enum pd_sig_type type)
{
	switch (type) {
	case HARD_RESET_SIG:
		tcpm_pd_hard_reset(pd->tcpm_port);
		pd_engine_log(pd, "received pd hard reset");
		break;
	default:
		pd_engine_log(pd, "received unsupported signal: %d",
			      type);
		return;
	}
}

static void pd_phy_message_rx(struct usbpd *pd, enum pd_msg_type type,
			      u8 *buf, size_t len)
{
	struct pd_message msg;

	if (len < 2) {
		pd_engine_log(pd, "invalid message received, len=%ld",
			      len);
		return;
	}
	msg.header = cpu_to_le16(*((u16 *)buf));
	buf += sizeof(u16);
	len -= sizeof(u16);
	if (get_data_len(msg.header) != len) {
		pd_engine_log(pd, "header len %d != len %ld",
			      get_data_len(msg.header), len);
		return;
	}
	if (len > PD_MAX_PAYLOAD * 4) {
		pd_engine_log(pd, "len %ld > PD_MAX_PAYLOAD", len);
		return;
	}
	memcpy(msg.payload, buf, len);
	pd_engine_log(pd, "pd rx header [%#x]", msg.header);
	tcpm_pd_receive(pd->tcpm_port, &msg);
}

static void pd_phy_shutdown(struct usbpd *pd)
{
	pd_engine_log(pd, "pd phy shutdown");
}

enum pdo_role {
	SNK_PDO,
	SRC_PDO,
};

static const char * const pdo_prop_name[] = {
	[SNK_PDO]	= "snk-pdo",
	[SRC_PDO]	= "src-pdo",
};

#define PDO_FIXED_FLAGS \
	(PDO_FIXED_DUAL_ROLE | PDO_FIXED_DATA_SWAP | PDO_FIXED_USB_COMM)
/*
static const u32 src_pdo[] = {
	PDO_FIXED(5000, 900, PDO_FIXED_FLAGS),
};

static const u32 snk_pdo[] = {
	PDO_FIXED(5000, 3000, PDO_FIXED_FLAGS),
	PDO_FIXED(9000, 3000, PDO_FIXED_FLAGS),
};

static const struct tcpc_config pd_tcpc_config = {
	.src_pdo = src_pdo,
	.nr_src_pdo = ARRAY_SIZE(src_pdo),
	.snk_pdo = snk_pdo,
	.nr_snk_pdo = ARRAY_SIZE(snk_pdo),
	.max_snk_mv = 9000,
	.max_snk_ma = 3000,
	.max_snk_mw = 27000,
	.operating_snk_mw = 7600,
	.type = TYPEC_PORT_DRP,
	.default_role = TYPEC_SINK,
	.try_role_hw = true,
	.alt_modes = NULL,
};
*/

static u32 *parse_pdo(struct usbpd *pd, enum pdo_role role,
		      unsigned int *nr_pdo)
{
	struct device *dev = &pd->dev;
	u32 *dt_array;
	u32 *pdo;
	int i, count, rc;

	count = device_property_read_u32_array(dev->parent, pdo_prop_name[role],
					       NULL, 0);
	if (count > 0) {
		if (count % 4)
			return ERR_PTR(-EINVAL);

		*nr_pdo = count / 4;
		dt_array = devm_kcalloc(dev, count, sizeof(*dt_array),
					GFP_KERNEL);
		if (!dt_array)
			return ERR_PTR(-ENOMEM);

		rc = device_property_read_u32_array(dev->parent,
						    pdo_prop_name[role],
						    dt_array, count);
		if (rc)
			return ERR_PTR(rc);

		pdo = devm_kcalloc(dev, *nr_pdo, sizeof(*pdo), GFP_KERNEL);
		if (!pdo)
			return ERR_PTR(-ENOMEM);

		for (i = 0; i < *nr_pdo; i++) {
			switch (dt_array[i * 4]) {
			case PDO_TYPE_FIXED:
				pdo[i] = PDO_FIXED(dt_array[i * 4 + 1],
						   dt_array[i * 4 + 2],
						   PDO_FIXED_FLAGS);
				break;
			case PDO_TYPE_BATT:
				pdo[i] = PDO_BATT(dt_array[i * 4 + 1],
						  dt_array[i * 4 + 2],
						  dt_array[i * 4 + 3]);
				break;
			case PDO_TYPE_VAR:
				pdo[i] = PDO_VAR(dt_array[i * 4 + 1],
						 dt_array[i * 4 + 2],
						 dt_array[i * 4 + 3]);
				break;
			/*case PDO_TYPE_AUG:*/
			default:
				return ERR_PTR(-EINVAL);
			}
		}
		return pdo;
	}

	return ERR_PTR(-EINVAL);
}

static int init_tcpc_config(struct tcpc_dev *pd_tcpc_dev)
{
	struct usbpd *pd = container_of(pd_tcpc_dev, struct usbpd, tcpc_dev);
	struct device *dev = &pd->dev;
	struct tcpc_config *config;
	int ret;

	pd_tcpc_dev->config = devm_kzalloc(dev, sizeof(*config), GFP_KERNEL);
	if (!pd_tcpc_dev->config)
		return -ENOMEM;

	config = pd_tcpc_dev->config;

	ret = device_property_read_u32(dev->parent, "port-type", &config->type);
	if (ret < 0)
		return ret;

	switch (config->type) {
	case TYPEC_PORT_UFP:
		config->snk_pdo = parse_pdo(pd, SNK_PDO, &config->nr_snk_pdo);
		if (IS_ERR(config->snk_pdo))
			return PTR_ERR(config->snk_pdo);
		break;
	case TYPEC_PORT_DFP:
		config->src_pdo = parse_pdo(pd, SRC_PDO, &config->nr_src_pdo);
		if (IS_ERR(config->src_pdo))
			return PTR_ERR(config->src_pdo);
		break;
	case TYPEC_PORT_DRP:
		config->snk_pdo = parse_pdo(pd, SNK_PDO, &config->nr_snk_pdo);
		if (IS_ERR(config->snk_pdo))
			return PTR_ERR(config->snk_pdo);
		config->src_pdo = parse_pdo(pd, SRC_PDO, &config->nr_src_pdo);
		if (IS_ERR(config->src_pdo))
			return PTR_ERR(config->src_pdo);

		ret = device_property_read_u32(dev->parent, "default-role",
					       &config->default_role);
		if (ret < 0)
			return ret;

		config->try_role_hw = device_property_read_bool(dev->parent,
								"try-role-hw");
		break;
	default:
		return -EINVAL;
	}

	if (config->type == TYPEC_PORT_UFP || config->type == TYPEC_PORT_DRP) {
		ret = device_property_read_u32(dev->parent, "max-snk-mv",
					       &config->max_snk_mv);
		ret = device_property_read_u32(dev->parent, "max-snk-ma",
					       &config->max_snk_ma);
		ret = device_property_read_u32(dev->parent, "max-snk-mw",
					       &config->max_snk_mw);
		ret = device_property_read_u32(dev->parent, "op-snk-mw",
					       &config->operating_snk_mw);
		if (ret < 0)
			return ret;
	}

	/* TODO: parse alt mode from DT */
	config->alt_modes = NULL;

	return 0;
}

static int init_tcpc_dev(struct tcpc_dev *pd_tcpc_dev)
{
	int ret;

	ret = init_tcpc_config(pd_tcpc_dev);
	if (ret < 0)
		return ret;
	pd_tcpc_dev->init = tcpm_init;
	pd_tcpc_dev->get_vbus = tcpm_get_vbus;
	pd_tcpc_dev->set_cc = tcpm_set_cc;
	pd_tcpc_dev->get_cc = tcpm_get_cc;
	pd_tcpc_dev->set_polarity = tcpm_set_polarity;
	pd_tcpc_dev->set_vconn = tcpm_set_vconn;
	pd_tcpc_dev->set_vbus = tcpm_set_vbus;
	pd_tcpc_dev->set_current_limit = tcpm_set_current_limit;
	pd_tcpc_dev->set_pd_rx = tcpm_set_pd_rx;
	pd_tcpc_dev->set_roles = tcpm_set_roles;
	pd_tcpc_dev->try_role = NULL;
	pd_tcpc_dev->pd_transmit = tcpm_pd_transmit;
	pd_tcpc_dev->start_drp_toggling = tcpm_start_drp_toggling;
	pd_tcpc_dev->set_in_pr_swap = tcpm_set_in_pr_swap;
	pd_tcpc_dev->set_suspend_supported = tcpm_set_suspend_supported;
	pd_tcpc_dev->mux = NULL;
	return 0;
}

static void init_pd_phy_params(struct pd_phy_params *pdphy_params)
{
	pdphy_params->signal_cb = pd_phy_signal_rx;
	pdphy_params->msg_rx_cb = pd_phy_message_rx;
	pdphy_params->shutdown_cb = pd_phy_shutdown;
	pdphy_params->data_role = DR_UFP;
	pdphy_params->power_role = PR_SINK;
	pdphy_params->frame_filter_val = FRAME_FILTER_EN_SOP |
					 FRAME_FILTER_EN_HARD_RESET;
}

static const unsigned int usbpd_extcon_cable[] = {
	EXTCON_USB,
	EXTCON_USB_HOST,
	EXTCON_USB_CC,
	EXTCON_USB_SPEED,
	EXTCON_NONE,
};

/* EXTCON_USB and EXTCON_USB_HOST are mutually exclusive */
static const u32 usbpd_extcon_exclusive[] = {0x3, 0};

static int num_pd_instances;
/**
 * usbpd_create - Create a new instance of USB PD protocol/policy engine
 * @parent - parent device to associate with
 *
 * This creates a new usbpd class device which manages the state of a
 * USB PD-capable port. The parent device that is passed in should be
 * associated with the physical device port, e.g. a PD PHY.
 *
 * Derived from policy_engine.c.
 *
 * Return: struct usbpd pointer, or an ERR_PTR value
 */
struct usbpd *usbpd_create(struct device *parent)
{
	int ret;
	struct usbpd *pd;

	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
	if (!pd)
		return ERR_PTR(-ENOMEM);

	mutex_init(&pd->lock);

	device_initialize(&pd->dev);
	pd->dev.parent = parent;
	dev_set_drvdata(&pd->dev, pd);

	ret = dev_set_name(&pd->dev, "usbpd%d", num_pd_instances++);
	if (ret < 0)
		goto free_pd;

	ret = device_add(&pd->dev);
	if (ret < 0)
		goto free_pd;

	ret = pd_engine_debugfs_init(pd);
	if (ret < 0)
		goto del_pd;

	pd->vbus = devm_regulator_get(parent, "vbus");
	if (IS_ERR(pd->vbus)) {
		ret = PTR_ERR(pd->vbus);
		goto exit_debugfs;
	}

	pd->vconn = devm_regulator_get(parent, "vconn");
	if (IS_ERR(pd->vconn)) {
		ret = PTR_ERR(pd->vconn);
		goto exit_debugfs;
	}

	pd->extcon = devm_extcon_dev_allocate(parent, usbpd_extcon_cable);
	if (IS_ERR(pd->extcon)) {
		pd_engine_log(pd, "failed to allocate extcon device");
		ret = PTR_ERR(pd->extcon);
		goto exit_debugfs;
	}

	pd->extcon->mutually_exclusive = usbpd_extcon_exclusive;
	ret = devm_extcon_dev_register(parent, pd->extcon);
	if (ret < 0) {
		pd_engine_log(pd, "failed to register extcon device");
		goto exit_debugfs;
	}

	pd->wq = create_singlethread_workqueue(dev_name(&pd->dev));
	if (!pd->wq) {
		ret = -ENOMEM;
		goto exit_debugfs;
	}

	pd->usb_psy = power_supply_get_by_name("usb");
	if (!pd->usb_psy) {
		pd_engine_log(pd,
			      "Could not get USB power_supply, deferring probe");
		ret = -EPROBE_DEFER;
		goto del_wq;
	}

	/*
	 * TCPM callbacks may access pd->usb_psy. Therefore, tcpm_register_port
	 * must be called after pd->usb_psy is initialized.
	 */
	ret = init_tcpc_dev(&pd->tcpc_dev);
	if (ret < 0)
		goto put_psy;
	pd->tcpm_port = tcpm_register_port(&pd->dev, &pd->tcpc_dev);
	if (IS_ERR(pd->tcpm_port)) {
		ret = PTR_ERR(pd->tcpm_port);
		goto put_psy;
	}

	psy_changed(&pd->psy_nb, PSY_EVENT_PROP_CHANGED, pd->usb_psy);

	pd->psy_nb.notifier_call = psy_changed;
	ret = power_supply_reg_notifier(&pd->psy_nb);
	if (ret < 0)
		goto unreg_tcpm;

	init_pd_phy_params(&pd->pdphy_params);

	pd->suspend_supported = true;

	return pd;

unreg_tcpm:
	tcpm_unregister_port(pd->tcpm_port);
put_psy:
	power_supply_put(pd->usb_psy);
del_wq:
	destroy_workqueue(pd->wq);
exit_debugfs:
	pd_engine_debugfs_exit(pd);
del_pd:
	device_del(&pd->dev);
free_pd:
	num_pd_instances--;
	kfree(pd);
	return ERR_PTR(ret);
}
EXPORT_SYMBOL(usbpd_create);

/**
 * usbpd_destroy - Removes and frees a usbpd instance
 * @pd: the instance to destroy
 *
 * Derived from policy_engine.c.
 */
void usbpd_destroy(struct usbpd *pd)
{
	if (!pd)
		return;
	power_supply_unreg_notifier(&pd->psy_nb);
	tcpm_unregister_port(pd->tcpm_port);
	power_supply_put(pd->usb_psy);
	destroy_workqueue(pd->wq);
	pd_engine_debugfs_exit(pd);
	device_del(&pd->dev);
	num_pd_instances--;
	kfree(pd);
}
EXPORT_SYMBOL(usbpd_destroy);

static int __init pd_engine_init(void)
{
	return 0;
}
module_init(pd_engine_init);

static void __exit pd_engine_exit(void) {}
module_exit(pd_engine_exit);

MODULE_DESCRIPTION("USB PD Engine based on Type-C Port Manager");
MODULE_LICENSE("GPL v2");