drivers/usb/typec/tcpm/tcpci.c - pub/scm/linux/kernel/git/gustavoars/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright 2015-2017 Google, Inc
  *
  * USB Type-C Port Controller Interface.
  */

 #include <linux/delay.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/usb/pd.h>
 #include <linux/usb/tcpm.h>
 #include <linux/usb/typec.h>

 #include "tcpci.h"

 #define PD_RETRY_COUNT 3

 struct tcpci {
 	struct device *dev;

 	struct tcpm_port *port;

 	struct regmap *regmap;

 	bool controls_vbus;

 	struct tcpc_dev tcpc;
 	struct tcpci_data *data;
 };

 struct tcpci_chip {
 	struct tcpci *tcpci;
 	struct tcpci_data data;
 };

 static inline struct tcpci *tcpc_to_tcpci(struct tcpc_dev *tcpc)
 {
 	return container_of(tcpc, struct tcpci, tcpc);
 }

 static int tcpci_read16(struct tcpci *tcpci, unsigned int reg, u16 *val)
 {
 	return regmap_raw_read(tcpci->regmap, reg, val, sizeof(u16));
 }

 static int tcpci_write16(struct tcpci *tcpci, unsigned int reg, u16 val)
 {
 	return regmap_raw_write(tcpci->regmap, reg, &val, sizeof(u16));
 }

 static int tcpci_set_cc(struct tcpc_dev *tcpc, enum typec_cc_status cc)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned int reg;
 	int ret;

 	switch (cc) {
 	case TYPEC_CC_RA:
 		reg = (TCPC_ROLE_CTRL_CC_RA << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			(TCPC_ROLE_CTRL_CC_RA << TCPC_ROLE_CTRL_CC2_SHIFT);
 		break;
 	case TYPEC_CC_RD:
 		reg = (TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			(TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC2_SHIFT);
 		break;
 	case TYPEC_CC_RP_DEF:
 		reg = (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			(TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT) |
 			(TCPC_ROLE_CTRL_RP_VAL_DEF <<
 			 TCPC_ROLE_CTRL_RP_VAL_SHIFT);
 		break;
 	case TYPEC_CC_RP_1_5:
 		reg = (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			(TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT) |
 			(TCPC_ROLE_CTRL_RP_VAL_1_5 <<
 			 TCPC_ROLE_CTRL_RP_VAL_SHIFT);
 		break;
 	case TYPEC_CC_RP_3_0:
 		reg = (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			(TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT) |
 			(TCPC_ROLE_CTRL_RP_VAL_3_0 <<
 			 TCPC_ROLE_CTRL_RP_VAL_SHIFT);
 		break;
 	case TYPEC_CC_OPEN:
 	default:
 		reg = (TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			(TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC2_SHIFT);
 		break;
 	}

 	ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int tcpci_start_toggling(struct tcpc_dev *tcpc,
 				enum typec_port_type port_type,
 				enum typec_cc_status cc)
 {
 	int ret;
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned int reg = TCPC_ROLE_CTRL_DRP;

 	if (port_type != TYPEC_PORT_DRP)
 		return -EOPNOTSUPP;

 	/* Handle vendor drp toggling */
 	if (tcpci->data->start_drp_toggling) {
 		ret = tcpci->data->start_drp_toggling(tcpci, tcpci->data, cc);
 		if (ret < 0)
 			return ret;
 	}

 	switch (cc) {
 	default:
 	case TYPEC_CC_RP_DEF:
 		reg |= (TCPC_ROLE_CTRL_RP_VAL_DEF <<
 			TCPC_ROLE_CTRL_RP_VAL_SHIFT);
 		break;
 	case TYPEC_CC_RP_1_5:
 		reg |= (TCPC_ROLE_CTRL_RP_VAL_1_5 <<
 			TCPC_ROLE_CTRL_RP_VAL_SHIFT);
 		break;
 	case TYPEC_CC_RP_3_0:
 		reg |= (TCPC_ROLE_CTRL_RP_VAL_3_0 <<
 			TCPC_ROLE_CTRL_RP_VAL_SHIFT);
 		break;
 	}

 	if (cc == TYPEC_CC_RD)
 		reg |= (TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			   (TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC2_SHIFT);
 	else
 		reg |= (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) |
 			   (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT);
 	ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
 	if (ret < 0)
 		return ret;
 	return regmap_write(tcpci->regmap, TCPC_COMMAND,
 			    TCPC_CMD_LOOK4CONNECTION);
 }

 static enum typec_cc_status tcpci_to_typec_cc(unsigned int cc, bool sink)
 {
 	switch (cc) {
 	case 0x1:
 		return sink ? TYPEC_CC_RP_DEF : TYPEC_CC_RA;
 	case 0x2:
 		return sink ? TYPEC_CC_RP_1_5 : TYPEC_CC_RD;
 	case 0x3:
 		if (sink)
 			return TYPEC_CC_RP_3_0;
 		fallthrough;
 	case 0x0:
 	default:
 		return TYPEC_CC_OPEN;
 	}
 }

 static int tcpci_get_cc(struct tcpc_dev *tcpc,
 			enum typec_cc_status *cc1, enum typec_cc_status *cc2)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned int reg;
 	int ret;

 	ret = regmap_read(tcpci->regmap, TCPC_CC_STATUS, &reg);
 	if (ret < 0)
 		return ret;

 	*cc1 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC1_SHIFT) &
 				 TCPC_CC_STATUS_CC1_MASK,
 				 reg & TCPC_CC_STATUS_TERM);
 	*cc2 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC2_SHIFT) &
 				 TCPC_CC_STATUS_CC2_MASK,
 				 reg & TCPC_CC_STATUS_TERM);

 	return 0;
 }

 static int tcpci_set_polarity(struct tcpc_dev *tcpc,
 			      enum typec_cc_polarity polarity)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned int reg;
 	int ret;

 	/* Keep the disconnect cc line open */
 	ret = regmap_read(tcpci->regmap, TCPC_ROLE_CTRL, &reg);
 	if (ret < 0)
 		return ret;

 	if (polarity == TYPEC_POLARITY_CC2)
 		reg |= TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC1_SHIFT;
 	else
 		reg |= TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC2_SHIFT;
 	ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
 	if (ret < 0)
 		return ret;

 	return regmap_write(tcpci->regmap, TCPC_TCPC_CTRL,
 			   (polarity == TYPEC_POLARITY_CC2) ?
 			   TCPC_TCPC_CTRL_ORIENTATION : 0);
 }

 static int tcpci_set_vconn(struct tcpc_dev *tcpc, bool enable)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	int ret;

 	/* Handle vendor set vconn */
 	if (tcpci->data->set_vconn) {
 		ret = tcpci->data->set_vconn(tcpci, tcpci->data, enable);
 		if (ret < 0)
 			return ret;
 	}

 	return regmap_update_bits(tcpci->regmap, TCPC_POWER_CTRL,
 				TCPC_POWER_CTRL_VCONN_ENABLE,
 				enable ? TCPC_POWER_CTRL_VCONN_ENABLE : 0);
 }

 static int tcpci_set_bist_data(struct tcpc_dev *tcpc, bool enable)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);

 	return regmap_update_bits(tcpci->regmap, TCPC_TCPC_CTRL, TCPC_TCPC_CTRL_BIST_TM,
 				 enable ? TCPC_TCPC_CTRL_BIST_TM : 0);
 }

 static int tcpci_set_roles(struct tcpc_dev *tcpc, bool attached,
 			   enum typec_role role, enum typec_data_role data)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned int reg;
 	int ret;

 	reg = PD_REV20 << TCPC_MSG_HDR_INFO_REV_SHIFT;
 	if (role == TYPEC_SOURCE)
 		reg |= TCPC_MSG_HDR_INFO_PWR_ROLE;
 	if (data == TYPEC_HOST)
 		reg |= TCPC_MSG_HDR_INFO_DATA_ROLE;
 	ret = regmap_write(tcpci->regmap, TCPC_MSG_HDR_INFO, reg);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int tcpci_set_pd_rx(struct tcpc_dev *tcpc, bool enable)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned int reg = 0;
 	int ret;

 	if (enable)
 		reg = TCPC_RX_DETECT_SOP | TCPC_RX_DETECT_HARD_RESET;
 	ret = regmap_write(tcpci->regmap, TCPC_RX_DETECT, reg);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int tcpci_get_vbus(struct tcpc_dev *tcpc)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned int reg;
 	int ret;

 	ret = regmap_read(tcpci->regmap, TCPC_POWER_STATUS, &reg);
 	if (ret < 0)
 		return ret;

 	return !!(reg & TCPC_POWER_STATUS_VBUS_PRES);
 }

 static int tcpci_set_vbus(struct tcpc_dev *tcpc, bool source, bool sink)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	int ret;

 	/* Disable both source and sink first before enabling anything */

 	if (!source) {
 		ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
 				   TCPC_CMD_DISABLE_SRC_VBUS);
 		if (ret < 0)
 			return ret;
 	}

 	if (!sink) {
 		ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
 				   TCPC_CMD_DISABLE_SINK_VBUS);
 		if (ret < 0)
 			return ret;
 	}

 	if (source) {
 		ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
 				   TCPC_CMD_SRC_VBUS_DEFAULT);
 		if (ret < 0)
 			return ret;
 	}

 	if (sink) {
 		ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
 				   TCPC_CMD_SINK_VBUS);
 		if (ret < 0)
 			return ret;
 	}

 	return 0;
 }

 static int tcpci_pd_transmit(struct tcpc_dev *tcpc,
 			     enum tcpm_transmit_type type,
 			     const struct pd_message *msg)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	u16 header = msg ? le16_to_cpu(msg->header) : 0;
 	unsigned int reg, cnt;
 	int ret;

 	cnt = msg ? pd_header_cnt(header) * 4 : 0;
 	ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2);
 	if (ret < 0)
 		return ret;

 	ret = tcpci_write16(tcpci, TCPC_TX_HDR, header);
 	if (ret < 0)
 		return ret;

 	if (cnt > 0) {
 		ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA,
 				       &msg->payload, cnt);
 		if (ret < 0)
 			return ret;
 	}

 	reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) |
 		(type << TCPC_TRANSMIT_TYPE_SHIFT);
 	ret = regmap_write(tcpci->regmap, TCPC_TRANSMIT, reg);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int tcpci_init(struct tcpc_dev *tcpc)
 {
 	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
 	unsigned long timeout = jiffies + msecs_to_jiffies(2000); /* XXX */
 	unsigned int reg;
 	int ret;

 	while (time_before_eq(jiffies, timeout)) {
 		ret = regmap_read(tcpci->regmap, TCPC_POWER_STATUS, &reg);
 		if (ret < 0)
 			return ret;
 		if (!(reg & TCPC_POWER_STATUS_UNINIT))
 			break;
 		usleep_range(10000, 20000);
 	}
 	if (time_after(jiffies, timeout))
 		return -ETIMEDOUT;

 	/* Handle vendor init */
 	if (tcpci->data->init) {
 		ret = tcpci->data->init(tcpci, tcpci->data);
 		if (ret < 0)
 			return ret;
 	}

 	/* Clear all events */
 	ret = tcpci_write16(tcpci, TCPC_ALERT, 0xffff);
 	if (ret < 0)
 		return ret;

 	if (tcpci->controls_vbus)
 		reg = TCPC_POWER_STATUS_VBUS_PRES;
 	else
 		reg = 0;
 	ret = regmap_write(tcpci->regmap, TCPC_POWER_STATUS_MASK, reg);
 	if (ret < 0)
 		return ret;

 	/* Enable Vbus detection */
 	ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
 			   TCPC_CMD_ENABLE_VBUS_DETECT);
 	if (ret < 0)
 		return ret;

 	reg = TCPC_ALERT_TX_SUCCESS | TCPC_ALERT_TX_FAILED |
 		TCPC_ALERT_TX_DISCARDED | TCPC_ALERT_RX_STATUS |
 		TCPC_ALERT_RX_HARD_RST | TCPC_ALERT_CC_STATUS;
 	if (tcpci->controls_vbus)
 		reg |= TCPC_ALERT_POWER_STATUS;
 	return tcpci_write16(tcpci, TCPC_ALERT_MASK, reg);
 }

 irqreturn_t tcpci_irq(struct tcpci *tcpci)
 {
 	u16 status;

 	tcpci_read16(tcpci, TCPC_ALERT, &status);

 	/*
 	 * Clear alert status for everything except RX_STATUS, which shouldn't
 	 * be cleared until we have successfully retrieved message.
 	 */
 	if (status & ~TCPC_ALERT_RX_STATUS)
 		tcpci_write16(tcpci, TCPC_ALERT,
 			      status & ~TCPC_ALERT_RX_STATUS);

 	if (status & TCPC_ALERT_CC_STATUS)
 		tcpm_cc_change(tcpci->port);

 	if (status & TCPC_ALERT_POWER_STATUS) {
 		unsigned int reg;

 		regmap_read(tcpci->regmap, TCPC_POWER_STATUS_MASK, &reg);

 		/*
 		 * If power status mask has been reset, then the TCPC
 		 * has reset.
 		 */
 		if (reg == 0xff)
 			tcpm_tcpc_reset(tcpci->port);
 		else
 			tcpm_vbus_change(tcpci->port);
 	}

 	if (status & TCPC_ALERT_RX_STATUS) {
 		struct pd_message msg;
 		unsigned int cnt, payload_cnt;
 		u16 header;

 		regmap_read(tcpci->regmap, TCPC_RX_BYTE_CNT, &cnt);
 		/*
 		 * 'cnt' corresponds to READABLE_BYTE_COUNT in section 4.4.14
 		 * of the TCPCI spec [Rev 2.0 Ver 1.0 October 2017] and is
 		 * defined in table 4-36 as one greater than the number of
 		 * bytes received. And that number includes the header. So:
 		 */
 		if (cnt > 3)
 			payload_cnt = cnt - (1 + sizeof(msg.header));
 		else
 			payload_cnt = 0;

 		tcpci_read16(tcpci, TCPC_RX_HDR, &header);
 		msg.header = cpu_to_le16(header);

 		if (WARN_ON(payload_cnt > sizeof(msg.payload)))
 			payload_cnt = sizeof(msg.payload);

 		if (payload_cnt > 0)
 			regmap_raw_read(tcpci->regmap, TCPC_RX_DATA,
 					&msg.payload, payload_cnt);

 		/* Read complete, clear RX status alert bit */
 		tcpci_write16(tcpci, TCPC_ALERT, TCPC_ALERT_RX_STATUS);

 		tcpm_pd_receive(tcpci->port, &msg);
 	}

 	if (status & TCPC_ALERT_RX_HARD_RST)
 		tcpm_pd_hard_reset(tcpci->port);

 	if (status & TCPC_ALERT_TX_SUCCESS)
 		tcpm_pd_transmit_complete(tcpci->port, TCPC_TX_SUCCESS);
 	else if (status & TCPC_ALERT_TX_DISCARDED)
 		tcpm_pd_transmit_complete(tcpci->port, TCPC_TX_DISCARDED);
 	else if (status & TCPC_ALERT_TX_FAILED)
 		tcpm_pd_transmit_complete(tcpci->port, TCPC_TX_FAILED);

 	return IRQ_HANDLED;
 }
 EXPORT_SYMBOL_GPL(tcpci_irq);

 static irqreturn_t _tcpci_irq(int irq, void *dev_id)
 {
 	struct tcpci_chip *chip = dev_id;

 	return tcpci_irq(chip->tcpci);
 }

 static const struct regmap_config tcpci_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,

 	.max_register = 0x7F, /* 0x80 .. 0xFF are vendor defined */
 };

 static int tcpci_parse_config(struct tcpci *tcpci)
 {
 	tcpci->controls_vbus = true; /* XXX */

 	tcpci->tcpc.fwnode = device_get_named_child_node(tcpci->dev,
 							 "connector");
 	if (!tcpci->tcpc.fwnode) {
 		dev_err(tcpci->dev, "Can't find connector node.\n");
 		return -EINVAL;
 	}

 	return 0;
 }

 struct tcpci *tcpci_register_port(struct device *dev, struct tcpci_data *data)
 {
 	struct tcpci *tcpci;
 	int err;

 	tcpci = devm_kzalloc(dev, sizeof(*tcpci), GFP_KERNEL);
 	if (!tcpci)
 		return ERR_PTR(-ENOMEM);

 	tcpci->dev = dev;
 	tcpci->data = data;
 	tcpci->regmap = data->regmap;

 	tcpci->tcpc.init = tcpci_init;
 	tcpci->tcpc.get_vbus = tcpci_get_vbus;
 	tcpci->tcpc.set_vbus = tcpci_set_vbus;
 	tcpci->tcpc.set_cc = tcpci_set_cc;
 	tcpci->tcpc.get_cc = tcpci_get_cc;
 	tcpci->tcpc.set_polarity = tcpci_set_polarity;
 	tcpci->tcpc.set_vconn = tcpci_set_vconn;
 	tcpci->tcpc.start_toggling = tcpci_start_toggling;

 	tcpci->tcpc.set_pd_rx = tcpci_set_pd_rx;
 	tcpci->tcpc.set_roles = tcpci_set_roles;
 	tcpci->tcpc.pd_transmit = tcpci_pd_transmit;
 	tcpci->tcpc.set_bist_data = tcpci_set_bist_data;

 	err = tcpci_parse_config(tcpci);
 	if (err < 0)
 		return ERR_PTR(err);

 	tcpci->port = tcpm_register_port(tcpci->dev, &tcpci->tcpc);
 	if (IS_ERR(tcpci->port))
 		return ERR_CAST(tcpci->port);

 	return tcpci;
 }
 EXPORT_SYMBOL_GPL(tcpci_register_port);

 void tcpci_unregister_port(struct tcpci *tcpci)
 {
 	tcpm_unregister_port(tcpci->port);
 }
 EXPORT_SYMBOL_GPL(tcpci_unregister_port);

 static int tcpci_probe(struct i2c_client *client,
 		       const struct i2c_device_id *i2c_id)
 {
 	struct tcpci_chip *chip;
 	int err;
 	u16 val = 0;

 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;

 	chip->data.regmap = devm_regmap_init_i2c(client, &tcpci_regmap_config);
 	if (IS_ERR(chip->data.regmap))
 		return PTR_ERR(chip->data.regmap);

 	i2c_set_clientdata(client, chip);

 	/* Disable chip interrupts before requesting irq */
 	err = regmap_raw_write(chip->data.regmap, TCPC_ALERT_MASK, &val,
 			       sizeof(u16));
 	if (err < 0)
 		return err;

 	chip->tcpci = tcpci_register_port(&client->dev, &chip->data);
 	if (IS_ERR(chip->tcpci))
 		return PTR_ERR(chip->tcpci);

 	err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
 					_tcpci_irq,
 					IRQF_ONESHOT | IRQF_TRIGGER_LOW,
 					dev_name(&client->dev), chip);
 	if (err < 0) {
 		tcpci_unregister_port(chip->tcpci);
 		return err;
 	}

 	return 0;
 }

 static int tcpci_remove(struct i2c_client *client)
 {
 	struct tcpci_chip *chip = i2c_get_clientdata(client);
 	int err;

 	/* Disable chip interrupts before unregistering port */
 	err = tcpci_write16(chip->tcpci, TCPC_ALERT_MASK, 0);
 	if (err < 0)
 		return err;

 	tcpci_unregister_port(chip->tcpci);

 	return 0;
 }

 static const struct i2c_device_id tcpci_id[] = {
 	{ "tcpci", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, tcpci_id);

 #ifdef CONFIG_OF
 static const struct of_device_id tcpci_of_match[] = {
 	{ .compatible = "nxp,ptn5110", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, tcpci_of_match);
 #endif

 static struct i2c_driver tcpci_i2c_driver = {
 	.driver = {
 		.name = "tcpci",
 		.of_match_table = of_match_ptr(tcpci_of_match),
 	},
 	.probe = tcpci_probe,
 	.remove = tcpci_remove,
 	.id_table = tcpci_id,
 };
 module_i2c_driver(tcpci_i2c_driver);

 MODULE_DESCRIPTION("USB Type-C Port Controller Interface driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Copyright 2015-2017 Google, Inc
	*
	* USB Type-C Port Controller Interface.
	*/

	#include <linux/delay.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/i2c.h>
	#include <linux/interrupt.h>
	#include <linux/property.h>
	#include <linux/regmap.h>
	#include <linux/usb/pd.h>
	#include <linux/usb/tcpm.h>
	#include <linux/usb/typec.h>

	#include "tcpci.h"

	#define PD_RETRY_COUNT 3

	struct tcpci {
	struct device *dev;

	struct tcpm_port *port;

	struct regmap *regmap;

	bool controls_vbus;

	struct tcpc_dev tcpc;
	struct tcpci_data *data;
	};

	struct tcpci_chip {
	struct tcpci *tcpci;
	struct tcpci_data data;
	};

	static inline struct tcpci tcpc_to_tcpci(struct tcpc_dev tcpc)
	{
	return container_of(tcpc, struct tcpci, tcpc);
	}

	static int tcpci_read16(struct tcpci tcpci, unsigned int reg, u16 val)
	{
	return regmap_raw_read(tcpci->regmap, reg, val, sizeof(u16));
	}

	static int tcpci_write16(struct tcpci *tcpci, unsigned int reg, u16 val)
	{
	return regmap_raw_write(tcpci->regmap, reg, &val, sizeof(u16));
	}

	static int tcpci_set_cc(struct tcpc_dev *tcpc, enum typec_cc_status cc)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg;
	int ret;

	switch (cc) {
	case TYPEC_CC_RA:
	reg = (TCPC_ROLE_CTRL_CC_RA << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_RA << TCPC_ROLE_CTRL_CC2_SHIFT);
	break;
	case TYPEC_CC_RD:
	reg = (TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC2_SHIFT);
	break;
	case TYPEC_CC_RP_DEF:
	reg = (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT) \|
	(TCPC_ROLE_CTRL_RP_VAL_DEF <<
	TCPC_ROLE_CTRL_RP_VAL_SHIFT);
	break;
	case TYPEC_CC_RP_1_5:
	reg = (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT) \|
	(TCPC_ROLE_CTRL_RP_VAL_1_5 <<
	TCPC_ROLE_CTRL_RP_VAL_SHIFT);
	break;
	case TYPEC_CC_RP_3_0:
	reg = (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT) \|
	(TCPC_ROLE_CTRL_RP_VAL_3_0 <<
	TCPC_ROLE_CTRL_RP_VAL_SHIFT);
	break;
	case TYPEC_CC_OPEN:
	default:
	reg = (TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC2_SHIFT);
	break;
	}

	ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int tcpci_start_toggling(struct tcpc_dev *tcpc,
	enum typec_port_type port_type,
	enum typec_cc_status cc)
	{
	int ret;
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg = TCPC_ROLE_CTRL_DRP;

	if (port_type != TYPEC_PORT_DRP)
	return -EOPNOTSUPP;

	/* Handle vendor drp toggling */
	if (tcpci->data->start_drp_toggling) {
	ret = tcpci->data->start_drp_toggling(tcpci, tcpci->data, cc);
	if (ret < 0)
	return ret;
	}

	switch (cc) {
	default:
	case TYPEC_CC_RP_DEF:
	reg \|= (TCPC_ROLE_CTRL_RP_VAL_DEF <<
	TCPC_ROLE_CTRL_RP_VAL_SHIFT);
	break;
	case TYPEC_CC_RP_1_5:
	reg \|= (TCPC_ROLE_CTRL_RP_VAL_1_5 <<
	TCPC_ROLE_CTRL_RP_VAL_SHIFT);
	break;
	case TYPEC_CC_RP_3_0:
	reg \|= (TCPC_ROLE_CTRL_RP_VAL_3_0 <<
	TCPC_ROLE_CTRL_RP_VAL_SHIFT);
	break;
	}

	if (cc == TYPEC_CC_RD)
	reg \|= (TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC2_SHIFT);
	else
	reg \|= (TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT) \|
	(TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT);
	ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
	if (ret < 0)
	return ret;
	return regmap_write(tcpci->regmap, TCPC_COMMAND,
	TCPC_CMD_LOOK4CONNECTION);
	}

	static enum typec_cc_status tcpci_to_typec_cc(unsigned int cc, bool sink)
	{
	switch (cc) {
	case 0x1:
	return sink ? TYPEC_CC_RP_DEF : TYPEC_CC_RA;
	case 0x2:
	return sink ? TYPEC_CC_RP_1_5 : TYPEC_CC_RD;
	case 0x3:
	if (sink)
	return TYPEC_CC_RP_3_0;
	fallthrough;
	case 0x0:
	default:
	return TYPEC_CC_OPEN;
	}
	}

	static int tcpci_get_cc(struct tcpc_dev *tcpc,
	enum typec_cc_status cc1, enum typec_cc_status cc2)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg;
	int ret;

	ret = regmap_read(tcpci->regmap, TCPC_CC_STATUS, &reg);
	if (ret < 0)
	return ret;

	*cc1 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC1_SHIFT) &
	TCPC_CC_STATUS_CC1_MASK,
	reg & TCPC_CC_STATUS_TERM);
	*cc2 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC2_SHIFT) &
	TCPC_CC_STATUS_CC2_MASK,
	reg & TCPC_CC_STATUS_TERM);

	return 0;
	}

	static int tcpci_set_polarity(struct tcpc_dev *tcpc,
	enum typec_cc_polarity polarity)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg;
	int ret;

	/* Keep the disconnect cc line open */
	ret = regmap_read(tcpci->regmap, TCPC_ROLE_CTRL, &reg);
	if (ret < 0)
	return ret;

	if (polarity == TYPEC_POLARITY_CC2)
	reg \|= TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC1_SHIFT;
	else
	reg \|= TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC2_SHIFT;
	ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
	if (ret < 0)
	return ret;

	return regmap_write(tcpci->regmap, TCPC_TCPC_CTRL,
	(polarity == TYPEC_POLARITY_CC2) ?
	TCPC_TCPC_CTRL_ORIENTATION : 0);
	}

	static int tcpci_set_vconn(struct tcpc_dev *tcpc, bool enable)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	int ret;

	/* Handle vendor set vconn */
	if (tcpci->data->set_vconn) {
	ret = tcpci->data->set_vconn(tcpci, tcpci->data, enable);
	if (ret < 0)
	return ret;
	}

	return regmap_update_bits(tcpci->regmap, TCPC_POWER_CTRL,
	TCPC_POWER_CTRL_VCONN_ENABLE,
	enable ? TCPC_POWER_CTRL_VCONN_ENABLE : 0);
	}

	static int tcpci_set_bist_data(struct tcpc_dev *tcpc, bool enable)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);

	return regmap_update_bits(tcpci->regmap, TCPC_TCPC_CTRL, TCPC_TCPC_CTRL_BIST_TM,
	enable ? TCPC_TCPC_CTRL_BIST_TM : 0);
	}

	static int tcpci_set_roles(struct tcpc_dev *tcpc, bool attached,
	enum typec_role role, enum typec_data_role data)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg;
	int ret;

	reg = PD_REV20 << TCPC_MSG_HDR_INFO_REV_SHIFT;
	if (role == TYPEC_SOURCE)
	reg \|= TCPC_MSG_HDR_INFO_PWR_ROLE;
	if (data == TYPEC_HOST)
	reg \|= TCPC_MSG_HDR_INFO_DATA_ROLE;
	ret = regmap_write(tcpci->regmap, TCPC_MSG_HDR_INFO, reg);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int tcpci_set_pd_rx(struct tcpc_dev *tcpc, bool enable)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg = 0;
	int ret;

	if (enable)
	reg = TCPC_RX_DETECT_SOP \| TCPC_RX_DETECT_HARD_RESET;
	ret = regmap_write(tcpci->regmap, TCPC_RX_DETECT, reg);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int tcpci_get_vbus(struct tcpc_dev *tcpc)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg;
	int ret;

	ret = regmap_read(tcpci->regmap, TCPC_POWER_STATUS, &reg);
	if (ret < 0)
	return ret;

	return !!(reg & TCPC_POWER_STATUS_VBUS_PRES);
	}

	static int tcpci_set_vbus(struct tcpc_dev *tcpc, bool source, bool sink)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	int ret;

	/* Disable both source and sink first before enabling anything */

	if (!source) {
	ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
	TCPC_CMD_DISABLE_SRC_VBUS);
	if (ret < 0)
	return ret;
	}

	if (!sink) {
	ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
	TCPC_CMD_DISABLE_SINK_VBUS);
	if (ret < 0)
	return ret;
	}

	if (source) {
	ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
	TCPC_CMD_SRC_VBUS_DEFAULT);
	if (ret < 0)
	return ret;
	}

	if (sink) {
	ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
	TCPC_CMD_SINK_VBUS);
	if (ret < 0)
	return ret;
	}

	return 0;
	}

	static int tcpci_pd_transmit(struct tcpc_dev *tcpc,
	enum tcpm_transmit_type type,
	const struct pd_message *msg)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	u16 header = msg ? le16_to_cpu(msg->header) : 0;
	unsigned int reg, cnt;
	int ret;

	cnt = msg ? pd_header_cnt(header) * 4 : 0;
	ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2);
	if (ret < 0)
	return ret;

	ret = tcpci_write16(tcpci, TCPC_TX_HDR, header);
	if (ret < 0)
	return ret;

	if (cnt > 0) {
	ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA,
	&msg->payload, cnt);
	if (ret < 0)
	return ret;
	}

	reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) \|
	(type << TCPC_TRANSMIT_TYPE_SHIFT);
	ret = regmap_write(tcpci->regmap, TCPC_TRANSMIT, reg);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int tcpci_init(struct tcpc_dev *tcpc)
	{
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned long timeout = jiffies + msecs_to_jiffies(2000); /* XXX */
	unsigned int reg;
	int ret;

	while (time_before_eq(jiffies, timeout)) {
	ret = regmap_read(tcpci->regmap, TCPC_POWER_STATUS, &reg);
	if (ret < 0)
	return ret;
	if (!(reg & TCPC_POWER_STATUS_UNINIT))
	break;
	usleep_range(10000, 20000);
	}
	if (time_after(jiffies, timeout))
	return -ETIMEDOUT;

	/* Handle vendor init */
	if (tcpci->data->init) {
	ret = tcpci->data->init(tcpci, tcpci->data);
	if (ret < 0)
	return ret;
	}

	/* Clear all events */
	ret = tcpci_write16(tcpci, TCPC_ALERT, 0xffff);
	if (ret < 0)
	return ret;

	if (tcpci->controls_vbus)
	reg = TCPC_POWER_STATUS_VBUS_PRES;
	else
	reg = 0;
	ret = regmap_write(tcpci->regmap, TCPC_POWER_STATUS_MASK, reg);
	if (ret < 0)
	return ret;

	/* Enable Vbus detection */
	ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
	TCPC_CMD_ENABLE_VBUS_DETECT);
	if (ret < 0)
	return ret;

	reg = TCPC_ALERT_TX_SUCCESS \| TCPC_ALERT_TX_FAILED \|
	TCPC_ALERT_TX_DISCARDED \| TCPC_ALERT_RX_STATUS \|
	TCPC_ALERT_RX_HARD_RST \| TCPC_ALERT_CC_STATUS;
	if (tcpci->controls_vbus)
	reg \|= TCPC_ALERT_POWER_STATUS;
	return tcpci_write16(tcpci, TCPC_ALERT_MASK, reg);
	}

	irqreturn_t tcpci_irq(struct tcpci *tcpci)
	{
	u16 status;

	tcpci_read16(tcpci, TCPC_ALERT, &status);

	/*
	* Clear alert status for everything except RX_STATUS, which shouldn't
	* be cleared until we have successfully retrieved message.
	*/
	if (status & ~TCPC_ALERT_RX_STATUS)
	tcpci_write16(tcpci, TCPC_ALERT,
	status & ~TCPC_ALERT_RX_STATUS);

	if (status & TCPC_ALERT_CC_STATUS)
	tcpm_cc_change(tcpci->port);

	if (status & TCPC_ALERT_POWER_STATUS) {
	unsigned int reg;

	regmap_read(tcpci->regmap, TCPC_POWER_STATUS_MASK, &reg);

	/*
	* If power status mask has been reset, then the TCPC
	* has reset.
	*/
	if (reg == 0xff)
	tcpm_tcpc_reset(tcpci->port);
	else
	tcpm_vbus_change(tcpci->port);
	}

	if (status & TCPC_ALERT_RX_STATUS) {
	struct pd_message msg;
	unsigned int cnt, payload_cnt;
	u16 header;

	regmap_read(tcpci->regmap, TCPC_RX_BYTE_CNT, &cnt);
	/*
	* 'cnt' corresponds to READABLE_BYTE_COUNT in section 4.4.14
	* of the TCPCI spec [Rev 2.0 Ver 1.0 October 2017] and is
	* defined in table 4-36 as one greater than the number of
	* bytes received. And that number includes the header. So:
	*/
	if (cnt > 3)
	payload_cnt = cnt - (1 + sizeof(msg.header));
	else
	payload_cnt = 0;

	tcpci_read16(tcpci, TCPC_RX_HDR, &header);
	msg.header = cpu_to_le16(header);

	if (WARN_ON(payload_cnt > sizeof(msg.payload)))
	payload_cnt = sizeof(msg.payload);

	if (payload_cnt > 0)
	regmap_raw_read(tcpci->regmap, TCPC_RX_DATA,
	&msg.payload, payload_cnt);

	/* Read complete, clear RX status alert bit */
	tcpci_write16(tcpci, TCPC_ALERT, TCPC_ALERT_RX_STATUS);

	tcpm_pd_receive(tcpci->port, &msg);
	}

	if (status & TCPC_ALERT_RX_HARD_RST)
	tcpm_pd_hard_reset(tcpci->port);

	if (status & TCPC_ALERT_TX_SUCCESS)
	tcpm_pd_transmit_complete(tcpci->port, TCPC_TX_SUCCESS);
	else if (status & TCPC_ALERT_TX_DISCARDED)
	tcpm_pd_transmit_complete(tcpci->port, TCPC_TX_DISCARDED);
	else if (status & TCPC_ALERT_TX_FAILED)
	tcpm_pd_transmit_complete(tcpci->port, TCPC_TX_FAILED);

	return IRQ_HANDLED;
	}
	EXPORT_SYMBOL_GPL(tcpci_irq);

	static irqreturn_t _tcpci_irq(int irq, void *dev_id)
	{
	struct tcpci_chip *chip = dev_id;

	return tcpci_irq(chip->tcpci);
	}

	static const struct regmap_config tcpci_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,

	.max_register = 0x7F, /* 0x80 .. 0xFF are vendor defined */
	};

	static int tcpci_parse_config(struct tcpci *tcpci)
	{
	tcpci->controls_vbus = true; /* XXX */

	tcpci->tcpc.fwnode = device_get_named_child_node(tcpci->dev,
	"connector");
	if (!tcpci->tcpc.fwnode) {
	dev_err(tcpci->dev, "Can't find connector node.\n");
	return -EINVAL;
	}

	return 0;
	}

	struct tcpci tcpci_register_port(struct device dev, struct tcpci_data *data)
	{
	struct tcpci *tcpci;
	int err;

	tcpci = devm_kzalloc(dev, sizeof(*tcpci), GFP_KERNEL);
	if (!tcpci)
	return ERR_PTR(-ENOMEM);

	tcpci->dev = dev;
	tcpci->data = data;
	tcpci->regmap = data->regmap;

	tcpci->tcpc.init = tcpci_init;
	tcpci->tcpc.get_vbus = tcpci_get_vbus;
	tcpci->tcpc.set_vbus = tcpci_set_vbus;
	tcpci->tcpc.set_cc = tcpci_set_cc;
	tcpci->tcpc.get_cc = tcpci_get_cc;
	tcpci->tcpc.set_polarity = tcpci_set_polarity;
	tcpci->tcpc.set_vconn = tcpci_set_vconn;
	tcpci->tcpc.start_toggling = tcpci_start_toggling;

	tcpci->tcpc.set_pd_rx = tcpci_set_pd_rx;
	tcpci->tcpc.set_roles = tcpci_set_roles;
	tcpci->tcpc.pd_transmit = tcpci_pd_transmit;
	tcpci->tcpc.set_bist_data = tcpci_set_bist_data;

	err = tcpci_parse_config(tcpci);
	if (err < 0)
	return ERR_PTR(err);

	tcpci->port = tcpm_register_port(tcpci->dev, &tcpci->tcpc);
	if (IS_ERR(tcpci->port))
	return ERR_CAST(tcpci->port);

	return tcpci;
	}
	EXPORT_SYMBOL_GPL(tcpci_register_port);

	void tcpci_unregister_port(struct tcpci *tcpci)
	{
	tcpm_unregister_port(tcpci->port);
	}
	EXPORT_SYMBOL_GPL(tcpci_unregister_port);

	static int tcpci_probe(struct i2c_client *client,
	const struct i2c_device_id *i2c_id)
	{
	struct tcpci_chip *chip;
	int err;
	u16 val = 0;

	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
	if (!chip)
	return -ENOMEM;

	chip->data.regmap = devm_regmap_init_i2c(client, &tcpci_regmap_config);
	if (IS_ERR(chip->data.regmap))
	return PTR_ERR(chip->data.regmap);

	i2c_set_clientdata(client, chip);

	/* Disable chip interrupts before requesting irq */
	err = regmap_raw_write(chip->data.regmap, TCPC_ALERT_MASK, &val,
	sizeof(u16));
	if (err < 0)
	return err;

	chip->tcpci = tcpci_register_port(&client->dev, &chip->data);
	if (IS_ERR(chip->tcpci))
	return PTR_ERR(chip->tcpci);

	err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
	_tcpci_irq,
	IRQF_ONESHOT \| IRQF_TRIGGER_LOW,
	dev_name(&client->dev), chip);
	if (err < 0) {
	tcpci_unregister_port(chip->tcpci);
	return err;
	}

	return 0;
	}

	static int tcpci_remove(struct i2c_client *client)
	{
	struct tcpci_chip *chip = i2c_get_clientdata(client);
	int err;

	/* Disable chip interrupts before unregistering port */
	err = tcpci_write16(chip->tcpci, TCPC_ALERT_MASK, 0);
	if (err < 0)
	return err;

	tcpci_unregister_port(chip->tcpci);

	return 0;
	}

	static const struct i2c_device_id tcpci_id[] = {
	{ "tcpci", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, tcpci_id);

	#ifdef CONFIG_OF
	static const struct of_device_id tcpci_of_match[] = {
	{ .compatible = "nxp,ptn5110", },
	{},
	};
	MODULE_DEVICE_TABLE(of, tcpci_of_match);
	#endif

	static struct i2c_driver tcpci_i2c_driver = {
	.driver = {
	.name = "tcpci",
	.of_match_table = of_match_ptr(tcpci_of_match),
	},
	.probe = tcpci_probe,
	.remove = tcpci_remove,
	.id_table = tcpci_id,
	};
	module_i2c_driver(tcpci_i2c_driver);

	MODULE_DESCRIPTION("USB Type-C Port Controller Interface driver");
	MODULE_LICENSE("GPL");