// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2020 - 2022, Google LLC
*
* MAXIM TCPCI based TCPC driver
*/
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/usb/pd.h>
#include <linux/usb/tcpci.h>
#include <linux/usb/tcpm.h>
#include <linux/usb/typec.h>
#include "tcpci_maxim.h"
#define PD_ACTIVITY_TIMEOUT_MS 10000
#define TCPC_VENDOR_ALERT 0x80
#define TCPC_VENDOR_USBSW_CTRL 0x93
#define TCPC_VENDOR_USBSW_CTRL_ENABLE_USB_DATA 0x9
#define TCPC_VENDOR_USBSW_CTRL_DISABLE_USB_DATA 0
#define TCPC_RECEIVE_BUFFER_COUNT_OFFSET 0
#define TCPC_RECEIVE_BUFFER_FRAME_TYPE_OFFSET 1
#define TCPC_RECEIVE_BUFFER_RX_BYTE_BUF_OFFSET 2
/*
* LongMessage not supported, hence 32 bytes for buf to be read from RECEIVE_BUFFER.
* DEVICE_CAPABILITIES_2.LongMessage = 0, the value in READABLE_BYTE_COUNT reg shall be
* less than or equal to 31. Since, RECEIVE_BUFFER len = 31 + 1(READABLE_BYTE_COUNT).
*/
#define TCPC_RECEIVE_BUFFER_LEN 32
#define MAX_BUCK_BOOST_SID 0x69
#define MAX_BUCK_BOOST_OP 0xb9
#define MAX_BUCK_BOOST_OFF 0
#define MAX_BUCK_BOOST_SOURCE 0xa
#define MAX_BUCK_BOOST_SINK 0x5
static const struct regmap_range max_tcpci_tcpci_range[] = {
regmap_reg_range(0x00, 0x95)
};
static const struct regmap_access_table max_tcpci_tcpci_write_table = {
.yes_ranges = max_tcpci_tcpci_range,
.n_yes_ranges = ARRAY_SIZE(max_tcpci_tcpci_range),
};
static const struct regmap_config max_tcpci_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0x95,
.wr_table = &max_tcpci_tcpci_write_table,
};
static struct max_tcpci_chip *tdata_to_max_tcpci(struct tcpci_data *tdata)
{
return container_of(tdata, struct max_tcpci_chip, data);
}
static void max_tcpci_init_regs(struct max_tcpci_chip *chip)
{
u16 alert_mask = 0;
int ret;
ret = max_tcpci_write16(chip, TCPC_ALERT, 0xffff);
if (ret < 0) {
dev_err(chip->dev, "Error writing to TCPC_ALERT ret:%d\n", ret);
return;
}
ret = max_tcpci_write16(chip, TCPC_VENDOR_ALERT, 0xffff);
if (ret < 0) {
dev_err(chip->dev, "Error writing to TCPC_VENDOR_ALERT ret:%d\n", ret);
return;
}
ret = max_tcpci_write8(chip, TCPC_ALERT_EXTENDED, 0xff);
if (ret < 0) {
dev_err(chip->dev, "Unable to clear TCPC_ALERT_EXTENDED ret:%d\n", ret);
return;
}
/* Enable VSAFE0V detection */
ret = max_tcpci_write8(chip, TCPC_EXTENDED_STATUS_MASK, TCPC_EXTENDED_STATUS_VSAFE0V);
if (ret < 0) {
dev_err(chip->dev, "Unable to unmask TCPC_EXTENDED_STATUS_VSAFE0V ret:%d\n", ret);
return;
}
/* Vconn Over Current Protection */
ret = max_tcpci_write8(chip, TCPC_FAULT_STATUS_MASK, TCPC_FAULT_STATUS_MASK_VCONN_OC);
if (ret < 0)
return;
alert_mask = (TCPC_ALERT_TX_SUCCESS | TCPC_ALERT_TX_DISCARDED |
TCPC_ALERT_TX_FAILED | TCPC_ALERT_RX_HARD_RST |
TCPC_ALERT_RX_STATUS | TCPC_ALERT_POWER_STATUS |
TCPC_ALERT_CC_STATUS |
TCPC_ALERT_EXTND | TCPC_ALERT_EXTENDED_STATUS |
TCPC_ALERT_VBUS_DISCNCT | TCPC_ALERT_RX_BUF_OVF |
TCPC_ALERT_FAULT);
ret = max_tcpci_write16(chip, TCPC_ALERT_MASK, alert_mask);
if (ret < 0) {
dev_err(chip->dev,
"Error enabling TCPC_ALERT: TCPC_ALERT_MASK write failed ret:%d\n", ret);
return;
}
/* Enable vbus voltage monitoring and voltage alerts */
ret = max_tcpci_write8(chip, TCPC_POWER_CTRL, 0);
if (ret < 0) {
dev_err(chip->dev, "Error writing to TCPC_POWER_CTRL ret:%d\n", ret);
return;
}
ret = max_tcpci_write8(chip, TCPC_ALERT_EXTENDED_MASK, TCPC_SINK_FAST_ROLE_SWAP);
if (ret < 0)
return;
}
static void process_rx(struct max_tcpci_chip *chip, u16 status)
{
struct pd_message msg;
u8 count, frame_type, rx_buf[TCPC_RECEIVE_BUFFER_LEN];
int ret, payload_index;
u8 *rx_buf_ptr;
enum tcpm_transmit_type rx_type;
/*
* READABLE_BYTE_COUNT: Indicates the number of bytes in the RX_BUF_BYTE_x registers
* plus one (for the RX_BUF_FRAME_TYPE) Table 4-36.
* Read the count and frame type.
*/
ret = regmap_raw_read(chip->data.regmap, TCPC_RX_BYTE_CNT, rx_buf, 2);
if (ret < 0) {
dev_err(chip->dev, "TCPC_RX_BYTE_CNT read failed ret:%d\n", ret);
return;
}
count = rx_buf[TCPC_RECEIVE_BUFFER_COUNT_OFFSET];
frame_type = rx_buf[TCPC_RECEIVE_BUFFER_FRAME_TYPE_OFFSET];
switch (frame_type) {
case TCPC_RX_BUF_FRAME_TYPE_SOP1:
rx_type = TCPC_TX_SOP_PRIME;
break;
case TCPC_RX_BUF_FRAME_TYPE_SOP:
rx_type = TCPC_TX_SOP;
break;
default:
rx_type = TCPC_TX_SOP;
break;
}
if (count == 0 || (frame_type != TCPC_RX_BUF_FRAME_TYPE_SOP &&
frame_type != TCPC_RX_BUF_FRAME_TYPE_SOP1)) {
max_tcpci_write16(chip, TCPC_ALERT, TCPC_ALERT_RX_STATUS);
dev_err(chip->dev, "%s\n", count == 0 ? "error: count is 0" :
"error frame_type is not SOP/SOP'");
return;
}
if (count > sizeof(struct pd_message) || count + 1 > TCPC_RECEIVE_BUFFER_LEN) {
dev_err(chip->dev, "Invalid TCPC_RX_BYTE_CNT %d\n", count);
return;
}
/*
* Read count + 1 as RX_BUF_BYTE_x is hidden and can only be read through
* TCPC_RX_BYTE_CNT
*/
count += 1;
ret = regmap_raw_read(chip->data.regmap, TCPC_RX_BYTE_CNT, rx_buf, count);
if (ret < 0) {
dev_err(chip->dev, "Error: TCPC_RX_BYTE_CNT read failed: %d\n", ret);
return;
}
rx_buf_ptr = rx_buf + TCPC_RECEIVE_BUFFER_RX_BYTE_BUF_OFFSET;
msg.header = cpu_to_le16(*(u16 *)rx_buf_ptr);
rx_buf_ptr = rx_buf_ptr + sizeof(msg.header);
for (payload_index = 0; payload_index < pd_header_cnt_le(msg.header); payload_index++,
rx_buf_ptr += sizeof(msg.payload[0]))
msg.payload[payload_index] = cpu_to_le32(*(u32 *)rx_buf_ptr);
/*
* Read complete, clear RX status alert bit.
* Clear overflow as well if set.
*/
ret = max_tcpci_write16(chip, TCPC_ALERT,
TCPC_ALERT_RX_STATUS | (status & TCPC_ALERT_RX_BUF_OVF));
if (ret < 0)
return;
tcpm_pd_receive(chip->port, &msg, rx_type);
}
static int max_tcpci_set_vbus(struct tcpci *tcpci, struct tcpci_data *tdata, bool source, bool sink)
{
struct max_tcpci_chip *chip = tdata_to_max_tcpci(tdata);
u8 buffer_source[2] = {MAX_BUCK_BOOST_OP, MAX_BUCK_BOOST_SOURCE};
u8 buffer_sink[2] = {MAX_BUCK_BOOST_OP, MAX_BUCK_BOOST_SINK};
u8 buffer_none[2] = {MAX_BUCK_BOOST_OP, MAX_BUCK_BOOST_OFF};
struct i2c_client *i2c = chip->client;
int ret;
struct i2c_msg msgs[] = {
{
.addr = MAX_BUCK_BOOST_SID,
.flags = i2c->flags & I2C_M_TEN,
.len = 2,
.buf = source ? buffer_source : sink ? buffer_sink : buffer_none,
},
};
if (source && sink) {
dev_err(chip->dev, "Both source and sink set\n");
return -EINVAL;
}
ret = i2c_transfer(i2c->adapter, msgs, 1);
return ret < 0 ? ret : 1;
}
static void process_power_status(struct max_tcpci_chip *chip)
{
u8 pwr_status;
int ret;
ret = max_tcpci_read8(chip, TCPC_POWER_STATUS, &pwr_status);
if (ret < 0)
return;
if (pwr_status == 0xff)
max_tcpci_init_regs(chip);
else if (pwr_status & TCPC_POWER_STATUS_SOURCING_VBUS)
tcpm_sourcing_vbus(chip->port);
else
tcpm_vbus_change(chip->port);
}
static void max_tcpci_frs_sourcing_vbus(struct tcpci *tcpci, struct tcpci_data *tdata)
{
/*
* For Fast Role Swap case, Boost turns on autonomously without
* AP intervention, but, needs AP to enable source mode explicitly
* for AP to regain control.
*/
max_tcpci_set_vbus(tcpci, tdata, true, false);
}
static void process_tx(struct max_tcpci_chip *chip, u16 status)
{
if (status & TCPC_ALERT_TX_SUCCESS)
tcpm_pd_transmit_complete(chip->port, TCPC_TX_SUCCESS);
else if (status & TCPC_ALERT_TX_DISCARDED)
tcpm_pd_transmit_complete(chip->port, TCPC_TX_DISCARDED);
else if (status & TCPC_ALERT_TX_FAILED)
tcpm_pd_transmit_complete(chip->port, TCPC_TX_FAILED);
/* Reinit regs as Hard reset sets them to default value */
if ((status & TCPC_ALERT_TX_SUCCESS) && (status & TCPC_ALERT_TX_FAILED))
max_tcpci_init_regs(chip);
}
/* Enable USB switches when partner is USB communications capable */
static void max_tcpci_set_partner_usb_comm_capable(struct tcpci *tcpci, struct tcpci_data *data,
bool capable)
{
struct max_tcpci_chip *chip = tdata_to_max_tcpci(data);
int ret;
ret = max_tcpci_write8(chip, TCPC_VENDOR_USBSW_CTRL, capable ?
TCPC_VENDOR_USBSW_CTRL_ENABLE_USB_DATA :
TCPC_VENDOR_USBSW_CTRL_DISABLE_USB_DATA);
if (ret < 0)
dev_err(chip->dev, "Failed to enable USB switches");
}
static irqreturn_t _max_tcpci_irq(struct max_tcpci_chip *chip, u16 status)
{
u16 mask;
int ret;
u8 reg_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) {
mask = status & ~(TCPC_ALERT_RX_STATUS
| (status & TCPC_ALERT_RX_BUF_OVF));
ret = max_tcpci_write16(chip, TCPC_ALERT, mask);
if (ret < 0) {
dev_err(chip->dev, "ALERT clear failed\n");
return ret;
}
}
if (status & TCPC_ALERT_RX_BUF_OVF && !(status & TCPC_ALERT_RX_STATUS)) {
ret = max_tcpci_write16(chip, TCPC_ALERT, (TCPC_ALERT_RX_STATUS |
TCPC_ALERT_RX_BUF_OVF));
if (ret < 0) {
dev_err(chip->dev, "ALERT clear failed\n");
return ret;
}
}
if (status & TCPC_ALERT_FAULT) {
ret = max_tcpci_read8(chip, TCPC_FAULT_STATUS, ®_status);
if (ret < 0)
return ret;
ret = max_tcpci_write8(chip, TCPC_FAULT_STATUS, reg_status);
if (ret < 0)
return ret;
if (reg_status & TCPC_FAULT_STATUS_VCONN_OC) {
chip->veto_vconn_swap = true;
tcpm_port_error_recovery(chip->port);
}
}
if (status & TCPC_ALERT_EXTND) {
ret = max_tcpci_read8(chip, TCPC_ALERT_EXTENDED, ®_status);
if (ret < 0)
return ret;
ret = max_tcpci_write8(chip, TCPC_ALERT_EXTENDED, reg_status);
if (ret < 0)
return ret;
if (reg_status & TCPC_SINK_FAST_ROLE_SWAP) {
dev_info(chip->dev, "FRS Signal\n");
tcpm_sink_frs(chip->port);
}
}
if (status & TCPC_ALERT_EXTENDED_STATUS) {
ret = max_tcpci_read8(chip, TCPC_EXTENDED_STATUS, (u8 *)®_status);
if (ret >= 0 && (reg_status & TCPC_EXTENDED_STATUS_VSAFE0V))
tcpm_vbus_change(chip->port);
}
if (status & TCPC_ALERT_RX_STATUS)
process_rx(chip, status);
if (status & TCPC_ALERT_VBUS_DISCNCT)
tcpm_vbus_change(chip->port);
if (status & TCPC_ALERT_CC_STATUS) {
bool cc_handled = false;
if (chip->contaminant_state == DETECTED || tcpm_port_is_toggling(chip->port)) {
if (!max_contaminant_is_contaminant(chip, false, &cc_handled))
tcpm_port_clean(chip->port);
}
if (!cc_handled)
tcpm_cc_change(chip->port);
}
if (status & TCPC_ALERT_POWER_STATUS)
process_power_status(chip);
if (status & TCPC_ALERT_RX_HARD_RST) {
tcpm_pd_hard_reset(chip->port);
max_tcpci_init_regs(chip);
}
if (status & TCPC_ALERT_TX_SUCCESS || status & TCPC_ALERT_TX_DISCARDED || status &
TCPC_ALERT_TX_FAILED)
process_tx(chip, status);
return IRQ_HANDLED;
}
static irqreturn_t max_tcpci_irq(int irq, void *dev_id)
{
struct max_tcpci_chip *chip = dev_id;
u16 status;
irqreturn_t irq_return = IRQ_HANDLED;
int ret;
if (!chip->port)
return IRQ_HANDLED;
ret = max_tcpci_read16(chip, TCPC_ALERT, &status);
if (ret < 0) {
dev_err(chip->dev, "ALERT read failed\n");
return ret;
}
while (status) {
irq_return = _max_tcpci_irq(chip, status);
/* Do not return if a (new) ALERT is set (again). */
ret = max_tcpci_read16(chip, TCPC_ALERT, &status);
if (ret < 0)
break;
}
return irq_return;
}
static irqreturn_t max_tcpci_isr(int irq, void *dev_id)
{
struct max_tcpci_chip *chip = dev_id;
pm_wakeup_event(chip->dev, PD_ACTIVITY_TIMEOUT_MS);
if (!chip->port)
return IRQ_HANDLED;
return IRQ_WAKE_THREAD;
}
static int max_tcpci_init_alert(struct max_tcpci_chip *chip, struct i2c_client *client)
{
int ret;
ret = devm_request_threaded_irq(chip->dev, client->irq, max_tcpci_isr, max_tcpci_irq,
(IRQF_TRIGGER_LOW | IRQF_ONESHOT), dev_name(chip->dev),
chip);
if (ret < 0)
return ret;
enable_irq_wake(client->irq);
return 0;
}
static int max_tcpci_start_toggling(struct tcpci *tcpci, struct tcpci_data *tdata,
enum typec_cc_status cc)
{
struct max_tcpci_chip *chip = tdata_to_max_tcpci(tdata);
max_tcpci_init_regs(chip);
return 0;
}
static int tcpci_init(struct tcpci *tcpci, struct tcpci_data *data)
{
/*
* Generic TCPCI overwrites the regs once this driver initializes
* them. Prevent this by returning -1.
*/
return -1;
}
static void max_tcpci_check_contaminant(struct tcpci *tcpci, struct tcpci_data *tdata)
{
struct max_tcpci_chip *chip = tdata_to_max_tcpci(tdata);
bool cc_handled;
if (!max_contaminant_is_contaminant(chip, true, &cc_handled))
tcpm_port_clean(chip->port);
}
static bool max_tcpci_attempt_vconn_swap_discovery(struct tcpci *tcpci, struct tcpci_data *tdata)
{
struct max_tcpci_chip *chip = tdata_to_max_tcpci(tdata);
if (chip->veto_vconn_swap) {
chip->veto_vconn_swap = false;
return false;
}
return true;
}
static void max_tcpci_unregister_tcpci_port(void *tcpci)
{
tcpci_unregister_port(tcpci);
}
static int max_tcpci_probe(struct i2c_client *client)
{
int ret;
struct max_tcpci_chip *chip;
u8 power_status;
chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->client = client;
chip->data.regmap = devm_regmap_init_i2c(client, &max_tcpci_regmap_config);
if (IS_ERR(chip->data.regmap))
return dev_err_probe(&client->dev, PTR_ERR(chip->data.regmap),
"Regmap init failed\n");
chip->dev = &client->dev;
i2c_set_clientdata(client, chip);
ret = max_tcpci_read8(chip, TCPC_POWER_STATUS, &power_status);
if (ret < 0)
return dev_err_probe(&client->dev, ret,
"Failed to read TCPC_POWER_STATUS\n");
/* Chip level tcpci callbacks */
chip->data.set_vbus = max_tcpci_set_vbus;
chip->data.start_drp_toggling = max_tcpci_start_toggling;
chip->data.TX_BUF_BYTE_x_hidden = true;
chip->data.init = tcpci_init;
chip->data.frs_sourcing_vbus = max_tcpci_frs_sourcing_vbus;
chip->data.auto_discharge_disconnect = true;
chip->data.vbus_vsafe0v = true;
chip->data.set_partner_usb_comm_capable = max_tcpci_set_partner_usb_comm_capable;
chip->data.check_contaminant = max_tcpci_check_contaminant;
chip->data.cable_comm_capable = true;
chip->data.attempt_vconn_swap_discovery = max_tcpci_attempt_vconn_swap_discovery;
max_tcpci_init_regs(chip);
chip->tcpci = tcpci_register_port(chip->dev, &chip->data);
if (IS_ERR(chip->tcpci))
return dev_err_probe(&client->dev, PTR_ERR(chip->tcpci),
"TCPCI port registration failed\n");
ret = devm_add_action_or_reset(&client->dev,
max_tcpci_unregister_tcpci_port,
chip->tcpci);
if (ret)
return ret;
chip->port = tcpci_get_tcpm_port(chip->tcpci);
ret = max_tcpci_init_alert(chip, client);
if (ret < 0)
return dev_err_probe(&client->dev, ret,
"IRQ initialization failed\n");
device_init_wakeup(chip->dev, true);
return 0;
}
static const struct i2c_device_id max_tcpci_id[] = {
{ "maxtcpc" },
{ }
};
MODULE_DEVICE_TABLE(i2c, max_tcpci_id);
#ifdef CONFIG_OF
static const struct of_device_id max_tcpci_of_match[] = {
{ .compatible = "maxim,max33359", },
{},
};
MODULE_DEVICE_TABLE(of, max_tcpci_of_match);
#endif
static struct i2c_driver max_tcpci_i2c_driver = {
.driver = {
.name = "maxtcpc",
.of_match_table = of_match_ptr(max_tcpci_of_match),
},
.probe = max_tcpci_probe,
.id_table = max_tcpci_id,
};
module_i2c_driver(max_tcpci_i2c_driver);
MODULE_AUTHOR("Badhri Jagan Sridharan <[email protected]>");
MODULE_DESCRIPTION("Maxim TCPCI based USB Type-C Port Controller Interface Driver");
MODULE_LICENSE("GPL v2");
Codebase Browser
linux