diff options
Diffstat (limited to 'drivers/staging/typec/tcpci.c')
| -rw-r--r-- | drivers/staging/typec/tcpci.c | 526 |
1 files changed, 526 insertions, 0 deletions
diff --git a/drivers/staging/typec/tcpci.c b/drivers/staging/typec/tcpci.c new file mode 100644 index 000000000000..5e5be74c7850 --- /dev/null +++ b/drivers/staging/typec/tcpci.c @@ -0,0 +1,526 @@ +/* + * Copyright 2015-2017 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. + * + * 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/regmap.h> +#include <linux/usb/typec.h> + +#include "pd.h" +#include "tcpci.h" +#include "tcpm.h" + +#define PD_RETRY_COUNT 3 + +struct tcpci { + struct device *dev; + struct i2c_client *client; + + struct tcpm_port *port; + + struct regmap *regmap; + + bool controls_vbus; + + struct tcpc_dev tcpc; +}; + +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, + unsigned int *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_drp_toggling(struct tcpc_dev *tcpc, + enum typec_cc_status cc) +{ + struct tcpci *tcpci = tcpc_to_tcpci(tcpc); + unsigned int reg = TCPC_ROLE_CTRL_DRP; + + 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; + } + + return regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg); +} + +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; + 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, ®); + 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); + int ret; + + ret = regmap_write(tcpci->regmap, TCPC_TCPC_CTRL, + (polarity == TYPEC_POLARITY_CC2) ? + TCPC_TCPC_CTRL_ORIENTATION : 0); + if (ret < 0) + return ret; + + return 0; +} + +static int tcpci_set_vconn(struct tcpc_dev *tcpc, bool enable) +{ + struct tcpci *tcpci = tcpc_to_tcpci(tcpc); + int ret; + + ret = regmap_write(tcpci->regmap, TCPC_POWER_CTRL, + enable ? TCPC_POWER_CTRL_VCONN_ENABLE : 0); + if (ret < 0) + return ret; + + return 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, ®); + 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); + unsigned int reg, cnt, header; + int ret; + + cnt = msg ? pd_header_cnt(msg->header) * 4 : 0; + ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2); + if (ret < 0) + return ret; + + header = msg ? msg->header : 0; + 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, ®); + if (ret < 0) + return ret; + if (!(reg & TCPC_POWER_STATUS_UNINIT)) + break; + usleep_range(10000, 20000); + } + if (time_after(jiffies, timeout)) + return -ETIMEDOUT; + + /* 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; + + 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); +} + +static irqreturn_t tcpci_irq(int irq, void *dev_id) +{ + struct tcpci *tcpci = dev_id; + unsigned int status, reg; + + 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) { + regmap_read(tcpci->regmap, TCPC_POWER_STATUS_MASK, ®); + + /* + * 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; + + regmap_read(tcpci->regmap, TCPC_RX_BYTE_CNT, &cnt); + + tcpci_read16(tcpci, TCPC_RX_HDR, ®); + msg.header = reg; + + if (WARN_ON(cnt > sizeof(msg.payload))) + cnt = sizeof(msg.payload); + + if (cnt > 0) + regmap_raw_read(tcpci->regmap, TCPC_RX_DATA, + &msg.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; +} + +static const struct regmap_config tcpci_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .max_register = 0x7F, /* 0x80 .. 0xFF are vendor defined */ +}; + +const struct tcpc_config tcpci_tcpc_config = { + .type = TYPEC_PORT_DFP, + .default_role = TYPEC_SINK, +}; + +static int tcpci_parse_config(struct tcpci *tcpci) +{ + tcpci->controls_vbus = true; /* XXX */ + + /* TODO: Populate struct tcpc_config from ACPI/device-tree */ + tcpci->tcpc.config = &tcpci_tcpc_config; + + return 0; +} + +static int tcpci_probe(struct i2c_client *client, + const struct i2c_device_id *i2c_id) +{ + struct tcpci *tcpci; + int err; + + tcpci = devm_kzalloc(&client->dev, sizeof(*tcpci), GFP_KERNEL); + if (!tcpci) + return -ENOMEM; + + tcpci->client = client; + tcpci->dev = &client->dev; + i2c_set_clientdata(client, tcpci); + tcpci->regmap = devm_regmap_init_i2c(client, &tcpci_regmap_config); + if (IS_ERR(tcpci->regmap)) + return PTR_ERR(tcpci->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_drp_toggling = tcpci_start_drp_toggling; + + tcpci->tcpc.set_pd_rx = tcpci_set_pd_rx; + tcpci->tcpc.set_roles = tcpci_set_roles; + tcpci->tcpc.pd_transmit = tcpci_pd_transmit; + + err = tcpci_parse_config(tcpci); + if (err < 0) + return err; + + /* Disable chip interrupts */ + tcpci_write16(tcpci, TCPC_ALERT_MASK, 0); + + err = devm_request_threaded_irq(tcpci->dev, client->irq, NULL, + tcpci_irq, + IRQF_ONESHOT | IRQF_TRIGGER_LOW, + dev_name(tcpci->dev), tcpci); + if (err < 0) + return err; + + tcpci->port = tcpm_register_port(tcpci->dev, &tcpci->tcpc); + return PTR_ERR_OR_ZERO(tcpci->port); +} + +static int tcpci_remove(struct i2c_client *client) +{ + struct tcpci *tcpci = i2c_get_clientdata(client); + + tcpm_unregister_port(tcpci->port); + + 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 = "usb,tcpci", }, + {}, +}; +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"); |