diff options
Diffstat (limited to 'drivers/usb/typec/ucsi/ucsi.c')
| -rw-r--r-- | drivers/usb/typec/ucsi/ucsi.c | 790 |
1 files changed, 790 insertions, 0 deletions
diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c new file mode 100644 index 000000000000..714c5bcedf2b --- /dev/null +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -0,0 +1,790 @@ +/* + * USB Type-C Connector System Software Interface driver + * + * Copyright (C) 2017, Intel Corporation + * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/completion.h> +#include <linux/property.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/usb/typec.h> + +#include "ucsi.h" +#include "trace.h" + +#define to_ucsi_connector(_cap_) container_of(_cap_, struct ucsi_connector, \ + typec_cap) + +/* + * UCSI_TIMEOUT_MS - PPM communication timeout + * + * Ideally we could use MIN_TIME_TO_RESPOND_WITH_BUSY (which is defined in UCSI + * specification) here as reference, but unfortunately we can't. It is very + * difficult to estimate the time it takes for the system to process the command + * before it is actually passed to the PPM. + */ +#define UCSI_TIMEOUT_MS 1000 + +/* + * UCSI_SWAP_TIMEOUT_MS - Timeout for role swap requests + * + * 5 seconds is close to the time it takes for CapsCounter to reach 0, so even + * if the PPM does not generate Connector Change events before that with + * partners that do not support USB Power Delivery, this should still work. + */ +#define UCSI_SWAP_TIMEOUT_MS 5000 + +enum ucsi_status { + UCSI_IDLE = 0, + UCSI_BUSY, + UCSI_ERROR, +}; + +struct ucsi_connector { + int num; + + struct ucsi *ucsi; + struct work_struct work; + struct completion complete; + + struct typec_port *port; + struct typec_partner *partner; + + struct typec_capability typec_cap; + + struct ucsi_connector_status status; + struct ucsi_connector_capability cap; +}; + +struct ucsi { + struct device *dev; + struct ucsi_ppm *ppm; + + enum ucsi_status status; + struct completion complete; + struct ucsi_capability cap; + struct ucsi_connector *connector; + + struct work_struct work; + + /* PPM Communication lock */ + struct mutex ppm_lock; + + /* PPM communication flags */ + unsigned long flags; +#define EVENT_PENDING 0 +#define COMMAND_PENDING 1 +#define ACK_PENDING 2 +}; + +static inline int ucsi_sync(struct ucsi *ucsi) +{ + if (ucsi->ppm && ucsi->ppm->sync) + return ucsi->ppm->sync(ucsi->ppm); + return 0; +} + +static int ucsi_command(struct ucsi *ucsi, struct ucsi_control *ctrl) +{ + int ret; + + trace_ucsi_command(ctrl); + + set_bit(COMMAND_PENDING, &ucsi->flags); + + ret = ucsi->ppm->cmd(ucsi->ppm, ctrl); + if (ret) + goto err_clear_flag; + + if (!wait_for_completion_timeout(&ucsi->complete, + msecs_to_jiffies(UCSI_TIMEOUT_MS))) { + dev_warn(ucsi->dev, "PPM NOT RESPONDING\n"); + ret = -ETIMEDOUT; + } + +err_clear_flag: + clear_bit(COMMAND_PENDING, &ucsi->flags); + + return ret; +} + +static int ucsi_ack(struct ucsi *ucsi, u8 ack) +{ + struct ucsi_control ctrl; + int ret; + + trace_ucsi_ack(ack); + + set_bit(ACK_PENDING, &ucsi->flags); + + UCSI_CMD_ACK(ctrl, ack); + ret = ucsi->ppm->cmd(ucsi->ppm, &ctrl); + if (ret) + goto out_clear_bit; + + /* Waiting for ACK with ACK CMD, but not with EVENT for now */ + if (ack == UCSI_ACK_EVENT) + goto out_clear_bit; + + if (!wait_for_completion_timeout(&ucsi->complete, + msecs_to_jiffies(UCSI_TIMEOUT_MS))) + ret = -ETIMEDOUT; + +out_clear_bit: + clear_bit(ACK_PENDING, &ucsi->flags); + + if (ret) + dev_err(ucsi->dev, "%s: failed\n", __func__); + + return ret; +} + +static int ucsi_run_command(struct ucsi *ucsi, struct ucsi_control *ctrl, + void *data, size_t size) +{ + struct ucsi_control _ctrl; + u8 data_length; + u16 error; + int ret; + + ret = ucsi_command(ucsi, ctrl); + if (ret) + goto err; + + switch (ucsi->status) { + case UCSI_IDLE: + ret = ucsi_sync(ucsi); + if (ret) + dev_warn(ucsi->dev, "%s: sync failed\n", __func__); + + if (data) + memcpy(data, ucsi->ppm->data->message_in, size); + + data_length = ucsi->ppm->data->cci.data_length; + + ret = ucsi_ack(ucsi, UCSI_ACK_CMD); + if (!ret) + ret = data_length; + break; + case UCSI_BUSY: + /* The caller decides whether to cancel or not */ + ret = -EBUSY; + break; + case UCSI_ERROR: + ret = ucsi_ack(ucsi, UCSI_ACK_CMD); + if (ret) + break; + + _ctrl.raw_cmd = 0; + _ctrl.cmd.cmd = UCSI_GET_ERROR_STATUS; + ret = ucsi_command(ucsi, &_ctrl); + if (ret) { + dev_err(ucsi->dev, "reading error failed!\n"); + break; + } + + memcpy(&error, ucsi->ppm->data->message_in, sizeof(error)); + + /* Something has really gone wrong */ + if (WARN_ON(ucsi->status == UCSI_ERROR)) { + ret = -ENODEV; + break; + } + + ret = ucsi_ack(ucsi, UCSI_ACK_CMD); + if (ret) + break; + + switch (error) { + case UCSI_ERROR_INCOMPATIBLE_PARTNER: + ret = -EOPNOTSUPP; + break; + case UCSI_ERROR_CC_COMMUNICATION_ERR: + ret = -ECOMM; + break; + case UCSI_ERROR_CONTRACT_NEGOTIATION_FAIL: + ret = -EPROTO; + break; + case UCSI_ERROR_DEAD_BATTERY: + dev_warn(ucsi->dev, "Dead battery condition!\n"); + ret = -EPERM; + break; + /* The following mean a bug in this driver */ + case UCSI_ERROR_INVALID_CON_NUM: + case UCSI_ERROR_UNREGONIZED_CMD: + case UCSI_ERROR_INVALID_CMD_ARGUMENT: + dev_warn(ucsi->dev, + "%s: possible UCSI driver bug - error 0x%x\n", + __func__, error); + ret = -EINVAL; + break; + default: + dev_warn(ucsi->dev, + "%s: error without status\n", __func__); + ret = -EIO; + break; + } + break; + } + +err: + trace_ucsi_run_command(ctrl, ret); + + return ret; +} + +/* -------------------------------------------------------------------------- */ + +static void ucsi_pwr_opmode_change(struct ucsi_connector *con) +{ + switch (con->status.pwr_op_mode) { + case UCSI_CONSTAT_PWR_OPMODE_PD: + typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_PD); + break; + case UCSI_CONSTAT_PWR_OPMODE_TYPEC1_5: + typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_1_5A); + break; + case UCSI_CONSTAT_PWR_OPMODE_TYPEC3_0: + typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_3_0A); + break; + default: + typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_USB); + break; + } +} + +static int ucsi_register_partner(struct ucsi_connector *con) +{ + struct typec_partner_desc partner; + + if (con->partner) + return 0; + + memset(&partner, 0, sizeof(partner)); + + switch (con->status.partner_type) { + case UCSI_CONSTAT_PARTNER_TYPE_DEBUG: + partner.accessory = TYPEC_ACCESSORY_DEBUG; + break; + case UCSI_CONSTAT_PARTNER_TYPE_AUDIO: + partner.accessory = TYPEC_ACCESSORY_AUDIO; + break; + default: + break; + } + + partner.usb_pd = con->status.pwr_op_mode == UCSI_CONSTAT_PWR_OPMODE_PD; + + con->partner = typec_register_partner(con->port, &partner); + if (!con->partner) { + dev_err(con->ucsi->dev, "con%d: failed to register partner\n", + con->num); + return -ENODEV; + } + + return 0; +} + +static void ucsi_unregister_partner(struct ucsi_connector *con) +{ + typec_unregister_partner(con->partner); + con->partner = NULL; +} + +static void ucsi_connector_change(struct work_struct *work) +{ + struct ucsi_connector *con = container_of(work, struct ucsi_connector, + work); + struct ucsi *ucsi = con->ucsi; + struct ucsi_control ctrl; + int ret; + + mutex_lock(&ucsi->ppm_lock); + + UCSI_CMD_GET_CONNECTOR_STATUS(ctrl, con->num); + ret = ucsi_run_command(ucsi, &ctrl, &con->status, sizeof(con->status)); + if (ret < 0) { + dev_err(ucsi->dev, "%s: GET_CONNECTOR_STATUS failed (%d)\n", + __func__, ret); + goto out_unlock; + } + + if (con->status.change & UCSI_CONSTAT_POWER_OPMODE_CHANGE) + ucsi_pwr_opmode_change(con); + + if (con->status.change & UCSI_CONSTAT_POWER_DIR_CHANGE) { + typec_set_pwr_role(con->port, con->status.pwr_dir); + + /* Complete pending power role swap */ + if (!completion_done(&con->complete)) + complete(&con->complete); + } + + if (con->status.change & UCSI_CONSTAT_PARTNER_CHANGE) { + switch (con->status.partner_type) { + case UCSI_CONSTAT_PARTNER_TYPE_UFP: + typec_set_data_role(con->port, TYPEC_HOST); + break; + case UCSI_CONSTAT_PARTNER_TYPE_DFP: + typec_set_data_role(con->port, TYPEC_DEVICE); + break; + default: + break; + } + + /* Complete pending data role swap */ + if (!completion_done(&con->complete)) + complete(&con->complete); + } + + if (con->status.change & UCSI_CONSTAT_CONNECT_CHANGE) { + if (con->status.connected) + ucsi_register_partner(con); + else + ucsi_unregister_partner(con); + } + + ret = ucsi_ack(ucsi, UCSI_ACK_EVENT); + if (ret) + dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret); + + trace_ucsi_connector_change(con->num, &con->status); + +out_unlock: + clear_bit(EVENT_PENDING, &ucsi->flags); + mutex_unlock(&ucsi->ppm_lock); +} + +/** + * ucsi_notify - PPM notification handler + * @ucsi: Source UCSI Interface for the notifications + * + * Handle notifications from PPM of @ucsi. + */ +void ucsi_notify(struct ucsi *ucsi) +{ + struct ucsi_cci *cci; + + /* There is no requirement to sync here, but no harm either. */ + ucsi_sync(ucsi); + + cci = &ucsi->ppm->data->cci; + + if (cci->error) + ucsi->status = UCSI_ERROR; + else if (cci->busy) + ucsi->status = UCSI_BUSY; + else + ucsi->status = UCSI_IDLE; + + if (cci->cmd_complete && test_bit(COMMAND_PENDING, &ucsi->flags)) { + complete(&ucsi->complete); + } else if (cci->ack_complete && test_bit(ACK_PENDING, &ucsi->flags)) { + complete(&ucsi->complete); + } else if (cci->connector_change) { + struct ucsi_connector *con; + + con = &ucsi->connector[cci->connector_change - 1]; + + if (!test_and_set_bit(EVENT_PENDING, &ucsi->flags)) + schedule_work(&con->work); + } + + trace_ucsi_notify(ucsi->ppm->data->raw_cci); +} +EXPORT_SYMBOL_GPL(ucsi_notify); + +/* -------------------------------------------------------------------------- */ + +static int ucsi_reset_connector(struct ucsi_connector *con, bool hard) +{ + struct ucsi_control ctrl; + + UCSI_CMD_CONNECTOR_RESET(ctrl, con, hard); + + return ucsi_run_command(con->ucsi, &ctrl, NULL, 0); +} + +static int ucsi_reset_ppm(struct ucsi *ucsi) +{ + struct ucsi_control ctrl; + unsigned long tmo; + int ret; + + ctrl.raw_cmd = 0; + ctrl.cmd.cmd = UCSI_PPM_RESET; + trace_ucsi_command(&ctrl); + ret = ucsi->ppm->cmd(ucsi->ppm, &ctrl); + if (ret) + goto err; + + tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS); + + do { + /* Here sync is critical. */ + ret = ucsi_sync(ucsi); + if (ret) + goto err; + + if (ucsi->ppm->data->cci.reset_complete) + break; + + /* If the PPM is still doing something else, reset it again. */ + if (ucsi->ppm->data->raw_cci) { + dev_warn_ratelimited(ucsi->dev, + "Failed to reset PPM! Trying again..\n"); + + trace_ucsi_command(&ctrl); + ret = ucsi->ppm->cmd(ucsi->ppm, &ctrl); + if (ret) + goto err; + } + + /* Letting the PPM settle down. */ + msleep(20); + + ret = -ETIMEDOUT; + } while (time_is_after_jiffies(tmo)); + +err: + trace_ucsi_reset_ppm(&ctrl, ret); + + return ret; +} + +static int ucsi_role_cmd(struct ucsi_connector *con, struct ucsi_control *ctrl) +{ + int ret; + + ret = ucsi_run_command(con->ucsi, ctrl, NULL, 0); + if (ret == -ETIMEDOUT) { + struct ucsi_control c; + + /* PPM most likely stopped responding. Resetting everything. */ + ucsi_reset_ppm(con->ucsi); + + UCSI_CMD_SET_NTFY_ENABLE(c, UCSI_ENABLE_NTFY_ALL); + ucsi_run_command(con->ucsi, &c, NULL, 0); + + ucsi_reset_connector(con, true); + } + + return ret; +} + +static int +ucsi_dr_swap(const struct typec_capability *cap, enum typec_data_role role) +{ + struct ucsi_connector *con = to_ucsi_connector(cap); + struct ucsi_control ctrl; + int ret = 0; + + if (!con->partner) + return -ENOTCONN; + + mutex_lock(&con->ucsi->ppm_lock); + + if ((con->status.partner_type == UCSI_CONSTAT_PARTNER_TYPE_DFP && + role == TYPEC_DEVICE) || + (con->status.partner_type == UCSI_CONSTAT_PARTNER_TYPE_UFP && + role == TYPEC_HOST)) + goto out_unlock; + + UCSI_CMD_SET_UOR(ctrl, con, role); + ret = ucsi_role_cmd(con, &ctrl); + if (ret < 0) + goto out_unlock; + + mutex_unlock(&con->ucsi->ppm_lock); + + if (!wait_for_completion_timeout(&con->complete, + msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS))) + return -ETIMEDOUT; + + return 0; + +out_unlock: + mutex_unlock(&con->ucsi->ppm_lock); + + return ret; +} + +static int +ucsi_pr_swap(const struct typec_capability *cap, enum typec_role role) +{ + struct ucsi_connector *con = to_ucsi_connector(cap); + struct ucsi_control ctrl; + int ret = 0; + + if (!con->partner) + return -ENOTCONN; + + mutex_lock(&con->ucsi->ppm_lock); + + if (con->status.pwr_dir == role) + goto out_unlock; + + UCSI_CMD_SET_PDR(ctrl, con, role); + ret = ucsi_role_cmd(con, &ctrl); + if (ret < 0) + goto out_unlock; + + mutex_unlock(&con->ucsi->ppm_lock); + + if (!wait_for_completion_timeout(&con->complete, + msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS))) + return -ETIMEDOUT; + + mutex_lock(&con->ucsi->ppm_lock); + + /* Something has gone wrong while swapping the role */ + if (con->status.pwr_op_mode != UCSI_CONSTAT_PWR_OPMODE_PD) { + ucsi_reset_connector(con, true); + ret = -EPROTO; + } + +out_unlock: + mutex_unlock(&con->ucsi->ppm_lock); + + return ret; +} + +static struct fwnode_handle *ucsi_find_fwnode(struct ucsi_connector *con) +{ + struct fwnode_handle *fwnode; + int i = 1; + + device_for_each_child_node(con->ucsi->dev, fwnode) + if (i++ == con->num) + return fwnode; + return NULL; +} + +static int ucsi_register_port(struct ucsi *ucsi, int index) +{ + struct ucsi_connector *con = &ucsi->connector[index]; + struct typec_capability *cap = &con->typec_cap; + enum typec_accessory *accessory = cap->accessory; + struct ucsi_control ctrl; + int ret; + + INIT_WORK(&con->work, ucsi_connector_change); + init_completion(&con->complete); + con->num = index + 1; + con->ucsi = ucsi; + + /* Get connector capability */ + UCSI_CMD_GET_CONNECTOR_CAPABILITY(ctrl, con->num); + ret = ucsi_run_command(ucsi, &ctrl, &con->cap, sizeof(con->cap)); + if (ret < 0) + return ret; + + if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DRP) + cap->type = TYPEC_PORT_DRP; + else if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DFP) + cap->type = TYPEC_PORT_DFP; + else if (con->cap.op_mode & UCSI_CONCAP_OPMODE_UFP) + cap->type = TYPEC_PORT_UFP; + + cap->revision = ucsi->cap.typec_version; + cap->pd_revision = ucsi->cap.pd_version; + cap->prefer_role = TYPEC_NO_PREFERRED_ROLE; + + if (con->cap.op_mode & UCSI_CONCAP_OPMODE_AUDIO_ACCESSORY) + *accessory++ = TYPEC_ACCESSORY_AUDIO; + if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DEBUG_ACCESSORY) + *accessory = TYPEC_ACCESSORY_DEBUG; + + cap->fwnode = ucsi_find_fwnode(con); + cap->dr_set = ucsi_dr_swap; + cap->pr_set = ucsi_pr_swap; + + /* Register the connector */ + con->port = typec_register_port(ucsi->dev, cap); + if (!con->port) + return -ENODEV; + + /* Get the status */ + UCSI_CMD_GET_CONNECTOR_STATUS(ctrl, con->num); + ret = ucsi_run_command(ucsi, &ctrl, &con->status, sizeof(con->status)); + if (ret < 0) { + dev_err(ucsi->dev, "con%d: failed to get status\n", con->num); + return 0; + } + + ucsi_pwr_opmode_change(con); + typec_set_pwr_role(con->port, con->status.pwr_dir); + + switch (con->status.partner_type) { + case UCSI_CONSTAT_PARTNER_TYPE_UFP: + typec_set_data_role(con->port, TYPEC_HOST); + break; + case UCSI_CONSTAT_PARTNER_TYPE_DFP: + typec_set_data_role(con->port, TYPEC_DEVICE); + break; + default: + break; + } + + /* Check if there is already something connected */ + if (con->status.connected) + ucsi_register_partner(con); + + trace_ucsi_register_port(con->num, &con->status); + + return 0; +} + +static void ucsi_init(struct work_struct *work) +{ + struct ucsi *ucsi = container_of(work, struct ucsi, work); + struct ucsi_connector *con; + struct ucsi_control ctrl; + int ret; + int i; + + mutex_lock(&ucsi->ppm_lock); + + /* Reset the PPM */ + ret = ucsi_reset_ppm(ucsi); + if (ret) { + dev_err(ucsi->dev, "failed to reset PPM!\n"); + goto err; + } + + /* Enable basic notifications */ + UCSI_CMD_SET_NTFY_ENABLE(ctrl, UCSI_ENABLE_NTFY_CMD_COMPLETE | + UCSI_ENABLE_NTFY_ERROR); + ret = ucsi_run_command(ucsi, &ctrl, NULL, 0); + if (ret < 0) + goto err_reset; + + /* Get PPM capabilities */ + UCSI_CMD_GET_CAPABILITY(ctrl); + ret = ucsi_run_command(ucsi, &ctrl, &ucsi->cap, sizeof(ucsi->cap)); + if (ret < 0) + goto err_reset; + + if (!ucsi->cap.num_connectors) { + ret = -ENODEV; + goto err_reset; + } + + /* Allocate the connectors. Released in ucsi_unregister_ppm() */ + ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1, + sizeof(*ucsi->connector), GFP_KERNEL); + if (!ucsi->connector) { + ret = -ENOMEM; + goto err_reset; + } + + /* Register all connectors */ + for (i = 0; i < ucsi->cap.num_connectors; i++) { + ret = ucsi_register_port(ucsi, i); + if (ret) + goto err_unregister; + } + + /* Enable all notifications */ + UCSI_CMD_SET_NTFY_ENABLE(ctrl, UCSI_ENABLE_NTFY_ALL); + ret = ucsi_run_command(ucsi, &ctrl, NULL, 0); + if (ret < 0) + goto err_unregister; + + mutex_unlock(&ucsi->ppm_lock); + + return; + +err_unregister: + for (con = ucsi->connector; con->port; con++) { + ucsi_unregister_partner(con); + typec_unregister_port(con->port); + con->port = NULL; + } + +err_reset: + ucsi_reset_ppm(ucsi); +err: + mutex_unlock(&ucsi->ppm_lock); + dev_err(ucsi->dev, "PPM init failed (%d)\n", ret); +} + +/** + * ucsi_register_ppm - Register UCSI PPM Interface + * @dev: Device interface to the PPM + * @ppm: The PPM interface + * + * Allocates UCSI instance, associates it with @ppm and returns it to the + * caller, and schedules initialization of the interface. + */ +struct ucsi *ucsi_register_ppm(struct device *dev, struct ucsi_ppm *ppm) +{ + struct ucsi *ucsi; + + ucsi = kzalloc(sizeof(*ucsi), GFP_KERNEL); + if (!ucsi) + return ERR_PTR(-ENOMEM); + + INIT_WORK(&ucsi->work, ucsi_init); + init_completion(&ucsi->complete); + mutex_init(&ucsi->ppm_lock); + + ucsi->dev = dev; + ucsi->ppm = ppm; + + /* + * Communication with the PPM takes a lot of time. It is not reasonable + * to initialize the driver here. Using a work for now. + */ + queue_work(system_long_wq, &ucsi->work); + + return ucsi; +} +EXPORT_SYMBOL_GPL(ucsi_register_ppm); + +/** + * ucsi_unregister_ppm - Unregister UCSI PPM Interface + * @ucsi: struct ucsi associated with the PPM + * + * Unregister UCSI PPM that was created with ucsi_register(). + */ +void ucsi_unregister_ppm(struct ucsi *ucsi) +{ + struct ucsi_control ctrl; + int i; + + /* Make sure that we are not in the middle of driver initialization */ + cancel_work_sync(&ucsi->work); + + mutex_lock(&ucsi->ppm_lock); + + /* Disable everything except command complete notification */ + UCSI_CMD_SET_NTFY_ENABLE(ctrl, UCSI_ENABLE_NTFY_CMD_COMPLETE) + ucsi_run_command(ucsi, &ctrl, NULL, 0); + + mutex_unlock(&ucsi->ppm_lock); + + for (i = 0; i < ucsi->cap.num_connectors; i++) { + cancel_work_sync(&ucsi->connector[i].work); + ucsi_unregister_partner(&ucsi->connector[i]); + typec_unregister_port(ucsi->connector[i].port); + } + + ucsi_reset_ppm(ucsi); + + kfree(ucsi->connector); + kfree(ucsi); +} +EXPORT_SYMBOL_GPL(ucsi_unregister_ppm); + +MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("USB Type-C Connector System Software Interface driver"); |