diff options
Diffstat (limited to 'drivers/extcon/extcon-usbc-cros-ec.c')
-rw-r--r-- | drivers/extcon/extcon-usbc-cros-ec.c | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/drivers/extcon/extcon-usbc-cros-ec.c b/drivers/extcon/extcon-usbc-cros-ec.c new file mode 100644 index 000000000..fde1db62b --- /dev/null +++ b/drivers/extcon/extcon-usbc-cros-ec.c @@ -0,0 +1,542 @@ +// SPDX-License-Identifier: GPL-2.0 +// ChromeOS Embedded Controller extcon +// +// Copyright (C) 2017 Google, Inc. +// Author: Benson Leung <bleung@chromium.org> + +#include <linux/extcon-provider.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/notifier.h> +#include <linux/of.h> +#include <linux/platform_data/cros_ec_commands.h> +#include <linux/platform_data/cros_ec_proto.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/sched.h> + +struct cros_ec_extcon_info { + struct device *dev; + struct extcon_dev *edev; + + int port_id; + + struct cros_ec_device *ec; + + struct notifier_block notifier; + + unsigned int dr; /* data role */ + bool pr; /* power role (true if VBUS enabled) */ + bool dp; /* DisplayPort enabled */ + bool mux; /* SuperSpeed (usb3) enabled */ + unsigned int power_type; +}; + +static const unsigned int usb_type_c_cable[] = { + EXTCON_USB, + EXTCON_USB_HOST, + EXTCON_DISP_DP, + EXTCON_NONE, +}; + +enum usb_data_roles { + DR_NONE, + DR_HOST, + DR_DEVICE, +}; + +/** + * cros_ec_pd_command() - Send a command to the EC. + * @info: pointer to struct cros_ec_extcon_info + * @command: EC command + * @version: EC command version + * @outdata: EC command output data + * @outsize: Size of outdata + * @indata: EC command input data + * @insize: Size of indata + * + * Return: 0 on success, <0 on failure. + */ +static int cros_ec_pd_command(struct cros_ec_extcon_info *info, + unsigned int command, + unsigned int version, + void *outdata, + unsigned int outsize, + void *indata, + unsigned int insize) +{ + struct cros_ec_command *msg; + int ret; + + msg = kzalloc(struct_size(msg, data, max(outsize, insize)), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + msg->version = version; + msg->command = command; + msg->outsize = outsize; + msg->insize = insize; + + if (outsize) + memcpy(msg->data, outdata, outsize); + + ret = cros_ec_cmd_xfer_status(info->ec, msg); + if (ret >= 0 && insize) + memcpy(indata, msg->data, insize); + + kfree(msg); + return ret; +} + +/** + * cros_ec_usb_get_power_type() - Get power type info about PD device attached + * to given port. + * @info: pointer to struct cros_ec_extcon_info + * + * Return: power type on success, <0 on failure. + */ +static int cros_ec_usb_get_power_type(struct cros_ec_extcon_info *info) +{ + struct ec_params_usb_pd_power_info req; + struct ec_response_usb_pd_power_info resp; + int ret; + + req.port = info->port_id; + ret = cros_ec_pd_command(info, EC_CMD_USB_PD_POWER_INFO, 0, + &req, sizeof(req), &resp, sizeof(resp)); + if (ret < 0) + return ret; + + return resp.type; +} + +/** + * cros_ec_usb_get_pd_mux_state() - Get PD mux state for given port. + * @info: pointer to struct cros_ec_extcon_info + * + * Return: PD mux state on success, <0 on failure. + */ +static int cros_ec_usb_get_pd_mux_state(struct cros_ec_extcon_info *info) +{ + struct ec_params_usb_pd_mux_info req; + struct ec_response_usb_pd_mux_info resp; + int ret; + + req.port = info->port_id; + ret = cros_ec_pd_command(info, EC_CMD_USB_PD_MUX_INFO, 0, + &req, sizeof(req), + &resp, sizeof(resp)); + if (ret < 0) + return ret; + + return resp.flags; +} + +/** + * cros_ec_usb_get_role() - Get role info about possible PD device attached to a + * given port. + * @info: pointer to struct cros_ec_extcon_info + * @polarity: pointer to cable polarity (return value) + * + * Return: role info on success, -ENOTCONN if no cable is connected, <0 on + * failure. + */ +static int cros_ec_usb_get_role(struct cros_ec_extcon_info *info, + bool *polarity) +{ + struct ec_params_usb_pd_control pd_control; + struct ec_response_usb_pd_control_v1 resp; + int ret; + + pd_control.port = info->port_id; + pd_control.role = USB_PD_CTRL_ROLE_NO_CHANGE; + pd_control.mux = USB_PD_CTRL_MUX_NO_CHANGE; + pd_control.swap = USB_PD_CTRL_SWAP_NONE; + ret = cros_ec_pd_command(info, EC_CMD_USB_PD_CONTROL, 1, + &pd_control, sizeof(pd_control), + &resp, sizeof(resp)); + if (ret < 0) + return ret; + + if (!(resp.enabled & PD_CTRL_RESP_ENABLED_CONNECTED)) + return -ENOTCONN; + + *polarity = resp.polarity; + + return resp.role; +} + +/** + * cros_ec_pd_get_num_ports() - Get number of EC charge ports. + * @info: pointer to struct cros_ec_extcon_info + * + * Return: number of ports on success, <0 on failure. + */ +static int cros_ec_pd_get_num_ports(struct cros_ec_extcon_info *info) +{ + struct ec_response_usb_pd_ports resp; + int ret; + + ret = cros_ec_pd_command(info, EC_CMD_USB_PD_PORTS, + 0, NULL, 0, &resp, sizeof(resp)); + if (ret < 0) + return ret; + + return resp.num_ports; +} + +static const char *cros_ec_usb_role_string(unsigned int role) +{ + return role == DR_NONE ? "DISCONNECTED" : + (role == DR_HOST ? "DFP" : "UFP"); +} + +static const char *cros_ec_usb_power_type_string(unsigned int type) +{ + switch (type) { + case USB_CHG_TYPE_NONE: + return "USB_CHG_TYPE_NONE"; + case USB_CHG_TYPE_PD: + return "USB_CHG_TYPE_PD"; + case USB_CHG_TYPE_PROPRIETARY: + return "USB_CHG_TYPE_PROPRIETARY"; + case USB_CHG_TYPE_C: + return "USB_CHG_TYPE_C"; + case USB_CHG_TYPE_BC12_DCP: + return "USB_CHG_TYPE_BC12_DCP"; + case USB_CHG_TYPE_BC12_CDP: + return "USB_CHG_TYPE_BC12_CDP"; + case USB_CHG_TYPE_BC12_SDP: + return "USB_CHG_TYPE_BC12_SDP"; + case USB_CHG_TYPE_OTHER: + return "USB_CHG_TYPE_OTHER"; + case USB_CHG_TYPE_VBUS: + return "USB_CHG_TYPE_VBUS"; + case USB_CHG_TYPE_UNKNOWN: + return "USB_CHG_TYPE_UNKNOWN"; + default: + return "USB_CHG_TYPE_UNKNOWN"; + } +} + +static bool cros_ec_usb_power_type_is_wall_wart(unsigned int type, + unsigned int role) +{ + switch (type) { + /* FIXME : Guppy, Donnettes, and other chargers will be miscategorized + * because they identify with USB_CHG_TYPE_C, but we can't return true + * here from that code because that breaks Suzy-Q and other kinds of + * USB Type-C cables and peripherals. + */ + case USB_CHG_TYPE_PROPRIETARY: + case USB_CHG_TYPE_BC12_DCP: + return true; + case USB_CHG_TYPE_PD: + case USB_CHG_TYPE_C: + case USB_CHG_TYPE_BC12_CDP: + case USB_CHG_TYPE_BC12_SDP: + case USB_CHG_TYPE_OTHER: + case USB_CHG_TYPE_VBUS: + case USB_CHG_TYPE_UNKNOWN: + case USB_CHG_TYPE_NONE: + default: + return false; + } +} + +static int extcon_cros_ec_detect_cable(struct cros_ec_extcon_info *info, + bool force) +{ + struct device *dev = info->dev; + int role, power_type; + unsigned int dr = DR_NONE; + bool pr = false; + bool polarity = false; + bool dp = false; + bool mux = false; + bool hpd = false; + + power_type = cros_ec_usb_get_power_type(info); + if (power_type < 0) { + dev_err(dev, "failed getting power type err = %d\n", + power_type); + return power_type; + } + + role = cros_ec_usb_get_role(info, &polarity); + if (role < 0) { + if (role != -ENOTCONN) { + dev_err(dev, "failed getting role err = %d\n", role); + return role; + } + dev_dbg(dev, "disconnected\n"); + } else { + int pd_mux_state; + + dr = (role & PD_CTRL_RESP_ROLE_DATA) ? DR_HOST : DR_DEVICE; + pr = (role & PD_CTRL_RESP_ROLE_POWER); + pd_mux_state = cros_ec_usb_get_pd_mux_state(info); + if (pd_mux_state < 0) + pd_mux_state = USB_PD_MUX_USB_ENABLED; + + dp = pd_mux_state & USB_PD_MUX_DP_ENABLED; + mux = pd_mux_state & USB_PD_MUX_USB_ENABLED; + hpd = pd_mux_state & USB_PD_MUX_HPD_IRQ; + + dev_dbg(dev, + "connected role 0x%x pwr type %d dr %d pr %d pol %d mux %d dp %d hpd %d\n", + role, power_type, dr, pr, polarity, mux, dp, hpd); + } + + /* + * When there is no USB host (e.g. USB PD charger), + * we are not really a UFP for the AP. + */ + if (dr == DR_DEVICE && + cros_ec_usb_power_type_is_wall_wart(power_type, role)) + dr = DR_NONE; + + if (force || info->dr != dr || info->pr != pr || info->dp != dp || + info->mux != mux || info->power_type != power_type) { + bool host_connected = false, device_connected = false; + + dev_dbg(dev, "Type/Role switch! type = %s role = %s\n", + cros_ec_usb_power_type_string(power_type), + cros_ec_usb_role_string(dr)); + info->dr = dr; + info->pr = pr; + info->dp = dp; + info->mux = mux; + info->power_type = power_type; + + if (dr == DR_DEVICE) + device_connected = true; + else if (dr == DR_HOST) + host_connected = true; + + extcon_set_state(info->edev, EXTCON_USB, device_connected); + extcon_set_state(info->edev, EXTCON_USB_HOST, host_connected); + extcon_set_state(info->edev, EXTCON_DISP_DP, dp); + extcon_set_property(info->edev, EXTCON_USB, + EXTCON_PROP_USB_VBUS, + (union extcon_property_value)(int)pr); + extcon_set_property(info->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_VBUS, + (union extcon_property_value)(int)pr); + extcon_set_property(info->edev, EXTCON_USB, + EXTCON_PROP_USB_TYPEC_POLARITY, + (union extcon_property_value)(int)polarity); + extcon_set_property(info->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_TYPEC_POLARITY, + (union extcon_property_value)(int)polarity); + extcon_set_property(info->edev, EXTCON_DISP_DP, + EXTCON_PROP_USB_TYPEC_POLARITY, + (union extcon_property_value)(int)polarity); + extcon_set_property(info->edev, EXTCON_USB, + EXTCON_PROP_USB_SS, + (union extcon_property_value)(int)mux); + extcon_set_property(info->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_SS, + (union extcon_property_value)(int)mux); + extcon_set_property(info->edev, EXTCON_DISP_DP, + EXTCON_PROP_USB_SS, + (union extcon_property_value)(int)mux); + extcon_set_property(info->edev, EXTCON_DISP_DP, + EXTCON_PROP_DISP_HPD, + (union extcon_property_value)(int)hpd); + + extcon_sync(info->edev, EXTCON_USB); + extcon_sync(info->edev, EXTCON_USB_HOST); + extcon_sync(info->edev, EXTCON_DISP_DP); + + } else if (hpd) { + extcon_set_property(info->edev, EXTCON_DISP_DP, + EXTCON_PROP_DISP_HPD, + (union extcon_property_value)(int)hpd); + extcon_sync(info->edev, EXTCON_DISP_DP); + } + + return 0; +} + +static int extcon_cros_ec_event(struct notifier_block *nb, + unsigned long queued_during_suspend, + void *_notify) +{ + struct cros_ec_extcon_info *info; + struct cros_ec_device *ec; + u32 host_event; + + info = container_of(nb, struct cros_ec_extcon_info, notifier); + ec = info->ec; + + host_event = cros_ec_get_host_event(ec); + if (host_event & (EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU) | + EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_MUX))) { + extcon_cros_ec_detect_cable(info, false); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static int extcon_cros_ec_probe(struct platform_device *pdev) +{ + struct cros_ec_extcon_info *info; + struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + int numports, ret; + + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->dev = dev; + info->ec = ec; + + if (np) { + u32 port; + + ret = of_property_read_u32(np, "google,usb-port-id", &port); + if (ret < 0) { + dev_err(dev, "Missing google,usb-port-id property\n"); + return ret; + } + info->port_id = port; + } else { + info->port_id = pdev->id; + } + + numports = cros_ec_pd_get_num_ports(info); + if (numports < 0) { + dev_err(dev, "failed getting number of ports! ret = %d\n", + numports); + return numports; + } + + if (info->port_id >= numports) { + dev_err(dev, "This system only supports %d ports\n", numports); + return -ENODEV; + } + + info->edev = devm_extcon_dev_allocate(dev, usb_type_c_cable); + if (IS_ERR(info->edev)) { + dev_err(dev, "failed to allocate extcon device\n"); + return -ENOMEM; + } + + ret = devm_extcon_dev_register(dev, info->edev); + if (ret < 0) { + dev_err(dev, "failed to register extcon device\n"); + return ret; + } + + extcon_set_property_capability(info->edev, EXTCON_USB, + EXTCON_PROP_USB_VBUS); + extcon_set_property_capability(info->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_VBUS); + extcon_set_property_capability(info->edev, EXTCON_USB, + EXTCON_PROP_USB_TYPEC_POLARITY); + extcon_set_property_capability(info->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_TYPEC_POLARITY); + extcon_set_property_capability(info->edev, EXTCON_DISP_DP, + EXTCON_PROP_USB_TYPEC_POLARITY); + extcon_set_property_capability(info->edev, EXTCON_USB, + EXTCON_PROP_USB_SS); + extcon_set_property_capability(info->edev, EXTCON_USB_HOST, + EXTCON_PROP_USB_SS); + extcon_set_property_capability(info->edev, EXTCON_DISP_DP, + EXTCON_PROP_USB_SS); + extcon_set_property_capability(info->edev, EXTCON_DISP_DP, + EXTCON_PROP_DISP_HPD); + + info->dr = DR_NONE; + info->pr = false; + + platform_set_drvdata(pdev, info); + + /* Get PD events from the EC */ + info->notifier.notifier_call = extcon_cros_ec_event; + ret = blocking_notifier_chain_register(&info->ec->event_notifier, + &info->notifier); + if (ret < 0) { + dev_err(dev, "failed to register notifier\n"); + return ret; + } + + /* Perform initial detection */ + ret = extcon_cros_ec_detect_cable(info, true); + if (ret < 0) { + dev_err(dev, "failed to detect initial cable state\n"); + goto unregister_notifier; + } + + return 0; + +unregister_notifier: + blocking_notifier_chain_unregister(&info->ec->event_notifier, + &info->notifier); + return ret; +} + +static int extcon_cros_ec_remove(struct platform_device *pdev) +{ + struct cros_ec_extcon_info *info = platform_get_drvdata(pdev); + + blocking_notifier_chain_unregister(&info->ec->event_notifier, + &info->notifier); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int extcon_cros_ec_suspend(struct device *dev) +{ + return 0; +} + +static int extcon_cros_ec_resume(struct device *dev) +{ + int ret; + struct cros_ec_extcon_info *info = dev_get_drvdata(dev); + + ret = extcon_cros_ec_detect_cable(info, true); + if (ret < 0) + dev_err(dev, "failed to detect cable state on resume\n"); + + return 0; +} + +static const struct dev_pm_ops extcon_cros_ec_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(extcon_cros_ec_suspend, extcon_cros_ec_resume) +}; + +#define DEV_PM_OPS (&extcon_cros_ec_dev_pm_ops) +#else +#define DEV_PM_OPS NULL +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_OF +static const struct of_device_id extcon_cros_ec_of_match[] = { + { .compatible = "google,extcon-usbc-cros-ec" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, extcon_cros_ec_of_match); +#endif /* CONFIG_OF */ + +static struct platform_driver extcon_cros_ec_driver = { + .driver = { + .name = "extcon-usbc-cros-ec", + .of_match_table = of_match_ptr(extcon_cros_ec_of_match), + .pm = DEV_PM_OPS, + }, + .remove = extcon_cros_ec_remove, + .probe = extcon_cros_ec_probe, +}; + +module_platform_driver(extcon_cros_ec_driver); + +MODULE_DESCRIPTION("ChromeOS Embedded Controller extcon driver"); +MODULE_AUTHOR("Benson Leung <bleung@chromium.org>"); +MODULE_LICENSE("GPL v2"); |