lkml.org 
[lkml]   [2017]   [Jul]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v3.1 1/2] extcon: cros-ec: Add extcon-cros-ec driver to support display out.
Date
From: Benson Leung <bleung@chromium.org>

This is the driver for the USB Type C cable detection mechanism
built into the ChromeOS Embedded Controller on systems that
have USB Type-C ports.

At present, this allows for the presence of display out, but in
future, it may also be used to notify host and device type cables
and the presence of power.

Signed-off-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Chanwoo Choi <cw00.chio@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
---
Changes since v3:
- Fix rebase.
Changes since v2:
- Rebase on top of v4.13-rc1
Changes since v1:
Requested by Chanwoo Choi
- Rename files changing _ for -
- Remove the unneeded blank line on bottom of header.
- Remove kobject.h and cros_ec_commands.h includes.
- Remove the debug message as is not necessary.
- Use the tab for indentation instead of space for if sentence.
- Define each variable on different lines when the variables should be
initialized.
- Remove EXTCON_USB and EXTCON_USB_HOST as are not really used for now.
- Add one blank line to split out between state and property setting.
- Add the author information (header and module)

Enric Balletbo
- As Rob suggested to rename the compatible name to something indicating that
is USB Type C related I also renamed the file names, extcon-cros-ec ->
extcon-usbc-cros-ec, I think it's more clear.

drivers/extcon/Kconfig | 7 +
drivers/extcon/Makefile | 1 +
drivers/extcon/extcon-usbc-cros-ec.c | 415 +++++++++++++++++++++++++++++++++++
include/linux/mfd/cros_ec_commands.h | 75 +++++++
4 files changed, 498 insertions(+)
create mode 100644 drivers/extcon/extcon-usbc-cros-ec.c

diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index 6d50071..a7bca42 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -150,4 +150,11 @@ config EXTCON_USB_GPIO
Say Y here to enable GPIO based USB cable detection extcon support.
Used typically if GPIO is used for USB ID pin detection.

+config EXTCON_USBC_CROS_EC
+ tristate "ChromeOS Embedded Controller EXTCON support"
+ depends on MFD_CROS_EC
+ help
+ Say Y here to enable USB Type C cable detection extcon support when
+ using Chrome OS EC based USB Type-C ports.
+
endif
diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
index ecfa958..a73624e 100644
--- a/drivers/extcon/Makefile
+++ b/drivers/extcon/Makefile
@@ -20,3 +20,4 @@ obj-$(CONFIG_EXTCON_QCOM_SPMI_MISC) += extcon-qcom-spmi-misc.o
obj-$(CONFIG_EXTCON_RT8973A) += extcon-rt8973a.o
obj-$(CONFIG_EXTCON_SM5502) += extcon-sm5502.o
obj-$(CONFIG_EXTCON_USB_GPIO) += extcon-usb-gpio.o
+obj-$(CONFIG_EXTCON_USBC_CROS_EC) += extcon-usbc-cros-ec.o
diff --git a/drivers/extcon/extcon-usbc-cros-ec.c b/drivers/extcon/extcon-usbc-cros-ec.c
new file mode 100644
index 0000000..e759ed4
--- /dev/null
+++ b/drivers/extcon/extcon-usbc-cros-ec.c
@@ -0,0 +1,415 @@
+/**
+ * drivers/extcon/extcon-usbc-cros-ec - ChromeOS Embedded Controller extcon
+ *
+ * Copyright (C) 2017 Google, Inc
+ * Author: Benson Leung <bleung@chromium.org>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#include <linux/extcon.h>
+#include <linux/kernel.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of.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;
+
+ bool dp; /* DisplayPort enabled */
+ bool mux; /* SuperSpeed (usb3) enabled */
+ unsigned int power_type;
+};
+
+static const unsigned int usb_type_c_cable[] = {
+ EXTCON_DISP_DP,
+ EXTCON_NONE,
+};
+
+/**
+ * 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(sizeof(*msg) + max(outsize, insize), GFP_KERNEL);
+
+ 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;
+ 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 int extcon_cros_ec_detect_cable(struct cros_ec_extcon_info *info,
+ bool force)
+{
+ struct device *dev = info->dev;
+ int role, power_type;
+ 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;
+ }
+ } else {
+ int pd_mux_state;
+
+ 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;
+ }
+
+ if (force || info->dp != dp || info->mux != mux ||
+ info->power_type != power_type) {
+
+ info->dp = dp;
+ info->mux = mux;
+ info->power_type = power_type;
+
+ extcon_set_state(info->edev, EXTCON_DISP_DP, dp);
+
+ 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_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_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_DISP_DP,
+ EXTCON_PROP_USB_TYPEC_POLARITY);
+ 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);
+
+ 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");
diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h
index 190c8f4..2b16e95 100644
--- a/include/linux/mfd/cros_ec_commands.h
+++ b/include/linux/mfd/cros_ec_commands.h
@@ -285,6 +285,11 @@ enum host_event_code {
EC_HOST_EVENT_HANG_DETECT = 20,
/* Hang detect logic detected a hang and warm rebooted the AP */
EC_HOST_EVENT_HANG_REBOOT = 21,
+ /* PD MCU triggering host event */
+ EC_HOST_EVENT_PD_MCU = 22,
+
+ /* EC desires to change state of host-controlled USB mux */
+ EC_HOST_EVENT_USB_MUX = 28,

/*
* The high bit of the event mask is not used as a host event code. If
@@ -2905,6 +2910,76 @@ struct ec_params_usb_pd_control {
uint8_t mux;
} __packed;

+#define PD_CTRL_RESP_ENABLED_COMMS (1 << 0) /* Communication enabled */
+#define PD_CTRL_RESP_ENABLED_CONNECTED (1 << 1) /* Device connected */
+#define PD_CTRL_RESP_ENABLED_PD_CAPABLE (1 << 2) /* Partner is PD capable */
+
+struct ec_response_usb_pd_control_v1 {
+ uint8_t enabled;
+ uint8_t role;
+ uint8_t polarity;
+ char state[32];
+} __packed;
+
+#define EC_CMD_USB_PD_PORTS 0x102
+
+struct ec_response_usb_pd_ports {
+ uint8_t num_ports;
+} __packed;
+
+#define EC_CMD_USB_PD_POWER_INFO 0x103
+
+#define PD_POWER_CHARGING_PORT 0xff
+struct ec_params_usb_pd_power_info {
+ uint8_t port;
+} __packed;
+
+enum usb_chg_type {
+ USB_CHG_TYPE_NONE,
+ USB_CHG_TYPE_PD,
+ USB_CHG_TYPE_C,
+ USB_CHG_TYPE_PROPRIETARY,
+ USB_CHG_TYPE_BC12_DCP,
+ USB_CHG_TYPE_BC12_CDP,
+ USB_CHG_TYPE_BC12_SDP,
+ USB_CHG_TYPE_OTHER,
+ USB_CHG_TYPE_VBUS,
+ USB_CHG_TYPE_UNKNOWN,
+};
+
+struct usb_chg_measures {
+ uint16_t voltage_max;
+ uint16_t voltage_now;
+ uint16_t current_max;
+ uint16_t current_lim;
+} __packed;
+
+struct ec_response_usb_pd_power_info {
+ uint8_t role;
+ uint8_t type;
+ uint8_t dualrole;
+ uint8_t reserved1;
+ struct usb_chg_measures meas;
+ uint32_t max_power;
+} __packed;
+
+/* Get info about USB-C SS muxes */
+#define EC_CMD_USB_PD_MUX_INFO 0x11a
+
+struct ec_params_usb_pd_mux_info {
+ uint8_t port; /* USB-C port number */
+} __packed;
+
+/* Flags representing mux state */
+#define USB_PD_MUX_USB_ENABLED (1 << 0)
+#define USB_PD_MUX_DP_ENABLED (1 << 1)
+#define USB_PD_MUX_POLARITY_INVERTED (1 << 2)
+#define USB_PD_MUX_HPD_IRQ (1 << 3)
+
+struct ec_response_usb_pd_mux_info {
+ uint8_t flags; /* USB_PD_MUX_*-encoded USB mux state */
+} __packed;
+
/*****************************************************************************/
/*
* Passthru commands
--
2.9.3
\
 
 \ /
  Last update: 2017-07-17 11:42    [W:0.063 / U:8.000 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site