[PATCH v4 2/3] power: supply: add cros-ec USBPD charger driver.

Enric Balletbo i Serra
2018-05-02T15:44:17Z

From: Sameer Nanda <snanda@chromium.org>

This driver gets various bits of information about what is connected to
USB PD ports from the EC and converts that into power_supply properties.

Signed-off-by: Sameer Nanda <snanda@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
---

Changes in v4:
- [2/3] Drop cros_ec_device->charger as is not used.

Changes in v3:
- [2/3] Add missing POWER_SUPPLY_PROP_USB_TYPE and a list of supported USB types.
- [2/3] Fix SPDX header -> GPL-2.0+
- [2/3] Unregister blocking_notifier_chain on remove.

Changes in v2:
- [2/3] Add SPDX header, use devm_ variant and drop .owner
- [2/3] Removed the PD log functionality (will be send on a follow up patch)
- [2/3] Removed the extra custom sysfs attributes (will be send on a follow up patch)

drivers/power/supply/Kconfig | 10 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/cros_usbpd-charger.c | 544 ++++++++++++++++++++++
3 files changed, 555 insertions(+)
create mode 100644 drivers/power/supply/cros_usbpd-charger.c

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 428b426842f4..046eb23ba6f0 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -624,4 +624,14 @@ config CHARGER_RT9455
help
Say Y to enable support for Richtek RT9455 battery charger.

+config CHARGER_CROS_USBPD
+ tristate "ChromeOS EC based USBPD charger"
+ depends on MFD_CROS_EC
+ default n
+ help
+ Say Y here to enable ChromeOS EC based USBPD charger
+ driver. This driver gets various bits of information about
+ what is connected to USB PD ports from the EC and converts
+ that into power_supply properties.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index e83aa843bcc6..907e26f824b2 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -83,3 +83,4 @@ obj-$(CONFIG_CHARGER_TPS65090) += tps65090-charger.o
obj-$(CONFIG_CHARGER_TPS65217) += tps65217_charger.o
obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
+obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
diff --git a/drivers/power/supply/cros_usbpd-charger.c b/drivers/power/supply/cros_usbpd-charger.c
new file mode 100644
index 000000000000..3a0c96fd1bc1
--- /dev/null
+++ b/drivers/power/supply/cros_usbpd-charger.c
@@ -0,0 +1,544 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Power supply driver for ChromeOS EC based USB PD Charger.
+ *
+ * Copyright (c) 2014 - 2018 Google, Inc
+ */
+
+#include <linux/module.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/slab.h>
+
+#define CHARGER_DIR_NAME "CROS_USBPD_CHARGER%d"
+#define CHARGER_DIR_NAME_LENGTH sizeof(CHARGER_DIR_NAME)
+#define CHARGER_CACHE_UPDATE_DELAY msecs_to_jiffies(500)
+#define CHARGER_MANUFACTURER_MODEL_LENGTH 32
+
+#define DRV_NAME "cros-usbpd-charger"
+
+struct port_data {
+ int port_number;
+ char name[CHARGER_DIR_NAME_LENGTH];
+ char manufacturer[CHARGER_MANUFACTURER_MODEL_LENGTH];
+ char model_name[CHARGER_MANUFACTURER_MODEL_LENGTH];
+ struct power_supply *psy;
+ struct power_supply_desc psy_desc;
+ int psy_usb_type;
+ int psy_online;
+ int psy_status;
+ int psy_current_max;
+ int psy_voltage_max_design;
+ int psy_voltage_now;
+ int psy_power_max;
+ struct charger_data *charger;
+ unsigned long last_update;
+};
+
+struct charger_data {
+ struct device *dev;
+ struct cros_ec_dev *ec_dev;
+ struct cros_ec_device *ec_device;
+ int num_charger_ports;
+ int num_registered_psy;
+ struct port_data *ports[EC_USB_PD_MAX_PORTS];
+ struct notifier_block notifier;
+};
+
+static enum power_supply_property cros_usbpd_charger_props[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_CURRENT_MAX,
+ POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_MODEL_NAME,
+ POWER_SUPPLY_PROP_MANUFACTURER,
+ POWER_SUPPLY_PROP_USB_TYPE
+};
+
+static enum power_supply_usb_type cros_usbpd_charger_usb_types[] = {
+ POWER_SUPPLY_USB_TYPE_UNKNOWN,
+ POWER_SUPPLY_USB_TYPE_SDP,
+ POWER_SUPPLY_USB_TYPE_DCP,
+ POWER_SUPPLY_USB_TYPE_CDP,
+ POWER_SUPPLY_USB_TYPE_C,
+ POWER_SUPPLY_USB_TYPE_PD,
+ POWER_SUPPLY_USB_TYPE_PD_DRP,
+ POWER_SUPPLY_USB_TYPE_APPLE_BRICK_ID
+};
+
+static int cros_usbpd_charger_ec_command(struct charger_data *charger,
+ unsigned int version,
+ unsigned int command,
+ void *outdata,
+ unsigned int outsize,
+ void *indata,
+ unsigned int insize)
+{
+ struct cros_ec_dev *ec_dev = charger->ec_dev;
+ struct cros_ec_command *msg;
+ int ret;
+
+ msg = kzalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ msg->version = version;
+ msg->command = ec_dev->cmd_offset + command;
+ msg->outsize = outsize;
+ msg->insize = insize;
+
+ if (outsize)
+ memcpy(msg->data, outdata, outsize);
+
+ ret = cros_ec_cmd_xfer_status(charger->ec_device, msg);
+ if (ret >= 0 && insize)
+ memcpy(indata, msg->data, insize);
+
+ kfree(msg);
+ return ret;
+}
+
+static int cros_usbpd_charger_get_num_ports(struct charger_data *charger)
+{
+ struct ec_response_usb_pd_ports resp;
+ int ret;
+
+ ret = cros_usbpd_charger_ec_command(charger, 0, EC_CMD_USB_PD_PORTS,
+ NULL, 0, &resp, sizeof(resp));
+ if (ret < 0) {
+ dev_err(charger->dev,
+ "Unable to get the number or ports (err:0x%x)\n", ret);
+ return ret;
+ }
+
+ return resp.num_ports;
+}
+
+static int cros_usbpd_charger_get_discovery_info(struct port_data *port)
+{
+ struct charger_data *charger = port->charger;
+ struct ec_params_usb_pd_discovery_entry resp;
+ struct ec_params_usb_pd_info_request req;
+ int ret;
+
+ req.port = port->port_number;
+
+ ret = cros_usbpd_charger_ec_command(charger, 0,
+ EC_CMD_USB_PD_DISCOVERY,
+ &req, sizeof(req),
+ &resp, sizeof(resp));
+ if (ret < 0) {
+ dev_err(charger->dev,
+ "Unable to query discovery info (err:0x%x)\n", ret);
+ return ret;
+ }
+
+ dev_dbg(charger->dev, "Port %d: VID = 0x%x, PID=0x%x, PTYPE=0x%x\n",
+ port->port_number, resp.vid, resp.pid, resp.ptype);
+
+ snprintf(port->manufacturer, sizeof(port->manufacturer), "%x",
+ resp.vid);
+ snprintf(port->model_name, sizeof(port->model_name), "%x", resp.pid);
+
+ return 0;
+}
+
+static int cros_usbpd_charger_get_power_info(struct port_data *port)
+{
+ struct charger_data *charger = port->charger;
+ struct ec_response_usb_pd_power_info resp;
+ struct ec_params_usb_pd_power_info req;
+ int last_psy_status, last_psy_usb_type;
+ struct device *dev = charger->dev;
+ int ret;
+
+ req.port = port->port_number;
+ ret = cros_usbpd_charger_ec_command(charger, 0,
+ EC_CMD_USB_PD_POWER_INFO,
+ &req, sizeof(req),
+ &resp, sizeof(resp));
+ if (ret < 0) {
+ dev_err(dev, "Unable to query PD power info (err:0x%x)\n", ret);
+ return ret;
+ }
+
+ last_psy_status = port->psy_status;
+ last_psy_usb_type = port->psy_usb_type;
+
+ switch (resp.role) {
+ case USB_PD_PORT_POWER_DISCONNECTED:
+ port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ port->psy_online = 0;
+ break;
+ case USB_PD_PORT_POWER_SOURCE:
+ port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ port->psy_online = 0;
+ break;
+ case USB_PD_PORT_POWER_SINK:
+ port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
+ port->psy_online = 1;
+ break;
+ case USB_PD_PORT_POWER_SINK_NOT_CHARGING:
+ port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ port->psy_online = 1;
+ break;
+ default:
+ dev_err(dev, "Unknown role %d\n", resp.role);
+ break;
+ }
+
+ port->psy_voltage_max_design = resp.meas.voltage_max;
+ port->psy_voltage_now = resp.meas.voltage_now;
+ port->psy_current_max = resp.meas.current_max;
+ port->psy_power_max = resp.max_power;
+
+ switch (resp.type) {
+ case USB_CHG_TYPE_BC12_SDP:
+ case USB_CHG_TYPE_VBUS:
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_SDP;
+ break;
+ case USB_CHG_TYPE_NONE:
+ /*
+ * For dual-role devices when we are a source, the firmware
+ * reports the type as NONE. Report such chargers as type
+ * USB_PD_DRP.
+ */
+ if (resp.role == USB_PD_PORT_POWER_SOURCE && resp.dualrole)
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_PD_DRP;
+ else
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_SDP;
+ break;
+ case USB_CHG_TYPE_OTHER:
+ case USB_CHG_TYPE_PROPRIETARY:
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_APPLE_BRICK_ID;
+ break;
+ case USB_CHG_TYPE_C:
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_C;
+ break;
+ case USB_CHG_TYPE_BC12_DCP:
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_DCP;
+ break;
+ case USB_CHG_TYPE_BC12_CDP:
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_CDP;
+ break;
+ case USB_CHG_TYPE_PD:
+ if (resp.dualrole)
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_PD_DRP;
+ else
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_PD;
+ break;
+ case USB_CHG_TYPE_UNKNOWN:
+ /*
+ * While the EC is trying to determine the type of charger that
+ * has been plugged in, it will report the charger type as
+ * unknown. Additionally since the power capabilities are
+ * unknown, report the max current and voltage as zero.
+ */
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;
+ port->psy_voltage_max_design = 0;
+ port->psy_current_max = 0;
+ break;
+ default:
+ dev_err(dev, "Port %d: default case!\n", port->port_number);
+ port->psy_usb_type = POWER_SUPPLY_USB_TYPE_SDP;
+ }
+
+ port->psy_desc.type = POWER_SUPPLY_TYPE_USB;
+
+ dev_dbg(dev,
+ "Port %d: type=%d vmax=%d vnow=%d cmax=%d clim=%d pmax=%d\n",
+ port->port_number, resp.type, resp.meas.voltage_max,
+ resp.meas.voltage_now, resp.meas.current_max,
+ resp.meas.current_lim, resp.max_power);
+
+ /*
+ * If power supply type or status changed, explicitly call
+ * power_supply_changed. This results in udev event getting generated
+ * and allows user mode apps to react quicker instead of waiting for
+ * their next poll of power supply status.
+ */
+ if (last_psy_usb_type != port->psy_usb_type ||
+ last_psy_status != port->psy_status)
+ power_supply_changed(port->psy);
+
+ return 0;
+}
+
+static int cros_usbpd_charger_get_port_status(struct port_data *port,
+ bool ratelimit)
+{
+ int ret;
+
+ if (ratelimit &&
+ time_is_after_jiffies(port->last_update +
+ CHARGER_CACHE_UPDATE_DELAY))
+ return 0;
+
+ ret = cros_usbpd_charger_get_power_info(port);
+ if (ret < 0)
+ return ret;
+
+ ret = cros_usbpd_charger_get_discovery_info(port);
+ port->last_update = jiffies;
+
+ return ret;
+}
+
+static void cros_usbpd_charger_power_changed(struct power_supply *psy)
+{
+ struct port_data *port = power_supply_get_drvdata(psy);
+ struct charger_data *charger = port->charger;
+ int i;
+
+ for (i = 0; i < charger->num_registered_psy; i++)
+ cros_usbpd_charger_get_port_status(charger->ports[i], false);
+}
+
+static int cros_usbpd_charger_get_prop(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct port_data *port = power_supply_get_drvdata(psy);
+ struct charger_data *charger = port->charger;
+ struct cros_ec_device *ec_device = charger->ec_device;
+ struct device *dev = charger->dev;
+ int ret;
+
+ /* Only refresh ec_port_status for dynamic properties */
+ switch (psp) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ /*
+ * If mkbp_event_supported, then we can be assured that
+ * the driver's state for the online property is consistent
+ * with the hardware. However, if we aren't event driven,
+ * the optimization before to skip an ec_port_status get
+ * and only returned cached values of the online property will
+ * cause a delay in detecting a cable attach until one of the
+ * other properties are read.
+ *
+ * Allow an ec_port_status refresh for online property check
+ * if we're not already online to check for plug events if
+ * not mkbp_event_supported.
+ */
+ if (ec_device->mkbp_event_supported || port->psy_online)
+ break;
+ case POWER_SUPPLY_PROP_CURRENT_MAX:
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ ret = cros_usbpd_charger_get_port_status(port, true);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get port status (err:0x%x)\n",
+ ret);
+ return -EINVAL;
+ }
+ break;
+ default:
+ break;
+ }
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ val->intval = port->psy_online;
+ break;
+ case POWER_SUPPLY_PROP_STATUS:
+ val->intval = port->psy_status;
+ break;
+ case POWER_SUPPLY_PROP_CURRENT_MAX:
+ val->intval = port->psy_current_max * 1000;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+ val->intval = port->psy_voltage_max_design * 1000;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ val->intval = port->psy_voltage_now * 1000;
+ break;
+ case POWER_SUPPLY_PROP_USB_TYPE:
+ val->intval = port->psy_usb_type;
+ break;
+ case POWER_SUPPLY_PROP_MODEL_NAME:
+ val->strval = port->model_name;
+ break;
+ case POWER_SUPPLY_PROP_MANUFACTURER:
+ val->strval = port->manufacturer;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int cros_usbpd_charger_ec_event(struct notifier_block *nb,
+ unsigned long queued_during_suspend,
+ void *_notify)
+{
+ struct cros_ec_device *ec_device;
+ struct charger_data *charger;
+ struct device *dev;
+ u32 host_event;
+
+ charger = container_of(nb, struct charger_data, notifier);
+ ec_device = charger->ec_device;
+ dev = charger->dev;
+
+ host_event = cros_ec_get_host_event(ec_device);
+ if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
+ cros_usbpd_charger_power_changed(charger->ports[0]->psy);
+ return NOTIFY_OK;
+ } else {
+ return NOTIFY_DONE;
+ }
+}
+
+static void cros_usbpd_charger_unregister_notifier(void *data)
+{
+ struct charger_data *charger = data;
+ struct cros_ec_device *ec_device = charger->ec_device;
+
+ blocking_notifier_chain_unregister(&ec_device->event_notifier,
+ &charger->notifier);
+}
+
+static int cros_usbpd_charger_probe(struct platform_device *pd)
+{
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+ struct cros_ec_device *ec_device = ec_dev->ec_dev;
+ struct power_supply_desc *psy_desc;
+ struct device *dev = &pd->dev;
+ struct charger_data *charger;
+ struct power_supply *psy;
+ struct port_data *port;
+ int ret = -EINVAL;
+ int i;
+
+ charger = devm_kzalloc(dev, sizeof(struct charger_data),
+ GFP_KERNEL);
+ if (!charger)
+ return -ENOMEM;
+
+ charger->dev = dev;
+ charger->ec_dev = ec_dev;
+ charger->ec_device = ec_device;
+
+ platform_set_drvdata(pd, charger);
+
+ charger->num_charger_ports = cros_usbpd_charger_get_num_ports(charger);
+ if (charger->num_charger_ports <= 0) {
+ /*
+ * This can happen on a system that doesn't support USB PD.
+ * Log a message, but no need to warn.
+ */
+ dev_info(dev, "No charging ports found\n");
+ ret = -ENODEV;
+ goto fail_nowarn;
+ }
+
+ for (i = 0; i < charger->num_charger_ports; i++) {
+ struct power_supply_config psy_cfg = {};
+
+ port = devm_kzalloc(dev, sizeof(struct port_data), GFP_KERNEL);
+ if (!port) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ port->charger = charger;
+ port->port_number = i;
+ sprintf(port->name, CHARGER_DIR_NAME, i);
+
+ psy_desc = &port->psy_desc;
+ psy_desc->name = port->name;
+ psy_desc->type = POWER_SUPPLY_TYPE_USB;
+ psy_desc->get_property = cros_usbpd_charger_get_prop;
+ psy_desc->external_power_changed =
+ cros_usbpd_charger_power_changed;
+ psy_desc->properties = cros_usbpd_charger_props;
+ psy_desc->num_properties =
+ ARRAY_SIZE(cros_usbpd_charger_props);
+ psy_desc->usb_types = cros_usbpd_charger_usb_types;
+ psy_desc->num_usb_types =
+ ARRAY_SIZE(cros_usbpd_charger_usb_types);
+ psy_cfg.drv_data = port;
+
+ psy = devm_power_supply_register_no_ws(dev, psy_desc,
+ &psy_cfg);
+ if (IS_ERR(psy)) {
+ dev_err(dev, "Failed to register power supply\n");
+ continue;
+ }
+ port->psy = psy;
+
+ charger->ports[charger->num_registered_psy++] = port;
+ }
+
+ if (!charger->num_registered_psy) {
+ ret = -ENODEV;
+ dev_err(dev, "No power supplies registered\n");
+ goto fail;
+ }
+
+ if (ec_device->mkbp_event_supported) {
+ /* Get PD events from the EC */
+ charger->notifier.notifier_call = cros_usbpd_charger_ec_event;
+ ret = blocking_notifier_chain_register(
+ &ec_device->event_notifier,
+ &charger->notifier);
+ if (ret < 0) {
+ dev_warn(dev, "failed to register notifier\n");
+ } else {
+ ret = devm_add_action_or_reset(dev,
+ cros_usbpd_charger_unregister_notifier,
+ charger);
+ if (ret < 0)
+ goto fail;
+ }
+ }
+
+ return 0;
+
+fail:
+ WARN(1, "%s: Failing probe (err:0x%x)\n", dev_name(dev), ret);
+
+fail_nowarn:
+ dev_info(dev, "Failing probe (err:0x%x)\n", ret);
+ return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cros_usbpd_charger_resume(struct device *dev)
+{
+ struct charger_data *charger = dev_get_drvdata(dev);
+ int i;
+
+ if (!charger)
+ return 0;
+
+ for (i = 0; i < charger->num_registered_psy; i++) {
+ power_supply_changed(charger->ports[i]->psy);
+ charger->ports[i]->last_update =
+ jiffies - CHARGER_CACHE_UPDATE_DELAY;
+ }
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(cros_usbpd_charger_pm_ops, NULL,
+ cros_usbpd_charger_resume);
+
+static struct platform_driver cros_usbpd_charger_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .pm = &cros_usbpd_charger_pm_ops,
+ },
+ .probe = cros_usbpd_charger_probe
+};
+
+module_platform_driver(cros_usbpd_charger_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ChromeOS EC USBPD charger");
+MODULE_ALIAS("platform:" DRV_NAME);
--
2.17.0