diff mbox

[2/3] power: supply: add cros-ec USB PD charger driver.

Message ID 20180117175932.20636-3-enric.balletbo@collabora.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Enric Balletbo i Serra Jan. 17, 2018, 5:59 p.m. UTC
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>
---
 drivers/power/supply/Kconfig              |  11 +
 drivers/power/supply/Makefile             |   1 +
 drivers/power/supply/cros_usbpd-charger.c | 953 ++++++++++++++++++++++++++++++
 include/linux/mfd/cros_ec.h               |   3 +
 4 files changed, 968 insertions(+)
 create mode 100644 drivers/power/supply/cros_usbpd-charger.c

Comments

Aishwarya Pant Jan. 18, 2018, 5:56 a.m. UTC | #1
On Wed, Jan 17, 2018 at 06:59:31PM +0100, Enric Balletbo i Serra wrote:
> 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>
> ---
>  drivers/power/supply/Kconfig              |  11 +
>  drivers/power/supply/Makefile             |   1 +
>  drivers/power/supply/cros_usbpd-charger.c | 953 ++++++++++++++++++++++++++++++
>  include/linux/mfd/cros_ec.h               |   3 +
>  4 files changed, 968 insertions(+)
>  create mode 100644 drivers/power/supply/cros_usbpd-charger.c

<snip>

> +static DEVICE_ATTR(ext_current_lim, 0664, get_ec_ext_current_lim,
> +		   set_ec_ext_current_lim);
> +static DEVICE_ATTR(ext_voltage_lim, 0664, get_ec_ext_voltage_lim,
> +		   set_ec_ext_voltage_lim);
> +

Hi

I see that you have added new files to the sysfs ABI. It would probably be a
good idea to have these new interfaces documented in Documentation/ABI.

Aishwarya

> +static struct attribute *__ext_power_cmds_attrs[] = {
> +	&dev_attr_ext_current_lim.attr,
> +	&dev_attr_ext_voltage_lim.attr,
> +	NULL,
> +};

<snip>
Lee Jones Jan. 23, 2018, 9:54 a.m. UTC | #2
On Wed, 17 Jan 2018, Enric Balletbo i Serra wrote:

> 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>
> ---
>  drivers/power/supply/Kconfig              |  11 +
>  drivers/power/supply/Makefile             |   1 +
>  drivers/power/supply/cros_usbpd-charger.c | 953 ++++++++++++++++++++++++++++++

>  include/linux/mfd/cros_ec.h               |   3 +

Acked-by: Lee Jones <lee.jones@linaro.org>

>  4 files changed, 968 insertions(+)
>  create mode 100644 drivers/power/supply/cros_usbpd-charger.c
Sebastian Reichel Feb. 9, 2018, 11:57 a.m. UTC | #3
Hi Enric,

On Wed, Jan 17, 2018 at 06:59:31PM +0100, Enric Balletbo i Serra wrote:
> 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>
> ---
>  drivers/power/supply/Kconfig              |  11 +
>  drivers/power/supply/Makefile             |   1 +
>  drivers/power/supply/cros_usbpd-charger.c | 953 ++++++++++++++++++++++++++++++
>  include/linux/mfd/cros_ec.h               |   3 +
>  4 files changed, 968 insertions(+)
>  create mode 100644 drivers/power/supply/cros_usbpd-charger.c

Documentation for custom sysfs files is missing.

> diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
> index 428b426842f4..641503c1d40a 100644
> --- a/drivers/power/supply/Kconfig
> +++ b/drivers/power/supply/Kconfig
> @@ -624,4 +624,15 @@ config CHARGER_RT9455
>  	help
>  	  Say Y to enable support for Richtek RT9455 battery charger.
>  
> +config CHARGER_CROS_USB_PD
> +	tristate "Chrome OS EC based USB PD charger"
> +	depends on MFD_CROS_EC
> +	select RTC_LIB
> +	default n
> +	help
> +	  Say Y here to enable Chrome OS EC based USB PD 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..c412fe8b562d 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_USB_PD)	+= 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..1c48185f8163
> --- /dev/null
> +++ b/drivers/power/supply/cros_usbpd-charger.c
> @@ -0,0 +1,953 @@

Please add SPDX header.

> +/*
> + * Power supply driver for ChromeOS EC based USB PD Charger.
> + *
> + * Copyright (c) 2014 - 2018 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.
> + */
> +
> +#include <linux/fs.h>
> +#include <linux/ktime.h>
> +#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/rtc.h>
> +#include <linux/slab.h>
> +
> +#define CROS_USB_PD_MAX_LOG_ENTRIES	30
> +
> +#define CROS_USB_PD_LOG_UPDATE_DELAY msecs_to_jiffies(60000)
> +#define CROS_USB_PD_CACHE_UPDATE_DELAY msecs_to_jiffies(500)
> +
> +/* Buffer + macro for building PDLOG string */
> +#define BUF_SIZE 80
> +#define APPEND_STRING(buf, len, str, ...) ((len) += \
> +	snprintf((buf) + (len), max(BUF_SIZE - (len), 0), (str), ##__VA_ARGS__))
> +
> +#define CHARGER_DIR_NAME		"CROS_USB_PD_CHARGER%d"
> +#define CHARGER_DIR_NAME_LENGTH		sizeof(CHARGER_DIR_NAME)
> +#define DRV_NAME "cros-usb-pd-charger"
> +
> +#define MANUFACTURER_MODEL_LENGTH	32
> +
> +struct port_data {
> +	int port_number;
> +	char name[CHARGER_DIR_NAME_LENGTH];
> +	char manufacturer[MANUFACTURER_MODEL_LENGTH];
> +	char model_name[MANUFACTURER_MODEL_LENGTH];
> +	struct power_supply *psy;
> +	struct power_supply_desc psy_desc;
> +	int psy_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 delayed_work log_work;
> +	struct workqueue_struct *log_workqueue;
> +	struct notifier_block notifier;
> +	bool suspended;
> +};
> +
> +#define EC_MAX_IN_SIZE EC_PROTO2_MAX_REQUEST_SIZE
> +#define EC_MAX_OUT_SIZE EC_PROTO2_MAX_RESPONSE_SIZE
> +u8 ec_inbuf[EC_MAX_IN_SIZE];
> +u8 ec_outbuf[EC_MAX_OUT_SIZE];
> +
> +static enum power_supply_property cros_usb_pd_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_CHARGE_CONTROL_LIMIT_MAX,
> +	POWER_SUPPLY_PROP_MODEL_NAME,
> +	POWER_SUPPLY_PROP_MANUFACTURER,
> +};
> +
> +/* Current external voltage/current limit in mV/mA. Default to none. */
> +static u16 ext_voltage_lim = EC_POWER_LIMIT_NONE;
> +static u16 ext_current_lim = EC_POWER_LIMIT_NONE;
> +
> +static int ec_command(struct charger_data *charger, int version, int command,
> +		      u8 *outdata, int outsize, u8 *indata,
> +		      int insize)
> +{
> +	struct cros_ec_device *ec_device = charger->ec_device;
> +	struct cros_ec_dev *ec_dev = charger->ec_dev;
> +	struct cros_ec_command *msg;
> +	int ret;
> +
> +	msg = kzalloc(sizeof(*msg) + max(insize, outsize), 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(ec_device, msg);
> +	if (ret > 0 && insize)
> +		memcpy(indata, msg->data, insize);
> +
> +	kfree(msg);
> +	return ret;
> +}
> +
> +static int set_ec_usb_pd_override_ports(struct charger_data *charger,
> +					int port_num)
> +{
> +	struct device *dev = charger->dev;
> +	struct ec_params_charge_port_override req;
> +	int ret;
> +
> +	req.override_port = port_num;
> +
> +	ret = ec_command(charger, 0, EC_CMD_PD_CHARGE_PORT_OVERRIDE,
> +			 (u8 *)&req, sizeof(req),
> +			 NULL, 0);
> +	if (ret < 0) {
> +		dev_info(dev, "Port Override command returned 0x%x\n", ret);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int get_ec_num_ports(struct charger_data *charger, int *num_ports)
> +{
> +	struct device *dev = charger->dev;
> +	struct ec_response_usb_pd_ports *resp =
> +	    (struct ec_response_usb_pd_ports *)ec_inbuf;
> +	int ret;
> +
> +	*num_ports = 0;
> +	ret = ec_command(charger, 0, EC_CMD_USB_PD_PORTS,
> +			 NULL, 0, ec_inbuf, EC_MAX_IN_SIZE);
> +	if (ret < 0) {
> +		dev_err(dev, "Unable to query PD ports (err:0x%x)\n", ret);
> +		return ret;
> +	}
> +	*num_ports = resp->num_ports;
> +	dev_dbg(dev, "Num ports = %d\n", *num_ports);
> +
> +	return 0;
> +}
> +
> +static int get_ec_usb_pd_discovery_info(struct port_data *port)
> +{
> +	struct charger_data *charger = port->charger;
> +	struct device *dev = charger->dev;
> +	struct ec_params_usb_pd_info_request req;
> +	struct ec_params_usb_pd_discovery_entry resp;
> +	int ret;
> +
> +	req.port = port->port_number;
> +
> +	ret = ec_command(charger, 0, EC_CMD_USB_PD_DISCOVERY,
> +			 (u8 *)&req, sizeof(req),
> +			 (u8 *)&resp, sizeof(resp));
> +	if (ret < 0) {
> +		dev_err(dev, "Unable to query Discovery info (err:0x%x)\n",
> +			ret);
> +		return -EINVAL;
> +	}
> +
> +	dev_dbg(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, MANUFACTURER_MODEL_LENGTH, "%x", resp.vid);
> +	snprintf(port->model_name, MANUFACTURER_MODEL_LENGTH, "%x", resp.pid);
> +
> +	return 0;
> +}
> +
> +static int get_ec_usb_pd_power_info(struct port_data *port)
> +{
> +	struct charger_data *charger = port->charger;
> +	struct device *dev = charger->dev;
> +	struct ec_params_usb_pd_power_info req;
> +	struct ec_response_usb_pd_power_info resp;
> +	char role_str[80];

const char *role_str;

> +	int ret, last_psy_status, last_psy_type;
> +
> +	req.port = port->port_number;
> +	ret = ec_command(charger, 0, EC_CMD_USB_PD_POWER_INFO,
> +			 (u8 *)&req, sizeof(req),
> +			 (u8 *)&resp, sizeof(resp));
> +	if (ret < 0) {
> +		dev_err(dev, "Unable to query PD power info (err:0x%x)\n", ret);
> +		return -EINVAL;
> +	}
> +
> +	last_psy_status = port->psy_status;
> +	last_psy_type = port->psy_type;
> +
> +	switch (resp.role) {
> +	case USB_PD_PORT_POWER_DISCONNECTED:
> +		snprintf(role_str, sizeof(role_str), "%s", "DISCONNECTED");

role_str = "DISCONNECTED";

> +		port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +		port->psy_online = 0;
> +		break;
> +	case USB_PD_PORT_POWER_SOURCE:
> +		snprintf(role_str, sizeof(role_str), "%s", "SOURCE");
> +		port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +		port->psy_online = 0;
> +		break;
> +	case USB_PD_PORT_POWER_SINK:
> +		snprintf(role_str, sizeof(role_str), "%s", "SINK");
> +		port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
> +		port->psy_online = 1;
> +		break;
> +	case USB_PD_PORT_POWER_SINK_NOT_CHARGING:
> +		snprintf(role_str, sizeof(role_str), "%s", "NOT CHARGING");
> +		port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +		port->psy_online = 1;
> +		break;
> +	default:
> +		snprintf(role_str, sizeof(role_str), "%s", "UNKNOWN");
> +		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_type = POWER_SUPPLY_TYPE_USB;
> +		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_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
> +		else
> +			port->psy_type = POWER_SUPPLY_TYPE_USB;
> +		break;
> +	case USB_CHG_TYPE_OTHER:
> +	case USB_CHG_TYPE_PROPRIETARY:
> +		port->psy_type = POWER_SUPPLY_TYPE_APPLE_BRICK_ID;
> +		break;
> +	case USB_CHG_TYPE_C:
> +		port->psy_type = POWER_SUPPLY_TYPE_USB_TYPE_C;
> +		break;
> +	case USB_CHG_TYPE_BC12_DCP:
> +		port->psy_type = POWER_SUPPLY_TYPE_USB_DCP;
> +		break;
> +	case USB_CHG_TYPE_BC12_CDP:
> +		port->psy_type = POWER_SUPPLY_TYPE_USB_CDP;
> +		break;
> +	case USB_CHG_TYPE_PD:
> +		if (resp.dualrole)
> +			port->psy_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
> +		else
> +			port->psy_type = POWER_SUPPLY_TYPE_USB_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. Treat this case as a dedicated charger since we
> +		 * don't know any better just yet. Additionally since the power
> +		 * capabilities are unknown, report the max current and voltage
> +		 * as zero.
> +		 */
> +		port->psy_type = POWER_SUPPLY_TYPE_MAINS;
> +		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_type = POWER_SUPPLY_TYPE_USB;
> +	}
> +
> +	port->psy_desc.type = port->psy_type;
> +
> +	dev_dbg(dev,
> +		"Port %d: %s type=%d=vmax=%d vnow=%d cmax=%d clim=%d pmax=%d\n",
> +		port->port_number, role_str, 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_type != port->psy_type ||
> +	    last_psy_status != port->psy_status) {
> +		dev_dbg(dev, "Port %d: Calling power_supply_changed\n",
> +			port->port_number);
> +		power_supply_changed(port->psy);
> +	}
> +
> +	return 0;
> +}
> +
> +static int get_ec_port_status(struct port_data *port, bool ratelimit)
> +{
> +	int ret;
> +
> +	if (ratelimit &&
> +	    time_is_after_jiffies(port->last_update +
> +				  CROS_USB_PD_CACHE_UPDATE_DELAY))
> +		return 0;
> +
> +	ret = get_ec_usb_pd_power_info(port);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = get_ec_usb_pd_discovery_info(port);
> +	port->last_update = jiffies;
> +
> +	return ret;
> +}
> +
> +static void cros_usb_pd_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++)
> +		get_ec_port_status(charger->ports[i], false);
> +}
> +
> +static int cros_usb_pd_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 device *dev = charger->dev;
> +	struct cros_ec_device *ec_device = charger->ec_device;
> +	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:
> +	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +		ret = get_ec_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:
> +		/* TODO: change this to voltage_now. */

I don't understand this TODO.

> +		val->intval = port->psy_voltage_now * 1000;
> +		break;
> +	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +		/* TODO: send a TBD host command to the EC. */

So POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX is not implemented at
all?

> +		val->intval = 0;
> +		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_usb_pd_charger_set_prop(struct power_supply *psy,
> +				    enum power_supply_property psp,
> +				    const union power_supply_propval *val)
> +{
> +	struct port_data *port = power_supply_get_drvdata(psy);
> +	struct charger_data *charger = port->charger;
> +	int port_number;
> +
> +	switch (psp) {
> +	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +		/*
> +		 * A value of -1 implies switching to battery as the power
> +		 * source. Any other value implies using this port as the
> +		 * power source.
> +		 */
> +		port_number = val->intval;
> +		if (port_number != -1)
> +			port_number = port->port_number;
> +		return set_ec_usb_pd_override_ports(charger, port_number);

This looks strange. Can you elaborate?

> +	default:
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int cros_usb_pd_charger_is_writeable(struct power_supply *psy,
> +		enum power_supply_property psp)
> +{
> +	int ret;
> +
> +	switch (psp) {
> +	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +		ret = 1;
> +		break;
> +	default:
> +		ret = 0;
> +	}
> +
> +	return ret;
> +}
> +
> +static void cros_usb_pd_print_log_entry(struct ec_response_pd_log *r,
> +					ktime_t tstamp)
> +{
> +	static const char * const fault_names[] = {
> +		"---", "OCP", "fast OCP", "OVP", "Discharge"
> +	};
> +	static const char * const role_names[] = {
> +		"Disconnected", "SRC", "SNK", "SNK (not charging)"
> +	};
> +	static const char * const chg_type_names[] = {
> +		"None", "PD", "Type-C", "Proprietary",
> +		"DCP", "CDP", "SDP", "Other", "VBUS"
> +	};
> +	int i;
> +	int role_idx, type_idx;
> +	const char *fault, *role, *chg_type;
> +	struct usb_chg_measures *meas;
> +	struct mcdp_info *minfo;
> +	struct rtc_time rt;
> +	u64 msecs;
> +	int len = 0;
> +	char buf[BUF_SIZE + 1];
> +
> +	/* the timestamp is the number of 1024th of seconds in the past */
> +	tstamp = ktime_sub_us(tstamp,
> +		 (u64)r->timestamp << PD_LOG_TIMESTAMP_SHIFT);
> +	rt = rtc_ktime_to_tm(tstamp);
> +
> +	switch (r->type) {
> +	case PD_EVENT_MCU_CHARGE:
> +		if (r->data & CHARGE_FLAGS_OVERRIDE)
> +			APPEND_STRING(buf, len, "override ");
> +		if (r->data & CHARGE_FLAGS_DELAYED_OVERRIDE)
> +			APPEND_STRING(buf, len, "pending_override ");
> +		role_idx = r->data & CHARGE_FLAGS_ROLE_MASK;
> +		role = role_idx < ARRAY_SIZE(role_names) ?
> +			role_names[role_idx] : "Unknown";
> +		type_idx = (r->data & CHARGE_FLAGS_TYPE_MASK)
> +			 >> CHARGE_FLAGS_TYPE_SHIFT;
> +		chg_type = type_idx < ARRAY_SIZE(chg_type_names) ?
> +			chg_type_names[type_idx] : "???";
> +		meas = (struct usb_chg_measures *)r->payload;
> +
> +		if ((role_idx == USB_PD_PORT_POWER_DISCONNECTED) ||
> +		    (role_idx == USB_PD_PORT_POWER_SOURCE)) {
> +			APPEND_STRING(buf, len, "%s", role);
> +
> +			if ((role_idx == USB_PD_PORT_POWER_SOURCE) &&
> +			    (meas->current_max))
> +				APPEND_STRING(buf, len, " %dmA",
> +					      meas->current_max);
> +
> +			break;
> +		}
> +
> +		APPEND_STRING(buf, len, "%s %s %s %dmV max %dmV / %dmA", role,
> +			r->data & CHARGE_FLAGS_DUAL_ROLE ? "DRP" : "Charger",
> +			chg_type,
> +			meas->voltage_now,
> +			meas->voltage_max,
> +			meas->current_max);
> +		break;
> +	case PD_EVENT_ACC_RW_FAIL:
> +		APPEND_STRING(buf, len, "RW signature check failed");
> +		break;
> +	case PD_EVENT_PS_FAULT:
> +		fault = r->data < ARRAY_SIZE(fault_names) ? fault_names[r->data]
> +							  : "???";
> +		APPEND_STRING(buf, len, "Power supply fault: %s", fault);
> +		break;
> +	case PD_EVENT_VIDEO_DP_MODE:
> +		APPEND_STRING(buf, len, "DP mode %sabled",
> +			      (r->data == 1) ? "en" : "dis");
> +		break;
> +	case PD_EVENT_VIDEO_CODEC:
> +		minfo = (struct mcdp_info *)r->payload;
> +		APPEND_STRING(buf, len,
> +			      "HDMI info: family:%04x chipid:%04x "
> +			      "irom:%d.%d.%d fw:%d.%d.%d",
> +			      MCDP_FAMILY(minfo->family),
> +			      MCDP_CHIPID(minfo->chipid),
> +			      minfo->irom.major, minfo->irom.minor,
> +			      minfo->irom.build, minfo->fw.major,
> +			      minfo->fw.minor, minfo->fw.build);
> +		break;

video codec?

> +	default:
> +		APPEND_STRING(buf, len,
> +			"Event %02x (%04x) [", r->type, r->data);
> +		for (i = 0; i < PD_LOG_SIZE(r->size_port); i++)
> +			APPEND_STRING(buf, len, "%02x ", r->payload[i]);
> +		APPEND_STRING(buf, len, "]");
> +		break;
> +	}
> +
> +	msecs = ktime_to_ms(tstamp);
> +	do_div(msecs, MSEC_PER_SEC);
> +	pr_info("PDLOG %d/%02d/%02d %02d:%02d:%02d.%03lld P%d %s\n",
> +		rt.tm_year + 1900, rt.tm_mon + 1, rt.tm_mday,
> +		rt.tm_hour, rt.tm_min, rt.tm_sec, msecs,
> +		PD_LOG_PORT(r->size_port), buf);
> +}
> +
> +static void cros_usb_pd_log_check(struct work_struct *work)
> +{
> +	struct charger_data *charger = container_of(to_delayed_work(work),
> +		struct charger_data, log_work);
> +	struct device *dev = charger->dev;
> +	union {
> +		struct ec_response_pd_log r;
> +		u32 words[8]; /* space for the payload */
> +	} u;
> +	int ret;
> +	int entries = 0;
> +	ktime_t now;
> +
> +	if (charger->suspended) {
> +		dev_dbg(dev, "Suspended...bailing out\n");
> +		return;
> +	}
> +
> +	while (entries++ < CROS_USB_PD_MAX_LOG_ENTRIES) {
> +		ret = ec_command(charger, 0, EC_CMD_PD_GET_LOG_ENTRY,
> +				 NULL, 0, (u8 *)&u, sizeof(u));
> +		now = ktime_get_real();
> +		if (ret < 0) {
> +			dev_dbg(dev, "Cannot get PD log %d\n", ret);
> +			break;
> +		}
> +		if (u.r.type == PD_EVENT_NO_ENTRY)
> +			break;
> +
> +		cros_usb_pd_print_log_entry(&u.r, now);
> +	}
> +
> +	queue_delayed_work(charger->log_workqueue, &charger->log_work,
> +		CROS_USB_PD_LOG_UPDATE_DELAY);
> +}

Is there a good reason to have this log in dmesg? It looks more
suitable for debugfs.

> +static int cros_usb_pd_ec_event(struct notifier_block *nb,
> +	unsigned long queued_during_suspend, void *_notify)
> +{
> +	struct charger_data *charger;
> +	struct device *dev;
> +	struct cros_ec_device *ec_device;
> +	u32 host_event;
> +
> +	charger = container_of(nb, struct charger_data, notifier);
> +	dev = charger->dev;
> +	ec_device = charger->ec_device;
> +
> +	host_event = cros_ec_get_host_event(ec_device);
> +	if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
> +		cros_usb_pd_charger_power_changed(charger->ports[0]->psy);
> +		return NOTIFY_OK;
> +	} else {
> +		return NOTIFY_DONE;
> +	}
> +}
> +
> +static char *charger_supplied_to[] = {"cros-usb_pd-charger"};

What are you trying to do here?

> +static int cros_usb_pd_charger_probe(struct platform_device *pd)
> +{
> +	struct device *dev = &pd->dev;
> +	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
> +	struct cros_ec_device *ec_device;
> +	struct charger_data *charger;
> +	struct port_data *port;
> +	struct power_supply_desc *psy_desc;
> +	struct power_supply *psy;
> +	int i;
> +	int ret = -EINVAL;
> +
> +	if (!ec_dev) {
> +		dev_err(dev, "No EC dev found\n");
> +		return -EINVAL;
> +	}
> +
> +	ec_device = ec_dev->ec_dev;
> +	if (!ec_device) {
> +		dev_err(dev, "No EC device found.\n");
> +		return -EINVAL;
> +	}
> +
> +	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);
> +
> +	if ((get_ec_num_ports(charger, &charger->num_charger_ports) < 0) ||
> +	    !charger->num_charger_ports) {
> +		/*
> +		 * 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_usb_pd_charger_get_prop;
> +		psy_desc->set_property = cros_usb_pd_charger_set_prop;
> +		psy_desc->property_is_writeable =
> +					cros_usb_pd_charger_is_writeable;
> +		psy_desc->external_power_changed =
> +					cros_usb_pd_charger_power_changed;
> +		psy_desc->properties = cros_usb_pd_charger_props;
> +		psy_desc->num_properties =
> +					ARRAY_SIZE(cros_usb_pd_charger_props);
> +
> +		psy_cfg.drv_data = port;
> +		psy_cfg.supplied_to = charger_supplied_to;
> +		psy_cfg.num_supplicants = ARRAY_SIZE(charger_supplied_to);
> +
> +		psy = power_supply_register_no_ws(dev, psy_desc, &psy_cfg);

Use devm_ variant.

> +		if (IS_ERR(psy)) {
> +			dev_err(dev, "Failed to register power supply\n");
> +			continue;
> +		}
> +		port->psy = psy;
> +
> +		charger->ports[charger->num_registered_psy++] = port;
> +		ec_device->charger = psy;
> +	}
> +
> +	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_usb_pd_ec_event;
> +		ret = blocking_notifier_chain_register(
> +						&ec_device->event_notifier,
> +						&charger->notifier);
> +		if (ret < 0)
> +			dev_warn(dev, "failed to register notifier\n");
> +	}
> +
> +	/* Retrieve PD event logs periodically */
> +	INIT_DELAYED_WORK(&charger->log_work, cros_usb_pd_log_check);
> +	charger->log_workqueue =
> +		create_singlethread_workqueue("cros_usb_pd_log");
> +	queue_delayed_work(charger->log_workqueue, &charger->log_work,
> +		CROS_USB_PD_LOG_UPDATE_DELAY);
> +
> +	return 0;
> +
> +fail:
> +	WARN(1, "%s: Failing probe (err:0x%x)\n", dev_name(dev), ret);
> +
> +fail_nowarn:
> +	if (charger) {
> +		ec_device->charger = NULL;
> +		for (i = 0; i < charger->num_registered_psy; i++) {
> +			port = charger->ports[i];
> +			power_supply_unregister(port->psy);
> +			devm_kfree(dev, port);
> +		}
> +		platform_set_drvdata(pd, NULL);
> +		devm_kfree(dev, charger);
> +	}

This can be removed (see comments to cros_usb_pd_charger_remove).

> +
> +	dev_info(dev, "Failing probe (err:0x%x)\n", ret);
> +	return ret;
> +}
> +
> +static int cros_usb_pd_charger_remove(struct platform_device *pd)
> +{
> +	struct charger_data *charger = platform_get_drvdata(pd);
> +	struct cros_ec_device *ec_device = charger->ec_device;
> +	struct device *dev = charger->dev;
> +	struct port_data *port;
> +	int i;
> +
> +	if (charger) {
> +		ec_device->charger = NULL;
> +		for (i = 0; i < charger->num_registered_psy; i++) {
> +			port = charger->ports[i];
> +			power_supply_unregister(port->psy);
> +			devm_kfree(dev, port);
> +		}
> +		flush_delayed_work(&charger->log_work);
> +		platform_set_drvdata(pd, NULL);
> +		devm_kfree(dev, charger);
> +	}
> +	return 0;

The devm_kfree is not needed, unsetting platform driver data is not
needed and you can drop power_supply_unregister after using the
devm_ registration function. I think the entire function can be reduced
to a

cancel_delayed_work_sync()

call (flush looks wrong btw. I suspect this might crash your system
10 minutes after  module removal).

> +}

> +
> +#ifdef CONFIG_PM_SLEEP
> +static int cros_usb_pd_charger_resume(struct device *dev)
> +{
> +	struct charger_data *charger = dev_get_drvdata(dev);
> +	int i;
> +
> +	if (!charger)
> +		return 0;
> +
> +	charger->suspended = false;
> +
> +	for (i = 0; i < charger->num_registered_psy; i++) {
> +		power_supply_changed(charger->ports[i]->psy);
> +		charger->ports[i]->last_update =
> +				jiffies - CROS_USB_PD_CACHE_UPDATE_DELAY;
> +	}
> +	queue_delayed_work(charger->log_workqueue, &charger->log_work,
> +		CROS_USB_PD_LOG_UPDATE_DELAY);
> +
> +	return 0;
> +}
> +
> +static int cros_usb_pd_charger_suspend(struct device *dev)
> +{
> +	struct charger_data *charger = dev_get_drvdata(dev);
> +
> +	charger->suspended = true;
> +
> +	if (charger)
> +		flush_delayed_work(&charger->log_work);
> +	return 0;

I think it's cleaner to cancel the delayed work and requeue on
resume. with this you can just drop the charger-suspended variable.

> +}
> +#endif
> +
> +static int set_ec_ext_power_limit(struct cros_ec_dev *ec,
> +				  u16 current_lim, u16 voltage_lim)
> +{
> +	struct ec_params_external_power_limit_v1 *req;
> +	struct cros_ec_command *msg;
> +	int ret;
> +
> +	msg = kzalloc(sizeof(*msg) + sizeof(*req), GFP_KERNEL);
> +	if (!msg)
> +		return -ENOMEM;
> +
> +	req = (struct ec_params_external_power_limit_v1 *)msg->data;
> +
> +	req->current_lim = current_lim;
> +	req->voltage_lim = voltage_lim;
> +
> +	msg->version = 1;
> +	msg->command = ec->cmd_offset + EC_CMD_EXTERNAL_POWER_LIMIT;
> +	msg->outsize = sizeof(*req);
> +
> +	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
> +	if (ret < 0) {
> +		dev_warn(ec->dev,
> +			 "External power limit command returned 0x%x\n",
> +			 ret);
> +		ret = -EINVAL;
> +	} else {
> +		ret = 0;
> +	}
> +
> +	kfree(msg);
> +	return ret;
> +}
> +
> +static ssize_t get_ec_ext_current_lim(struct device *dev,
> +				      struct device_attribute *attr,
> +				      char *buf)
> +{
> +	return scnprintf(buf, PAGE_SIZE, "%d\n", ext_current_lim);
> +}
> +
> +static ssize_t set_ec_ext_current_lim(struct device *dev,
> +				      struct device_attribute *attr,
> +				      const char *buf, size_t count)
> +{
> +	int ret;
> +	u16 tmp_val;
> +	struct cros_ec_dev *ec = container_of(
> +			dev, struct cros_ec_dev, class_dev);
> +
> +	if (kstrtou16(buf, 0, &tmp_val) < 0)
> +		return -EINVAL;
> +
> +	ret = set_ec_ext_power_limit(ec, tmp_val, ext_voltage_lim);
> +	if (ret < 0)
> +		return ret;
> +
> +	ext_current_lim = tmp_val;
> +	if (ext_current_lim == EC_POWER_LIMIT_NONE)
> +		dev_info(ec->dev, "External current limit removed\n");
> +	else
> +		dev_info(ec->dev, "External current limit set to %dmA\n",
> +			 ext_current_lim);
> +
> +	return count;
> +}
> +
> +static ssize_t get_ec_ext_voltage_lim(struct device *dev,
> +				      struct device_attribute *attr,
> +				      char *buf)
> +{
> +	return scnprintf(buf, PAGE_SIZE, "%d\n", ext_voltage_lim);
> +}
> +
> +static ssize_t set_ec_ext_voltage_lim(struct device *dev,
> +				      struct device_attribute *attr,
> +				      const char *buf, size_t count)
> +{
> +	int ret;
> +	u16 tmp_val;
> +
> +	struct cros_ec_dev *ec = container_of(
> +			dev, struct cros_ec_dev, class_dev);
> +
> +	if (kstrtou16(buf, 0, &tmp_val) < 0)
> +		return -EINVAL;
> +
> +	ret = set_ec_ext_power_limit(ec, ext_current_lim, tmp_val);
> +	if (ret < 0)
> +		return ret;
> +
> +	ext_voltage_lim = tmp_val;
> +	if (ext_voltage_lim == EC_POWER_LIMIT_NONE)
> +		dev_info(ec->dev, "External voltage limit removed\n");
> +	else
> +		dev_info(ec->dev, "External voltage limit set to %dmV\n",
> +			 ext_voltage_lim);
> +
> +	return count;
> +}
> +
> +static DEVICE_ATTR(ext_current_lim, 0664, get_ec_ext_current_lim,
> +		   set_ec_ext_current_lim);
> +static DEVICE_ATTR(ext_voltage_lim, 0664, get_ec_ext_voltage_lim,
> +		   set_ec_ext_voltage_lim);
> +
> +static struct attribute *__ext_power_cmds_attrs[] = {
> +	&dev_attr_ext_current_lim.attr,
> +	&dev_attr_ext_voltage_lim.attr,
> +	NULL,
> +};

What do these files control? I suspect this is already covered
by a standard POWER_SUPPLY_PROP_* property.

> +struct attribute_group cros_usb_pd_charger_attr_group = {
> +	.name = "usb-pd-charger",
> +	.attrs = __ext_power_cmds_attrs,
> +};
> +EXPORT_SYMBOL(cros_usb_pd_charger_attr_group);
> +
> +static SIMPLE_DEV_PM_OPS(cros_usb_pd_charger_pm_ops,
> +	cros_usb_pd_charger_suspend, cros_usb_pd_charger_resume);
> +
> +static struct platform_driver cros_usb_pd_charger_driver = {
> +	.driver = {
> +		.name = DRV_NAME,
> +		.owner = THIS_MODULE,

Please drop .owner

> +		.pm = &cros_usb_pd_charger_pm_ops,
> +	},
> +	.probe = cros_usb_pd_charger_probe,
> +	.remove = cros_usb_pd_charger_remove,
> +};
> +
> +module_platform_driver(cros_usb_pd_charger_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("Chrome USB PD charger");
> +MODULE_ALIAS("platform:" DRV_NAME);
> diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
> index c61535979b8f..30eb9493b418 100644
> --- a/include/linux/mfd/cros_ec.h
> +++ b/include/linux/mfd/cros_ec.h
> @@ -19,6 +19,7 @@
>  #include <linux/cdev.h>
>  #include <linux/device.h>
>  #include <linux/notifier.h>
> +#include <linux/power_supply.h>
>  #include <linux/mfd/cros_ec_commands.h>
>  #include <linux/mutex.h>
>  
> @@ -143,6 +144,7 @@ struct cros_ec_device {
>  			struct cros_ec_command *msg);
>  	int (*pkt_xfer)(struct cros_ec_device *ec,
>  			struct cros_ec_command *msg);
> +	struct power_supply *charger;
>  	struct mutex lock;
>  	bool mkbp_event_supported;
>  	struct blocking_notifier_head event_notifier;
> @@ -321,6 +323,7 @@ u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);
>  extern struct attribute_group cros_ec_attr_group;
>  extern struct attribute_group cros_ec_lightbar_attr_group;
>  extern struct attribute_group cros_ec_vbc_attr_group;
> +extern struct attribute_group cros_usb_pd_charger_attr_group;
>  
>  /* debugfs stuff */
>  int cros_ec_debugfs_init(struct cros_ec_dev *ec);

-- Sebastian
Miguel Ojeda Feb. 24, 2018, 12:05 a.m. UTC | #4
On Wed, Jan 17, 2018 at 6:59 PM, Enric Balletbo i Serra
<enric.balletbo@collabora.com> wrote:
> 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>
> ---
>  drivers/power/supply/Kconfig              |  11 +
>  drivers/power/supply/Makefile             |   1 +
>  drivers/power/supply/cros_usbpd-charger.c | 953 ++++++++++++++++++++++++++++++
>  include/linux/mfd/cros_ec.h               |   3 +
>  4 files changed, 968 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..641503c1d40a 100644
> --- a/drivers/power/supply/Kconfig
> +++ b/drivers/power/supply/Kconfig
> @@ -624,4 +624,15 @@ config CHARGER_RT9455
>         help
>           Say Y to enable support for Richtek RT9455 battery charger.
>
> +config CHARGER_CROS_USB_PD
> +       tristate "Chrome OS EC based USB PD charger"
> +       depends on MFD_CROS_EC
> +       select RTC_LIB
> +       default n
> +       help
> +         Say Y here to enable Chrome OS EC based USB PD 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..c412fe8b562d 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_USB_PD)      += 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..1c48185f8163
> --- /dev/null
> +++ b/drivers/power/supply/cros_usbpd-charger.c
> @@ -0,0 +1,953 @@
> +/*
> + * Power supply driver for ChromeOS EC based USB PD Charger.
> + *
> + * Copyright (c) 2014 - 2018 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.
> + */
> +
> +#include <linux/fs.h>
> +#include <linux/ktime.h>
> +#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/rtc.h>
> +#include <linux/slab.h>
> +
> +#define CROS_USB_PD_MAX_LOG_ENTRIES    30
> +
> +#define CROS_USB_PD_LOG_UPDATE_DELAY msecs_to_jiffies(60000)
> +#define CROS_USB_PD_CACHE_UPDATE_DELAY msecs_to_jiffies(500)
> +
> +/* Buffer + macro for building PDLOG string */
> +#define BUF_SIZE 80
> +#define APPEND_STRING(buf, len, str, ...) ((len) += \
> +       snprintf((buf) + (len), max(BUF_SIZE - (len), 0), (str), ##__VA_ARGS__))
> +
> +#define CHARGER_DIR_NAME               "CROS_USB_PD_CHARGER%d"
> +#define CHARGER_DIR_NAME_LENGTH                sizeof(CHARGER_DIR_NAME)
> +#define DRV_NAME "cros-usb-pd-charger"
> +
> +#define MANUFACTURER_MODEL_LENGTH      32
> +
> +struct port_data {
> +       int port_number;
> +       char name[CHARGER_DIR_NAME_LENGTH];
> +       char manufacturer[MANUFACTURER_MODEL_LENGTH];
> +       char model_name[MANUFACTURER_MODEL_LENGTH];
> +       struct power_supply *psy;
> +       struct power_supply_desc psy_desc;
> +       int psy_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 delayed_work log_work;
> +       struct workqueue_struct *log_workqueue;
> +       struct notifier_block notifier;
> +       bool suspended;
> +};
> +
> +#define EC_MAX_IN_SIZE EC_PROTO2_MAX_REQUEST_SIZE
> +#define EC_MAX_OUT_SIZE EC_PROTO2_MAX_RESPONSE_SIZE
> +u8 ec_inbuf[EC_MAX_IN_SIZE];
> +u8 ec_outbuf[EC_MAX_OUT_SIZE];
> +
> +static enum power_supply_property cros_usb_pd_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_CHARGE_CONTROL_LIMIT_MAX,
> +       POWER_SUPPLY_PROP_MODEL_NAME,
> +       POWER_SUPPLY_PROP_MANUFACTURER,
> +};
> +
> +/* Current external voltage/current limit in mV/mA. Default to none. */
> +static u16 ext_voltage_lim = EC_POWER_LIMIT_NONE;
> +static u16 ext_current_lim = EC_POWER_LIMIT_NONE;
> +
> +static int ec_command(struct charger_data *charger, int version, int command,
> +                     u8 *outdata, int outsize, u8 *indata,
> +                     int insize)
> +{
> +       struct cros_ec_device *ec_device = charger->ec_device;
> +       struct cros_ec_dev *ec_dev = charger->ec_dev;
> +       struct cros_ec_command *msg;
> +       int ret;
> +
> +       msg = kzalloc(sizeof(*msg) + max(insize, outsize), 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(ec_device, msg);
> +       if (ret > 0 && insize)
> +               memcpy(indata, msg->data, insize);
> +
> +       kfree(msg);
> +       return ret;
> +}
> +
> +static int set_ec_usb_pd_override_ports(struct charger_data *charger,
> +                                       int port_num)
> +{
> +       struct device *dev = charger->dev;
> +       struct ec_params_charge_port_override req;
> +       int ret;
> +
> +       req.override_port = port_num;
> +
> +       ret = ec_command(charger, 0, EC_CMD_PD_CHARGE_PORT_OVERRIDE,
> +                        (u8 *)&req, sizeof(req),
> +                        NULL, 0);
> +       if (ret < 0) {
> +               dev_info(dev, "Port Override command returned 0x%x\n", ret);
> +               return -EINVAL;
> +       }
> +
> +       return 0;
> +}
> +
> +static int get_ec_num_ports(struct charger_data *charger, int *num_ports)
> +{
> +       struct device *dev = charger->dev;
> +       struct ec_response_usb_pd_ports *resp =
> +           (struct ec_response_usb_pd_ports *)ec_inbuf;
> +       int ret;
> +
> +       *num_ports = 0;
> +       ret = ec_command(charger, 0, EC_CMD_USB_PD_PORTS,
> +                        NULL, 0, ec_inbuf, EC_MAX_IN_SIZE);
> +       if (ret < 0) {
> +               dev_err(dev, "Unable to query PD ports (err:0x%x)\n", ret);
> +               return ret;
> +       }
> +       *num_ports = resp->num_ports;
> +       dev_dbg(dev, "Num ports = %d\n", *num_ports);
> +
> +       return 0;
> +}
> +
> +static int get_ec_usb_pd_discovery_info(struct port_data *port)
> +{
> +       struct charger_data *charger = port->charger;
> +       struct device *dev = charger->dev;
> +       struct ec_params_usb_pd_info_request req;
> +       struct ec_params_usb_pd_discovery_entry resp;
> +       int ret;
> +
> +       req.port = port->port_number;
> +
> +       ret = ec_command(charger, 0, EC_CMD_USB_PD_DISCOVERY,
> +                        (u8 *)&req, sizeof(req),
> +                        (u8 *)&resp, sizeof(resp));
> +       if (ret < 0) {
> +               dev_err(dev, "Unable to query Discovery info (err:0x%x)\n",
> +                       ret);
> +               return -EINVAL;
> +       }
> +
> +       dev_dbg(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, MANUFACTURER_MODEL_LENGTH, "%x", resp.vid);
> +       snprintf(port->model_name, MANUFACTURER_MODEL_LENGTH, "%x", resp.pid);
> +
> +       return 0;
> +}
> +
> +static int get_ec_usb_pd_power_info(struct port_data *port)
> +{
> +       struct charger_data *charger = port->charger;
> +       struct device *dev = charger->dev;
> +       struct ec_params_usb_pd_power_info req;
> +       struct ec_response_usb_pd_power_info resp;
> +       char role_str[80];
> +       int ret, last_psy_status, last_psy_type;
> +
> +       req.port = port->port_number;
> +       ret = ec_command(charger, 0, EC_CMD_USB_PD_POWER_INFO,
> +                        (u8 *)&req, sizeof(req),
> +                        (u8 *)&resp, sizeof(resp));
> +       if (ret < 0) {
> +               dev_err(dev, "Unable to query PD power info (err:0x%x)\n", ret);
> +               return -EINVAL;
> +       }
> +
> +       last_psy_status = port->psy_status;
> +       last_psy_type = port->psy_type;
> +
> +       switch (resp.role) {
> +       case USB_PD_PORT_POWER_DISCONNECTED:
> +               snprintf(role_str, sizeof(role_str), "%s", "DISCONNECTED");
> +               port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +               port->psy_online = 0;
> +               break;
> +       case USB_PD_PORT_POWER_SOURCE:
> +               snprintf(role_str, sizeof(role_str), "%s", "SOURCE");
> +               port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +               port->psy_online = 0;
> +               break;
> +       case USB_PD_PORT_POWER_SINK:
> +               snprintf(role_str, sizeof(role_str), "%s", "SINK");
> +               port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
> +               port->psy_online = 1;
> +               break;
> +       case USB_PD_PORT_POWER_SINK_NOT_CHARGING:
> +               snprintf(role_str, sizeof(role_str), "%s", "NOT CHARGING");
> +               port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
> +               port->psy_online = 1;
> +               break;
> +       default:
> +               snprintf(role_str, sizeof(role_str), "%s", "UNKNOWN");
> +               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_type = POWER_SUPPLY_TYPE_USB;
> +               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_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
> +               else
> +                       port->psy_type = POWER_SUPPLY_TYPE_USB;
> +               break;
> +       case USB_CHG_TYPE_OTHER:
> +       case USB_CHG_TYPE_PROPRIETARY:
> +               port->psy_type = POWER_SUPPLY_TYPE_APPLE_BRICK_ID;
> +               break;
> +       case USB_CHG_TYPE_C:
> +               port->psy_type = POWER_SUPPLY_TYPE_USB_TYPE_C;
> +               break;
> +       case USB_CHG_TYPE_BC12_DCP:
> +               port->psy_type = POWER_SUPPLY_TYPE_USB_DCP;
> +               break;
> +       case USB_CHG_TYPE_BC12_CDP:
> +               port->psy_type = POWER_SUPPLY_TYPE_USB_CDP;
> +               break;
> +       case USB_CHG_TYPE_PD:
> +               if (resp.dualrole)
> +                       port->psy_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
> +               else
> +                       port->psy_type = POWER_SUPPLY_TYPE_USB_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. Treat this case as a dedicated charger since we
> +                * don't know any better just yet. Additionally since the power
> +                * capabilities are unknown, report the max current and voltage
> +                * as zero.
> +                */
> +               port->psy_type = POWER_SUPPLY_TYPE_MAINS;
> +               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_type = POWER_SUPPLY_TYPE_USB;
> +       }
> +
> +       port->psy_desc.type = port->psy_type;
> +
> +       dev_dbg(dev,
> +               "Port %d: %s type=%d=vmax=%d vnow=%d cmax=%d clim=%d pmax=%d\n",
> +               port->port_number, role_str, 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_type != port->psy_type ||
> +           last_psy_status != port->psy_status) {
> +               dev_dbg(dev, "Port %d: Calling power_supply_changed\n",
> +                       port->port_number);
> +               power_supply_changed(port->psy);
> +       }
> +
> +       return 0;
> +}
> +
> +static int get_ec_port_status(struct port_data *port, bool ratelimit)
> +{
> +       int ret;
> +
> +       if (ratelimit &&
> +           time_is_after_jiffies(port->last_update +
> +                                 CROS_USB_PD_CACHE_UPDATE_DELAY))
> +               return 0;
> +
> +       ret = get_ec_usb_pd_power_info(port);
> +       if (ret < 0)
> +               return ret;
> +
> +       ret = get_ec_usb_pd_discovery_info(port);
> +       port->last_update = jiffies;
> +
> +       return ret;
> +}
> +
> +static void cros_usb_pd_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++)
> +               get_ec_port_status(charger->ports[i], false);
> +}
> +
> +static int cros_usb_pd_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 device *dev = charger->dev;
> +       struct cros_ec_device *ec_device = charger->ec_device;
> +       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:
> +       case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +               ret = get_ec_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:
> +               /* TODO: change this to voltage_now. */
> +               val->intval = port->psy_voltage_now * 1000;
> +               break;
> +       case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +               /* TODO: send a TBD host command to the EC. */
> +               val->intval = 0;
> +               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_usb_pd_charger_set_prop(struct power_supply *psy,
> +                                   enum power_supply_property psp,
> +                                   const union power_supply_propval *val)
> +{
> +       struct port_data *port = power_supply_get_drvdata(psy);
> +       struct charger_data *charger = port->charger;
> +       int port_number;
> +
> +       switch (psp) {
> +       case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +               /*
> +                * A value of -1 implies switching to battery as the power
> +                * source. Any other value implies using this port as the
> +                * power source.
> +                */
> +               port_number = val->intval;
> +               if (port_number != -1)
> +                       port_number = port->port_number;
> +               return set_ec_usb_pd_override_ports(charger, port_number);
> +       default:
> +               return -EINVAL;
> +       }
> +       return 0;
> +}
> +
> +static int cros_usb_pd_charger_is_writeable(struct power_supply *psy,
> +               enum power_supply_property psp)
> +{
> +       int ret;
> +
> +       switch (psp) {
> +       case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
> +               ret = 1;
> +               break;
> +       default:
> +               ret = 0;
> +       }
> +
> +       return ret;
> +}
> +
> +static void cros_usb_pd_print_log_entry(struct ec_response_pd_log *r,
> +                                       ktime_t tstamp)
> +{
> +       static const char * const fault_names[] = {
> +               "---", "OCP", "fast OCP", "OVP", "Discharge"
> +       };
> +       static const char * const role_names[] = {
> +               "Disconnected", "SRC", "SNK", "SNK (not charging)"
> +       };
> +       static const char * const chg_type_names[] = {
> +               "None", "PD", "Type-C", "Proprietary",
> +               "DCP", "CDP", "SDP", "Other", "VBUS"
> +       };
> +       int i;
> +       int role_idx, type_idx;
> +       const char *fault, *role, *chg_type;
> +       struct usb_chg_measures *meas;
> +       struct mcdp_info *minfo;
> +       struct rtc_time rt;
> +       u64 msecs;
> +       int len = 0;
> +       char buf[BUF_SIZE + 1];
> +
> +       /* the timestamp is the number of 1024th of seconds in the past */
> +       tstamp = ktime_sub_us(tstamp,
> +                (u64)r->timestamp << PD_LOG_TIMESTAMP_SHIFT);
> +       rt = rtc_ktime_to_tm(tstamp);
> +
> +       switch (r->type) {
> +       case PD_EVENT_MCU_CHARGE:
> +               if (r->data & CHARGE_FLAGS_OVERRIDE)
> +                       APPEND_STRING(buf, len, "override ");
> +               if (r->data & CHARGE_FLAGS_DELAYED_OVERRIDE)
> +                       APPEND_STRING(buf, len, "pending_override ");
> +               role_idx = r->data & CHARGE_FLAGS_ROLE_MASK;
> +               role = role_idx < ARRAY_SIZE(role_names) ?
> +                       role_names[role_idx] : "Unknown";
> +               type_idx = (r->data & CHARGE_FLAGS_TYPE_MASK)
> +                        >> CHARGE_FLAGS_TYPE_SHIFT;
> +               chg_type = type_idx < ARRAY_SIZE(chg_type_names) ?
> +                       chg_type_names[type_idx] : "???";
> +               meas = (struct usb_chg_measures *)r->payload;
> +
> +               if ((role_idx == USB_PD_PORT_POWER_DISCONNECTED) ||
> +                   (role_idx == USB_PD_PORT_POWER_SOURCE)) {
> +                       APPEND_STRING(buf, len, "%s", role);
> +
> +                       if ((role_idx == USB_PD_PORT_POWER_SOURCE) &&
> +                           (meas->current_max))
> +                               APPEND_STRING(buf, len, " %dmA",
> +                                             meas->current_max);
> +
> +                       break;
> +               }
> +
> +               APPEND_STRING(buf, len, "%s %s %s %dmV max %dmV / %dmA", role,
> +                       r->data & CHARGE_FLAGS_DUAL_ROLE ? "DRP" : "Charger",
> +                       chg_type,
> +                       meas->voltage_now,
> +                       meas->voltage_max,
> +                       meas->current_max);
> +               break;
> +       case PD_EVENT_ACC_RW_FAIL:
> +               APPEND_STRING(buf, len, "RW signature check failed");
> +               break;
> +       case PD_EVENT_PS_FAULT:
> +               fault = r->data < ARRAY_SIZE(fault_names) ? fault_names[r->data]
> +                                                         : "???";
> +               APPEND_STRING(buf, len, "Power supply fault: %s", fault);
> +               break;
> +       case PD_EVENT_VIDEO_DP_MODE:
> +               APPEND_STRING(buf, len, "DP mode %sabled",
> +                             (r->data == 1) ? "en" : "dis");
> +               break;
> +       case PD_EVENT_VIDEO_CODEC:
> +               minfo = (struct mcdp_info *)r->payload;
> +               APPEND_STRING(buf, len,
> +                             "HDMI info: family:%04x chipid:%04x "
> +                             "irom:%d.%d.%d fw:%d.%d.%d",
> +                             MCDP_FAMILY(minfo->family),
> +                             MCDP_CHIPID(minfo->chipid),
> +                             minfo->irom.major, minfo->irom.minor,
> +                             minfo->irom.build, minfo->fw.major,
> +                             minfo->fw.minor, minfo->fw.build);
> +               break;
> +       default:
> +               APPEND_STRING(buf, len,
> +                       "Event %02x (%04x) [", r->type, r->data);
> +               for (i = 0; i < PD_LOG_SIZE(r->size_port); i++)
> +                       APPEND_STRING(buf, len, "%02x ", r->payload[i]);
> +               APPEND_STRING(buf, len, "]");
> +               break;
> +       }
> +
> +       msecs = ktime_to_ms(tstamp);
> +       do_div(msecs, MSEC_PER_SEC);
> +       pr_info("PDLOG %d/%02d/%02d %02d:%02d:%02d.%03lld P%d %s\n",
> +               rt.tm_year + 1900, rt.tm_mon + 1, rt.tm_mday,
> +               rt.tm_hour, rt.tm_min, rt.tm_sec, msecs,
> +               PD_LOG_PORT(r->size_port), buf);
> +}
> +
> +static void cros_usb_pd_log_check(struct work_struct *work)
> +{
> +       struct charger_data *charger = container_of(to_delayed_work(work),
> +               struct charger_data, log_work);
> +       struct device *dev = charger->dev;
> +       union {
> +               struct ec_response_pd_log r;
> +               u32 words[8]; /* space for the payload */
> +       } u;
> +       int ret;
> +       int entries = 0;
> +       ktime_t now;
> +
> +       if (charger->suspended) {
> +               dev_dbg(dev, "Suspended...bailing out\n");
> +               return;
> +       }
> +
> +       while (entries++ < CROS_USB_PD_MAX_LOG_ENTRIES) {
> +               ret = ec_command(charger, 0, EC_CMD_PD_GET_LOG_ENTRY,
> +                                NULL, 0, (u8 *)&u, sizeof(u));
> +               now = ktime_get_real();
> +               if (ret < 0) {
> +                       dev_dbg(dev, "Cannot get PD log %d\n", ret);
> +                       break;
> +               }
> +               if (u.r.type == PD_EVENT_NO_ENTRY)
> +                       break;
> +
> +               cros_usb_pd_print_log_entry(&u.r, now);
> +       }
> +
> +       queue_delayed_work(charger->log_workqueue, &charger->log_work,
> +               CROS_USB_PD_LOG_UPDATE_DELAY);
> +}
> +
> +static int cros_usb_pd_ec_event(struct notifier_block *nb,
> +       unsigned long queued_during_suspend, void *_notify)
> +{
> +       struct charger_data *charger;
> +       struct device *dev;
> +       struct cros_ec_device *ec_device;
> +       u32 host_event;
> +
> +       charger = container_of(nb, struct charger_data, notifier);
> +       dev = charger->dev;
> +       ec_device = charger->ec_device;
> +
> +       host_event = cros_ec_get_host_event(ec_device);
> +       if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
> +               cros_usb_pd_charger_power_changed(charger->ports[0]->psy);
> +               return NOTIFY_OK;
> +       } else {
> +               return NOTIFY_DONE;
> +       }
> +}
> +
> +static char *charger_supplied_to[] = {"cros-usb_pd-charger"};
> +
> +static int cros_usb_pd_charger_probe(struct platform_device *pd)
> +{
> +       struct device *dev = &pd->dev;
> +       struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
> +       struct cros_ec_device *ec_device;
> +       struct charger_data *charger;
> +       struct port_data *port;
> +       struct power_supply_desc *psy_desc;
> +       struct power_supply *psy;
> +       int i;
> +       int ret = -EINVAL;
> +
> +       if (!ec_dev) {
> +               dev_err(dev, "No EC dev found\n");
> +               return -EINVAL;
> +       }
> +
> +       ec_device = ec_dev->ec_dev;
> +       if (!ec_device) {
> +               dev_err(dev, "No EC device found.\n");
> +               return -EINVAL;
> +       }
> +
> +       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);
> +
> +       if ((get_ec_num_ports(charger, &charger->num_charger_ports) < 0) ||
> +           !charger->num_charger_ports) {
> +               /*
> +                * 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_usb_pd_charger_get_prop;
> +               psy_desc->set_property = cros_usb_pd_charger_set_prop;
> +               psy_desc->property_is_writeable =
> +                                       cros_usb_pd_charger_is_writeable;
> +               psy_desc->external_power_changed =
> +                                       cros_usb_pd_charger_power_changed;
> +               psy_desc->properties = cros_usb_pd_charger_props;
> +               psy_desc->num_properties =
> +                                       ARRAY_SIZE(cros_usb_pd_charger_props);
> +
> +               psy_cfg.drv_data = port;
> +               psy_cfg.supplied_to = charger_supplied_to;
> +               psy_cfg.num_supplicants = ARRAY_SIZE(charger_supplied_to);
> +
> +               psy = 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;
> +               ec_device->charger = psy;
> +       }
> +
> +       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_usb_pd_ec_event;
> +               ret = blocking_notifier_chain_register(
> +                                               &ec_device->event_notifier,
> +                                               &charger->notifier);
> +               if (ret < 0)
> +                       dev_warn(dev, "failed to register notifier\n");
> +       }
> +
> +       /* Retrieve PD event logs periodically */
> +       INIT_DELAYED_WORK(&charger->log_work, cros_usb_pd_log_check);
> +       charger->log_workqueue =
> +               create_singlethread_workqueue("cros_usb_pd_log");

One more thing, assuming you are going to send a v2 at some point:
please avoid using create*workqueue() functions, they are deprecated.

Cheers,
Miguel

> +       queue_delayed_work(charger->log_workqueue, &charger->log_work,
> +               CROS_USB_PD_LOG_UPDATE_DELAY);
> +
> +       return 0;
> +
> +fail:
> +       WARN(1, "%s: Failing probe (err:0x%x)\n", dev_name(dev), ret);
> +
> +fail_nowarn:
> +       if (charger) {
> +               ec_device->charger = NULL;
> +               for (i = 0; i < charger->num_registered_psy; i++) {
> +                       port = charger->ports[i];
> +                       power_supply_unregister(port->psy);
> +                       devm_kfree(dev, port);
> +               }
> +               platform_set_drvdata(pd, NULL);
> +               devm_kfree(dev, charger);
> +       }
> +
> +       dev_info(dev, "Failing probe (err:0x%x)\n", ret);
> +       return ret;
> +}
> +
> +static int cros_usb_pd_charger_remove(struct platform_device *pd)
> +{
> +       struct charger_data *charger = platform_get_drvdata(pd);
> +       struct cros_ec_device *ec_device = charger->ec_device;
> +       struct device *dev = charger->dev;
> +       struct port_data *port;
> +       int i;
> +
> +       if (charger) {
> +               ec_device->charger = NULL;
> +               for (i = 0; i < charger->num_registered_psy; i++) {
> +                       port = charger->ports[i];
> +                       power_supply_unregister(port->psy);
> +                       devm_kfree(dev, port);
> +               }
> +               flush_delayed_work(&charger->log_work);
> +               platform_set_drvdata(pd, NULL);
> +               devm_kfree(dev, charger);
> +       }
> +       return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int cros_usb_pd_charger_resume(struct device *dev)
> +{
> +       struct charger_data *charger = dev_get_drvdata(dev);
> +       int i;
> +
> +       if (!charger)
> +               return 0;
> +
> +       charger->suspended = false;
> +
> +       for (i = 0; i < charger->num_registered_psy; i++) {
> +               power_supply_changed(charger->ports[i]->psy);
> +               charger->ports[i]->last_update =
> +                               jiffies - CROS_USB_PD_CACHE_UPDATE_DELAY;
> +       }
> +       queue_delayed_work(charger->log_workqueue, &charger->log_work,
> +               CROS_USB_PD_LOG_UPDATE_DELAY);
> +
> +       return 0;
> +}
> +
> +static int cros_usb_pd_charger_suspend(struct device *dev)
> +{
> +       struct charger_data *charger = dev_get_drvdata(dev);
> +
> +       charger->suspended = true;
> +
> +       if (charger)
> +               flush_delayed_work(&charger->log_work);
> +       return 0;
> +}
> +#endif
> +
> +static int set_ec_ext_power_limit(struct cros_ec_dev *ec,
> +                                 u16 current_lim, u16 voltage_lim)
> +{
> +       struct ec_params_external_power_limit_v1 *req;
> +       struct cros_ec_command *msg;
> +       int ret;
> +
> +       msg = kzalloc(sizeof(*msg) + sizeof(*req), GFP_KERNEL);
> +       if (!msg)
> +               return -ENOMEM;
> +
> +       req = (struct ec_params_external_power_limit_v1 *)msg->data;
> +
> +       req->current_lim = current_lim;
> +       req->voltage_lim = voltage_lim;
> +
> +       msg->version = 1;
> +       msg->command = ec->cmd_offset + EC_CMD_EXTERNAL_POWER_LIMIT;
> +       msg->outsize = sizeof(*req);
> +
> +       ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
> +       if (ret < 0) {
> +               dev_warn(ec->dev,
> +                        "External power limit command returned 0x%x\n",
> +                        ret);
> +               ret = -EINVAL;
> +       } else {
> +               ret = 0;
> +       }
> +
> +       kfree(msg);
> +       return ret;
> +}
> +
> +static ssize_t get_ec_ext_current_lim(struct device *dev,
> +                                     struct device_attribute *attr,
> +                                     char *buf)
> +{
> +       return scnprintf(buf, PAGE_SIZE, "%d\n", ext_current_lim);
> +}
> +
> +static ssize_t set_ec_ext_current_lim(struct device *dev,
> +                                     struct device_attribute *attr,
> +                                     const char *buf, size_t count)
> +{
> +       int ret;
> +       u16 tmp_val;
> +       struct cros_ec_dev *ec = container_of(
> +                       dev, struct cros_ec_dev, class_dev);
> +
> +       if (kstrtou16(buf, 0, &tmp_val) < 0)
> +               return -EINVAL;
> +
> +       ret = set_ec_ext_power_limit(ec, tmp_val, ext_voltage_lim);
> +       if (ret < 0)
> +               return ret;
> +
> +       ext_current_lim = tmp_val;
> +       if (ext_current_lim == EC_POWER_LIMIT_NONE)
> +               dev_info(ec->dev, "External current limit removed\n");
> +       else
> +               dev_info(ec->dev, "External current limit set to %dmA\n",
> +                        ext_current_lim);
> +
> +       return count;
> +}
> +
> +static ssize_t get_ec_ext_voltage_lim(struct device *dev,
> +                                     struct device_attribute *attr,
> +                                     char *buf)
> +{
> +       return scnprintf(buf, PAGE_SIZE, "%d\n", ext_voltage_lim);
> +}
> +
> +static ssize_t set_ec_ext_voltage_lim(struct device *dev,
> +                                     struct device_attribute *attr,
> +                                     const char *buf, size_t count)
> +{
> +       int ret;
> +       u16 tmp_val;
> +
> +       struct cros_ec_dev *ec = container_of(
> +                       dev, struct cros_ec_dev, class_dev);
> +
> +       if (kstrtou16(buf, 0, &tmp_val) < 0)
> +               return -EINVAL;
> +
> +       ret = set_ec_ext_power_limit(ec, ext_current_lim, tmp_val);
> +       if (ret < 0)
> +               return ret;
> +
> +       ext_voltage_lim = tmp_val;
> +       if (ext_voltage_lim == EC_POWER_LIMIT_NONE)
> +               dev_info(ec->dev, "External voltage limit removed\n");
> +       else
> +               dev_info(ec->dev, "External voltage limit set to %dmV\n",
> +                        ext_voltage_lim);
> +
> +       return count;
> +}
> +
> +static DEVICE_ATTR(ext_current_lim, 0664, get_ec_ext_current_lim,
> +                  set_ec_ext_current_lim);
> +static DEVICE_ATTR(ext_voltage_lim, 0664, get_ec_ext_voltage_lim,
> +                  set_ec_ext_voltage_lim);
> +
> +static struct attribute *__ext_power_cmds_attrs[] = {
> +       &dev_attr_ext_current_lim.attr,
> +       &dev_attr_ext_voltage_lim.attr,
> +       NULL,
> +};
> +
> +struct attribute_group cros_usb_pd_charger_attr_group = {
> +       .name = "usb-pd-charger",
> +       .attrs = __ext_power_cmds_attrs,
> +};
> +EXPORT_SYMBOL(cros_usb_pd_charger_attr_group);
> +
> +static SIMPLE_DEV_PM_OPS(cros_usb_pd_charger_pm_ops,
> +       cros_usb_pd_charger_suspend, cros_usb_pd_charger_resume);
> +
> +static struct platform_driver cros_usb_pd_charger_driver = {
> +       .driver = {
> +               .name = DRV_NAME,
> +               .owner = THIS_MODULE,
> +               .pm = &cros_usb_pd_charger_pm_ops,
> +       },
> +       .probe = cros_usb_pd_charger_probe,
> +       .remove = cros_usb_pd_charger_remove,
> +};
> +
> +module_platform_driver(cros_usb_pd_charger_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("Chrome USB PD charger");
> +MODULE_ALIAS("platform:" DRV_NAME);
> diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
> index c61535979b8f..30eb9493b418 100644
> --- a/include/linux/mfd/cros_ec.h
> +++ b/include/linux/mfd/cros_ec.h
> @@ -19,6 +19,7 @@
>  #include <linux/cdev.h>
>  #include <linux/device.h>
>  #include <linux/notifier.h>
> +#include <linux/power_supply.h>
>  #include <linux/mfd/cros_ec_commands.h>
>  #include <linux/mutex.h>
>
> @@ -143,6 +144,7 @@ struct cros_ec_device {
>                         struct cros_ec_command *msg);
>         int (*pkt_xfer)(struct cros_ec_device *ec,
>                         struct cros_ec_command *msg);
> +       struct power_supply *charger;
>         struct mutex lock;
>         bool mkbp_event_supported;
>         struct blocking_notifier_head event_notifier;
> @@ -321,6 +323,7 @@ u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);
>  extern struct attribute_group cros_ec_attr_group;
>  extern struct attribute_group cros_ec_lightbar_attr_group;
>  extern struct attribute_group cros_ec_vbc_attr_group;
> +extern struct attribute_group cros_usb_pd_charger_attr_group;
>
>  /* debugfs stuff */
>  int cros_ec_debugfs_init(struct cros_ec_dev *ec);
> --
> 2.15.1
>
diff mbox

Patch

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 428b426842f4..641503c1d40a 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -624,4 +624,15 @@  config CHARGER_RT9455
 	help
 	  Say Y to enable support for Richtek RT9455 battery charger.
 
+config CHARGER_CROS_USB_PD
+	tristate "Chrome OS EC based USB PD charger"
+	depends on MFD_CROS_EC
+	select RTC_LIB
+	default n
+	help
+	  Say Y here to enable Chrome OS EC based USB PD 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..c412fe8b562d 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_USB_PD)	+= 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..1c48185f8163
--- /dev/null
+++ b/drivers/power/supply/cros_usbpd-charger.c
@@ -0,0 +1,953 @@ 
+/*
+ * Power supply driver for ChromeOS EC based USB PD Charger.
+ *
+ * Copyright (c) 2014 - 2018 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.
+ */
+
+#include <linux/fs.h>
+#include <linux/ktime.h>
+#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/rtc.h>
+#include <linux/slab.h>
+
+#define CROS_USB_PD_MAX_LOG_ENTRIES	30
+
+#define CROS_USB_PD_LOG_UPDATE_DELAY msecs_to_jiffies(60000)
+#define CROS_USB_PD_CACHE_UPDATE_DELAY msecs_to_jiffies(500)
+
+/* Buffer + macro for building PDLOG string */
+#define BUF_SIZE 80
+#define APPEND_STRING(buf, len, str, ...) ((len) += \
+	snprintf((buf) + (len), max(BUF_SIZE - (len), 0), (str), ##__VA_ARGS__))
+
+#define CHARGER_DIR_NAME		"CROS_USB_PD_CHARGER%d"
+#define CHARGER_DIR_NAME_LENGTH		sizeof(CHARGER_DIR_NAME)
+#define DRV_NAME "cros-usb-pd-charger"
+
+#define MANUFACTURER_MODEL_LENGTH	32
+
+struct port_data {
+	int port_number;
+	char name[CHARGER_DIR_NAME_LENGTH];
+	char manufacturer[MANUFACTURER_MODEL_LENGTH];
+	char model_name[MANUFACTURER_MODEL_LENGTH];
+	struct power_supply *psy;
+	struct power_supply_desc psy_desc;
+	int psy_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 delayed_work log_work;
+	struct workqueue_struct *log_workqueue;
+	struct notifier_block notifier;
+	bool suspended;
+};
+
+#define EC_MAX_IN_SIZE EC_PROTO2_MAX_REQUEST_SIZE
+#define EC_MAX_OUT_SIZE EC_PROTO2_MAX_RESPONSE_SIZE
+u8 ec_inbuf[EC_MAX_IN_SIZE];
+u8 ec_outbuf[EC_MAX_OUT_SIZE];
+
+static enum power_supply_property cros_usb_pd_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_CHARGE_CONTROL_LIMIT_MAX,
+	POWER_SUPPLY_PROP_MODEL_NAME,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+/* Current external voltage/current limit in mV/mA. Default to none. */
+static u16 ext_voltage_lim = EC_POWER_LIMIT_NONE;
+static u16 ext_current_lim = EC_POWER_LIMIT_NONE;
+
+static int ec_command(struct charger_data *charger, int version, int command,
+		      u8 *outdata, int outsize, u8 *indata,
+		      int insize)
+{
+	struct cros_ec_device *ec_device = charger->ec_device;
+	struct cros_ec_dev *ec_dev = charger->ec_dev;
+	struct cros_ec_command *msg;
+	int ret;
+
+	msg = kzalloc(sizeof(*msg) + max(insize, outsize), 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(ec_device, msg);
+	if (ret > 0 && insize)
+		memcpy(indata, msg->data, insize);
+
+	kfree(msg);
+	return ret;
+}
+
+static int set_ec_usb_pd_override_ports(struct charger_data *charger,
+					int port_num)
+{
+	struct device *dev = charger->dev;
+	struct ec_params_charge_port_override req;
+	int ret;
+
+	req.override_port = port_num;
+
+	ret = ec_command(charger, 0, EC_CMD_PD_CHARGE_PORT_OVERRIDE,
+			 (u8 *)&req, sizeof(req),
+			 NULL, 0);
+	if (ret < 0) {
+		dev_info(dev, "Port Override command returned 0x%x\n", ret);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int get_ec_num_ports(struct charger_data *charger, int *num_ports)
+{
+	struct device *dev = charger->dev;
+	struct ec_response_usb_pd_ports *resp =
+	    (struct ec_response_usb_pd_ports *)ec_inbuf;
+	int ret;
+
+	*num_ports = 0;
+	ret = ec_command(charger, 0, EC_CMD_USB_PD_PORTS,
+			 NULL, 0, ec_inbuf, EC_MAX_IN_SIZE);
+	if (ret < 0) {
+		dev_err(dev, "Unable to query PD ports (err:0x%x)\n", ret);
+		return ret;
+	}
+	*num_ports = resp->num_ports;
+	dev_dbg(dev, "Num ports = %d\n", *num_ports);
+
+	return 0;
+}
+
+static int get_ec_usb_pd_discovery_info(struct port_data *port)
+{
+	struct charger_data *charger = port->charger;
+	struct device *dev = charger->dev;
+	struct ec_params_usb_pd_info_request req;
+	struct ec_params_usb_pd_discovery_entry resp;
+	int ret;
+
+	req.port = port->port_number;
+
+	ret = ec_command(charger, 0, EC_CMD_USB_PD_DISCOVERY,
+			 (u8 *)&req, sizeof(req),
+			 (u8 *)&resp, sizeof(resp));
+	if (ret < 0) {
+		dev_err(dev, "Unable to query Discovery info (err:0x%x)\n",
+			ret);
+		return -EINVAL;
+	}
+
+	dev_dbg(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, MANUFACTURER_MODEL_LENGTH, "%x", resp.vid);
+	snprintf(port->model_name, MANUFACTURER_MODEL_LENGTH, "%x", resp.pid);
+
+	return 0;
+}
+
+static int get_ec_usb_pd_power_info(struct port_data *port)
+{
+	struct charger_data *charger = port->charger;
+	struct device *dev = charger->dev;
+	struct ec_params_usb_pd_power_info req;
+	struct ec_response_usb_pd_power_info resp;
+	char role_str[80];
+	int ret, last_psy_status, last_psy_type;
+
+	req.port = port->port_number;
+	ret = ec_command(charger, 0, EC_CMD_USB_PD_POWER_INFO,
+			 (u8 *)&req, sizeof(req),
+			 (u8 *)&resp, sizeof(resp));
+	if (ret < 0) {
+		dev_err(dev, "Unable to query PD power info (err:0x%x)\n", ret);
+		return -EINVAL;
+	}
+
+	last_psy_status = port->psy_status;
+	last_psy_type = port->psy_type;
+
+	switch (resp.role) {
+	case USB_PD_PORT_POWER_DISCONNECTED:
+		snprintf(role_str, sizeof(role_str), "%s", "DISCONNECTED");
+		port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		port->psy_online = 0;
+		break;
+	case USB_PD_PORT_POWER_SOURCE:
+		snprintf(role_str, sizeof(role_str), "%s", "SOURCE");
+		port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		port->psy_online = 0;
+		break;
+	case USB_PD_PORT_POWER_SINK:
+		snprintf(role_str, sizeof(role_str), "%s", "SINK");
+		port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
+		port->psy_online = 1;
+		break;
+	case USB_PD_PORT_POWER_SINK_NOT_CHARGING:
+		snprintf(role_str, sizeof(role_str), "%s", "NOT CHARGING");
+		port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		port->psy_online = 1;
+		break;
+	default:
+		snprintf(role_str, sizeof(role_str), "%s", "UNKNOWN");
+		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_type = POWER_SUPPLY_TYPE_USB;
+		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_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
+		else
+			port->psy_type = POWER_SUPPLY_TYPE_USB;
+		break;
+	case USB_CHG_TYPE_OTHER:
+	case USB_CHG_TYPE_PROPRIETARY:
+		port->psy_type = POWER_SUPPLY_TYPE_APPLE_BRICK_ID;
+		break;
+	case USB_CHG_TYPE_C:
+		port->psy_type = POWER_SUPPLY_TYPE_USB_TYPE_C;
+		break;
+	case USB_CHG_TYPE_BC12_DCP:
+		port->psy_type = POWER_SUPPLY_TYPE_USB_DCP;
+		break;
+	case USB_CHG_TYPE_BC12_CDP:
+		port->psy_type = POWER_SUPPLY_TYPE_USB_CDP;
+		break;
+	case USB_CHG_TYPE_PD:
+		if (resp.dualrole)
+			port->psy_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
+		else
+			port->psy_type = POWER_SUPPLY_TYPE_USB_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. Treat this case as a dedicated charger since we
+		 * don't know any better just yet. Additionally since the power
+		 * capabilities are unknown, report the max current and voltage
+		 * as zero.
+		 */
+		port->psy_type = POWER_SUPPLY_TYPE_MAINS;
+		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_type = POWER_SUPPLY_TYPE_USB;
+	}
+
+	port->psy_desc.type = port->psy_type;
+
+	dev_dbg(dev,
+		"Port %d: %s type=%d=vmax=%d vnow=%d cmax=%d clim=%d pmax=%d\n",
+		port->port_number, role_str, 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_type != port->psy_type ||
+	    last_psy_status != port->psy_status) {
+		dev_dbg(dev, "Port %d: Calling power_supply_changed\n",
+			port->port_number);
+		power_supply_changed(port->psy);
+	}
+
+	return 0;
+}
+
+static int get_ec_port_status(struct port_data *port, bool ratelimit)
+{
+	int ret;
+
+	if (ratelimit &&
+	    time_is_after_jiffies(port->last_update +
+				  CROS_USB_PD_CACHE_UPDATE_DELAY))
+		return 0;
+
+	ret = get_ec_usb_pd_power_info(port);
+	if (ret < 0)
+		return ret;
+
+	ret = get_ec_usb_pd_discovery_info(port);
+	port->last_update = jiffies;
+
+	return ret;
+}
+
+static void cros_usb_pd_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++)
+		get_ec_port_status(charger->ports[i], false);
+}
+
+static int cros_usb_pd_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 device *dev = charger->dev;
+	struct cros_ec_device *ec_device = charger->ec_device;
+	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:
+	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+		ret = get_ec_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:
+		/* TODO: change this to voltage_now. */
+		val->intval = port->psy_voltage_now * 1000;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+		/* TODO: send a TBD host command to the EC. */
+		val->intval = 0;
+		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_usb_pd_charger_set_prop(struct power_supply *psy,
+				    enum power_supply_property psp,
+				    const union power_supply_propval *val)
+{
+	struct port_data *port = power_supply_get_drvdata(psy);
+	struct charger_data *charger = port->charger;
+	int port_number;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+		/*
+		 * A value of -1 implies switching to battery as the power
+		 * source. Any other value implies using this port as the
+		 * power source.
+		 */
+		port_number = val->intval;
+		if (port_number != -1)
+			port_number = port->port_number;
+		return set_ec_usb_pd_override_ports(charger, port_number);
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int cros_usb_pd_charger_is_writeable(struct power_supply *psy,
+		enum power_supply_property psp)
+{
+	int ret;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+		ret = 1;
+		break;
+	default:
+		ret = 0;
+	}
+
+	return ret;
+}
+
+static void cros_usb_pd_print_log_entry(struct ec_response_pd_log *r,
+					ktime_t tstamp)
+{
+	static const char * const fault_names[] = {
+		"---", "OCP", "fast OCP", "OVP", "Discharge"
+	};
+	static const char * const role_names[] = {
+		"Disconnected", "SRC", "SNK", "SNK (not charging)"
+	};
+	static const char * const chg_type_names[] = {
+		"None", "PD", "Type-C", "Proprietary",
+		"DCP", "CDP", "SDP", "Other", "VBUS"
+	};
+	int i;
+	int role_idx, type_idx;
+	const char *fault, *role, *chg_type;
+	struct usb_chg_measures *meas;
+	struct mcdp_info *minfo;
+	struct rtc_time rt;
+	u64 msecs;
+	int len = 0;
+	char buf[BUF_SIZE + 1];
+
+	/* the timestamp is the number of 1024th of seconds in the past */
+	tstamp = ktime_sub_us(tstamp,
+		 (u64)r->timestamp << PD_LOG_TIMESTAMP_SHIFT);
+	rt = rtc_ktime_to_tm(tstamp);
+
+	switch (r->type) {
+	case PD_EVENT_MCU_CHARGE:
+		if (r->data & CHARGE_FLAGS_OVERRIDE)
+			APPEND_STRING(buf, len, "override ");
+		if (r->data & CHARGE_FLAGS_DELAYED_OVERRIDE)
+			APPEND_STRING(buf, len, "pending_override ");
+		role_idx = r->data & CHARGE_FLAGS_ROLE_MASK;
+		role = role_idx < ARRAY_SIZE(role_names) ?
+			role_names[role_idx] : "Unknown";
+		type_idx = (r->data & CHARGE_FLAGS_TYPE_MASK)
+			 >> CHARGE_FLAGS_TYPE_SHIFT;
+		chg_type = type_idx < ARRAY_SIZE(chg_type_names) ?
+			chg_type_names[type_idx] : "???";
+		meas = (struct usb_chg_measures *)r->payload;
+
+		if ((role_idx == USB_PD_PORT_POWER_DISCONNECTED) ||
+		    (role_idx == USB_PD_PORT_POWER_SOURCE)) {
+			APPEND_STRING(buf, len, "%s", role);
+
+			if ((role_idx == USB_PD_PORT_POWER_SOURCE) &&
+			    (meas->current_max))
+				APPEND_STRING(buf, len, " %dmA",
+					      meas->current_max);
+
+			break;
+		}
+
+		APPEND_STRING(buf, len, "%s %s %s %dmV max %dmV / %dmA", role,
+			r->data & CHARGE_FLAGS_DUAL_ROLE ? "DRP" : "Charger",
+			chg_type,
+			meas->voltage_now,
+			meas->voltage_max,
+			meas->current_max);
+		break;
+	case PD_EVENT_ACC_RW_FAIL:
+		APPEND_STRING(buf, len, "RW signature check failed");
+		break;
+	case PD_EVENT_PS_FAULT:
+		fault = r->data < ARRAY_SIZE(fault_names) ? fault_names[r->data]
+							  : "???";
+		APPEND_STRING(buf, len, "Power supply fault: %s", fault);
+		break;
+	case PD_EVENT_VIDEO_DP_MODE:
+		APPEND_STRING(buf, len, "DP mode %sabled",
+			      (r->data == 1) ? "en" : "dis");
+		break;
+	case PD_EVENT_VIDEO_CODEC:
+		minfo = (struct mcdp_info *)r->payload;
+		APPEND_STRING(buf, len,
+			      "HDMI info: family:%04x chipid:%04x "
+			      "irom:%d.%d.%d fw:%d.%d.%d",
+			      MCDP_FAMILY(minfo->family),
+			      MCDP_CHIPID(minfo->chipid),
+			      minfo->irom.major, minfo->irom.minor,
+			      minfo->irom.build, minfo->fw.major,
+			      minfo->fw.minor, minfo->fw.build);
+		break;
+	default:
+		APPEND_STRING(buf, len,
+			"Event %02x (%04x) [", r->type, r->data);
+		for (i = 0; i < PD_LOG_SIZE(r->size_port); i++)
+			APPEND_STRING(buf, len, "%02x ", r->payload[i]);
+		APPEND_STRING(buf, len, "]");
+		break;
+	}
+
+	msecs = ktime_to_ms(tstamp);
+	do_div(msecs, MSEC_PER_SEC);
+	pr_info("PDLOG %d/%02d/%02d %02d:%02d:%02d.%03lld P%d %s\n",
+		rt.tm_year + 1900, rt.tm_mon + 1, rt.tm_mday,
+		rt.tm_hour, rt.tm_min, rt.tm_sec, msecs,
+		PD_LOG_PORT(r->size_port), buf);
+}
+
+static void cros_usb_pd_log_check(struct work_struct *work)
+{
+	struct charger_data *charger = container_of(to_delayed_work(work),
+		struct charger_data, log_work);
+	struct device *dev = charger->dev;
+	union {
+		struct ec_response_pd_log r;
+		u32 words[8]; /* space for the payload */
+	} u;
+	int ret;
+	int entries = 0;
+	ktime_t now;
+
+	if (charger->suspended) {
+		dev_dbg(dev, "Suspended...bailing out\n");
+		return;
+	}
+
+	while (entries++ < CROS_USB_PD_MAX_LOG_ENTRIES) {
+		ret = ec_command(charger, 0, EC_CMD_PD_GET_LOG_ENTRY,
+				 NULL, 0, (u8 *)&u, sizeof(u));
+		now = ktime_get_real();
+		if (ret < 0) {
+			dev_dbg(dev, "Cannot get PD log %d\n", ret);
+			break;
+		}
+		if (u.r.type == PD_EVENT_NO_ENTRY)
+			break;
+
+		cros_usb_pd_print_log_entry(&u.r, now);
+	}
+
+	queue_delayed_work(charger->log_workqueue, &charger->log_work,
+		CROS_USB_PD_LOG_UPDATE_DELAY);
+}
+
+static int cros_usb_pd_ec_event(struct notifier_block *nb,
+	unsigned long queued_during_suspend, void *_notify)
+{
+	struct charger_data *charger;
+	struct device *dev;
+	struct cros_ec_device *ec_device;
+	u32 host_event;
+
+	charger = container_of(nb, struct charger_data, notifier);
+	dev = charger->dev;
+	ec_device = charger->ec_device;
+
+	host_event = cros_ec_get_host_event(ec_device);
+	if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
+		cros_usb_pd_charger_power_changed(charger->ports[0]->psy);
+		return NOTIFY_OK;
+	} else {
+		return NOTIFY_DONE;
+	}
+}
+
+static char *charger_supplied_to[] = {"cros-usb_pd-charger"};
+
+static int cros_usb_pd_charger_probe(struct platform_device *pd)
+{
+	struct device *dev = &pd->dev;
+	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+	struct cros_ec_device *ec_device;
+	struct charger_data *charger;
+	struct port_data *port;
+	struct power_supply_desc *psy_desc;
+	struct power_supply *psy;
+	int i;
+	int ret = -EINVAL;
+
+	if (!ec_dev) {
+		dev_err(dev, "No EC dev found\n");
+		return -EINVAL;
+	}
+
+	ec_device = ec_dev->ec_dev;
+	if (!ec_device) {
+		dev_err(dev, "No EC device found.\n");
+		return -EINVAL;
+	}
+
+	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);
+
+	if ((get_ec_num_ports(charger, &charger->num_charger_ports) < 0) ||
+	    !charger->num_charger_ports) {
+		/*
+		 * 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_usb_pd_charger_get_prop;
+		psy_desc->set_property = cros_usb_pd_charger_set_prop;
+		psy_desc->property_is_writeable =
+					cros_usb_pd_charger_is_writeable;
+		psy_desc->external_power_changed =
+					cros_usb_pd_charger_power_changed;
+		psy_desc->properties = cros_usb_pd_charger_props;
+		psy_desc->num_properties =
+					ARRAY_SIZE(cros_usb_pd_charger_props);
+
+		psy_cfg.drv_data = port;
+		psy_cfg.supplied_to = charger_supplied_to;
+		psy_cfg.num_supplicants = ARRAY_SIZE(charger_supplied_to);
+
+		psy = 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;
+		ec_device->charger = psy;
+	}
+
+	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_usb_pd_ec_event;
+		ret = blocking_notifier_chain_register(
+						&ec_device->event_notifier,
+						&charger->notifier);
+		if (ret < 0)
+			dev_warn(dev, "failed to register notifier\n");
+	}
+
+	/* Retrieve PD event logs periodically */
+	INIT_DELAYED_WORK(&charger->log_work, cros_usb_pd_log_check);
+	charger->log_workqueue =
+		create_singlethread_workqueue("cros_usb_pd_log");
+	queue_delayed_work(charger->log_workqueue, &charger->log_work,
+		CROS_USB_PD_LOG_UPDATE_DELAY);
+
+	return 0;
+
+fail:
+	WARN(1, "%s: Failing probe (err:0x%x)\n", dev_name(dev), ret);
+
+fail_nowarn:
+	if (charger) {
+		ec_device->charger = NULL;
+		for (i = 0; i < charger->num_registered_psy; i++) {
+			port = charger->ports[i];
+			power_supply_unregister(port->psy);
+			devm_kfree(dev, port);
+		}
+		platform_set_drvdata(pd, NULL);
+		devm_kfree(dev, charger);
+	}
+
+	dev_info(dev, "Failing probe (err:0x%x)\n", ret);
+	return ret;
+}
+
+static int cros_usb_pd_charger_remove(struct platform_device *pd)
+{
+	struct charger_data *charger = platform_get_drvdata(pd);
+	struct cros_ec_device *ec_device = charger->ec_device;
+	struct device *dev = charger->dev;
+	struct port_data *port;
+	int i;
+
+	if (charger) {
+		ec_device->charger = NULL;
+		for (i = 0; i < charger->num_registered_psy; i++) {
+			port = charger->ports[i];
+			power_supply_unregister(port->psy);
+			devm_kfree(dev, port);
+		}
+		flush_delayed_work(&charger->log_work);
+		platform_set_drvdata(pd, NULL);
+		devm_kfree(dev, charger);
+	}
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cros_usb_pd_charger_resume(struct device *dev)
+{
+	struct charger_data *charger = dev_get_drvdata(dev);
+	int i;
+
+	if (!charger)
+		return 0;
+
+	charger->suspended = false;
+
+	for (i = 0; i < charger->num_registered_psy; i++) {
+		power_supply_changed(charger->ports[i]->psy);
+		charger->ports[i]->last_update =
+				jiffies - CROS_USB_PD_CACHE_UPDATE_DELAY;
+	}
+	queue_delayed_work(charger->log_workqueue, &charger->log_work,
+		CROS_USB_PD_LOG_UPDATE_DELAY);
+
+	return 0;
+}
+
+static int cros_usb_pd_charger_suspend(struct device *dev)
+{
+	struct charger_data *charger = dev_get_drvdata(dev);
+
+	charger->suspended = true;
+
+	if (charger)
+		flush_delayed_work(&charger->log_work);
+	return 0;
+}
+#endif
+
+static int set_ec_ext_power_limit(struct cros_ec_dev *ec,
+				  u16 current_lim, u16 voltage_lim)
+{
+	struct ec_params_external_power_limit_v1 *req;
+	struct cros_ec_command *msg;
+	int ret;
+
+	msg = kzalloc(sizeof(*msg) + sizeof(*req), GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	req = (struct ec_params_external_power_limit_v1 *)msg->data;
+
+	req->current_lim = current_lim;
+	req->voltage_lim = voltage_lim;
+
+	msg->version = 1;
+	msg->command = ec->cmd_offset + EC_CMD_EXTERNAL_POWER_LIMIT;
+	msg->outsize = sizeof(*req);
+
+	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+	if (ret < 0) {
+		dev_warn(ec->dev,
+			 "External power limit command returned 0x%x\n",
+			 ret);
+		ret = -EINVAL;
+	} else {
+		ret = 0;
+	}
+
+	kfree(msg);
+	return ret;
+}
+
+static ssize_t get_ec_ext_current_lim(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", ext_current_lim);
+}
+
+static ssize_t set_ec_ext_current_lim(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	int ret;
+	u16 tmp_val;
+	struct cros_ec_dev *ec = container_of(
+			dev, struct cros_ec_dev, class_dev);
+
+	if (kstrtou16(buf, 0, &tmp_val) < 0)
+		return -EINVAL;
+
+	ret = set_ec_ext_power_limit(ec, tmp_val, ext_voltage_lim);
+	if (ret < 0)
+		return ret;
+
+	ext_current_lim = tmp_val;
+	if (ext_current_lim == EC_POWER_LIMIT_NONE)
+		dev_info(ec->dev, "External current limit removed\n");
+	else
+		dev_info(ec->dev, "External current limit set to %dmA\n",
+			 ext_current_lim);
+
+	return count;
+}
+
+static ssize_t get_ec_ext_voltage_lim(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", ext_voltage_lim);
+}
+
+static ssize_t set_ec_ext_voltage_lim(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	int ret;
+	u16 tmp_val;
+
+	struct cros_ec_dev *ec = container_of(
+			dev, struct cros_ec_dev, class_dev);
+
+	if (kstrtou16(buf, 0, &tmp_val) < 0)
+		return -EINVAL;
+
+	ret = set_ec_ext_power_limit(ec, ext_current_lim, tmp_val);
+	if (ret < 0)
+		return ret;
+
+	ext_voltage_lim = tmp_val;
+	if (ext_voltage_lim == EC_POWER_LIMIT_NONE)
+		dev_info(ec->dev, "External voltage limit removed\n");
+	else
+		dev_info(ec->dev, "External voltage limit set to %dmV\n",
+			 ext_voltage_lim);
+
+	return count;
+}
+
+static DEVICE_ATTR(ext_current_lim, 0664, get_ec_ext_current_lim,
+		   set_ec_ext_current_lim);
+static DEVICE_ATTR(ext_voltage_lim, 0664, get_ec_ext_voltage_lim,
+		   set_ec_ext_voltage_lim);
+
+static struct attribute *__ext_power_cmds_attrs[] = {
+	&dev_attr_ext_current_lim.attr,
+	&dev_attr_ext_voltage_lim.attr,
+	NULL,
+};
+
+struct attribute_group cros_usb_pd_charger_attr_group = {
+	.name = "usb-pd-charger",
+	.attrs = __ext_power_cmds_attrs,
+};
+EXPORT_SYMBOL(cros_usb_pd_charger_attr_group);
+
+static SIMPLE_DEV_PM_OPS(cros_usb_pd_charger_pm_ops,
+	cros_usb_pd_charger_suspend, cros_usb_pd_charger_resume);
+
+static struct platform_driver cros_usb_pd_charger_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.owner = THIS_MODULE,
+		.pm = &cros_usb_pd_charger_pm_ops,
+	},
+	.probe = cros_usb_pd_charger_probe,
+	.remove = cros_usb_pd_charger_remove,
+};
+
+module_platform_driver(cros_usb_pd_charger_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Chrome USB PD charger");
+MODULE_ALIAS("platform:" DRV_NAME);
diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
index c61535979b8f..30eb9493b418 100644
--- a/include/linux/mfd/cros_ec.h
+++ b/include/linux/mfd/cros_ec.h
@@ -19,6 +19,7 @@ 
 #include <linux/cdev.h>
 #include <linux/device.h>
 #include <linux/notifier.h>
+#include <linux/power_supply.h>
 #include <linux/mfd/cros_ec_commands.h>
 #include <linux/mutex.h>
 
@@ -143,6 +144,7 @@  struct cros_ec_device {
 			struct cros_ec_command *msg);
 	int (*pkt_xfer)(struct cros_ec_device *ec,
 			struct cros_ec_command *msg);
+	struct power_supply *charger;
 	struct mutex lock;
 	bool mkbp_event_supported;
 	struct blocking_notifier_head event_notifier;
@@ -321,6 +323,7 @@  u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);
 extern struct attribute_group cros_ec_attr_group;
 extern struct attribute_group cros_ec_lightbar_attr_group;
 extern struct attribute_group cros_ec_vbc_attr_group;
+extern struct attribute_group cros_usb_pd_charger_attr_group;
 
 /* debugfs stuff */
 int cros_ec_debugfs_init(struct cros_ec_dev *ec);