// SPDX-License-Identifier: GPL-2.0
/*
* Power supply driver for ChromeOS EC based Peripheral Device Charger.
*
* Copyright 2020 Google LLC.
*/
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
#include <linux/stringify.h>
#include <linux/types.h>
#include <linux/unaligned.h>
#define DRV_NAME "cros-ec-pchg"
#define PCHG_DIR_PREFIX "peripheral"
#define PCHG_DIR_NAME PCHG_DIR_PREFIX "%d"
#define PCHG_DIR_NAME_LENGTH \
sizeof(PCHG_DIR_PREFIX __stringify(EC_PCHG_MAX_PORTS))
#define PCHG_CACHE_UPDATE_DELAY msecs_to_jiffies(500)
struct port_data {
int port_number;
char name[PCHG_DIR_NAME_LENGTH];
struct power_supply *psy;
struct power_supply_desc psy_desc;
int psy_status;
int battery_percentage;
int charge_type;
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_registered_psy;
struct port_data *ports[EC_PCHG_MAX_PORTS];
struct notifier_block notifier;
};
static enum power_supply_property cros_pchg_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_CHARGE_TYPE,
POWER_SUPPLY_PROP_CAPACITY,
POWER_SUPPLY_PROP_SCOPE,
};
static int cros_pchg_ec_command(const struct charger_data *charger,
unsigned int version,
unsigned int command,
const void *outdata,
unsigned int outsize,
void *indata,
unsigned int insize)
{
struct cros_ec_dev *ec_dev = charger->ec_dev;
struct cros_ec_command *msg;
int ret;
msg = kzalloc(struct_size(msg, data, max(outsize, insize)), GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->version = version;
msg->command = ec_dev->cmd_offset + command;
msg->outsize = outsize;
msg->insize = insize;
if (outsize)
memcpy(msg->data, outdata, outsize);
ret = cros_ec_cmd_xfer_status(charger->ec_device, msg);
if (ret >= 0 && insize)
memcpy(indata, msg->data, insize);
kfree(msg);
return ret;
}
static const unsigned int pchg_cmd_version = 1;
static bool cros_pchg_cmd_ver_check(const struct charger_data *charger)
{
struct ec_params_get_cmd_versions_v1 req;
struct ec_response_get_cmd_versions rsp;
int ret;
req.cmd = EC_CMD_PCHG;
ret = cros_pchg_ec_command(charger, 1, EC_CMD_GET_CMD_VERSIONS,
&req, sizeof(req), &rsp, sizeof(rsp));
if (ret < 0) {
dev_warn(charger->dev,
"Unable to get versions of EC_CMD_PCHG (err:%d)\n",
ret);
return false;
}
return !!(rsp.version_mask & BIT(pchg_cmd_version));
}
static int cros_pchg_port_count(const struct charger_data *charger)
{
struct ec_response_pchg_count rsp;
int ret;
ret = cros_pchg_ec_command(charger, 0, EC_CMD_PCHG_COUNT,
NULL, 0, &rsp, sizeof(rsp));
if (ret < 0) {
dev_warn(charger->dev,
"Unable to get number or ports (err:%d)\n", ret);
return ret;
}
return rsp.port_count;
}
static int cros_pchg_get_status(struct port_data *port)
{
struct charger_data *charger = port->charger;
struct ec_params_pchg req;
struct ec_response_pchg rsp;
struct device *dev = charger->dev;
int old_status = port->psy_status;
int old_percentage = port->battery_percentage;
int ret;
req.port = port->port_number;
ret = cros_pchg_ec_command(charger, pchg_cmd_version, EC_CMD_PCHG,
&req, sizeof(req), &rsp, sizeof(rsp));
if (ret < 0) {
dev_err(dev, "Unable to get port.%d status (err:%d)\n",
port->port_number, ret);
return ret;
}
switch (rsp.state) {
case PCHG_STATE_RESET:
case PCHG_STATE_INITIALIZED:
case PCHG_STATE_ENABLED:
default:
port->psy_status = POWER_SUPPLY_STATUS_UNKNOWN;
port->charge_type = POWER_SUPPLY_CHARGE_TYPE_NONE;
break;
case PCHG_STATE_DETECTED:
port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
port->charge_type = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
break;
case PCHG_STATE_CHARGING:
port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
port->charge_type = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
break;
case PCHG_STATE_FULL:
port->psy_status = POWER_SUPPLY_STATUS_FULL;
port->charge_type = POWER_SUPPLY_CHARGE_TYPE_NONE;
break;
}
port->battery_percentage = rsp.battery_percentage;
if (port->psy_status != old_status ||
port->battery_percentage != old_percentage)
power_supply_changed(port->psy);
dev_dbg(dev,
"Port %d: state=%d battery=%d%%\n",
port->port_number, rsp.state, rsp.battery_percentage);
return 0;
}
static int cros_pchg_get_port_status(struct port_data *port, bool ratelimit)
{
int ret;
if (ratelimit &&
time_is_after_jiffies(port->last_update + PCHG_CACHE_UPDATE_DELAY))
return 0;
ret = cros_pchg_get_status(port);
if (ret < 0)
return ret;
port->last_update = jiffies;
return ret;
}
static int cros_pchg_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);
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
case POWER_SUPPLY_PROP_CAPACITY:
case POWER_SUPPLY_PROP_CHARGE_TYPE:
cros_pchg_get_port_status(port, true);
break;
default:
break;
}
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
val->intval = port->psy_status;
break;
case POWER_SUPPLY_PROP_CAPACITY:
val->intval = port->battery_percentage;
break;
case POWER_SUPPLY_PROP_CHARGE_TYPE:
val->intval = port->charge_type;
break;
case POWER_SUPPLY_PROP_SCOPE:
val->intval = POWER_SUPPLY_SCOPE_DEVICE;
break;
default:
return -EINVAL;
}
return 0;
}
static int cros_pchg_event(const struct charger_data *charger)
{
int i;
for (i = 0; i < charger->num_registered_psy; i++)
cros_pchg_get_port_status(charger->ports[i], false);
return NOTIFY_OK;
}
static int cros_ec_notify(struct notifier_block *nb,
unsigned long queued_during_suspend,
void *data)
{
struct cros_ec_device *ec_dev = data;
struct charger_data *charger =
container_of(nb, struct charger_data, notifier);
u32 host_event;
if (ec_dev->event_data.event_type != EC_MKBP_EVENT_PCHG ||
ec_dev->event_size != sizeof(host_event))
return NOTIFY_DONE;
host_event = get_unaligned_le32(&ec_dev->event_data.data.host_event);
if (!(host_event & EC_MKBP_PCHG_DEVICE_EVENT))
return NOTIFY_DONE;
return cros_pchg_event(charger);
}
static int cros_pchg_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
struct cros_ec_device *ec_device = ec_dev->ec_dev;
struct power_supply_desc *psy_desc;
struct charger_data *charger;
struct power_supply *psy;
struct port_data *port;
struct notifier_block *nb;
int num_ports;
int ret;
int i;
charger = devm_kzalloc(dev, sizeof(*charger), GFP_KERNEL);
if (!charger)
return -ENOMEM;
charger->dev = dev;
charger->ec_dev = ec_dev;
charger->ec_device = ec_device;
platform_set_drvdata(pdev, charger);
ret = cros_pchg_port_count(charger);
if (ret <= 0) {
/*
* This feature is enabled by the EC and the kernel driver is
* included by default for CrOS devices. Don't need to be loud
* since this error can be normal.
*/
dev_info(dev, "No peripheral charge ports (err:%d)\n", ret);
return -ENODEV;
}
if (!cros_pchg_cmd_ver_check(charger)) {
dev_err(dev, "EC_CMD_PCHG version %d isn't available.\n",
pchg_cmd_version);
return -EOPNOTSUPP;
}
num_ports = ret;
if (num_ports > EC_PCHG_MAX_PORTS) {
dev_err(dev, "Too many peripheral charge ports (%d)\n",
num_ports);
return -ENOBUFS;
}
dev_info(dev, "%d peripheral charge ports found\n", num_ports);
for (i = 0; i < num_ports; i++) {
struct power_supply_config psy_cfg = {};
port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
if (!port)
return -ENOMEM;
port->charger = charger;
port->port_number = i;
snprintf(port->name, sizeof(port->name), PCHG_DIR_NAME, i);
psy_desc = &port->psy_desc;
psy_desc->name = port->name;
psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
psy_desc->get_property = cros_pchg_get_prop;
psy_desc->external_power_changed = NULL;
psy_desc->properties = cros_pchg_props;
psy_desc->num_properties = ARRAY_SIZE(cros_pchg_props);
psy_cfg.drv_data = port;
psy = devm_power_supply_register(dev, psy_desc, &psy_cfg);
if (IS_ERR(psy))
return dev_err_probe(dev, PTR_ERR(psy),
"Failed to register power supply\n");
port->psy = psy;
charger->ports[charger->num_registered_psy++] = port;
}
if (!charger->num_registered_psy)
return -ENODEV;
nb = &charger->notifier;
nb->notifier_call = cros_ec_notify;
ret = blocking_notifier_chain_register(&ec_dev->ec_dev->event_notifier,
nb);
if (ret < 0)
dev_err(dev, "Failed to register notifier (err:%d)\n", ret);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int __maybe_unused cros_pchg_resume(struct device *dev)
{
struct charger_data *charger = dev_get_drvdata(dev);
/*
* Sync all ports on resume in case reports from EC are lost during
* the last suspend.
*/
cros_pchg_event(charger);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(cros_pchg_pm_ops, NULL, cros_pchg_resume);
static const struct platform_device_id cros_pchg_id[] = {
{ DRV_NAME, 0 },
{}
};
MODULE_DEVICE_TABLE(platform, cros_pchg_id);
static struct platform_driver cros_pchg_driver = {
.driver = {
.name = DRV_NAME,
.pm = &cros_pchg_pm_ops,
},
.probe = cros_pchg_probe,
.id_table = cros_pchg_id,
};
module_platform_driver(cros_pchg_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ChromeOS EC peripheral device charger");
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