/*
* Battery driver for a Greybus module.
*
* Copyright 2014 Google Inc.
* Copyright 2014 Linaro Ltd.
*
* Released under the GPLv2 only.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/power_supply.h>
#include "greybus.h"
struct gb_battery {
/*
* The power supply api changed in 4.1, so handle both the old
* and new apis in the same driver for now, until this is merged
* upstream, when all of these version checks can be removed.
*/
#ifdef DRIVER_OWNS_PSY_STRUCT
struct power_supply bat;
#define to_gb_battery(x) container_of(x, struct gb_battery, bat)
#else
struct power_supply *bat;
struct power_supply_desc desc;
#define to_gb_battery(x) power_supply_get_drvdata(x)
#endif
// FIXME
// we will want to keep the battery stats in here as we will be getting
// updates from the SVC "on the fly" so we don't have to always go ask
// the battery for some information. Hopefully...
struct gb_connection *connection;
};
static int get_tech(struct gb_battery *gb)
{
struct gb_battery_technology_response tech_response;
u32 technology;
int retval;
retval = gb_operation_sync(gb->connection, GB_BATTERY_TYPE_TECHNOLOGY,
NULL, 0,
&tech_response, sizeof(tech_response));
if (retval)
return retval;
/*
* Map greybus values to power_supply values. Hopefully these are
* "identical" which should allow gcc to optimize the code away to
* nothing.
*/
technology = le32_to_cpu(tech_response.technology);
switch (technology) {
case GB_BATTERY_TECH_NiMH:
technology = POWER_SUPPLY_TECHNOLOGY_NiMH;
break;
case GB_BATTERY_TECH_LION:
technology = POWER_SUPPLY_TECHNOLOGY_LION;
break;
case GB_BATTERY_TECH_LIPO:
technology = POWER_SUPPLY_TECHNOLOGY_LIPO;
break;
case GB_BATTERY_TECH_LiFe:
technology = POWER_SUPPLY_TECHNOLOGY_LiFe;
break;
case GB_BATTERY_TECH_NiCd:
technology = POWER_SUPPLY_TECHNOLOGY_NiCd;
break;
case GB_BATTERY_TECH_LiMn:
technology = POWER_SUPPLY_TECHNOLOGY_LiMn;
break;
case GB_BATTERY_TECH_UNKNOWN:
default:
technology = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
break;
}
return technology;
}
static int get_status(struct gb_battery *gb)
{
struct gb_battery_status_response status_response;
u16 battery_status;
int retval;
retval = gb_operation_sync(gb->connection, GB_BATTERY_TYPE_STATUS,
NULL, 0,
&status_response, sizeof(status_response));
if (retval)
return retval;
/*
* Map greybus values to power_supply values. Hopefully these are
* "identical" which should allow gcc to optimize the code away to
* nothing.
*/
battery_status = le16_to_cpu(status_response.battery_status);
switch (battery_status) {
case GB_BATTERY_STATUS_CHARGING:
battery_status = POWER_SUPPLY_STATUS_CHARGING;
break;
case GB_BATTERY_STATUS_DISCHARGING:
battery_status = POWER_SUPPLY_STATUS_DISCHARGING;
break;
case GB_BATTERY_STATUS_NOT_CHARGING:
battery_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
break;
case GB_BATTERY_STATUS_FULL:
battery_status = POWER_SUPPLY_STATUS_FULL;
break;
case GB_BATTERY_STATUS_UNKNOWN:
default:
battery_status = POWER_SUPPLY_STATUS_UNKNOWN;
break;
}
return battery_status;
}
static int get_max_voltage(struct gb_battery *gb)
{
struct gb_battery_max_voltage_response volt_response;
u32 max_voltage;
int retval;
retval = gb_operation_sync(gb->connection, GB_BATTERY_TYPE_MAX_VOLTAGE,
NULL, 0,
&volt_response, sizeof(volt_response));
if (retval)
return retval;
max_voltage = le32_to_cpu(volt_response.max_voltage);
return max_voltage;
}
static int get_percent_capacity(struct gb_battery *gb)
{
struct gb_battery_capacity_response capacity_response;
u32 capacity;
int retval;
retval = gb_operation_sync(gb->connection,
GB_BATTERY_TYPE_PERCENT_CAPACITY,
NULL, 0, &capacity_response,
sizeof(capacity_response));
if (retval)
return retval;
capacity = le32_to_cpu(capacity_response.capacity);
return capacity;
}
static int get_temp(struct gb_battery *gb)
{
struct gb_battery_temperature_response temp_response;
u32 temperature;
int retval;
retval = gb_operation_sync(gb->connection, GB_BATTERY_TYPE_TEMPERATURE,
NULL, 0,
&temp_response, sizeof(temp_response));
if (retval)
return retval;
temperature = le32_to_cpu(temp_response.temperature);
return temperature;
}
static int get_voltage(struct gb_battery *gb)
{
struct gb_battery_voltage_response voltage_response;
u32 voltage;
int retval;
retval = gb_operation_sync(gb->connection, GB_BATTERY_TYPE_VOLTAGE,
NULL, 0,
&voltage_response, sizeof(voltage_response));
if (retval)
return retval;
voltage = le32_to_cpu(voltage_response.voltage);
return voltage;
}
static int get_property(struct power_supply *b,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct gb_battery *gb = to_gb_battery(b);
switch (psp) {
case POWER_SUPPLY_PROP_TECHNOLOGY:
val->intval = get_tech(gb);
break;
case POWER_SUPPLY_PROP_STATUS:
val->intval = get_status(gb);
break;
case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
val->intval = get_max_voltage(gb);
break;
case POWER_SUPPLY_PROP_CAPACITY:
val->intval = get_percent_capacity(gb);
break;
case POWER_SUPPLY_PROP_TEMP:
val->intval = get_temp(gb);
break;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
val->intval = get_voltage(gb);
break;
default:
return -EINVAL;
}
return (val->intval < 0) ? val->intval : 0;
}
// FIXME - verify this list, odds are some can be removed and others added.
static enum power_supply_property battery_props[] = {
POWER_SUPPLY_PROP_TECHNOLOGY,
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
POWER_SUPPLY_PROP_CAPACITY,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
};
#ifdef DRIVER_OWNS_PSY_STRUCT
static int init_and_register(struct gb_connection *connection,
struct gb_battery *gb)
{
// FIXME - get a better (i.e. unique) name
// FIXME - anything else needs to be set?
gb->bat.name = "gb_battery";
gb->bat.type = POWER_SUPPLY_TYPE_BATTERY;
gb->bat.properties = battery_props;
gb->bat.num_properties = ARRAY_SIZE(battery_props);
gb->bat.get_property = get_property;
return power_supply_register(&connection->bundle->dev, &gb->bat);
}
#else
static int init_and_register(struct gb_connection *connection,
struct gb_battery *gb)
{
struct power_supply_config cfg = {};
cfg.drv_data = gb;
// FIXME - get a better (i.e. unique) name
// FIXME - anything else needs to be set?
gb->desc.name = "gb_battery";
gb->desc.type = POWER_SUPPLY_TYPE_BATTERY;
gb->desc.properties = battery_props;
gb->desc.num_properties = ARRAY_SIZE(battery_props);
gb->desc.get_property = get_property;
gb->bat = power_supply_register(&connection->bundle->dev,
&gb->desc, &cfg);
if (IS_ERR(gb->bat))
return PTR_ERR(gb->bat);
return 0;
}
#endif
static int gb_battery_connection_init(struct gb_connection *connection)
{
struct gb_battery *gb;
int retval;
gb = kzalloc(sizeof(*gb), GFP_KERNEL);
if (!gb)
return -ENOMEM;
gb->connection = connection;
connection->private = gb;
retval = init_and_register(connection, gb);
if (retval)
kfree(gb);
return retval;
}
static void gb_battery_connection_exit(struct gb_connection *connection)
{
struct gb_battery *gb = connection->private;
#ifdef DRIVER_OWNS_PSY_STRUCT
power_supply_unregister(&gb->bat);
#else
power_supply_unregister(gb->bat);
#endif
kfree(gb);
}
static struct gb_protocol battery_protocol = {
.name = "battery",
.id = GREYBUS_PROTOCOL_BATTERY,
.major = GB_BATTERY_VERSION_MAJOR,
.minor = GB_BATTERY_VERSION_MINOR,
.connection_init = gb_battery_connection_init,
.connection_exit = gb_battery_connection_exit,
.request_recv = NULL, /* no incoming requests */
};
gb_protocol_driver(&battery_protocol);
MODULE_LICENSE("GPL v2");
