/*
* Battery charger driver for TI's tps65217
*
* Copyright (c) 2015, Collabora Ltd.
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
* This program is distributed in the hope 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.
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* Battery charger driver for TI's tps65217
*/
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/power_supply.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tps65217.h>
#define POLL_INTERVAL (HZ * 2)
struct tps65217_charger {
struct tps65217 *tps;
struct device *dev;
struct power_supply *ac;
int ac_online;
int prev_ac_online;
struct task_struct *poll_task;
};
static enum power_supply_property tps65217_ac_props[] = {
POWER_SUPPLY_PROP_ONLINE,
};
static int tps65217_config_charger(struct tps65217_charger *charger)
{
int ret;
dev_dbg(charger->dev, "%s\n", __func__);
/*
* tps65217 rev. G, p. 31 (see p. 32 for NTC schematic)
*
* The device can be configured to support a 100k NTC (B = 3960) by
* setting the the NTC_TYPE bit in register CHGCONFIG1 to 1. However it
* is not recommended to do so. In sleep mode, the charger continues
* charging the battery, but all register values are reset to default
* values. Therefore, the charger would get the wrong temperature
* information. If 100k NTC setting is required, please contact the
* factory.
*
* ATTENTION, conflicting information, from p. 46
*
* NTC TYPE (for battery temperature measurement)
* 0 – 100k (curve 1, B = 3960)
* 1 – 10k (curve 2, B = 3480) (default on reset)
*
*/
ret = tps65217_clear_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
TPS65217_CHGCONFIG1_NTC_TYPE,
TPS65217_PROTECT_NONE);
if (ret) {
dev_err(charger->dev,
"failed to set 100k NTC setting: %d\n", ret);
return ret;
}
return 0;
}
static int tps65217_enable_charging(struct tps65217_charger *charger)
{
int ret;
/* charger already enabled */
if (charger->ac_online)
return 0;
dev_dbg(charger->dev, "%s: enable charging\n", __func__);
ret = tps65217_set_bits(charger->tps, TPS65217_REG_CHGCONFIG1,
TPS65217_CHGCONFIG1_CHG_EN,
TPS65217_CHGCONFIG1_CHG_EN,
TPS65217_PROTECT_NONE);
if (ret) {
dev_err(charger->dev,
"%s: Error in writing CHG_EN in reg 0x%x: %d\n",
__func__, TPS65217_REG_CHGCONFIG1, ret);
return ret;
}
charger->ac_online = 1;
return 0;
}
static int tps65217_ac_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct tps65217_charger *charger = power_supply_get_drvdata(psy);
if (psp == POWER_SUPPLY_PROP_ONLINE) {
val->intval = charger->ac_online;
return 0;
}
return -EINVAL;
}
static irqreturn_t tps65217_charger_irq(int irq, void *dev)
{
int ret, val;
struct tps65217_charger *charger = dev;
charger->prev_ac_online = charger->ac_online;
ret = tps65217_reg_read(charger->tps, TPS65217_REG_STATUS, &val);
if (ret < 0) {
dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
__func__, TPS65217_REG_STATUS);
return IRQ_HANDLED;
}
dev_dbg(charger->dev, "%s: 0x%x\n", __func__, val);
/* check for AC status bit */
if (val & TPS65217_STATUS_ACPWR) {
ret = tps65217_enable_charging(charger);
if (ret) {
dev_err(charger->dev,
"failed to enable charger: %d\n", ret);
return IRQ_HANDLED;
}
} else {
charger->ac_online = 0;
}
if (charger->prev_ac_online != charger->ac_online)
power_supply_changed(charger->ac);
ret = tps65217_reg_read(charger->tps, TPS65217_REG_CHGCONFIG0, &val);
if (ret < 0) {
dev_err(charger->dev, "%s: Error in reading reg 0x%x\n",
__func__, TPS65217_REG_CHGCONFIG0);
return IRQ_HANDLED;
}
if (val & TPS65217_CHGCONFIG0_ACTIVE)
dev_dbg(charger->dev, "%s: charger is charging\n", __func__);
else
dev_dbg(charger->dev,
"%s: charger is NOT charging\n", __func__);
return IRQ_HANDLED;
}
static int tps65217_charger_poll_task(void *data)
{
set_freezable();
while (!kthread_should_stop()) {
schedule_timeout_interruptible(POLL_INTERVAL);
try_to_freeze();
tps65217_charger_irq(-1, data);
}
return 0;
}
static const struct power_supply_desc tps65217_charger_desc = {
.name = "tps65217-ac",
.type = POWER_SUPPLY_TYPE_MAINS,
.get_property = tps65217_ac_get_property,
.properties = tps65217_ac_props,
.num_properties = ARRAY_SIZE(tps65217_ac_props),
};
static int tps65217_charger_probe(struct platform_device *pdev)
{
struct tps65217 *tps = dev_get_drvdata(pdev->dev.parent);
struct tps65217_charger *charger;
struct power_supply_config cfg = {};
int ret;
dev_dbg(&pdev->dev, "%s\n", __func__);
charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
if (!charger)
return -ENOMEM;
charger->tps = tps;
charger->dev = &pdev->dev;
cfg.of_node = pdev->dev.of_node;
cfg.drv_data = charger;
charger->ac = devm_power_supply_register(&pdev->dev,
&tps65217_charger_desc,
&cfg);
if (IS_ERR(charger->ac)) {
dev_err(&pdev->dev, "failed: power supply register\n");
return PTR_ERR(charger->ac);
}
ret = tps65217_config_charger(charger);
if (ret < 0) {
dev_err(charger->dev, "charger config failed, err %d\n", ret);
return ret;
}
charger->poll_task = kthread_run(tps65217_charger_poll_task,
charger, "ktps65217charger");
if (IS_ERR(charger->poll_task)) {
ret = PTR_ERR(charger->poll_task);
dev_err(charger->dev, "Unable to run kthread err %d\n", ret);
return ret;
}
return 0;
}
static int tps65217_charger_remove(struct platform_device *pdev)
{
struct tps65217_charger *charger = platform_get_drvdata(pdev);
kthread_stop(charger->poll_task);
return 0;
}
static const struct of_device_id tps65217_charger_match_table[] = {
{ .compatible = "ti,tps65217-charger", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, tps65217_charger_match_table);
static struct platform_driver tps65217_charger_driver = {
.probe = tps65217_charger_probe,
.remove = tps65217_charger_remove,
.driver = {
.name = "tps65217-charger",
.of_match_table = of_match_ptr(tps65217_charger_match_table),
},
};
module_platform_driver(tps65217_charger_driver);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Enric Balletbo Serra <enric.balletbo@collabora.com>");
MODULE_DESCRIPTION("TPS65217 battery charger driver");
