linux/drivers/power/max8903_charger.c
Chris Lapa c5ed330794 max8903: adds support for initiation via device tree
Adds support for device tree to setup a max8903 battery charger. DC and USB
validity are determined by looking the presence of the dok and uok gpios.

Signed-off-by: Chris Lapa <chris@lapa.com.au>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2016-06-28 20:16:26 +02:00

460 lines
11 KiB
C

/*
* max8903_charger.c - Maxim 8903 USB/Adapter Charger Driver
*
* Copyright (C) 2011 Samsung Electronics
* MyungJoo Ham <myungjoo.ham@samsung.com>
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/slab.h>
#include <linux/power_supply.h>
#include <linux/platform_device.h>
#include <linux/power/max8903_charger.h>
struct max8903_data {
struct max8903_pdata *pdata;
struct device *dev;
struct power_supply *psy;
struct power_supply_desc psy_desc;
bool fault;
bool usb_in;
bool ta_in;
};
static enum power_supply_property max8903_charger_props[] = {
POWER_SUPPLY_PROP_STATUS, /* Charger status output */
POWER_SUPPLY_PROP_ONLINE, /* External power source */
POWER_SUPPLY_PROP_HEALTH, /* Fault or OK */
};
static int max8903_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct max8903_data *data = power_supply_get_drvdata(psy);
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
if (gpio_is_valid(data->pdata->chg)) {
if (gpio_get_value(data->pdata->chg) == 0)
val->intval = POWER_SUPPLY_STATUS_CHARGING;
else if (data->usb_in || data->ta_in)
val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
else
val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
}
break;
case POWER_SUPPLY_PROP_ONLINE:
val->intval = 0;
if (data->usb_in || data->ta_in)
val->intval = 1;
break;
case POWER_SUPPLY_PROP_HEALTH:
val->intval = POWER_SUPPLY_HEALTH_GOOD;
if (data->fault)
val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
break;
default:
return -EINVAL;
}
return 0;
}
static irqreturn_t max8903_dcin(int irq, void *_data)
{
struct max8903_data *data = _data;
struct max8903_pdata *pdata = data->pdata;
bool ta_in;
enum power_supply_type old_type;
ta_in = gpio_get_value(pdata->dok) ? false : true;
if (ta_in == data->ta_in)
return IRQ_HANDLED;
data->ta_in = ta_in;
/* Set Current-Limit-Mode 1:DC 0:USB */
if (gpio_is_valid(pdata->dcm))
gpio_set_value(pdata->dcm, ta_in ? 1 : 0);
/* Charger Enable / Disable (cen is negated) */
if (gpio_is_valid(pdata->cen))
gpio_set_value(pdata->cen, ta_in ? 0 :
(data->usb_in ? 0 : 1));
dev_dbg(data->dev, "TA(DC-IN) Charger %s.\n", ta_in ?
"Connected" : "Disconnected");
old_type = data->psy_desc.type;
if (data->ta_in)
data->psy_desc.type = POWER_SUPPLY_TYPE_MAINS;
else if (data->usb_in)
data->psy_desc.type = POWER_SUPPLY_TYPE_USB;
else
data->psy_desc.type = POWER_SUPPLY_TYPE_BATTERY;
if (old_type != data->psy_desc.type)
power_supply_changed(data->psy);
return IRQ_HANDLED;
}
static irqreturn_t max8903_usbin(int irq, void *_data)
{
struct max8903_data *data = _data;
struct max8903_pdata *pdata = data->pdata;
bool usb_in;
enum power_supply_type old_type;
usb_in = gpio_get_value(pdata->uok) ? false : true;
if (usb_in == data->usb_in)
return IRQ_HANDLED;
data->usb_in = usb_in;
/* Do not touch Current-Limit-Mode */
/* Charger Enable / Disable (cen is negated) */
if (gpio_is_valid(pdata->cen))
gpio_set_value(pdata->cen, usb_in ? 0 :
(data->ta_in ? 0 : 1));
dev_dbg(data->dev, "USB Charger %s.\n", usb_in ?
"Connected" : "Disconnected");
old_type = data->psy_desc.type;
if (data->ta_in)
data->psy_desc.type = POWER_SUPPLY_TYPE_MAINS;
else if (data->usb_in)
data->psy_desc.type = POWER_SUPPLY_TYPE_USB;
else
data->psy_desc.type = POWER_SUPPLY_TYPE_BATTERY;
if (old_type != data->psy_desc.type)
power_supply_changed(data->psy);
return IRQ_HANDLED;
}
static irqreturn_t max8903_fault(int irq, void *_data)
{
struct max8903_data *data = _data;
struct max8903_pdata *pdata = data->pdata;
bool fault;
fault = gpio_get_value(pdata->flt) ? false : true;
if (fault == data->fault)
return IRQ_HANDLED;
data->fault = fault;
if (fault)
dev_err(data->dev, "Charger suffers a fault and stops.\n");
else
dev_err(data->dev, "Charger recovered from a fault.\n");
return IRQ_HANDLED;
}
static struct max8903_pdata *max8903_parse_dt_data(struct device *dev)
{
struct device_node *np = dev->of_node;
struct max8903_pdata *pdata = NULL;
if (!np)
return NULL;
pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return NULL;
pdata->dc_valid = false;
pdata->usb_valid = false;
pdata->cen = of_get_named_gpio(np, "cen-gpios", 0);
if (!gpio_is_valid(pdata->cen))
pdata->cen = -EINVAL;
pdata->chg = of_get_named_gpio(np, "chg-gpios", 0);
if (!gpio_is_valid(pdata->chg))
pdata->chg = -EINVAL;
pdata->flt = of_get_named_gpio(np, "flt-gpios", 0);
if (!gpio_is_valid(pdata->flt))
pdata->flt = -EINVAL;
pdata->usus = of_get_named_gpio(np, "usus-gpios", 0);
if (!gpio_is_valid(pdata->usus))
pdata->usus = -EINVAL;
pdata->dcm = of_get_named_gpio(np, "dcm-gpios", 0);
if (!gpio_is_valid(pdata->dcm))
pdata->dcm = -EINVAL;
pdata->dok = of_get_named_gpio(np, "dok-gpios", 0);
if (!gpio_is_valid(pdata->dok))
pdata->dok = -EINVAL;
else
pdata->dc_valid = true;
pdata->uok = of_get_named_gpio(np, "uok-gpios", 0);
if (!gpio_is_valid(pdata->uok))
pdata->uok = -EINVAL;
else
pdata->usb_valid = true;
return pdata;
}
static int max8903_setup_gpios(struct platform_device *pdev)
{
struct max8903_data *data = platform_get_drvdata(pdev);
struct device *dev = &pdev->dev;
struct max8903_pdata *pdata = pdev->dev.platform_data;
int ret = 0;
int gpio;
int ta_in = 0;
int usb_in = 0;
if (pdata->dc_valid) {
if (gpio_is_valid(pdata->dok)) {
ret = devm_gpio_request(dev, pdata->dok,
data->psy_desc.name);
if (ret) {
dev_err(dev,
"Failed GPIO request for dok: %d err %d\n",
pdata->dok, ret);
return ret;
}
gpio = pdata->dok; /* PULL_UPed Interrupt */
ta_in = gpio_get_value(gpio) ? 0 : 1;
} else {
dev_err(dev, "When DC is wired, DOK should be wired as well.\n");
return -EINVAL;
}
}
if (gpio_is_valid(pdata->dcm)) {
ret = devm_gpio_request(dev, pdata->dcm, data->psy_desc.name);
if (ret) {
dev_err(dev,
"Failed GPIO request for dcm: %d err %d\n",
pdata->dcm, ret);
return ret;
}
gpio = pdata->dcm; /* Output */
gpio_set_value(gpio, ta_in);
}
if (pdata->usb_valid) {
if (gpio_is_valid(pdata->uok)) {
ret = devm_gpio_request(dev, pdata->uok,
data->psy_desc.name);
if (ret) {
dev_err(dev,
"Failed GPIO request for uok: %d err %d\n",
pdata->uok, ret);
return ret;
}
gpio = pdata->uok;
usb_in = gpio_get_value(gpio) ? 0 : 1;
} else {
dev_err(dev, "When USB is wired, UOK should be wired."
"as well.\n");
return -EINVAL;
}
}
if (gpio_is_valid(pdata->cen)) {
ret = devm_gpio_request(dev, pdata->cen, data->psy_desc.name);
if (ret) {
dev_err(dev,
"Failed GPIO request for cen: %d err %d\n",
pdata->cen, ret);
return ret;
}
gpio_set_value(pdata->cen, (ta_in || usb_in) ? 0 : 1);
}
if (gpio_is_valid(pdata->chg)) {
ret = devm_gpio_request(dev, pdata->chg, data->psy_desc.name);
if (ret) {
dev_err(dev,
"Failed GPIO request for chg: %d err %d\n",
pdata->chg, ret);
return ret;
}
}
if (gpio_is_valid(pdata->flt)) {
ret = devm_gpio_request(dev, pdata->flt, data->psy_desc.name);
if (ret) {
dev_err(dev,
"Failed GPIO request for flt: %d err %d\n",
pdata->flt, ret);
return ret;
}
}
if (gpio_is_valid(pdata->usus)) {
ret = devm_gpio_request(dev, pdata->usus, data->psy_desc.name);
if (ret) {
dev_err(dev,
"Failed GPIO request for usus: %d err %d\n",
pdata->usus, ret);
return ret;
}
}
data->fault = false;
data->ta_in = ta_in;
data->usb_in = usb_in;
return 0;
}
static int max8903_probe(struct platform_device *pdev)
{
struct max8903_data *data;
struct device *dev = &pdev->dev;
struct max8903_pdata *pdata = pdev->dev.platform_data;
struct power_supply_config psy_cfg = {};
int ret = 0;
data = devm_kzalloc(dev, sizeof(struct max8903_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
if (IS_ENABLED(CONFIG_OF) && !pdata && dev->of_node)
pdata = max8903_parse_dt_data(dev);
if (!pdata) {
dev_err(dev, "No platform data.\n");
return -EINVAL;
}
pdev->dev.platform_data = pdata;
data->pdata = pdata;
data->dev = dev;
platform_set_drvdata(pdev, data);
if (pdata->dc_valid == false && pdata->usb_valid == false) {
dev_err(dev, "No valid power sources.\n");
return -EINVAL;
}
ret = max8903_setup_gpios(pdev);
if (ret)
return ret;
data->psy_desc.name = "max8903_charger";
data->psy_desc.type = (data->ta_in) ? POWER_SUPPLY_TYPE_MAINS :
((data->usb_in) ? POWER_SUPPLY_TYPE_USB :
POWER_SUPPLY_TYPE_BATTERY);
data->psy_desc.get_property = max8903_get_property;
data->psy_desc.properties = max8903_charger_props;
data->psy_desc.num_properties = ARRAY_SIZE(max8903_charger_props);
psy_cfg.of_node = dev->of_node;
psy_cfg.drv_data = data;
data->psy = devm_power_supply_register(dev, &data->psy_desc, &psy_cfg);
if (IS_ERR(data->psy)) {
dev_err(dev, "failed: power supply register.\n");
return PTR_ERR(data->psy);
}
if (pdata->dc_valid) {
ret = devm_request_threaded_irq(dev, gpio_to_irq(pdata->dok),
NULL, max8903_dcin,
IRQF_TRIGGER_FALLING |
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
"MAX8903 DC IN", data);
if (ret) {
dev_err(dev, "Cannot request irq %d for DC (%d)\n",
gpio_to_irq(pdata->dok), ret);
return ret;
}
}
if (pdata->usb_valid) {
ret = devm_request_threaded_irq(dev, gpio_to_irq(pdata->uok),
NULL, max8903_usbin,
IRQF_TRIGGER_FALLING |
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
"MAX8903 USB IN", data);
if (ret) {
dev_err(dev, "Cannot request irq %d for USB (%d)\n",
gpio_to_irq(pdata->uok), ret);
return ret;
}
}
if (gpio_is_valid(pdata->flt)) {
ret = devm_request_threaded_irq(dev, gpio_to_irq(pdata->flt),
NULL, max8903_fault,
IRQF_TRIGGER_FALLING |
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
"MAX8903 Fault", data);
if (ret) {
dev_err(dev, "Cannot request irq %d for Fault (%d)\n",
gpio_to_irq(pdata->flt), ret);
return ret;
}
}
return 0;
}
static const struct of_device_id max8903_match_ids[] = {
{ .compatible = "maxim,max8903", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, max8903_match_ids);
static struct platform_driver max8903_driver = {
.probe = max8903_probe,
.driver = {
.name = "max8903-charger",
.of_match_table = max8903_match_ids
},
};
module_platform_driver(max8903_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MAX8903 Charger Driver");
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
MODULE_ALIAS("platform:max8903-charger");