linux_dsm_epyc7002/drivers/power/supply/pcf50633-charger.c
Sebastian Reichel 451ba0e436 power: supply: pcf50633: fix race-condition in sysfs registration
This registers custom sysfs properties using the native functionality
of the power-supply framework, which cleans up the code a bit and
fixes a race-condition. Before this patch the sysfs attributes were
not properly registered to udev.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2018-12-13 00:16:24 +01:00

479 lines
12 KiB
C

/* NXP PCF50633 Main Battery Charger Driver
*
* (C) 2006-2008 by Openmoko, Inc.
* Author: Balaji Rao <balajirrao@openmoko.org>
* All rights reserved.
*
* Broken down from monstrous PCF50633 driver mainly by
* Harald Welte, Andy Green and Werner Almesberger
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/mfd/pcf50633/core.h>
#include <linux/mfd/pcf50633/mbc.h>
struct pcf50633_mbc {
struct pcf50633 *pcf;
int adapter_online;
int usb_online;
struct power_supply *usb;
struct power_supply *adapter;
struct power_supply *ac;
};
int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
{
struct pcf50633_mbc *mbc = platform_get_drvdata(pcf->mbc_pdev);
int ret = 0;
u8 bits;
u8 mbcs2, chgmod;
unsigned int mbcc5;
if (ma >= 1000) {
bits = PCF50633_MBCC7_USB_1000mA;
ma = 1000;
} else if (ma >= 500) {
bits = PCF50633_MBCC7_USB_500mA;
ma = 500;
} else if (ma >= 100) {
bits = PCF50633_MBCC7_USB_100mA;
ma = 100;
} else {
bits = PCF50633_MBCC7_USB_SUSPEND;
ma = 0;
}
ret = pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC7,
PCF50633_MBCC7_USB_MASK, bits);
if (ret)
dev_err(pcf->dev, "error setting usb curlim to %d mA\n", ma);
else
dev_info(pcf->dev, "usb curlim to %d mA\n", ma);
/*
* We limit the charging current to be the USB current limit.
* The reason is that on pcf50633, when it enters PMU Standby mode,
* which it does when the device goes "off", the USB current limit
* reverts to the variant default. In at least one common case, that
* default is 500mA. By setting the charging current to be the same
* as the USB limit we set here before PMU standby, we enforce it only
* using the correct amount of current even when the USB current limit
* gets reset to the wrong thing
*/
if (mbc->pcf->pdata->charger_reference_current_ma) {
mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
if (mbcc5 > 255)
mbcc5 = 255;
pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);
}
mbcs2 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2);
chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);
/* If chgmod == BATFULL, setting chgena has no effect.
* Datasheet says we need to set resume instead but when autoresume is
* used resume doesn't work. Clear and set chgena instead.
*/
if (chgmod != PCF50633_MBCS2_MBC_BAT_FULL)
pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,
PCF50633_MBCC1_CHGENA, PCF50633_MBCC1_CHGENA);
else {
pcf50633_reg_clear_bits(pcf, PCF50633_REG_MBCC1,
PCF50633_MBCC1_CHGENA);
pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,
PCF50633_MBCC1_CHGENA, PCF50633_MBCC1_CHGENA);
}
power_supply_changed(mbc->usb);
return ret;
}
EXPORT_SYMBOL_GPL(pcf50633_mbc_usb_curlim_set);
int pcf50633_mbc_get_status(struct pcf50633 *pcf)
{
struct pcf50633_mbc *mbc = platform_get_drvdata(pcf->mbc_pdev);
int status = 0;
u8 chgmod;
if (!mbc)
return 0;
chgmod = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2)
& PCF50633_MBCS2_MBC_MASK;
if (mbc->usb_online)
status |= PCF50633_MBC_USB_ONLINE;
if (chgmod == PCF50633_MBCS2_MBC_USB_PRE ||
chgmod == PCF50633_MBCS2_MBC_USB_PRE_WAIT ||
chgmod == PCF50633_MBCS2_MBC_USB_FAST ||
chgmod == PCF50633_MBCS2_MBC_USB_FAST_WAIT)
status |= PCF50633_MBC_USB_ACTIVE;
if (mbc->adapter_online)
status |= PCF50633_MBC_ADAPTER_ONLINE;
if (chgmod == PCF50633_MBCS2_MBC_ADP_PRE ||
chgmod == PCF50633_MBCS2_MBC_ADP_PRE_WAIT ||
chgmod == PCF50633_MBCS2_MBC_ADP_FAST ||
chgmod == PCF50633_MBCS2_MBC_ADP_FAST_WAIT)
status |= PCF50633_MBC_ADAPTER_ACTIVE;
return status;
}
EXPORT_SYMBOL_GPL(pcf50633_mbc_get_status);
int pcf50633_mbc_get_usb_online_status(struct pcf50633 *pcf)
{
struct pcf50633_mbc *mbc = platform_get_drvdata(pcf->mbc_pdev);
if (!mbc)
return 0;
return mbc->usb_online;
}
EXPORT_SYMBOL_GPL(pcf50633_mbc_get_usb_online_status);
static ssize_t
show_chgmode(struct device *dev, struct device_attribute *attr, char *buf)
{
struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
u8 mbcs2 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2);
u8 chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);
return sprintf(buf, "%d\n", chgmod);
}
static DEVICE_ATTR(chgmode, S_IRUGO, show_chgmode, NULL);
static ssize_t
show_usblim(struct device *dev, struct device_attribute *attr, char *buf)
{
struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
PCF50633_MBCC7_USB_MASK;
unsigned int ma;
if (usblim == PCF50633_MBCC7_USB_1000mA)
ma = 1000;
else if (usblim == PCF50633_MBCC7_USB_500mA)
ma = 500;
else if (usblim == PCF50633_MBCC7_USB_100mA)
ma = 100;
else
ma = 0;
return sprintf(buf, "%u\n", ma);
}
static ssize_t set_usblim(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
unsigned long ma;
int ret;
ret = kstrtoul(buf, 10, &ma);
if (ret)
return ret;
pcf50633_mbc_usb_curlim_set(mbc->pcf, ma);
return count;
}
static DEVICE_ATTR(usb_curlim, S_IRUGO | S_IWUSR, show_usblim, set_usblim);
static ssize_t
show_chglim(struct device *dev, struct device_attribute *attr, char *buf)
{
struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
u8 mbcc5 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC5);
unsigned int ma;
if (!mbc->pcf->pdata->charger_reference_current_ma)
return -ENODEV;
ma = (mbc->pcf->pdata->charger_reference_current_ma * mbcc5) >> 8;
return sprintf(buf, "%u\n", ma);
}
static ssize_t set_chglim(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
unsigned long ma;
unsigned int mbcc5;
int ret;
if (!mbc->pcf->pdata->charger_reference_current_ma)
return -ENODEV;
ret = kstrtoul(buf, 10, &ma);
if (ret)
return ret;
mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
if (mbcc5 > 255)
mbcc5 = 255;
pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);
return count;
}
/*
* This attribute allows to change MBC charging limit on the fly
* independently of usb current limit. It also gets set automatically every
* time usb current limit is changed.
*/
static DEVICE_ATTR(chg_curlim, S_IRUGO | S_IWUSR, show_chglim, set_chglim);
static struct attribute *pcf50633_mbc_sysfs_attrs[] = {
&dev_attr_chgmode.attr,
&dev_attr_usb_curlim.attr,
&dev_attr_chg_curlim.attr,
NULL,
};
ATTRIBUTE_GROUPS(pcf50633_mbc_sysfs);
static void
pcf50633_mbc_irq_handler(int irq, void *data)
{
struct pcf50633_mbc *mbc = data;
/* USB */
if (irq == PCF50633_IRQ_USBINS) {
mbc->usb_online = 1;
} else if (irq == PCF50633_IRQ_USBREM) {
mbc->usb_online = 0;
pcf50633_mbc_usb_curlim_set(mbc->pcf, 0);
}
/* Adapter */
if (irq == PCF50633_IRQ_ADPINS)
mbc->adapter_online = 1;
else if (irq == PCF50633_IRQ_ADPREM)
mbc->adapter_online = 0;
power_supply_changed(mbc->ac);
power_supply_changed(mbc->usb);
power_supply_changed(mbc->adapter);
if (mbc->pcf->pdata->mbc_event_callback)
mbc->pcf->pdata->mbc_event_callback(mbc->pcf, irq);
}
static int adapter_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct pcf50633_mbc *mbc = power_supply_get_drvdata(psy);
int ret = 0;
switch (psp) {
case POWER_SUPPLY_PROP_ONLINE:
val->intval = mbc->adapter_online;
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static int usb_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct pcf50633_mbc *mbc = power_supply_get_drvdata(psy);
int ret = 0;
u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
PCF50633_MBCC7_USB_MASK;
switch (psp) {
case POWER_SUPPLY_PROP_ONLINE:
val->intval = mbc->usb_online &&
(usblim <= PCF50633_MBCC7_USB_500mA);
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static int ac_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct pcf50633_mbc *mbc = power_supply_get_drvdata(psy);
int ret = 0;
u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
PCF50633_MBCC7_USB_MASK;
switch (psp) {
case POWER_SUPPLY_PROP_ONLINE:
val->intval = mbc->usb_online &&
(usblim == PCF50633_MBCC7_USB_1000mA);
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static enum power_supply_property power_props[] = {
POWER_SUPPLY_PROP_ONLINE,
};
static const u8 mbc_irq_handlers[] = {
PCF50633_IRQ_ADPINS,
PCF50633_IRQ_ADPREM,
PCF50633_IRQ_USBINS,
PCF50633_IRQ_USBREM,
PCF50633_IRQ_BATFULL,
PCF50633_IRQ_CHGHALT,
PCF50633_IRQ_THLIMON,
PCF50633_IRQ_THLIMOFF,
PCF50633_IRQ_USBLIMON,
PCF50633_IRQ_USBLIMOFF,
PCF50633_IRQ_LOWSYS,
PCF50633_IRQ_LOWBAT,
};
static const struct power_supply_desc pcf50633_mbc_adapter_desc = {
.name = "adapter",
.type = POWER_SUPPLY_TYPE_MAINS,
.properties = power_props,
.num_properties = ARRAY_SIZE(power_props),
.get_property = &adapter_get_property,
};
static const struct power_supply_desc pcf50633_mbc_usb_desc = {
.name = "usb",
.type = POWER_SUPPLY_TYPE_USB,
.properties = power_props,
.num_properties = ARRAY_SIZE(power_props),
.get_property = usb_get_property,
};
static const struct power_supply_desc pcf50633_mbc_ac_desc = {
.name = "ac",
.type = POWER_SUPPLY_TYPE_MAINS,
.properties = power_props,
.num_properties = ARRAY_SIZE(power_props),
.get_property = ac_get_property,
};
static int pcf50633_mbc_probe(struct platform_device *pdev)
{
struct power_supply_config psy_cfg = {};
struct power_supply_config usb_psy_cfg;
struct pcf50633_mbc *mbc;
int i;
u8 mbcs1;
mbc = devm_kzalloc(&pdev->dev, sizeof(*mbc), GFP_KERNEL);
if (!mbc)
return -ENOMEM;
platform_set_drvdata(pdev, mbc);
mbc->pcf = dev_to_pcf50633(pdev->dev.parent);
/* Set up IRQ handlers */
for (i = 0; i < ARRAY_SIZE(mbc_irq_handlers); i++)
pcf50633_register_irq(mbc->pcf, mbc_irq_handlers[i],
pcf50633_mbc_irq_handler, mbc);
psy_cfg.supplied_to = mbc->pcf->pdata->batteries;
psy_cfg.num_supplicants = mbc->pcf->pdata->num_batteries;
psy_cfg.drv_data = mbc;
/* Create power supplies */
mbc->adapter = power_supply_register(&pdev->dev,
&pcf50633_mbc_adapter_desc,
&psy_cfg);
if (IS_ERR(mbc->adapter)) {
dev_err(mbc->pcf->dev, "failed to register adapter\n");
return PTR_ERR(mbc->adapter);
}
usb_psy_cfg = psy_cfg;
usb_psy_cfg.attr_grp = pcf50633_mbc_sysfs_groups;
mbc->usb = power_supply_register(&pdev->dev, &pcf50633_mbc_usb_desc,
&usb_psy_cfg);
if (IS_ERR(mbc->usb)) {
dev_err(mbc->pcf->dev, "failed to register usb\n");
power_supply_unregister(mbc->adapter);
return PTR_ERR(mbc->usb);
}
mbc->ac = power_supply_register(&pdev->dev, &pcf50633_mbc_ac_desc,
&psy_cfg);
if (IS_ERR(mbc->ac)) {
dev_err(mbc->pcf->dev, "failed to register ac\n");
power_supply_unregister(mbc->adapter);
power_supply_unregister(mbc->usb);
return PTR_ERR(mbc->ac);
}
mbcs1 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS1);
if (mbcs1 & PCF50633_MBCS1_USBPRES)
pcf50633_mbc_irq_handler(PCF50633_IRQ_USBINS, mbc);
if (mbcs1 & PCF50633_MBCS1_ADAPTPRES)
pcf50633_mbc_irq_handler(PCF50633_IRQ_ADPINS, mbc);
return 0;
}
static int pcf50633_mbc_remove(struct platform_device *pdev)
{
struct pcf50633_mbc *mbc = platform_get_drvdata(pdev);
int i;
/* Remove IRQ handlers */
for (i = 0; i < ARRAY_SIZE(mbc_irq_handlers); i++)
pcf50633_free_irq(mbc->pcf, mbc_irq_handlers[i]);
power_supply_unregister(mbc->usb);
power_supply_unregister(mbc->adapter);
power_supply_unregister(mbc->ac);
return 0;
}
static struct platform_driver pcf50633_mbc_driver = {
.driver = {
.name = "pcf50633-mbc",
},
.probe = pcf50633_mbc_probe,
.remove = pcf50633_mbc_remove,
};
module_platform_driver(pcf50633_mbc_driver);
MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
MODULE_DESCRIPTION("PCF50633 mbc driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pcf50633-mbc");