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pm8xxx-batt-alarm.c
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pm8xxx-batt-alarm.c
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/* Copyright (c) 2011, Code Aurora Forum. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* 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.
*/
/*
* Qualcomm PMIC PM8xxx Battery Alarm driver
*
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/mfd/pm8xxx/core.h>
#include <linux/mfd/pm8xxx/batt-alarm.h>
/* Available voltage threshold values */
#define THRESHOLD_MIN_MV 2500
#define THRESHOLD_MAX_MV 5675
#define THRESHOLD_STEP_MV 25
/* Register bit definitions */
/* Threshold register */
#define THRESHOLD_UPPER_MASK 0xF0
#define THRESHOLD_LOWER_MASK 0x0F
#define THRESHOLD_UPPER_SHIFT 4
#define THRESHOLD_LOWER_SHIFT 0
/* CTRL 1 register */
#define CTRL1_BATT_ALARM_ENABLE_MASK 0x80
#define CTRL1_BATT_ALARM_ENABLE 0x80
#define CTRL1_BATT_ALARM_DISABLE 0x00
#define CTRL1_HOLD_TIME_MASK 0x70
#define CTRL1_STATUS_UPPER_MASK 0x02
#define CTRL1_STATUS_LOWER_MASK 0x01
#define CTRL1_HOLD_TIME_SHIFT 4
#define CTRL1_HOLD_TIME_MIN 0
#define CTRL1_HOLD_TIME_MAX 7
/* CTRL 2 register */
#define CTRL2_COMP_UPPER_DISABLE_MASK 0x80
#define CTRL2_COMP_UPPER_ENABLE 0x00
#define CTRL2_COMP_UPPER_DISABLE 0x80
#define CTRL2_COMP_LOWER_DISABLE_MASK 0x40
#define CTRL2_COMP_LOWER_ENABLE 0x00
#define CTRL2_COMP_LOWER_DISABLE 0x40
#define CTRL2_FINE_STEP_UPPER_MASK 0x30
#define CTRL2_RANGE_EXT_UPPER_MASK 0x08
#define CTRL2_FINE_STEP_LOWER_MASK 0x06
#define CTRL2_RANGE_EXT_LOWER_MASK 0x01
#define CTRL2_FINE_STEP_UPPER_SHIFT 4
#define CTRL2_FINE_STEP_LOWER_SHIFT 1
/* PWM control register */
#define PWM_CTRL_ALARM_EN_MASK 0xC0
#define PWM_CTRL_ALARM_EN_NEVER 0x00
#define PWM_CTRL_ALARM_EN_TCXO 0x40
#define PWM_CTRL_ALARM_EN_PWM 0x80
#define PWM_CTRL_ALARM_EN_ALWAYS 0xC0
#define PWM_CTRL_PRE_MASK 0x38
#define PWM_CTRL_DIV_MASK 0x07
#define PWM_CTRL_PRE_SHIFT 3
#define PWM_CTRL_DIV_SHIFT 0
#define PWM_CTRL_PRE_MIN 0
#define PWM_CTRL_PRE_MAX 7
#define PWM_CTRL_DIV_MIN 1
#define PWM_CTRL_DIV_MAX 7
/* PWM control input range */
#define PWM_CTRL_PRE_INPUT_MIN 2
#define PWM_CTRL_PRE_INPUT_MAX 9
#define PWM_CTRL_DIV_INPUT_MIN 2
#define PWM_CTRL_DIV_INPUT_MAX 8
/* Available voltage threshold values */
#define THRESHOLD_BASIC_MIN_MV 2800
#define THRESHOLD_EXT_MIN_MV 4400
/*
* Default values used during initialization:
* Slowest PWM rate to ensure minimal status jittering when crossing thresholds.
* Largest hold time also helps reduce status value jittering. Comparators
* are disabled by default and must be turned on by calling
* pm8xxx_batt_alarm_state_set.
*/
#define DEFAULT_THRESHOLD_LOWER 3200
#define DEFAULT_THRESHOLD_UPPER 4300
#define DEFAULT_HOLD_TIME PM8XXX_BATT_ALARM_HOLD_TIME_16_MS
#define DEFAULT_USE_PWM 1
#define DEFAULT_PWM_SCALER 9
#define DEFAULT_PWM_DIVIDER 8
#define DEFAULT_LOWER_ENABLE 0
#define DEFAULT_UPPER_ENABLE 0
struct pm8xxx_batt_alarm_chip {
struct pm8xxx_batt_alarm_core_data cdata;
struct srcu_notifier_head irq_notifier_list;
struct work_struct irq_work;
struct device *dev;
struct mutex lock;
unsigned int irq;
int notifier_count;
u8 reg_threshold;
u8 reg_ctrl1;
u8 reg_ctrl2;
u8 reg_pwm_ctrl;
};
static struct pm8xxx_batt_alarm_chip *the_battalarm;
static int pm8xxx_reg_write(struct pm8xxx_batt_alarm_chip *chip, u16 addr,
u8 val, u8 mask, u8 *reg_save)
{
int rc = 0;
u8 reg;
reg = (*reg_save & ~mask) | (val & mask);
if (reg != *reg_save)
rc = pm8xxx_writeb(chip->dev->parent, addr, reg);
if (rc)
pr_err("pm8xxx_writeb failed; addr=%03X, rc=%d\n", addr, rc);
else
*reg_save = reg;
return rc;
}
/**
* pm8xxx_batt_alarm_enable - enable one of the battery voltage threshold
* comparators
* @comparator: selects which comparator to enable
*
* RETURNS: an appropriate -ERRNO error value on error, or zero for success.
*/
int pm8xxx_batt_alarm_enable(enum pm8xxx_batt_alarm_comparator comparator)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int rc;
u8 val_ctrl2 = 0, mask_ctrl2 = 0;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENODEV;
}
if (comparator < 0 || comparator > PM8XXX_BATT_ALARM_UPPER_COMPARATOR) {
pr_err("invalid comparator ID number: %d\n", comparator);
return -EINVAL;
}
if (comparator == PM8XXX_BATT_ALARM_LOWER_COMPARATOR) {
val_ctrl2 = CTRL2_COMP_LOWER_ENABLE;
mask_ctrl2 = CTRL2_COMP_LOWER_DISABLE_MASK;
} else {
val_ctrl2 = CTRL2_COMP_UPPER_ENABLE;
mask_ctrl2 = CTRL2_COMP_UPPER_DISABLE_MASK;
}
mutex_lock(&chip->lock);
/* Enable the battery alarm block. */
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_ctrl1,
CTRL1_BATT_ALARM_ENABLE,
CTRL1_BATT_ALARM_ENABLE_MASK, &chip->reg_ctrl1);
if (rc)
goto bail;
/* Enable the individual comparators. */
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_ctrl2, val_ctrl2,
mask_ctrl2, &chip->reg_ctrl2);
bail:
mutex_unlock(&chip->lock);
return rc;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_enable);
/**
* pm8xxx_batt_alarm_disable - disable one of the battery voltage threshold
* comparators
* @comparator: selects which comparator to disable
*
* RETURNS: an appropriate -ERRNO error value on error, or zero for success.
*/
int pm8xxx_batt_alarm_disable(enum pm8xxx_batt_alarm_comparator comparator)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int rc;
u8 val_ctrl1 = 0, val_ctrl2 = 0, mask_ctrl2 = 0;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENODEV;
}
if (comparator < 0 || comparator > PM8XXX_BATT_ALARM_UPPER_COMPARATOR) {
pr_err("invalid comparator ID number: %d\n", comparator);
return -EINVAL;
}
if (comparator == PM8XXX_BATT_ALARM_LOWER_COMPARATOR) {
val_ctrl2 = CTRL2_COMP_LOWER_DISABLE;
mask_ctrl2 = CTRL2_COMP_LOWER_DISABLE_MASK;
} else {
val_ctrl2 = CTRL2_COMP_UPPER_DISABLE;
mask_ctrl2 = CTRL2_COMP_UPPER_DISABLE_MASK;
}
mutex_lock(&chip->lock);
/* Disable the specified comparator. */
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_ctrl2, val_ctrl2,
mask_ctrl2, &chip->reg_ctrl2);
if (rc)
goto bail;
/* Disable the battery alarm block if both comparators are disabled. */
val_ctrl2 = chip->reg_ctrl2
& (CTRL2_COMP_LOWER_DISABLE_MASK | CTRL2_COMP_UPPER_DISABLE_MASK);
if (val_ctrl2 == (CTRL2_COMP_LOWER_DISABLE | CTRL2_COMP_UPPER_DISABLE))
val_ctrl1 = CTRL1_BATT_ALARM_DISABLE;
else
val_ctrl1 = CTRL1_BATT_ALARM_ENABLE;
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_ctrl1, val_ctrl1,
CTRL1_BATT_ALARM_ENABLE_MASK, &chip->reg_ctrl1);
bail:
mutex_unlock(&chip->lock);
return rc;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_disable);
/**
* pm8xxx_batt_alarm_threshold_set - set the lower and upper alarm thresholds
* @comparator: selects which comparator to set the threshold of
* @threshold_mV: battery voltage threshold in millivolts
* set points = 2500-5675 mV in 25 mV steps
*
* RETURNS: an appropriate -ERRNO error value on error, or zero for success.
*/
int pm8xxx_batt_alarm_threshold_set(
enum pm8xxx_batt_alarm_comparator comparator, int threshold_mV)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int step, fine_step, rc;
u8 val_threshold = 0, val_ctrl2 = 0;
int threshold_mask, threshold_shift, range_ext_mask, fine_step_mask;
int fine_step_shift;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENXIO;
}
if (comparator < 0 || comparator > PM8XXX_BATT_ALARM_UPPER_COMPARATOR) {
pr_err("invalid comparator ID number: %d\n", comparator);
return -EINVAL;
}
if (threshold_mV < THRESHOLD_MIN_MV
|| threshold_mV > THRESHOLD_MAX_MV) {
pr_err("threshold value, %d mV, is outside of allowable "
"range: [%d, %d] mV\n", threshold_mV,
THRESHOLD_MIN_MV, THRESHOLD_MAX_MV);
return -EINVAL;
}
if (comparator == PM8XXX_BATT_ALARM_LOWER_COMPARATOR) {
threshold_mask = THRESHOLD_LOWER_MASK;
threshold_shift = THRESHOLD_LOWER_SHIFT;
range_ext_mask = CTRL2_RANGE_EXT_LOWER_MASK;
fine_step_mask = CTRL2_FINE_STEP_LOWER_MASK;
fine_step_shift = CTRL2_FINE_STEP_LOWER_SHIFT;
} else {
threshold_mask = THRESHOLD_UPPER_MASK;
threshold_shift = THRESHOLD_UPPER_SHIFT;
range_ext_mask = CTRL2_RANGE_EXT_UPPER_MASK;
fine_step_mask = CTRL2_FINE_STEP_UPPER_MASK;
fine_step_shift = CTRL2_FINE_STEP_UPPER_SHIFT;
}
/* Determine register settings to achieve the threshold. */
if (threshold_mV < THRESHOLD_BASIC_MIN_MV) {
/* Extended low range */
val_ctrl2 |= range_ext_mask;
step = (threshold_mV - THRESHOLD_MIN_MV) / THRESHOLD_STEP_MV;
fine_step = step & 0x3;
/* Extended low range is for steps 0 to 2 */
step >>= 2;
} else if (threshold_mV >= THRESHOLD_EXT_MIN_MV) {
/* Extended high range */
val_ctrl2 |= range_ext_mask;
step = (threshold_mV - THRESHOLD_EXT_MIN_MV)
/ THRESHOLD_STEP_MV;
fine_step = step & 0x3;
/* Extended high range is for steps 3 to 15 */
step = (step >> 2) + 3;
} else {
/* Basic range */
step = (threshold_mV - THRESHOLD_BASIC_MIN_MV)
/ THRESHOLD_STEP_MV;
fine_step = step & 0x3;
step >>= 2;
}
val_threshold |= step << threshold_shift;
val_ctrl2 |= (fine_step << fine_step_shift) & fine_step_mask;
mutex_lock(&chip->lock);
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_threshold,
val_threshold, threshold_mask, &chip->reg_threshold);
if (rc)
goto bail;
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_ctrl2, val_ctrl2,
range_ext_mask | fine_step_mask, &chip->reg_ctrl2);
bail:
mutex_unlock(&chip->lock);
return rc;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_threshold_set);
/**
* pm8xxx_batt_alarm_status_read - get status of both threshold comparators
*
* RETURNS: < 0 = error
* 0 = battery voltage ok
* BIT(0) set = battery voltage below lower threshold
* BIT(1) set = battery voltage above upper threshold
*/
int pm8xxx_batt_alarm_status_read(void)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int status, rc;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENXIO;
}
mutex_lock(&chip->lock);
rc = pm8xxx_readb(chip->dev->parent, chip->cdata.reg_addr_ctrl1,
&chip->reg_ctrl1);
status = ((chip->reg_ctrl1 & CTRL1_STATUS_LOWER_MASK)
? PM8XXX_BATT_ALARM_STATUS_BELOW_LOWER : 0)
| ((chip->reg_ctrl1 & CTRL1_STATUS_UPPER_MASK)
? PM8XXX_BATT_ALARM_STATUS_ABOVE_UPPER : 0);
mutex_unlock(&chip->lock);
if (rc) {
pr_err("pm8xxx_readb failed, rc=%d\n", rc);
return rc;
}
return status;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_status_read);
/**
* pm8xxx_batt_alarm_hold_time_set - set hold time of interrupt output *
* @hold_time: amount of time that battery voltage must remain outside of the
* threshold range before the battery alarm interrupt triggers
*
* RETURNS: an appropriate -ERRNO error value on error, or zero for success.
*/
int pm8xxx_batt_alarm_hold_time_set(enum pm8xxx_batt_alarm_hold_time hold_time)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int rc;
u8 reg_ctrl1 = 0;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENXIO;
}
if (hold_time < CTRL1_HOLD_TIME_MIN
|| hold_time > CTRL1_HOLD_TIME_MAX) {
pr_err("hold time, %d, is outside of allowable range: "
"[%d, %d]\n", hold_time, CTRL1_HOLD_TIME_MIN,
CTRL1_HOLD_TIME_MAX);
return -EINVAL;
}
reg_ctrl1 = hold_time << CTRL1_HOLD_TIME_SHIFT;
mutex_lock(&chip->lock);
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_ctrl1, reg_ctrl1,
CTRL1_HOLD_TIME_MASK, &chip->reg_ctrl1);
mutex_unlock(&chip->lock);
return rc;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_hold_time_set);
/**
* pm8xxx_batt_alarm_pwm_rate_set - set battery alarm update rate *
* @use_pwm: 1 = use PWM update rate, 0 = comparators always active
* @clock_scaler: PWM clock scaler = 2 to 9
* @clock_divider: PWM clock divider = 2 to 8
*
* This function sets the rate at which the battery alarm module enables
* the threshold comparators. The rate is determined by the following equation:
*
* f_update = (1024 Hz) / (clock_divider * (2 ^ clock_scaler))
*
* Thus, the update rate can range from 0.25 Hz to 128 Hz.
*
* RETURNS: an appropriate -ERRNO error value on error, or zero for success.
*/
int pm8xxx_batt_alarm_pwm_rate_set(int use_pwm, int clock_scaler,
int clock_divider)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int rc;
u8 reg_pwm_ctrl = 0, mask = 0;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENXIO;
}
if (use_pwm && (clock_scaler < PWM_CTRL_PRE_INPUT_MIN
|| clock_scaler > PWM_CTRL_PRE_INPUT_MAX)) {
pr_err("PWM clock scaler, %d, is outside of allowable range: "
"[%d, %d]\n", clock_scaler, PWM_CTRL_PRE_INPUT_MIN,
PWM_CTRL_PRE_INPUT_MAX);
return -EINVAL;
}
if (use_pwm && (clock_divider < PWM_CTRL_DIV_INPUT_MIN
|| clock_divider > PWM_CTRL_DIV_INPUT_MAX)) {
pr_err("PWM clock divider, %d, is outside of allowable range: "
"[%d, %d]\n", clock_divider, PWM_CTRL_DIV_INPUT_MIN,
PWM_CTRL_DIV_INPUT_MAX);
return -EINVAL;
}
if (!use_pwm) {
/* Turn off PWM control and always enable. */
reg_pwm_ctrl = PWM_CTRL_ALARM_EN_ALWAYS;
mask = PWM_CTRL_ALARM_EN_MASK;
} else {
/* Use PWM control. */
reg_pwm_ctrl = PWM_CTRL_ALARM_EN_PWM;
mask = PWM_CTRL_ALARM_EN_MASK | PWM_CTRL_PRE_MASK
| PWM_CTRL_DIV_MASK;
clock_scaler -= PWM_CTRL_PRE_INPUT_MIN - PWM_CTRL_PRE_MIN;
clock_divider -= PWM_CTRL_DIV_INPUT_MIN - PWM_CTRL_DIV_MIN;
reg_pwm_ctrl |= (clock_scaler << PWM_CTRL_PRE_SHIFT)
& PWM_CTRL_PRE_MASK;
reg_pwm_ctrl |= (clock_divider << PWM_CTRL_DIV_SHIFT)
& PWM_CTRL_DIV_MASK;
}
mutex_lock(&chip->lock);
rc = pm8xxx_reg_write(chip, chip->cdata.reg_addr_pwm_ctrl, reg_pwm_ctrl,
mask, &chip->reg_pwm_ctrl);
mutex_unlock(&chip->lock);
return rc;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_pwm_rate_set);
/*
* Handle the BATT_ALARM interrupt:
* Battery voltage is above or below threshold range.
*/
static irqreturn_t pm8xxx_batt_alarm_isr(int irq, void *data)
{
struct pm8xxx_batt_alarm_chip *chip = data;
disable_irq_nosync(chip->irq);
schedule_work(&chip->irq_work);
return IRQ_HANDLED;
}
static void pm8xxx_batt_alarm_isr_work(struct work_struct *work)
{
struct pm8xxx_batt_alarm_chip *chip
= container_of(work, struct pm8xxx_batt_alarm_chip, irq_work);
int status;
if (!chip)
return;
status = pm8xxx_batt_alarm_status_read();
if (status < 0)
pr_err("failed to read status, rc=%d\n", status);
else
srcu_notifier_call_chain(&chip->irq_notifier_list,
status, NULL);
enable_irq(chip->irq);
}
/**
* pm8xxx_batt_alarm_register_notifier - register a notifier to run when a
* battery voltage change interrupt fires
* @nb: notifier block containing callback function to register
*
* nb->notifier_call must point to a function of this form -
* int (*notifier_call)(struct notifier_block *nb, unsigned long status,
* void *unused);
* "status" will receive the battery alarm status; "unused" will be NULL.
*
* RETURNS: an appropriate -ERRNO error value on error, or zero for success.
*/
int pm8xxx_batt_alarm_register_notifier(struct notifier_block *nb)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int rc;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENXIO;
}
rc = srcu_notifier_chain_register(&chip->irq_notifier_list, nb);
mutex_lock(&chip->lock);
if (rc == 0) {
if (chip->notifier_count == 0) {
enable_irq(chip->irq);
rc = irq_set_irq_wake(chip->irq, 1);
}
chip->notifier_count++;
}
mutex_unlock(&chip->lock);
return rc;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_register_notifier);
/**
* pm8xxx_batt_alarm_unregister_notifier - unregister a notifier that is run
* when a battery voltage change interrupt fires
* @nb: notifier block containing callback function to unregister
*
* RETURNS: an appropriate -ERRNO error value on error, or zero for success.
*/
int pm8xxx_batt_alarm_unregister_notifier(struct notifier_block *nb)
{
struct pm8xxx_batt_alarm_chip *chip = the_battalarm;
int rc;
if (!chip) {
pr_err("no battery alarm device found.\n");
return -ENXIO;
}
rc = srcu_notifier_chain_unregister(&chip->irq_notifier_list, nb);
if (rc == 0) {
mutex_lock(&chip->lock);
chip->notifier_count--;
if (chip->notifier_count == 0) {
rc = irq_set_irq_wake(chip->irq, 0);
disable_irq(chip->irq);
}
WARN_ON(chip->notifier_count < 0);
mutex_unlock(&chip->lock);
}
return rc;
}
EXPORT_SYMBOL(pm8xxx_batt_alarm_unregister_notifier);
static int pm8xxx_batt_alarm_reg_init(struct pm8xxx_batt_alarm_chip *chip)
{
int rc = 0;
/* save the current register states */
rc = pm8xxx_readb(chip->dev->parent, chip->cdata.reg_addr_threshold,
&chip->reg_threshold);
if (rc)
goto bail;
rc = pm8xxx_readb(chip->dev->parent, chip->cdata.reg_addr_ctrl1,
&chip->reg_ctrl1);
if (rc)
goto bail;
rc = pm8xxx_readb(chip->dev->parent, chip->cdata.reg_addr_ctrl2,
&chip->reg_ctrl2);
if (rc)
goto bail;
rc = pm8xxx_readb(chip->dev->parent, chip->cdata.reg_addr_pwm_ctrl,
&chip->reg_pwm_ctrl);
if (rc)
goto bail;
bail:
if (rc)
pr_err("pm8xxx_readb failed; initial register states "
"unknown, rc=%d\n", rc);
return rc;
}
/* TODO: should this default setting function be removed? */
static int pm8xxx_batt_alarm_config_defaults(void)
{
int rc = 0;
/* Use default values when no platform data is provided. */
rc = pm8xxx_batt_alarm_threshold_set(PM8XXX_BATT_ALARM_LOWER_COMPARATOR,
DEFAULT_THRESHOLD_LOWER);
if (rc) {
pr_err("threshold_set failed, rc=%d\n", rc);
goto done;
}
rc = pm8xxx_batt_alarm_threshold_set(PM8XXX_BATT_ALARM_UPPER_COMPARATOR,
DEFAULT_THRESHOLD_UPPER);
if (rc) {
pr_err("threshold_set failed, rc=%d\n", rc);
goto done;
}
rc = pm8xxx_batt_alarm_hold_time_set(DEFAULT_HOLD_TIME);
if (rc) {
pr_err("hold_time_set failed, rc=%d\n", rc);
goto done;
}
rc = pm8xxx_batt_alarm_pwm_rate_set(DEFAULT_USE_PWM,
DEFAULT_PWM_SCALER, DEFAULT_PWM_DIVIDER);
if (rc) {
pr_err("pwm_rate_set failed, rc=%d\n", rc);
goto done;
}
rc = pm8xxx_batt_alarm_disable(PM8XXX_BATT_ALARM_LOWER_COMPARATOR);
if (rc) {
pr_err("disable lower failed, rc=%d\n", rc);
goto done;
}
rc = pm8xxx_batt_alarm_disable(PM8XXX_BATT_ALARM_UPPER_COMPARATOR);
if (rc) {
pr_err("disable upper failed, rc=%d\n", rc);
goto done;
}
done:
return rc;
}
static int __devinit pm8xxx_batt_alarm_probe(struct platform_device *pdev)
{
const struct pm8xxx_batt_alarm_core_data *cdata
= pdev->dev.platform_data;
struct pm8xxx_batt_alarm_chip *chip;
struct resource *res;
int rc;
if (the_battalarm) {
pr_err("A PMIC battery alarm device has already probed.\n");
return -ENODEV;
}
if (!cdata) {
pr_err("missing core data\n");
return -EINVAL;
}
if (!cdata->irq_name) {
pr_err("missing IRQ name\n");
return -EINVAL;
}
chip = kzalloc(sizeof(struct pm8xxx_batt_alarm_chip), GFP_KERNEL);
if (chip == NULL) {
pr_err("kzalloc() failed.\n");
return -ENOMEM;
}
res = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
cdata->irq_name);
if (res) {
chip->irq = res->start;
} else {
pr_err("Battery alarm IRQ not specified\n");
rc = -EINVAL;
goto err_free_chip;
}
chip->dev = &pdev->dev;
memcpy(&(chip->cdata), cdata,
sizeof(struct pm8xxx_batt_alarm_core_data));
srcu_init_notifier_head(&chip->irq_notifier_list);
chip->notifier_count = 0;
mutex_init(&chip->lock);
the_battalarm = chip;
rc = pm8xxx_batt_alarm_reg_init(chip);
if (rc)
goto err_free_mutex;
rc = pm8xxx_batt_alarm_config_defaults();
if (rc)
goto err_free_mutex;
INIT_WORK(&chip->irq_work, pm8xxx_batt_alarm_isr_work);
/* TODO: Is it best to trigger on both edges? Should this be configurable? */
rc = request_irq(chip->irq, pm8xxx_batt_alarm_isr,
IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, cdata->irq_name,
chip);
if (rc < 0) {
pr_err("request_irq(%d) failed, rc=%d\n", chip->irq, rc);
goto err_cancel_work;
}
/* Disable the IRQ until a notifier is registered. */
disable_irq(chip->irq);
platform_set_drvdata(pdev, chip);
return 0;
err_cancel_work:
cancel_work_sync(&chip->irq_work);
err_free_mutex:
mutex_destroy(&chip->lock);
srcu_cleanup_notifier_head(&chip->irq_notifier_list);
err_free_chip:
kfree(chip);
the_battalarm = NULL;
return rc;
}
static int __devexit pm8xxx_batt_alarm_remove(struct platform_device *pdev)
{
struct pm8xxx_batt_alarm_chip *chip = platform_get_drvdata(pdev);
if (chip) {
platform_set_drvdata(pdev, NULL);
irq_set_irq_wake(chip->irq, 0);
free_irq(chip->irq, chip);
cancel_work_sync(&chip->irq_work);
srcu_cleanup_notifier_head(&chip->irq_notifier_list);
mutex_destroy(&chip->lock);
kfree(chip);
the_battalarm = NULL;
}
return 0;
}
static struct platform_driver pm8xxx_batt_alarm_driver = {
.probe = pm8xxx_batt_alarm_probe,
.remove = __devexit_p(pm8xxx_batt_alarm_remove),
.driver = {
.name = PM8XXX_BATT_ALARM_DEV_NAME,
.owner = THIS_MODULE,
},
};
static int __init pm8xxx_batt_alarm_init(void)
{
return platform_driver_register(&pm8xxx_batt_alarm_driver);
}
static void __exit pm8xxx_batt_alarm_exit(void)
{
platform_driver_unregister(&pm8xxx_batt_alarm_driver);
}
module_init(pm8xxx_batt_alarm_init);
module_exit(pm8xxx_batt_alarm_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("PMIC PM8xxx Battery Alarm");
MODULE_VERSION("1.0");
MODULE_ALIAS("platform:" PM8XXX_BATT_ALARM_DEV_NAME);