qcom-spmi-temp-alarm.c
/*
* Copyright (c) 2011-2015, 2017, The Linux Foundation. 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.
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/iio/consumer.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/thermal.h>
#include "thermal_core.h"
#define QPNP_TM_REG_TYPE 0x04
#define QPNP_TM_REG_SUBTYPE 0x05
#define QPNP_TM_REG_STATUS 0x08
#define QPNP_TM_REG_SHUTDOWN_CTRL1 0x40
#define QPNP_TM_REG_ALARM_CTRL 0x46
#define QPNP_TM_TYPE 0x09
#define QPNP_TM_SUBTYPE_GEN1 0x08
#define QPNP_TM_SUBTYPE_GEN2 0x09
#define STATUS_GEN1_STAGE_MASK GENMASK(1, 0)
#define STATUS_GEN2_STATE_MASK GENMASK(6, 4)
#define STATUS_GEN2_STATE_SHIFT 4
#define SHUTDOWN_CTRL1_OVERRIDE_S2 BIT(6)
#define SHUTDOWN_CTRL1_THRESHOLD_MASK GENMASK(1, 0)
#define SHUTDOWN_CTRL1_RATE_25HZ BIT(3)
#define ALARM_CTRL_FORCE_ENABLE BIT(7)
/*
* Trip point values based on threshold control
* 0 = {105 C, 125 C, 145 C}
* 1 = {110 C, 130 C, 150 C}
* 2 = {115 C, 135 C, 155 C}
* 3 = {120 C, 140 C, 160 C}
*/
#define TEMP_STAGE_STEP 20000 /* Stage step: 20.000 C */
#define TEMP_STAGE_HYSTERESIS 2000
#define TEMP_THRESH_MIN 105000 /* Threshold Min: 105 C */
#define TEMP_THRESH_STEP 5000 /* Threshold step: 5 C */
#define THRESH_MIN 0
#define THRESH_MAX 3
/* Stage 2 Threshold Min: 125 C */
#define STAGE2_THRESHOLD_MIN 125000
/* Stage 2 Threshold Max: 140 C */
#define STAGE2_THRESHOLD_MAX 140000
/* Temperature in Milli Celsius reported during stage 0 if no ADC is present */
#define DEFAULT_TEMP 37000
struct qpnp_tm_chip {
struct regmap *map;
struct device *dev;
struct thermal_zone_device *tz_dev;
unsigned int subtype;
long temp;
unsigned int thresh;
unsigned int stage;
unsigned int prev_stage;
unsigned int base;
/* protects .thresh, .stage and chip registers */
struct mutex lock;
bool initialized;
struct iio_channel *adc;
};
/* This array maps from GEN2 alarm state to GEN1 alarm stage */
static const unsigned int alarm_state_map[8] = {0, 1, 1, 2, 2, 3, 3, 3};
static int qpnp_tm_read(struct qpnp_tm_chip *chip, u16 addr, u8 *data)
{
unsigned int val;
int ret;
ret = regmap_read(chip->map, chip->base + addr, &val);
if (ret < 0)
return ret;
*data = val;
return 0;
}
static int qpnp_tm_write(struct qpnp_tm_chip *chip, u16 addr, u8 data)
{
return regmap_write(chip->map, chip->base + addr, data);
}
/**
* qpnp_tm_get_temp_stage() - return over-temperature stage
* @chip: Pointer to the qpnp_tm chip
*
* Return: stage (GEN1) or state (GEN2) on success, or errno on failure.
*/
static int qpnp_tm_get_temp_stage(struct qpnp_tm_chip *chip)
{
int ret;
u8 reg = 0;
ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, ®);
if (ret < 0)
return ret;
if (chip->subtype == QPNP_TM_SUBTYPE_GEN1)
ret = reg & STATUS_GEN1_STAGE_MASK;
else
ret = (reg & STATUS_GEN2_STATE_MASK) >> STATUS_GEN2_STATE_SHIFT;
return ret;
}
/*
* This function updates the internal temp value based on the
* current thermal stage and threshold as well as the previous stage
*/
static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
{
unsigned int stage, stage_new, stage_old;
int ret;
WARN_ON(!mutex_is_locked(&chip->lock));
ret = qpnp_tm_get_temp_stage(chip);
if (ret < 0)
return ret;
stage = ret;
if (chip->subtype == QPNP_TM_SUBTYPE_GEN1) {
stage_new = stage;
stage_old = chip->stage;
} else {
stage_new = alarm_state_map[stage];
stage_old = alarm_state_map[chip->stage];
}
if (stage_new > stage_old) {
/* increasing stage, use lower bound */
chip->temp = (stage_new - 1) * TEMP_STAGE_STEP +
chip->thresh * TEMP_THRESH_STEP +
TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
} else if (stage_new < stage_old) {
/* decreasing stage, use upper bound */
chip->temp = stage_new * TEMP_STAGE_STEP +
chip->thresh * TEMP_THRESH_STEP -
TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
}
chip->stage = stage;
return 0;
}
static int qpnp_tm_get_temp(void *data, int *temp)
{
struct qpnp_tm_chip *chip = data;
int ret, mili_celsius;
if (!temp)
return -EINVAL;
if (!chip->initialized) {
*temp = DEFAULT_TEMP;
return 0;
}
if (!chip->adc) {
mutex_lock(&chip->lock);
ret = qpnp_tm_update_temp_no_adc(chip);
mutex_unlock(&chip->lock);
if (ret < 0)
return ret;
} else {
ret = iio_read_channel_processed(chip->adc, &mili_celsius);
if (ret < 0)
return ret;
chip->temp = mili_celsius;
}
*temp = chip->temp < 0 ? 0 : chip->temp;
return 0;
}
static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
int temp)
{
u8 reg;
bool disable_s2_shutdown = false;
WARN_ON(!mutex_is_locked(&chip->lock));
/*
* Default: S2 and S3 shutdown enabled, thresholds at
* 105C/125C/145C, monitoring at 25Hz
*/
reg = SHUTDOWN_CTRL1_RATE_25HZ;
if (temp == THERMAL_TEMP_INVALID ||
temp < STAGE2_THRESHOLD_MIN) {
chip->thresh = THRESH_MIN;
goto skip;
}
if (temp <= STAGE2_THRESHOLD_MAX) {
chip->thresh = THRESH_MAX -
((STAGE2_THRESHOLD_MAX - temp) /
TEMP_THRESH_STEP);
disable_s2_shutdown = true;
} else {
chip->thresh = THRESH_MAX;
if (chip->adc)
disable_s2_shutdown = true;
else
dev_warn(chip->dev,
"No ADC is configured and critical temperature is above the maximum stage 2 threshold of 140 C! Configuring stage 2 shutdown at 140 C.\n");
}
skip:
reg |= chip->thresh;
if (disable_s2_shutdown)
reg |= SHUTDOWN_CTRL1_OVERRIDE_S2;
return qpnp_tm_write(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, reg);
}
static int qpnp_tm_set_trip_temp(void *data, int trip, int temp)
{
struct qpnp_tm_chip *chip = data;
const struct thermal_trip *trip_points;
int ret;
trip_points = of_thermal_get_trip_points(chip->tz_dev);
if (!trip_points)
return -EINVAL;
if (trip_points[trip].type != THERMAL_TRIP_CRITICAL)
return 0;
mutex_lock(&chip->lock);
ret = qpnp_tm_update_critical_trip_temp(chip, temp);
mutex_unlock(&chip->lock);
return ret;
}
static const struct thermal_zone_of_device_ops qpnp_tm_sensor_ops = {
.get_temp = qpnp_tm_get_temp,
.set_trip_temp = qpnp_tm_set_trip_temp,
};
static irqreturn_t qpnp_tm_isr(int irq, void *data)
{
struct qpnp_tm_chip *chip = data;
thermal_zone_device_update(chip->tz_dev, THERMAL_EVENT_UNSPECIFIED);
return IRQ_HANDLED;
}
static int qpnp_tm_get_critical_trip_temp(struct qpnp_tm_chip *chip)
{
int ntrips;
const struct thermal_trip *trips;
int i;
ntrips = of_thermal_get_ntrips(chip->tz_dev);
if (ntrips <= 0)
return THERMAL_TEMP_INVALID;
trips = of_thermal_get_trip_points(chip->tz_dev);
if (!trips)
return THERMAL_TEMP_INVALID;
for (i = 0; i < ntrips; i++) {
if (of_thermal_is_trip_valid(chip->tz_dev, i) &&
trips[i].type == THERMAL_TRIP_CRITICAL)
return trips[i].temperature;
}
return THERMAL_TEMP_INVALID;
}
/*
* This function initializes the internal temp value based on only the
* current thermal stage and threshold. Setup threshold control and
* disable shutdown override.
*/
static int qpnp_tm_init(struct qpnp_tm_chip *chip)
{
unsigned int stage;
int ret;
u8 reg = 0;
int crit_temp;
mutex_lock(&chip->lock);
ret = qpnp_tm_read(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, ®);
if (ret < 0)
goto out;
chip->thresh = reg & SHUTDOWN_CTRL1_THRESHOLD_MASK;
chip->temp = DEFAULT_TEMP;
ret = qpnp_tm_get_temp_stage(chip);
if (ret < 0)
goto out;
chip->stage = ret;
stage = chip->subtype == QPNP_TM_SUBTYPE_GEN1
? chip->stage : alarm_state_map[chip->stage];
if (stage)
chip->temp = chip->thresh * TEMP_THRESH_STEP +
(stage - 1) * TEMP_STAGE_STEP +
TEMP_THRESH_MIN;
crit_temp = qpnp_tm_get_critical_trip_temp(chip);
ret = qpnp_tm_update_critical_trip_temp(chip, crit_temp);
if (ret < 0)
goto out;
/* Enable the thermal alarm PMIC module in always-on mode. */
reg = ALARM_CTRL_FORCE_ENABLE;
ret = qpnp_tm_write(chip, QPNP_TM_REG_ALARM_CTRL, reg);
chip->initialized = true;
out:
mutex_unlock(&chip->lock);
return ret;
}
static int qpnp_tm_probe(struct platform_device *pdev)
{
struct qpnp_tm_chip *chip;
struct device_node *node;
u8 type, subtype;
u32 res;
int ret, irq;
node = pdev->dev.of_node;
chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
dev_set_drvdata(&pdev->dev, chip);
chip->dev = &pdev->dev;
mutex_init(&chip->lock);
chip->map = dev_get_regmap(pdev->dev.parent, NULL);
if (!chip->map)
return -ENXIO;
ret = of_property_read_u32(node, "reg", &res);
if (ret < 0)
return ret;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
/* ADC based measurements are optional */
chip->adc = devm_iio_channel_get(&pdev->dev, "thermal");
if (IS_ERR(chip->adc)) {
ret = PTR_ERR(chip->adc);
chip->adc = NULL;
if (ret == -EPROBE_DEFER)
return ret;
}
chip->base = res;
ret = qpnp_tm_read(chip, QPNP_TM_REG_TYPE, &type);
if (ret < 0) {
dev_err(&pdev->dev, "could not read type\n");
return ret;
}
ret = qpnp_tm_read(chip, QPNP_TM_REG_SUBTYPE, &subtype);
if (ret < 0) {
dev_err(&pdev->dev, "could not read subtype\n");
return ret;
}
if (type != QPNP_TM_TYPE || (subtype != QPNP_TM_SUBTYPE_GEN1
&& subtype != QPNP_TM_SUBTYPE_GEN2)) {
dev_err(&pdev->dev, "invalid type 0x%02x or subtype 0x%02x\n",
type, subtype);
return -ENODEV;
}
chip->subtype = subtype;
/*
* Register the sensor before initializing the hardware to be able to
* read the trip points. get_temp() returns the default temperature
* before the hardware initialization is completed.
*/
chip->tz_dev = devm_thermal_zone_of_sensor_register(
&pdev->dev, 0, chip, &qpnp_tm_sensor_ops);
if (IS_ERR(chip->tz_dev)) {
dev_err(&pdev->dev, "failed to register sensor\n");
return PTR_ERR(chip->tz_dev);
}
ret = qpnp_tm_init(chip);
if (ret < 0) {
dev_err(&pdev->dev, "init failed\n");
return ret;
}
ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, qpnp_tm_isr,
IRQF_ONESHOT, node->name, chip);
if (ret < 0)
return ret;
thermal_zone_device_update(chip->tz_dev, THERMAL_EVENT_UNSPECIFIED);
return 0;
}
static const struct of_device_id qpnp_tm_match_table[] = {
{ .compatible = "qcom,spmi-temp-alarm" },
{ }
};
MODULE_DEVICE_TABLE(of, qpnp_tm_match_table);
static struct platform_driver qpnp_tm_driver = {
.driver = {
.name = "spmi-temp-alarm",
.of_match_table = qpnp_tm_match_table,
},
.probe = qpnp_tm_probe,
};
module_platform_driver(qpnp_tm_driver);
MODULE_ALIAS("platform:spmi-temp-alarm");
MODULE_DESCRIPTION("QPNP PMIC Temperature Alarm driver");
MODULE_LICENSE("GPL v2");